• Title/Summary/Keyword: Large-scale

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A Numerical Study on the Mechanism of Lee Vortex in the Lee of Large Scale Mountain

  • Sung-Dae Kang;Fuj
    • Journal of Environmental Science International
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    • v.1 no.1
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    • pp.45-50
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    • 1992
  • Understanding the nonlinear flow caused by orographic effects can be valuable in siting of new businesses, industries, and transportation facilities. In spite of recent work on large-amplitude waves and wave breaking, the studies of flow around large scale mountains have just begun. The generative mechanism of lee vortices in the lee of large scale mountain Is investigated by Ertel's theorem. The CSU RAMS is used as a numerical model. According to the numerical results, the isentropes are depressed behind the large scale mountains. This means the vortex lines must run upward and downward along the depression surface because vortex lines adhere to isentropic surfaces. Therefore, the vertically oriented vorticity can be formed in the lee of the large scale mountain. This vorticity plays an important role for orographic Precipitation, because strong vertical velocity and cloud bandy are developed along isothermal deformation surface.

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A case study of large-scale slope failure in Granite - Andesite contact area (화강암-안산암 접촉부 대규모 사면의 붕괴 사례 연구)

  • 이수곤;양홍석;황의성
    • Proceedings of the Korean Geotechical Society Conference
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    • 2003.03a
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    • pp.503-508
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    • 2003
  • In this study, we peformed ahead a field geological investigation, boring investigation for slope stability analysis in large scale slope failure area. But the geological stratum was not clearly grasped, because ground was very disturbed by large scale Granite intrusion. Furthermore, the existing test data was not pertinent to the large scale Granite intrusion site like here. Therefore, various kind of field test were performed to grasp clearly for geological stratum. And the results of back analysis, various kind tests used to slope stability analysis.

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An Application of Heuristic Algorithms for the Large Scale Traveling Salesman Problem in Printed Circuit Board Production (회로기판 생산에서의 대형 외판원문제를 위한 경험적 해법의 응용)

  • 백시현;김내헌
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.20 no.41
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    • pp.177-188
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    • 1997
  • This study describes the important information for establishing Human Computer Interface System for solving the large scale Traveling Saleman Problem in Printed Circuit Board production. Appropriate types and sizes of partitioning of large scale problems are discussed. Optimal tours for the special patterns appeared in PCB's are given. The comparision of optimal solutions of non-Euclidean problems and Euclidean problems shows the possibilities of using human interface in solving the Chebyshev TSP. Algorithm for the large scale problem using described information and coputational result of the practical problem are given.

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The Configurations of the large scale UPS system (대규모 무정전 전원공급 시스템의 구성방안)

  • 송언빈;윤병도
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 1991.10a
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    • pp.80-83
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    • 1991
  • The need of UPS (Uninterruptible Power Sup-ply) system is dramatically increasing with the increased use of computers, telecommunica-tion system, building automation system, and office automation system in office buildings. The consequence of the power failure is very disas trous in intelligent office buil-dings. Thus, the nucessity of large scale UPS system with generations of large scale UPS system with generator is increasing. In this study, the configurations of large scale UPS system are reviewed and analyzed. The design guide and technical considerations of high reliability system are presented.

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Robust Decentralized Stabilization of Large-Scale Time-Delayed Linear Systems with Uncertainties via Sliding Mode Control (슬라이딩 모드 제어에 의한 불확정성을 가진 대규모 시간지연 선형 계통의 강인 분산 안정화)

  • 박장환;유정웅
    • Journal of Institute of Control, Robotics and Systems
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    • v.5 no.2
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    • pp.139-144
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    • 1999
  • The present paper is concerned with the robust decentralized stabilization problem of large-scale systems with time delays in the interconnections using sliding mode control. Based on Lyapunov stability theorem and H$_{\infty}$ theory, an existence condition of the sliding mode and a robust decentralized sliding mode controller are newly derived for large-scale systems under mismatched uncertainties. Finally, a numerical example is given to verify the validity of the results developed in this paper.

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A domain-partition algorithm for the large-scale TSP (Large-scale TSP의 근사해법에 관한 연구)

  • 김현승;유형선
    • 제어로봇시스템학회:학술대회논문집
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    • 1991.10a
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    • pp.601-605
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    • 1991
  • In this paper an approximate solution method for the large-scale Traveling Salesman Problem(TSP) is presented. The method start with the subdivision of the problem domain into a number of clusters by considering their geometries. The clusters have limited number of nodes so as to get local solutions. They are linked to give the least path which covers the whole domain and become TSPs with start- and end-node. The approximate local solutions in each cluster are obtained by using geometrical property of the cluster, and combined to give an overall-approximate solution for the large-scale TSP.

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A Study on Competition Analysis in Retail Distribution Industry Using GIS in Seoul

  • YOO, Byong-Kook;KIM, Soon-Hong
    • Journal of Distribution Science
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    • v.19 no.3
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    • pp.49-60
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    • 2021
  • Purpose: This study aims to utilize geographic data to analyze how various retail formats of large-scale stores around the traditional market affect the performance of the traditional market in Seoul, Korea. Research design, data, and methodology: The two types of catchment areas were demarcated (circle of 1km radius and Thiessen polygon) for each traditional market, and the large-scale stores located within each catchment area were identified for 153 traditional markets in Seoul, Korea. Additionally, multiple regression analysis was utilized. Results: The results revealed that the influence on the performance of the traditional markets were different depending on the retail format of the large-scale stores. Large discount stores were found to have a negative effect on the sales and the visitors of traditional markets, whereas complex shopping malls and department stores had a positive effect on the traditional markets. Conclusions: As a result of the differences in the retail format such as product categories and leisure functions, the impact of some large-scale stores on the traditional market may have a greater agglomeration effect than the consumer churn effect. Therefore, it is suggested that in the regulation of these large-scale stores, the differences in retail format should be considered for the future.

A Study on Efficiency Estimation of Aquaculture : the Case of the Korean Seaweed Farms (해조류 양식업 규모의 효율성 추정에 관한 연구 - 부산 기장지역 미역양식을 중심으로 -)

  • Seo, Ju-Nam;Song, Jung-Hun
    • The Journal of Fisheries Business Administration
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    • v.40 no.1
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    • pp.1-26
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    • 2009
  • The aquaculture management considers the maintenance of households lifehood more than profit maximization. As aquaculture industry has developed enterprise farms appeared, and the small and the large scale farms coexist. The features of coexistence could be summarized as followings. First of all, the large scale farms show the higher net profit while the small scale farms show the higher profit per 1ha and the earning rate. Secondly, in the case of over 2ha, the earning rate is stable in spite of the scale expansion. Moreover, in processing method, dried seaweed occupy the biggest proportion in the small scale farms while the raw seaweed occupy the biggest proportion in the large scale farms. Lastly, the scale of farms becomes larger, the participation rate of household labor rises. This thesis analyses the efficiency of Korean seaweed farms in the way of DEA model and suggests the improvements for the efficiency management. The mean technical, pure technical and scale efficiencies were measured to be 0.88, 0.96 and 0.91, respectively. Among the 20 farms included in the analysis, 10 were technically efficient and 12 were scale efficient. In conclusion, it is shown that the aquaculture farms has been becoming the form of coexistence. This appearance results in the effort for reducing the cost in the small scale farms and in profit maximization in the large scale farms. On the other hand, middle scale farms is inefficient compared with the small or large scale farms. Therefore, in order to achieve the efficiency, it is necessary to accomplish economy of scale by extending farm size or to cut expenses by reducing farm area. In other word, the efforts for achieving the efficiency is required in a different direction in spite of the same scale.

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Analysis on NDN Testbeds for Large-scale Scientific Data: Status, Applications, Features, and Issues (과학 빅데이터를 위한 엔디엔 테스트베드 분석: 현황, 응용, 특징, 그리고 이슈)

  • Lim, Huhnkuk;Sin, Gwangcheon
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.7
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    • pp.904-913
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    • 2020
  • As the data volumes and complexity rapidly increase, data-intensive science handling large-scale scientific data needs to investigate new techniques for intelligent storage and data distribution over networks. Recently, Named Data Networking (NDN) and data-intensive science communities have inspired innovative changes in distribution and management for large-scale experimental data. In this article, analysis on NDN testbeds for large-scale scientific data such as climate science data and High Energy Physics (HEP) data is presented. This article is the first attempt to analyze existing NDN testbeds for large-scale scientific data. NDN testbeds for large-scale scientific data are described and discussed in terms of status, NDN-based application, and features, which are NDN testbed instance for climate science, NDN testbed instance for both climate science and HEP, and the NDN testbed in SANDIE project. Finally various issues to prevent pitfalls in NDN testbed establishment for large-scale scientific data are analyzed and discussed, which are drawn from the descriptions of NDN testbeds and features on them.

Numerical study of Particle Motion in a Developing Mixing Layer using Large-eddy Simulation (LES를 이용한 발전하는 혼합층에서의 입자 운동에 관한 수치 해석 연구)

  • Kim, Tae-Jin;Seo, Tae-Won
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.94-99
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    • 2001
  • The numerical simulation of the particle dispersion in the vortical flows provides insight into the mechanism of particle-fluid interaction. The simulation results show that the mixing layers are characterized by the large-scale vortical structures undergoing pairing process. The particle dispersion is strongly influenced by the large-scale structures and the particle sizes. The analysis shows that the mixing layers grows like a step-function.

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