• Nuclear Engineering and Technology
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• v.25 no.2
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• pp.248-254
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• 1993

The purpose of this study is to evaluate the thermal safety for dry transport of a shipping cask. Analysis condition was based on an ambient temperature of 38$^{\circ}C$ for normal heat condition. The cask was designed to carry 4PWR spent fuel assemblies with a burnup of 38,000 MWD/MTU and 3 years of cooling time. Thermal analysis was carried out by using the COBRA-SFS code. The fuel cavity was considered to be filled with air, nitrogen or helium gas for dry transport. The results of analysis showed that the maximum temperatures of fuel rod cladding in air and helium cavity would be 277$^{\circ}C$ and 226$^{\circ}C$, respectively, for 3 years of cooling time. These values were less than the specified temperature to maintain the thermal integrity of fuel assembly for dry transport.

• Journal of the Korean Society of Propulsion Engineers
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• v.8 no.4
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• pp.16-25
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• 2004

Theoretical analysis for predicting the heat transport limitation of a copper powder sintered wick heat pipe was performed. The heat pipe diameter was 8mm and water was used for working fluid. The particle diameter was classified by 5 different meshes, and each capillary pressures and heat transport limitations. thermal resistances were analyzed according to the operating temperatures, wick thicknesses and inclination angles, based on the effective capillary radius($r_c$), porosity($\varepsilon$), Permeability (K). The wick capillary limitation was increased according as the particle diameter and the wick thickness and the operating temperature were increased. As the porosity and the capillary radius were larger. then the heat transport limitation was higher. The thermal resistance was greatly increased according as the wick thickness was increased.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2000.11a
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• pp.163-171
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• 2000

AMBIDEXTER 원자력 에너지 시스템은 Th$^{233}$ /U 핵주기를 이용한 용융염 핵연료가 내장형 열교환기를 포함하는 일체형 원자로 시스템을 순환하면서 1차 냉각 계통을 이루고, 독립된 온라인 정화계통에 의해 액상 용융염 핵연료 일부를 연속 추출. 처리, 재주입 함으로 노심의 핵적 자활상태를 유지한다. 이와 같은 시스템 개념은 배관망 파손에 의한 중대사고 방지, 열수송 회로와 방사성 물질 회로의 독립적 구성을 통한 효과적인 원자력 에너지 이용과 고유 안전성을 확보하는 장점을 통해 현안 원자력 문제의 근본적인 해결 방안을 제시하고 있다.(중략)

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2007.11a
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• pp.187-192
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• 2007

A project is being implemented to develop the long distance energy transport technology using the chemical reactions. This project can be classified into three main research categories covering heat recovery reaction, long distance energy transport, and heat generation reaction. In this study, the methanol is selected as a system material since it shows several unique superior characteristics as follows: gaseous state of reactant and product, large heat of reaction, high yields of reaction at relatively low temperature, and also steady and economical supply. Furthermore, it is anticipated that the outcomes of this study can be widely applied to the related industries. A feasibility study was carried out to evaluate the economics of this technology which study was based on the following case: 10,000 households, 15km distance energy transportation, utilization of waste heat from power plant.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.30 no.8
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• pp.45-53
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• 2001

열적 성질을 가지는 각종 용질을 물을 주체로 한 열매체 등에 혼합 분산시킴으로써 그 열매체인 유체의 성질을 바꾸어 다원적 기능성을 가지도록 한 기능성 열유체의 열에너지 수송성에 대해 살펴보고자 한다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.13 no.2
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• pp.93-102
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• 2013

This paper proposes an algorithm designed to obtain the optimal solution for transportation problem. The transportation problem could be classified into balanced transportation where supply meets demand, and unbalanced transportation where supply and demand do not converge. The archetypal TSM (Transportation Simplex Method) for this optimal solution firstly converts the unbalanced problem into the balanced problem by adding dummy columns or rows. Then it obtains an initial solution through employment of various methods, including NCM, LCM, VAM, etc. Lastly, it verifies whether or not the initial solution is optimal by employing MODI. The abovementioned algorithm therefore carries out a handful of complicated steps to acquire the optimal solution. The proposed algorithm, on the other hand, skips the conversion stage for unbalanced transportation problem. It does not verify initial solution, either. The suggested algorithm firstly allocates resources so that supply meets demand, in the descending order of its loss cost. Secondly, it optimizes any surplus quantity (the amount by which the initially allocated quantity exceeds demand) in such a way that the loss cost could be minimized Once the above reallocation is terminated, an additional arrangement is carried out by transferring the allocated quantity in columns with the maximum cost to the rows with the minimum transportation cost. Upon application to 2 unbalanced transportation data and 13 balanced transportation data, the proposed algorithm has successfully obtained the optimal solution. Additionally, it generated the optimal solution for 4 data, whose solution the existing methods have failed to obtain. Consequently, the suggested algorithm could be universally applied to the transportation problem.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.13 no.1
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• pp.80-87
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• 2001

Global robust diagnostic models are established based on MOM of GFDL to study the circulation in the world ocean. The horizontal grid sizes 1/2 degree, and the vertical water column is divided into 21 levels. The hydrographic data are taken from Levitus et al.(1994) and the wind stress from Hellerman and Rosenstein (1983). Based on the model results the horizontal volume, heat and salt transports across some representative sections are calculated. The preliminary results show that Though the cross-equator volume transports in the Atlantic, Indian and Pacific Oceans are all small, the heat transports across equator in the Atlantic are northward. This is clearly a result of the southward flow of the North Atlantic Deep Water and the northward compensating warm flow in the upper layer. The annual mean of the cross-equator heat transport in the Pacific Ocean from the present model is significantly lower than that calculated by Philander et at. (1987). This might indicate the importance of the Indonesian Throughflow in the heat transport in the Pacific Ocean. Our calculation shows that the heat transport through the Indonesian Archipelago is 0.5 PW, which is comparable with the poleward heat transport in the North Atlantic and Pacific Oceans. The difference in heat transports across the sections 5 and 6 demonstrates the important role of the Agulhas Current in the heat balance of the world ocean.

• Journal of the Korean GEO-environmental Society
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• v.22 no.11
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• pp.15-21
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• 2021

Losses of both life and property increased from damage to underground pipe such as heat transmission pipe buried underground in downtown because pipes are gradually aging. Considering the characteristics of the heat transmission pipe, which is not exposed to the outside and difficult to immediately identify problems such as damage, it is realistic to indirectly check the condition of the facility based on the historical information that is periodically collected through facility maintenance. In this study, a methodology for estimating the damage probability was developed by examining the history information of the heat transmission pipe, deriving an evaluation factor that is related to the damage probability. The contribution factor of the damage probability were reviewed by analyzing not only the guidelines for maintenance of heat transmission pipe of advanced European countries and domestic district heating companies, but also the cases of waterworks with similar characteristics. Evaluation factors were selected by considering not only the correlation with the damage probability but also the possibility of securing data. Based on 1999, when the construction technology and standards of heat transmission pipe changed, the damage probability estimation function according to the period of use was divided into the case of being buried before 1998 and the case of being buried after 1999, and presented. In addition, the damage probability was corrected by assigning weights according to the measured data for each evaluation factor such as the diameter, use, and management authority.

• 열병합발전
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• s.62
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• pp.23-26
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• 2008

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1998.10a
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• pp.9-14
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• 1998

“폐열을 이용한 도시에너지 시스템”은 산업단지나 발전소 등에서 발생되는 폐열을 회수하여 원격지로 수송을 하고, 도시지역의 수요처에서 수송된 열을 효율적으로 이용하는 에너지 시스템이다. 본 연구는“폐열을 이용한 도시에너지 시스템”모델링을 위해 시스템을 폐열공급원에서 최종 열수요처까지의 전체시스템을 이루는 GES(Global Energy System)와 열의 입출력·이송 저장·변환이 이루어지는 EFS(Energy Flow System)로 구분하였다. 그리고 EFS를 프로세스별로 구분하고, 이들을 최적화하는 시스템 모델링을 구축하였다.