• 천문학회지
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• 제17권1호
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• pp.23-36
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• 1984

From the PDS scanning, isophote maps and surface luminosity distributions for the late type spiral galaxy NGC 6946 were obtained. Surface luminosity distribution showed that this galaxy can be classified as the Freeman's type II, and the deep spheroidal component was caused as a result of the ring structure in the central part of NGC 6946. Physical parameters-total magnitude ($M_T^B$), effective radius ($R_e^*$), central surface magnitude $U(0)_{CD}$, length scale (${\alpha}^{-1}$), disk-to-bulge ratio (D/B) and mass-to-luminosity ratio (M/L)-were also calculated, and the results show that NGC 6946 belongs to Sc I type galaxy according to the DDO classification, and is to be a fair sample of classification statge T=6.

• 품질경영학회지
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• 제23권4호
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• pp.180-189
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• 1995

Today, as globalization continues and international trading blocks are formed, world markets are intensely competitive and abound in product variety, volume, complexity and environmental management. Specifically, green consumer's needs and expectations are changing and diversifying, resulting in a changed global environment for industry. Due to these changes, domestic companies are striving to achieve the Environmental Management System (ISO 14000) certification. This is considered a basis step in meeting the guiding principle and practice of ISO/TC 207/SC 3 resolution. In this paper, we will present three type(I, II, III) of Environmental Labelling programs to build a model for environmental management system by analysing practitioner and stakeholder. After companies establish an ISO 9000 quality system these companies should focus on improve toward their own Environmental Labelling program and continue to build ISO 14000.

• 한국환경과학회지
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• 제1권2호
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• pp.69-80
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• 1992

Effects of light on leaf senescence of Phseolus vulgaris were investigated by measuring the disassembly of chlorophyll-protein complexes in detached leaves which had been kept in the dark or under light. The loss of chlorophyll accompanied by degradation of chlorophyll- protein complexes. PSI (photosystem I) complex containing LHCI (light harvesting complex of PSI) apoproteins was rapidly decreased after the early stage of dark-induced senescence. RC(reaction center)-Cores was slightly increased until 4 d and slowly decreased thereafter. As disassembly of LHCII trimer progressed after the late stage of senescence, there was a steady increase in the relative amount of SC(small complex)-2 containing LHCII monomer. On the other hand, white and red light adaptation caused the structural stability of chlorophyll-protein complexes during dark-induced senescence. Particularly, red light was more effective in the retardation of LHCII breakdown than white light, whereas white light was slightly effect in protecting the disassembly of PSI complex compared to red light. These results suggest, therefore, that light may be a regulatory factor for stability of chlorophyll-protein complexes in the senescent leaves.

• 정보처리학회논문지D
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• 제9D권5호
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• pp.837-846
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• 2002

컴포넌트 개발 시에 속성과 행위에 대한 공용성과 가변성을 분석하여 재사용과 확장성을 제공할 수 있다. 그러므로 공용성과 가변성이 분석된 컴포넌트는 기능과 적합성의 불일치를 줄이고자하는 목적에서 사용하게 된다 본 논문에서는 영역에 의하여 존재하는 컴포넌트의 공용성과 가변성을 분석해서, 컴포넌트의 기능을 행위분석에 의하여 추출하였다. 이와 같은 분석에 의하여 컴포넌트의 재사용과 확장성을 연구하고자 한다.

• 산업경영시스템학회지
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• 제17권31호
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• pp.115-123
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• 1994

Group scheduling, which is a kind of operations scheduling based on the GT concept is analyzed in a multi-stage manufacturing system. The purpose of this research is to develop and evaluate a heuristic algorithm for determining gro up sequence and job sequence within each group to minimize a complex cost function, i.e. the sum of the total pe-nalty cost for tardiness and the total holding cost for flow time, in a multi-stage manufacturing system with group setup time dependent upon group sequence. A heuristic algorithm for group sc heduling is developed, and a numerical example is illustrated. For the evaluation of the pro-posed heuristic algorithm, the heuristic solution of each of 63 problems is compared with that of random scheduling. The result shows that the proposed heuristic algorithm provides better solution in light of the proposed cost function.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 C
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• pp.1848-1850
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• 1996

A Couette Charger was used to simulate streaming electrification process in transformer. This paper describes the electrification characteristics of the energized and unenergized Couette Charger. By applying low frequency and high voltage across the cylinder of the Couette Charger, the measured short circuit current$i_{sc}$) is compared with the measured values of unenergized Couette Charger. As a result, short circuit current was increased with voltage.

• Asian-Australasian Journal of Animal Sciences
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• 제24권3호
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• pp.429-438
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• 2011

Mastitis is characterized by physical, chemical and bacteriological changes in the milk and pathological changes in the glandular tissue of the udder and affects the quality and quantity of milk. The bacterial contamination of milk from the affected cows render it unfit for human consumption and provides a mechanism of spread of diseases like tuberculosis, sore-throat, Q-fever, brucellosis, leptospirosis etc. and has zoonotic importance. Somatic cell count (SCC) is a useful predictor of intramammary infection (IMI) that includes leucocytes (75%) i.e. neutrophils, macrophages, lymphocytes, erythrocytes and epithelial cells (25%). Leucocytes increase in response to bacterial infection, tissue injury and stress. Somatic cells are protective for the animal body and fight infectious organisms. An elevated SCC in milk has a negative influence on the quality of raw milk. Subclinical mastitis is always related to low milk production, changes to milk consistency (density), reduced possibility of adequate milk processing, low protein and high risk for milk hygiene since it may even contain pathogenic organisms. This review collects and collates relevant publications on the subject.

• 대한화학회지
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• 제58권1호
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• pp.44-48
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• 2014

Catalytic performance of Lewis acids have been investigated in the synthesis of 1,2,3,4-tetrahydroquinolines via cyclocondensation reaction of aniline derivatives with cyclic enol ethers such as 3,4-dihydro-2H-pyran and 2,3-dihydrofuran. The catalytic activity of various of these catalysts in different solvents was compared with other classical catalysts such as KSF clay (1.5 g), $InCl_3$ (10-20 mol%), $ZrOCl_2$ (10 mol%), $Sc(OTf)_3$ (3 mol%), PANI-$InCl_3$ (10 mol%), $I_2$ (20 mol%), $InCl_3$ (5 mol%), 4-npa (25 mol%) and Cellulose-$SO_3H$ (0.03 g).

• 전력전자학회:학술대회논문집
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• 전력전자학회 2013년도 전력전자학술대회 논문집
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• pp.68-69
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• 2013

태양광 효율 기준 규정인 IEC의 EN50530에서는 태양광발전용 PCS(Power Conditioning System)의 성능평가를 위하여 PV Simulator를 사용하도록 규정하고 있다. PV Simulator는 전압원과 전류원의 복합적인 특성을 갖는 PV array의 전원특성을 구현하여야 한다. 즉, $I_{SC}$ 동작점 부근에서는 전류원의 형태로 동작하고, $V_{OC}$의 동작점 부근에서는 전압원의 형태로 동작하여야 한다. 또한 MPP 운전점에서는 전류원도 아니고 전압원도 아닌 중간적인 동작 특성을 갖는다. 본 논문에서는 PV Simulator의 출력방식을 전압원형과 전류원형으로 구현하는 제어시스템의 동작 특성을 실험을 통하여 비교 연구한다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 1995년도 제4회 학술강연회논문집
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• pp.23-29
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• 1995

Fafbric 4종, 수지2종과 상용화된 프리프레그 2종에 대한 내열특성에 관하여 비교 연구 하였다. Fabric의 특성은 알려진 바와 같이 PAN계 카본 fabric의 경우 내삭마성은 우수하나 단열성능이 떨어지고, Rayon계의 경우는 그 반대이다. 공정성면에서는 rayon spun yarn으로 제직한 경우가 가장 우수한 것으로 나타났다. Spun PAM으로 제직한 경우는 직조후 탄화공정을 채택함으로써. 노즐재료로서 PAN계 탄소섬유의 사용을 가능하게 하였지만 즉 공정성은 좋으나 단열성 및 내삭마성 모두가 떨어졌다. F940수지의 경우는 SC1008과 페놀수지의 화학적특성은 다소 차이가 있으나 물리적특성이나 열적특성은 거의 유사한 것으로 나타났다. 프리프레그의 제조는 각수지와 Fabric의 조건에 맞게 R/C, V/C를 조정하여 코팅하였다. 토오치 테스트등 결과들을 종합해보면 전체적인 노즐재료로서의 성능은 아직은 Rayon계 카본이 우수한것으로 판단할수 있으나, 보다 정확한 평가를 위해서는 실제 노즐 테스트가 필요하다.