• Title/Summary/Keyword: Small scale system

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Review of Uncertainties in Applying GIS Data and Hydrological Models to Evaluate the Effectiveness of Best Management Practices (수리모델과 GIS 데이터를 이용한 최적관리방안의 평가에 대한 불확실성의 재고)

  • Lee, Tae-Soo
    • Journal of the Korean association of regional geographers
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    • v.17 no.2
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    • pp.245-258
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    • 2011
  • Best management practices (BMPs) are widely accepted and implemented as a mitigation method for soil erosion and non-point source problems. Estimating the amount of soil erosion and the effectiveness of BMPs using hydrological models help to understand the condition, identify the problems, and make plans for conservation practices in an area, typically a watershed. However, the accuracy and reliability of assessment of BMP impacts estimated by hydrological models can be often questionable due to the uncertainties from various sources including GIS(Geographic Information System) data, scale, and model. This study reviewed the development and the background of hydrological models, and the modeling issues such as the selection of models, scale, and uncertainties of data and models. This study also discussed the advantage of a small scale and spatially distributed model to estimate the impacts of BMPs.

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A Study on Development of a Marine Docking System for Repair of a Small Coast-Boat (연안 소형선박 수리용 해상 상가시스템 개발)

  • Park, Chung-Hwan;Jang, Dong-Won;Yang, Hyang-Kweon;Jin, Jong-Ryung
    • Journal of Ocean Engineering and Technology
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    • v.22 no.4
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    • pp.78-83
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    • 2008
  • In recent years, small boats used for marine leisure have been steadily increasing because of the increase in national income and the desire for marine leisure. But the repair of such small boats in dry dock has pointed out many faults in small FRP-shipbuilding in terms if workspace and manpower. Lifting a boat from the water to land is done with a crane or by hand using a sling around the bottom of the boat. But dry dock work is limited by the scale of the boat, which corresponds to the crane capacity, with carelessness making it possible to capsize a boat and endanger life. The purpose of this study was the development of a marine docking system that would improve economical efficiency and safety, for which we carried out concept design, model tests, structural analysis, etc.

Scaling analysis of the pressure suppression containment test facility for the small pressurized water reactor

  • Liu, Xinxing;Qi, Xiangjie;Zhang, Nan;Meng, Zhaoming;Sun, Zhongning
    • Nuclear Engineering and Technology
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    • v.53 no.3
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    • pp.793-803
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    • 2021
  • The small PWR has been paid more and more attention due to its diversity of application and flexibility in the site selection. However, the large core power density, the small containment space and the rapid accident progress characteristics make it difficult to control the containment pressure like the traditional PWR during the LOCA. The pressure suppression system has been used by the BWR since the early design, which is a suitable technique that can be applied to the small PWR. Since the configuration and operating conditions are different from the BWR, the pressure suppression system should be redesigned for the small PWR. Conducting the experiments on the scale down test facility is a good choice to reproduce the prototypical phenomena in the test facility, which is both economical and reasonable. A systematic scaling method referring to the H2TS method was proposed to determine the geometrical and thermohydraulic parameters of the pressure suppression containment response test facility for the small PWR conceptual design. The containment and the pressure suppression system related thermohydraulic phenomena were analyzed with top-down and bottom-up scaling methods. A set of the scaling criteria were obtained, through which the main parameters of the test facility can be determined.

Determinant Factors for the Apartment Unit Prices of Large Scale Apartment Complexes over 1,000 Households in Seoul Metropolitan Area (서울시 1,000세대 이상 대규모 아파트단지의 아파트가격 결정요인에 관한 연구)

  • Kim, Kwang-Young;Ahn, Jeong-Keun
    • Journal of the Korean housing association
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    • v.21 no.6
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    • pp.81-90
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    • 2010
  • The existing most studies on the apartment sales prices have been limited to relatively small size apartment complexes and have not categorized the apartment complexes based on the number of households. Some of them uses the apartment-related indices such as regional value estimates, sales unit price, and view right values. In the case of Seoul Metropolitan Area, the size of apartment complex has been growing to the level of large complex over more than 1,000 households through new town development, redevelopment and reconstruction. People prefers to choose a large scale complex instead of small complex based on their perception that a large scale apartment complex provides more conveniences in living. The result of this analysis revealed that the variables chosen as important determinants of the hedonic price model for large scale apartment complexes were square meters of apartment unit, rent/price ratio, number of bays, distance to the nearest subway station, and heating system method. This means that the sales price of apartment unit will be higher as the square meters of apartment unit increase, as the rent/price ratio decreases, as the distance to the nearest subway station increases, and as the number of bays increase.

Virtual Home Training - Virtual Reality Small Scale Rehabilitation System (가상 홈 트레이닝 - 가상현실 기반 소근육 재활 시스템)

  • Yu, Gyeongho;Kim, Hae-Ji;Kim, Han-Seob;Lee, Jieun
    • Journal of the Korea Computer Graphics Society
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    • v.24 no.3
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    • pp.93-100
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    • 2018
  • This paper proposes a small-scale rehabilitation system that allows stroke patients to perform daily rehabilitation training in a virtual home. Stroke patients have limited activities of daily living due to paralysis, and there are many rehabilitation exercises for them to reproduce activities that take place in the house, such as turning lights on and off, door opening and closing, gas valve locking. In this paper, we have implemented a virtual home with the above mentioned daily rehabilitation training elements, by using virtual reality technology. We use Leap Motion, a hand motion recognition device, for rehabilitation of hands and fingers. It is expected that stroke patients can rehabilitate small muscles without having to visit the clinic with uncomfortable body, and will be able to get interesting rehabilitation training by avoiding monotony of existing rehabilitation tools.

Summary of the engine system research using small jet engines in JAXA

  • Futamura, Hisao;Okai, Keiichi;Koh, Masaharu;Mizuno, Takuya;Yanagi, Ryoji
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2004.03a
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    • pp.763-767
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    • 2004
  • A possible and practical engine system research method is proposed. Varieties of objectives of the engine component and system technology developments are fulfilled by the small scale rig and engine demonstration. Some research applications of small jet engines in National Aerospace Laboratory of Japan (NAL) are presented together with historical overview.

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Automatic T-P Coagulation Control System using an EC in the MSBR Process - Full Scale Study - (MSBR 공정에서 전기전도도를 이용한 인 제거 자동제어시스템 - 현장 적용 중심 -)

  • Jang, Hee-seon;Lee, Ho-sik
    • Journal of Korean Society on Water Environment
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    • v.33 no.1
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    • pp.90-96
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    • 2017
  • Many sewage treatment plants have applied the advanced technology of chemical coagulant system to remove phosporus in Korea. However there are some problems for the injection of optimum coagulant dosage. In order to solve these problems, the research related to the more cost-effective automatic total phosphorus coagulation control system using an EC(Electrical Conductivity) have been in progress. This study was conducted by the same process and operation method as the Lab-scale for public small town sewage treatment plant. First, it confirmed the correlation among the EC, PO4-P and coagulant dosage in the Lab-scale MSBR(Membrane Sequencing Batch Reactor) process. Next, it analyzed that correlation coefficient of EC and the coagulant dosage was 0.92 in the Full-scale MSBR process. As a result, not only T-P removal efficiency was doubled but also it satisfied the effluent water quality standard in a stable manner. In addition, by applying the automatic control system using the EC, compared to the fixed coagulant injection system the coagulant dosage could be reduced by 28%.