• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 B
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• pp.733-734
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• 2006

In this parer, characteristics of the flexible rail in levitation control system are analysed. The magnetic levitation system is an electromagnet type and is full-scaled vehicles. The system consists of electromagnet, chopper, flexible rail, secondary suspension system and levitation controller. The mathematical modelling for the whole system is carried out. Especially, the flexible rail is modelled using second-order mass-spring-damper system. Using the derived model, the dynamic characteristics for the system are presented with different vehicle speed.

• Asian Journal of Business Environment
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• 제6권4호
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• pp.27-34
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• 2016

Purpose - The study sought to examine the relationship between individual characteristics and system features and Human Resource Information System (HRIS) success in Japanese manufacturing companies in Malaysia. Research Design, Data, and Methodology - This study adopt quantitative approach to investigate the relationship between individual characteristics and system features and HRIS. Toward this objective, a total of 700 questionnaires were mailed to a representative of the organization. A total of 187 questionnaires were returned, and only 145 were usable for further analysis, representing a response rate of 20.71%. Result - Results indicated that individual characteristics and two dimensions of system characteristics (ease of use and training) were significantly related to HRIS success. Unexpectedly, the results showed that the third dimension of system features (documentation) was unrelated to HRIS success. Conclusions - The results partially support the underlying arguments that individual characteristics and system characteristics have significant influences on HRIS success. The finding suggests that HRIS success in the organization can be generated as a result of good implementation of system support and employees' readiness to apply HRIS in their jobs.

• 조명전기설비학회논문지
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• 제12권4호
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• pp.75-80
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• 1998

본 논문에서는 DSP 장치와 개인용 컴퓨터를 연계한 실시간 인버터 특성 분석 시스템을 제안하였다. 전력 변환 시스템은 제어 대상과 용도에 따라 회로를 셜계한다. 그리고 설계된 전력 변환 시스랩은 입력 조건에 따라 시스템의 제어특성이 평가된다. 따라서 제어방법을 연구하기 위해서는 전력 변환 시스템이 필요하고, 이를 평가하기 위한 관측 시스랩이 필요하다. 제안한 실시간 특성 분석 시스랩을 평가하기 위하여 인버터 시스템을 구성하였다. 그리고 개인용 컴퓨터를 이용하여 입력 제어 조건에 따라 유도전동기를 구동하였다. 이때 얻어지는 인버터 출력 특성 및 제어특성올 다양하게 분석하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.717-720
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• 2002

An Amplitude Proportional Friction Damper (APFD) system is considered in order to improve the stick-slip characteristics of Coulomb friction damper. The frictional force is proportional to the amplitude in APFD system and the system is non-linear as is Coulomb damper system. The free vibration analysis on an 1-DOF system has conducted to demonstrate the characteristics of the APFD system and the results show that the APFD system has similar damping characteristics to the viscous damper system. It is concluded that the APFD system may become a cost effective substitution for the viscous damper and it also has certain advantages over Coulomb damper system since the APFD system can be designed to work with no stick-slip.

• 한국시스템다이내믹스연구
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• 제11권2호
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• pp.5-28
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• 2010

The purpose of this paper is to review relationship between spatial characteristics of compact city and urban sustainabiliy from system dynamics perspective using causal loop analysis. It has been argued that spatial characteristics of compact city, high population density and mixed land use, are positively related to urban sustainability. However, research results that are not consistent with pros of compact city argument have been accumulated too. It is especially true when spatial characteristics of compact city are examined with regard to each dimension of sustainablility: economic, social, and environmental sustainability. Reviewing each dimension of sustainability with regard to spatial characteristics based on causal loop analysis, this paper provides more clear understanding on relationship between compact city and sustainability. Also this paper provides a base for system dynamics simulation for future study.

• 한국분무공학회지
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• 제15권1호
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• pp.8-16
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• 2010

This paper present the diesel spray characteristics at different injection system parameters in a HSDI diesel engine. The spray characteristics was calculated by the coupled simulation of fuel injection system model and three-dimensional KIVA-3V code with TAB spray model. The relevant injection parameters are accumulator volume, control chamber initial volume, control orifice diameter, needle valve diameter and nozzle chamber initial volume, etc. Parametric investigation with respect to twelve relevant injection parameters showed that there was a significant advantage in varying control chamber initial volume, control chamber orifice diameter, and nozzle chamber orifice diameter with respect to effect the SMD and fuel injection speed. Consequently, in order to design the fuel injection system for spray characteristics, it seems reasonable to suppose to be optimized the fuel injection system.

• 한국문헌정보학회지
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• 제27권
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• pp.291-339
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• 1994

The purpose of this study is to find personal characteristics that affect users' cognitive characteristics of system, and to verify correlations between this users' cognitive characteristics and selection of system usage in using end -user searching systems (EUSS), For corroborative analysis of this study, preliminary model was constructed referring to Davis' Technology Acceptance Model. The model consists of exogenous variables (personal characteristics) , parameter variables (perceived usefulness, perceived ease of use), and effect variables (selection of system usage), When exogenous variables affect parameter variables, exogenous variables are independent variables and parameter variables are dependent variables. In addition, in correlation of parameter variables, which have been affected by exogenous variables, with effect variables, parameter variables are independent variables and effect variables are dependent variables, As for the research methodology, this study regards the Academic Information System connected with the Internet as EUSS, So questionnaires have been sent to researchers in universities who were conducting direct searching for the system. 229 valid responses to questionnaires have been analyzed according to Pearson Correlation Analysis and Stepwise Selection of Multiple Regression in the statistical software packages, 'SPSS PC+'. The findings and conclusions made in this study are summarized as follows; 1. Among the personal characteristics (age, disciplinary, computer literacy level, perceived usefulness of use education and training, perceived satisfaction of end-user searching, perceived satisfaction of system characteristics), all characteristics but age affect perceived usefulness and perceived ease of use. Specifically, perceived satisfaction of end user searching and perceived satisfaction of system characteristics most affect perceived usefulness and perceived ease of use respectively. 2. Perceived usefulness and perceived ease of use have a direct effect on selection of system usage in using EUSS. 3, Perceived usefulness more affect selection of system usage than perceived ease of use in using EUSS.

• 한국유체기계학회 논문집
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• 제12권3호
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• pp.13-18
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• 2009

This paper describes flow characteristics in a piping system having various duct shapes on refuse collecting system. A simulator for the refuse collecting system is designed to analyze the flow characteristics in the piping system. The simulator consists of an air intake, a waste chute, circular duct having various shapes, cyclone and turbo blower. The simulator has four different duct shapes: straight, curved, inclined and Y-shaped ducts. Three-dimensional Navier-Stokes analysis is introduced to analyze the pressure loss in the piping system. Throughout the numerical simulation, pressure loss obtained by numerical simulation has a good agreement with the results of experimental measurements. The selected length of curved and Y-ducts for the pressure loss is determined using pressure distributions on the duct. Flow and pressure characteristics in the piping system of the simulator are evaluated by numerical simulation and discussed in detail.

• 한국국방경영분석학회지
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• 제5권2호
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• pp.27-38
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• 1979

This method explores a method of aggregating the measures of effectiveness of a weapon system from its characteristics. With this method, the constant sum method and multiple regression are used to develop a functional relationship between system effectiveness and system characteristics. As an example, a study of a tank weapon system was${\cdot}$conducted with data from the U.S. Army Armor School. It was concluded that the aggregation method is feasible, and that for the tank system studied, the reciprocals of system characteristics give a good estimating equation for measuring tank system effectiveness.

• 한국자동차공학회논문집
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• 제12권2호
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• pp.148-159
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• 2004

This paper discusses vibration mode of the drivesystem considered the vehicle body's dynamic characteristics to study the influence of the vehicle body's dynamic characteristics on the vibration mode of the engine mount system and the ride quality of a vehicle. The simulation model consists of the engine mount system, the powertrain and the rigid or elastic vehicle body. Variables used in this study are the stiffnesses of an engine mount system and the excitation forces. The Goals of the study are analyzing both the vibration transmitted to the vehicle body including the drivesystem and the influence of the vehicle body's dynamic characteristics on the engine mount system. The mode of drivesystems with a rigid and a elastic vehicle body was compared. From the result of the forced vibration analysis for the drivesystem with a elastic vehicle body, it is shown that the vehicle body's dynamic characteristics influence on the engine mount system reciprocally.