• 한국철도학회:학술대회논문집
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• 한국철도학회 2008년도 추계학술대회 논문집
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• pp.1782-1793
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• 2008

Republic of korea has begun operating high speed train service according as KTX service operation starts in 2004. Also, EMU whose maximum speed is over 150 kph will be starting to service with electrification and improvement of existing railroad. Moreover, metropolitan electric railways have begun an express service to increase scheduled speed. Therefore, running resistance of rolling stock becomes more important factor effects on the performance. Running resistance of rolling stock is the factor which is necessary for the performance or operation plan of rolling stock, and it's related to rolling friction, slip friction, drag force, gradient, acceleration, curvature, tunnel condition and so on. It is possible to be calculated by CFD (Computational Fluid Dynamics). However it is predicted by experimental equation from running resistance test because of the complex calculation and manifold variables. In this paper, studies about running resistance of rolling stock is introduced, and each term of experimental equation is studied through theoretical approximation. Also, running resistance of rolling stock is estimated by the result of running resistance test, and effects being related to friction, drag force, gradient is examined.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1998년도 IUMRS-ICEM ABSTRACT BOOK
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• pp.85.4-85
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• 1998

• 대한의용생체공학회:의공학회지
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• 제30권4호
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• pp.279-287
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• 2009

Magnetic resonance electrical impedance tomography (MREIT) is a new medical imaging modality providing cross-sectional images of a conductivity distribution inside an electrically conducting object. MREIT has rapidly progressed in its theory, algorithm and experimental technique and now reached the stage of in vivo animal and human experiments. Conductivity image reconstructions in MREIT require various steps of carefully implemented numerical computations. To facilitate MREIT research, there is a pressing need for an MREIT software package with an efficient user interface. In this paper, we present an example of such a software, called CoReHA which stands for conductivity reconstructor using harmonic algorithms. It offers various computational tools including preprocessing of MREIT data, identification of boundary geometry, electrode modeling, meshing and implementation of the finite element method. Conductivity image reconstruction methods based on the harmonic $B_z$ algorithm are used to produce cross-sectional conductivity images. After summarizing basics of MREIT theory and experimental method, we describe technical details of each data processing task for conductivity image reconstructions. We pay attention to pitfalls and cautions in their numerical implementations. The presented software will be useful to researchers in the field of MREIT for simulation as well as experimental studies.

• 농약과학회지
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• 제3권1호
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• pp.96-101
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• 1999

새로운 합성방법을 개발하여 pyrazolate 제초제의 곁가지를 변화시킨 새로운 구조의 3-trifluoro-methylpyrazole 유도체들과 4-benzenecarbinolpyrazole 유도체 등을 합성하여 전작과 답작상태에서 제초활성 시험을 하였다. 밭조건에서는 발아전처리의 경우 4 kg/ha의 약량에서도 제초효과를 나타내지 않았으며 발아후처리에서는 제초효과가 있었으나 미약하였다. 답작상태에서는 4 kg/ha의 약량에서 제초효과가 있었으며 특히 4-benzoylpyrazole의 benzene의 4위치에 electron-donating group인 methoxy가 치환된 화합물의 경우 활성과 선택성이 매우 좋았다. 그러나, methoxy가 두 개 이상 치환되거나 다른 electron-donating group인 sulfide기가 치환된 화합물들의 제초활성은 약하였다.

• 생약학회지
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• 제15권2호
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• pp.61-73
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• 1984

To investigate antitumor component of Lyophyllum decastes, the aqueous extract of its shake-cultured mycelia was subjected to antitumor test against sarcoma 180 cells implanted in ICR mice. The extract showed an inhibition ratio of 65.4% and was found to consist of a polysaccharide moiety and a protein moiety. After purification with DEAE-Sephadex A-50 ion exchange chromatography, Fraction D showed the highest inhibition ratio of 75.7%. The antitumor constituent was examined for immunoaccelerating activity and was found to increase macrophage accumulation in the peritoneal cavity and plaque forming cells of the spleen cells. It was named lyophyllan after the genus name.

• Journal of Chest Surgery
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• 제53권5호
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• pp.243-249
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• 2020

Ebstein anomaly is a rare congenital heart malformation typically involving the tricuspid valve and the right ventricle that has a wide range of anatomical and pathophysiological presentations. Various surgical repair techniques for Ebstein anomaly have been reported because of its near-infinite anatomical variability. Cone repair for Ebstein anomaly can achieve nearly anatomical reconstruction of the tricuspid valve with promising outcomes. In this article, the surgical techniques for cone repair in adult patients with Ebstein anomaly are described in detail, and clinical experiences and technically challenging cases are presented.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.698-702
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• 2001

In this paper, to solve the defect of stand-alone type power system in a remote area, a hybrid power system with photovoltaic/wind/diesel generators is proposed. A hybrid power system has a power-balanced controller to equilibrate generation power with a given load demand and which is composed of common DC power system. To execute a power-balanced control, a hybrid power system is assumed that all of power generators have the characteristics of an equivalent current-source and load sharing control technique must be needed at the same time. So this paper describes the algorithm of interactive technique for design of a hybrid power system.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집(한일합동학술편); 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.836-841
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• 1987

Many kinds of conditioning monitoring technique have been studied, so this study has investigated the possibility of checking the trend in the fault diagnosis of ball bearing, one of the elements of rotating machine, by applying the cepstral analysis method using the adaptive noise cancelling (ANC) method. And computer simulation is conducted in oder to identify obviously the physical meaning of ANC. The optimal adaptation gain in adaptive filter is estimated, the performance of ANC according to the change of the signal to noise ratio and convergence of LMS algorithm is considered by simulation. It is verified that cepstral analysis using ANC method is more effective than the conventional cepstral analysis method in bearing fault diagnosis.

• 한국산업안전학회:학술대회논문집
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• 한국안전학회 2002년도 춘계 학술논문발표회 논문집
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• pp.237-241
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• 2002

국내의 화재로 인한 대형 인명피해를 보면 대부분이 직접적인 화재의 열에 의한 것이 아니라 연기유동을 통한 유해가스들의 흡입을 통하여 또는 대피시 재실자들 간의 사고로 인하여 생기는 것으로서 이글 방지하기 위한 대책이 시급한 상황이다. 이 대책으로써 무엇보다도 건물내의 방화관리자나 건물내 거주자들에 대한 직접적인 교육이 필요하나 건물의 대형화 및 재실자들의 불확실성으로 인하여 교육의 어려움과 무엇보다도 화재의 특성상 실제상황과 같은 구현을 통하여 교육하기에는 불가능 한 실정이다.(중략)

• Journal of Power Electronics
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• 제3권1호
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• pp.40-48
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• 2003

In this paper, a hybrid power system with photovoltaic/wind/diesel generators is proposed to solve the defect of stand-alone type power system in a remote area. A hybrid power system has a power-balanced controller to equilibrate generation power with a given load demand and which is composed of common DC power system. To execute a power-balanced control, a hybrid power system is assumed that all of power generators have the characteristics of an equivalent current-source and load sharing control technique must be needed at the same time. So this paper discusses the structure of power-balance control for hybrid power system. And through the results of simulation, the proposed scheme was verified.