• Transactions of the Korean Society of Automotive Engineers
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• v.12 no.2
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• pp.175-181
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• 2004

Analysis of brake characteristics has progressed rapidly in recent years, as computer techniques have developed. However, there are many problems in predicting braking characteristics, due to the numerous design variables of the brake system. Therefore, a synthetic braking performance analysis is required for all brake system parts such as master cylinder, booster, control valve and split system. In this paper, a program which can analyze braking performance such as force distribution, braking efficiency, pedal force and pedal travel, is presented. The preprocessor of the program helps users prepare input files through a dialog box. An additional postprocessor makes the graph presentation of solved results. Also, a simple example problem is applied to show the usefulness of the presented program.

• Journal of the Korean Society for Aviation and Aeronautics
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• v.24 no.3
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• pp.10-18
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• 2016

This paper deals with the Performance Based Logistics(PBL) application scheme pertaining to optimal maintenance program for logistics of Korean Fighter Experimental(KF-X) Project. For enhancement of the performance based logistics system application to KF-X program the selection of appropriate standards fit to maximize cost-cutting, a set of performance metrics fit for the purpose of the contract, foreign technology dependence of core equipments and parts were considered. Thus, selecting appropriate standards fit for Korean logistics environment, domestic maintenance enterprise for stable rate of operation of KF-X, a systematic reliability task that is able to measure quantitative combat capability are suggested.

• Journal of Korea Technology Innovation Society
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• v.2 no.3
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• pp.1-18
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• 1999

The purpose of this research is to analyze the influence of the factors on the performance of na-tional R&D support program. A LISREL model was employed to analyze the relationship between the factors and the performance which was measured in the technological and commercial aspect. The result of the study reveals the R&D management business administration the age and the size of the company industry domain are the factors whose relationship with the performance are sta-tistically significant.

• Journal of Gifted/Talented Education
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• v.26 no.3
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• pp.427-447
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• 2016

The purpose of this study was to investigate science gifted education recipients' perception through importance-performance analysis regarding gifted education program, and explore reinforcements and improvements for providing an education program to meet the needs of science gifted. For this study, we developed an questionnaire and conducted a survey of 288 university students who had experience of receiving science gifted education. The collected data was analyzed by SPSS 20.0 in order to analyze difference between importance and performance which recipients perceived, paired t-test was conducted. Moreover, to investigate improvements for education program, Importance-Performance Analysis(IPA) was conducted. We deduced the following from the analysis. The performance is in general lower than the importance which recipients perceived regarding experienced education program. There was a differential needs in the type of education program depending on the school level. In other words, they were perceived 'education based on experiences' as effective education program for elementary school students; 'education based on inquiry activities' for middle school students; and 'education based on research activities 'for high school students. But, career education and leadership program was included in domain of urgent improvement regardless to the school level. This study has different signification from previous research in that was analyzed gifted education program considering the splashdown effect.

• Transactions of the Korean Society of Automotive Engineers
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• v.11 no.5
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• pp.147-155
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• 2003

The application of object-oriented modeling to develop a powertrain performance simulation program, called O-DYN, is introduced. Powertrain components, such as the engine, transmission, shaft, clutch are modeled as classes which have data and method by using object-oriented modeling methodology. O-DYN, a performance simulation program, based on the object-oriented modeling is made in C++. One powertrain simulation using O-DYN is proposed, and it is expected that the simulation program or individual class constructed in this paper would be useful for automotive engineers to predict the performance of powertrains and to develop a simulation program.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2009.05a
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• pp.414-416
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• 2009

In order to build a transient simulation program for a high thrust liquid rocket engine(LRE), a static performance simulation program for components were made. The components were the thrust chamber (combustion chamber and supersonic nozzle), centrifugal pump (impeller and volute casing), impulse turbine, and flow control devices (control valve and orifice). Simplified mathematical models based on classical thermodynamic and inviscid theories were used to remove complexity and enhance the utility of the program. We examined the results of each program qualitatively for validate each component modeling.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.4
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• pp.249-257
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• 2016

The purpose of this study is finding the key factors for navy to determine the necessity of naval ship PIP(Performance Improvement Program) against the altered battle field environment and politics. Recently, leading countries try to cope actively with the changing international circumstances and technology development trend in the commercial industry. In the case of domestic situation, based on the regulation, it is possible to modify the ship configurations by PIP, but there are not enough criteria and references to make a decision of necessity for the PIP program considering the naval ship acquisition planning by navy. It is necessary to acquire the obvious decision criteria for determination of PIP commencement, by the operational, political and security environment around the Korean peninsula. Considering these conditions, this study proposes the factors necessary for naval ship PIP for navy.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.03a
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• pp.499-502
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• 2008

This paper presents on research findings of how Visual C++ program can be used to generate codes capable of performing ramjet engine simulation To understand the diversity and applicability of this tool an arbitrary ramjet model will be considered for which generated output values will be compared with those from a commercial program GASTURB 9 iterated under the same input parameters. Several governing thermodynamic equations will first be discussed in order that we understand the fundamental idea behind values printed out on the GUI. C++ compiler was chosen as a tool of use due to its availability, ease of use, ability to compute functions faster and uniquely possible to make a stand alone GUI executable in DOS mode. The program is developed in such a way that given the ambient flight conditions, burner exit temperature and several geometry areas the program generates its own input values used in the succeeding stations. A close resemblance of output values that define performance and thermodynamic state of the engine was realized between GASTURB 9 and using this code made from C++ compiler.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.3
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• pp.108-120
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• 2001

In this paper, the braking performance considering the dynamic weight is analyzed about the tractor-semitrailer vehicle. The basic brake performance, the parking brake performance, the emergency brake performance and the locking point deceleration etc. are to be calculated for the brake system design of the tractor-semitrailer vehicle. This braking performance is related to traffic regulations and braking characteristics according to the vehicle deceleration, the tire-road friction coefficient and specifications of the air brake system. The design program for the braking performance based on various design variables of the vehicle and the air brake system is developed integrating the analysis functions. This design program is developed by an object oriented programming method that is windows based. GUI (Graphic User Interface) function and the convenience of operating are greatly considered.

• Journal of KSNVE
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• v.5 no.3
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• pp.337-344
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• 1995

A BEM program is developed for the performance analysis of axisymmetric mufflers. In the program the sub-region method is used to deal with singularity or inner boundary. The program is applied to typical axisymmjetric mufflers such as simple expansion, extended tube, perforated tube and absorptive expansion sufflers. The transmission losses of the mufflers are calculated by the program and compared with experiments. It is found that the prediction is in a good agreement with measurement, except for the absorptive muffler with parallel lining.