• 제목/요약/키워드: conservation techniques

검색결과 440건 처리시간 0.164초

전남권역 우량 산림습원의 관속식물상 변화 및 보전방안 (Distribution and Conservation plan of Vascular Plants in Outstanding Forest Wetlands in Jeonnam Area)

  • 이종원;윤호근;강신호;안종빈
    • 한국습지학회지
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    • 제24권4호
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    • pp.224-255
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    • 2022
  • 본 연구는 전남권역 우량 산림습원 32개소를 대상으로 1차 조사와 2차 조사에서의 관속식물상 변화를 살펴보고, 이를 바탕으로 우량 산림습원의 향후 모니터링 체계구축과 효과적인 관리를 진행하고자 수행되었다. 조사는 2015년부터 2021년까지 조사지역을 4-5년 주기로 계절별로 2회 이상 조사를 실시하였다. 전남권역 우량 산림습원 32개소의 식물상 변화는 103과 311속 496종 16아종 38변종 6품종 556분류군에서 111과 362속 599종 16아종 51변종 8품종 674분류군으로 증가하였다. 한반도 특산식물은 12분류군에서 16분류군, 한반도 관속식물 적색목록은 18분류군에서 24분류군, 식물구계학적 특정식물은 95분류군에서 123분류군, 한반도 석호식물은 286분류군에서 328분류군, 침입외래식물은 17분류군에서 26분류군으로 전체 식물상이 증가함에 따라 특기할만한 식물도 동시에 증가하였다. 하지만 느리미고사리, 나도고사리삼, 개쓴풀, 개박하 등은 지역적으로 절멸하여 현지 내외 복원 전략이 수립되어야 한다. 습지선호도에 따른 유형이 구분된 식물은 절대습지식물은 69분류군에서 78분류군, 임의습지식물은 63분류군에서 69분류군, 양생식물은 64분류군에서 82분류군, 임의육상식물은 85분류군에서 96분류군, 절대육상식물은 275분류군에서 348분류군으로 확인되었다. 습지식물류의 분포 비율은 약간 감소하고 육상식물의 분포 비율은 다소 증가하여 산림습원 육화에 대한 대책을 마련하고 경계를 구분할 수 있는 조사기법 등을 개발되어야한다. 그리고 산림습원을 효과적으로 보전할 수 있는 산림유전자원보호구역으로 확대 지정하여 체계적으로 관리·감독해야 한다.

A THERMO-ELASTO-VISCOPLASTIC MODEL FOR COMPOSITE MATERIALS AND ITS FINITE ELEMENT ANALYSIS

  • Shin, Eui-Sup
    • Journal of Theoretical and Applied Mechanics
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    • 제3권1호
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    • pp.45-65
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    • 2002
  • A constitutive model on oorthotropic thermo-elasto-viscoplasticity for fiber-reinforced composite materials Is illustrated, and their thermomechanical responses are predicted with the fully-coupled finite element formulation. The unmixing-mixing scheme can be adopted with the multipartite matrix method as the constitutive model. Basic assumptions based upon the composite micromechanics are postulated, and the strain components of thermal expansion due to temperature change are included In the formulation. Also. more than two sets of mechanical variables, which represent the deformation states of multipartite matrix can be introduced arbitrarily. In particular, the unmixing-mixing scheme can be used with any well-known isotropic viscoplastic theory of the matrix material. The scheme unnecessitates the complex processes for developing an orthotropic viscoplastic theory. The governing equations based on fully-coupled thermomechanics are derived with constitutive arrangement by the unmixing-mixing concept. By considering some auxiliary conditions, the Initial-boundary value problem Is completely set up. As a tool of numerical analyses, the finite element method Is used with isoparametric Interpolation fer the displacement and the temperature fields. The equation of mutton and the energy conservation equation are spatially discretized, and then the time marching techniques such as the Newmark method and the Crank-Nicolson technique are applied. To solve the ultimate nonlinear simultaneous equations, a successive iteration algorithm is constructed with subincrementing technique. As a numerical study, a series of analyses are performed with the main focus on the thermomechanical coupling effect in composite materials. The progress of viscoplastic deformation, the stress-strain relation, and the temperature History are careful1y examined when composite laminates are subjected to repeated cyclic loading.

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교육시설 리모델링을 위한 에너지 절감 요소기술의 성능 평가 - 노후 중학교 건물 중심으로 - (Evaluating Performance of Energy Conservation Measures for Remodeling Educational Facilities - Focused on Deteriorated Middle School Buildings -)

  • 이상춘;최영준;최율
    • KIEAE Journal
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    • 제12권4호
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    • pp.105-110
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    • 2012
  • Recently, all of the world are facing with a serious environmental crisis of global warming due to excessive energy consumptions. The Korean Government, taking over 97% of dependence on foreign energy, has made various efforts on reducing energy and greenhouse gas emission under the motto of "Low-Carbon Green Growth". Since the building sector takes 24% of domestic energy consumption, many design standards and regulations on saving energy in new buildings have been established. However, applications of energy saving designs and techniques on the remodeling process at deteriorated buildings including educational ones have been lack. Under a situation where the number of deteriorated schools accounts for up to 50%, this paper evaluated the performances of factors for reducing energy at deteriorated middle school buildings through an energy simulation tool on a standard school model. As a result, among factors of insulation, window's SHGC, southern louver, indoor setup temperature, and system efficiency, all other factors except window's SHGC and southern louver proved contribute to reduce energy at deteriorated middle school buildings, compared with the baseline energy consumption.

현대 패션 전시의 유형별 연출 기법과 특성 연구 (A Study on Display Techniques and Characteristics of Contemporary Fashion Exhibitions)

  • 정다운;하지수
    • 한국의류학회지
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    • 제42권5호
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    • pp.823-838
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    • 2018
  • The article surveys the technique and characteristics of contemporary fashion exhibitions in terms of fashion museography and fashion curation. The article reviewed both a literature study on the history of fashion exhibition focused on the display technique as well as a case study of domestic and international contemporary fashion exhibitions. The results of the article is as follows. Fashion brand exhibitions are about building competitive business advantage by planning differentiated contents. It gives viewers a brand fantasy and increases brand loyalty. This type mainly displays the latest collections on the commercial purpose as well as uses diverse mediums and high technology to make a spectacular space that provides an immersive experience to the viewer. Second, the museum fashion exhibition focuses on the roles of fashion in terms of social, cultural and artistic aspects that also focus on public education. The presentation technique emphasizes careful collection conservation rather than celebrate fashion business. The article is to encourage a further scholar discourse of fashion curatorial practice and theory.

우유의 가열 및 비가열 살균 기술에 관한 연구 동향 (Impact of Thermal and Nonthermal Technologies in Milk Processing)

  • 박중근;이여진;윤준용;엄애선
    • Journal of Dairy Science and Biotechnology
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    • 제33권3호
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    • pp.223-229
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    • 2015
  • Milk is a food with high nutritional value as it contains abundant water, proteins, vitamins, lactose, fat, minerals, enzymes, etc. However, in order to make milk suitable for intake, it should be thermally treated to eliminate microbiologically hazardous factors. Heat treatment is an essential sanitation process for milk, but various precautions must be taken in order to process and preserve it. Therefore, various techniques should be developed to minimize the nutrient loss and to ensure that milk is safe for consumption, conservation, and distribution. However, the existing thermal pasteurization methods are harmful and increase the nutrient loss; moreover, no new thermal pasteurization methods are being researched that are safe for the human health and minimize the nutrient loss. Hence, this study aims to review new processes for thermal (low temperatures) and no thermal pasteurization methods that can minimize the nutrient loss during milk pasteurization.

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기존 오피스건물 에너지성능지표에 따른 설계기법 연구 (A Study on the Design Technique for Energy Performance Indicators of Existing Office Buildings)

  • 정형태;이유나;김인수;안종욱
    • 에너지공학
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    • 제27권3호
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    • pp.28-35
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    • 2018
  • 세계 각국에서는 환경오염이나 에너지절감을 위한 방안으로 건축물에 대한 가이드라인과 제도적 지원이 활성화되고 있다. 우리나라에서도 2013.09.01. 개정된 "건축물의 에너지절약 설계기준"에 따라 기준들이 마련되고 신축 건축물에 대한 제로에너지빌딩화가 권장사항에서 의무화과정으로 가고 있다. 그럼에도 불구하고 소형건물에 대한 정부의 구속력은 미비한 실정이다. 이에 최근에 시공한 오피스건물(외단열기법 적용)에 대해 에너지 절감효과를 분석하였고 추가적으로 에너지 절감을 위한 이중외피기법을 제안하였다.

주요사료작물의 곤포 Silage 조제이용에 관한 연구 III. 작물별 곤포 silage의 일반 성분과 에너지함량 평가 (Study on Baled Silage Making of Selected Forage Crop and Pesture Grasses III. Evaluation of chemical components and energy contents of baled silage with selected forage)

  • 김정갑;한민수;김건엽;한정대;진현주;신정남
    • 한국초지조사료학회지
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    • 제16권1호
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    • pp.87-92
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    • 1996
  • The quality of silages, made from whole crop barley, rye, spring oat, Italian ryeglass, orchardgrass, alfalfa and grass-legume pasture mixtures, were evaluated under two different conservation techniques in baled silage making (BS) and conventional silages(CS). Crops materials were harvested at the stage of the greatest dry matter accumulation(hard dough for barley, soft dough for rye and oat, late bloom for Italian ryegrass and others pasture species), and baled in a self constructed square baling chamber weighted by 25~30kg in dry matter basis. Each bales were wrapped with 0.05mm thick polyethylen plastic film and stored six months long in stack silos. Barley, rye, oat and Italian ryegrass including of pasture crops produced higher quality silages in the baled silage making, due to better organic acid fermentation and lower nutrient losses during the period of storage than those in the conventional silages. TDN contents of barley silages were 65.3% in BS and 63.7% in CS, NEL value of barley silages was improved hum 6.48MJ(CS) to 6.61MJ/kg(BS) in dry matter basis. Silage quality of rye, oat and pasture crops were also improved markedly in the baled silage utilization.

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On-Off 제어기를 이용한 가변추력 고체추진 기관의 압력제어 (Pressure Control of a Variable Thrust Solid Propulsion System Using On-Off Controllers)

  • 권순규;김영석;고상호;서석훈
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2011년도 제37회 추계학술대회논문집
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    • pp.942-948
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    • 2011
  • 고체추진기관은 구조가 비교적 간단하고 장기적 저장성이 우수한 반면에 일반적으로 추력의 조절등에 한계성을 가지고 있다. 본 논문에서는 구현의 용이함과 에너지 효율성이 좋은 on-off 제어기법을 이용한 가변추력 고체추진 기관의 압력 제어를 위한 제어기를 소개한다. 연소기 내 압력제어를위해 질량보존만을 고려한 추진기관의 연소기 내 압력변화 모델에 대하여 고전적인 비례-적분 제어기와 같은 연속적 제어 기법과 PWM, PWPFM과 같은 on-off 제어기를 설계하고 시뮬레이션을 통해 결과를 비교한다.

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대단면터널 특성을 고려한 지보설계 개선방안 연구 (Large-span Tunnel Support Design supplemented by Analytical Methods)

  • 정재호;이희석;허종석;윤상길
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2006년도 춘계 학술발표회 논문집
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    • pp.949-959
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    • 2006
  • Despite of the popularity of using empirical methods for support design, empirical rules suffer from the inherent problem of providing no indication of the safety degree of the design. For the support design of large span tunnel, it was considered that the empirical design guidelines should be augmented by more explicit design methods. This paper presents an overview of the analytical support design methodology that is used to refine initial empirical recommendations. The initial support design supplemented by analytical methods is validated by probabilistic and deterministic approach applied to stress-induced and structurally controlled gravity-driven instability problem each. As a result, the extent of the potential failure zone is sorted out and numerical parametric studies were performed to gain insight into the overall behavior of tunnel in the potential failure zone. Concequently, it was decided that additional conservation techniques have to be planed as a reserved support pattern.

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Dynamic Changes of Newly formed Wetlands in the Yellow River Mouth Based on GIS and Remote Sensing

  • Zhao, Gengxing;Shi, Yanxi;Chen, Weifeng;Li, Jing;Ann, Seoung-won;Kim, Young-chil;Jung, Jea-hoon;Chae, Soo-Cheon
    • 한국환경과학회지
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    • 제12권2호
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    • pp.133-137
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    • 2003
  • The Yellow River delta is an important region where coastal and newly formed wetlands distribute in north China. Based on satellite remote sensing images and GIS techniques, this paper tends to delineate the dynamic changes of newly formed wetland in the Yellow River mouth from 1986.5 to 1996.10. Our results show that the newly formed wetland increased by 24.9 $\textrm{km}^2$ per year. Before 1990. 1 and it decreased by 2.40 $\textrm{km}^2$ per year after that. The northern and southwestern parts of the Yellow River mouth are main positions of decrease and the southern and the estuary parts are main positions of increase. The advancing rate of river mouth extending into the Bo Sea is decreasing obviously. The reason for that is the decreasing of water and sediments in the Yellow River, which caused by the increasing use of water and soil conservation on upper reach.