• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.479-483
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• 1998

Many computer models have been used for estimating the water quality and evaluating countermeasures. The models such as QUAL2E, STREAM, WASP, CE-QUAL have been applied in the waters so far. Some modeller assumed either that the flow of the waters is steady or that the storage change of the waters is negligible. And someone excluded hydraulic part from the quality simulation. It may cause inaccurate estimations of water flow and quality, particularly when the waters have seawards boundary and more inflow than outflow, etc. In order to show the velocity vector for water quality simulation of Paldang lake in dynamic condition, RMA-2 was performed with the water quantity data in 1997.

• 한국음향학회:학술대회논문집
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• 한국음향학회 1992년도 학술논문발표회 논문집 제11권 1호
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• pp.76-80
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• 1992

We consider the tapped-delay line (TDL) equalizer with the few calculation quantity and the simplity, the decision feedback equalizer (DFE) with the good property for interference, and lattice equalizer(LE) with high insensitivity to roundoff noise in mobile communication fading channel. The used adaptive algorithm is the LMS algorithm and RLS algorithm. In this paper, we have evaluated the performance of the TDL equalizer, the decision feedback equalizer, and lattice-structured equalizer, for the digital signal corrupted by the impulsive noise and the white gaussian noise under the fading channel environment. From the results of error performance analysis, it is confirmed that lattice-structured equalizer has better performance than DFE equalizer and TDL equalizer.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2004년도 학술대회 논문집
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• pp.229-232
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• 2004

This paper is about the new Distribution System of the electric customers. The Power loss in the Distribution System is disregarded and rarely managed so far. But, economically, this loss is not small quantity to Ignore. So, in this paper, we suggest that the new Distribution System of the electric customer by simply changing the locations of Power Transformer and other power facilities which is located inside of the customer. And we also show that the Power loss is decreased with this systematic changing by approximated calculation.

• 품질경영학회지
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• 제5권1호
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• pp.3-10
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• 1977

The research on the process capability is the basis for quality design, operation standard and so on. In this study, histogram of the measured value for the cutting process and calculation of the capability factor Cp are established, resulting in the classification of 4 grades, and necessary measures for them are presented. The advancement of productivity is the most significant result of this study. The processing time per piece for those stabilized processes having the capability factor 1.33 and above is lessened, and the advancement in quantity capability is made possible permitting dispersion of standard up to the tolerance limit. The exact knowledge of process capability is most important for the quality design system. For the efficient application of this result of the research, a systematic and positive cooperation by the whole company members is needed.

• 한국방재학회 논문집
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• 제3권3호
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• pp.165-171
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• 2003

2002년 태풍 루사의 집중호우로 금강 중상류에 위치한 초강천 유역에 막대한 홍수피해와 범람을 동반하였다. 발생한 홍수는 초강천 하류에 위치한 송천교에 부설되어 있는 송천 수위국을 잠식하여 붕괴시킬 정도로 엄청난 유량 규모를 가졌기 때문에 직접 측정할 수 없었다. 이에 본 연구에서는 매닝의 등류 공식을 이용하여 홍수량을 산정함과 더불어 적정한 조도계수를 제시하였다.

• 한국안전학회지
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• 제33권3호
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• pp.83-91
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• 2018

This paper suggests a weibull time delay model to evaluate failure risks in FMEA(failure modes and effects analysis). Assuming three types of loss functions for delayed time in failure cause detection, the risk of each failure cause is evaluated as its occurring frequency and expected loss. Since the closed form solution of the risk metric cannot be obtained, a statistical computer software R program is used for numerical calculation. When the occurrence and detection times have a common shape parameter, though, some simple results of mathematical derivation are also available. As an enormous quantity of field data becomes available under recent progress of data acquisition system, the proposed risk metric will provide a more practical and reasonable tool for evaluating the risks of failure causes in FMEA.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2011년 춘계학술대회논문집
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• pp.141-147
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• 2011

A two-phase numerical model for plate-fin heat exchangers with plain fins and wave fins is studied incorporating the thermodynamic properties and the characteristics of fluid flow. The numerical simulations for the two fins in cryogenic conditions are earned out by employing a homogenous two-phase flow model with the CFD code ANSYS CFX. The heat transfer coefficients and the friction factor for nitrogen saturated vapor condensation process inside two types of plate fin heat exchanger are evaluated including the effects of saturation temperature (pressure), mass flow rate and inlet vapor quantity. The convective heat transfer coefficients and friction factors will be used for design of plate-fin type heat exchangers operating under cryogenic conditions.

• 한국군사과학기술학회지
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• 제9권1호
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• pp.13-23
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• 2006

A propellant mainly consisting of nitric ester including nitrocellulose and nitroglycerine is characteristic of being decomposed naturally. And this phenomenon is known as being affected mostly by its storing temperature and humidity. In this research, the effect of storing temperature and humidity on self life has been studied by measuring the contained quantity of residual stabilizer of propellant KM30Al, which are parts of 155MM propelling charge K676 and K677; the method for the measurement is acceleration aging test, and decomposition reaction equation, Eyring Equation and Berthlot Equation were used for the calculation. As result of this study, it was found that the storing temperature influenced seven times as large as the storing humidity upon the self life of the propellant KM30Al, Furthermore, especially in the high temperature region, the storing temperature had a dominant effect on the self life.

• 환경위생공학
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• 제23권3호
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• pp.47-57
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• 2008

This study was predicted the diffusion of the conservative contaminant using a two-dimensional hydraulic model. The research area is upper basin of Jakwang river where the possibility where the pollutant of vast quantity will flow is high. Using SMS model, we calculated two-dimensional stream flow. And using this result, predicted the conduct of the conservative contaminant by pollutant transfer diffusion calculation. And also we predicted flow and contaminant diffusion in the near estuary by constructed guide bank. As a result of study, pollutant effect scope of the conservative contaminant was predicted with the fact that will broaden because of interception by guide bank. As discharge was increased from the Jakwang river, The diffusion of the pollutant is accelerated, also the effect scope increases.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2005년도 춘계 학술대회
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• pp.344-349
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• 2005

Neutron count rate measurements to assay fissile content of uranium powder have been carried out in a neutron counter. The induced fission neutrons by Cf-252 neutron source are counted as the variation of fissile material in fuel material. The measured counts are compared with equivalent results obtained from calculation. It shows that the measured neutron counts versus quantity of $UO_2$ powder enrichment agreed reasonably well with the calculated values.