• 제목/요약/키워드: Bang-Jae

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증착 온도 변화에 따라 성장시킨 Ga-doped ZnO 박막의 특성평가

  • 이민정;김성연;임진형;방정식;명재민
    • 한국표면공학회:학술대회논문집
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    • 한국표면공학회 2009년도 춘계학술대회 논문집
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    • pp.173-174
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    • 2009
  • 증착 온도를 변화시켜 성장시킨 Ga-doped ZnO 박막을 수소 열처리를 통해 구조적 전기적 광학적 성질을 기존의 투명 전극으로 사용되는 ITO (indium tin oxide) 물질을 대체할 수 있는 가능성을 확인하였다. 열처리 전 Ga-doped ZnO 박막의 증착온도가 증가함에 따라 전기적 성질이 향상되었지만 423 K 이상의 온도에서는 과잉 dopant인 Ga 으로 인한 기여도가 커져 $ZnGa_{2}O_{4}$$Ga_{2}O_{3}$ 상으로 인해 박막의 질이 저하되는 것을 확인할 수 있었다. 수소 열처리 후 과잉 dopant Ga 으로 인하여 상온에서 올린 박막만 전기적 성질이 향상되었지만 나머지 증착 온도 변화를 둔 박막에서는 큰 변화가 없었다.

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농촌마을에서 자연발효형 화장실의 통기성 매질 이용에 관한 연구 (Utilization of the Bulking Agents for Environment-friendly Toilet in Rural Village)

  • 강방훈;조순재
    • 한국지역사회생활과학회지
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    • 제17권2호
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    • pp.105-112
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    • 2006
  • The biodegradability test of bulking agents in feces composting process is conducted to increase the management efficiency for environment-friendly rural toilet developed by National Rural Resource Institute in 2001. In the case study through references and field study, ash, fallen leaves, and wood chips are commonly used in the ecological toilet. Extension officers and farmers prefer rice straw, fallen leaves, and chaff among the rural resources as a bulking agents in the aspect of getting and storage as the result of questionnaire survey. As the result of biodegradability test including the temperature change, $CO_2$ gas production, and C/N ratio change of composting pile under the condition of aerobic composting apparatus, rice straw and chaff are good bulking agents for environment-friendly rural toilet. It is recommended that easy getting materials among the above mentioned materials are used for bulking agents as the region and season in environment-friendly rural toilet.

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DIGITAL WATERMARKING OF SATELLITE IMAGERY USING THE ALGORITHM BASED ON A LOOK-UP TABLE METHOD

  • Bang, Yoon-Sik;Lee, Jae-Bin;Yu, Ki-Yun;Kim, Yong-Il
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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    • pp.18-21
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    • 2007
  • Digital image watermarking is a technology used in copyrighting of digital images by embedding unremovable informations. In this paper, a pixel-domain look-up-table-based watermarking algorithm is presented. With this methodology, the watermark was embedded in the host image, but we did not observe any distortion at certain specific region of interest. This means the proposed method is preferred in case of satellite images. Then, the image manipulation tool which is called 'StirMark' will be used to perform many kinds of attacks such as rotation, scaling, filtering and compression on the watermarked image. Finally, the effectiveness of a watermarking technique in terms of 'robustness' and 'data integrity' criteria will be measured by calculating PSNR of watermark and watermarked image.

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파일럿 규모의 폐기물 다단열분해 가스화시스템의 운전특성 (Operating Characteristics of Pilot Scale Multi-Staged Waste Pyrolysis & Gasification System)

  • 이정우;류태우;방병열;문지홍;이재욱;박상신;김낙주
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2009년도 추계학술대회 논문집
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    • pp.331-335
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    • 2009
  • A novel multi-staged waste pyrolysis & gasification system of pilot scale (~1 ton/day) is designed and constructed in Korea Institute of Industrial Technology. The pyrolysis & gasification system is composed of pyrolysis & gasification system, syngas reformer, syngas cleaning system, gas engine power generation system and co-combustion system. For each unit process, experimental approaches have been conducted to find optimal design and operating conditions. As a result, We can produce syngas with a calorific value of ~4000 kcal/$Nm^3$ and cold gas efficiency of the system is more than 55 % in case of waste plastic and oxygen as a gasifying agent.

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소방공무원의 작업강도 요인 분석에 관한 고찰 (Review - A factor analysis on firefighter's workload)

  • 방창훈;허만동;박은주;권정숙;이준경;이현정;신재숙
    • 한국화재소방학회:학술대회논문집
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    • 한국화재소방학회 2012년도 춘계학술발표회 초록집
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    • pp.309-312
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    • 2012
  • 본 연구에서는 소방공무원 작업강도의 요인을 분석하여 소방공무원의 안전을 위한 기초자료 제공을 목적으로 한다. 소방공무원의 작업강도에 미치는 내 외적요인들에 대하여 분석하였으며, 내적요인으로는 직무와 관련된 정신적 스트레스, 탈수, 체온, 체력과 영양, 외적요인으로는 환경조건, 개인보호복, 작업율과 기간, 경험과 기술 등으로 구분하였다. 소방공무원의 작업강도는 다양한 직무유형과 환경에 따라 복합적인 상호작용을 나타내며, 각 요인들 간의 인과관계 규명이 어렵고, 요인들에 노출이 장기화 된 후에 요인들이 미치는 영향이 발생하기도 한다.

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필타설치흙댐의 침수에 관한 연구 (A Study of the Seepage through Filter Installed Earth Dams)

  • 강관원;신방웅;이재기
    • 한국농공학회지
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    • 제19권2호
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    • pp.4417-4422
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    • 1977
  • This thesis is a result of theoretical and electrical experimental studies for the shape of Seepage on various Earth Dams. The decrement method of seepage through of water amount to earth Dam's was tested by means of experiment by the model constructed in the water tank. A study of the seepage through earth Dam's is necessary for a satisfactory of the same. An attempt was made in these investigations to study the problem of the seepage through homogeneous earth dams with filters located near the axis of the dam and filters extending in to upstream portion of the dam by the electrical analogy method. The experimental results were at variance with the graphical solution given by A Casagrande method. Some of the results were checked by relaxation method and by the circle criterion for drawing flow nets.

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A Rare Tropical Stonefly Brahmana flavomarginata (Plecoptera: Perlidae: Acroneuriinae) from Vietnam

  • Cao, Thi Kim Thu;Bae, Yeon Jae
    • Animal Systematics, Evolution and Diversity
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    • 제29권2호
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    • pp.179-183
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    • 2013
  • The perlid stonefly Brahmana flavomarginata Wu, originally described from China from the male adult, is described using reared male and female adults and nymphs from Vietnam. The male adult of B. flavomarginata is distinguished from its congeners by the blackish-brown body color and distinct head marking, hemitergal triangular chitin plates, and a median semicircular smooth subgenital plate (hammer) on the abdominal sternum IX. The female adult has a large and round subgenital plate which extends to the posterior margin of the abdominal sternum X. The nymph can be distinguished by the relatively small compound eyes and the body covered by many long stout setae and short golden brown hair-like setae. This species is known in southwestern China (Yunnan Province) and northern Vietnam (Lao Cai Province, Cao Bang Province).

원발성 간암환자에서 관찰된 $^{99m}Tc$-DISIDA의 비장 섭취 1예 (A Case of Hepatoma with Hot Uptake of $^{99m}Tc$-DISIDA to Spleen)

  • 이예봉;김성진;박언휘;방인숙;김홍주;윤성철;이원재
    • 대한핵의학회지
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    • 제27권1호
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    • pp.140-143
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    • 1993
  • We report a case of hepatoma which had a suggested splenic metastasis in a 64 year-old male patient. Hepatoma proved by abdominal CT (Computed Tomography) and considerable accumulation of $^{99m}Tc$-DISIDA was noted in a enlarged spleen. We suggests the splenic uptake of the radionuclide corresponded to the diffuse metastasis of hepatoma to spleen.

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응력해석을 통한 풍력 발전기용 피치/요 베어링 설계 검증 (Design evaluation of wind turbine pitch/yaw bearings by contact stress analysis)

  • 가재원;김재동;남용윤;임채환;박영준;방제성;이영신
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2011년도 추계학술대회 초록집
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    • pp.43.2-43.2
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    • 2011
  • Wind turbine pitch/yaw bearings are relatively big and have different operating conditions like very heavy load to support compared with widely used industrial bearings. Once pitch/yaw bearings failed, according to their special surroundings, serious damages like higher repair costs and additional costs by stopped electricity generation are occur. Therefore, pitch/yaw bearings must be designed to have enough strength and fatigue life under actual operating conditions. In this study, with finite element analysis, it was investigated that stress distribution between rolling elements and raceway and comparatively analyzed using widely used guideline (NREL DG03). Design parameters of wind turbine pitch/yaw bearings are also analyzed, and it could be used as reference for the large bearing design field.

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