• Bulletin of the Society of Naval Architects of Korea
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• v.31 no.3
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• pp.16-20
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• 1994

본 고에서는 진동관점에서 특히 문제시되고 있는 장행정.소수실린더.저속 2행정 디젤주기관의 기진력 발생기구와 기관본체진동에 대하여 살펴보고, 박용디젤 추진축계의 진동문제와 관련해 서는 1980년 이후부터 본격적으로 시작된 국내의 연구사례들을 중심으로 이 분야에 대한 연구 현황을 소개하고 향후 중심적으로 연구해야 할 문제점들을 검토하고자 한다.

• Agrochemical news magazine
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• v.20 no.2 s.149
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• pp.10-13
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• 1999

• The Magazine of Kiice
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• v.14 no.2
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• pp.43-49
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• 2013

• Transactions of the Korean Society of Automotive Engineers
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• v.3 no.2
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• pp.130-135
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• 1995

In this paper, the numerical simulation of the method of characteristics for a two-stroke SI engine was carried out, and the scavenging efficiency and the performance of single engine with two types of exhaust system, that is, a pipe exhaust system and a tuned exhaust system, were predicted and compared. The conculusions are obtained as follows. (1) The method of characteristics of hometropic flow considering the friction and the variation of area is useful to predict the scavenging efficiency and the performance of the two-stroke engine. (2) The shape of exhaust system effects directly on the scavenging and the trapping efficiency. (3) A tuned exhaust system consisted of the diffuser and the convergent nozzle makes the plugging pulse and therefore enhances the scavenging and the trapping efficiency. (4) It may be possible to design the optimum exhaust system by using the plugging pulse.

• Bulletin of the Society of Naval Architects of Korea
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• v.39 no.4
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• pp.70-96
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• 2002

• Proceedings of the Korean Association of Geographic Inforamtion Studies Conference
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• 2008.06a
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• pp.189-194
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• 2008

국가지리정보체계의구축및활용등에관한 법률(이하 NGIS법)에 따라 국가GIS의 효과적인 구축 관리 및 활용을 위하여 기본지리정보가 구축되고 있다. 기본지리정보는 국가공간정보기반으로서 기본이 되는 데이터이며, 법적 근거에 따라 중첩활용이 가능해야 한다. 따라서 본 논문에서는 기본지리정보 중첩활용성 제고를 위하여 지리정보 중첩활용에 대한 수요를 조사 및 분석하였다. 설문 응답자는 민간기업이 38.2%로 가장 많았으며, 교육기관, 정부투자기관, 연구기관, 중앙행정기관, 지방자치단체의 순으로 조사되었다. 기본지리정보 활용목적은 기술관련 업무용으로 가장 많이 사용하였으며, 연구관련 업무용, 부가가치생산용의 순으로 나타났다. 기본지리정보 활용 우선순위는 교통분야가 가장 높았으며, 지적분야, 공간영상분야, 지형분야의 순으로 나타났다. 기본지리정보 상호간 중첩활용수요는 교통분야가 가장 높고, 지적분야, 공간영상분야, 지형분야의 순으로 나타났다. 기본지리정보 상호간 중첩활용 수요에 있어서도 '교통-시설물' 중첩활용수요가 가장 높았으며, '행정구역-교통', '행정구역-지적', '행정구역-시설물' 등의 순으로 나타났다. 기본지리정보 중첩활용을 위한 요구사항을 1순위부터 5순위까지 조사한 후 가중치를 부여하여 합산한 결과 데이터품질이 가장 높았으며, 데이터포맷, 데이터모델, 데이터구축지침, 데이터생산사양의 순으로 나타났다. 이러한 수요조사 결과를 기반으로 향후 기본지리정보 중첩활용성을 제고하기 위한 시범구축 등을 수행하여 사용자의 수요를 만족시킬 수 있는 상호호환성이 확보된 기본지리정보의 공급이 요구된다.

• Journal of Advanced Marine Engineering and Technology
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• v.34 no.1
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• pp.62-68
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• 2010

The requirement of high efficiency and low emission for marine diesel engines are being enforced because of air pollution and climate change on the earth. In connection with these, many new technologies are considered. But they are mainly for new building ship. It is necessary to be concerned about the improvement of engine performance for existing ship. In this paper, the simulation program for performance of marine two-stroke diesel engine was developed to predict the deteriorating performance according to elapsed time for existing ship. The result was compared with the result of the program named TOP-CODE which was used by engine maker and checked to be shown good agreement between them.

• Health Policy and Management
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• v.34 no.1
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• pp.48-58
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• 2024

Background: The purpose of this study was to investigate the association between external medical service use and the characteristics of Chungcheongnam-do patients. We aimed to provide evidence of external medical service use enhance the healthcare delivery system in Chungcheongnam-do. Methods: We used the Health Insurance Cohort DB 2.0 of 2016-2019, and 2,570,439 patients were included in the study. Multivariate logistic regression and multinomial logistic regression were used to identify the association between external medical service use and each patient characteristic. Generalized linear model was used to identify the association between medical costs and external medical service use area. Results: During the study period, 32.2% of inpatients and 12.5% of outpatients had external medical service use in Chungcheongnam-do. In comparison to patients living in Cheonan and Asan, the odds ratio (OR) for external medical services use was higher across all regions. Specifically, hospitalized patients from Gyeryong, Nonsan, and Geumsan (OR, 116.817) and Gongju, Buyeo, and Cheongyang (OR, 72.931) demonstrated extremely high likelihood of external medical service use in the Daejeon area. Furthermore, compared to medical expenses incurred within Chungcheongnam-do, patients with external medical service use in the capitol area (outpatient=17.01%, inpatients=22.11%) and Daejeon area (outpatient=16.63%, inpatients=15.41%) spent more on healthcare services. Conclusion: This study found the evidence of external medical service use among Chungcheongnam-do patients. Further study should be conducted taking into account variables including satisfaction of local medical services, different types of patient diseases, and others. The study's findings may serve as a foundation for policy proposals aimed at ensuring the financial stability of our health insurance system, ensuring the efficient delivery of medical care, and localization of medical care.

• Water for future
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• v.43 no.2
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• pp.44-50
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• 2010

• 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.