• 제목/요약/키워드: Green method

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積層材料의 熱擴散係數測定을 위한 軸對稱 二次元 熱擴散方程式의 解析 (An Analysis of Axisymmetric Two Dimensional Heat Diffusion Equation to Measure the Thermal Diffusivity of Layered Materials)

  • 김진원;이흥주
    • 대한기계학회논문집
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    • 제10권3호
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    • pp.349-356
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    • 1986
  • 본 논문에서는 열손실에 의한 오차를 배제하기 위하여 원판형시편의 전후면에 서의 열손실과 반경방향의 열손실을 고려하고 2층으로 된 적층재료의 열확산방정식을 Green함수를 이용하여 해석하므로서 피복재료들의 열물성치를 정확하게 측정하기 위한 임의의 축대칭 열원의 펄스를 사용하여 열손실 및 펄스시간의 효과에 의한 오차를 최 소화 할 수 있는 방법을 제시 하고자 한다.

반복 그린 함수 방법을 이용한 도파관 스텁 구조의 새로운 해석법 (Novel Analysis of Waveguide Stub Structure Using Iterative Green's Function Method)

  • 조용희
    • 한국콘텐츠학회논문지
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    • 제7권2호
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    • pp.125-131
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    • 2007
  • 학부생들이 쉽게 사용할 수 있는 기법인 반복 그린 함수 방법(IGFM)을 이용하여 복잡한 전자파 도파관스텁 구조를 이론적으로 엄밀하게 해석한다. lGFM은 그린 함수 접근법과 영역 반복법을 이용한다. IGFM의 간단한 공식화를 위해 단순한 수학 방정식만을 사용한 물리적인 반복 메커니즘을 이용한다. 전형적인 전자파 도파관 구조인 평행판 E평면 T접합 스텁에 대한 산란 특성을 IGFM 관점에서 이론적으로 공식화한다. 수치해석 결과를 주파수에 대한 반사와 투과 전력 관점에서 보인다.

A COMPARISON OF METHOD FOR ESTIMATING FRACTIONAL GREEN VEGETATION COVER DERIVED FROM HYEPRION HYPERSPECTRAL DATA

  • Yoon, Yeo-Sang;Kim, Yong-Seung
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2006년도 Proceedings of ISRS 2006 PORSEC Volume II
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    • pp.848-851
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    • 2006
  • Green vegetation is one of the most critical factors for environment conditions thorough modulating evapotranspiration and absorption of solar radiation. Thus, fractional green vegetation cover (FVC) plays an important role in observing and managing environment. Remote sensing provides a seemingly obvious data source for quantifying FVC over large area. Therefore we compared a set of methods for estimating FVC using hyperspectral remote sensing data. For our study, we used Hyperion imagery acquired in April, 2002. In order to achieve our efforts, we analyzed simple NDVI-based method and spectral mixture analysis (SMA) models that were applied a variety of combinations of possible endmembers.

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Thermal conductivity of PLA-bamboo fiber composites

  • Takagi, Hitoshi;Kako, Shuhei;Kusano, Koji;Ousaka, Akiharu
    • Advanced Composite Materials
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    • 제16권4호
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    • pp.377-384
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    • 2007
  • 'Green' composites were fabricated from poly lactic acid (PLA) and bamboo fibers by using a conventional hot pressing method. The insulating properties of the PLA-bamboo fiber 'green' composites were evaluated by determination of the thermal conductivity, which was measured using a hot-wire method. The thermal conductivity values were compared with theoretical estimations. It was demonstrated that thermal conductivity of PLA-bamboo fiber 'green' composites is smaller than that of conventional composites, such as glass fiber reinforced plastics (GFRPs) and carbon fiber reinforced plastics (CFRPs). The thermal conductivity of PLA-bamboo fiber 'green' composites was significantly influenced by their density, and was in fair agreement with theoretical predictions based on Russell's model. The PLA-bamboo fiber composites have low thermal conductivity comparable with that of woods.

The extraction method for the best vegetation distribution zone using satellite images in urban area

  • Jo, Myung-Hee;Kim, Sung-Jae;Lee, Kwang-Jae
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.908-910
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    • 2003
  • In this paper the extraction method for the best suitable green vegetation area in urban area, Daegu, Korea, was developed using satellite images (1994, 1999, Landsat TM). For this, the GIS overlay analysis of GVI (Green Vegetation Index), SBI (Soil Brightness index), NWI (None-Such wetness Index) was performed to estimate the best suitable green vegetation area. Also, the statistical documents, algorithm and Tasseled-Cap index were used to recognize the change of land cover such as cultivation area, urban area, and damaged area. Through the result of this study, it is possible to monitor the large sized reclamation of land by drainage or damaged area by forest fires. Moreover, information with the change of green vegetation and the status of cultivation by GVI, but also moisture content by percentage by NWI and surface class by SBI can be obtained.

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Frequency-Modulated Pulse-Amplification Method for Reducing Pulse Shape Distortion

  • Jeong, Jihoon;Cho, Seryeyohan;Hwang, Seungjin;Yu, Tae Jun
    • Journal of the Korean Physical Society
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    • 제73권11호
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    • pp.1637-1643
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    • 2018
  • To reduce the laser pulse shape distortion accompanying the amplification process and achieve an intended output pulse shape in the Nd:YAG amplifier chain, we propose a frequency-modulated pulse-amplification method. Assuming carrier-frequency-modulated seed pulses, we numerically simulate the pulse amplification in an Nd:YAG amplifier chain where severe distortion occurs. For the calculation, we develop a modified Frantz-Nodvik equation, which enables two inputs with different carrier frequencies. The simulation results indicate that the temporal contrast of the seed pulse needed to obtain a flat output pulse shape is reduced by 16 - 25 dB when frequency modulation is applied.

Supplier Evaluation in Green Supply Chain: An Adaptive Weight D-S Theory Model Based on Fuzzy-Rough-Sets-AHP Method

  • Li, Lianhui;Xu, Guanying;Wang, Hongguang
    • Journal of Information Processing Systems
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    • 제15권3호
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    • pp.655-669
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    • 2019
  • Supplier evaluation is of great significance in green supply chain management. Influenced by factors such as economic globalization, sustainable development, a holistic index framework is difficult to establish in green supply chain. Furthermore, the initial index values of candidate suppliers are often characterized by uncertainty and incompleteness and the index weight is variable. To solve these problems, an index framework is established after comprehensive consideration of the major factors. Then an adaptive weight D-S theory model is put forward, and a fuzzy-rough-sets-AHP method is proposed to solve the adaptive weight in the index framework. The case study and the comparison with TOPSIS show that the adaptive weight D-S theory model in this paper is feasible and effective.

옥상녹화 적용확대를 위한 녹색건축인증제도 개선방안 연구 - 미국 LEED 및 영국 BREEAM의 비교·분석을 중심으로 - (Study on Improvement Measures of Green Standard for Energy and Environmental Design for Expansion of Applying Green Roof - Focused on LEED in the USA and BREEAM in the UK -)

  • 김지현;권혁삼;김정곤;이범식
    • 대한건축학회논문집:구조계
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    • 제34권2호
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    • pp.75-82
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    • 2018
  • Green roof in Korea has been recognized as part of landscape area and local governments enacted municipal ordinance for supporting green roof thereby assisting part of expenses spent for green roof within a range of budget for buildings which are eligible for the green roof support of existing buildings. However, it is necessary to enforce a regulation of mandatory green roof for new buildings in order to expand green roof application and provide a variety of assistances such as subsidy payment, tax relief, and mitigation of floor area ratio-related regulation as done in other advanced nations. In particular, LEED(Leadership in Environmental and Energy Design) in the USA applies additional point directly for green roof in terms of the reduction in heat island effects. For example, the following items are beneficial to have additional points: habitat preservation or restoration, external space, rainwater management, reduction in outdoor water usage, minimum energy performance, and optimum energy performance. In addition, the BREEAM(Building Research Establishment Environmental Assessment Method) in the UK specifies green roof as one of assessment items to be complied in terms of diversity of species. As such, LEED and BREEAM reflect direct and indirect effects of green roof on assessment criteria, which suggest a direction to green building certification criteria in Korea where only additional points are given for green roof according to soil depth.

서울시 아파트단지내 조경수목 배식특성 및 개선 연구 (Improvement Planting Method and Characteristics of Planting Design with Ornamental Trees in Apartment Complex, Seoul)

  • 이경재;한봉호;이수동
    • 한국환경생태학회지
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    • 제18권2호
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    • pp.236-248
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    • 2004
  • 본 연구는 서울시에 조성된 아파트단지내 녹지를 대상으로 식재개념, 식재밀도, 식재유형 및 패턴 등 배식특성을 조사.분석하여 개선방안을 제시하고자 실시하였다. 대상지는 아파트단지 녹지면적이 크게 달라지는 시기의 대표대상지인 1978년에 준공된 강서구 화곡주공아파트(2단지)(용적률:99%), 1983년에 준공되 강남구 삼익그린아파트(2차)(용적률:175%), 1992년에 준공된 강서구 동신대아아파트(용적률:225%)를 선정하였으며 녹지를 전면녹지, 측면녹지, 후면녹지로 구분하였다. 대상지의 녹지유형별 식재개념은 경관식재로만 이루어져 시기에 따른 차이는 없었으며 식재종에 있어서도 외래종 조경수목이 주를 이루어 녹지공간별 차이는 없었다. 아파트단지의 식재밀도은 교목 및 아교목층 0.0~0.2주/$m^{2}$로 관목층의 식재밀도가 부족하였으나 조성시기에 따른 식재밀도의 차이는 없었다. 층위구조는 교목.아교목층과 관목층 수목이 각각 다른 위치에 평면적으로 식재된 단층구조이었으며 녹지공간과 관계없이 독립식재, 열식재, 부등변삼각식재가 주로 활용되었다. 아파트 단지내 녹지는 공가별 식재개념에 따라 식재종, 식재밀도, 층위구조, 식재패턴이 다양하게 이루어져야 하므로 식재개념에 차별화시키기 위하여 전면녹지는 시각적 차폐와 미적인 기능, 후면녹지는 녹지량 증지 및 생태적 개념, 측면녹지는 녹지량을 증진을 주된 목적으로 조성할 것을 제안하였다.

940K bbls FPSO의 선수갑판 Green Water에 관한 연구 (A Study of Green Water on the Bow Deck of 940K bbls FPSO)

  • 김용직;신기석;추교덕;서용석;이춘기;김문성
    • 한국해양공학회:학술대회논문집
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    • 한국해양공학회 2004년도 학술대회지
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    • pp.309-313
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    • 2004
  • Prediction of green water loads acting an the bow deck is an essential part for the design of bow structures against the green water impact. Proper technique of the green water simulation is highly required for the prediction of green water loads. In this paper, a new numerical method for green water simulation, which is based an predictor-corrector-upwind finite difference scheme of the 2nd kind, is introduced. Through the comparisons between computed' results and experimental measurements, it is verified that the present numerical tool is adequate as a practical calculation tool for the green water problem.

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