• 제목/요약/키워드: Covering methods

검색결과 533건 처리시간 0.028초

사각형네트워크 단층래티스돔의 좌굴특성 -실험과 이론과의 비교- (Buckling Characteristics of Rigidly-jointed Single-Layer Latticed Domes with Square Network -Comparison between Experiment and Analysis-)

  • 정환목
    • 한국강구조학회 논문집
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    • 제10권3호통권36호
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    • pp.463-472
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    • 1998
  • 본 논문의 목적은 4각형네트워크 패턴을 가지는 단층래티스돔의 좌굴특성을 실험과 이론을 통하여 검토하고, 나아가 4각형 네트워크 단층돔에 대한 신뢰할 수 있는 이론해석법을 개발하기 위한 기초연구를 하는데 그 목적이 있다. 이론해석은 야마다의 연속체치환법과 유한요소법에 의한 프레임해석법으로 한다. 원주방향에 대한 불균일한 강성과 지붕재료의 강성이 돔전체 좌굴특성에 미치는 영향을 검토한다. 이론과 실험에 의한 결과는 불균일한 강성을 가지거나 또는 강성을 갖는 지붕재료를 사용하는 다양한 종류의 단층래티스돔에 대한 일반적인 이론해석법을 개발하기 위한 기초자료로 활용될 것이다.

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Resistance Reduction of a High Speed Small Boat by Air Lubrication

  • Jang Jin-Ho;Kim Hyo-Chul
    • Journal of Ship and Ocean Technology
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    • 제10권1호
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    • pp.1-9
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    • 2006
  • The resistance reduction by an air lubrication effect of a large air cavity covering the hull bottom surface and the similarity relations involved have been investigated with a series of towing tank tests of three geometrically similar models. The test results of geometrically similar models have indicated that a large air cavity was formed beneath the bottom having a backward-facing step by artificially supplying air is effective for resistance reduction. The areas of air cavity and the required flow rates of air are directly related to the effective wetted surface area. The traditional extrapolation methods seem to be applicable to the estimation of the resistance in the tested range if corrections are made to account the changes in the frictional resistance caused by the changes in the effective wetted surface area. To investigate the effectiveness of air lubrication in improving the resistance performance of a practical ship, a small test boat having a backward-facing step under its bottom has been manufactured and speed trials in a river have been performed. Air has been supplied artificially into the downstream region of the bottom step to form a large air cavity covering the bottom surface. The results have confirmed the practical applicability of air lubrication for the resistance reduction of a small high-speed boat.

Polypeptide계 인공 피부의 합성과 특성 (Synthesis and Characterization of Artificial Skin based on Polypeptides)

  • 김선정;민동선;김계용
    • 대한의용생체공학회:의공학회지
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    • 제8권1호
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    • pp.87-92
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    • 1987
  • In order to evaluate the artificial skin for burn would covering materials, copoly(N. carbobenzoxy-L-Iysine-L-leucine)s were prepared by Ipolymerization of N - carbobenzoxy-L- I sine anhydride and L-leucine anhydride in homogeneous solvents using triethylamine as an initiator. The synthetic polypeptides and the oxter type polyurethane(PV)of medical grade were used as the sheet type membranes were prepared ; monolayer membrances were composed of only the polypeptides, bilayer membranes and blend membranes were controlled by composition of the polypeptides and PU. Test of the swelling degree, mechanical tensile strength, elongation, oxygen permeability, water-vapor loss and In vitro degradation treated by pretense TV of samples of artificial skin were measured by adequate methods so as to mechanical, physincal characterization and biodegradation. As a result, all the values of samples were found to be similar to desired value of skin which was nature. The Artificial skin based on polypeptides can be considered as ideal burn wound covering materials.

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플랑드르 회화에 표현된 벽걸이 직물의 발달 배경과 특징에 관한 연구 (A Study on the Background and Characteristics of Textile Wallcovering in Flemish Painting)

  • 이준한;김선미
    • 패션비즈니스
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    • 제24권4호
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    • pp.19-29
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    • 2020
  • The purpose of this study was to investigate Renaissance wall-covering fabrics through Flemish paintings, that provides the details of the origin and development of background of modern wallcovering. The methods of the study are as follows. First, the background of textile development of Flanders in the 14th to 16th centuries were examined through a prior study. Second, the shape and use of wallcoverings in paintings painted during that time were analyzed and the process of changing to modern forms was studied. The residential environment with many stone buildings in relatively humid and cold weather created a need for decorative fabrics. Back then, the wool and flax fabric were not allowed to be worn on the body, so the materials were used for the development of interior fabrics. The characteristics of wall covering in Flemish paint can be summarized with movable, allegory, and decoration. Movable stems from the arrival of the emerging aristocrats of Flanders, who had enormous commercial trade and carried decorative fabrics; the mobility has become an allegory in reality as the royal and aristocratic use of wall-decorated fabrics is the symbol of authority. In addition, unlike Italy, where silk was procured from the East, fabrics manufactured using flax and wool were not suitable for clothing in terms of religion and practicality and were used to decorate walls.

대학생의 건강정보이해능력과 건강증진행동(식습관, 신체활동과 스트레스)과의 관련성 (Association Between Health Literacy and Health Promoting Behavior (Eating Habits, Physical Activity, and Stress) of University Students)

  • 김윤선
    • 대한지역사회영양학회지
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    • 제27권2호
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    • pp.94-104
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    • 2022
  • Objectives: This study attempted to examine the association between health literacy and health-promoting behavior, and identify the major variables that affect the health-promoting behavior of university students. Methods: This was a descriptive correlation study that identified the degree of health literacy and health-promoting behavior of 248 university students (119 male and 129 female) and examined the correlation between the two and factors influencing them. The questionnaire covering health literacy comprised 66 questions, and that for health-promoting behavior comprised 10 questions covering eating habits, 3 questions about physical activity, and 10 questions involving stress. Results: The score for health literacy was 41.56 ± 18.38 out of 66 points, and that for health-promoting behavior was 65.27 ± 11.21 points (27.61 ± 6.72 points for eating habits, 7.23 ± 2.56 points for physical activity, and 30.44 ± 5.61 points for stress). Health literacy and health-promoting behavior had a significant positive correlation (r = 0.175, P < 0.01). The perceived health status (β = 0.391, P < 0.001) was the most important variable in health-promoting behavior, followed by health literacy (β = 0.236, P < 0.001). Conclusions: It is necessary to develop a systematic educational strategy and implement educational programs to improve health literacy as well as encourage health-promoting behavior and thus increase the perceived health levels of university students.

Considerations for the Management of Medial Orbital Wall Blowout Fracture

  • Kim, Yong-Ha;Park, Youngsoo;Chung, Kyu Jin
    • Archives of Plastic Surgery
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    • 제43권3호
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    • pp.229-236
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    • 2016
  • Recently, diagnoses of and operations for medial orbital blowout fracture have increased because of the development of imaging technology. In this article, the authors review the literature, and overview the accumulated knowledge about the orbital anatomy, fracture mechanisms, surgical approaches, reconstruction materials, and surgical methods. In terms of surgical approaches, transcaruncular, transcutaneous, and transnasal endoscopic approaches are discussed. Reconstruction methods including onlay covering, inlay implantation, and repositioning methods are also discussed. Consideration and understanding of these should lead to more optimal outcomes.

Identifying Tools for Systemic Teaching Analysis in Higher Education

  • ROH, Hyelan;CHOI, Mina;SEO, Youn-Kyung
    • Educational Technology International
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    • 제8권2호
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    • pp.73-91
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    • 2007
  • The purpose of this study is to explore tools for systemic and integrated teaching analysis in recognition of problems derived from the existing teaching analysis which have been held fragmentarily and temporarily. In order to do so, a teaching analysis tools is identified by examining the current services of video-taping and analysis, which are the most representative teaching analysis methods among the Centers for Teaching and Learning (CTLs) in Korea, and by redefining teaching analysis through literature review. A teaching analysis is to be done to challenge teachers to change and grow by providing a motive to reflect on the act of teaching and carry out improvements, and it has to be held covering the general act of teaching and examined through diverse methods in systemic and multidimensional perspectives over a full period of teaching. In this study, an act of teaching is examined in four areas: planning, teaching skill, evaluation and reflection, and teaching analysis frameworks according to an act of teaching are suggested by periods of before, during, and after a term. Teaching analysis methods are also suggested by the frameworks.

표면마감방법과 볕쪼임이 숙성중 표층 고추장 품질에 미치는 영향 (Effect of Surface finishing method and sunning on top layer Kochuiang Quality during Aging)

  • 김중만;송현주;양희천
    • 한국식생활문화학회지
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    • 제8권3호
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    • pp.249-255
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    • 1993
  • 고추장을 직립성 용기에 담아 숙성보관시 곱이 발생하는 것을 방지하기 위하여 햇빛을 쪼여 표면을 관리하는 것이 일반적이나 이 경우 표면층 고추장이 건조되고, 적색이 흑변되고, 유동성이 상실되며, 과염도 및 이물질 오염 등으로 인하여 많은 양이 비가식화되는 문제가 있어 왔다. 숙성 보관중 표층 고추장의 악변에 의한 손실을 최소화할 수 있는 숙성 조건을 조사하기 위하여 표면을 3가지 방법(무처리, 소금뿌림, PE-film덮기)으로 처리한 후 각각 햇빛을 쪼이면서 숙성한 경우(A, B, C)와 A, B, C와 같이 처리한 후 뚜껑을 덮어 숙성(A', B', C')시키면서 15일 간격으로 수분, 염도, pH, 점도, 퍼짐성(찍음성), 색도, 곱의 발생유무를 조사 비교하였다. 2일에 1회 햇빛을 쪼이면서 120일간 숙성시킨 경우(A, B, C)곱은 발생되지 않았으나 수분함량 감소$(59%{\rightarrow}21-29%)$, 적색도 감소 내지는 흑색화$(21{\rightarrow}0-1)$, 퍼짐성 감소, 굳기 증가$(20{\;}g{\rightarrow}380{\;}g)$ 및 과염도화$(8-18%{\rightarrow}18-30%)$ 등으로 많은 양이 비가식화되는 문제가 발생하였다. 반면 뚜껑을 덮어 숙성시킨 경우 적색도, 염도, 퍼짐성, 굳기는 양호하게 유지되었으나 PE-film을 사용한 경우를 제외하고 곱이 많이 발생되어 PE-film을 덮어 숙성시키는 것이 고추장 표면을 건전하게 관리하는데 효과적인 방법으로 확인되었다.

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쓰레기매립지의 환경복원 (A Review on Environmental Restoration of the Waste Landfills)

  • 김기대;이은주
    • 한국환경복원기술학회지
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    • 제6권6호
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    • pp.56-71
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    • 2003
  • Waste landfills have been the center of environmental problems and they must be restored due to environmental pollution, disgusting landscape, and cost of management. It is suggested that they be recycled urban space as cities expand. Specially, nonsanitary waste landfills which have no pollution prevention facilities cause serious problems. Restoring the landfills as parks and golf courses, so on makes more benefits because of cheap use land, closeness to urban area, flat topography applicable to parks and golf courses, and high land values after restoration and the changes to local recreation sites. Restoration of waste landfills is a complex, costly, and interdisciplinary work. But, the waste landfill is a manmade ecosystem. Control, restoration and postmanagement of waste landfills are very important problems. The role of vegetation prevents soil erosion, reduces soil water storage, and obstructs leachate seepage. Early restoration makes derelict lands into man park artificially geared to soil, vegetation, landforms and hydrology. But, Ideal restoration is to make stable ecosystem nature-friendly and compatible with surrounding landscape without more management. Landscape is structured hierarchically with patches and stands as small components and forms forest as large components. Therefore, landscape formation of the waste landfills needs much restoration process. There are many ecological restoration techniques for the waste landfills. Those are divided into artificial and natural methods. The artificial method is anthropogenic plantings while the natural method is to trigger and use succession processes. The most important thing in the restoration of waste landfills is to consider the final restoration objectives of each waste landfill. According to these objectives, the depth of covering layer, planting degree, and structural design should be determined. The effective restoration methods should be selected of artificial and natural options.

빅데이터 보안 분야의 연구동향 분석 (A Review of Research on Big Data Security)

  • 박서기;황경태
    • 정보화정책
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    • 제23권1호
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    • pp.3-19
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    • 2016
  • 본 연구의 목적은 빅데이터 보안 분야의 기존 연구를 분석하고, 향후 연구 방향을 모색하는 것이다. 이를 위해 국내외의 총62편의 논문을 식별하여, 발간년도, 게재 매체, 전반적인 연구접근 방법, 세부적 연구 방법, 연구 주제 등을 분석하였다. 분석 결과, 빅데이터 보안 연구는 매우 초기 단계로서, 비실증 연구가 압도적인 비중을 차지하고 있고, 관련 개념/기법에 대한 이해를 해나가는 과정으로서 기술-관리-통합의 단계로 진화한 정보보안 분야의 연구 동향에 동조하여 기술적인 연구가 주로 진행되고 있다. 연구 주제 측면에서도 빅데이터 보안에 대한 전반적인 이슈를 다룬 총론적인 연구들이 보안 구현 방법론, 분야별 이슈 등의 각론적 연구에 비해 높은 비중을 나타내는 등 초기 단계의 모습을 나타내고 있다. 향후 유망한 연구 분야로는 빅데이터 보안에 대한 전반적인 프레임워크 수립, 업종별 빅데이터 보안에 대한 연구, 빅데이터 보안 관련 정부 정책 분석 등을 들 수 있다. 빅데이터 보안 분야의 연구는 본격적으로 시작된 지 얼마 되지 않아, 연구 결과가 상대적으로 매우 부족한 편이다. 앞으로 다양한 관점에서 빅데이터 보안과 관련해 풍부한 주제를 다루는 연구가 진행되기를 기대한다.