• 설비공학논문집
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• 제15권4호
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• pp.274-286
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• 2003

Numerical simulations are performed to investigate the turbulent convective heat transfer of the supercritical carbon dioxide flows in vertical and horizontal square ducts. The gas cooling process at the supercritical state experiences a sudden change in thermodynamic and transport properties. This results in the extraordinary variations of the heat transfer coefficients in the supercritical state, which are much different from those of single or two phase flows. Algebraic second moment closure which can include the effects of large thermophysical property variations of carbon dioxide and of buoyancy is employed to model the Reynolds stresses and turbulent heat fluxes in the governing equations. The previous correlations for the turbulent heat transfer coefficient for the supercritical carbon dioxide flows couldn't reflect the buoyancy effect. The present results are used to establish a new heat transfer coefficient correlation including the effects of large thermophysical property variation and buoyancy on in-duct cooling process of supercritical carbon dioxide.

• 전자공학회논문지D
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• 제35D권3호
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• pp.63-69
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• 1998

In this paper, a new input method is proposed to improve shift-invariant property of a photorefractive correlator andwe implemented real-time optical pattern recognition system using it. In the conventional photorefractive correlator, it is vrey difficult to satisfy the Bragg condition in the pattern recognition process. So, correlation peak is decreased heavily for the shift of input image. If a liquid crystal television(LCTV) without an anlyzer is used as input device, we can get the correlation result regardless of shift of input image because beam path is not changed during storage of holographic filter and correlation process. Also recording time of a holographic matched filter in photorefractive crystal is reduced and the correlation peak is increased because incident beam on the LCTV is transmitted completely. Therefore total optical efficiency is improved. We compared and analyzed the correlation results of proposed photorefractive correlator by computer simulation and optical experiment. We used a BaTiO$_{3}$ single crystal which has high diffraction efficiency in optical experiment.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 ITC-CSCC -3
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• pp.1705-1708
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• 2002

Spreading codes with ZCD(zero-correlation duration) property have the MAI(multiple access interference) rejection ability in the CDMA systems. A class of multi-level spreading codes, i.e., Zero padded ternary ZCD codes are introduced in this paper. By the selected zero-padding method to the binary ZCD codes, ternary ZCD codes are generated and they have enhanced ZCD property and family size than the binary ZCD codes.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2010년도 춘계 학술논문 발표대회 1부
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• pp.225-228
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• 2010

It is an social issue that is various claim related on the defect of apartment house. The cost of defect repair is the most important matter that residents dispute constructers with the huge time wasting and cost loss. For resolve the matter of defect claim, it must to be analyze to the cost property that study and find to pending issue about the cost of defect repair. Therefore this study is investigated the cost property of defect repair relation on correlation analysis and regression analysis around the judgement cost. Consequently, cost of the judgment is associated with cost of the accusation and cost of the defect repair, is recognizable as them that is closely connected. Meanwhile, the more time of take effect and time of lawsuit increase, the more cost of the judgment decrease by draw the regression equation. On the contrary, there are same aspects in the case on the cost of the accusation and cost of the defect repair.

• 한국통신학회논문지
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• 제34권1C호
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• pp.9-14
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• 2009

본 논문에서는 매개 변수가 (N,M,L,1)인 특정 성질을 가진 이진 낮은 상관 구역 수열균(LCZ sequence)를 이용하여 매개 변수가 (2N,2M,L,2)인 4진 낮은 상관 수열군을 생성하는 방법을 제시한다. 본 논문에서 이용하는 이진 낮은 상관 수열군은 balance property를 가지고 있어야 하며, 주기 N이 $N{\equiv}3$ mod 4이어야 하고, 특정한 상관 특성을 가져야 한다. 새로 제안된 생성법은 특정 성질을 가진 이진 낮은 상관 수열군을 이용하여 이진 낮은 상관 수열군을 생성한 Kim, Jang, No, and Chung의 생성법을 응용한 것이다.

• 대한의용생체공학회:의공학회지
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• 제42권4호
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• pp.143-149
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• 2021

In order to predict and prevent the disease of the abdominal aorta, which is the largest artery in the human body and the most common aneurysm, the normal arterial blood flow operation should be considered. To this end, we are trying to solve problems that may arise in the future by executing FSI based on the data obtained from 4D flow MRI. However, to match the similarity between the 4D flow MRI flow and the FSI flow, correlation was used in previous papers, but the correlation did not show the degree of agreement. Therefore, in this paper, we analyzed the correlation between the 4D flow MRI flow velocity of the human abdominal aorta and the two-way FSI flow velocity in which the three physical properties used for the aortic FSI were added to the CT abdominal aorta 3D model and the interclass correlation coefficient. As a result, the physical property M2 showed the highest similarity in correlation and intraclass correlation coefficient, and this property is intended to be helpful in the future study of the abdominal aortic two-way FSI flow rate.

• 대한토목학회논문집
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• 제12권4호
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• pp.49-57
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• 1992

본 연구(研究)는 노화(老化)에 의한 아스팔트시멘트의 물리적 성질변화를 크로마토그램에 근거(根據)하여 유성학적(流性學的)으로 고찰(考察)하였다. 3종류의 AC-20 아스팔트시멘트와 그것을 인공노화(人工老化)시킨 것 그리고 도로(道路)포장의 코어로부터 추출(抽出)해낸 자연노화(自然老化)된 아스팔트에 대하여 3가지 물리적 성질과, 고압(高壓) 겔 투과(透過) 크로마토그래프(HP-GPC)를 이용한 크로마토그램(분자입도분포(分子粒度分布))을 측정(測定)하였다. 이 물리적 성질과 HP-GPC 결과를 분석(分析)하여 노화전후(老化前後)의 크로마토그램과 물리적 성질의 상관관계(相關關係)를 고찰(考察)하였다. 물리적 성질로는 점도(粘度), 동점도(動粘度), 퇴입도(退入度)를 구하였으며, HP-GPC 시험에서는 THF가 순환용액으로 사용되고 RI 검출기가 사용되었다. 크로마토그램을 같은 시간간격(時間間隔)의 10구간으로 분할(分割)하여, 각 구간의 분할면적비(分割面積比)와 물리적 성질이 통계분석(統計分析)에 사용되었다. 이 연구결과(研究結果) 아스팔트시멘트의 물리적 성질은 크로마토그램 특성과 매우 밀접한 관계가 있음을 알 수 있었다. 또한 아스팔트의 노화는 유성학적으로 분자입도의 구성비가 변환되는 과정임을 알 수 있었다.

• 한국결정학회:학술대회논문집
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• 한국결정학회 2000년도 정기총회 및 구정회교수 추모 춘계학술연구발표회
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• pp.28-28
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• 2000

• 한국통신학회:학술대회논문집
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• 한국통신학회 1985년도 추계학술발표회 논문집
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• pp.79-83
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• 1985

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2003년도 춘계총회 및 학술발표회
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• pp.55-55
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• 2003