• 전력전자학회:학술대회논문집
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• 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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• pp.480-483
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• 2001

Recent power quality measurement projects report that voltage sags are the most frequent disturbances in the sites [1]-[4]. DVRs were emerged as the best effective and economic solution for this problem [11]. This paper analyzed the power flow of a DVR in distribution grids. This paper showed various operation modes and boundaries such as inductive operation, capacitive operation, and minimal power operation beside the in-phase compensation.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2004년도 춘계학술대회 논문집
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• pp.1247-1252
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• 2004

ATC(Automatic Train Control) system employed in Bundang urban transit is operated in accordance with automatic blocking equipment. Using AF(Audio Frequency) track circuits installed at a block section, the block signal is automatically controlled and the safety of train operation is supported. In this paper, we investigate the operation mode of bundang urban transit and analyze the operation algorithm of ATC on-board system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 C
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• pp.1510-1513
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• 1999

Carried out simulation for yearly peak and March load time of the KEPCO Power System in 1999. Analysis of the problems in power system operation by powerflow, fault and stability study. Establishment of power system optimal operating plan by installation of power system stabilizer.

• 간호행정학회지
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• 제22권5호
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• pp.415-423
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• 2016

Purpose: The purpose of this research was to provide patients with safe preoperative preparatory procedures by removing any risk factors from the preparatory procedures by using failure mode and effects analysis, which is a prospective risk-managing tool. Methods: This was a research design in which before and after conditions of a single group were studied, Failure mode and effects analysis were applied for the preparatory procedures done before operations. Results: The preparation omission rate before the operation decreased from 2.70% to 0.04%, and operation cancellation rate decreased from 0.48% to 0.08%. Conclusion: Failure mode and effects analysis which remove any risk factors for patients in advance of the operation is effective in preventing any negligent accidents.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.519-520
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• 2006

The aim of this study was biomechanical analysis of shelf operation in patients with dysplastic hip joint by finite element contact analysis. Two dimensional CT images were used to construct the finite element models to analyze the contact pressure, and the 3D expansion of the Ninomiya's method was used in the calculation of the resultant force in the hip joint. The surgery recovered the center-edge angles to the normal anatomical range and increased the contact areas in two patients. The maximum contact pressures and von-mises stresses were decreased. The present study provides the biomechanical guideline of optimal surgical parameters to maximize the surgical efficiency and the clinical outcomes in dysplastic hip joint using the shelf operation.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2003년도 학술대회지
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• pp.266-269
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• 2003

도로시설물의 수명동안 비용이 최소가 되는 최적의 건설 및 유지관리 전략을 수립하기 위해서는 시설물에 대한 체계적인 LCC분석이 이루어져야 하지만 아직 국내 건설프로젝트 중 토목시설물에 대한 LCC연구는 거의 이루어지지 못하여 이에 대한 기초적 연구 및 실적자료가 절실히 필요한 시점에 와 있다. 본 연구에서는 사례교량의 LCC분석을 통해 유지관리 실태를 파악하고, 장래 요구되는 유지관리수준과의 비교분석을 통해 적정유지관리수준을 제시함과 동시에 아직 사례가 별로 없는 교량구조물에 대한 실적 LCC 기초자료를 얻고자 하였다. 본 연구를 통해 LCC 측면에서 볼 때, (1) PSC교나 RC교에 비해 강교가 경제적임을 알 수 있었으며, (2) 향후 더욱 적극적인 유지관리가 필요한 것으로 분석되었다.

• 한국산림과학회지
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• 제102권1호
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• pp.143-155
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• 2013

효율적인 임목수확작업시스템 구축과 프로그램을 개발하기 위한 기초자료를 제공할 목적으로 GIS에 의한 조망권 분석기법을 활용하여 GIS를 이용한 집재작업 가능구역 분석 및 노망배치를 위한 기법을 작성하고 적용성을 검토하였다. 집재작업 가능구역 분석결과, 집재작업 가능구역의 면적 비율은 최대집재거리가 길어질수록 지형의 영향 때문에 줄어들었으며, 집재작업 불가능구역에 추가로 임도망을 개설하여 노망개설 전후를 비교 분석한 결과, 집재작업 가능구역이 증가하는 것을 알 수 있었다. 신규로 노망배치를 실시할 경우, 노망의 배치형태에 따라 집재작업 가능구역이 달라지므로 GIS 노망배치기법을 적용하여 신규 노망배치에 따른 집재작업 가능구역을 비교 분석한 결과, 집재작업 가능구역이 최대로 되는 가장 효율적인 최적의 노망배치를 구축할 수 있었다. 본 연구결과는 GIS를 이용한 효율적인 임목수확작업시스템의 구축과 이를 위한 프로그램의 개발에 적용할 수 있는 기초자료가 될 것으로 사료된다.

• Journal of international Conference on Electrical Machines and Systems
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• 제1권4호
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• pp.498-504
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• 2012

The water-cooled Permanent Magnet Linear Synchronous Motor (PMLSM) has a wide range of applications due to high efficiency, high thrust force density and high acceleration. In order to ensure normal operation and maximum output, both the magnetic and thermal performance are vital to be considered. Based on ANSYS software, electromagnetic and thermal finite-element analysis (FEA) models of a 14-pole, 12-slot water-cooled PMLSM are erected adopting suitable assumptions. Firstly, the thrust force and force ripple with different current densities are calculated. Secondly, the influence of different water flow on the motor heat dissipation and force performance under different operationional conditions are investigated and optimized. Furthermore, for continuous operation, the temperature rise and thrust feature are studied under the rated load 8A, the proper temperature $120^{\circ}C$ and the limited temperature $155^{\circ}C$. Likewise, for short-time operation, the maximum duration is calculated when applied with a certain large current. Similarly, for intermittent operation, load time as well as standstill time are determined with the optimal current to achieve better thrust performance.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.98-100
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• 2005

This paper describes link analysis on the processed data, HRIT (High Rate Information Transmission) and LRIT (Low Rate Information Transmission), for the preliminary design of interface between COMS (Communication, Ocean and Meteorological Satellite) and ground station. At the MODAC (MeteorologicaVOcean Data Application Center), the processed data are transmitted to user station via COMS with normalization and calibration by pre-processing of MI (Meteorological Imager) data. Due to consider satellite as radio relay, overall analysis containing uplink and downlink is needed. Specific link parameters can be obtained with using the outcomes of SRR (System Requirement Review) which was held on 13-14 June 2005, in Toulouse. From the relation between overall link margin and output power of HPA (High Power Amplifier) of MODAC, it is shown that even though the minimum power related with COMS receiving power range is transmitted at MODAC, the obtained link margin of HRIT could be above 3 dB at user station which antenna elevation angle is 10 degree.

• 전기학회논문지
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• 제63권9호
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• pp.1219-1226
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• 2014

This paper introduces a hardware simulator for the LVRT operation analysis of the grid-tied PMSG wind power system with a power dissipation circuit. The power dissipation circuit, which is composed of chopper and resistor, suppresses the sudden increase of DC-link voltage in the back-to-back converter of the grid-tied PMSG wind power system. The LVRT operation was first analyzed using computer simulations with PSCAD/EMTDC. A wind power simulator including the power dissipation circuit and the fault simulator composed of variac and IGBT were built to analyze the LVRT operation. Various experiments were conducted to verify the effectiveness of the power dissipation circuit for the LVRT operation. The developed hardware simulator can be extensively utilized for the analysis of various LVRT operations of the grid-tied wind power system.