• Title/Summary/Keyword: Reasonable alternative

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Analysis of Heat Transfer Characteristics in Soil for Development of a Geothermal Heat Exchange System (지열 열교환시스템 개발을 위한 지중 열유동 특성분석)

  • Lee Y. B.;Cho S. I.;Kang C. H.;Jung I. K.;Lee C. G.;Sung J. H.;Chung S. O.;Kim Y. B.
    • Journal of Biosystems Engineering
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    • v.30 no.3 s.110
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    • pp.185-191
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    • 2005
  • Importance of alternative energy has been increasing due to environmental issues and lack of fossil fuels. In addition, heating cost that occupies from 30 to $40\%$ of the total production cost in the protected cultivation sector in Korea needs to be reduced for profitability and global competition. But, study on geothermal energy to solve these problems has not been activated for Korean protected cultivation. This study was conducted to develop an optimized geothermal exchange system through fundamental test of heat transfer characteristics in soil such as thermal diffusivity, changes in soil temperature during heating and cooling operations, and restorations of soil temperature after the heater was fumed off, These issues were investigated using computer simulation for different depths. The simulated characteristics were evaluated through controlled tests. Simulated characteristics of heat transfer in the soil at different depths showed a reasonable agreement with the results of the controlled tests. All of computer simulation and controlled tests, soil temperatures changed at 10cm and 20cm distance from pipe. but don't change at more than 30cm distance. It means that distances of heat transfer of the soil ranged from 20 to 30cm a day. Based on these results, the optimum spacing between adjacent heat exchange pipes and the pitch were selected as 50 and 40cm, respectively.

Modified Essex-Lopresti Reduction for the Displaced Intra-articular Calcaneal Fractures (전위된 관절 내 종골 골절에 대한 Essex-Lopresti 변형 정복술)

  • Kwak, Kyoung-Duck;Cho, Hyoun-Oh;Lim, Dae-Hwan;Ahn, Sang-Min;Jang, Jae-Ho
    • Journal of Korean Foot and Ankle Society
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    • v.7 no.1
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    • pp.109-114
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    • 2003
  • Purpose: The purpose of this study is to evaluate the effectiveness and indications of the modified Essex-Lopresti reduction in calcaneal fractures. Materials and Methods: We reviewed retrospectively 41 cases of displaced intraarticular calcaneal fractures. The fracture was reduced with Essex-Lopresti technique with modification in compression of the lateral wall with the specially designed compression device instead of the operator's hands. We evaluated the results of treatment by AOFAS scale and the radiographic parameters including the Bohler's angle, calcaneal width, calcaneofibular distance and the congruency of the posterior facet. Results: Boler's angle was restored from 11 to 29.6 degrees on average, heel width was reduced to 112% of contralateral value, the calcaneofibular gap was restored up to 87.9% of contralateral side, and the articular surface of the posterior facet was restored less than 2 mm of step off and less than 2 mm of gap. AOFAS scale averaged 87 points. The quality of reduction was best in Sander's type II fractures. Small sized fragments in type III fractures could not be reduced. The results were better when the reductions were performed within 24 hours of injury. Conclusion: The modified Essex-Lopresti reduction was less invasive, easy to perform, and the results of treatment were similar to those of open reduction; it seemed to be a reasonable alternative for the selected intraarticular calcaneal fractures.

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A Study on Triangulated Irregular Network Generation Method for GSIS (지형공간정보체계의 이용을 위한 불규칙삼각망 생성기법에 관한 연구)

  • 유복모;장지원;윤정학
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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    • v.12 no.2
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    • pp.209-218
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    • 1994
  • This study aims to generate triangulated irregular network in a form of digital terrain model which is being increasingly used. In general, grid digital elevation model and triangulated irregular network are reasonable units for solving terrain problems. But, triangulated irregular network is an efficient alternative to grid digital elevation model because of their efficiency in storing data and their convenient data structure for accommodating irregularly spaced elevation data. Various methods represented for extracting triangulated irregular networks from grid digital elevation model, and then algorithm that get accurate results for triangulation with their data set was introduced. The new approach for triangulation in this study uses the Elevation and Changeable Distance criterion, and adding interpolation points and restricted constraint lines can generate triangulated irregular network which is more close to real surface. This made database efficient construction and could be used for many applications of geo-spatial information system.

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Antimicrobial Agent from Schima wallichii ssp. liukiuensis against Candida spp. (Schima wallichii ssp. Liukiuensis 추출물 Sterol Glycoside의 Candida spp.에 대한 항균활성)

  • Shin, Kuem;Min, Ji-Yun;Kang, Seung-Mi;Park, Dong-Jin;Song, Hyun-Jin;Kwon, Oh-Woong;Yang, Jae-Kyung;Karigar, Chandrakant S.;Choi, Myung-Suk
    • Korean Journal of Medicinal Crop Science
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    • v.17 no.1
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    • pp.61-67
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    • 2009
  • This study carried out development of a natural antimicrobial agent from Schima wallichii ssp. liukiuensis. Compound I exhibiting potent antimicrobial activity against Candida spp. was isolated from the methanol extracts of Schima wallichii ssp. liukiuensis. The structure of I identified as a sterol glycoside consisted of a trisaccharide and ${\alpha}_1$-sitosterol. Trisaccharide composed of L-rhamnose, D-galactose and D-glucose residues. The antimicrobial activity of I was selective on yeast rather than bacteria or other fungi. Compound I was demonstrated to be ineffective against toxicity to mouse liver cells where as protective to human dermal fibroblast cells at low concentrations. Thus, it is reasonable to expect a sterol glycoside (I) as a valuable alternative for synthetic antifungal.

A Study on the Mapping of Wind Resource using Vegetation Index Technique at North East Area in Jeju Island (영상자료의 식생지수를 이용한 제주 북동부 지역의 풍력자원지도 작성에 관한 연구)

  • Byun, Ji Seon;Lee, Byung Gul;Moon, Seo Jung
    • Journal of Korean Society for Geospatial Information Science
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    • v.23 no.1
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    • pp.15-22
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    • 2015
  • To create a wind resource map, we need a contour map, a roughness map and wind data. We need a land cover map for the roughness map of these data. A land cover map represents the area showing similar characteristics after color indexing based on the scientific method. The features of land cover is classified by Remote sensing technique. In this study, we verified the application of the NDVI technique is reasonable after we created the wind resource map using roughness maps by unsupervised classification and NDVI technique. As a result, the wind resource map using the NDVI technique showed a 60% accordance rate and difference in class less than one. From the results, The NDVI technique is found alternative to create roughness maps by the unsupervised classification.

Methods for Decision making model in Apartment development projects using on Analytic Hierarchy Process (AHP기법을 이용한 공동주택 개발 사업 의사결정 평가 모델 개발)

  • Kim, Man-Jang;Lee, Jae-Seob
    • Korean Journal of Construction Engineering and Management
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    • v.9 no.5
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    • pp.95-103
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    • 2008
  • In recent years, there has been more reconstruction and redevelopment of apartments rather than efforts to consider alternative to extend the life time oh the apartments. It is essential to try to develop ways to adequately maintain and to use the apartment facilities efficiently in order to preserve earth environment and the limited resource. However, lacking research on the effects obtained through remodelling and maintenance have interfered with the vitalizing of the market. The objective of this study is to propose criterions and methods with which to evaluate adequacy of developing method. A survey was performed to investigate important evaluating methods in order to obtain advices that can smoothly progress improve apartment developing method. This study applied AHP(Analytical Hierarchy Process) methods for reasonable dependancy of developing in apartment. Through this study, the flow of apartment market is elevated to reaching the level in advanced nation.

A Critical Approach Towards Communications Deliberation: Analysis of Korea Communications Standards Commission's Proceedings (통신심의 실태에 관한 비판적 고찰: 방송통신심의위원회 산하 통신심의소위원회 회의록 분석을 중심으로)

  • Yang, Seon-Hee;Kim, Jae-Young
    • Korean journal of communication and information
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    • v.55
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    • pp.33-49
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    • 2011
  • Communications deliberation conducted by Korea Communications Standards Commission(KCSC) has been caught up in controversy in terms of the legitimacy of KCSC and its operating system. But there is few or no analysis of the state of affairs concerning the subject. This article critically examines the proceedings of KCSC in 2010 and attempts to see how true and reasonable some points of issues towards communications deliberation raised mostly by civic groups are. The study pays particular attention to unfaithful and arbitrary deliberation and broadness of the items of deliberation. By doing so, the article tries to suggest some alternative ways for improving the system of communications deliberation in Korea.

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Spatial Aggregation of Contiguous Population Distribution Grid Cells Based on Stepwise Cell Grouping Scenarios (인구분포셀 연접공간 집단화를 통한 기반시설부담구역 검토 사례연구)

  • Choei, Nae-Young
    • Journal of Korean Society for Geospatial Information Science
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    • v.18 no.4
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    • pp.51-60
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    • 2010
  • In 2008, the Development Impact Fee Zoning has been newly amended and added to the existing National Territory Planning Act. Since the beginning of 2009, many local governments nationwide started to adopt the law as a powerful tool to prepare the prescirbed masterplans for the installment of adequate infrastructure and to procure the financial resources to realize the plan. The study, in this context, tried to build gridded population data and analyzed the population cells that exceed the legal criteria of population increase rate required by the law over the case area of Sooyoung-Ri in Hwasung City. The study further probed to group the selected population cells in five specified increasing steps on which the alternative impact fee zones are built. Throughout the process, the study could properly set a reasonable impact fee zone and suggested a practical examples of the final zone specification applicable by the localities.

Comparison Study of Web Application Development Environments in Smartphone (스마트폰 상에서의 웹 응용프로그램 개발 환경 비교)

  • Lee, Go-Eun;Lee, Jong-Woo
    • The Journal of the Korea Contents Association
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    • v.10 no.12
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    • pp.155-163
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    • 2010
  • Due to the complex registration & downloading process of the native applications, and, software and their non-standardized APIs, mobile web application is now being an alternative software for smartphones. Hybrid web application, one of the types of mobile software, because develop and has reasonable performance by using the webkit engined in smartphones. It can be easily developed by using the exiting programming skill such as HTML, JavaScript and CSS. Additionally these programming techniques can be easily used in any smartphone regardless of its platforms. Most smartphones have a webkit engine or web rending engine for high performance and smooth display in web browser. Webkit is now equipped in iPhone and Android phone. In this paper, we try to find out by comparison that the various aspects of webkit APIs of iPhone & Android phone, such as screen font size, screen orientation, touch event, gesture event and their performance. We also evaluated which one is more convenient for developers when making web programs using webkit. As a result, we found out that webkit in iPhone has more excellent performance than Android.

A Study on Revising 1:1,000 Digital Topographic Maps for Seoul Metropolitan Area (서울시 1:1,000 수치지형도 갱신에 관한 연구)

  • 김윤종;박수홍;이석민;최진무
    • Spatial Information Research
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    • v.6 no.2
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    • pp.233-245
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    • 1998
  • This study focused on developing a comprehensive strategy to revise 1:1,000 digital topographic maps for Seoul metropolitan area in terms of both organizational and technical aspects. First of all, we analyze the elements of' the revision strategy in the organization domain and produce four alternatives. Of these alternatives, we suggest a best alternative which appears to be practically sound. Secondly, we review four possible map updating methodologies, paper map digitization, a partial topographic map revision method, a method utilizing scanned aerial photographs, and a method using digital orthophotos. Through a detailed technical analysis and cost analysis of each method, we suggest a reasonable map updating method. Finally, we provide a guideline for distributing 1:1,000 digital topographic maps based on the digital map distribution policy National Geography Institute.

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