• 제목/요약/키워드: U-Value

검색결과 2,052건 처리시간 0.034초

해성점토의 물리적 특성과 압축지수의 상관성 (Relationship Between Physical Properties and Compression Index for Marine Clay)

  • 김동후;김기웅;백영식
    • 한국지반공학회논문집
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    • 제19권6호
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    • pp.371-378
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    • 2003
  • 한반도 서, 남해안 해성점토에 대하여 초기간극비와 자연함수비 및 액성한계의 물리적 특성과 압축지수와의 상관성을 규명하기 위해 비교적 신뢰성이 크다고 볼 수 있는 대형 항만 공사용 최근자료를 분석하였다. 시료교란의 정도를 분석하기 위하여 각 표본별 실내압밀시험을 실시하고 Schmertmann이 제안한 방법으로 보정하여 수정압축지수를 산정하였다. 또한 이들 자료를 토대로 실내압밀시험으로부터 얻어진 압축지수를 경험적 방법에 의하여 보정한 후 현장 처녀압축곡선과의 관계를 분석하고, 단순회귀분석, 다중회귀분석 및 비선형 회귀분석을 실시하여 최적의 회귀모델을 구한 후 해성점토에 적용할 수 있는 토질특성과 시료교란의 영향을 고려한 압축지수와의 상관 관계식을 제안하였다. 분석 결과, 시료교란의 영향을 경험적 방법으로 평가해 본 결과 현장 압축지수는 실험실 압축지수의 1.16배정도 크게 평가되었다. 해성점토의 물리적 특성과 압축지수의 상관성에 대한 최적의 회귀모형은 토질정수의 누승식 또는 지수승식 형태의 비선형회귀식이 가장 적합한 것으로 나타났다. 또한, 설계 및 실무에 보다 쉽게 적용할 수 있도록 하기 위하여 선형관계식을 사용하는 경우에는 압축지수의 상관식을 물성치의 구간에 따라 구분하여 사용하는 것이 바람직하다.

건물일체형 태양광발전 시스템 성능평가 프로그램 개발 (The Development of Performance Evaluation Program of Building Integrated Photovoltaic System)

  • 김법전;박재완;윤종호;신우철
    • KIEAE Journal
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    • 제15권4호
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    • pp.85-90
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    • 2015
  • Purpose: In design and planning Building Integrated Photovoltaic(BIPV) system can reduce cost by replacing building facade as construction material such as roofs, outer walls and windows as well as generating electricity. BIPV system should be applied at the early stage of architectural design. However, it is hard to decide whether using BIPV system or not for architects and builders who are not professional at BIPV system because performance of system is considerably influenced by types of module, installation position, installation methods and so on. It is also hard for experts because commercialized analytical program of photovoltaic systems is too complicated to use and domestic meteorological data is limited to partial areas. Therefore, we need evaluation program of BIPV system which can easily but accurately interpret generating performance and evaluate validity of BIPV system at the early stage of architectural design even for inexpert. Method: In this study, we collected meteorological data of domestic major region and analyzed generation characteristic of BIPV system by using PVsyst(commercialized software) in accordance with regions, types of solar module, place and methods of installation and so on. Based on this data, we developed performance evaluation program of BIPV system named BIPV-Pro, through multiple regression analysis and evaluated its validity. Result: When comparing predictive value of annual average PR and annual electricity production of BIPV-Pro an that of PVsyst, each of root mean square error was 0.01897 and 123.9.

The verification about possibility of introducing Window to Floor Ratio as design index for building energy performance

  • Choi, Won-Ki;Lee, Yong-Jun;Lee, Hyun-Soo;Eom, Jae-Yong;Lee, Chung-Kook
    • KIEAE Journal
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    • 제17권1호
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    • pp.23-28
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    • 2017
  • Purpose: Many design index that are using in planning phase have been developed. The most popular things among them are Window to Wall Ratio and Surface to Volume Ratio. However there are some limits. Window to Wall Ratio cannot consider building size and Surface to Volume Ratio cannot do Window to Wall Ratio. Accordingly, in this paper, the Window to Floor Ratio was proposed that it can be considered both building size and Window to Wall Ratio. And analyzed correlation of energy demand. Method: For the test, 16 modules with the size of $6m{\times}6m{\times}4m$ were used to make 35 models with the same volume. The simulation was conducted to 945 cases using the window-to-wall ratio of 30, 50 and 70 % in three areas such as Seoul, Gwangju and Jeju and three kinds of windows. And IES_VE was used. Result: The findings above show that the Window to Floor Ratio that can be considered both building size and Window area have to become as design index. It was found out that design criteria with SHGC is necessary, not with the thermal performance (U-value). It is needed to additional analysis about residential building and the effect of 24-hours heating and cooling condition. It plans to carry out research to establish design indicators for climatic conditions in the country and building applications.

아파트 홈네트워크 시스템 적용실태 조사연구 (Analyzing Home Network System Adaptation Status in Apartments)

  • 이선아;장경문;김재준
    • 한국건설관리학회:학술대회논문집
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    • 한국건설관리학회 2004년도 제5회 정기학술발표대회 논문집
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    • pp.571-574
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    • 2004
  • 최근 건설업체는 주택상품 기획시 홈네트워크를 차별화 요소로 사용하고 있으나 공급자로서의 역할만 하고 있을 뿐 앞으로 창출될 거대한 규모의 홈네트워크 시장에 대한 적절한 수익모델을 발견하지 못하고 있는 실정이다. 관련업계에서는 유비쿼터스(Ubiquitous)시대를 대비하여 국가성장동력으로 삼으려는 정부의 정책하에 관련 가전, 통신, 방송업계의 시장선점을 위한 각축이 진행중이다 한편 인구구조 및 라이프스타일의 변화 등으로 인해 디지털화된 주거환경에 대한 소비자의 요구도 높아지고 있다 그러나 현재 거주자들에게 제공되고 있는 대부분의 홈디지털 서비스는 정책적 뒷받침의 부족과 분양가상승 우려 등으로 초보적인 수준에 머물러 있는 것으로 조사되었다. 미래주거환경을 선도해야할 건설사들에게 고객특성별 수요분석을 통한 품목 개발과 적극적인 수용의지가 요구되고 있다.

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운송인(運送人)의 손해배상책임제한(損害賠償責任制限)에 관한 역사적(歷史的) 고찰(考察) (A Historical Analysis on the Limitation of Carriers' Liability)

  • 오수근
    • 항공우주정책ㆍ법학회지
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    • 제5권
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    • pp.171-205
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    • 1993
  • On the contrary to the general principle of private law, carriers' liability for passengers and cargo owners have been quantatively limited in some cases. The author traces the rule of liability limitation in the law of Korea and United States to verify two hypotheses. The first hypothesis is that the rule of liability limitation has been introduced to motivate investment when new technology with high risk has been adopted in business. The second hypothesis is that the rule of liability limitation can be maintained only when damages have been fully compensated. The former is a necessary condition for liability limation, and the latter sufficient condition. There are strong evidences for the first hypothesis. Navigation or aviation, artificial satellite lauching, urban transportation system are good examples. The second hypothesis is supported by the fact that there have been continuous controversies on the Warsaw System, including the failure of ratification of Montreal Additional Protocols No.3 & 4 by the U.S. Senate and voluntary removal of liability limitation by the Japanese airline companies. Loss of cargo can be compensated fully, but damages from personal injury and death not. The value of human body and life is not easy to be estimated. Passengers, moreover, do not usually buy insurance for accidents in travel. Passengers do not accept insurance premium as the cost of being whole and alive. They do not accept accident rates realistically. They have no bargaining power in dealing with insurers. The rule of liability limitation in personal losses would not be supported in future because damages have not fully compensated.

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대역확산 시스템용 병렬 상관기를 위한 저 전력 누적기 설계 (Design of a Low Power Consumption Accumulator for Parallel Correlators in Spread Spectrum Systems)

  • 류근장;정정화
    • 전자공학회논문지C
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    • 제36C권12호
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    • pp.27-35
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    • 1999
  • 일반적으로 병렬 상관기 (correlator)는 대역확산 시스템의 전체 전력소모 중 많은 부분을 차지하며, 그의 주요 원인은 다수의 누적기에서 발생하는 전력소모에 기인한다. 본 논문에서는 이러한 병렬 상관기에 적합한 저 전력 소모 누적기를 제안한다. 제안된 누적기는 입력되는 데이터 값의 1의 개수를 비트별로 카운트하고 누적 완료 시에만 카운터 값들에 웨이트를 부가하여 가산함으로써 저 전력 동작을 구현한다. 제안된 누적기는 Cadence사의 Verilog-XL로 설계되고, 0.6u의 Standard Cell Library를 사용하여 Synopsys사의 Design Compiler로 로직 합성이 수행되었다. 시스템의 전력 시뮬레이션은 Apic사의 Powermill을 사용하였다. 시뮬레이션 결과, 제안된 누적기의 전력 소모는 기존의 누적기보다 22%까지 감소되었으며, 또한 최대 동작 주파수는 323%까지 향상되었다. 제안된 누적기로 구성된 병렬 상관기의 전력소모는 기존의 누적기를 사용한 병렬 상관기에 비교해서 22% 감소하였고, 기존의 수동병렬 상관기에 비교해서 43% 감소하였다.

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The effects of dentin bonding agent formulas on their polymerization quality, and together with tooth tissues on their microleakage and shear bond strength: an explorative 3-step experiment

  • Erfan, Mohmmad;Jafarzadeh-Kashi, Tahereh Sadat;Ghadiri, Malihe;Rakhshan, Vahid
    • The Journal of Advanced Prosthodontics
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    • 제6권5호
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    • pp.333-345
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    • 2014
  • PURPOSE. Bonding agents (BA) are the crucial weak link of composite restorations. Since the commercial materials' compositions are not disclosed, studies to formulize the optimum ratios of different components are of value. The aim of this study was to find a proper formula of BAs. MATERIALS AND METHODS. This explorative experimental in vitro study was composed of 4 different sets of extensive experiments. A commercial BA and 7 experimental formulas were compared in terms of degree of conversion (5 experimental formulas), shear bond strength, mode of failure, and microleakage (3 experimental formulas). Statistical analyses were performed (${\alpha}$=.05). The DC of selected formula was tested one year later. RESULTS. The two-way ANOVA indicated a significant difference between the shear bond strength (SBS) of two tissues (dentin vs. enamel, P=.0001) in a way that dentinal bonds were weaker. However, there was no difference between the four materials (P=.283). The adhesive mode of failure was predominant in all groups. No differences between the microleakage of the four materials at occlusal (P=.788) or gingival (P=.508) sites were detected (Kruskal-Wallis). The Mann-Whitney U test showed a significant difference between the microleakage of all materials (3 experimental formulas and a commercial material) together at the occlusal site versus the gingival site (P=.041). CONCLUSION. A formula with 62% bisphenol A-glycidyl methacrylate (Bis-GMA), 37% hydroxy ethyl methacrylate (HEMA), 0.3% camphorquinone (CQ), and 0.7% dimethyl-para-toluidine (DMPT) seems a proper formula for mass production. The microleakage and SBS might be respectively higher and lower on dentin compared to enamel.

Evaluation of the reproducibility of various abutments using a blue light model scanner

  • Kim, Dong-Yeon;Lee, Kyung-Eun;Jeon, Jin-Hun;Kim, Ji-Hwan;Kim, Woong-Chul
    • The Journal of Advanced Prosthodontics
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    • 제10권4호
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    • pp.328-334
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    • 2018
  • PURPOSE. To evaluate the reproducibility of scan-based abutments using a blue light model scanner. MATERIALS AND METHODS. A wax cast abutment die was fabricated, and a silicone impression was prepared using a silicone material. Nine study dies were constructed using the prepared duplicable silicone, and the first was used as a reference. These dies were classified into three groups and scanned using a blue light model scanner. The first three-dimensional (3D) data set was obtained by scanning eight dies separately in the first group. The second 3D data set was acquired when four dies were placed together in the scanner and scanned twice in the second group. Finally, the third 3D data set was obtained when eight dies were placed together in the scanner and scanned once. These data were then used to define the data value using third-dimension software. All the data were then analyzed using the non-parametric Kruskal-Wallis H test (${\alpha}=.05$) and the post-hoc Mann-Whitney U-test with Bonferroni's correction (${\alpha}=.017$). RESULTS. The means and standard deviations of the eight dies together were larger than those of the four dies together and of the individual die. Moreover, significant differences were observed among the three groups (P<.05). CONCLUSION. With larger numbers of abutments scanned together, the scan becomes more inaccurate and loses reproducibility. Therefore, scans of smaller numbers of abutments are recommended to ensure better results.

Jean Michel Basquiat의 그래피티(Graffiti)를 응용한 패션페인팅 (The Application of Jean Michel Basquiat's Graffiti to Fashion Painting)

  • 장애란;고은숙
    • 대한가정학회지
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    • 제44권6호
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    • pp.23-34
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    • 2006
  • Graffiti has been recognized as an art form since the influence of free, black culture and Neo-Expressionism in the 1980s, though Graffiti remains the subject of controversy both inside and outside the school Modem Art. Jean Michel Basquiat is the most famous Graffiti artist of the '80. He was regarded as the genius and star of American art, leaving a lot of experimental and creative works during his short, 9-year, creative period. In his works, Basquiat well expressed the isolated and dark shadows in the U.S., the pursuit of self identification, the purpose of expression and the epochally social phenomenon. The purpose of this study is to investigate the application of Jean Michel Basquiat's Graffiti to fashion painting. To achieve this purpose, we present a lot of fashion painting works which apply Jean Michel Basquiat's Graffiti by focusing on autographic experience, racialism, cartoon themes, monely value, and anatomical death in the characteristics of Basquiat's works. Through this process, we can express and apply Basquiat's Graffiti to fashion painting by analogizing the themes and modeling the methods of his works, such as childish and simple features, intentionally wrong spellings and sentences, and symbols of death including skeletons, intestines, bones and teeth. In addition, Basquiat's techniques are examined in this study, including the representational handling of a brush, primitive and strong colors, and maximized shape. This study found that fashion painting can juxtaposes art and fashion by expressing Jean Michel Basquiats' Graffiti.

우즈베키스탄 Maidanak 천문대 Fairchild 486 CCD의 기본적인 특성 (CHARACTERISTICS OF THE FAIRCHILD 486 CCD AT MAIDANAK ASTRONOMICAL OBSERVATORY IN UZBEKISTAN)

  • 임범두;성환경
    • 천문학논총
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    • 제23권1호
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    • pp.1-12
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    • 2008
  • Understanding of the basic characteristics of an astronomical instrument is a prerequisite to obtaining reliable data from the instrument. We have analyzed more than 1,000 calibration images from the Fairchild 486 CCD (hereafter the Maidanak 4k CCD system) attached to the AZT-22 1.5m telescope at Maidanak Astronomical Observatory in Uzbekistan. The Maidanak 4k CCD system supports three readout modes through 1, 2, or 4 amplifiers. In most cases observers use 4-amplifier readout mode to save time. We have tested the stability and seasonal variation of zero levels and confirm that two quadrants of the images (Amp 1 & 2) show no appreciable seasonal variation. but the other two quadrants (Amp 3 & Amp 4) show an evident seasonal variation in the bias level. The Cryo Tiger, the cooling system used at the Maidanak 4k CCD system, maintains the CCD temperature at -108'E, and effectively suppresses the dark electrons. The mean value versus the variance plot of the flat images does not show the expected relation for an ideal Poisson noise distribution and this is attributed to the large variation in quantum efficiency between different pixels. In addition, we confirm that there is no appreciable difference in gain between readout amplifiers, but there is a large variation in quantum efficiency across CCD chip especially in U. Due to the finite length of shutter opening and closing time, the effective exposure time varies across the science images. We introduce two parameters to quantify the effect of this uneven illumination and present a method to remove these effects. We also present a method to remove the interference patterns appearing in the images obtained with longer wavelength filters and investigate the spatial variation of the point spread function.