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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of the Korean Society of Safety
Journal Basic Information
Journal DOI :
The Korean Society Safety
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Volume & Issues
Volume 16, Issue 4 - Dec 2001
Volume 16, Issue 3 - Sep 2001
Volume 16, Issue 2 - Jun 2001
Volume 16, Issue 1 - Mar 2001
Selecting the target year
Emission Characteristics of LP Gas Burner for the Variation of Combustion Conditions
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 1~6
An experimental study was carried out to investigate the emission characteristics of LP gas burner for the Practical combustion conditions including fm voltage, inlet area, gas Pressure, emission resistance, duct length and height. The result shows that CO is almost remains constant for the emission fan voltage, but significantly increases with the reduction rate of air inlet, up to 3000ppm at 50% of reduction rate. Also, the variation of gas pressure has no effect to CO of gas boiler due to its governor which controls gas pressure secondly, but it gives an rapid increase of CO for the gas range. The emission resistance test shows that CO is suddenly increased with the reduction rate of emission duct above 70% and main burner is stopped at 90%. The reverse wind test shows that CO is suddenly increased with the air velocity above 7m/s and main burner is stopped at 9m/s. The more horizontal length of emission duct is long and the vertical height is low, CO is infinitesimally increased
Characteristics in W-EDM of Tungsten Carbide
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 7~13
Wire electrical discharge machining experiments in conducted to investigate characteristics of acoustic emission (AE) and electrical discharge energy due to current peak (I
), pulse on time(
/on/). The AE signals are obtained with a sensor attached to workpiece side. Machining states are identified with scanning electron microscopy and residual stress analyzer. It is demonstrated that the residual stress provide reliable informations about the machining states. Moreover, machining states can be detected successfully using both the residual stress and AE count rate.e.
A Study on the Fracture Resistance Curve and Effect of Side Grooves of SG365 Material
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 14~21
SG-365 steel is an important material End used for manufacturing a pressure vessel and gas piping. In this investigation, the elastic plastic fracture toughness of this material is evaluated by the unloading compliance method according to the ASTM E8l3-97 and E1152-97 method on the smooth and side groove In specimens. The effect of smooth and side groove is studied on the elastic plastic fracture toughness. The side grooved specimen is very useful in estimation of the
. Because it is much easier than the smooth specimen to the onset of the ductile tearing by the R curve method. Besides. it improves the accuracy of toughness values, decreases the scattering of them and crack tunneling effect and shear lip by the side groove.
A Study on the Characteristics of Pressure Distribution for Heat Exchanger Types of Domestic Gas Boiler
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 22~28
Heat transfer and pressure distribution for heat exchanger type of domestic gas boiler are different from shape, pitch, thickness of fin and array of pipe respectively. In order to measure the pressure distribution across the heat exchanger, a suction type wind tunnel was constructed and velocity distribution was measured for pilot tube(4 point) of rack type. The experiments were performed for 5 different air flow mass, rpm=3,6,9,12,15 and transverse axis of heat exchanger(x-length) is 5cm respectively. Results showed that above 9.5m/s, pressure distribution dispersion for wet type of heat exchanger is on the increase and above 5.5m/s, pressure distribution dispersion for dry type of heat exchanger is on the increase. Also, pressure distribution dispersion by comparing two different types heat exchanger, dry type of heat exchanger showed a higher augmentation than wet type of heat exchanger.
Fracture Mechanics Analysis of a Reactor Pressure Vessel Considering Pressurized Thermal Shock
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 29~38
The purpose of this paper is to evaluate the structural integrity of a reactor pressure vessel subjected to the pressurized thermal shock(PTS) during the transient events, such as main steam line break(MSLB) and small break loss of coolant accident(SBLOCA). For postulated surface or subsurface cracks, variation curves of stress intensity factor are obtained by using the three different methods, including ASME section XI code anlysis, the finite element alternating method and the finite element method. From the stress intensity factor curves, the maximum allowable nil-ductility transition temperatures(RT/NDT/) are determined by the tangent criterion and the maximum criterion for various crack configurations and two initial transient events. As a result of the analysis, it is noted that axial cracks have smaller maximum allowable RT
values than same-sized circumferential cracks for both the transient events in the case of the tangent criterion. Axial cracks have smaller RT
values than same-sized circumferential cracks for MSLB and circumferential cracks have smaller values than axial cracks for SBLOCA in the case of the maximum criterion.
Fracture Characteristics of D 3507 and D 3631 City Gas Steel Pipes
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 39~46
It is noted that KS D 3507 pipe steel has several problems when it is used as a city gas pipe at medium pressure. So new pipe steel, KS D 3631, was developed in order to be used as a pipe for medium and low pressure and now it is being substituted for D 3507. In this study, several mechanical tests, such as tensile test, microhardness test, and Charpy impact test were conducted to get material properties of D 3507 and D 3631 pipe steels. And also microstructures at the weld and heat affected zones were observed for the two materials. From the Charpy test results
was estimated for the upper and lower shelf and the critical crack length is calculated for supposed axial semi-elliptical surface cracks. And the burst pressure is estimated as a function of wear depth for a defective D 3631 pipe by using the finite element method. The burst pressure is also calculated for pipes with an axial crack by using the published equations.
The Damage Evaluation for the Application of Acoustic Emission in a Drilling Procedure of the CFRP Composite Materials
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 47~51
The carbon fiber reinforced plastics(CFRP) have been widely used in aircraft and spacecraft structures as well as sports goods because it has high specific strength, high specific stiffness and low coefficient of thermal expansion. Machining of CFRP poses problems not frequently seen for metals due to the nonhomogeneity, anisotropy, and abrasive characteristics of CFRP. Delamination is a common problem faced while drilling holes in CFRP using conventional drilling. Therefore, AE characteristics related to drilling damage process of unidirectional and [0/90/]s crossply laminate composite was studied. Also drilling damage like the delamination was observed by video camera in real time monitoring technique. From the results, we basically found the relationships between the delamination from drilling and AE characteristics for CFRP composites.
A Study on the Fatigue Crack Growth Behavior in Ti-6Al-4V Alloy(I)
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 52~57
Fatigue crack growth behaviour of Ti-6A-4V alloy is investigated in air and salt solution environment at room temperature and
. Fatigue crack growth rate is blown to be fast for the formation of corrosive product in hot salt environment. For the effect on corrosion fatigue crack growth behaviour of region II. fatigue crack growth rate in atmosphere had a little gap to both case,
and room temperature. However, it showed very fast tendency in salt corrosive atmosphere, and it was remarkably accelerated in
temperature salt environment. When
K was approximately 30MPa(equation omitted), fatigue crack growth rate had a little difference between at room temperature and at
high temperature, however in case of salt corrosive environment the room temperature was 3.5 times Inter and
high temperature for 16 times than air environment respectively.
A Study on the Prediction of Welding Residual Stresses and the Selection of Optimal Welding Condition using Neural Network
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 58~64
In this study, it is developed that the system for effective prediction of residual stresses by the back-propagation algorithm using the neural network. To achieve This goal, the series experiment were carried out and measured the residual stresses using the sectional method. Using the experimental results, the optional control algorithms using a neural network should be developed in order to reduce the effect of the external disturbances during GMA welding processes. Then the results obtained from this study were compared between the measured and calculated results, weld guality might be controlled by the neural network based on backpropagation algorithm. This system can no only help to understand the interaction between the process parameters and residual stress, but also improve the quantity control for welded structures.
A Study on Fatigue Analysis, Reliability and Life Expectancy of a Double Link Type Level Luffing Jib Crane
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 65~73
This paper is a study on the fatigue analysis using BS5400 Part10(1980), code of practice for fatigue for a double link type level luffing jib crane which has been operated since the crane was built in 1985 at a domestic pier. South Korea. In addition, on the basis of the design lift due to fatigue analysis and the number of cracks detected from the nondestructive test the structural reliability and the residual life of the crane is predicted by evaluating the expected development of detectable fatigue oracle during the next five to ten years using Paris's Law for predicting fatigue crack growth and Gaussian probability density function to be reasonable for stress ranges below the mean values determined by laboratory tests. The statistical data used for the analysis of the structural reliability and life expectancy is given in the above referred code.
An Evaluation of a Direct Numerical Simulation for Counterflow Diffusion Flames
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 74~81
A direct numerical simulation (DNS) was applied to nonpremixed counter-flow diffusion flames between oxidizer and fuel ducts. The objective of this study is to evaluate the numerical method for simulation of axisymmetric counterflow diffusion flames. Effects of computational domain size and grid size were scrutinized, and then the method was applied to air-methane diffusion flames. The results at zero gravity conditions were in good agreement with those obtained by the one-dimension flame code OPPDIF. It was confirmed thai the numerical method is applicable to the diffusion flames at the normal gravity conditions since the results clearly showed the effects of buoyancy and velocity ratio.
A Study on the NOx Emission Characteristics in Parametrically Varied Laminar Hydrogen-Air Coflow flames
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 82~87
The NOx emission characteristics of jet flames fueled with It was studied. Experimental and numerical investigations were carried out for various flames with varying equivalence ratio, fuel flow rate and nozzle diameter. The Emission indices of NOx(EINOx) were measured by chemiluminescent method and calculated by simulation using detailed chemistry. The results show that the numerical results represent well the trends of EINOx experimentally observed. EINOx of H
flame steeply increase at small equivalence ratio, gently increase and steady at more than equivalence ratio is 4.0. EINOx trends of H
flame can be describe in function of residence time in the high-temperature region weighted by the maximum flame temperature.
Efficiency Optimization Control of Induction Motor using Adaptive Flux Observer
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 88~95
Stator core loss has significant adverse effects when an induction motor is controlled by the conventional vector control method. Therefore, taking core toss into account should make it possible to control the torque very precisely. This paper proposes a speed sensorless vector control method for an induction motor at optimum efficiency and high response taking core loss account. The proposed vector control system consists of a speed adaptive rotor flux observer which takes core loss into account and employs a direct vector control which compensates for the influence of core loss. Also, in this paper, a vector controlled induction motor with a deadbeat rotor flux controller is developed. The method ensures optimum efficiency in the steady state without degradation of the dynamic response. The validity of the proposed technique is confirmed by simulation results for induction motor drive system.
A Study of Ground System improvement on Isolated Power Generation
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 96~102
In construction sites, portable generators and electrical equipments cause frequently electrical accidents due to the poor condition of their usage. However, there are very few technical guidelines on these equipments even though they have serious accident causing potentiality. In order to reduce such accidents in practical and economical, grounding methods are studied in this paper as the countermeasure of electrical accidents. Several Korean national standards and international standards regarding three grounding types are compared each other, and some prevention means of electrical accidents are reviewed in this study. This paper presents the most effective grounding methods by assuming the WCS with the isolated power systems.
A Study on Explosive Limits of Flammable Materials - Explosive Limits of Flammable Binary liquid Mixture by Liquid Phase Compositions -
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 103~108
Explosive limit is one of the major physical properties used to determine the fire and explosion hazards of the flammable substances. Explosive limits are used to classify flammable liquids according to their relative flammability. Such a classification is important for the safe handling of flammable liquids which constitute the solvent mixtures. Explosive limits of all compounds and solvent mixtures can be calculated with the appropriate use of the fundamental laws of Raoult, Dalton, Le Chatelier and activity coefficient models. In this paper, Raoult,s law and van Laar equation(activity coefficient model) are shown to be applicable for the prediction of the explosive limits in the flammable ethylacetate-toluene system. The values calculated by the proposed equations were a good agreement with literature data within a given percent. From a given results, by the use of the proposed equations, it is possible to predict explosive limits of the other flammable mixtures. It is hoped eventually that this method will permit the estimation of the explosive Properties of flammable mixtures with improved accuracy and the broader application for other flammable stances.
A Study on the Explosion Characteristics of City Gas
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 109~114
Explosive characteristics of the city gas were determined by using the gas explosion apparatues. The explosive range is determined between lower explosive limit of 5.0% and upper explosive limit of 15.3% at atmosphere and even though the oxygen concentration is decreased, lower explosive limit is not changed, but upper explosive limit is rapidly decreased. The minimum oxygen for combustion is determined 10%. The maximum explosion pressure is determined 5.72
and the maximum rate of explosion pressure rise is oxygen concentration of 12% to determined 160.12
Trend Analysis for Risk Management of Construction Project using P.M.I. Techniques
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 115~122
Recently construction enterprises involves more occurred with increase of size and complxity of construction works. Risk management is one of the key project management process. Numerous tools are available to support the various phases of the risk management process. We present the results of a study designed to identify the tools that are most widely used and those that are associated with successful project management in general, and in effective project risk management in particular. The study is based on a questionnaire administered to a sample of project managers from construction enterprises. The response data was analyzed in order to find which tools are mon likely to be used in the those organizations that report better project management performance and in those that value the contribution of risk management processes.
A Study on Effect of Pre-Stressing Sequences in PSC Bridge Strengthening Method Using Continuity with External Prestressing
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 123~127
Numerous PSC bridges are stregthened by the combined use of continuity of simple spans and addition of external prestressing. In this case prestressing sequences should be carefully checked due to the effect on the stress and camber of girders and slab. Various prestressing sequences were applied in this field test and measured values were analysed. This results show that preatressing sequences affact the stress and deflection of bridge members, so the prestressing sequence should be considered at the desist and construction stages of deteriorated bridges.
A Study on the Stability of Anisotropic Circular Conical Shells
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 128~133
In this paper, stability analysis is carried out far the out of plane behaviors under compressive loads to the conical direction. It is not easy to obtain the analytic solutions about the stability analysis of anisotropic conical shells consisted of composite materials. For solving this problems, this paper used the finite difference method which is one of the numerical methods. The characteristics of the buckling behaviors of anisotropic laminated composite conical shells may be different according to a variety of causes, that is, the change of fiber angle, material arrangement, radius ratio, shape ratio and so on. The objective of this study is to analyze buckling behaviors of circular conical shells with shear deformation effects and to prove the advantage of composite materials.
A Study on the Effectiveness of the Risk Assessment Regulations for Construction Works
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 134~139
The Risk assessment regulation(RAR) is one of the essential articles of the Occupational safety and health law for the construction industry along with safety and health management expense and safety organization regulation. However, arguments regarding the working time of the safety assessment documents, the person in charge of documentation, weakness in legislative enforcement etc. are ongoing. Thus this study aims to analyze the effectiveness of RAR for the guidance of enhancing the effectiveness of RAR. The findings are; 1) the effectiveness of RAR is recognized, however the indirect effectiveness ie, enforcement of safety activities, previewing of drawings etc. are bigger than the direct effectiveness of accident prevention, 2) to enhance the effectiveness of RAR site inspection procedure has to be utilized, 3) further research for identifying and getting rid of negative factors in RAR is recommended.
Development of the Construction Safety Information System
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 140~146
In construction industry, workers' accident rates are relatively high compared to those of other industries. These high accidents rates are mostly due to the characteristics of construction process. In order to effectively reduce the accident rates, it is required to develop not only immediate measures but also long-term programs of instruction, training, and education. In addition, well-analyzed information on past history is required for the prevention of accidents. By examining about 800 cases of construction accidents that happened between Jan. 1992 and Dec. 2000, this paper developed an information system that provides appropriated safety information to the construction workers. This system is expected to contribute to the workers' safety in construction industry.
Structural Analysis for the Collapse Accident of Tower Crane
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 147~152
The tower cranes are the very useful construction machine in the high place works. But they are very susceptible to the load balance, the wind load and the hanging load because they are the very slender structures and those center of gravity is located in the upper part. Therefore, the collapse accidents of tower one have repeatedly happened during the assemble or disassemble works. The correcting frame may has often used in order to correct the error in the setting of foundation anchors. The goal of this study is that propose the methods preventible the collapse accident of tower crane which is constructed by using the correcting frame. In order to accomplish the goal of this study, the field survey, the reference investigation and the structure analysis were performed for the collapse accident of tower crane using the correcting frame. This study result in the methods preventible the same accident.
Construction Techniques for Crack Control of Underground Box Structures
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 153~159
Recently, the underground reinforced concrete(RC) box structures have been increasingly built in Korea. In such structures, the heat of hydration may cause serious cracking problems. The RC box structures are classified in this category that needs much attention to control the hydration heat during construction, which causes the restraining effects on the boundaries. The purpose of the present study is to develop the rational construction method to control the thermal cracking problem of the box structures. In this study, the causes and mechanism of thermal cracking according to construction stages in the RC box structures are thoroughly analyzed. The major influencing variables are studied through the finite element analysis which affect the thermal cracking of RC box structures. The research results of the present study can be efficiently used for the control of cracking of box structures during construction stages.
Sensitivity Study of Thermal Stresses in Mass Concrete Structures
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 160~167
Cracking in connote structures is one of the main issues of structural design next to ensuring the load-bearing capacity. Thermal analysis is used to prevent thermal mucking, but concrete properties are uncertain variable, and analysis results have uncertainty, too. In this study, sensitivity analysis is performed to investigate the effect of conductivity, specific heal and pouring temperature. The results show that lower conductivity and higher specific heat increase the maximum temperature and maximum tensile stress. The structure with internal restraint is mostly influenced by the change of conductivity and specific heat.
Development of a Task Analysis Method and Classification of Emergency Tasks for Human Error Analysis in Nuclear Power Plants
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 168~174
For human error analysis, the structure and situation of a task should be analyzed in advance. The paper introduces Structured Information Analysis (SIA) as a task analysis method for error analysis, and delineates the result of application on the emergency procedure of Korean Standard Nuclear Plants (KSNPs). From the task analysis about emergency procedure of KSNP, total 72 specific task goals were identified in the level of system function, and 86 generic tasks were classified from the viewpoint of physical sameness of the task description. Human errors are dependent on task types so that the result of task analysis would be used as a basis for the error analysis on the emergency tasks in nuclear power plants.
The Importance of Self-Inspection in Accident Prevention
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 175~181
In compliance with the Industrial Safely and Health Acts, the owners/users have performed self-inspection at regular intervals to secure safety in the use of hazardous machinery, equipment and facilities However, securing safety, which is the goal of self-inspection, has not been thoroughly understood in most small businesses and factories. The objective of this research is to analyze the importance and effects of self-inspection in preventing accidents in businesses and factories that use hazardous machinery and facilities. The result shows that self-inspection has made a good contribution to the prevention of accidents. Most businesses and factories that responded the survey answered they have improved safety in the use of machinery and facilities through self-inspection, though the ways of self-inspection were not all the same. However, the result also reveals that there are rooms for further improvement in the areas of self-inspection intervals, self-inspection methods and the selection of self-inspection objects. This improvement is necessary to improve the effect of self-inspection and to minimize regulations of the government on business activities.
The Influences of Whole-body Activity on Reaction Time and Mental Work Using Treadmill-eqipped Instrument
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 182~187
This paper examines the effects on human reaction time and mental fatigue of changes in the intensity of physical activity. A treadmill-equipped instrument and perception tester were used to attain several levels of physical activity. In this paper, in order to determine the individual levels of physical activity of subjects, Borg-RPE scale, Heart Rate(HR) and Respiratory Quotient(RQ) were used. Also, a reaction test in whole-body activity on treadmill-equipped instrument and an addition test as an indicator of mental fatigue were performed. In the above experiments, the scores obtained in addition test administered before and after Physical activity at each intensity level used. Restricted within the limits of this paper, the results of these tests showed that mental fatigue decreased after physical activity.
Suggestions for Counterplans in the area of Industrial Safely for the Product Liability Act
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 188~193
From July 1st 2002, the Product Liability Act will be efficacious in Korea, and its influence will be prevalent over all industrial folds. However, little attention has been paid to the Act and its influence in the area of Industrial Safety. Therefore, this paper aimed to call the people's attention to them, and to suggest some points for counterplans in that n As for counterplans to the Product Liability, there are two different approaches - Product Liability Prevention (PLP) and Product Liability Defense(PLD). Between them, PLP is more safety-oriented approach, and especially Product Safety(PS) will be the core of it. Related with this, it was noted that productive goods which are utilized as productive materials or tools in the later process or industries could be troublesome when the Act is efficacious. As a solution, the necessity of cooperation among manufacturing plants belong to the similar industry, and of development of qualitative techniques applicable to analyses of consumers behavior was emphasized. Ant the interest and participation of Human Behavioral Scientists, Ergonomists as well as Consumer Psychologists were called upon. Also, it was suggested that an integrative approach including administrative or governmental management system for industrial goods should be developed.
Variation Trends of Population and industrial Accidents involved Middle-aged & Aged Workers in Recent Years
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 194~199
The present situation of Korea already shone various symptoms of the aged society, and many kinds of data reported by the National Statistical Office demonstrate those facts. However, to my regret, sufficient efforts for aged workers are not taken in the area of industrial safety. In this research, work arrangement and industrial accidents of middle-aged and aged workers over last 5 years were analyzed. According to research results, proportion of industrial accidents involved middle-aged and aged workers was as high as 40%, and that of aged workers alone was so high as 25%. In addition, proportion of accidents were higher than that of worker population f3r aged wetters. Considering ages, it was demonstrated that as workers get older, mean number of accidents shows the tendency of going higher, and that as years go by, mean lost work-days are increasing regardless of age group. Main accident types were Fall followed by Slip, and Work-Related Disease, furthermore proportion of Slip was highest than any other types for aged workers. Based upon these results, it was emphasized thai careful attention should be paid to functional characteristics of aged workers, and that modification of accident prevention policy would be necessary
Power Transmission from a Vibrating Mass to a Supporting Elate through Isolators
Jin-Woo Lee ; Colin H. Hansen ;
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 200~207
The transmission of harmonic vibratory power form a vibrating rigid body into a supporting plate through passive and active isolators is investigated theoretically and experimentally. The theoretical model allows for the transmission of vertical and horizontal harmonic forces and moments about all three coordinate sun. The experiment is to use vibration actuators attached to the intermediate mass of the two-stage mount to minimize the rotational and translational vibration of the intermediate mass. The performance is done by measuring the vibration at the error sensors due to the primary vibration source and measuring the transfer functions from the control sources to the error sensors. Results show that over a frequence range from 1 to 100Hz, transmission into the supporting plate can be reduced substantially by employing in parallel with existing passive isolators, active isolators adjusted to provide appropriate control force amplitudes.
Stress Analysis of Helical Spring Using DQM
Ki-Jun Kang ;
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 208~212
DQM(differential quadrature method) is applied to computation of two dimensional elasticity problems in helical spring. Elastic shear stresses in an axially loaded helical spring having rectangular and square cross sections are calculated. The results are compared with those obtained using the method of successive approximations. The differential quadrature method gives good accuracy even when only a limited number of grid points is used.
Web-based Predictive Maintenance(PM)
Gi-Heung Choi ;
Journal of the Korean Society of Safety , volume 16, issue 4, 2001, Pages 213~217
Requirements for Device Networks differ greatly from those of typical data networks. Specifically, any device network technology which employs a fieldbus protocol is different from IP network protocol TCP/IP. In general, one needs to integrate fieldbus protocol and TCP/IP to realize device network over IP network or internet. Interoperability between devices and equipments is essential to enhance the quality and the performance of predictive maintenance(PM). This paper suggests a basic framework for web-based predicted maintenance and a method to guarantee interoperability between devices and equipments.