• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 C
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• pp.1939-1940
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• 2002

Numerical simulation for effect of chirp on PMD and PDL was accomplished. we assumed two uniform fiber concatenation with both polarization mode dispersion and polarization-dependent loss. We showed that polarization mode dispersion is increased with chirp parameter and polarization-dependent loss is decreased with chirp. And we accomplished mathematical analysis.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 1997년도 춘계학술대회논문집; 경주코오롱호텔; 22-23 May 1997
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• pp.473-480
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• 1997

This paper presents the feasibility of the assumption that incident sound to panels might have a Gaussian distribution, instead of the well-known uniform distribution in the analysis of sound transmission loss of panels. Being compared with the latter, it seems that the former is physically more concrete. To prove the assumption, the problems with diffuse fields in reverberation room are considered by case study and comparisions of the prediction with the measurement of sound transmission loss of walls are performed. The results show good agreement between the two values.

• 한국시뮬레이션학회:학술대회논문집
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• 한국시뮬레이션학회 2003년도 춘계학술대회논문집
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• pp.185-190
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• 2003

이산사건 시스템을 기술하는데는 다양한 방법론들이 있으며 event의 관점에서 본다면, event loss 방법론과 event lossless방법론이 있다. event loss방법론의 경우 때때로 원치 않는 event loss가 발생하여 시스템을 deadlock의 상태로 이끌 수가 있으며, 이러한 것을 피하기 위해 본 논문은 event loss방식의 동기식방법론인 DEVS형식론으로 기술된 모델을 본 논문에서 제안하는 TSRG란 방법을 이용하여 event loss의 유무를 해석할 수 있는 기법을 소개하고자 한다. 소개된 해석 기법은 linear programming을 이용하여 해를 구할 수 있으며, DEVS형식론으로 기술된 이산사건 모델들간의 event loss의 유무를 해석함으로써 서로간의 통신 동기화의 가능성 분석을 가능하도록 한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 1998년도 창립기념 춘계학술대회 논문집
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• pp.249-256
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• 1998

Design target values of transmission loss in a high-speed train wall are suggested by calculating the difference between interior and exterior noise levels of it. Exterior noise level distribution on the boundary of train wall is calculated by Sysnoise, with sound source input prepared by experiments. Two kinds of exterior sound sources are considered, the rolling noise of train wheels on the rail and the aerodynamic noise from the pantograph. Interior noise level is provided by high-speed design target. Transmission loss characteristics according to the frequency band are examined.

• 산업기술연구
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• 제27권B호
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• pp.71-75
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• 2007

A cylindrical pin fin with variable diameter is analyzed by using the one dimensional analytical method. Heat loss and fin efficiency are presented as a function of the fin diameter, length and convection characteristic numbers ratio. The relationship between the fin diameter and convection characteristic number over the fin for the same amount of heat loss is shown. One of the results indicates the fin efficiency increases as the fin diameter increases while that decreases as the fin length increases.

• Journal of the Korean Statistical Society
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• 제31권3호
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• pp.405-413
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• 2002

We consider a finite dam with general inputs and adopt the level crossing approach to obtain explicit formulas of the expected wet period, the expected loss of water due to overflows in a wet period, and the long-run proportion of loss in inputed water.

• 한국자기학회:학술대회 개요집
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• 한국자기학회 2008년도 Asian Magnetics Conference
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• pp.178-178
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• 2008

This paper presents an efficient approach for simulating the loss of the laminated core joints in power transformers. Two laminated core models, with the same material and joint type but different leg length, are established for validating the specific total loss inside the joint region.

• 대한기계학회논문집B
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• 제22권1호
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• pp.70-78
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• 1998

The present study has tested semi-empirical loss models for a reliable performance prediction of mixed-flow pumps with four different specific speeds. In order to improve the predictive capabilities, this paper recommends a new internal loss model and a modified parasitic loss model. The prediction method presented here is also compared with that based on two-dimensional cascade theory. Predicted performance curves by the proposed set of loss models agree fairly well with experimental data for a variety of mixed-flow pumps in the normal operating range, but further studies considering 'droop-like' head performance characteristic due to flow reversal in mixed-flow impellers at low flow range near shut-off head are needed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2008년도 추계학술대회논문집
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• pp.152-157
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• 2008

Enclosure is widely used for the sound insulation in a ship. But it is very difficult to estimate the sound insertion loss for the enclosure because the sound field between the enclosure and the machine is so complex. Therefore, it is usually estimated experimentally. In this research, sound insertion loss of the enclosure is estimated by theory assuming that the sound field in the enclosure is reverberation field. And the results from the theory are compared to those from the experiment.

• 전기학회논문지
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• 제59권3호
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• pp.575-580
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• 2010

This paper is to design an optimum power conversion device for the system required for development of a low cost 3-phase power inverter. For this purpose, in order to meet with endurance required by the industry, failure mode is standardized to guarantee lifetime of a power semiconductor by monitoring real time power loss and to facilitate failure mode analysis. As normality of heat loss of a power semiconductor is identified remaining in a certain range by comparing heat rise slope between that is calculated by using average current or average loss and that is measured at a heat sink, its feasibility is confirmed by experiment.