Proceedings of the KIEE Conference (대한전기학회:학술대회논문집)
The Korean Institute of Electrical Engineers (대한전기학회)
 기타
1996.07

In order to improve the voltage profile of the system we introduce the reactive power devices. However, it is difficult to know which bus will be the most effective bus when we inject the reactive power supplier in it. This paper systematically determines indices of the system in order to locate reactive power devices in a power system. To prove the validity and effectiveness of the system we apply the proposed method to the 9 bus system.

This paper presents the study results of four transmission methods to enchance transmission capability. The four transmission methods studied were FACTS, HVDC, High Phase Order and new conductor material method. The study was Performed based on mid and long term KEPCO system in 2000 and 2006 year. Among them FACTS(Flexible AC Transmission System) is an exciting new field which holds great promise for improved utilization of AC transmission systems.

A study of the coordinated control of a TCSC and an existing PSS is presented when both are used to damp the low frequency oscillations. TCSC is modeled by the first order delay model. Linear quadratic Gaussian controller is used for designing PSS and TCSC supplementary controller. The performance of the proposed controllers is simulated in a one machine infinite bus model. As a result, it is shown that to damp the low frequency oscillations efficiently, it is necessary to control TCSC and PSS simultaneously.

The objective of this paper is to compare the series and shunt approaches of controlled reactive power compensation to improve power system transient stabilities. Including main circuit considerations of series and shunt compensators, application aspects are thought to have major impacts on efficiency and economy of the installation of the compensators. The concept is studied by means of EMTP simulations on one machineInfinite Bus Test System which consists of a 612MVA steam turbin generator and transformer and double circuit 345KV transmission line. Idealized dynamic models of Thyristor Controlled Series Compensation and Shunt Compensation are used for the comparative study of the series and shunt compensation approach to damp power system oscillations.

This paper prescribe the effects of SVC & TCSC in multimachine power system. EMTP models of two FACTS controllers are proposed to analysis the basic characteristics of SVC & TCSC and the control signal of TCR is determined by rms value which was measured in system. The oscillation model of generator is proposed to analysis the damping effect and the most effective location of TCSC in multimachine power system is identified by the residues associated with the natural oscillation modes. The 3 generator9 bus model system is used to demonstrate the applicability of the proposed model.

The thyristor controlled series compensator can vary the impedance continuously to levels below and up to the line's natural impedance, thus enabling transmission line capability to be increased and power flow to be controlled. The dynamic performance of TCSC to increase the power system damping is mainly analyzed in this paper. The TCSC controller used here is of the PID type and the input signal to the controller is the active power flow through the TCSC. The TCSC parameters are determined so as to minimize the modal performance measure for duping of power system oscillations.

The role of protective relaying system is important in the power system stability and reliability. Conventional relaying schemes have had many problems that adaptiveness for delicate variance of objective power systems is poor, and so on. In these days, in order to overcome the weaknesses, the studies to application of artificial intelligent scheme are required. In this paper, as the preceding research for development of intelligent protective relays, we tried to select the most suitable digital filter using comparison of frequency response and performance of wanted frequency component extraction etc.

The conventional relay which determines the fault state based on the current and voltage has a certain limitations due to the uncertainties involved in the data and the decision making criteria. This study proposes the fuzzy relay applying the BeliefMeasure to make a decision on the fault based on the various criteria and integrated data.

Simulation methods using EMTP to analyze power transformer transient characteristics and their interesting results are presented in this paper. Because of the transformer saturation including initial inrush, the conventional current differential relay with harmonic restraint module does not provide a clear distinction between internal faults and other conditions. Providing the bases to develop a new relaying concept for power transformer protection, transformer nonlinear transient characteristics are analyzed.

In this paper, we suggested the verification method of protective algorithms using EMTDC(ElectroMagnetic Transient DC). In other to verify protective algorithms using EMTDC, we first had to make a user defined component and then applied it to a simple power system with parallel line. By means of this method, We reduced the much time and effort to develop or improve the protective algorithm of digital protective relay. For the future, we apply this method to IDPACS(Integrated Digital Protection and Control System) and intend to implement more reliable digital protective relays.

This paper describes a method to improve the speed of a distance relay based on a differential equation of transmission lines using feedforward artificial neural networks (ANN) on an EHV system. For the impedance calculation an integration approximation to the differential equation is used and then an ANN is trained with the impedance convergence characteristic. The ANN predicts the fault distance with some calculated resistances and reactances before they reach trip zone. Thus, the proposed method can improve the speed of distance relays, significantly if a high sampling rate such as 48 samples per cycle is employed.

Korea Distribution Automation System(KODAS) has been designed and implemented for feeder automation using the paircable as communication media. And we bave been developed the telemetering system using the low voltage line. Kepco have been constructed approximately 60% of the Cable TV(CATV) networks in large city in Korea since 1995, so we have been researching the feeder automation based on CATV networks also. We will contruct the system using its in the area with of cableTV networks and paircable line in the other area for communication media in future.

A computer program for calculation of induced lightning overvoltages on the multiconductor overhead distribution lines has been developed. This program is very useful in a wide range of applications for investigating the effects on distribution lines of lightning protection equipment such as lightning arresters, overhead ground wire and arcing devices.

Network reconfiguration is performed by opening/closing two types of switches, tie and sectionalizing switches. A whole feeder, or part of a feeder, may be served from another feeder by closing a tie switch linking the two while an appropriate sectionalizing switch must be opened to maintain radial structures. In loss reduction, the problem is to identify tie and sectionalizing switches that should be closed and opened, respectively, to achieve a maximum loss reduction. In this paper, it is introduced to propose the reconfiguration plan for loss reduction by using the Civanlar's loss reduction formular.

Our country, is still suffering from much work outage, nearly 80% of total outage time, in 22.9kVY multigrounded distribution lines. Therefore, KEPCO which is the sole utility owned by the Korean government ms developed outagefree work techniques to improve the reliability of power supply in Our country. This paper is to introduce the developing process and good effects of outagefree work techniques, and the equipment developed and applied in Our country. This paper will aid many utilities to try to reduce the work outage.

Recently, rapid increase in electricity demand, tremendous financial need for new power plant construction, and environmental problem have led to search for more efficient energy production and energy conservation technologies. Due to the potential energy and cost savings to electric utilities, DSM plays an important role in the electric resource planning. However, implementation of costeffective DSM program requires appropriate analysis methodologies and procedures. In this study, we present the costeffectiveness analysis model for DSM program evaluation. We also present a case study to analyze DSM program.

Main theme of this paper is to evaluate the degree of risk due to the uncertainly of the future, especially for the longterm integrated resource planning (IRP) in electric utility. The measures of uncertainty for dealing with planning risk in the IRP context include robustness and flexibility of each candidate resource plan. The uncertainty indices are treated as decision criteria, or attributes, same as economic efficiency or reliability criteria in the multiattribute decisionmaking (MCDM) procedure of IRP.

A knowledge based forecasting system for special days has been developed for the economic and secure operation of electric power system. Ifthen production rules has been adopted in this system to be used in various environmental conditions. Graphic user interfaces enables a user to access easily to the system. The simulation based on the historical data have shown that the forecasting result was improved remarkably when compared to the results from the conventional statistical methods. The forecasting results can be used for power system operational planning to improve security and economy of the power system.

Maintenance scheduling plays an important role in evaluating the supply reliability of power systems. Since generating units must be maintained and inspected, the generation planner must schedule planned outages during the year. Several factors entering into this scheduling analysis include: seasonal loaddemand profile, amount of maintenance to bo done on all generating units, size of the units, elapsed time from last maintenance, and availability of maintenance crews. This paper proposes a new algorithm to decide the multiyear maintenance scheduling with considering the total cost. We adjust the maintenance scheduling to levelize the reliability over all period. The proposed algorithm is applied to a real size power system and the developed reliability results are obtained.

This paper presents a new algorithm of unit commitment for optimal operation in power system. The proposed method developed algorithm that determined generators considering load variations at each stages. It has established forecast unit commitment over time horizon at first and next calculated quality cost of generators and then committed generator that has minimum quality cost at unit commitment schedule over time horizon. It is used that ObjetOriented Programming for effective realization, and simple handling of complex program. The proposed method has applied at example system and the results has shown superior economics and computational requirement than the conventional method.

This paper is to build and develop the generation schedule program to provide a stable power supply and economic operation of power generation system. A practical algorithm is presented for solving the thermal unit commitment problem which is one of very important areas in economic operation of power system. This algorithm is based on priority ordering by the unit generation cost and it is shown that the operation cost of chosen sets of generators is the minimum. The proposed method is proven to be very practical, accurate and efficient in a KEPCO system.

This paper proposes a unit commitment scheduling method based on Genetic Algorithm(GA). Due to a variety of constraints to be satisfied, the search space of the UC problem is highly nonconvex, so the UC problem cannot be solved efficiently only using the standard GA To efficiently deal with the constraints of the problem and greatly reduce the search space of the GA, the minimum up and down time constraints are embedded in the binary strings that are coded to represent the onoff states of the generating units. The violations of other constraints arc handled by integrating penalty factors. To show the effectiveness of the GA based unit commitment scheduling, test results for system of 5 units are compared with results obtained using Lagrangian Relaxation and Dynamic Programming.

This paper presents an optimization method for optimal reactive power dispatch which minimizes real power loss and improves voltage profile of power systems using evolutionary computation such as genetic algorithms(GAs), evolutionary programming(EP). and evolution strategy(ES). Many conventional methods to this problem have been proposed in the past, but most these approaches have the common defect of being caught to a local minimum solution. Recently, global search methods such as GAs, EP, and ES are introduced. The proposed methods were applied to the IEEE 30bus system. Each simulation result, compared with that obtained by using a conventional gradientbased optimization method, Sequential Quadratic Programming (SQP), shows the possibility of applications of evolutionary computation to large scale power systems.

An artificial neural network(ANN) modeling is presented using the Inputoutput power characteristics of SMES. When using the ANN which functions as a modelfree system, network construction and determination of learning parameters are carefully chosen to represent the complicated nonlinear inputoutput relation from the blackboxed SMES system. The proposed ANNbased SMES model is applied to analyse the power system stability and the simulation results provide the property of this approach.

The recent summer power peak crisis has been caused by excessive use of cooling loads at daily peak time in summer. The yearly load shape of KEPCO has gradually became very steep valley. Under this situation, more efficient DSM(Demand Side Management) tools are fully required for summer peak clipping and shaving. In this paper, the KEPCO's JejuDo model project for DSM, especially for Demand Controller, is presented. Demand Controller was evaluated to have the very high economical efficiency against the investment in equipment, as compared with another DSM tools. There were some serious problem to apply Demand Controller to many customers in the aspect to synchronization with KEPCO's watthour meter. But these problems have solved by Keyin's new Demand Controller using vision algorithm.

In this paper, we propose an optimal daily operation model for the total energy system which includes cogeneration, thermal storage and electrical charger and ice storage facilities. Storing and utilizing the surplus thermal and electrical energy, the daily operation cost could be reduced and more efficient use of thermal energy could be achieved. The ice storage cooling system has a merit of reduce the electricity cost by time of day rate(peak/offpeak). And also, refrigerator can be down sized compare to the other cooling system From this model, operation costs of the sample cogeneration system with/without auxiliary facilities are obtained and compared to each other. In case study, the sensitivity of operating cost is simulated according to the variation of cogeneration production cost, electricity rate, etc.

This paper presents a new online generator simulator which can be utilized for the control parameter setting of the exciter and the power system stabilizer (PSS). The proposed simulator equipped with A/D and D/A channels through which actual exciter and PSS can be connected. System parameters and disturbance sequence are easily programmed using friendly developed interface. The developed simulator is tested and verified by connecting a simple AVR implemented by opamps.

In this paper, a new timedomain reduction method for unbalanced 3 phase power systems will be represented. The impulse response of the system is used to identify a discretetime equivalent filter model. The model is formulated directly in the phase domain. Each phase has a selfmode equivalent model and two mutualmode equivalent models. The equivalent model is determined by the transfer function identification technique based on the Prony analysis. The model is implemented in EMTDC and tested with an unbalanced 3 phase network. The result of test showed that the equivalent model is accurate.

This paper presents a method of calculating a selective number of eigenvalues in power systems, which are rightmost, or are largest modulus. The modified Arnoldi method in conjunction with implicit shift ORalgorithm is used to calculate the rightmost eigenvalues. Algorithm requires neither a prior knowledge of the specified shifts nor the calculation of inverse matrix. The key advantage of the algorithm is its ability to converge to the wanted eigenvalues at once. The method is compared with the modified Arnoldi method combined with Smatrix transformation, where the eigenvalues having the largest modulus are to be determined. The two methods are applied to the reduced Kansai system. Convergence characteristics and performances are compared. Results show that both methods are robust and has good convergence properties. However, the implicit shift OR method is seen to be faster than the Smatrix method under the same condition.

Abnormal conditions and disturbances in distribution system cause an immediate influence to the customers. Conventional detection schemes for the distribution abnormalities have been applied in limited extents mainly because of their low reliability. In this paper, we developed a disturbance identification system which monitors the load level after a transient, checks the harmonic behavior of the load, and finally makes decision on the cause of the disturbance. This system identifies and discriminates overcurrent faults, arcing ground faults, recloser activities, and foreign object or tree contacts. In the implementation of the identification system, we applied fuzzy logic to better represent some variables whose Quantities are expressed only in nonnumerical terms.

This paper analyzes the Impact of customer system at the transients due to autoreclosing on 22.9kV distribution lines. The various factors affecting this phenomena are analyzed In detail through parametric studies. These factors Include the fault current, fault location, reclosing angle, capacitor bank size, and customer load characteristics. The impacts of these transients on customer system are described and available to identify the optimal autoreclosing scheme.

This paper presents an approach for the analysis of static voltage stability in power system. The proposed approach is based on multiple load flow calculation method using the redistribution algorithm of transmission loss, with which more realistic load flow solution can be obtained in the near of voltage collapse point. Some simulation results of the proposed approach show that the accuracy of static voltage stability analysis can be increased.

House load operation (HLO) is the Willy of a plant to continue to operate while completely separated from the transmission system. HLO capability is recently adopted as basic design requirement for nuclear power plants, since HLO capability increases the plant availability and power system reliability. However, HLO results in the voltage and frequency transients to motors and pumps. This paper presents the computer simulation results such as the transient speeds, voltages, and control system responses of turbine/g enerator during HLO. This paper also suggests the plant design features required for HLO capability and the transient speed/vlitage limits caused by HLO.

This paper presents a new method for first and second order eigensensitivity analysis of system matrix in augmented form. Eigensensitivity analysis provides invaluable informations in power system planning and operation. However, conventional eigensensitivity analysis methods, which need all the eigenvalues and eigenvectors, can not be applicable to large scale power systems due to large computer memory and computing time required. In the proposed method, all sensitivity computations for a mode are carried out using the augmented system matrix and its own eigenvalue and right & left eigenvectors. In other words sensitivity analysis for a mode does not need informations on the other eigenvalues and eigenvectors and sparsity technique can be fully utilized. Thus compuations can be done very efficiently with moderate computer memory and computing time even for large power systems. The proposed algorithm is tested for one machine infinite bus system.

In this paper, polymer housing arrester has very good characteristics in design versatility as well as excellent resistance to moist ingress and pollution performance. For the presented of the characteristics evaluation and technology of disk spring and knuckle structure of FRP to filament winding seems to protect the arrester elements from moisture absorption. The achievement in the research and technology will contribute to the showed very good characteristic in adhesion of terminal cap and FRP cylinder for outdoor arresters and domestic products of high voltage power distribution arrester.

This paper proposes an application of artificial neural networks to the busbar separation in a substation for radial network operation. For the effective busbar operation, the insecurity index of transmission line load is introduced. For the radial network operation. the constraints of busbar switch is formulated in the performance function with the insecurity index. The determination of busbar switching is to find the states of 0 or 1 in the circuit breakers. In this paper, it is tested that the busbar separation of binary optimization problem can be solved by Hopfield networks with adequate manipulations.

This paper presents an algorithm for the contingency ranking in a power system. The method utilizes line outage distribution factors(LODF) which are established from DC load flow solutions. The LODF are formulated using changes in network power generations to simulate the outaged line from the network. To abtain better ranking. one can take a line loading of 60% over into account in the computation of PI. The proposed algorithm has been validated in tests on a 6bus test system.

The Operating Method of Superconducting Fault Current Limiter for Total Superconducting Power SystemDesign & operation of power system for meeting increase of electric power demands is becoming more difficult and complex. One of reasons is increase of fault current. As one of the most effective methods for suppressing the fault currents, installation of SFCL are expected. An image of future hybrid & total SC power system which have introduced SC generator cable transformer, fault current limiter, SMES & shunt reactor, etc. are presented. In the SC power system, it is pointed that a SFCL should play an, important part of quenching current level coordination to prevent the other SC devices from quench.

This paper propose neural network which is one of selforganizing techniques. It is composed neural network controller as input signal is error and change of error which is optimal output, and is learned system by using a error backpropagation learning algorithm is one of error mimizing learning methods. In order to achieve practical real time control reduce on learning time, it is applied to loadfrequency control of nonlinear power system with using a moment learning method. It is described in such a case considering constraints for a rate of increace generationrate.

This paper reports the protection coordination program, INPROSET for the industrial power system to determine the optimal TAP and TimeDial of OCRs. INPROSET performs two stages process and the first stage starts form the highest level and depending on its results, the second stage achieves the higher relay operating time. The developed system proved effective through the tests on the real systems.

This paper presents a new development of realtime generator simulator which is operating on PC environment. User friendly made interfaces make it possible for any users to utilize the simulator immediately with very little learning efforts. Also, the realtime simulation gives much more practical operation feeling to the users. It provides a very useful tool for analyzing system dynamics and developing the power system control schemes.

The predictive maximum demand controllers often bring about large number of control actions during the every integrating period and/or undesirable loaddisconnecting operations during the begining stage if the integrating period. To solve these problems, a fuzzy predictive maximum demand control algorithm is proposed, which determines the sensitivity if control action by urgency if the load interrupting action along with the predicted demand reading to the target or the time arriving at the end stage if the integrating period. A prototype controller employing the proposed algorithm also is developed and its performances are tested by PROCOM SYSTEMS Corperation of Korea.

An important purpose of screening DSM(Demand Side Management) programs is to determine which programs or technologies seem to be moot worthy of further development, given the characteristics of the particular utility system. Complication found in screening DSM technologies is the consideration of costs and benefits from several perspectives : the utility, society, participants, free riders and nonparticipants. In this paper, a nationwide DSM screening model is presented using a rigorous mathematical formulation on the financial basis and the concept of marginal coots considering all affected parties inside the nation is fully exploited.

This paper presents some stability simulations using EMTP to see the effect of EHV Lines with hybrid reclosing on power system stability. The Hybrid reclosing on EHV lines can improve the reliability of power systems. These studies is performed as a part of the research work which is aimed to find proper scheme of reclosing for EHV lines in Korea. Completing a number of simulation works with the diverse conditions such as ones reported in this paper, some decisions could be made through some stochastic approches for the simulation results for the proper scheme of reclosing for Korean systems.

This paper describes a Transient Stability Education & Training Software that can make the students or beginners easily be familiar with power system stability problems. The Major objective of this study is to provide, for educational purpose, an interactive computer graphic tool that can facilitate power system study in highly userfriendly environment. The proposed software is designed to have the particular features such as follow : simulation with animation of the rotor, useful interactive scheme, various graphic illustrations related to critical factors of the stability, trace function including revival simulation with different processing speed. With these features, the software could be suitable for educational and training of students/beginners in power system stability engineering field.

According to increase in electric power demand, the increasing rate of peak load compared with that of base load grows larger every year. Thus this paper deals with the optimal dynamic dispatch problem due to power rate limits and spinning reserve with loss or without loss. The first is adjusting module for gradual change of generator power by ObjectOriented Programming. The latter is an efficient dispatch module for the consideration of reasonable spinning reserve requirements. The proposed algorithm has been shown efficiency in real power system with loss.

This study proposes a new algorithm which performs a production simulation under various constraints and maintains computational efficiency. In order to consider the environmental and operational constraints, the proposed algorithm is based on optimization techniques formulated in LP form In the algorithm, "system characteristic constraints" reflect the system characteristics such as LDC shape, unit loading order and forced outage rate. By using the concept of Energy Invariance Property and two operational rules i.e. Compliance Rule for Emission Constraint, Compliance Rule for Limited Energy of Individual Unit, the number of system characteristic constraints is appreciably reduced. As a solution method of the optimization problem, the author uses Karmarkar's method which performs effectively in solving large scale LP problem. The efficiency of production simulation is meaningful when it is effectively used in power system planning. With the proposed production simulation algorithm, an optimal expansion planning model which can cope with operational constraints, environmental restriction, and various uncertainties is developed. This expansion planning model is applied to the long range planning schemes by WASP, and determines an optimal expansion scheme which considers the effect of supply interruption, load forecasting errors, multistates of unit operation, plural limited energy plants etc.

This paper presents a simple method for evaluating of voltage stability using the line flow equation. Line flow equations(
$P_{ij}$ ,$Q_{ij}$ ) are comprised of state variable,$V_i$ ,${\delta}_i$ ,$V_j$ and${\delta}_j$ , and line parameter, r and x. Using the feature of polar coordinate, these equations become one equation with two variables,$V_i$ and$V_j$ . Moreover, if bus j is slack bus or generator bus, which is specified voltage magnitude, it becomes One equation with one variable$V_i$ , that is, may be formulated with the secondorder equation for$V_i^2$ . Therefore, solutions are obtained with simple computation. Solutions obtained are used for evaluating of voltage stability through sensitivity analysis. Also, considering of reactive power source, method for evaluating the voltage stability is introduced. The proposed method was validated to 2bus and IEEE 6bus system. 
This paper proposes the algorithm to solve emergency service restoration problems using efficient reconfiguration method in distribution system. In this algorithm, we try to avoid the blackout of important loads by considering service rank. It is possible to reconfigurate the system by using fuzzy inference results in which was reflected the expected distribution power, line capacity and service rank. A 27bus, 32branch model system is used to demonstrate the effectiveness of the proposed algorithm.

This paper addresses the smallsignal stability and control problems associated with a Static Var Compensator and its power system stabilizer. The major emphasis is on determination of suitable location for SVC arid stabilizer signal tuning through eigenvalues and frequency response techniques. To determinate of suitable location for SVC, this paper used transfer function residues. Adequate oscillation damping is achieved by the use of stabilizing signals, designed through frequency response techniques and added to SVC. The study system is Benchmark System.

In this paper, neural network, which has learning capability, is used for fault type classification and fault section estimation for high speed relaying. The potential of the neural network approach is demonstrated by simulation using ATP. The instantaneous values of voltages and currents are used the inputs of neural networks. This approach determines the fault section directly. In this paper, backpropagation network(BPN) is used for fault type classification and fault section estimation and can use for high speed relaying because it determines fault section within a few msec.

High impedance fault can not be easily detected by conventional method. But if it would not be detected and cleared quickly, it can result in fires, and electric shock. In this paper, neural network, which has learning capability, is used for high impedance fault detector. The potential of the neural network approach is demonstrated by simulation using KEPCO's measured data. The instantaneous values and frequency spectrum of current are respectively used as the inputs of neural networks. Also, the methods using combined data to exploit the advantage of each data are proposed. In this paper, backpropagation network(BPN) is used for high impedance fault detector and can use for high speed relay because it detects faults within 1 cycle.

This paper proposes a new voltage control method of distribution substation using fuzzy inference. The aims of distribution voltage control equipments are reducing the operation frequency of lap changers and improving the characteristics of voltage(decreasing the errors between the actual voltage and the reference voltage). However, these objectives are in a tradeoff relationship. Conventional voltage control equipment does not have functions of judgement and prediction, so it turns up limitations of voltage control. Proposed voltage control method using fuzzy inference can improve voltage characteristics as it has those functions of judgement and prediction. This paper describes the design method of new voltage control method using fuzzy inference, simulates with simple voltage and current models, and compares decreased voltage errors with conventional voltage errors.

Kim, SungSoo;Kang, YongCheol;Nam, SoonRyul;Park, JongKeun;Myoung, SungHo;Kang, YoungSeok;Choi, HyoYeol 817
This paper presents an algorithm for calculation of harmonic distribution in distribution systems. In distribution systems, most state variables are not given explicitly. To calculate the harmonic distribution in distribution systems, state estimation is necessary. In this paper, power usage and harmonic current injection is estimated for each node from practically available data. The estimating procedure is illustrated by examples. 
This paper proposes a method for seeking the scheme of substation restoration by using genetic algorithm. Genetic algorithm (GA), first introduced by John Holland, is becoming an important tool in machine learning and function optimization. GA is a searching or optimization algorithm based on Darwinian biological evolution principle. As a test system, we assume a simple substation system and for the transformer fault, the result is obtained.

Park, YoungMoon;Park, JongBae;Won, JongRyul;Jhong, ManHo;Kim, JinHo;Choo, JinBoo;Jeon, DongHoon 823
This paper proposes a preventive maintenance scheduling system which is a userfriendly decisionmaking support system. The objective of the development of the package is to supply KEPCO's working experts with a useful tool for gaining a practical maintenance schedule. This program based on the MS Windows is made up of two main modules. The first is an interactive decisionmaking support module(IDSM). The main objective of this module is to provide various useful text and graphic information to users, and enable practicing engineers with sensitivity analysis of a targeting maintenance schedule. The second is a mathematical optimization module(MOM). In this module, the objective function of levelizing net reserve ratio with daily timeincrement is optimized using the relaxation method. 
Genetic Algorithm(GA) is a searching or optimizing algorithm based on natural evolution principle. GA has demonstrated considerable success in providing good solutions to many nonlinear, multidimensional optimization problems. The preventative maintenance scheduling is a kind of dynamic optimization problem with constraints. This paper applies GA to the preventative maintenance scheduling problem. In the case study, we can get the preventative maintenance scheduling of 3generators during 8 weeks using GA. It is shown that GA can be available to the preventative maintenance scheduling problem.

This paper is concerning on a study on the objectoriented programming and its application to maintenance scheduling. The concept of objectoriented programming enables us to modify and reuse software with much ease. By introducing objectoriented programming to maintenance scheduling, we can develop a hierarchical and reusable software in maintenance scheduling. The maintenance scheduling problem becoming more and more large and complex can be dealt with the concept of objectoriented technique and we hope this concept will give a reasonable solution. And evolutionary computation will be developed as a optimization technique.

This paper presents the research on the application of the Hopfield Neural Network to the Economic Load Dispatch problem. The ELD problem has convex cost functions as the objective functions, power balance equation and real power lower/upper limits as the constraints. So we have shown that the possibility of the application of the Hopfield Neural Network to the ELD problem. Through the case study, the simulation results are very close to the numerical method and the dynamic programming method.

In this paper, a method for the daily maximum load forecasting which uses a chaotic time series in power system and artificial neural network(Backpropagation) is proposed. We find the characteristics of chaos in power load curve and then determine a optimal embedding dimension and delay time. For the load forecast of one day ahead daily maximum power, we use the time series load data obtained in previous year. By using of embedding dimension and delay time, we construct a strange attractor in pseudo phase plane and the artificial neural network model trained with the attractor mentioned above. The one day ahead forecast errors are about 1.4% for absolute percentage average error.

Hopf and saddlenode bifurcation have been recognized as some of the reasons for voltage stability problems in a variety of power system models. Local bifurcations are detected by monitoring the eigenvalues of the current operating point. Therefore, many papers have used the methods using the eigenvalues. However, this paper discusses the bifurcations without calculating the eigenvalues as the system parameters vary In the 3 node system. Instead of calculating the eigenvalues, we use directly the coefficients of characteristic equation of Jacobian matrix. Also, the coefficients are used as stability index.

Kim, HakMan;Park, ChulWon;Jang, YoungNam;Shin, MyongChul;Lee, KwanHyo;Kim, SeungHyo;Roh, JaeHwa 841
This paper presents efficient protection countermeasure against lightning and surge for the control & instrumentation equipment using TVSS(transient voltage surge suppressor) and TEC(transient earth clamp). We propose the zone protection technique with TVSS and the use of TEC for clearing potential difference between frame ground and signal ground. 
This paper deals with a simulation method of faults in a power transformer. Using the [R],[L] matrix supplied by the auxiliary routine of EMTP called BCTRAN, the turn to ground fault and turn to turn fault are simulated and the inrush condition is simulated using saturable transformer model. Data from simulations can be used to identify the response of the digital protection algorithms for transformer.

As the power demands increases, one of the most important data is inside electric field of equipment in designing of insulators ami insulated wire for EHV distribution line. So far finite element analysis method is widely used to calculate this electric field. However as the shape of insulator becomes complicated, it is difficult in producing the mesh which suitable the shape. Especially, we have many difficulty that produce dense fine mesh only where the electric field is concentrated. Therefore in this paper, we perform the each conditional analysis of electric field using the Maxwell 3D Simulator to recover this defects. And we try to analyze electric field through the conventional 2 dimensional and 3 dimensional analysis in case of salt contamination on the surface of a insulator.

High impedance fault (HIF) is defined as fault that general overcurrent relay can't detect or interrupt, Especially when HIF occur under 15 kV, energized high voltage conductor results in fire hazard, equipment damage or personal threat. Because most HIF occur arc, HIF detection using arc is to increase. Numerical arc model can be applied in an electromagnetic transients program (EMTP) to reproduce the dynamic and random characteristic of arcs for any insulator arrangement, current and system voltage. It allows the representation of any network configuration to be investigated, so the digital simulation of arc faults through air can be substitute for demanding power arc test.

This paper describes the dissipation factor measuring techniques of insulating oil on the operating transformer by using digital signal processing. After applying voltage to the electrodes which is installed In a transformer, acquiring source voltage and current of electrodes and using crosscorrelation techniques. we can check the dissipation factor of insulating oil. To Improve measuring accuracy and the speed of process, we use hardware such as TMS320C31 DSP board and analog filter and software such as crosscorrelation techniques, rectangular window, and digital filtering techniques. We simulated the measuring accuracy and the degree of the noise effect of this new measuring techniques by using computer simulation, and compared the simplified measuring devices with schering bridge on degraded insulating oil. The result showed that this measuring technique can be used as diagnostic method on the pole transformers.

This paper describes a simulation model to analyze the interconnection operation of battery energy storage system(BESS) and utility system. The computer model used to these analysis composed by using PSCAD/EMTDC. The impacts experienced at load side are studied when occur faults in utility system, and also harmonics analysis are implemented. Results of these study are available to design the harmonic filter.

This paper presents the novel fault diagnostic expert system based on dissolved gas analysis(DGA) techniques in power transformer. The uncertainty of key gas analysis, norm threshold, and gas ratio boundaries are managed by using a fuzzy set concept. The uncertainty of rules are handled by fuzzy measures. Trend analysis through the monthly increment of key gas and DGA analysis are combined by the DempsterShafer theory, and the state of transformer and confidence factor are yielded by using this combined analysis. To verify the effectiveness of the proposed diagnosis technique, the expert system has been tested by using KEPCO's transformer gas records.

This paper presents a new approach to evaluate reliability indices of electric distribution systems using genetic algorithm(GA). The use of reliability evaluation is an important aspect of distribution system planning and operation to adjust the reliability level of each area. In this paper, the reliability model is based on the optimal load transferring problem to minimize over load generated load point outage in each subsection. This kind of the approach is one of the most difficult procedure which becomes a combination problems. A new approach using GA Was developed for this problem. We proposed a tree search algorithm which satisfied the tree constraint. GA is general purpose optimization techniques based on principles inspired from the biological evolution such as natural selection, genetic recombination and survival of the fittest Test results for the model system with 24 nodes and 29 branches are reported in the paper.

This paper presents the power system basic planning in urban area, when the superconductive power cable is installed in power system in the future. To decide the proper superconductive cable routes, load flow calculation was carried out based on the long term load forecasting of kyoungin area. The simulated results show that installation of superconductive power cable is able to overcome rapidly growing power demand of unban area.

This paper describes the faun phenomena by the simulation in power system including underground transmission power cable. Studying on fault phenomena is a very important part to decide the circuit breaker, protective relay and system configuration. Simulation was carried out in several different model system depended upon cable kinds using PSCAD/EMTDC, which is one of the transient program. The simulated results show the possibility to analyze transient phenomena for the cable system.

It is practically very important in multicriteria longtenn IRP process to develop the set of candidate resource plans that meet following two conditions. First, the number of resource plans should not be too large for computer job. Second, the unknown best plan should exist among the set of candidate plans. In this paper, several novel procedures are developed. The main idea of the procedures is the twostage approach. The first stage is to find the set of feasible resource capacity mixes in given target year(s). And, the second stage is to find the set of alternative paths of resource options for each resource mix determined in the first stage.

The KEPCO needs the review of the practice on the size of grounding wire, because the KEPCO has been experienced the melting failure of grounding wire many times. This paper proposes the appropriate standard and calculation conditions on the size of grounding wire for the cable system of transmission voltage class.

This paper discusses the definition and concepts, approach methodologies, capable application areas in electricity business, and tentative calculation of avoided generation costs based on the Korea's official longterm generation expansion plan. The objective to evaluate avoided costs of a resource is to supply decision makers with the breakeven cost of a targeting avoided resource. For the evaluation of avoided costs of the Korea's generation system, we consider the pseudoDSM option which has 1,000MW peak savings, load factor with 70 percent, and lifetime With 25 years as the avoided resource. The DSM resource can save the fuel and capacity additions of a electric utility during its life time. The capacity and fuel savings are evaluated from the two different cashflows with and Without the DSM option, which are generated on the basis of the generation system optimization model(WASPII), independently. The breakeven kWh costs of the DSM option over this 25year period is projected to be 34.1[won/kWh], which is composed of generationcapacity and fuel avoided costs with 101.139[won/kW] and 17.6[won/kWh], respectively.

Instead of pointtopoint hard wiring between substation yard equipments and SCADA RTU(Remote Terminal Unit), fibre optic cable will be used in the portion between Local Units and Central Unit in the future KEPCO 765kV substation. The connections between substation yard equipments and nearby Local Unit remain the same hard wiring. The new fibre optic system will provide security especially during ground faults and is immune to electrical noise. A prototype system will be manufactured and installed in the existing 154kV Yeosan Substation by the end of July this year and operated for one year. By incorporating the operation experiences acquired in the system, an improved system will be commercially applied to 765kV ShinAnSeong Substation where 345kV GIS will be installed initially and act as the switching station in the year 1998. The system is composed of one Central Unit and several Local Units. The Central Unit is composed of two workstation level computers, one is in operation and the other backup, and a Communication Control Unit. The Local Unit uses the existing SCADA RTU technology and takes the form of a distributed one. Between the Communication Control Unit and Local Units, the fibre optic system with starcoupler is used.

This paper presents Variance Reduction Techniques of the Monte Carlo Simulation considering NonExponential Distribution for Power System Reliability Evaluation. Generally, the components consisting of power system are assumed to be exponentially distributed in their state residence time. Sometimes, however, this assumption may cause a lot of errors in the reliability index evaluation. Nonexponential distribution can be approximated by a sum of several Erlangian distributions, whose inverse transform is easily calculated by using composition method. This paper proposes a new approach to deal with the nonexponential distribution and to reduce the simulation time by virtue of Variance Reduction Techniques such as Control Variate and Antithetic Variate.

This paper presents a method for optimal placement of series condenser in order to improve the power system transient stability using genetic algorithms(GAs). In applying GAs, this approach utilizes two kinds of strings, one is coded by a binary finitelength for the selection of lines to install series condenser, the other is coded by a real value for the determination of injected condenser capacitance. For the formulation. this paper considers multiobjective function which is the critical energy as decelerating energy in power systems and the total injected condenser capacitance. The proposed method is applied to 9bus, 18line, 3machine model system to show its effectiveness in determining the locations to install series condenser and the series condenser capacitance to be injected, simultaneously.

This paper presents the concept of the structure and major functions for the new EMS in KEPCO. This system will be in operation in the beginning of the 21 century in compliance with power system expansion and system architecture consists of distributed and open computer technology. The transmission operation control center as a backup control center of NCC will control under 345kV transmission system and regional control centers.

This paper presents the optimal operation scheduling of the private cogeneration system connected with auxiliary equipments. And the optimal size of auxiliary equipments is determined through evaluations of the minimum operation cost. The optimal operation scheduling is established by using the linear programming method. Simulation results show that the auxiliary boiler is operated as an economical facility but the thermal storage tank is used as a back up facility for emergency.

KODAS is made up of the Central Control System(CCS) as four Vax workstations linked up with LAN networks, six Substation Communication Control Units(SCCU) installed in substation to transfer data, 125 Feeder Remote Units(FRU) located at the lower position of automated switch to provide the information of Fault Indicator(FI) and three kinds of automated switches to have remote control functions such as SF6 gas feeder automation switch, recloser and gas insulated pad mountes switchgear for under ground line. This paper explains the functions and characteristics in detail about each devices mentioned above.

In this paper, we proposed the reasonable design standard and countermeasures of Demand Factor for large office buildings, that was made by the statistical way considering actual conditions, such as investicated electric equipment capacity, electric power consumption, etc. So as to save electric equipment investment, the decrease of power loss, the improvement of facilities utilization and the decrease of electric rates, we can be contributed by the application of the design standard. The result of saving effect is showed to confirm the practical use of the proposed Demand Factor, and also, it is believed that this proposed Demand Factor will be useful in electric equipment operation and planning.

Current design standard of substation grounding systems is primarily concerned with conventional outdoor substations. But in case of 154kV substations in the nation, almost all are indoortype GIS substations. So there became to be something not proper for application of present design standard to indoortype substations. In this paper, as a preliminary stage of drawingup of the grounding system design standard which concerned with indoortype substions, issues of current design standard are mentioned and directions of improvement are also presented.

The yearly load forecasting system has been developed for the economic and secure operation of electric power system. It forecasts yearly peak load and thereafter deduces hourly load using the topdown approach. Relative coefficient model has been applied to estimate peak load of a specific date or a specific day of the week. It is equipped with graphic user interface which enables a user to easily access to the system. Yearly average forecasting error may be reduced to
$2{\sim}3$ (%) only if we can forecast summertime temperature correctly. 
This paper proposes the proper phase arrangement of transmission lines for reducing the zero sequence circulating current. It is a wellknown fact that the zero sequence circulating currents are principally caused by the untranposed lines and numerical estimation method already has been established. In this paper, the circuit analysis for calculating the zero sequence circulating currents was performed on the existing 154kV fourcircuit systems of KEPCO and the proper phase arrangement was determined.

We have an urgent matter that is lack of energy resource. So we have to accomplish the design of economical energy utility systems and to develop energy facilities with high efficiency. Cogeneration system is one of them. It has high efficiency and can solve unbalanced electricity and heat demand in Summer & Winter concurrently. Recently, to increase the efficiency and stability of the total system, it is applying automatic control and monitoring software to the hardware facilities in industrial control systems. Therefore, these systems has been researched and developed in the advanced countries. It also has been researched and developed in the domestic since '60. But the control and monitoring software in cogeneration system has been hardly developed and has been imported expensive products from the advanced countries. In this study, we have developed the software of operating control, status monitoring, operating data managing and telecontrolling. We have confirmed usefullness of developed software by applying to gas turbine cogeneration system.

Koh, JaeHak;Cho, KyungLae;Ahn, BogChan;Won, HoiKwang;Lee, KwonHan;Cho, NamGook;Shin, HeeSeung 919
Recently, a growing demands on electricity require a high performance and reliable operation in the area of protection, control and monitoring of power plants and substations which may not provides with conventional systems. This paper describes a novel IDPACS (Integrated Digital Protection And Control System) in which we integrate all protection, control and monitoring function of the substations. The simulation results show that the proposed system provides fast response and reliable operation of power plant with superb performance on protection and control system. 
This paper presents the construction of Digital DAS system for supervising of power system simulator (KERISIM) which is developed in KERI. This system is composed of input transducer, input conditioner and digital supervisor. In order to watch P,Q,V,I, Power Factor and RMS in KERISIM successively, Digital arithmetic algorithm is accomplished to calculate Real/Reactive power from voltage/current data which is transferred by secondary part of CT/PT in simulator.

In this paper, we considers the problem of designing an observer for bilinear systems with unknown input. A sufficient condition for the asymptotic stability of the proposed observer is derived by means of delectability, invariant zeros, and stable subspace. In sufficient condition, the bound which guarantees the asymptotic stability was derived, which based on the Lyapunov stability. And Observer existing conditions are suggested in various cases. Through a simple example, we derived the observer structure and the bound which guarantees the asymptotic stability.

Some results and a nonlinear controller are proposed for feedback linearizable SISO systems with unknown constant parameters. It is shown that the systems which satisfy the proposed conditions can be transformed into a controllable linear subsystem with unknown parameter and it can be stabilized using the high gain nonlinear feedback linearizing controller. As an example for the proposed theorem, we introduce the single link robot with joint flexibility which is an well known example.

The simplifying method for the design of decentralized reduced order
$H_{\infty}$ controller is considered in this paper. When the controller is reconstructed for the original system, the decentralized condition of the controller for the transformed system is generally destroyed with older simplifying method. In designing the decentralized controller, direct output feedthrough terms give some difficulties by using other station's input information. We proposed a new solution for this problem. 
The
$H_{\infty}$ robust controller is designed for online adaptive control application by using polynomial approach. The$H_{\infty}$ robust controllers for adaptive system were designed first by Grimble. But they have a problem that two minimum costs can exist and did not minimize the conventional$H_{\infty}$ cost function which is the$H_{\infty}$ sum of weighted sensitivity and complementary sensitivity terms. In this paper, the two minimum costs problem can be avoided and the conventional$H_{\infty}$ cost function is minimized by employing the Youla parameterization and polynomial approach at the same time. In addition pole placement is possible without any relation with weighting function. 
This paper presents a stable learning algorithm for diagonal recurrent neural network(DRNN). DRNN is applied to a problem of controlling nonlinear dynamical systems. A architecture of DRNN is a modified model of the Recurrent Neural Network(RNN) with one hidden layer, and the hidden layer is comprised of selfrecurrent neurons. DRNN has considerably fewer weights than RNN. Since there is no interlinks amongs in the hidden layer. DRNN is dynamic mapping and is better suited for dynamical systems than static forward neural network. To guarantee convergence and for faster learning, an adaptive learning rate is developed by using Lyapunov function. The ability and effectiveness of identifying and controlling a nonlinear dynamic system using the proposed algorithm is demonstrated by computer simulation.

In this paper, we present an algorithm that allows tracking of a target using measurements obtained from a sensor with limited resolution. The Interacting Multiple Model (IMM) algorithm has been shown to be one of the most costeffective estimation schemes for hybrid systems. The approach consists of IMM algorithm combined with a coupled version of the Joint Probabilistic Data Association Filter for the target that splits into two targets.

In this paper, we consider a 2dimensional pursuitevasion game between a maneuvering target and a coasting missile using qualitative game theory. The optimal evasion algorithm of the target and the optimal guidance algorithm of the missile are determined and the barrier trajectories of this game are obtained through computer simulation. The optimal strategy of the missile and target is to turn toward the final line of sight direction using maximum input and maintain its direction. The capture set of the missile can be obtained by backward integration from the BUP.

The ultrasonic motor(USM) has good characteristics such as compact size, silent motion, low speed, high torque and high speed response. The USM is driven by 2phase AC electricity. The control parameters of USM are voltage, phase difference, frequency of input power, etc. In this paper, we propose voltage difference control. And we designed USM controller to adjust voltage and phase using pLSI(programmable Large Scale Integration). Voltage difference control has many advantages that are lower current, lower power than phase difference control. Especially there is nearly zero ampere at the zero point of speed and torque. we can apply this voltage difference control to the compliance control of DD manipulator.

For organizing a flexible and reasonable measuring system, it is necessary that one should not only understand the process itself but also choose an adequate system. In this paper, we want to show a system of measuring and analyzing diesel engine's performance which is capable of producing a report of a certain format as well as gathering, analyzing and managing data. The system was designed by VXIbus as an allinone. It was also proven by a real field test through the Guam diesel power plant, which was designed and constructed by Hanjung.

The moving vehicle with disturbances has the 6 dof motion in the pitching, yawing and rolling directions of two independent axes. The control system in such a moving vehicle has to perform disturbance rejection well. The paper presents PID controller with disturbance rejection function, low sensitivity filter and notch filter for the bending frequency rejection. The performance of a designed system has been certified by the simulation and experiment results.

In this paper, we study the modeling and control of ElectroMagnetic Suspension System with 2 Degree Of Freedom. While the previous researchers considered the control of single rail EMS Systems, we consider the control of two rail EMS Systems. We first derive a simple model to represent the dynamics of EMS System with 2 D.O.F., using the Lagrange's method. The nonlinear equations of motion that we derive are shown to be linearizable by coordinate change and nonlinear static state feedback. The nonlinear static state feedback controller is constructed explicitly.

A conventional PI controller does not provide a proper response in face of various kinds of load variation. In this paper, three types of fuzzyPI hybrid control scheme are proposed in order to improve the performance of the PI controller. The proposed control schemes are applied to the speed controller of AC servo motor systems. The effectiveness of the proposed methods is shown by computer simulation and the advantage of each control scheme is discussed.

This paper presents fuzzy control rules for automatically driving a model car. The model car has a two sensors. This sensors measure a road outline and get a distance between a model car and a road outline. A Fuzzy Logic Controller(FLC) bases on a knowledge of the human experience. A FLC designed successfully controls the model car. Simulations results verifies the validity of proposed algorithm.

In this paper, Modified GPS Kalman filter algorithms which allow user to estimate its position when the number of visible GPS satellites becomes less than four are presented. They are derived using the previous estimation of altitude and clock bias. Thus, it is possible to estimate 3dimensional user position even when only two GPS satellites are visible. The algorithms are ideally suited to car navigation in urban areas where lack of GPS visibility is the major problem because of the frequent blockage of the GPS signals by tall buildings and other structures. Simulation results in this paper show that modified GPS Kalman filter provide better performances than a general GPS Kalman filter or any other instantaneous GPS solution algorithm, especially in the case which the number of visible GPS satellites becomes less than four.

In this paper, a reference model following control system using a fuzzy logic controller(FLC) is proposed By using an integrator and a nonlinear hysteresis element, a reference model whose response has no overshoot and fast rise time is designed. A FLC is designed to follow as close as possible to the response of the reference model. The proposed design method is shown that the robustness and the optimal tracking property can be achieved under modeling error, disturbance and parameter perturbations. The effectiveness of the proposed design method is verified through the simulation that compare using the FLC with using a
$H_{\infty}$ controller. 
This paper presents an algorithm to control the undesirable sway of a suspended load in the crane system that has a tradeoff between positioning the load and suppressing the sway of the load. The aim is to transport the load to a specified place with small sway angle as quickly as possible. Dynamic model is based on a simple pendulum driven by a velocity drive that is mostly used for actuating a trolley in industry. Proposed algorithm is composed of two parts : one is a offline optimal trajectory generator, the other online tracking control. The former produces optimal trajectories minimizing energy under the speed constraint of velocity drive. The latter controls outputs to track the generated trajectories. Digital simulations and experiments are performed on a pilot crane to demonstrate the performance of the proposed control algorithm.

This paper presents the method of determining state feedback gains of XPTOS for disk drive servomechanism based BESSEL filter prototype. A typical disk drive actuator can be modeled as second order dynamics for low frequencies. However, the response at higher frequencies shows resonant behavior which cannot be easily modeled. XPTOS consists of the nonlinear control region and the linear control region. In the linear control region, the poles of a second order nominal model of plant must be properly relocated by pole placement technique to attenuate resonant modes at high frequency and to attain minimum time state transition. It is difficult to select position to satisfy this object because velocity feedback gain is subjected to position feedback gain in XPTOS. Here poles of BESSEL filter prototype are selected to determine state feedback gains of XPTOS. Simulation results for disk drive servomechanism using XPTOS having state feedback gains by the proposed method are presented.

In the power and communication cable production, automation is essential in order to reduce the cost and enhance the productivity. In this study, we propose an automatic cable rolling system and add a scheme to deal with noise disturbance.

This paper presents feedback control?method of educational robot made up of step motor by specific TinyC at PPI 8255 board of pocketcom(pocket computer; PCE200). Machine language capacity of TinyC compiler(Ver 1.0) is about 22kbyte, and so it is easily transmitted from personal computer to pocketcom of conventional memory 32 kbyte. This experimental results show that TinyC control programs are practised on the pocketcom connected to PPI 8255 board for educational robot and XY plotter, and these are presented to show the effectiveness of the proposed algorithm.

The design of I/O scaling factors for fuzzy controller system is proposed in this paper. The proposed method is for nonlinear input scaling factor and variable output scaling factor. The fuzzy controller is evaluated by computer simulation on the 1st order process and 2nd order process. Simulation results showed robust characteristics for variable reference signal.

This paper proposes an adaptive FilteredX LMS algorithm with robustness. The proposed system updates filter parameters to keep the performance even if the conventional Active Noise Control (ANC) system well does not work. As a result of the computer simulation, the proposed system has all the advantage of the system using the conventional FilteredX LMS algorithm. Also some results from the proposed algorithm present that the system is stable when the Adaptive filter does not work. Therefore, the proposed system using the Adaptive FilteredX LMS algorithm must have much advantage than the system using the conventional algorithm in the side of the stability and performance.

This paper shows how the
$H_{\infty}$ control problem of singular nonlinear systems via output feedback can be solved. The solution of the problem is shown to be related to the existence of solutions of a pair of HamiltonJacobi inequalities in n independent variables, which are associated with slate feedback and output injection design. Our approach yields to a set of sufficient conditions under an extra assumption. This conditions are in terms of a set of HamiltonJacobi Inequalities parameterized by adequately small parameters. 
In this paper, we represented the relation of minimum entropy/
$H_{\infty}$ controller and mixed$H_2/H_{\infty}$ controller. An$H_2$ controller design problem involving a constraint on$H_{\infty}$ disturbance attenuation is considered. By the equivalence of the mixed$H_2/H_{\infty}$ control problem and the minimum entropy/$H_{\infty}$ control problem, we presented the controller statespace realization. Decentralized case was illustrated briefly. 
In this paper, presented are the results of observability analysis for the vehicle maneuver during InFlight Alignment of SDINS. The target system for observability analysis is 10th order one. Three trajectories for IFA are considered. To analyze the observability of the time varying system, correlation coefficient is used and to measure the degree of observability of the given system, simulation is carried out using covariance matrix. The results of simulation show that trajectories which are having continuous changes in attitude and acceleration of system is superior to straight trajectory in correcting navigation errors.

일부궤한 제어시스템이 안정화되는 비례보상기의 이득의 구간을 연구한다. 이 논문에서 제어시스템이 연결된 구간에 대하여 안정화되는 조건을 구한다. 연결된 구간은 그 구간에 있는 어떤 임의의 두 실수를 취할 때 두 실수 사이의 모든 실수가 그 구간에 속하는 경우를 말한다. 조건은 페루프 전달함수의 분자나 분모의 주파수를 매개변수로한 부등식으로 표현된다. 또한 이산 시간 제어시스템과 시간지연 연속시스템에 관한 조건도 구한다.

This paper presents an approach to building multiinput and singleoutput fuzzy models for nonlinear databased systems. Such a model is composed of fuzzy rules, and its output is inferred by simplified reasoning. Optimal structure and membership parameters for a fuzzy model are automatically and simultaneously identified by GA(Genetic Algorithm). Numerical examples are provided to evaluate the feasibility of the proposed approach. Comparison shows that the suggested approach can produce a fuzzy model with higher accuracy and a smaller number of fuzzy rules than the ones achieved previously in other methods.

This paper proposes a realtime OFT implementation technique which is based on the finitebit approximation of the DFT coefficients. The effect of the approximation is analytically investigated and its result is obtained in the form of an equation of noise to signal ratio. The analysis result is confirmed by comparing it with those of the computer simulation and the actual experiment for human sleep EEG data.

This paper investigates the chaos secure communication with RLCG transmission line. The synchronization of chaos in two coupled Chua's circuit with RLCG transmission line systems are also studied.

In this paper, when a robust active noise controller for a small cavity to control the noise induced in the cavity is designed, the Graphical method based on the robust stability and performance requirements is studied. The problem of designing controller that achieve these robust performance conditions is related to minimizing the
$H_{\infty}$ norm of the mixed sensitivity function by using$H_{\infty}$ control theory. Also, For design the controller, the loopshaping method which control the weight functions to satisfy the design specification without loss of a robust performance can be used. Therefore, we determined the acceptable design specification with the system characteristics of the small cavity and obtained its robust controller with the robust performance specifications by stability margin. 
This paper proposes a design of selftuning fuzzy rules and membership functions based on genetic algorithms. Suboptimal fuzzy rules and membership functions are found by using genetic algorithms. Genetic algorithms are used for tuning fuzzy rules and membership functions. A arbitrary speed trajectories are selected for the reference input of the proposed methods. Experimental results show the good performance in the DC motor control system with the selftuning fuzzy controller based on genetic algorithms.

Sources of nonlinearity In a fuzzy logic controller Include the fuzzification, the fuzzy reasoning and the defuzzification. In this paper, a closed form expression for the defuzzified output is derived in case of a fuzzy logic controller with two Inputs, triangular memberships, MacVicarWhelan type linguistic rules, and direct fuzzy reasoning. As a result, it is shown that fuzzy logic controller is a nonlinear controller. Also its nonlinearity Is analyzed with respect to the conventional PID control and the sliding mode control.

The purpose of this study was to develop systematic diagnostic system testing easily, rapidly vestibular function of patients suffered from vestibular syndrome such as nausea vomiting, dizzness, ataxia. Diagnostic system composed of rotatory chair system which rotated sinusoidally patients against their vertical axis for purpose of invoking eye movement by vestibuloocular reflex and the softwares which storaged eye movement into computer and analyzed eye movement. Rotatory chair system consisted of comfortable chair and DC servomotor with reducer(1:80) by controlled servo in field of nonlinear motor control, double feedback loops system containing velocity feedback loop and position feedback loop was applied to this sever controlled rotatory chair system. Maximum rotatory velocity of rotatory chair was upto 60 degree per second and frequency range was 0.01 to 0.64 Hz. These above results suggest that clinical rotatory chair system may test easily, rapidly vestibular function and diagnose etiology of dizziness, thus giving effective assistance on the treatment of dizziness patients.

Now is an automation age. Therefore it is required that machine can do work which was done by men. Artificial Neural Network was developed by the necessity of this purpose. This paper shows a Predictive Control with a Neural Network. The Neural Network learns an Inverted Pendulum in various situations. Then, it has a power to predict the next state after accept the current state. And the Neural Network directs the BangBang Controller to give input to a plant. It seems like that a human expert looks the state of a plant and then controls the plant. It is used a Feedforward Neural Network and shown control state according to the learning. We could get a satisfactory results after complete learning.

In this paper, an adaptive fuzzy logic controller is presented for autotunning of the scaling factors by using learning capability of neural networks. The proposed scheme consists of the FLC which includes the PItype FLC and PDtype FLC in parallel form and the neural network which learns scale factors of FLC. Computer simulations were performed to illustrate the effectiveness of a proposed scheme. A proposed FLC controller was applied to the second order system and velocity control of the brushless DC motors. For the design of the FLC, tracking error, change of error, and acceleration error are selected as input variables of the FLC and three seal e factors were used in the paralleltype FLC. This scheme can be used to reduce the difficulty in the selection of the scale factors.

Inputoutput linearization technique in nonlinear control does not guarantee the robustness in the presence of parameter uncertainty or unmodeled dynamics, etc. However, it has been used as an important preliminary step in achieving additional control objectives, for instance, robustness to parameter uncertainty and disturbance attenuation. An indirect adaptive control scheme based on inputoutput linearization is proposed in this paper. The scheme consists of a Hopfield network for process parameter identification and an adaptive sliding mode controller based on inputoutput linearization, which steers the system response into a desired configuration. A numerical example is presented for the trajectory tracking of uncertain nonlinear dynamic systems with slowly timevarying parameters.

The use of fuzzy theory in task of pattern recognition may be applicable gases and odours classification and recognition. This paper reports results obtained from fuzzy cmeans algorithms to patterns generated by odour sensing system using an array of conducting polymer sensors, for volatile chemicals. For the volatile chemicals clustering problem, the three unsupervise fuzzy cmeans algorithms were applied. From among the pattern clustering methods, the FCMAW algorithm, which updated the cluster centres more frequently, consistently outperformed. It has been confirmed as an outstanding clustering algorithm throughout experimental trials.

For the precision positioning and tracking control, the proper friction compensation is essential. The friction causes steady state error. The friction compensation based on the velocity and the controlling input or the desired velocity provides limited performance if the compensation value is fixed. In this paper, a friction compensation scheme using a fuzzy logic is proposed. The friction compensation amount is adjusted depending on the velocity and controlling input. The proposed fuzzy friction compensator with a poleassignment controller is implemented in a linear positioning system. To illustrate the effectiveness of this scheme, computer simulations and experiments are carried out for the cases of no friction compensation, the proposed fuzzy friction compensation, and another friction compensation scheme based on velocity and control input, and the results are compared with each other.

This paper presents a neurocontrol algorithm for the speed control of a direct drive motor without the knowledge of the dynamics of the motor and the characteristics of a nonlinear load. In the field of motor control, it is not possible to directly use the backpropagation method in order to train a network since the desired output of the network is not known. Hence, we propose an extended backpropagation algorithm to force the closed loop system to give desired results. Experimental results shown that the proposed neurocontroller can reduce the unknown load effects and have the good velocity tracking capabilities.

This paper proposes a Fuzzy TPR having the control function to a TPR used for the conversion of electricity in industrial field. The Fuzzy TPR based on the Fuzzy Logic Control technique is composed of the parts to calculate the lowlevel value and the highlevel value. These values are calculated by error and change in error which are refer to the lookup table. To show the usefulness of the proposed Fuzzy TPR, it is applied to industrial temperature control system. In the results of experiment, we see that the system is able to fast reach steadystate, and for our approach to be robust to external disturbance than the method using the conventional TPR.

In this study, a new OSA controller is proposed for controlling discretetime chaotic systems efficiently. A new OSA controller uses NARMAX models, and its feedback gain is designed on the basis of conventional linear control theory. In order to evaluate the performance of a new OSA controller, a new OSA controller is applied to Henon system which is a discretetime chaotic system, and then the control performance of a new OSA controller are compared with that of the previous modelbase controller through computer simulations.

This paper presents a discrete adaptive observer for MIMO system of an IM model in DQ reference model. The IM model in the stationary frame is discretized and it is transformed into the canonical observer form. The unknown parameter is choosen as rotor speed. The adaptive law for parameter adjustment is obtained as a set of recursive equations which are derived by utilizing an exponentially weighted normalized leastsquare method. The proposed adaptive observer converges rapidly and is also shown to track timevarying plant parameter quickly. Its effectiveness has been demonstrated by computer simulation.

As PLC has become central to today's FA environment, the importance of developing and providing specialmodule of PLC such as Analogmodule, PIDmodule, Temperature Controlmodule has increased. In this paper introduces the Temperature Controlmodule which is developed by LGIS R&D lab. and presents the availability of PLCcontrol system with Temperature Controlmodule.

This paper concerns about the active noise canceller via filteredX LMS algorithm. There are various kinds of algorithms to implement a active noise canceller. Traditional LMS algorithms are not enough to implement a sharp noise cancellation characteristics. We simulates a filteredX LMS algorithm and implements an algorithm to the TMS320C5x DSP processor and shows that result.

In modern control engineering, the model following system is a typical method. The model following system's performance is due to algorithm of control law, accuracy of modeling to the plant, and dynamics of the reference model. But the determination of the reference model depends on knowledge of an expert. Using an expert system, the determination method of the reference model was proposed in this paper. So, the reference model can be selected by user who has no Knowledge of dynamics and parameters.

This paper presents a neuro fuzzy system(NFS) for implementing fuzzy inference system with a monotonic membership function. The modeling and control of a discrete nonlinear system using a NFS is described. The membership function parameters of a identifier and controller are adjusted by backpropagation algorithm. These identifier and controller is constructed to proposed NFS. A online identification and control are accomplished by this NFS. A controller is gived information of the system, that is variation of the system output according to that of the control input by a identifier. A controller makes control input in order to control discretetime nonlinear system. A Simulation is presented to demonstrate the efficiency of a suggested method.

In this paper, we design the robust controller for MIMO system using multiple fuzzy logic controller. Based on the knowledge of system input/output data, we introduce the simple adaptation laws to approximate the decoupling matrix from input channel to output channel. The proposed control algorithm is applied numerical example.

To automate an excavator the control issues resulting from environmental uncertainties must be solved. In particular the interactions between the excavation tool and the excavation environment are dynamic, unstructured and complex. In addition, operating modes of an excavator depend on working conditions, which makes it difficult to derive the exact mathematical model of excavator. Even after the exact mathematical model is established, it is difficult to design of a controller because the system equations are highly nonlinear and the state variable are coupled. The objective of this study is to design a fuzzy logic controller(FLC) which controls the position of excavator's attachment. This approach enables the transfer of human heuristics and expert knowledge to the controller. Excavation experiments are carried out to check the performance of the FLC.

Controlling chaos is a new concept, which transform chaotic signal to fixed points, or low periodic orbits. In this paper we propose state feedback method in order to control chaotic signal in canonical Chua's circuit Canonical Chua's circuit is a simple electronic circuit consists of two linear resistors, a linear inductor, two linear capacitors, and only one nonlinear element so called Chua's diode. This nonlinear element supplies power to the circuit and drives the chaotic oscillations. Proposed control method is successful to control chaotic signal in canonical Chua's circuit Result shows that chaotic trajectory change rapidly its orbit to stable fixed points, 1 periodic orbit, or 2 periodic orbit when control signal applies.

A number of recent paper have investigated the feasibility of synchronizing chaotic system. In this paper we proposed the chaotic synchronization of the canonical. Chua's circuit with RLCG transmission line by driveresponse system. We expect that proposed method is available to secure communication with RLCG transmission line.

This paper presents a design method of Kalman Filter on continuous nonlinear stochastic system via BPF(Block Pulse Function). When we design Kalman Filter on nonlinear stochastic system, we must linearize this systems. In this paper, we uses the adaptive approach scheme and BPF for linearizing of nonlinear system and solving the Riccati differential equation which is usually guite difficult. This method proposed in this paper is simple and have computational advantages. Furthermore this method is very applicable to analysis and design of Kalman Filter on nonlinear stochastic systems.

In this paper The tuning of PID controller for multi inputoutput is studied by using fuzzy inference. State of coupling is estimated by fuzzy inference, its results is used for tuning of PID controller to get optimum P,I,D parameter with regard to state of coupling. This method is simulated to Turbogenerating system with
$2{\times}2$ multi inputoutput and made with electronic circuit, its response is very satisfactory. 
In this paper, the eddy current flowmeter with 4coil is designed and made on the basis of theory, and its characteristics is considered through dry test and flow experiments. The biggest output signal varied with wave wave form frequency, and 900Hz in rectangular wave, 27.12kHz in sine wave. The conductivity is bigger, the output signal is bigger and has a linearity between both relation, and also The Magnetic Reynolds Number and output characteristics The flow faster and the output signal is bigger.

A wellknown problem in adaptive control is the poor transient response which is observed when adaptation is initiated. This paper proposes a useful method to improve the transient response of adaptive control systems by using multiple models of the plant and switching mechanism by fuzzy inference. The models are identical except for initial estimates of the unknown plant parameteres. The control input to be applied is determined at every instant by the model which best approximates the plant. Simulation results are presented to indicate the performance improvement of adaptive control systems using the proposed method.

In this paper, a hierarchical fuzzy controller is proposed for the stabilization control of the inverted pendulum system. The design of controller for that system is difficult because of its complicated nonlinear mathematical model with unknown parameters. Conventional fuzzy control strategy based only on dynamics of pendulum made have failed to stabilize. However, proposed control strategies are to swing pendulum from natural stable up equilibrium point to an unstable equilibrium point and are to transport a cart from an arbitrary position toward a center of rail. Thus, the proposed fuzzy stabilization controller have a hierarchical fuzzy inference structure; that is, the lower level is for inference interface for the virtual equilibrium point and the higher level one for the position control of cart according to the firstly inferred virtual equilibrium point.

In this paper, we discuss the automatic recognition system of vehicle types and licence plate numbers using artificial neural networks, which will be used as vehicle identifier. We confine to expose the vehicle licence number for violating bus lane and stolen cars. Therefore, the vehicle height, width and distribution profile are used as the feature parameters of vehicle type. This system is composed of two parts: one is an image preprocessor of vehicle images and the other one is a pattern classifier by neural networks. The experimental results show that our method has good results for the recognition of vehicle types and numbers.

In this paper, we propose a new approach for robust autotuning of PID gains using Evolution Strategy. Evolution Strategy is searching algorithm which imitate the principles of natural evolution as a method to solve parameter optimization problem and easy to use without any other special mathematical theory. Through the simulation of the speed control of a seriesconnected de motor, our proposed method shows more improved performance by finding optimal parameters of PID controller than a classical ZieglerNichols method.

The servo system requires faster and more accurate dynamic responses. A new technique for the position control of DC servo motors is presented in this paper. The proposed technique employs a Self Tuning Regulator Proportional Integral Derivative(STR PID) position control systems in order to improve the dynamic performance of a DC servo motor. Recursive least squares (RLS) method is used in order to estimate the STR PID coefficients,
$K_P$ ,$K_I$ , and$K_D$ . In order to consider dynamics such as voltage, angular velocity, and rotor angle, the above method was applied position control system. 
This paper designs a digital controller by making use of the
$H^{\infty}$ control algorithm and$\mu$ synthesis in order to keep a balance of the VTOL(Vertical Take Off and Landing Plane) vehicle with 4 fans. A identification of the actual model is acquired by the vehicle rolling, pitching and yawing angles for a pseuderandom signal input and various identification theories. In spite of parameter variations and existing disturbances, the designed controller showes its robust performance through simulations and experiments. 
The main purpose of this study is to achieve the effective port works by using of containercrane, to disposer of many containers rapidly by using of vision sensor in order to control the swing of spreader. It is examined the possibility of automation in containercrane through a test in the field.

Depth between the robot and the target is an essential information in the robot control. However, in case of eyeinhand robot with one camera, it is not easy to get an accurate depth information in realtime. In this paper, the techniques of depthfrommotion and depthfromfocus are combined to accomplish the realtime requirement. Integration of the two approaches are accomplished by appropriate use of confidence factors which are evaluated by fuzzy rules. Also a fuzzy logic based calibration technique is proposed.

Monitoring system is essential part in control system to monitor the circumstances of the industrial equipments. Color graphics is generally introduced in the monitoring system for the purpose of effective human interfaces. Hence, color graphic editor is under the implementation to draw graphic elements easily which are utilized in the monitoring situation. In this study, OOP(object oriented programming) is applied in the programming of the software. OOP enables systematic design of algorithm, easy management of the software and easy extension of additional functions. It is reported that the software is under the implementation. Therefore, preliminary structure of the software is briefly discussed in this paper.

A canonical form observer design method for nonlinear systems is studied. Through this method, an observer of single link robot system with flexible joint is proposed. It is shown through simulation that the system can be stabilized when using the nonlinear feedback linearizing controller and the supposed observer.

In this paper, we consider the mixed
$L_1/H_{\infty}$ problems of finding internally stabilizing controllers which minimize the peaktopeak gain of a certain closed loop transfer function with$H_{\infty}$ norm constraint on other closed loop transfer function(or vise versa). This problem is a useful framework for designing a controller with the norm constraints upon time and frequency domain. We formulate the mixed$L_1/H_{\infty}$ problem as LMI problems by using the reachable set. This paper offers the sufficient condition for the existence of suboptimal state feedback controller, and shows that suboptimal solution can be obtained by solving a finitedimensional convex optimization and a line search. 
A necessary and suficient conditions is proposed for feedback linearizable SISO systems with unknown constant parameters. It is shown that the systems which satisfy the proposed conditions can be transformed into a controllable linear system with unknown parameter and it can be stabilized using the nonlinear feedback linearizing controller. We also present the analysis and implementation of a nonlinear feedback linearizing control for an ElectroMagnetic Suspension (EMS) system. We show that an EMS system is nonlinear feedback linearizable and satisfies the proposed conditions, and hence that the proposed nonlinear feedback controller for an EMS system is robust against mass parameter perturbation and force disturbance.

Feedback Linearization technique needs the exact cancellation of nonlinearity which restricts its application to real environment. To overcome these shortcomings, Highpin feedback is good remedy to this problem. In this paper, we briefly survey the highgain feedback control technique and show some conditions for applying this method to nonlinear systems. In order to use this technique in real situation, some properties of
${\varepsilon}$ bound and semiglobal stabilization are discussed. 
In this paper, a fixedhorizon
$H_{\infty}$ tracking control (HTC) for continuous timevarying systems is proposed in statefeedback case. The solution is obtained via the dynamic game theory. From HTC, an intervalwise receding horizon$H_{\infty}$ tracking control (IHTC) for continuous periodic systems is obtained using the intervalwise strategy. The conditions under which IHTC stabilizes the closedloop system are proposed. Under proposed stability conditions, it is shown that IHTC guarantees the$H_{\infty}$ norm bound. 
In this paper, we consider a nonlinear control problem for an ElectroMagnetic Suspension(EMS) system with flexible rail. In controller design based on feedback linearization, we apply the feedback linearization technique to the part of the system which provides nonlinearities to the plant. The experimental results demonstrate that the feedback linearization controller shows good performance.

In this paper, uncertain parameters of the heat transfer model of a Dynamically Tuned Gyroscope (DTG) are estimated by the Recursive Least Squares (RLS) method. Also, using this model, a temperature controller for a DTG is designed. As the temperature controller, a PI controller is used. It is presented that a controller can be easily designed when the heat transfer model of a DTG is used. By simulations and experiments, it is shown that the estimated heat transfer model is appropriate and the desired performance of the temperature controller is satisfied.

In the last several years, considerable attention has been focused on the problem of designing observers for linear systems with unknown inputs. Since UIO(unknown inputs observer) has the derivative of the outputs, it is very sensitive to measurement noises. Therefore this note propose an algebraic approach to UIO design to alleviate the prescribed problems. Since the proposed method has simple form to estimate state and unknown input and robustness to sensor noise, we believe that it is very attractive in practice.

In power transformers, vibration occurs at winding, core and case due to current, voltage, temperature changing and winding reformation. Winding deformation and change of vibration signals are occurred due to electromagnetic force induced by fault current. In this paper, in normal and fault states, the trends of fundamental waves and higher harmonics are considered. To inspect the factors that affect the fundamental waves and higher harmonics, the trends are considered with varying voltage and load. Determination functions are generated and applied to signals so that normal and fault state are determined by determination functions.

In this paper, the direct adaptive control using neural networks is presented for the control of chaotic nonlinear systems. The direct adaptive control method has an advantage that the additional system identification procedure is not necessary. Two direct adaptive control methods are applied to a Duffing's equation and the simulation results show the effectiveness of the controllers.

In this paper, the optimization of fuzzy controller using genetic algorithm is studied. The fuzzy controller has been widely applied to industries because it is highly flexible, robust, easy to implement, and suitable for complex systems. Generally, the design of fuzzy controller has difficulties in determining the structure of the rules and the membership functions. To solve these problems, the proposed method optimizes the structure of fuzzy roles and the parameters of membership functions simultaneously in so offline method. The proposed method is evaluated through computer simulations.

In this paper, a simulator is designed along with S/W package for crane controllers. Due to trolley's acceleration or deceleration, cranes inherently cause swing motion of the objects in transporting heavy objects. This swing not only deteriorates the crane handling safety but also increases the processing time. To overcome these drawbacks, the fuzzy rulebased simulator is developed with inhibitory swing at final action. The computer simulation shows that the swing at initial and final positions is removed fast with small position error. The proposed simulator can be used for handling object stablely and the study of effectiveness in unmanned operation of cranes.

This system is an unified Digital Generator Controller. It has an Electronical Generator Sequencer which control the sequence of a generator, an AVR(Automatic Voltage Regulator) which perform the regulation of generator terminal voltage optimally to user's needs, and an Auto Synchronizer, it can switch the power source on from generally used an the generator to load automatically. It also possesses a Battery Charger which charge a storage battery to appropriate voltage level. Here we describe it's configuration, specifications, the way of control, figure, functions and waveforms.

As electrical discharge machinery(EDM) is industrial process which is manufactured by discharge energy, by producing discharge, EDM process finished material at the little micrometer air gap. Especially, EDM is used for the characteristic of heatresisting material, it puts to use airspace industrial element, confusing shaping material such as jet engine, rocket elements. Working performance. is changed by environment of working, discharge current voltage and duration of discharge pulse. Evaluation of performance working is work speed, clearance smoothing of product surface, wasting of pole. In this paper, this machine is compensated by adaptive controller which corrects the weak points of classical machine which is observed and operated working condition by user in hands. The previous purpose is main object in this thesis. The adaptive controller automatically detect abnormal condition and working conditions. To improve performance, surface smoothing and working speed, the adaptive controller uses fuzzy control strategy. To evaluate performance, this controller is implemented by microprocessor i80c196 and is applied real experimental machine.

Analogdigital converter boards for use in personal computers have recently being improved markedly, many kinds of high speed(1 MHz  10 MHz sampling rale) and over 12bit vertical resolution A/D boards released. It can be applicable to high frequency magnetic measurements. In measurement of magnetic properties of high frequency, digitizing oscilloscope or trasient recorder are being used. but, those price are often expensive, we constructed PC controlled AC BH loop tracer that can measure Bs, Br, He, permeability and may be applied about 100 Hz  20 kHz range. it use IBM PC compatible 1 M Sample/s, 12 bit A/D converter board with SSH(Simultaneous Sample and Hold).

This paper describes a driving simulator for the multimotor driven electric vehicle. The electric vehicle is simulated by a 7DOF(degree of freedom) model and a couple of developed split torque control algorithms are tested with the simulator to illustrate and verify its normal operation.

QFT(Quantitative feedback theory) is a design method to synthesize robust controller, satisfying some design specifications. Loop shaping is regarded as one of the important steps in QFT design. In this paper, we present to apply the approximation algorithm for loop shaping to PID tuning. An example is used to illustrate its feasibility.

In this paper, method for direct adaptive control of discrete nonlinear systems using neural network is presented. Also, the stability problems are investigated in sense of the Lyapunov stability conditions. Through extensive simulation, the SOON is shown to be effective for indirect adaptive control of nonlinear dynamic systems.

The objective of this paper is to control a nonlinear dynamical systems based on SelfOrganized Distributed Networks (SODN). The learning with the SODN is fast and precise. Such properties are caused from the local learning mechanism Each local network learns only data in a subregion. Methods for indirect adaptive control of nonlinear systems using the SODN is presented. Through extensive simulation, the SODN is shown to be effective for adaptive control of nonlinear dynamic systems.

Neural networks and fuzzy systems have attracted the attention of many researehers recently. In general, neural networks are used to obtain information about systems from input/output observation and learning procedure. On the other hand, fuzzy systems use fuzzy rules to identify or control systems. In this paper we present a generalized FCMAC(Fuzzified Cerebellar Model Articulation Controller) networks, by integrating fuzzy systems with the CMAC(Cerebellar Model Articulation Controller) networks. We propose a direct adaptive controller design based on FCMAC(fuzzified CMAC) networks. Simulation results reveal that the proposed adaptive controller is practically feasible in nonlinear plant control.

In this paper, a fault diagnosis method is proposed for selfdiagnostics of PLC(Programmable Logic Controller), process controller in industrial fields, and diagnosis of its external devices such as sensors and actuators. The aim of this research is proposition of systematic method of fault diagnosis of PLC control system and development of its equipment. A PLC fault diagnosis algorithm consists of selfdiagnostics given by PLC makers, Inpuot/Output tracking method by analyzing sequence PLC programs, searching method of past fault cases in database using an expert system, and diagnosis of PLC units such as CPU, DI, and DO board. Finally usability of PLC fault diagnostic system is verified by testing a MELSEC PLC.

For an automatic steering problem of vehicles, the main task is to keep a reference path with assumption that the displacement from the guideline can be measured by a sensor. In this paper, a sliding mode fuzzy logic controller design method is introduced and it shows highly enhanced performance in comparison with the other results. The method can be relatively simply implemented.

It is well known that the controller output limits have a significant effect on the closed loop system performance. GPC has many tuningknobs which can he used to minimize actuator activity. Especially, increasing the control weighting
$\lambda$ cuts down the controller output variance. Using this property, we propose the GPC with Input constraints(GPCIC) which is based on the relation between control weighting$\lambda$ and optimal solution of the unconstrained GPC. The GPCIC algorithm is the calculation of the optimal$\lambda$ such that the output of the unconstrained GPC is satisfied with the rate Ind the level constraint. 
To Provide pleasant building environment and the ease of maintenance and facility management, many new office buildings are being built as intelligent buildings. Building control systems which are employed in intelligent buildings require advanced types of controllers and varieties of control schemes. Designing and installation of these types of advanced building control systems take a lot of effort and also they are costly. In order to design these systems, it is necessary for the designers to have means to analyze and estimate the performance of control systems. In this paper, the results of the simulator for HVAC and elevator system are presented as the first stage of the development of the integrated simulator. For the development of simulator, ARENA which is the generalpurpose software tool for the simulation with reinforced GUI is used.

The computedtorque method (CTM) shows good trajectory tracking performance in controlling robot manipulator if there is no disturbance or modelling errors. But with the increase of a payload or the disturbance of a manipulator, the tracking errors become large. So there have been many researchs to reduce the tracking error. In this paper, we propose a new control algorithm based on the CTM that decreases a tracking error by generating new reference trajectory to the controller. In this algorithm we used a fuzzy system based on the rule bases. For the numerical simulation, we used a 2link robot manipulator. To simulate the disturbance due to a modelling uncertainty, we added errors to each elements of the inertia matrix and the nonlinear terms and assumed a payload to the endeffector. In the simulations of several cases, our method showed better trajectory tracking performance compared with the CTM.

In this paper, an efficient and robust robot path planning technique is discussed. Concentric Ripple Edge Evaluation and Progression( CREEP ) algorithm[1] has been elaborated and expanded to carry out 3D path planning. Like the 2D case, robot can always find a path, if one exists, in a densely cluttered, unknown and unstructured 3D obstacle environment. 3D space in which the robot is expected to navigate is modeled by stacking cubic cells. The generated path is resolution optimal once the terrain is fully explored by the robot or all the information about the terrain is given. Path planning times are significantly reduced by local path update. Accuracy and efficiency of wave propagation in CREEP algorithm are achieved by virtual concentric sphere wave propagation. Simulations in 2D and 3D spaces are performed and excellent results are demonstrated.

As usual systems, robot manipulators have also physical constraints for operating. It is a difficult problem that we operate manipulator in the minimal time under these constraints. In this pater, we solve this problem dividing it into two steps. In the first step, we find the minimal time trajectories by optimizing qubic polynomial joint trajectories using evolutionary algorithms. In the second step, we optimize controller for robot manipulator to track precisely trajectories optimized in the previous step.

Genetic algorithm(GA) is useful to find optimal solution without any special mathematical modeling. This study presents to search optimal path of Autonomous Mobile Robot(AMR) by using GA without encoding and decoding procedure. Therefore, this paper shows that the proposed algorithm using GA can reduce the computation time to search the optimal path.

In this paper, we develop a control system of an Educational Robot and implement a fuzzy algorithm for the position control. The MA2000 robot manufactured by TecQuipment Co. is the controlled system and 3 axes(waist, shoulder, elbow) of total 6 axes are controlled by the fuzzy logicbased algorithm. The control system consists of an IBM PC, an interface board capable of A/D conversion and PWM generation, and a drive board for dc motors in joints of the robot. The experiments show that the modified fuzzy algorithm yields a better performance in steadystale than that of the conventional fuzzy algorithm.

The Hong Ik Direct Drive Arm(HIDDA) is a SCARA typed direct drive manipulator with two degreesoffreedom(DOF) using the direct drive motor of the NSK company. The direct NSK motors are used to give a large torque directly to the link, to reduce the modeling errors from the gears and chains. But, since the nonlinear coupling torques are transferred to the motor shaft without any reduction, we must consider a dynamic control algorithm. In this paper, we designed a robot controller for the HIDDA using a TMS320C31, which has the highest performance among the third DSP chips in the TI company. And we developed the integrated environment software of the robot management system to give the users an easy way of programming, running and simulation of the robot on the PC.

In this paper, we delelop 4axis motion controller using TMS320c30 DSP chip and build a 5axis vertical articulated robot control system. The 4aixs controller uses a DSP, a highspeed AID and a D/A converter to implement advanced robot control algorithms. The robot control system uses VMEbus and VxWorks realtime multitasking operating system. We use RCCL type to implement robot languages.

A neural network(NN) mechanism is proposed to modify the gait of a biped robot that walks on sloping surface using sensory inputs. The robot starts walking on a surface with no priori knowledge of the inclination of the surface. By accumulating experience during walking, the robot improves its walking gait and finally forms a gait that is adapted to the surface inclination. A neural controller is proposed to control the gait which has 72 reciprocally inhibited and excited neurons. PI control is used for position control, and the neurons are trained by a reinforcement learning mechanism. Experiments of static gait learning and pseudo dynamic learning are performed to show the validity of the proposed reinforcement learning mechanism.

This paper presents an estimation of relative distance and angle from a mobile robot to an object. From the number of pulses required to make the mobile robot move to the feature point, we find the relative distance and angle between the mobile robot and the object. The proposed method shows a practical way of measuring the relative distance and angle between the mobile robot and an object without setting up real world coordinate system.

In this paper, the trajectory needed to be tracked by the manipulator was defined in a new plot differently from conventional methods. And the trajectory provides Solution directly related to coordinates of output variables from the plant. So, it overcomes nonlinearity between joint and Cartesian coordinates in movement mode and it makes use of inverse Kinematics unnecessary, which was obstacle for realtime control. The 2axis SCARA robot was modelled and simulation was performed to validate in this paper. And it proved this has better performance in rapidity and decrease of positionerror, compared to the conventional FLCs.

3D object recognition and restoration independent of the translation and rotation using an ultrasonic sensor array, neural networks and invariant moment are presented. Using invariant moment vectors on the acquired
$16{\times}8$ pixel data, 3D objects can be classified by SOFM(Self Organizing Feature Map) neural networks. Invariant moment vectors kept constant independent of the translation and rotation. The experiment result shows the suggested method can be applied to the environment recognition. 
In a still mill, the effective surface defect inspection algorithm is necessary. For this purpose, this paper proposed the preprocessing algorithm for surface defect inspection of cold mill strip. This consists of live steps. They are edge detection, binarizing, noise deletion, combining of fragmented defect and selecting the largest defect. Especially, binarizing is a critical problem. Bemuse the performance of the preprocessing is largely depend on the binarized image. So, we develope the adaptive thresholding method, which is multilevel thresholding. The thresholding value is varied according to the mean graylevel value of each test image. To investigate the performance of the proposed algorithm, we classified the detected defect using neural network. The test image is 20 defect images captured at German Sick Co. This algorithm is proved to have good property in cold mill strip surface inspection.

In this paper, a small PLC system is designed and developed for the distributed building control and fire control system. It uses 8031, a 8bit micro controller from Intel Inc. The size of the PLC is
$7cm{\times}8cm$ and the PLC can accept 4 sensor inputs and drive 4 relay outputs, which operates at 24V. Multiple access of PLC by one host computer is implemented by assigning a unique 10 to each PLC, which ranges from 0 to 126. The operation starts by sending a command packet from host computer to a PLC and the PLC of the same 10 fetches the command packet by comparing the first byte of the command packet with its own 10. The PLC is programmed to perform a various functions and the function is selected by the content of the command byte, which is the second byte of the command packet. The third byte, which is the last byte, is a checksum byte. The checksum byte is the sum of the first byte and the second byte and is used to detect the communication error. Depending on the content of the command byte, PLC performs the desired function and returns the response packet back to the host computer. The response packet is also a threebyte packet, 10 byte, response byte and checksum byte. For the independent operation of PLC without being controlled by the host computer, variable length RULE data packet is sent to PLC. In case the communication line is broken, the PLC perform the independent operation by referencing the RULE data. The applicable areas are; building automation system, distributed factory automation, measurement of temperature of toxic or dangerous area. 
The objective of camera calibration is to obtain the correlation between camera image coordinate and 3D real world coordinate. Most calibration methods are based on the camera model which consists of physical parameters of the camera like position, orientation, focal length, etc and in this case camera calibration means the process of computing those parameters. In this research, we suggest a new approach which must be very efficient because the artificial neural network(ANN) model implicitly contains all the physical parameters, some of which are very difficult to be estimated by the existing calibration methods. Implicit camera calibration which means the process of calibrating a camera without explicitly computing its physical parameters can be used for both 3D measurement and generation of image coordinates. As training each calibration points having different height, we can find the perspective projection point. The point can be used for reconstruction 3D real world coordinate having arbitrary height and image coordinate of arbitrary 3D real world coordinate. Experimental comparison of our method with wellknown Tsai's 2 stage method is made to verify the effectiveness of the proposed method.

The vision processing system for mobile robots requires real time processing and reliability for the purpose of safe navigation. But, general types of vision systems are not appropriate owing to the correspondence problem which correlates the points out of two images. To determine the obstacle area, we use correspondences of line segments between two perspective images sequentially acquired by camera. To simplify the correspondence, the matching of line segments are performed in the navigation space, based on the assumption that mobile robot should be navigated in the flat surface and the motion of mobile robot between two frames should be approximately known.

Kim, MoonCheol;Kim, EungSeok;Huh, WooJung;Shin, KyeongBong;Cho, YoungJo;Ryu, HaeYoung 1254
Design methods for sequence flow controllers play an important role in industrial automation. To design a flexible, reusable, and maintainable control software has become a key issue nowadays. Petri net has been emerging as an important tool to provide an integrated solution for modeling, analysis, simulation, and control of industrial automated systems recently. This paper describes an international standard of programming languages for programmable logic controllers, IEC 11313 SFC( Sequential Function Chart), and the sequence flow control method for an SFC using a Petri netlike model. 
Kim, EungSeok;Kim, MoonCheol;Huh, WooJung;Shin, KyungBong;Park, JungMin;You, BumJae;Cho, YoungJo;Kim, KwangBae;Ryu, HaeYoung;Ahn, ByungGyu 1257
In this paper, we introduce an integrated communication and control system(ICCS) for control of a crane. The system is integrated with a compasite technique as a network interfacing, a user interfacing and a system control for continuous process like as a container crane. The fieldbus(Profibus) network module is used to interconnect each input/output module with main control unit. The MMI system for user interfacing is integrated with an ODBCbased data management tool and IECl131based control logic design tool(SoftLogic Designer:SLD). The each programmed control task in the main Controller is executed using a petrinet based scheduler. 
Shin, KyeongBong;Huh, WooJung;Kim, MoonCheol;Kim, EungSeok;Kim, WangKil;Hwang, JinSik 1260
There has been much interested on the issues of designing and implementing the data acquisition and display system. This paper describes how to acquire and manage the data to be generated from sensor sources in a manufacturing process. The functionality of this data management system is composed of data acquisition, database management, processing and display of the available data. Also, this system has a adaptability to be carried throughout configuration management. 
Huh, WooJung;Shin, KyeongBong;Kim, EungSeok;Kim, MoonCheol;Park, JungMin;Kim, SungTae 1263
IEC11313 Specification of Programming Controller is established in 1994 and consists of 3 graphical languages and 2 textual languages. It is used in PLC and small scale controller because of its uniformity and extensibility. This paper describes Soft Logic Designer which is a graphical and textual programming editor for IEC11313 programming languages. Soft Logic Designer is developed with Object Orient Language, C++ under Microsoft Windows 95. It has two graphic editors for Sequential Function Chart and Function Block Diagram and one textual editor for Structured Text. Users can efficiently write highlevel programs with mouse and menu buttons. 
In this study an automatic roilingcoli labeling system using robot vision system and peripheral mechanism is proposed and implemented, which instead of the manual labor to attach labels Rollingcoils in a steel miil. The binary image process for the image processing is performed with the threshold, and the contour line is converted to the binary gradient which detects the discontinuous variation of brightness of rollingcoils. The moment invariants algorithm proposed by Hu is used to make it easy to recognize even when the position of the center are different from the trained data. The position error compensation algorithm of six degrees of freedom industrial robot manipulator is also developed and the data of the position of the center rollingcoils, which is obtained by floor mount camera, are transfered by asynchronous communication method. Therefore even if the position of center is changed, robot moves to the position of center and performs the labeling work successfully. Therefore, this system can be improved the safety and efficiency.

This paper presents a visual servoing combined by evolutionary algorithms and neural network for a robotic manipulators to control position and orientation of the endeffector. Using the multi layer feedforward neural network that permits the connection of other layers, evolutionary programming(EP) that search the structure and weight of the neural network, and evolution strategies(ES) which training the weight of neuron, we optimized the net structure of control scheme. Using the four feature image information from CCD camera attached to endeffector of RVM2 robot manipulator having 5 dof, we generate the control input to agree the target image, to realize the visual servoing. The validity and effectiveness of the proposed control scheme will be verified by computer simulations.

This paper presents the development of tactile sensor systems for robot hand which are truly usable, robust, reliable and cheap system. The sensor incorporates multiple sensing subsystems for detecting distributed contact forces and surface characteristics. The fabrication and experimental evaluation of the tactile system and its electric interfaces are described. The results indicate that the system provides reasonable performances for practical applications requiring manipulation with tactile feedback.

The Sequence Of Event (SOE) system used in nuclear power plants is a part of the Plant Data Acquisition System (PDAS). The SOE system of the existing nuclear power plant share the computer H/W and S/W, and required more complicated structure to provide the events or trip signals. Moreover, there are high potential of collision between synchronization signals and data transmitted to the Plant Computer System(PCS) when the synchronization signals are sent from PCS to the three SOE processors. When this collision happens the SOE system will break down, thus it is not possible to analyze the trend of events or trips. This paper issued the limitation items of the existing SOE system and proposed the revised SOE system.

In this paper, an Iterative learning control algorithm is presented for a class of non linear system which have external inputs or disturbances. The acceleration of error signal is used to update the next control signal. It is shown that the feedback gain can be deter.ined so that the overall errors are convergent.

This paper proposed frequency estimation the method of distorted sinusoidal signals by harmoics. An approximate estimation based on FFT and the accurate basic frequency was estimated by proposed method with Fourer Series, and the harmonics were estimated by the basic frequency. The sinusoidal signals is extracted by filter banks based on the estimated hamonics. The rate of basic and hamonics power is estimated by the extracted sinusoidal signals and we developed their algorithm and programs.

An add/drop control chip for SDH transmission system has been designed in AT&T 0.5um CMOS ORCA FPGA. This device plays an important role in achieving selfhealing ring operation which protects against failure. After this device receives each 24ch AU3 signals from the west, east, and add parts, it outputs each 24ch switched signals through the control data of system control port. This device consists of eight subpart such west/east transmitting part, west/east receiving part, add/drop control part, AIS control part, and CPU interface part. The designed device is capable to ring networks as well as linear networks.

In this paper, we propose a new adaptive preprocessing technique for the linearization of a weakly nonlinear system which can be modeled by a Volterra series up to third order. To compensate the nonlinear effects of a given system, an update algorithm for the linear filter coefficients of the proposed adaptive preprocessor is introduced, and to compensate the linear distortion of the given system, the linear inverse filter is also utilized. For the performance test of the proposed adaptive preprocessor, computer simulation results obtained by analyzing an ANRSS loudspeaker model are provided.

The general output circuit for PWM output is pushpull using a complimentary MOSFET. The gate driver coupled directly at gate can switch easy upto a high frequency. However, a high reverse recovery current and parastic components make a oscillation output. This paper analyses this phenomenon and proposes a novel output circuit preventing the oscillation.

CCITT G.721, G.723 standard ADPCM algorithm is implemented by using TI's fixed point DSP start kit (DSK). ADPCM can be implemented on a various rates, such as 16K, 24K, 32K and 40K. The ADPCM is sample based compression technique and its complexity is not so high as the other speech compression techniques such as CELP, VSELP and GSM, etc. ADPCM is widely applicable to most of the low cost speech compression application and they are tapeless answering machine, simultaneous voice and fax modem, digital phone, etc. TMS320C50 DSP is a low cost fixed point DSP chip and C50 DSK system has an AIC (analog interface chip) which operates as a single chip A/D and D/A converter with 14 bit resolution, C50 DSP chip with onchip memory of 10K and RS232C interface module. ADPCM C code is compiled by TI C50 Ccompiler and implemented on the DSK onchip memory. Speech signal input is converted into 14 bit linear PCM data and encoded into ADPCM data and the data is sent to PC through RS232C. The ADPCM data on PC is received by the DSK through RS232C and then decoded to generate the 14 bit linear PCM data and converted into the speech signal. The DSK system has audio in/out jack and we can input and out the speech signal.

The application field of photovoltaic system which has nopollution and nofuel distinctives is being spreaded inspite of its high installation cost. At present, there are three PV systems within the country, which were already installed and have been operated to supply the electric power in remote island. In this paper, the electrification plan of our government on the unelectrified or subelectrified islands is introduced, and the operation results of three PV systems are investigated to discuss the diffusion possibility of PV system as a power supply option.

A new automatic frequency control(AFC) tracking algorithm, which we call a rotational decision directed AFC(RDDAFC) is proposed for QPSK demodulation at the digital direct broadcasting satellite(DBS). In order to prevent the presence of the residual phase difference between symbols received at k and kl by the CPAFC[1] as well as the AFC based on
$tan^{1}$ circuit[2], the RDDAFC rotates the decision boundary for the kth received symbol by the frequency detector output of the (k1)th received symbol before passing through the cross product discriminator. Test results show that the total pullin time of the RDDAFC and PLL was 0.13msec under a carrier frequency offset of 2.4MHz when S/N equals 2dB. 
Signal Amplifying Gate Driver of SelfExcited Electronic Ballast for High Pressure Sodium (HPS) LampA regenerative signal amplifying gate driver of selfexcited electronic ballast is presented. It can be used for high pressure sodium (HPS) lamp without auxiliary external ignitor. Since the HPS lamp requires very high ignition voltage at start up, the resonant frequency of the circuit must be increased to obtain high voltage oscillations in spite of relatively small resonant current. The presented gate driver amplifies the current of gate drive transformer and raises the gatesource voltage Quickly to turn on the MOSFET switches. Hence, the resonant frequency can be increased more than 100kHz. The HPS lamp used in the simulation and experiment has the rating of 400W input power at 220V input ac voltage source. The experiments show that the resonant frequency is above 150kHz at start up.

This paper presents hybrid active noise control (HANC) systems which is based on the combination of feedforward and feedback ANC controllers. HANC systems use FIR filters and is based on primary noise regeneration principle and filteredX LMS algorithms. HANC systems show better attenuation characteristics and residual spectrum. The order of adaptive filters used in HANC systems is lower than that of conventional feedforward and feedback ANC systems. A proposed HANC algorithm was implemented using a Taxas Instruments TMS320C31 digital signal processor for experimental verification.

In this study, the algorithm for detection of evoked potentials is proposed. The observed evoked potentials are first preprocessed by blind identification so as to eliminate the ongoing EEG Bile noise. Then, statistic characteristics of the peak components i.e latency and amplitude are detected from prefiltered responses by latencycorrected averaging method. The performance of blind identification is compared with those of adaptive fillers as to deterministic and stochastic EPs, is assessed in terms of NMSE, distortion index, correlation coefficient with original EPs. The estimated deterministic and stochastic EPs restored with peak components are compared and assessed. The results show the superiority of this proposed algorithm using blind identification in detecting deterministic and stochastic EPs.

This paper presents a new method to obtain more stable and precise A/D conversion for remote sensing use. Hardware is designed to compensate offset voltage and drift & temperature characteristics, as well as to perform dual slop A/D converter by using single chip microprocessor. Serial communication program which is based on ASCII code commands is also developed to add initial setup & calibration functions as well as to perform A/D data communication. Proposed method will give a good applications to the industrial field where a high precision remote sensing is required.

진폭변조(AM) 신호를 검파기하기 위한 디지탈 시스템을 실현하기 위해서는 보통 변조된 신호의 최대주파수의 2배 이상되는 주파수로 샘플링해야만 한다. 이러한 경우에 반송파가 커지면 처리할 데이터가 많아지기 때문에 디지탈 시스템이 복잡해져 실시간 처리가 어렵게 된다. 본 연구에서는 샘플링 주파수를 대역폭을 기준으로 하여 낮출 수 있는 유용한 두 종류의 복조시스템을 제안하였다. 또한 undersampling한 복조회로에 대한 특성 및 오차를 해석하고 검토하였다.

기존의 창함수를 이용한 1차원 FIR 필터의 설계는 설계방법이 단순해 비교적 많이 사용되고 있으나 통과영역과 천이영역을 가변할 수 없다. 본 연구에서는 두 개의 영역을 가변할 수 있는 창함수를 사용하여 1차원 임펄스 응답을 구한 후 McCllenan 변환 방법을 이용하여 2차원 FIR 필터를 실현하여 특성을 비교하여 2차원 FIR 필터의 설계에 적용할 수 있음을 밝혔다.

This paper describes an air conditioner control method using a fuzzy control theory. The fuzzy control method was implemented with Philips 80C552 one chip microcomputer and tested in an actual vehicle. Experiments showed that proposed control method is superior to the conventional PID control method especially in the environments with abrupt disturbance and parameter variation of the control system. FuzzyBased control method was proved to maintain a stable and improved temperature control in an abrupt environmental changes.

This paper presents an active noise control (ANC) algorithm using orthogonalization property of Walsh transform. Conventional ANC algorithm known as filteredx LMS(FXL) algorithm has a problem of decreasing convergence speed in FIR adaptive filters operating in colored noise environments. Walsh transform decompose an input signal into a set of N uncorrelated components and reduce eigenvalue spread of autocorrelation matrix of input sequences. Computer simulations show that proposed (FXW) algorithm is superier to FXL in convergence speed.

Power telecommunication networks is being increased rapidly in that expansion of power plant according to the growth of electric power supply. The requirement of power plant operation & office automation make it to complex and confusing to operate. So, for the sake of correspond to the change, it is necessary that telecommunication network should be high reliable and managed effectively. In this paper, we suggest total reliability evaluation models for power telecommunication network which is based on the QOS(quality of service) standardization techniques recommanded by ITUT.

Otoacoustic emissions(OAEs) are lowlevel sounds produced by the inner ear. This is based on the discovery that the cochlea in the normal human inner ear itself emits in the form of acoustic energy. Thus we transmit the stimulus to the ear through speaker then measure the evoked response using miniature microphone. Otoacoustic emissions are averaged by timelocking so that distinguish the spectrum between normal human and impaired.

A new model of dynamic hysteresis loops is presented. The model is a TSK fuzzy model and can be identified by using inputoutput data obtained from hysteresis loop systems. The model is shown to exhibit an increase in area of the loop with frequency, which is a hysteretic property.

This paper presents a design method for an online adaptive neural networks based intelligent controller. The proposed neural controller, assuming PID controller is initially presented, learns the equivalent behaviors of the existing PID controller initially and switches to take over the PID control system. Then, it executes online adaptation via evaluating its performance and minimizing user defined cost function constantly so that the optimal control can be achieved. The PID controller and the proposed neural controller are investigated and compared in computer simulation.

In this paper, we discuss an informal analysis of diffusion, global optimization properties of Langevine competitive learning neural network. In the view of the stochastic process, it is important that competitive learning gurantee an optimal solution for pattern recognition. We show that the binary reinforcement function in Langevine competitive learning is a brownian motion as Gaussian process, and construct the FokkerPlank equation for the proposed neural network. Finally, we show that the informal analysis of the proposed algorithm has a possiblity of globally optimal. solution with the proper initial condition.

Most real image sequences contain multiple moving objects or multiple motions. In this paper, we segmented the moving objects with optical flow. Motion estimation by this method can estimate and compress the image sequences better than other methods such as block matching method. And, especially, we can make new image sequences by synthesizing the segmented objects. But, it takes too much time for motion estimation. And, it is not easy for a hardware implementation.

The purpose of image sequence coding is to reduce the spatiotemporal redundancies. For the spatial redundancies, we can use the transform coding such as DCT. In this paper, the optical flow method is applied to solve the problem of temporal redundancies. There are several estimation methods like block matching method and pelrecursive method. Block matching method is easy for a hardware implementation because of the computational simplicity. So, it is now used as the estimation method in MPEGl, MPEG2, and H.261. We compared the merits and demerits of the optical flow method and the block matching method in this paper.

This paper presents classification of high impedance fault pattern using linear prediction coefficients. A feature of neutral phase current is extracted by the linear predictive coding. This feature is classified into faults by a multilayer perceptron neural network. Neural network successfully classifies test data into three faults and one normal state.

Hopfield's suggestion of a neural network model for associative memory aroused the interest of many scientists and led to efforts of mathematical analyses. But the Hopfield Network has several disadvantages such as spurious states and capacity limitation. In that sense many scientists and engineers are trying to use a new optimization algorithm called genetic algorithm. But it is hard to use this algorithm in Hopfileld Network because of the fixed architecture. In this paper we introduce another method to determine the weight of Hopfield type network using Genetic Algorithm.

This paper describes a design of real time fuzzy controller using Minimum fuzzy control Rule Selection Method(MRSM). The control algorithm of dynamic systems needs less computation time and memory. To reduce the computation time of fuzzy logic controller, minimum number of rules are to be selected for the fuzzy input variable. The universe of discourse is divided by the number of linguistic labels to allocate the assigned membership function to the fuzzy input variables. In this case, since fuzzy input variables are continuous, scale factor SU is tuned independently. According to increment of SU control surface is improved to adapt the change of system parameter. At this, crisp control surface is increased. With the increament of crisp control surface, fuzzy control surface is reduced. When error state deviates from desirable error state, crisp control surface is more useful than fuzzy control surface for obtaining fast rising time.

In this paper a Dear lossless compression of medical images with vector quantizer is proposed. In order to apply the vector quantizer to medical images, the peak error in the reconstructed image is reduced down to 1. Simulation results show that the proposed coding scheme provides better performance with a PSNR improvement compared to the conventional JPEG standard.

본 연구에서는 확정진단시의 무릎 CT 화상을 대상으로해서 화상인식의 제1단계로써, 최근 여러분야에서 많은연구가 행해지고 있는 3층역전파신경회로망(BPN)에 의한 무릅덮개뼈 탈구중의 자동진단 가능성에 관해서 검토를 행했다. 실험결과로부터 신경회로망에 의한 무릅덥개뼈 탈구화상의자동진단은 충분하다고 할 수는 없어도 가능성이 있음올 알게 되었다. 다만, 본 실험에서사용된 패턴수가 적어, 충분한 학습이 이루어지지 않았을 가능성이 있으며, 또한 test된 화상수도 충분치 못하였다. 데이터의 증가에 수반해서 인식률이 충분히 한 향상될 것으로사료된다. 신경회로망은 원리척으로 패턴변환의 한 종류로써, 현상태의 기술수준을 고려할때 과도의 기대는 금물이지만, 패턴인식, 화상처리 등 종래의 계산기가 능숙하게 대처하지 못했던 분야에 대해서 큰 기대를 부여하고 있다. 특히 의공학연구에 있어서 BPN의 응용범위를 사고한다면, 확정진단시에 있어 의사가 보다 확실한 진단을 할 수 있도록 진단지원에 휴익한 도움을 줄 수 있을 것으로 사료된다.

The Information of Edges which takes small area comparing with the total image is very important in DNA images as well as general images. DNA image is the object should be managed by computing and it's demanding information is less than general images, but the accuracy is more important In a huge DNA image processing system such as DNA Information Bank, the performance depends on the size of image. In this paper, we extract the edge information and make it as a binary image. To reduce the size of the original image, it was applied by JPEG image compression method. The compressed image is combined with edge information when they are restored. As a result, Both the image compression ratio and restoration quality are optimized without the loss of critical information.

A clustering algorithms with dynamic adjustment of learning rate for GBFCM(Gradient Based FCM) is proposed in this paper. This algorithm combines two idea of dynamic Kmeans algorithms and GBFCM : learning rate variation with entropy concept and continuous membership grade. To evaluate dynamic GBFCM, we made comparisons with Kohonen's SelfOrganizing Map over several tutorial examples and image compression. The results show that DGBFCM(Dynamic GBFCM) gives superior performance over Kohonen's algorithm in terms of signaltonoise.

In this paper We proposed a new method to generate fuzzy logic controllers through genetic algorithm(GA). In designing of fuzzy logic controllers encounters difficulties in the selection of optimized membership functions, gains and rule base, which is conventionally achieved by a tedious trialanderror process. This paper develops genetic algorithms for automatic design of high performance fuzzy logic controllers which can overcome nonlinearities in many engineering control applications. The rulebase is coded in base7 strings by generated from random function. Which can be presented in discrete fuzzy linguistic value, and using membership function with Gaussian curve. To verify the validity of this fuzzy logic controller it is compared with conventional fuzzy logic controller(FLC) and PID controller.

In this paper, each parameter was identified by the gradient descent method to overcome difficulty deciding fuzzy rules of FLC for the unknown process and the type of membership Junctions. Usually PID or optimal control theories have been mostly usee in control field so far. However, optimal control requires much time for calculation because of adaptation for disturbance and nonlinearity. And intricate technique such as MRAS which can be realized only by an expert are limited to be used in the systems requiring rapid and precise response because of comparatively longer calculating time and complicateness. Gradient descent method is a method to find Z minimizing a function about a certain vector Z. And required output of FLC is gained using gradient approaching method in order to adapt control rule parameters of FLC. Simulation proved validation of this algorithm.

In this paper, a motion estimation module is made with ADSP21020 based on MPEG2 which is an international standard for moving picture compression. And, the block matching algorithm used as motion estimation method is easy for an hardware implementation. The ADSP21020 of Analog Device is used for a main control processor. We used three block matching method (exhaustive search method, 2Dlogarithmic search method, three step search method) for software simulation and implemented the three step search method to hardware. For the test of the estimation module, we used ping pong image sequences and mobile and calendar image sequences.

Network환경에서 World Wide Web을 이용하여, 원격 제어 핵자기 공명 영상 시스템을 구성하였다. 시스템 구성은 핵자기 공명 영상 시스템의 host computer에 HTTP server를 구축하였으며 원활한 원격 실험을 위하여 화상 및 음성통신 기능도 추가하였다. 개발된 시스템으로 광운대학교의 신호처리연구실에서 대전 KAIST의 의학 영상 공학 센터에 있는 원격 핵자기 공명 영상 시스템을 조정하여 실험을 수행할 수 있었다.

In this paper, a recurrent neural network using polynomial is proposed for electric load forecasting. Since the proposed algorithm is based on the bilinear polynomial, it can model nonlinear systems with much more parsimony than the higher order neural networks based on the Volterra series. The proposed Bilinear Recurrent Neural Network(BLRNN) is compared with Multilayer Perceptron Type Neural Network(MLPNN) for electric load forecasting problems. The results show that the BLRNN is robust and outperforms the MLPNN in terms of forecasting accuracy.

In this paper, we applies two methods  Genetic Algorithm(GA) and
$A^*$ Algorithm  to find the optimal path in route guidance system. Under the assumption that the traveling costs of each link are given, the task to find the optimal path becomes very complicated problem if the number of nodes or links increase. Two wellknown algorithms are modified to resolve the problem and the preliminary demonstration show both optimistic result and needs to improvement. 
This paper presents an algorithm to separate vowels from consonants in Korean characters captured in noisy images and to recognize them. The algorithm has been originally developed for the recognition of the usage code (which is represented by a single Korean character) in the license plates or Korean vehicles. It, however, could be easily adopted to other applications with minor changes, in which character recognition is needed and the environment is noisy. The key ideas or the algorithm are to localize the vowels utilizing the Hough transformation and to separate the vowels from consonants utilizing mathematical morphology. We observed that the presented algorithm effectively separates vowels even if the vowels and consonants are joined together after thresholding. We also observed that our algorithm outperforms some conventional algorithms especially when the input images are noisy. The details of the comparison study are presented in the paper.

Many of the existing neural associative memories are trained and recalled in separate modes and are not suitable for temporal pattern storage and classification in that user must specify the time and length of input patterns. In this paper, a new online temporal associative memory model is presented. This memory is structured in layers of neurons and each neuron has limited number of weights so that calculation complexity can be considerably reduced and processing of patterns can be achieved in real time.

In this paper, a method of the decision of the road direction for ALV(Autonomous Land Vehicle) road following by regionbased segmentation is presented. The decision of the road direction requires extracting road regions from images in realtime to guide the navigation of ALV on the roadway. Two thresholds to discriminate between road and nonroad region in the image are easily decided, using knowledge of problem region and polygonal approximation that searches multiple peaks and valleys in histogram of a road image. The most likely road region of the binary image is selected from original image by these steps. The location of a vanishing point to indicate the direction of the road can be obtained applying it to XY profile of the binary road region again. It can successfully steer a ALV along a road reliably, even in the presence of fluctuation of illumination condition, bad road surface condition such as hidden boundaries, shadows, road patches, dirt and water stains, and unusual road condition. Pyramid structure also saves time in processing road images and a realtime image processing for achieving navigation of ALV is implemented. The efficacy of this approach is demonstrated using several realworld road images.

A new method is proposed for tracking the optimum points in nonstationary problem via genetic search. Cache Pool to save the past genetic informations is added to population in search using Sexual Reproduction Genetic Algorithm(SRGA). In Cache Pool, elite chromosomes from population are accumulated. A best Individual is made up from these chromosomes in varying environment and inserted into the newly reproduced population every generation. Experimental results indicate changing global optima are accurately identified and followed.