• Journal of the Korean Society of Propulsion Engineers
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• v.15 no.5
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• pp.19-26
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• 2011

In order to investigate the effect of fuel injection hole configuration within the scramjet combustor, experiment and quasi-one-dimensional analysis was performed. And the results were compared with experiment and analysis result which were performed in 2008 with same facility and test condition. Fuel injection hole size was decreased and quantity was increased. However the depth of fuel penetration and flow quantity of fuel were maintained. As a test result, combustion performance was increased significantly with no-cavity injector and slightly with plain-cavity. However, combustion performance with zigzag-cavity was decreased.

• Journal of the Society of Naval Architects of Korea
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• v.52 no.3
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• pp.206-221
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• 2015

Supercavitation is a modern technique which can be used to surround an underwater vehicle with a bubble in order to reduce the resistance of the vehicle. When the vehicle is at low speed in the deep sea, the cavitation number is relatively big and it is difficult to generate a cavity large enough to envelope the vehicle. In this condition, the artificial cavity, called ventilated cavity, can be used to solve this problem by supplying gas into the cavity and can maintain supercavitating condition. In this paper, a relationship between the ventilation gas supply rate and the cavity shape is determined. Based on the relationship a ventilation rate control is developed to maintain the supercavitating state. The performance of the ventilation control is verified with a depth change control. In addition, dynamics modeling for the supercavitating vehicle is performed by defining forces and moments acting on the vehicle body in contact with water. Simulation results show that the ventilation control can maintain the supercavity of an underwater vehicle at low speed in the deep sea.

• Journal of the Society of Naval Architects of Korea
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• v.53 no.3
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• pp.201-209
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• 2016

Supercavitation is a technology that reduces frictional resistance of an underwater vehicle by surrounding it with bubbles. Supercavity is divided into natural supercavity and ventilated supercavity which is formed by artificially supplying gas. Planing forces are present when a section of the underwater vehicle goes outside of the cavitation region in the supercavity condition. Planing often leads to an unstable flight because it acts vertically on the body suddenly. In this paper, a relationship between the ventilation rate and the cavitation number is determined. Based on the relationship, desired cavitation number which can avoid to planing is determined and then ventilation controller is designed. The performance of the ventilation controller is verified with a depth change controller using the cavitator. Simulation results show that the ventilation controller can minimize the planing force and moment.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.11a
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• pp.423-431
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• 2010

In order to investigate the effect of fuel injection hole configuration within the scramjet combustor, experiment and quasi-one-dimensional analysis was performed. And the results were compared with experiment and analysis result which were performed in 2008 with same facility and test condition. Fuel injection hole size was decreased and quantity was increased. However the depth of fuel penetration and fuel flow were maintained. As a test result, combustion performance was increased significantly with no-cavity injector and slightly with plain-cavity. However, combustion performance with zigzag-cavity was decreased.

• Journal of the Korean Institute of Rural Architecture
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• v.10 no.1
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• pp.51-58
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• 2008

This study examined the present condition and problems of rural apartment house through documentary survey and considered the social necessity and concept of rural apartment housing. The aim of this study is to suggest the social necessity and spatial composition factor of rural apartment housing. The results of this study are as follows. First, rural apartment houses are generally adjacent to production and natural environments, and tend to be constructed in small complex of 50 households or less with the lack of convenient facilities. Second, the ultimate goal of rural apartment housing plans is to improve the livability, community, sustainability and rurality on the basis of the basic direction of rural areas. Third, it is necessary to install storages within the apt. complex and secure a buffer zone where people can wash their hands before entering the houses. Fourth, rural apartment housing should adopt the space components of auxiliary facilities including storages for agricultural products and farming appliances, common workshops, field attached to home, and washrooms in consideration of the conditions of rural areas different from urban apartment housing.

• Journal of the Korea Society of Computer and Information
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• v.26 no.2
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• pp.157-167
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• 2021

This research strives to find the effective Local Currency Model that considered regional characteristics of Innovation city. Currently, the issuance of the domestic local currency has been increased due to COVID-19 Pandemic, yet most regions operate it in the same way without consideration of the characteristics and environment for each region, which leads to a lack of motivation for local communities to continue to participate. The regional characteristics of innovative cities were analyzed in order of policy characteristics of innovation cities, population growth issues, settlement and consumption environment. The new local currency model was proposed for innovation cities based on a private blockchain system with the participation of public institutions to solve and supplement regional issues.

• Proceedings of the Korean Information Science Society Conference
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• 2001.10b
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• pp.235-237
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• 2001

본 논문에서는 수평형 프로젝션 시스템인 상호작용형 워크벤치와 수직형 프로젝션 시스템인 프로젝션 월을 기반으로 하는 반몰입 가상환경을 구축하고 이를 기반으로 사용자의 시점에 따라 변하는 건물 모델을 입체적으로 가시화 하는 방법을 제시한다. 상호작용형 워크벤치는 일반적인 수직 디스플레이와 달리 수평면/경사면 디스플레이가 가능하고, 프로젝션 월은 널은 디스플레이 환경을 제공하므로 소규모의 공동작업에 용이하며 두 시스템 모두 반몰입감을 제공한다는 장점이 있다. 본 논문에서는 이러한 환경에서 주사용자의 위치와 시점 변화에 따라 달라지는 건물 모델을 실제 배경 영상과 합성한 결과를 제시한다.

• The Korean Journal of Archival Studies
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• no.38
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• pp.225-264
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• 2013

The Purpose of this study is to analyze an active discussion in North America about the issue of community archives governance which mainly focused on 'participatory archives' model and from it, draws implications for the present stage of domestic community archives development. Traditionally in the United States and Canada, local community archives have been built mostly by mainstream cultural institutions such as public archives, public libraries, museums, and historical societies as a part of comprehensive documentation of the society at large. At the same time, they have been processed and managed in accordance with the institution's collection development policy. As a result, most community archives in North America are characterized as top-down community archives model (in contrast with down-up model of 'independent' community archives as a part of grass roots movement in the UK). Recently, the community archives in North America with these characteristics try to overcome their limitations, which result in 'the others' of community archives, through governance, that is, community-institution partnership. Participatory archives model which assumes active community participation in all archives processes is being suggested by archival communities as the effective alternative of governance model of top-down community archives. This discussion of community archives governance suggests progressive direction for the present stage of domestic community archives, which has been built mostly by various mainstream cultural institutions and still has been stayed in 'about the community' stage. Particularly, community outreach strategies that participatory archives model concretely suggests are useful as a conceptual framework in building community archives based on community-institution partnership in reality.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.151.1-151.1
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• 2010

우리나라의 신재생에너지 기술개발은 2008년 '저탄소 녹색성장' 국가 비전 선포 이후 국가 에너지 R&D 전략의 중심에 자리 잡고 있다. 이미 우리의 경쟁 대상인 선진국들은 신재생에너지 기술을 중심축으로 녹색산업을 신성장 동력으로 활용하고자 국력을 집중하고 있다. 우리나라는 선진국과 비교할 때 상대적으로 신재생에너지 기술개발 후발자이다. 기술적 핸디캡을 극복하고 대등한 경쟁에 뛰어들기 위해서는 신재생에너지 기술보유 선진국과의 국제협력을 통한 시너지효과 창출이 필요하다. 이는 최고수준의 국가 및 기관들과 협력을 도모함으로써 기술개발 기간 단축은 물론 조기 기술격차 해소가 가능하기 때문이다. 이러한 국가간 상호협력을 위해서는 무엇보다 기술 분야별 선진국 수준과 우리의 수준에 대한 객관적인 분석이 필요하다. 이를 위해 주요 신재생에너지 기술들을 대상으로 심층적인 전문가 조사를 통해 전세계 주요 국가 및 관련 업체들의 기술수준 및 협력 선호 유형을 분석하였다. 이에 더해 관련 기술 시장 상황을 고려하여 기술별 국제 협력 추진 전략을 시장주도형 모델과 공동연구형 모델로 나누어 수립하였다. 수립된 전략을 바탕으로 신재생에너지 기술 국제협력 활성화를 위한 정책 추진 방향을 제시하였다.

• Proceedings of the Fisheries Business Administration Society of Korea Conference
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• 2005.11a
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• pp.29-50
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• 2005

EU는 세계 3위의 어업생산지역임에도 불구하고 가공어류와 양식수산물에 대한 세계 최대의 소비시장을 가진 탓에 만성적인 수산물 공급부족을 겪고 있다. 이에 따라 EU는 일찍부터 제3국과의 어업협정을 통한 원양어장 진출을 적극적으로 추진해 왔다. EU의 원양어장 진출정책을 시기별로 분류하면 1세대 유형에서부터 4세대 유형으로 구분가능하다. 수역별로는 크게 유럽북부와 남부수역으로 분리되어 있으나, 어업협정 유형으로는 북유럽형, 발틱형, 북미형, 중남미형, 그리고 ACP형으로 세분화 할 수 있다. EU는 특히 대부분의 쌍무어업협정을 아프리카, 인도양, 서태평양 연안국들과 맺고 있어, 이들 국가와의 쌍무적 어업관계가 EU 원양어업정책에 있어 매우 중요하다. 최근 원양어장의 자원부족현상이 점차 심각해짐에 따라 EU 위원회는 그들의 공동어업정책 개혁안에 제3국과의 어업협력강화 방안을 수립하였다. 이는 연안국과의 어업관계를 단순입어에서 동반자적 입어관계로 발전시키는 한편, 어업 외적인 부문의 협력을 포함하는 포괄적 접근 정책을 추진하고 있다. 이러한 EU의 움직임은 단순한 어획쿼터할당에 대한 입어료지급 방식은 조업국과 연안국 간의 신뢰관계 증진에 그다지 도움이 되지 못한다는 것을 의미한다. 따라서 조업국은 연안국에 대한 자원관리기술을 지원해 주고, 자원평가에도 공동으로 참여함으로써 양국간 협력적 수산자원관리정책을 지향하도록 하여야 한다는 것을 시사하고 있다.