• Proceedings of the Korea Water Resources Association Conference
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• 2006.05a
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• pp.1425-1430
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• 2006

상수도 관망해석에 있어 수요량 추정 방법은 자료의 형태와 관망해석의 정확도 추구 정도 등에 따라 다양한 방법으로 추정할 수 있다. 통상 상수도관망해석을 수행할 때에 사용되는 수요량추정 방법은 과거사용량을 추세분석하여 장래 계획에 필요한 목표연도까지의 원단위를 산정하고 이 자료를 바탕으로 행정구역상 동단위나 병합계량구역(Block system)단위까지 수요량을 산출한 후 수요량 산출 구역 내 해석 관망상에 위치하는 격점 또는 관로에 적정한 수요량을 분배하는 방법을 사용한다. 결국 산정된 수요량 자료는 행정동 단위나, 병합계량구역 단위 정도의 수요량을 산출하고, 해당 구역내에 분포하는 관망 구성상 절점수에 따라 등분하여 배분하거나, 절점이 담당하는 면적별로 수요량을 산출하여 관망해석을 실시하게 된다. 이러한 방법은 작업시간이 오래 걸리고 수요량 추정 단위에 따라 정확도가 달라지는 문제가 있다. 본 연구에서는 인천시를 대상으로 MIKE-NET 프로그램에서 제공하고 있는 수요량 배분 기능을 이용하여 각 절점의 수요량을 배분하는 방법과 기존 수요량 배분 방법을 비교함으로 수요량 적용 방법이 배수관망해석에 미치는 영향을 살펴보았다.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.5
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• pp.344-351
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• 2010

Uncertainty analysis on the net flow discharge (NFD) influencing the long-term material transport and the simulation results of the salinity and COD concentration distribution using the MIKE21 diffusion model in Gyeonggi bay and Han-River estuary is carried out. The NFD flowing the Gyodongdo - Seokmodo channel via the North channel of Ganghwado is estimated about 97% of the total NFD and the NFD of the Yeomha channel is estimated as only $2.5{\sim}3.0%$. On the other hand, the uncertainty defined as the difference by the different time-scale data input is analysed by the comparison of the model simulation result of the salinity and COD concentration distribution. One is computed based on the daily river flow data, and the other is computed based on the monthlymean river flow data. The results show that the salinity and COD concentration differences are about -10~20 psu and ${\pm}1.0\;mg/L$ during the summer season having a high flow discharge in Yeomha channel, respectively. The difference is clearly negligible in the open sea area.

• Nuclear Engineering and Technology
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• v.45 no.6
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• pp.731-744
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• 2013

Energy security is a topic of high importance to many countries throughout the world. Countries with access to vast energy supplies enjoy all of the economic and political benefits that come with controlling a highly sought after commodity. Given the desire to diversify away from fossil fuels due to rising environmental and economic concerns, there are limited technology options available for baseload electricity generation. Further complicating this issue is the desire for energy sources to be sustainable and globally scalable in addition to being economic and environmentally benign. Nuclear energy in its current form meets many but not all of these attributes. In order to address these limitations, TerraPower, LLC has developed the Traveling Wave Reactor (TWR) which is a near-term deployable and truly sustainable energy solution that is globally scalable for the indefinite future. The fast neutron spectrum allows up to a ~30-fold gain in fuel utilization efficiency when compared to conventional light water reactors utilizing enriched fuel. When compared to other fast reactors, TWRs represent the lowest cost alternative to enjoy the energy security benefits of an advanced nuclear fuel cycle without the associated proliferation concerns of chemical reprocessing. On a country level, this represents a significant savings in the energy generation infrastructure for several reasons 1) no reprocessing plants need to be built, 2) a reduced number of enrichment plants need to be built, 3) reduced waste production results in a lower repository capacity requirement and reduced waste transportation costs and 4) less uranium ore needs to be mined or purchased since natural or depleted uranium can be used directly as fuel. With advanced technological development and added cost, TWRs are also capable of reusing both their own used fuel and used fuel from LWRs, thereby eliminating the need for enrichment in the longer term and reducing the overall societal waste burden. This paper describes the origins and current status of the TWR development program at TerraPower, LLC. Some of the areas covered include the key TWR design challenges and brief descriptions of TWR-Prototype (TWR-P) reactor. Selected information on the TWR-P core designs are also provided in the areas of neutronic, thermal hydraulic and fuel performance. The TWR-P plant design is also described in such areas as; system design descriptions, mechanical design, and safety performance.