• 연구논문집
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• s.28
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• pp.49-58
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• 1998

In order to analyse the scavenging efficiency in a poppet valve type 2-stroke engine. visualization of scavenging flow and quantitative experiments for measuring scavenging efficiency were performed. The effect of shroud angle in RSSV which was developed by KIMM was evaluated under steady flow rig applying single-cycle method. Also dynamic simulator was used by using gas sampling with $CO_2$ and $O_2$gas. The $90^circ$ shroud RSSV was found to be the highest efficient system, and single-cycle and dynamic simulator test are very effective to save time and cost for the development of a 2-stroke engine.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.1
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• pp.57-63
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• 2007

The oxidizer-rich preburner is applied to the high efficiency closed cycle rocket propulsion system. This system is generally operated on oxidizer-fuel mixture ratio over than 50. The spray quality and mixing performance are very important for stable combustion of this preburner. This paper presents basic design concept and spray characteristic of the oxidizer-rich preburner injector and this result could be applied to the development of the oxidizer rich preburner system.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2006.11a
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• pp.47-53
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• 2006

The oxidizer-rich preburner is applied to the high efficiency closed cycle rocket propulsion system. This system is generally operated on oxidizer-fuel mixture ratio over than 50. The spray quality and mixing performance are very important for safe combustion of this preburner. This paper presents basic concept and spray characteristic of the preburner injector.

• Proceedings of the Korea Association of Information Systems Conference
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• 2004.11a
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• pp.489-498
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• 2004

• Journal of the KSME
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• v.17 no.3
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• pp.183-192
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• 1977

우리 나라에서의 NC 공작기계에 관한 현황을 보면 약 100대의 각종 NC 공작기계가 수입되어 사 용되고 있다. NC 공작기계의 국산화는 KIST에서 최초로 시도되었는데 그 개발결과 성능면에서 호평을 받게 되었다. 기계를 국산화함에 있어서 그 구성부품들을 정밀가공하는 것도 중요하지만 그 보다 더 중요한 것은 완성된 기계시스템이 기능면에서 소기의 목적을 달성하는 것이라고 본다 . 본 개발연구에서는 이 점을 중요시하여 Systematic 한 해석과 그에 따른 구성부품의 선택및 제작에 신중을 기하여 소기의 NC 선반을 국산화하였는데 이 과정에서 고려가 되었던 기술적인 제문제와 그에대한 대책등을 소개하기로 한다.

• Korean Journal of Agricultural and Forest Meteorology
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• v.23 no.4
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• pp.268-279
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• 2021

The geospatial schemes based on topo-climatology have been developed to produce digital climate maps at a site-specific scale. Their development processes are reviewed here to derive the needs for new schemes in the future. Agricultural and forestry villages in Korea are characterized by complexity and diversity in topography, which results in considerably large spatial variations in weather and climate over a small area. Hence, the data collected at a mesoscale through the Automated Synoptic Observing System (ASOS) operated by the Korea Meteorological Administration (KMA) are of limited use. The geospatial schemes have been developed to estimate climate conditions at a local scale, e.g., 30 m, lowering the barriers to deal with the processes associated with production in agricultural and forestry industries. Rapid enhancement of computing technologies allows for near real-time production of climate information at a high-resolution even in small catchment areas and the application to future climate change scenarios. Recent establishment of the early warning service for agricultural weather disasters can provide growth progress and disaster forecasts for cultivated crops on a farm basis. The early warning system is being expanded worldwide, requiring further advancement in geospatial schemes and digital climate mapping.

• Journal of Hydrogen and New Energy
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• v.19 no.2
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• pp.139-144
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• 2008

The focus of this research is that the scavenging aspect of in-cylinder is visualized by the PIV method and its characteristic is analyzed so that the scavenging performance of the free piston hydrogen fueled engine can improve with loop scavenging. As the results, the piston of convex type shows the best scavenging performance among the presented pistons. In case of the abnormal expansion, the scavenging of area between cylinder head and cylinder wall doesn't operate well.

• Review of KIISC
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• v.15 no.1
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• pp.17-22
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• 2005

웜, 바이러스, 해킹 등 아직 일어나지 않은 사이버 위협을 예측하여 소기 예·경보를 통해 능동적으로 방어할 수 있는 위협관리시스템(TMS; Threat Management System)이 보안업계의 새로운 관심분야로 떠오르고 있다. 본 논문에서는 이 위협관리시스템의 개념과 기능에 대해 선명하고, 이를 통한 조기 경보의 방법을 논의하고자 한다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.108-111
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• 2017

High performance upper stage engine is necessary for space launch vehicles of geostationary orbit, and staged combustion cycle engine is suitable due to high specific impulse. Technology demonstration model for 9 tonf class staged combustion cycle engine, which is consisted of turbopump, preburner, combustion chamber and supply system, was assembled, and hot-firing test was conducted for three seconds in Upper-stage Engine Test Facility of Naro Space Center. Ignition, combustion and shut down of engine system was performed normally, and its performance parameters were evaluated.

• The Journal of Information Technology and Database
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• v.1 no.2
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• pp.53-70
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• 1994

정보시스템 계획수립은 정보시스템 분야의 가장 주된 관심사이다. 최근에 들어 국내에서도 정보기술의 급격한 발전과 업무활동의 통합 필요성에 따라 이에 대한 관심이 매우 높아지고 있다. 실제로 정보시스템 계획수립에는 많은 자원이 소요되고, 이를 올바르게 수행하여 소기의 효과를 거둔다는 것은 쉽지 않은 일로 여겨지고 있다. 본 연구는 정보시스템 계획수립상 겪는 문제점을 토대로 문제점간의 인과관계모형을 제시한다. 이 인과모형은 국내 정보시스템 계획수립상의 문제점을 체계적, 근원적으로 해결하는 방안의 마련에 활용될 수 있을 것이다.