• 제목/요약/키워드: green technology

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구난장치 구동용 유압 피스톤 펌프 개발에 관한 연구 (A Study for Development of Hydraulic Piston Pump for Driving Rescue Equipment)

  • 이지환;이경준;김경수;강명철;이현철
    • 한국군사과학기술학회지
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    • 제21권3호
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    • pp.255-263
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    • 2018
  • This paper investigated design requirements for piston pumps, which were used as the power source of light rescue vehicle, and designed a piston pump satisfying such requirements. In order to satisfy the driving specification of the rescue device, the pump needs to be designed using the displacement volume of 110 cc/rev, the pressure of 350 bar and the rotation speed of 2,200 rev/min. The design was verified by flow and structural analyses respectively. The shape of the piston pump was optimized in terms of both flow characteristics and structural stability. A test equipment was also fabricated to verify the developed piston pump and test conditions were established. Finally, the developed piston pump was tested for its performance and operating temperature.

FIA에 의한 유기산의 해리상수 측정에 관한 연구 (A Study on the Measurement of Dissociation Constant of Organic Acid with FIA)

  • 이재성;박현미;김희진;이강봉
    • 분석과학
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    • 제7권2호
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    • pp.173-179
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    • 1994
  • 빠른 시간내에 적은 시료로(mg 단위) FIA와 Diode Array Spectrophotometry를 이용하여 해리상수를 구할 수 있는 방법을 개발하는 데 실험의 비중을 두었고, 그 대상으로 Bromo Cresol Green을 사용하였다. 소량의 산 염기를 가할 때 제일 sensitive한 발색반응을 보이는 지시약의 pK는 7.0임이 컴퓨터에 의해 계산되었다. Spectrophotometry를 이용한 Bromothylmol Blue와 Bromocresol Green은 Kielland 방법에 의한 Activity를 보정해 준 후 pKa가 각각 7.31과 4.82를 얻었다(Reported value by Bishop 7.30, 4.79). FIA에 의한 Bromocresol Green의 pKa값은 4.78을 얻어 다른 방법과 유사함을 알 수 있었다.

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수술현미경용 다중형광 관측 시스템 연구 (Development of Indocyanine Green and 5-Aminolevulinic Acid Detection System for Surgical Microscope)

  • 김홍래;이현민;윤웅배;김영재;김석기;유헌;주재영;김광기;이승훈
    • 대한의용생체공학회:의공학회지
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    • 제36권1호
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    • pp.16-21
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    • 2015
  • Indocyanine green(ICG) and 5-aminolevulinic acid(5-ALA) have been widely used to mark blood vessels or tumors. However, fluorescent dye detection systems were designed to use one type of dyes only. In this study, we proposed a detection system capable of detecting Indocyanine green and 5-aminolevulinic acid. Multiple filters and light sources are integrated into a single system. In this study, we performed analysis of fluorescent dyes and configured a detection system. During the analysis, it was found that Indocyanine green and 5-aminolevulinic acid have the maximum intensity at $40{\mu}M$. We designed light source for fluorescent dyes and conducted compatibility test using a commercial surgical microscope. The fluorescent dye detection system was configured based on the experimental results. The developed system successfully detects Indocyanine green and 5-aminolevulinic acid. Therefore, more efficient surgical operations can be achieved using both fluorescent dyes at the same time. We expect that the developed system can increase the survival rate of patients.

CRITICAL HEAT FLUX ENHANCEMENT IN FLOW BOILING OF Al2O3 AND SiC NANOFLUIDS UNDER LOW PRESSURE AND LOW FLOW CONDITIONS

  • Lee, Seung-Won;Park, Seong-Dae;Kang, Sa-Rah;Kim, Seong-Man;Seo, Han;Lee, Dong-Won;Bang, In-Cheol
    • Nuclear Engineering and Technology
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    • 제44권4호
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    • pp.429-436
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    • 2012
  • Critical heat flux (CHF) is the thermal limit of a phenomenon in which a phase change occurs during heating (such as bubbles forming on a metal surface used to heat water), which suddenly decreases the heat transfer efficiency, thus causing localized overheating of the heating surface. The enhancement of CHF can increase the safety margins and allow operation at higher heat fluxes; thus, it can increase the economy. A very interesting characteristic of nanofluids is their ability to significantly enhance the CHF. Nanofluids are nanotechnology-based colloidal dispersions engineered through the stable suspension of nanoparticles. All experiments were performed in round tubes with an inner diameter of 0.01041 m and a length of 0.5 m under low pressure and low flow (LPLF) conditions at a fixed inlet temperature using water, 0.01 vol.% $Al_2O_3$/water nanofluid, and SiC/water nanofluid. It was found that the CHF of the nanofluids was enhanced and the CHF of the SiC/water nanofluid was more enhanced than that of the $Al_2O_3$/water nanofluid.

중소기업의 외부 기술 연구개발 정보 네트워크의 다양성과 녹색 경영 성과 (Small and Medium Enterprises' External Technology R&D Information Network Diversity and Green Management Performance)

  • 허용석
    • 디지털융복합연구
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    • 제15권12호
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    • pp.187-194
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    • 2017
  • 환경오염과 지구 온난화가 더욱 더 심각해지면서 녹색 경영이 중소기업에 더욱 더 중요해지고 있다. 본 연구는 중소기업의 녹색 경영 성과에 양(+)의 영향을 미치는 요인들을 분석하기 위해 한국의 2,200개의 중소기업 데이터를 대상으로 실시한 최소자승 회귀분석 결과를 통해 다음과 같은 두 가지 주요 시사점들을 제공한다. 첫째, 중소기업의 외부 기술 연구개발 정보 네트워크의 다양성은 기술 연구개발로 인한 녹색 경영 성과에 정(+)의 영향을 미친다. 둘째, 중소기업의 기술개발로 인한 생산 공정의 개선은 외부 기술 연구개발 정보 네트워크의 다양성이 기술개발로 인한 녹색 경영 성과에 미치는 양(+)의 영향을 부분적으로 매개 한다.

옥상녹화에서 혼합식재에 따른 블루페스큐와 지피초화류의 생육 반응 (Effect of Companion Planting on Growth of Festuca glauca 'Elijah Blue' and Flowering Ground-cover Plants on Green Roofs)

  • 윤용한;서수현;이선영;오득균;주진희
    • 한국환경복원기술학회지
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    • 제24권5호
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    • pp.15-23
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    • 2021
  • This study was carried out to suggest an appropriate plant combination by evaluating the growth of flowering ground-cover plants planted with Festuca glauca 'Eljiah Blue' on the roof-top environment. As for the plant materials, Allium senescens and Chrysanthemum coreanum which are shorter than Festuca glauca 'Eljiah Blue' and Sedum takesimense and Agastache rugosa which are taller than Festuca glauca 'Eljiah Blue' were selected. Festuca glauca 'Eljiah Blue' was planted on Conrol, and Festuca glauca 'Eljiah Blue' with Allium senescens (T1), Festuca glauca 'Eljiah Blue' with Sedum takesimense (T2), Festuca glauca 'Eljiah Blue' with Agastache rugosa(T3), and Festuca glauca 'Eljiah Blue' with Chrysanthemum coreanum (T4) were planted in each experimental plot. Plant height and covering rate were measured to evaluate the growth of Festuca glauca 'Eljiah Blue'. Also, relative growth rate (RGR) of plant height, RGR of plant width, and mortality rate of the flowering ground-cover plants were estimated. Plant height and cover rate of Festuca glauca 'Eljiah Blue' was greatest in T3. RGR of plant height was greater in the order of Agastache rugosa, Allium senescens, Chrysanthemum coreanum, and Sedum takesimense. In particular, RGR of plant width was also greatest for Agastache rugosa. Mortality rates of Agastache rugosa and Allium senescens were lowest at 11%. Therefore, based on good growth of Festuca glauca 'Eljiah Blue' planted with Agastache rugosa, these results were suggested as a desirable combination of plant species for rooftop gardening.

Styrene Epoxidation over Cobalt Cyclam Immobilized SBA-15 Catalyst

  • Sujandi;Prasetyanto, Eko Adi;Han, Sang-Cheol;Park, Sang-Eon
    • Bulletin of the Korean Chemical Society
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    • 제27권9호
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    • pp.1381-1385
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    • 2006
  • Cobalt (cyclam) complex has been successfully immobilized onto SBA-15, and proven to be an active catalyst for the epoxidation of styrene with tert-butyl hydroperoxide as a terminal oxidant. The selectivity for styrene oxide was observed to be up to 66% with 40% styrene conversion after 12h reaction time. The reversible redox cycle between Co(III) and Co(II) couple which was supposed to play key role during the epoxidation reaction was supported by a cyclic voltametry analysis. The textural properties of the catalyst was characterized by XRD, N2 adsorption-desorption, and TEM analysis.

Q-TRIZ를 활용한 지능형 쏠라 그린조명시스템 개발 (The Development of Intellectual Solar Green Street Lighting using Q-TRIZ)

  • 허용정;홍성도;임사환
    • 반도체디스플레이기술학회지
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    • 제10권3호
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    • pp.43-47
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    • 2011
  • Recently the government banners green growth promises as a paradigm of national development which are to reduce greenhouse gases and environmental pollution by exhaust gases from automobiles. Existing in all countries around the world by using fossil fuels to minimize environmental changes are developing a new alternative energy sources. Among the emerging alternative energy, using solar energy technology is applied across the industry, but the maintenance and repair to integrate solar cells and has been a problem occurs. To prolong the life of cells integrated on a solar cell is exposed when the non-eye, etc., when not integrated by the solar cells should not be exposed. In order to resolve these contradictions, a intellectual solar green street lighting was developed by using Q(Quick)-TRIZ.

Microwave Synthesis of Hydrotalcite by Urea Hydrolysis

  • Yang, Zhiqiang;Choi, Kwang-Min;Jiang, Nanzhe;Park, Sang-Eon
    • Bulletin of the Korean Chemical Society
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    • 제28권11호
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    • pp.2029-2033
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    • 2007
  • Hydrotalcite, layered double hydroxides (LDH), with hexagonal morphology has been rapidly synthesized by microwave reaction within 1 hour by urea hydrolysis from homogeneous solution. Different synthesis parameters, Mg/Al molar ratio, microwave reaction temperature and microwave power were systematically investigated. Pure hydrotalcite phase was obtained for Mg/Al ratios of 2:1 and 3:1, and higher reaction temperature gave higher crystallinity. The hydrotalcite synthesized at 600W power shows the highest crystallinity and more homogeneous crystal size distribution. The hydrotalcite samples were characterized by powder X-ray diffraction (XRD), simultaneous thermogravimetric/differential thermal analysis (TG/DTA), Fourier Transform Infrared (FT-IR) and Scanning electron micrograph (SEM).

Gas transport properties of alumina composite membranes

  • Lee, Hong-Joo;Hiroyuki Yamauchi;Hiroyuki Suda;Kenji Haraya
    • 한국막학회:학술대회논문집
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    • 한국막학회 2004년도 Proceedings of the second conference of aseanian membrane society
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    • pp.128-131
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    • 2004
  • The composite mesoporous ceramic membranes were prepared with ${\gamma}$-alumina and poly (2, 6-dimethyl-l, 4-pyphenylene oxide) (PPO) on the surface of the macroporous $\alpha$-alumina ceramic membranes and the permeation results were compared with those of the $\alpha$-alumina membrane for large-scale applications. In the results of the transport experiments, the ceramic membranes gave high gas permeances mainly due to Knudsen diffusion and surface diffusion as an additional mechanism. And, the polymer modification increased the permeances of the strongly adsorbing gas components. In this study the modifications of alumina ceramic membranes could increase the gas permeation performances especially for the strongly absorbing gas components.

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