• 대한기계학회논문집
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• 제16권12호
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• pp.2349-2357
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• 1992

본 연구에서는 일정한 조도의 거친 평판이 갑자기 매끈한 평판으로 변할 때 (Fig.1 참고) 평판 위에서 발달하는 난류경계층에 관하여 연구하였다. 이때 하류에 서 난류 경계층은 위에서 설명했듯이 완전히 발달한 난류 경계층과는 상당히 다르다. 특히 대부분의 난류 모델은 완전히 발달된 평형상태의 경계층에서의 실험자료를 이용 하여 개발되었기 때문에 이러한 과도 구역에서 합리적으로 적용되기가 어렵다. 과도 구역에서 평균속도와 난류 특성치를 체계적으로 계측하기 위해서는 전단응력을 직접 계측하는 것이 중요하다. 그러나 아직 전단응력을 직접 계측한 연구는 없는 실정이 다. 본 논문에서는 최근에 제안된 CPM(computational preston tube method)를 이용 하여 과도지역에서 전단응력을 직접 측정하여 난류 경계층의 구조를 연구하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2000년도 추계종합학술대회 논문집(4)
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• pp.143-146
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• 2000

In this paper, luminance mapping for uniform color distribution and gamut mapping for maximum chroma reproduction are proposed. In the conventional lightness mapping, the average lightness difference between the two gamut is increased and different color changes in bright and dark regions are also increased. To solve these problems, a lightness mapping is proposed that minimizes the lightness difference of the cusps at each hue angle and produces same color changes in bright and dark regions. Also, chroma mapping that utilize variable anchor point and an anchor point are proposed for maximum chroma reproduction and uniform color change. The proposed algorithm reduce a sudden color change on the gamut boundary of the printer and to maintain a uniform color change during the mapping process. Accordingly, the proposed algorithm can reproduce high quality images with low-cost color devices.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2010년도 추계학술대회
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• pp.175-178
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• 2010

Slow movement of snail can be a benefit since it means less speed of tracking is required to get accurate movement track, but in the other side it is difficult to extract the object because the snail is almost as static as the background. In this paper, we present a technique to track the snail by using one of its common characteristic, dark color of its shell. The technique needs to be robust to illumination change since the experiment is usually to observe the movement of snail both at bright and dim condition. Snail position coordinate in 3D space is calculated using orthogonal stereo vision which combines the information from two images taken from cameras at the top and in front of the aquarium. Experimental results show this technique does not need prior background image extraction and robust to gradual or sudden illumination change.

• 한국자동차공학회논문집
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• 제19권3호
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• pp.16-22
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• 2011

This paper presents the potential of in-vehicle data recorder system for monitoring aggressive driving patterns and providing feedback to drivers on their on road behaviour. This system can detect 10 risky types of drivers' driving patterns such as aggressive lane change, sudden brakes and turns with acceleration etc. Vehicle dynamics simulation and vehicle road test have been performed in order to develop driving pattern recognition algorithms. Recorder systems are installed to 50 buses in a single company. Drivers' driving behaviour are monitored for 1 month. The drivers' risky driving data collected by the system are analyzed. Aggressive lane change in 50km/h below is a cause in overwhelming majority of risky driving pattern.

• Bulletin of the Korean Chemical Society
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• 제19권10호
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• pp.1047-1054
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• 1998

We present the results of molecular dynamics simulations for three different systems of bilayers of long-chain alkyl thiol [S(CH2)15CH3] molecules on an solid-solid interface using the extended collapsed atom model for the chain-molecule. It is found that there exist two possible transitions: a continuous transition characterized by a change in molecular interaction between sites of different chain molecules with increasing area per molecule and a sudden transition from an ordered lattice-like state to a liquid-like state due to the lack of interactions between sites of chain molecules on different surfaces with increasing distance between two solid surfaces. The third system displays a smooth change in probability distribution characterized by the increment of gauche structure in the near-tail part of the chain with increasing area per molecule. The analyses of energetic results and chain conformation results demonstrate the characteristic change of chain structure of each system.

• 복식
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• 제58권8호
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• pp.74-90
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• 2008

Since the late of 20th Century, philosophy, art, and aesthetics have attention to the movement of object that persue the dynamics and qualitative change, not existing fixed and quantitative object. Qualitative continuity, including discontinuity of specific spot and surface that occurs sudden change, is distinct characteristics considered in contemporary logo civilization, which combines and disperses according as various purpose among the different elements and objects. Therefore, I studied about the characteristics of qualitative continuity that creates the change and the differentiation continuously through the "formative characteristics of the continuity expressed in contemporary fashion" of my preceding paper. This paper is the following study of above mentioned paper, and Investigates about aesthetic consciousness leading to the various change. This is intends to consider the trans-aesthetic consciousness that accepts dynamic movement and change the different object and reforms new relationship continuously. This studies' conclusion is as follows; 1) sublimity-Infinity, de-constructive, excessive 2) jouissance - functional, structural 3) paradox-perceptual, spatial. A study about the trans-aesthetic consciousness would help to offer philosophical basis, and make a change building aesthetic foundation in explaining various relationship like as phenomenon of the retro, neo, post, fusion expressed since the late of 20th Century.

• 한국멀티미디어학회논문지
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• 제6권5호
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• pp.797-804
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• 2003

장면 전환검출 (scene change detection)은 영상 정보의 색인 (indexing) 및 검색을 위한 전처리로서 비디오 검색 시스템의 전체 성능을 좌우하는 중요한 기술로 현재 많은 연구가 진행되고 있다. 본 논문에서는 급격한 움직임 및 조명 변화, 빠르게 연속적으로 등장하는 장면 전환에 강건한 급격한 장면 전환 검출 기법과 디졸브, 페이드 등의 장면 전환을 보다 효과적으로 검출할 수 있는 점진적인 장면 전환 검출 기법 및 추출된 셧 (shot)의 내용을 DCT DC 이미지 버퍼링과 누적 히스토그램 교차 함수 (accumulative histogram intersection measure)에 의해 대표 프레임으로 추출하는 새로운 알고리즘을 제안하고, 모의 실험 결과 기존 방식에 비해 보다 우수한 성능을 보임을 입증하였다.

• 한국항해항만학회지
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• 제28권8호
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• pp.759-766
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• 2004

부산은 서울, 대구 등 내륙도시와는 달리 도시화 과정에 수역의 매립이 포함되어 있어 도시화에 의한 도시기후변화에도 매립의 영향이 있을 것으로 생각된다. 이에 본 연구에서는 한국의 3대 도시인 서울, 부산, 대구의 기후변화요인과 70여 년간의 기상데이터를 비교ㆍ분석하여 부산의 기후변화 특성 및 매립과 기후변화의 관련성에 대해 검토하였다. 그 결과 부산에서 매립이 진행되었다는 점을 제외하면 서울, 부산, 대구의 기후변화 요인에는 큰 차이가 없지만 서울, 대구의 경우는 도시화가 진행됨에 따라 최저기온의 연평균 상승이 현저한 것에 비해 부산은 매립이 진행된 시기에 최고기온의 연평균 상승이 현저함을 밝혔다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1997년도 한국자동제어학술회의논문집; 한국전력공사 서울연수원; 17-18 Oct. 1997
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• pp.454-457
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• 1997

As in most industrial processes, the dynamic characteristics of an electric power system are subject to changes. Amongst those effects which cause the system to be uncertain, faults on transmission lines are considered. For the stabilization of the power system, we present an indirect adaptive control method, which is capable of tracking a sudden change in the effective reactance of a transmission line. As the plant dynamics are nonlinear, an input-output feedback linearization method equipped with nonlinear damping terms is combined with an identification algorithm which estimates the effect of a fault. The stability of the resulting adaptive nonlinear system is investigated.

• 항공우주시스템공학회지
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• 제6권4호
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• pp.18-23
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• 2012

The fuel boost pump for the aircraft was first indigenously developed in Korea. It is one of the core component for fuel subsystem and composed of motor assembly, impeller assembly, and body assembly with BLDC motor. It shall provide some amount of fuel to engine system continuously for any flight condition considering sudden altitude change and any attitude. This paper describes the procedures and the results for the design, the integration, and the performance analysis of the fuel boost pump.