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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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The Journal of Advanced Navigation Technology
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Journal DOI :
The Korea Navigation Institute
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Volume & Issues
Volume 16, Issue 6 - Dec 2012
Volume 16, Issue 5 - Oct 2012
Volume 16, Issue 4 - Aug 2012
Volume 16, Issue 3 - Jun 2012
Volume 16, Issue 2 - Apr 2012
Volume 16, Issue 1 - Feb 2012
Selecting the target year
Simple and Efficient Design Method of Stepped Septum Polarizer for X-band Satellite Communication
Kim, Jee-Heung ; Lee, Jae-Wook ; Lee, Taek-Kyung ; Cho, Choon-Sik ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 893~899
DOI : 10.12673/jkoni.2012.16.6.893
In this paper, a simple design method of stepped septum polarizer suitable for X-band satellite communication is proposed. This method is compared to two other conventional design methods in terms of time consumption and complexity of design procedure. In addition, an equivalent circuit modeling is used to analyze and design for the polarizer based on waveguide. For the validity of satisfying the satellite communication, electrical performances have been verified through the simulation and measurement results.
Precision Orbit Propagator for Low Earth Orbiters
Kim, Jeong-Rae ; Noh, Jeong-Ho ; Kee, Chang-Don ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 900~909
DOI : 10.12673/jkoni.2012.16.6.900
Low Earth orbit satellites with satellite navigation receiver use onboard navigation filters for filtering measurement signals and for orbit prediction under signal loss. Precision satellite dynamic models, core of the navigation filter, are studied and a computation program is developed. Gravity acceleration, precision coordinate transform, third-body gravity, atmospheric drag, and solar radiation pressure models are combined into an orbit prediction algorithm, and a proven precision orbit determination software is used to validate the program. Orbit prediction accuracy is analyzed with simulated and flight orbit data. The program meets an accuracy level for onboard real-time navigation filter.
Fixed-Wing UAV`s Image-Based Target Detection and Tracking using Embedded Processor
Kim, Jeong-Ho ; Jeong, Jae-Won ; Han, Dong-In ; Heo, Jin-Woo ; Cho, Kyeom-Rae ; Lee, Dae-Woo ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 910~919
DOI : 10.12673/jkoni.2012.16.6.910
In this paper, we described development of on-board image processing system and its process and verified its performance through flight experiment. The image processing board has single ARM(Advanced Risk Machine) processor. We performed Embedded Linux Porting. Algorithm to be applied for object tracking is color-based image processing algorithm, it can be designed to track the object that has specific color on ground in real-time. To verify performance of the on-board image processing system, we performed flight test using the PNUAV, UAV developed by LAB. Also, we performed optimization of the image processing algorithm and kernel to improve real-time performance. Finally we confirmed that proposed system can track the blue-color object within four pixels error range consistently in the experiment.
A proposal to build comprehensive maritime safety communication networks
Yang, Gyu-Sik ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 920~926
DOI : 10.12673/jkoni.2012.16.6.920
In this paper, marine accidents recently happened in Korea and Japan for 5 years, especially through the analysis of accident characteristics for fishing vessels, including small vessels were analyzed. Also propose a new maritime safety communication network in the form of a comprehensive considering the wave propagation characteristics and operational characteristics of radio communication equipments should be installed in the vessel through comprehensive analysis of the regulation according to the radio equipment and the ship`s location identification device installation and operation.
Improvement of Relative Positioning Accuracy by Searching GPS Common Satellite between the Vehicles
Han, Young-Min ; Lee, Sung-Yong ; Kim, Youn-Sil ; Song, June-Sol ; No, Hee-Kwon ; Kee, Chang-Don ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 927~934
DOI : 10.12673/jkoni.2012.16.6.927
In this paper, we present relative positioning algorithm for moving land vehicle using GPS, MEMS IMU and B-CDMA module. This algorithm does not calculate precise absolute position but calculates relative position directly, so additional infrastructure and I2V communication device are not required. Proposed algorithm has several steps. Firstly, unbiased relative position is calculated using pseudorange difference between two vehicles. Simultaneously, the algorithm estimates position of each vehicle using GPS/INS integration. Secondly, proposed algorithm performs filtering and finally estimates relative position and relative velocity. Using proposed algorithm, we can obtain more precise relative position for moving land vehicles with short time interval as IMU sensor has. The simulation is performed to evaluate this algorithm and the several field tests are performed with real time program and miniature vehicles for verifying performance of proposed algorithm.
Site Selection Method of Receiving Stations for the GNSS Based Transportation Infrastructure Network Analyzing the Environment of Site Candidates
Son, Min-Hyuk ; Kim, Geo-Heon ; Lee, Eun-Sung ; Heo, Moon-Beom ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 935~943
DOI : 10.12673/jkoni.2012.16.6.935
In this paper a three step procedure was derived to select the GNSS network receiving site candidates for GNSS based infrastructure technology development and according to the proposed procedure the 4 site candidates was selected for final network configuration. In the first step, the site requirement was produced for GNSS based infrastructure technology development referring regulation of the international organizations related to permanent GNSS data receiving and the first candidates were selected using the proposed requirement. In the second step, the second candidates were selected among the first candidates by analyzing the visual measurement, environment test and so on. In the third step the final candidates were selected among the second candidates by analyzing sky clearance, radio frequency interference. Through above the three step procedure 16,7,4 candidates of site were selected sequentially and receiving station site could be effectively selected.
Analysis of Sky-View-Factor based Dilution of Precision for Evaluation of GNSS Performance in Land Road Environment
Hong, Woon-Ki ; Choi, Kwang-Sik ; Lee, Eun-Sung ; Im, Sung-Hyuck ; Heo, Moon-Beom ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 944~951
DOI : 10.12673/jkoni.2012.16.6.944
The conventional indexes for describing the GNSS positioning performance such as satellite visibility, dilution of precision (DOP) and signal to noise ratio is very useful in open sky, however, they are not useful in the land road environment. In this paper new index is suggested for describing the GNSS positioning performance for the road environment. The new index is called Sky View based DOP (SVDOP). SVDOP is derived referring the Sky-View-Factor (SVF). The usefulness is analyzed by comparing the SVDOP and SVF in land road environment after the singularity points are selected and SVDOP is calculated.
ESPRIT target position estimation with uniform linear array and uniform circular array
NamGoong, Geol ; Lim, Jong-Tae ; Yoo, Do-Sik ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 952~959
DOI : 10.12673/jkoni.2012.16.6.952
In this paper, we propose an ESPRIT based algorithm for target position estimation with uniform linear array (ULA) and uniform circular array (UCA) at transmitter and receiver, respectively. When UCA is adopted at the receiver, unlike the case of ULA at the receiver, the rotational invariance of the received signal is satisfied. Although there has been an attempt to resolve this issue, the problem of direction of departure estimation has not been considered. In this paper, we provide an ESPRIT based algorithm to simultaneously estimate transmitter elevation angle, receiver elevation angle, and receiver azimuth angle, taking into account the transmitter antennas as well as the receiver antennas.
LQI Standard Deviation Routing Algorithm for Energy Loss Reduction in Wireless Sensor Networks
Shin, Hyun-Jun ; Oh, Chang-Heon ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 960~967
DOI : 10.12673/jkoni.2012.16.6.960
Wireless sensor network is used at the environment to obtain nearby information and since such information is transferred through wireless link, it causes unnecessary re-sending and disadvantage of big energy consumption at node. Because of this to select reliable, energy effective link, method of estimating quality on wireless link using RSSI(received signal strength indication), LQI(link quality indication), etc is needed on wireless link. To set up path extending survival time by reducing energy consumption of nodes at the wireless sensor network, the thesis selects with small standard deviation of LQI after obtaining LQI within each path. Additionally, LQI standard deviation routing algorithm is compared based on LQI algorithm such as minimum-LQI, hop-LQI weight and RF output -7dBm. According to the outcome, the algorithm suggested has superior characters such as the number of node, retransmission rate and network life span respectively compared to existing algorithm. Therefore, energy consumption can be efficiently reduced in case that LQI standard deviation routing scheme suggested by this paper is adapted to wireless sensor network.
Web based File Transmission System using HTML5
Kim, Yu-Doo ; Kim, Mo-Han ; Moon, Il-Young ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 968~974
DOI : 10.12673/jkoni.2012.16.6.968
After launched various smart devices such as smart phone and tablet PC, people who using smart devices are provided various services. Especially, contents sharing technology is utilized in any devices. But current contents sharing systems are made on various versions for various smart devices. These methods will be raising cost for development of application. Therefore it must using web technology for reducing cost. In this paper, we had analyzed performance of file transmission using web technology and compared with application based system.
A Study on the SNR Estimation Performance of Hierarchical 16QAM
Kwak, Jae-Min ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 975~981
DOI : 10.12673/jkoni.2012.16.6.975
The SNR estimation performance of hierarchical 16QAM system, which is adopted to simultaneous transmission or efficient image transmission system, is analyzed. Hierarchical 16QAM is modulation system which has different constellation shape from conventional QAM and can provide users with high quality and low quality of data services simultaneously by controlling hierarchical modulation parameter. Assuming AWGN channel, SNR estimation performance characteristics are investigated considering hierarchical modulation parameter and type of constellation points. From simulation results, it is found that constellation point showing superior SNR estimation performance relative to other points is exist. Also, it is known that according to hierarchical modulation parameter, SNR estimation range with more accurate estimation performance is divided.
Performance Enhancement of Decision Directed SNR Estimation by Correction Scheme of SNR Estimation Error
Kwak, Jae-Min ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 982~987
DOI : 10.12673/jkoni.2012.16.6.982
In this paper, the SNR estimation error of Decision Directed SNR estimation method in AWGN is investigated, which uses samples received in reference decision region. In communication system receiver, when SNR estimation scheme using error vectors between ideal sample points and received sample points of reference region is adopted, the samples contain incorrectly received samples due to AWGN. Consequently, the mean of estimated reference constellation point is shifted and Decision Directed SNR estimation is inaccurately performed. These effects are explained by modified probability density function and difference between actual SNR and estimated SNR is theoretically derived and quantatively analyzed. It is proved that SNR estimation error obtained through computer simulation is matched up with derived one, and SNR estimation performance is enhanced significantly by adopting suggested correction scheme.
Efficient Interference Alignment for Uplink MIMO/FDD Systems with Limited Feedback
Cho, Sung-Yoon ; Jang, Jin-Young ; Kim, Dong-Ku ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 988~996
DOI : 10.12673/jkoni.2012.16.6.988
Assuming perfect channel state information (CSI), the conventional interference alignment (IA) algorithm in the uplink cellular system suppresses inter-cell interference (ICI) by aligning ICI to a randomly selected reference vector. However, IA in practice relies on limited feedback between base stations and users, resulting in residual ICI. In this paper, we propose the optimization of the reference vector that minimizes the upper-bound of residual ICI power. Secondly, the iterative IA that designs the direction of transmit and receive filter is proposed to minimize the residual ICI as well as maximize the desired signals. Moreover, we propose the user scheduling method combined with proposed IA schemes which provides the multiuser diversity gain in multi-cell environments. Finally, the performance gain of the proposed IA algorithms compared with the existing IA are analyzed and demonstrated by simulation results.
A Signal Quality Measurement Algorithm for CDMA2000 1x Reverse-link
Kang, Sung-Jin ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 997~1004
DOI : 10.12673/jkoni.2012.16.6.997
In this paper, we propose and implement a signal quality measurement algorithm for CDMA2000 1x terminal. The proposed algorithm is suitable to be implemented in software on a PC-based platform and extract the received signal after carrying out equalization, PN code acquisition and tracking, frequency and phase offset compensation with 4-oversampled input signal. Then, through despreading and demodulation with the extracted signal, the proposed algorithm regenerate the reference signal to be used in measurement. The signal quality is measured using this regenerated signal and the extracted signal.
A Study on the Effect of the Motor Drive in Simulation Analysis by Induction Motor Parameters Using a Matlab & PSPICE
Na, Seung-Kwon ; Ku, Gi-Jun ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1005~1013
DOI : 10.12673/jkoni.2012.16.6.1005
In this paper, the induction motor in indirect vector control method modeling, from indirect vector control method it undergoes an influence to the
. When changing a rotor resistance because being like this quality Matlab/Simulink where it will make what kind of effect in speed presumption it led proposed control system used microprosser TMS320C31 DSP for high speed processing. The effectiveness of the proposed system is verified by simulation and experimental results. This result shows highly characteristic speed estimation and robust character of load regulation. and the flux which it follows in change of parameter and speed presumption it was under simulation and get the good result which it comes to get it analyzed.
A Study on Security of AMI(Advanced Metering Infrastructure) in SMARTGRID
Kim, Yeoun-Soo ; Kim, Jin-Cheol ; Ko, Jong-Bin ; Shon, Tae-Shik ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1014~1023
DOI : 10.12673/jkoni.2012.16.6.1014
Recently with improvement of SMART Grid, AMI network security has been affecting the environment for Electric information and communication. The system and communication protection consists of steps taken to protect the AMI components and the communication links between system components from cyber intrusions. The addition of two way communications between SUN and HAN introduces additional risk for unauthorized access to the AMI system. In this paper, we propose new AMI device authentication infrastructure, key establishment and security algorithm based on public key encryption to solve AMI network security problems.
A Study for Operation Technique Plan of Low-Cost UAV Data Bus
Gil, Hyun-Cheol ; Ahn, Dong-Mhan ; Hong, Gyo-Young ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1024~1031
DOI : 10.12673/jkoni.2012.16.6.1024
In the past, the part of development of that is used for the military aviation target or reconnaissance is being extended to the range of application not only reconnaissance but also civilian industry as the introduction of the newest IT technology and the technical evolution. The Civilian low-cost UAV that is expected growth at the market of UAV in the world is accelerated to the extended applicability in the fields. However, The UAV study is recently focused on the Link and The Data bus because the main decision of the civilian UAV system configuration is not suitable to determinate the factory of price. In this paper is analysed the UAV data bus through the simulation in same condition both the CAN Bus which used the automobile industry and the MIL-STD-1553B which is used the aviation industry. As a comparison result, we identified that the CAN Bus of conventional configuration is possible to transmit the data without the need for a separate coupler equipment against the MIL-STD-1553B data. Thus, we identified that the CAN bus is capable to apply as a low-cost UAV internal data bus to optimize configuration and weight than 1553B.
The Study on Marker-less Tracking Algorithm Performance based on Mobile Augmented Reality
Yoon, Ji-Yean ; Moon, Il-Young ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1032~1037
DOI : 10.12673/jkoni.2012.16.6.1032
Augmented reality (AR) is augmented virtual information on the real world with real-time. And user can interact with information. In this paper, Marker-less tracking algorithm has been studied, for implement the augmented reality system on a mobile environment. In marker-less augmented reality, users do not need to attach the markers, and constrained the location. So, it`s convenient to use. For marker-less tracking, I use the SURF algorithm based on feature point extraction in this paper. The SURF algorithm can be used on mobile devices because of the computational complexity is low. However, the SURF algorithm optimization work is not suitable for mobile devices. Therefore, in this paper, in order to the suitable tracking in mobile devices, the SURF algorithm was tested in a variety of environments. And ways to optimize has been studied.
High-Tunable Capacitor Using a Multi-Layer Dielectric Thin Film for Reconfigurable RF Circuit Applications
Lee, Young-Chul ; Lee, Baek-Ju ; Ko, Kyung-Hyun ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1038~1043
DOI : 10.12673/jkoni.2012.16.6.1038
In this work, a high tunable capacitor using a multi-layer dielectric of BZN/BST/BZN is designed and characterized for reconfigurable RF applications. By utilizing a high tunable BST ferroelectric and a low-loss BZN paraelectric thin film, a multi-layer dielectric of BZN/BST/BZN obtained a tunability of 47 % and
of 0.005. The fabricated tunable capacitor on a quartz wafer using this multi-layer dielectric achieved a Q-factor of 10 and tunability of 60 % at 800 MHz and 15 V. Its size is
7bits Hangul Jamo Coding system to consider of HDB-3 Data transmission processing efficiency
Hong, Wan-Pyo ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1044~1051
DOI : 10.12673/jkoni.2012.16.6.1044
This paper proposed a new Hangul Jeongum Jamo coding system. To do it, the current Hangul Jeongum coding system was analyzed with the source coding rule of character. As a result of the study, the current Hangul Jeongum coding system should be changed because there are many violated codes in the coding system. When the proposed coding system for Hangul Jeongum coding system is applied, the datacommunication efficiency could be increased to 19.78%.
The Influence of LMX and TMX on team effectiveness and team performance in Airline cabin crew team
You, Jung-Yun ; Lee, Mi-Hye ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1052~1064
DOI : 10.12673/jkoni.2012.16.6.1052
In this study for the purpose of providing the basic data for airline cabin service improvement and efficient crew management. The relationship on team effectiveness and team performance according to the quality of airline cabin crew team LMX(Leader-Member Exchange) and TMX(Team-Member Exchange) was verified. The findings from the analysis shows the closer team leader and team members have quality exchange relationship the more the cabin crews will team commitment and team satisfaction. The conclusion is drawn that increased team effectiveness(satisfaction and commitment) enhances team performance as well. Therefore, based on the results of the study on airline cabin crew team operation system, the team leader and team members should come up with specific scheme to establish quality exchange relationship and to maintain the relationship.
Adjustable Influence of the Converting Cost in Customer Satisfaction and Customer Preference Affected by the Main Factors of Airline Services
Chung, Yang-MI ; Lee, MI-Hye ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1065~1079
DOI : 10.12673/jkoni.2012.16.6.1065
This research is done with the objectives to examine and to identify how the main factors of airline services, which become fundamentals for airline customers to select their favorite one, affect their customer satisfaction and their customer preference, with a focus on adjustable influence of converting cost. The survey has been conducted with the population of the airline customers who use international airlines through Incheon International Airport and processed with the objectives to verify the influence of the main factors of airline services to customer satisfaction and customer preference and also to collect the verified data for adjustable influence of converting cost between customer satisfaction and customer preference, and its results are as follows: Firstly, airline services have significant impact on their customer satisfaction. Secondly, they also have significant impact on their customer preference, Thirdly, the converting cost between both of customer satisfaction and customer preference to airline services doesn`t involve the adjustable function in consecutive cost nor in learning cost but it does involve the one in sunk cost.
A study for Factors Affecting of Information Systems Audit Quality
Jeon, Soon-Cheon ; Choi, Sang-Kyoon ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1080~1091
DOI : 10.12673/jkoni.2012.16.6.1080
Information system for audit target that was done in the past business unit system presided over the development process for an integrated information system in three steps further from the audit step 2 step-by-doing, for in the presiding quality party check for the information systems audit requirements of social responsibility is growing. Therefore, efforts are needed for research on factors affecting the quality of the audit and audit improve the quality in order to improve the quality of the Methodist This study, the general auditor competence and supervision, empowerment and the causal relationship between the quality of service, presided over by a model that can be analyzed in the field to develop and take advantage of the auditor`s general theory of leadership was developed from existing research capabilities identification and analysis on a supervisor`s empowerment survey conducted for the auditor to perform Methodist, its contents and using the LISREL structural equation methods were empirically tested.
Implementation of the Aural Cueing System(ACS) for Applying the Reconfigurable Tactical Flight Training System(RTT)
Hong, Seung-Beom ; Ahn, Dong-Man ; Jie, Min-Seok ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1092~1100
DOI : 10.12673/jkoni.2012.16.6.1092
In this paper, it has designed and developed the integrated aural cueing system(ACS) system of the reconfigurable tactical Flight Training System(RTT) for the 6 rotorcraft such as UH-1H, UH-60, AH-1H, 500MD, BO-100, and CH-47. RTT is an evolving alternative instructional training system to provide the ability to rehearsal and collectively train, through networked simulators in a unit-collective and combined arms simulated battlefield environment. ACS handles the volume, pitch and repetition of the digitally stored sounds based on commands it receives from the Host server. This paper explained and implemented the conceptual and detail design the ACS system. In order to evaluating the performance of the ACS system, we made the monitoring system for interworking the virtual Host and the ACS system. As the result, it was confirmed the good performance.
Robust Real-Time Lane Detection in Luminance Variation Using Morphological Processing
Kim, Kwan-Young ; Kim, Mi-Rim ; Kim, In-Kyu ; Hwang, Seung-Jun ; Beak, Joong-Hwan ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1101~1108
DOI : 10.12673/jkoni.2012.16.6.1101
In this paper, we proposed an algorithm for real-time lane detecting against luminance variation using morphological image processing and edge-based region segmentation. In order to apply the most appropriate threshold value, the adaptive threshold was used in every frame, and perspective transform was applied to correct image distortion. After that, we designated ROI for detecting the only lane and established standard to limit region of ROI. We compared performance about the accuracy and speed when we used morphological method and do not used. Experimental result showed that the proposed algorithm improved the accuracy to 98.8% of detection rate and speed of 36.72ms per frame with the morphological method.
Design and Implementation of Fuzzy-based Menu Recommendation System
Kim, Hye-Mi ; Rho, Seung-Min ; Hong, Jin-Keun ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1109~1115
DOI : 10.12673/jkoni.2012.16.6.1109
In this paper, we propose a system that recommends the appropriate menu using the fuzzy rules and the case database. The rules are defined by using the user`s body information such as height and weight and these information is often vague. Due to its fuzziness, we use the fuzzy logic to represent the information. In our system, it firstly gets the body information for computing the BMI (Body Mass Index) values. Then it combines the muscle mass factor and BMI values to make a fuzzification for calculating the obesity rate. It finally recommends the most relative menu by comparing with the user`s obesity rate from each cases in the database. We implement the system on the Android platform and show that our proposed method can achieve reasonable performance through the various experiments,
Linear Relationship between Expenditure on intangible capital and Sales - aviation service and related manufacturing firms
Kim, Jeong-Yeon ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1116~1122
DOI : 10.12673/jkoni.2012.16.6.1116
Many researches predicted the linear relationship between discretionary expenditure and sales amount in manufacturing companies. We review their relationship based on financial reports of KOSDAQ and KOSPI listed companies in category of non-durable goods. Also we review the relationship between expenditure on intangible capital and sales amount in aviation service and related manufacturing firms. Identified manufacturing firms showed linear relationship between R&D expenditure and sales amount. On the contrary, aviation service and related manufacturing companies do not have linear relationship between expenditure on intangible capital and sales, while their general management and sales expenditure has linear relationship with sales. It shows aviation service and related manufacturing company keep advertising or R&D related expenditure as sales revenue decreases, while manufacturing companies of non-durable goods has a tendency to reduce it as sales revenue decreases.
A study on MRAS(Model Reference Adaptive System) Method Instantaneous Speed Observer for Very Low Speed Drive of Induction Motors
Hwang, Lark-Hoon ; Na, Seung-Kwon ; Chung, Nam-Kil ; Kim, Young-Bog ;
The Journal of Advanced Navigation Technology, volume 16, issue 6, 2012, Pages 1123~1133
DOI : 10.12673/jkoni.2012.16.6.1123
This study configuration Vector Control System which is stable and has outstanding Dynamic Characteristics in Very Low Speed Region and Low Speed Region, and proposes Instantaneous Speed Observer and Very Low Speed Control method and vector control system of the speed estimation a using Reduced-Dimensional State Observer. The Observer proposed in this system, by appling Reduced-Dimensional State Observer to Load-Torque estimation and using for speed estimation, implements system composition simply and is capable of accurate Instantaneous Speed estimation in Very Low Speed Region. Also, this study reduces influence by System Noise and suggests an induction motor speed control system which is effective in Load Disturbance, modeling error, estimation noise and so on without changing pole of an Observer.