• 한국음향학회지
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• 제20권1호
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• pp.21-29
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• 2001

실제 해양에서 선배열 센서에 수신되는 표적신호의 좌·우 구분된 도래방위를 정확히 예측하기 위해 역빔형성 (Inverse beamforming) 알고리즘을 도입하여 이론적 고찰 및 모사에 의한 방위탐지 성능분석을 수행하고, 고전적인 좌우분리 빔형성 (Cardioid beamforming) 기법에 역빔형성 알고리즘을 적용한 좌우분리 역빔형성 기법을 고안하여 성능분석을 수행하였다. 이상적인 조건하에서 선배열 역빔형성기는 고전 빔형성기에 비해 배열이득이 3dB 이상 향상되고, 빔폭도 고전빔형성기에 의한 빔폭의 0.68배 정도로 성능이 향상됨을 입증하였다. 좌우분리 역빔형성 기법은 고전 알고리즘에 의한 탐지성능에 비해 탐지의 정확도, 분해능의 탐지성능이 우세함을 모사에 의해 입증하였고, 특히, 표적 기동시 센서 축방향에 대한 탐지성능이 고전 알고리즘에 비해 우수함을 입증하였다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.75-78
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• 2004

Various jet engines (Turbine engine family and RAM Jet engine) have been developed for high speed aircrafts. but their application to hypersonic flight is restricted by principle problems such as increase of total pressure loss and thermal stress. Therefore, the development of next generation propulsion system for hypersonic aircraft is a very important subject in the aerospace engineering field, SCRAM Jet engine based on a key technology, Supersonic Combustion. is supposed as the best choice for the hypersonic flight. Since Supersonic Combustion requires both rapid ignition and stable flame holding within supersonic air stream, much attention have to be given on the mixing state between air stream and fuel flow. However. the wider diffusion of fuel is expected with less total pressure loss in the supersonic air stream. So. in this study the direction of fuel injection is inclined 30 degree to downstream and the total pressure of jet is controlled for lower penetration height than thickness of boundary layer. Under these flow configuration both streams, fuel and supersonic air stream, would not mix enough. To spread fuel wider into supersonic air an aerodynamic force, baroclinic torque, is adopted. Baroclinic torque is generated by a spatial misalignment between pressure gradient (shock wave plane) and density gradient (mixing layer). A wedge is installed in downstream of injector orifice to induce an oblique shock. The schlieren optical visualization from side transparent wall and the total pressure measurement at exit cross section of combustor estimate how mixing is enhanced by the incidence of shock wave into supersonic boundary layer composed by fuel and air. In this study non-combustionable helium gas is injected with total pressure 0.66㎫ instead of flammable fuel to clarify mixing process. Mach number 1.8. total pressure O.5㎫, total temperature 288K are set up for supersonic air stream.

• 한국컴퓨터정보학회논문지
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• 제16권3호
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• pp.27-34
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• 2011

본 논문에서는 영상의 명암대비(contrast)를 개선시키는 언샾 마스킹 방법을 제안한다. 언샾 마스킹은 이미지가 가지고 있는 에지와 디테일 정보를 개선시키는데 일반적인 샤프닝 마스크 보다 효과적이기에 이에 관한 많은 연구가 있었다. 제안하는 방법은 방향성 정보를 이용한 블록 단위의 언샾 마스킹 방법으로 영상을 블록 단위로 분할하고 DCT(Discrete Cosine Transform)를 이용하여 각 블록에서 패턴의 방향성 정보를 얻어낸다. DCT 결과로부터 해당 블록들의 방향성 타입을 결정하고 이에 따라 언샾 마스크를 적응적으로 적용한다. 블록의 분류는 평탄영역, 텍스처, 에지 그리고 나머지 형태로 구분되어 진다. 평탄 영역에 속하는 블록은 잡음에 의한 영향을 줄이기 위해 언샾 마스킹을 적용하지 않으며 텍스처와 에지영역에 대해서는 고주파 성분을 강조하기 위해 블록타입에 맞는 적응적 언샾 마스킹을 적용한다. 실험을 통하여 영상에서 평탄 영역은 잡음에 의한 훼손을 줄이며 에지들이 포함된 텍스처 영역은 적응적으로 강조하여 시각적으로 우수한 명암대비 개선 결과를 얻을 수 있었다.

• 한국측량학회지
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• 제21권4호
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• pp.347-353
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• 2003

최근 수치사진측량은 각종 첨단 산업분야에 그 응용이 증대되고 있으며, 많은 관심과 연구가 진행되고 있는 실정이다. 따라서 본 연구에서는 수치사진측량에 의한 도로평면선형정보체계 개발하였다 먼저 수치사진측량에서 취득된 자료들을 객체 지향적인 언어인 Delphi를 이용하여 도로평면선형정보(BC,EC,R,IP)를 구축하는 프로그램을 개발하였고, 개발된 프로그램은 영상자료를 많이 이용하여 기존보다 시각적인 효과를 극대화할 수 있었다. 그리고 개발한 도로평면선형정보의 제원 값은 동적GPS에 의해 취득된 자료를 최소제곱법의 원리를 이용한 평면선형추출 프로그램값과 비교하면, IP값은 약 X,Y방향으로 약 2m정도 정확도가 향상되었고, 곡선반경(R)은 약 2.5m정도의 정확도향상이 있었다.

• 한국해양바이오학회지
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• 제6권2호
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• pp.84-101
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• 2014

The aim of this project is to develop an adaptive and collective National Marine Biotechnology Plan for the next decade(2014~2023) which is able to reflect current and future changing environment. This effective strategy targets to foster marine-derived active bio-materials, marine bioenergy production technology and many promising technologies in order to promote marine biotechnology industry as a next-generation growth engine. Marine biotechnology industry based on R&D activities since 1980 has been growing as an emerging industry. This new field enables to secure exclusive patent rights and to find new potential bio-active materials from the ocean that requires long-term aggressive R&D investments. The current policy direction is to raise appropriate level of R&D investment because the current Korea's national marine biotechnology R&D fund ratio is less than 2% of the total national biotechnology R&D budget. The result shows three major strategies. First, it recommended a research implementation system and supporting policy that includes establishment of open innovation framework for the 'Industry-Academia-Research Institute Collaborations', strategic research planning and enhanced policy making process. Second, it derived state-of-the-art or new technology in many areas. Third, it formulated more detailed execution plans for successful R&D support and set up performance indicator system in related R&D program.

• 한국융합학회논문지
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• 제8권4호
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• pp.19-24
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• 2017

본 연구는 최근 전자 금융거래의 증가와 동시에 금융거래 정보의 탈취 혹은 변조 등 보안위협 또한 급증하면서 안전한 보안 방안과 대응이 시급한 실정이다. 이에 종래에 사용된 사기방지시스템 혹은 이상금융거래 탐지시스템(FDS, Fraud Detection System, 이하 FDS)을 최근 주목 받고 있는 빅데이터 관련 기술(이상금융거래에 대한 다양한 형태의 정형/비정형 금융거래 이벤트 데이터를 실시간으로 수집/저장하고 과학적 연관 분석 기법을 활용하여 비정상 행위를 탐지 및 차단할 수 있는 기능)을 활용하여 국내 금융회사인 A사에 개선 모델을 구축 하였다. 구축결과 시나리오 고도화 분석을 통한 오검출을 최소화 하여 기존 시나리오 Detect탐지 대상의 감소 효과를 나타냈다. 아울러 FDS고도화에 대한 향후 발전방향을 제안하고자 한다.

• 한국통신학회논문지
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• 제30권6B호
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• pp.377-386
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• 2005

최근 들어, 실시간 디스크 스케줄링에서 단위 시간당 처리량을 최대화하기 위한 다양한 실시간 스케줄링 알고리즘들이 연구되고 있다. 특히, 실시간 디스크 스케줄링 알고리즘을 대표하는 EDF(Earliest Deadline First)에 스캔기법을 적용한 많은 알고리즘들이 연구되고 있다. 그러나 제안된 디스크 스케줄링 알고리즘들은 스캔 그룹을 생성할 때 계속되는 I/O 요구들을 고려해야 하기 때문에 많은 제약을 가지고 있다. 또한, 스캔 기법에서 서비스 방향의 고정으로 인하여 디스크의 효율성을 떨어뜨리는 결과를 초래하고 있다. 본 논문에서는 기존의 경성 실시간 시스템에서 사용되는 실시간 디스크 스케줄링 알고리즘들의 문제점을 해결하기 위해 삽입 기법과, 양방향 스캔기법을 기반으로 한 새로운 실시간 디스크 스케줄링 알고리즘을 제안하고 실험을 통해 제안 시스템의 시간당 처리량과 서비스 가능한 I/O 요구가 우수함을 증명한다.

• 한국IT서비스학회지
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• 제16권1호
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• pp.139-162
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• 2017

Museums contain a significant meaning as a place that reflects empirical knowledge that have been accumulated socially and scientifically in overall life of the public and provides the opportunity to enjoy prestigious culture, while serving as the extended place of education. The first objective of this study is to increase the accessibility of general public through the development of online museum programs as service contents and to present the ultimate direction the development of in art appreciation contents that can effectively expand the infrastructure of culture and art. Second, the effectiveness of online art appreciation programs by registered private museums, which continuously develop smart media-based online museum contents and systemization of archive as the distribution rate of smart devices is increased due to generalization of digital environments, was analyzed by each case to examine the objective distinctions strategies. Third, in terms of museum visitors and smart contents users, this study examines the expected effects of popular distribution by seeking various ways that can enhance the desired exhibit appreciation and autonomous utilization of educational programs, while not being restricted by the physical accessibility and limitation of space at the museums. The subjects of this study included cases of BoroomSan Museum, Savina Museum of Contemporary Art, Imageroot, Sangwon Museum of Art, Hello Museum, etc. and the online smarts contents art appreciation educational programs by registered private museums were analyzed. Results expected to achieve from such processes are as follows. First, the possibility to expand cultural participation in museum exhibition appreciation and museum education infrastructure became widen. Second, the educational program resources can be utilized as the culture and art asset that strengthens the museums' responsibilities in their social role. Third, museum archive can be constructed in more systematic way, and the efficiency of museum archive system can be enhanced to maintain the museum collection database in a consistent format. Fourth, the museum's smart contents users' continued access to museum's online contents may induce the exhibition effect of the site and voluntary participation in education, and can also expect an economic synergy effect as the users become potential visitors that may actually visit the museum in the future.

• E2M - 전기 전자와 첨단 소재
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• 제9권1호
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• pp.18-23
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• 1996

The molding pressure is also one of the important parameters in the preparation of HTSC materials by the solid state reaction method. In the present study, changes in structural, electrical and microstructural proper-ties with the molding pressure in YiB $a_{2}$C $u_{3}$ $O_{70{\delta}}$ superconductors have been performed. The investigated molding pressures were 0.5*10$^{3}$ N/c $m^{2}$, 1*10$^{3}$ N/c $m^{2}$, 2*10$^{3}$ n/c $m^{2}$ and 4*10$^{3}$ N/c $m^{2}$. As the molding pressure increased, the anisotropy of the crystal structure decreased and the grains have been grown preferentially in a c-axis direction. Since the size of the grain becomes larger with the decrease of the porosity, denser textures are formed. The results indicated that the critical current density is improved resulting from the enhanced densification due to higher molding pressure. When the molding pressure was between 1*10$^{3}$ N/c $m^{2}$ and 2*10$^{3}$ N/c $m^{2}$, while it did not affect the oxygen deficiency and Tc, the increase of the molding pressure affects remarkably on grain size and densification of the $Y_{1}$B $a_{2}$C $u_{3}$ $O_{7-{\delta}}$. When the molding pressure is larger than 2*10$^{3}$ N/c $m^{2}$, electrical proper-ties are independent on the molding pressure..

• 한국의류학회지
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• 제40권6호
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• pp.1062-1071
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• 2016

Olympic uniforms emphasize aesthetics along with sports fashion trends and tendencies to display national competitiveness through colorful designs that use the national flag or colors as motifs. Korea needs to enhance the national brand through international sporting events such as the 2018 PyeongChang Olympic Games (30 years after the 1988 Seoul Olympic Games); therefore, a multilateral analysis is required to promote a global image of Korea. This study presents a development direction for more diverse national brand values for Korea through design research on Olympic uniforms. Research methods investigated the concepts and changes of the Geongongamli, and Taegeuk symbols as well as Olympic uniforms based on literature data and existing studies using uniforms. An Olympic uniform using symbols of the Korean flag was designed through a case analysis of Olympic uniform designs of countries that participated in the 2012 London Summer Olympic Games and 2014 Sochi Winter Olympic Games that reflect the countries' image. The research scope excluded uniforms for the actual games and limited the uniforms to official uniforms for the opening ceremony that represent the characteristics of each country; consequently, we analyzed 70 uniforms of 162 countries of the Winter Olympic Games. As a result, official national symbols were more frequently reflected than unofficial symbols in the uniform designs of the Summer and Winter Olympic Games with more frequencies of direct reflection than indirect reflection. Korea's national brand is expected to enhanced through a uniform that expresses Korea's image at international events and global exchanges.