• Journal of the Korean hospital association
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• v.17 no.6 s.155
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• pp.8-11
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• 1988

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2008.11a
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• pp.149-152
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• 2008

A slinger combustor which can be applied to micro turbojet engine has been developed with the combustor rig test. A rotating fuel injector with high speed rpm was designed, manufactured and tested to apply into slinger combustor through spray test and adequate droplet size and spray distribution were achieved. The CFD was used to analyze internal flow of the combustor. We found out that the combustor shows 11.2% of pressure loss and 99.8% of combustion efficiency at full combustor rig test.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2005.11a
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• pp.240-246
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• 2005

A series of combustion tests of a 30-tonf-class full scale liquid rocket thrust chamber under development has been carried out to verify its design. The test results revealed decent performance in the aspects of efficiency. The combustion stability is one of the most important parameters of liquid rocket engine in addition to the efficiency. Assessment tests of combustion stability must be accomplished to confirm the possibility of combustion instability due to spontaneous or external disturbances. The combustion stability rating tests of the full scale thrust chamber with temporary baffles made of stainless steel were carried out utilizing pulse guns to estimate combustion stability characteristics. The tests results show highly stable combustion stability characteristics. The outcome acquired from the present experimental study will be used to design an actively cooled baffle that can survive for the life time operation of the thrust chamber.

• Journal of Advanced Marine Engineering and Technology
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• v.18 no.2
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• pp.104-112
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• 1994

The scavenging efficiency has a great influence on the performance of a diesel engine, especially slow two-stroke diesel engines which are usually used as a marine propulsion power plant. And this is greatly affected by the conditions in the cylinder, scavenging manifold and exhaust manifold during the gas exchange process. There are many factors to affect on the scavenging efficiency and these factors interact each other very complicatedly. Therefore the simulation program of the gas exchange process is very useful to improve and predict the scavenging efficiency, due to the high costs associated with redesign and testing. In this paper, a three-zone scavenging model for two-stroke uniflow engines was developed to link a control-volume-type engine simulation program for performance prediction of long-stroke marine engines. In this model it was attempted to simulate the three different regions perceived to exist inside the cylinder during scavenging, namely the air, mixing and combystion products regions, by modeling each region as a seperate control volume. Finally the scavenging efficiency was compared with three type of scavenging modes, that is, pure displacement, partial mixing and prefect mixing.

• Transactions of the Korean Society of Automotive Engineers
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• v.2 no.5
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• pp.48-57
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• 1994

The specific power output and thermal effeciency of any two-stroke engine are dependent on its scavenging behavior. Among the many factors which influence on the scavenging process, the cylinder head shape is one of the important factor. Hence in this study three different type models of cylinder head shape which are the cylindrical, the spherical and the arbitrary shape are studied to show the effects of the turbulent scavenging process in the cylinder with one inlet port, two side ports and one exhaust port. A modified version of KIVA-II which strip out of or add planes of cells across the mesh above the piston for flow simulation of two-stroke engine is used. The $k-{\varepsilon}$ turbulent model is used. The results show that the flow in a two-stroke engine cylinder of the spherical head shape among the three different type model is a desirable for efficient scavenging.

• KOREAN POULTRY JOURNAL
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• v.11 no.10 s.120
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• pp.114-116
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• 1979

항생물질은 만병통치의 대명사가 아니며 적기적소에 가장 효율적으로 사용함으로 소기의 목적을 얻을 수 있다는 사실을 사양가들과 기술자 들에게 좀더 생각해볼수 있는 기회가 되길 바라며 축산사육경험이 많을수록 질병의 위험을 항생물질에 의존하는 막연한 생각에 도움이 되길 바란다. 우수한 축산물을 생산하기 위하여 우선 내가 선택한 사양관리방법에 돌이켜보고 그 다음 부족한 곳에 항생물질의 원조를 받아서 수익성 높은 축산경영을 기대해야 할 것이다.

• Journal of Advanced Marine Engineering and Technology
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• v.21 no.4
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• pp.421-429
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• 1997

This study is theoretically examined the influences on the performance of diesel engine super¬charged by exhaust gas turbine with the change of excess air factor, admission ratio, total efficien¬cy of turbine and compressor, scavenging pressure ratio, and scavenging temperature. In this study, all calculations are carried out by computer, and the theoretical engine performance is com¬pared with the actual engine performance which is offered from engine manufacturer. Following results are acquired by this study. The mean effective pressure is increased with decrease of excess air factor or increase of scavenging pressure ratio. As the admission ratio or total efficiency of tur¬bine is increased, the mean effective pressure is increased but the specific fuel consumption is decreased. Mean calculation error compared with the actual engine performance is under 5 per¬cents, therefore, this calculation method can be used in the design of diesel engine.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.32 no.3
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• pp.310-315
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• 1996

엔진 배기가스의 동력과 유량이 배기행정의 직전 단계에서 관찰되었다. 배기가스 양을 적당히 조정함으로써 터보 과급의 입구 압력을 증가시킬 수 있었으며 엔진의 흡기, 소기 및 배기과정에서 가스질량과 엔진의 동력, 그리고 터보과급 효과도 감소하였다. 터보 과급장치를 기하학적으로 적절화시킴으로써 싸이클의 동기화 및 동력의 효율이 고려된 열교환 과정의 효율 기준도 제기되었으며 디젤엔진의 연소싸이클을 재수정하는 과정과 터빈의 동역학적 특성도 제시되었다.

• Journal of Korea Society of Industrial Information Systems
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• v.22 no.5
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• pp.65-84
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• 2017

This Study is Empirically Analyzed the Relationship among Personality, Job Satisfaction and Turnover Intention of Marketing Counselor of Mutual aid Fund for Small Enterprises and Small Enterprisers. The Collected 205 Counselors Data were Verified the Cause-and-effect Relationship and Mediated Effects among Variables by Exploratory Factor Analysis, Reliability Analysis, Multiple Regression Analysis. Personality Traits have a Significant Effect on Job Satisfaction and Turnover Intention. Job Satisfaction was Proved to have a Mediating Effect Between Personality Factors and Turnover Intention. In order to Encourage the Counselor to work and to Improve the Effectiveness of System, this Study Suggested the Necessity of Job Satisfaction Improvement Strategy According to Personality Characteristics of Counselor.

• Science & Technology Policy
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• v.2 no.16 s.16
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• pp.21-36
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• 1992

급변하는 국제 기술 환경에서 생존하기 위해서는 미래를 이끌어갈 전략기술을 확보하는 것이 무엇보다 필요하다. 미국,EC,일본 등 각국의 정부는 이를 위해서 국가적 차원에서 연구 개발 사업을 추진하고 있으며 현재 우리 정부가 추진하고 있는 G7 프로젝트도 바로 이러한 시도라고 할 수 있다. 이 국가연구개발사업을 효율적으로 추진하여 소기의 목적을 달성하기 위해서는, 전략 기술들의 발전 전망과 기술 선진국들의 연구 개발동향을 전망하여 우리의 구체적인 목표들을 점검하는 것이 중요하다. 이러한 취지하에 본호에서는 21세기를 선도할 주요 전략기술의 동향과 전망을 살펴보기로 한다. (편집자 주)