• 제목/요약/키워드: green technology

검색결과 4,930건 처리시간 0.035초

Development of tiny green laser for mobile projectors

  • Yu, N.E.;Jung, C.;Yu, B.;Lee, Y.L.;Kim, I.S.;Choi, J.W.;Ko, D.K.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.476-477
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    • 2009
  • The smallest green laser containing a built-in temperature controlling unit has been demonstrated. The device volume was just 0.5 cubic centimeters, which is nearly the same size as existing red and blue diode lasers, has an electrical-to-optical conversion efficiency of 10% and 150 mW power output. Furthermore as an alternative approach for compact green laser development, a quasi-phase matching method with wide spectral bandwidth for the reduction of speckle noise will be presented.

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건물 부착형 고경량 유연성 슁글드 태양광 모듈 (Fabrication of Lightweight Flexible c-Si Shingled Photovoltaic Modules for Building-Applied Photovoltaics)

  • 김민섭;박민준;신진호;이은비;정채환
    • Current Photovoltaic Research
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    • 제10권4호
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    • pp.107-110
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    • 2022
  • Lightweight and flexible photovoltaic (PV) modules are attractive for building-integrated photovoltaic (BIPV) applications because of their easy construction and applicability. In this study, we fabricated lightweight and flexible c-Si PV modules using ethylene tetrafluoroethylene (ETFE) front cover and shingled design string cells. The ETFE front cover instead of glass made the PV modules lighter in weight, and the shingled design string cells increased the flexibility. Finally, we fabricated a PV module with a conversion power of 240.08 W at an area of 1.25 m2 and weighed only 2 kg/m2. Moreover, to check the PV module's flexibility, we conducted a bending test. The difference of conversion power between the modules before and after bending shown was only 1.7 W, which showed a power reduction rate of about 0.7%.

가로세로 폭의 제어가 가능한 슁글드 디자인 태양광 모듈 제조 (Fabrication of Shingled Design Solar Module with Controllable Horizontal and Vertical Width)

  • 박민준;김민섭;이은비;김유진;정채환
    • Current Photovoltaic Research
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    • 제11권3호
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    • pp.75-78
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    • 2023
  • Recently, the installation of photovoltaic modules in urban areas has been increasing. In particular, the demand for solar modules installed in a limited space is increasing. However, since the crystalline silicon solar module's size is proportional to the solar cell's size, it is difficult to manufacture a module that can be installed in a limited area. In this study, we fabricated a solar module with a shingled design that can control horizontal and vertical width using a bi-directional laser scribing method. We fabricated a string cell with a width of 1/5 compared to the existing shingled design string cells using a bi-directional laser scribing method, and we fabricated a solar module by connecting three strings in parallel. Finally, we achieved a conversion power of 5.521 W at a 103 mm × 320 mm area.

절곡 강판 일체형 고출력 슁글드 태양광 모듈 제조 (Fabrication of High-power Shingled PV Modules Integrated with Bent Steel Plates for the Roof)

  • 이은비;박민준;김민섭;신진호;윤성민
    • Current Photovoltaic Research
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    • 제11권2호
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    • pp.54-57
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    • 2023
  • Recently, requirements for improving the convenience of constructing BIPV (Building Integrated Photo Voltaic) modules had increased. To solve this problem, we fabricated shingled PV modules integrated with bent steel plates for building integrated photovoltaics. These PV modules could be constructed directly on the roof without the installation structure. We found optimal lamination conditions with supporting structures to fabricate a module on a bent steel plate. Moreover, we applied a shingled design to PV modules integrated with bent steel plates to achieve a high electrical output power. The shingled module with bent steel plates shows 142.80 W of solar-to-power conversion in 0.785 m2 area.

도시 녹지기반 특성에 따른 강우 유출수 비교 분석 - 성남시 분당신도시를 사례로 - (A Comparative Analysis of Stormwater Runoff with Regard to Urban Green Infrastructure - A Case Study for Bundang Newtown, SungNam -)

  • 박은진;강규이;이현정
    • 한국환경복원기술학회지
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    • 제11권6호
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    • pp.1-10
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    • 2008
  • The study was aimed at analyzing the relationship between the characteristics of urban green infrastructure and stormwater runoff in a small urban watershed composed of 22 drainage basins. The green areas of which soils are not sealed and allow water infiltrate, were examined for different types of green spaces. In a comparative study for drainage basins of which green spaces are 15.5% and 34.4%, respectively, runoffs were not different with the size of green space. It was attributed to that the increase of runoff by greater road area offset the advantage of greater green area. Another comparative measurement of runoff for drainage basins with similar green area size showed that runoff decreased with greater permeable area (school ground area) and smaller road area. The runoff measurements could address that runoff rates are affected not only by green area size but also by the type of green area and other land covers related to permeability and flow into drainage. It implicated that the improvement of urban green infrastructure as a functional unit for water infiltration and interception is important for stormwater runoff management.

Factors Affecting Consumer Purchasing Behavior: A Green Marketing Perspective in Vietnam

  • LE, Quang Hung
    • The Journal of Asian Finance, Economics and Business
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    • 제8권5호
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    • pp.433-444
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    • 2021
  • The study seeks to identify the factors affecting the green marketing element of students' food purchasing decision at Co-opMart supermarket chain in Ho Chi Minh City through the application of a mix of qualitative and quantitative research methods that include probability sampling and convenient sampling of 400 students from Ho Chi Minh City University of Technology (HUTECH). The data are analyzed with SPSS software using Cronbach's Alpha, Exploratory Factor Analysis, Multiple Linear Regression and PATH model to test the model through the intermediate variable 'student's perception' and the hypotheses, identifying the green marketing effects on HUTECH students' food purchasing decisions at Ho Chi Minh City Co-opMart supermarket chain. The results of the study identify four factors of the green marketing mix (4Cs), namely, green commodity, green cost, green convenience, and green communication. All these factors have an influence on the student's food purchasing decision at Co-opMart supermarket. Cost is the strongest factor eliciting student's interest in purchasing green products, followed by convenience, then communication. Commodity has the least impact on green purchasing decision. This study proposes some feasible solutions for Co-opMart managers to attract more students using green food in the complex situation of contaminated food, which is extremely harmful to consumers' health.

The Effect of Green Transformation on the Operating Efficiency of Green M&A Enterprises: Evidence from China

  • ZHOU, Lingling;LI, Wenqi;TEO, Brian Sheng-Xian;YUSOFF, Siti Khalidah Md
    • The Journal of Asian Finance, Economics and Business
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    • 제9권1호
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    • pp.299-310
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    • 2022
  • Environmental protection has been infused into the development of numerous fields by the Chinese government. The government's implementation of green development has also shifted its focus to green transformation and governance of highpolluting companies. In the context of green and sustainable development, this study employs DEA data envelopment analysis to compare the operating efficiency of listed firms that implemented Green Mergers and Acquisitions (M&A) in China in 2018. The conclusions of this study are as follows: First, China's green M&A enterprises are unevenly dispersed among the country's east, middle, and western regions. Second, compared to before the implementation of Green M&A, operational efficiency has improved in most industries. Third, the difference in Green M&A across industries is generally favorable, showing that most organizations have improved their operational performance as a result of Green M&A implementation. In 2018, however, the gap in operating efficiency is more negative. Fourth, whereas the eastern and western areas' operational efficiency has improved as a result of Green M&A, the central region's has not. Based on this conclusion, this study makes recommendations for China's future sustainable development of heavily polluted firms.

온도 의존적 재료물성치를 고려한 개선된 그린함수 기반 열응력 계산 (Thermal Stress Calculations Using Enhanced Green's Function Considering Temperature-dependent Material Properties)

  • 한태송;허남수;전현익;하승우;조선영
    • 한국생산제조학회지
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    • 제24권5호
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    • pp.535-540
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    • 2015
  • We propose an enhanced Green's function approach to predict thermal stresses by considering temperature-dependent material properties. We introduce three correction factors for the maximum stress, the time taken to reach maximum stress, and the time required to attain steady state based on the Green's function results for each temperature. The proposed approach considers temperature-dependent material properties using correction factors, which are defined as polynomial expressions with respect to temperatures based on Green's functions, that we obtain from finite-element (FE) analyses at each temperature. We verify the proposed approach by performing detailed FE analyses on thermal transients. The Green's functions predicted by the proposed approach are in good agreement with those obtained from FE analyses for all temperatures. Moreover, the thermal stresses predicted using the proposed approach are also in good agreement with the FE results, and the proposed approach provides better predictions than the conventional Green's function approach using constant, time-independent material properties.

Roles of Threat and Coping Appraisal in Adoption of Green Information Technology: Ordered Protection Motivation Theory Perspective

  • Lee, Namyeon;Jin, Yanshou;Kwon, Ohbyung
    • Asia pacific journal of information systems
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    • 제23권2호
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    • pp.87-109
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    • 2013
  • While many surveys show very positive attitudes on the part of consumers towards eco-friendly products, the market share actually reflecting green IT purchases remains low in most countries. The motivations behind green IT purchase behavior are still obscure. Several studies have addressed the question of green IT diffusion from economic and normative viewpoints in an attempt to interpret IT adoption behavior. This study comes at the question from a different angle, namely negative frame, examining threat and coping behaviors using the Ordered Protection Motivation (OPM) model and threat appraisal theory. The results show that attitudes toward fairness and positive change, which are precedents of threat appraisal, play an important role in determining threat appraisal. Perceived threats in the green IT arena include habit change and ecological change. Appraisal for coping with these threats directly affects initial adoption behaviors regarding available green IT, and then indirectly encourages the purchase of new green IT products.

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