• 제목/요약/키워드: Adverse conditions

검색결과 533건 처리시간 0.023초

지중배전선로의 다회로차단기 운영방안 연구 (The Study of Multi-Circuit Breaker Coordination in the Underground Distribution Line)

  • 조남훈;하복남;이흥호
    • 대한전기학회논문지:전력기술부문A
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    • 제49권4호
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    • pp.143-151
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    • 2000
  • Electric power distribution feeders are susceptible to faults caused by a variety of situations such as adverse weather conditions, tree contacts, equipment failure, accidents, etc. Distribution circuit faults result in a number of problems related to the reliability of service and customer power quality. In the distribution line, the permanent interruption of customer service resulting from a blown fuse or a recloser lockout was the only factor which was used to determine service reliability. On underground distribution line, the serving of cables by earth-moving equipment is a prevalent cause of faults and the most cable faults quickly develop into bolted current. we introduce th multi-circuit breaker coordination methods in the Underground Distribution Line.

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청각모델을 이용한 음성신호의 특징 추출 방법에 관한 연구 (Speech Feature Extraction Using Auditory Model)

  • 박규홍;김영호;정상국;노승용
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 G
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    • pp.2259-2261
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    • 1998
  • Auditory Models that are capable of achieving human performance would provide a basis for realizing effective speech processing systems. Perceptual invariance to adverse signal conditions (noise, microphone and channel distortions, room reverberations) may provide a basis for robust speech recognition and speech coder with high efficiency. Auditory model that simulates the part of auditory periphery up through the auditory nerve level and new distance measure that is defined as angle between vectors are described.

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지중배전선로의 고장전류 크기 및 보호협조분석 (Ananalzing fault current and Protective coordination in the underground line)

  • 조남훈;하복남;이중호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1998년도 하계학술대회 논문집 C
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    • pp.932-934
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    • 1998
  • Electric power distribution feeders are susceptible to faults caused by a variety of situations such as adverse weather conditions, tree contacts, equipment failure, accidents, etc. Distribution circuit faults result in a number of problems related to the reliability of service and customer power quality. In the past, the permanent interruption of customer service resulting from a blown fuse or a recloser lockout was the only factor which was used to determine service reliability. So we developed KODAS(Korea Distribution Automation System) with successful and had fieid-testing of Distribution Automation System in last three years at Kang-dong Branch Office. In performing the project, KEPRI has gained valuable experience, through dealing with many difficult problem. This paper is depicted about the circuit breaker coordination problems in the Underground for the Distribution Automation Feeder.

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균일 두께의 자성유체 피막이 있는 평면 벽을 향하는 2차원 정체 유동 (TWO-DIMENSIONAL STAGNATION FLOW TOWARD A PLANE WALL COATED WITH MAGNETIC FLUID OF UNIFORM THICKNESS)

  • 고형종;김경훈;김세웅
    • 한국전산유체공학회지
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    • 제12권4호
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    • pp.20-27
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    • 2007
  • Two-dimensional stagnation flow toward a plane wall coated with magnetic fluid of uniform thickness is investigated. The flow field is represented as a similarity solution of the Navier-Stokes equation for this incompressible laminar flow. The resulting third order ordinary differential equation is solved numerically by using the shooting method and by determining two shooting parameters so as to satisfy the boundary and interface conditions. Features of the flow including streamline patterns are investigated for the varying values of density ratio, viscosity ratio, and Reynolds number. An adverse flow with double eddy pair in magnetic fluid region is found to emerge as the Reynolds number becomes higher than a threshold value. The results for the interface velocity, interface and wall shear stress, and boundary layer and displacement thickness are also presented.

모바일 환경에서 고객 맞춤형 정보서비스를 위한 MoSA-CRM 시스템 (MoSA-CRM System for Customer-Oriented Information Service Provision in Mobile Environment)

  • 홍장의;김종필
    • Journal of Information Technology Applications and Management
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    • 제13권4호
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    • pp.155-165
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    • 2006
  • Along with the evolution of wireless internet environment, information services in mobile internet are being explosively increased. However, due to the high expense for the use of those services, it is not easy to collect the devoted customers. In order to overcome the adverse conditions, the service should be supported by a strategic application system which facilitates easier and fast service for customer's information needs than that of traditional on-line internet. In this paper, we investigate the strategy how to provide the information service under the customer satisfaction, and also consider some ways of personalization of information service and information provision in real-time. As a result of the works, we develop a system, MoSA-CRM(Mobile Service Application based on CRM) to support customer-oriented information service. We believe that the MoSA-CRM system can provide some benefits for information providers in mobile e-commerce market such as flexibility in business strategy, systematic customer relationship management, and growth in financial ability.

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The Research about Aerial photographing system(PKNU No.2) development

  • Kim, Ho-Yong;Choi, Chul-Uong;Lee, Eun-Khung;Jun, Sung-Woo
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2003년도 Proceedings of ACRS 2003 ISRS
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    • pp.110-112
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    • 2003
  • The researchers, who seek geological and environmental information, depend on the remote sensing and aerial photographic datum from various commercial satellites and aircraft. However, the adverse weather conditions and the expensive equipment can restrict that the researcher can collect their data anywhere and any time. To allow for better flexibility, we have developed a compact, a multispectral automatic Aerial photographic system. This system's Multi-spectral camera can catch the visible (RGB) and infrared (NIR) bands (3032${\ast}$2008 pixel) image. Our system consists of a thermal infrared camera and automatic balance control, and it managed and controlled by a palm-top computer. And it includes a camera gimbals system, GPS receiver, weather sensor and etc. As a result, we have successfully tested its ability to acquire aerial photography, weather data, as well as GPS data, making it a very flexible tool for environmental data monitoring.

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An Approach to Improve Romanian Geological Repository Planning

  • Andrei, Veronica;Prisecaru, Ilie
    • Nuclear Engineering and Technology
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    • 제48권2호
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    • pp.495-504
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    • 2016
  • International standards recommend typical phases to be included within any national program for the development of a geological repository dedicated to disposal of the high level radioactive wastes generated in countries using nuclear power. However, these are not universally applicable and the content of each of these phases may need to be adapted for each national situation and regulatory and institutional framework. Several national geological repository programs have faced failures in schedules and have revised their programs to consider an adapted phased management approach. The authors have observed that in the case of those countries in the early phases of a geological repository program where boundary conditions have not been fully defined, international recommendations for handling delays/failures in the national program might not immediately help. This paper considers a case study of the influences of the national context risks on the current planning schedule of the Romanian national geological repository. It proposes an optimum solution for an integrated response to any significant adverse impact arising from these risks, enabling sustainable program planning.

농산물 골판지포장상자의 수송 중 진동에 의한 압축강도 변화 (Effect of Vibration during Distribution Process on Compression Strength of Corrugated Fiberboard Containers for Agricultural Products)

  • 조중연;신준섭;김종경
    • 한국펄프종이공학회:학술대회논문집
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    • 한국펄프종이공학회 2008년도 춘계학술대회
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    • pp.290-307
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    • 2008
  • The aim of this study was to estimate adverse effect on compression strength of corrugated fiberboard containers due to vibration during distribution process. Distribution environment such as road conditions and compression strength of corrugated fiberboard containers for selected agricultural products were studied. We found that increasing humidity does not effect significantly on natural frequencies of boxes, but results in accelerative effect to decrease compression strength of boxes. Box structures and product types also effect on loss of compression strength greatly.

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석유탄화수소를 이용한 단세포단백질의 생산에 관한 연구 3 (Production of Single-Cell Protein on Petroleum Hydrocarbon)

  • 변유량;권태완
    • 미생물학회지
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    • 제9권3호
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    • pp.95-102
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    • 1971
  • The growth characteristics of Candida tropicalis KIST 351 on gas oil substrate under different culture conditions were investigated and the preliminary animal feeding experiments using this yeast as a partial substitute of fish meal was also conducted. The yeast assimilates effectively n-paraffins in gas oil ranging from $C_{16}$ to $C_{16}$ with its maximum cell growth at $33^{\circ}C$ and pH 5.5 with aeration of 3 vvn and agitation of 900 rpm. The optimal concentrations of nitrogen sources, $HK_2PO_4$ and $Na_2HPO$ were 4, 2 and 0.5g/1, respectively. Ferrous sulfate, manganese sulfate and zinc sulfate showed positive effect to cell growth with the optimal range of 5-10 ppm. In the feeding experiment with 3 and 5% incorporation of the gas oil grown yeast, neither adverse effects on growth of chicks nor toxic effect were observed. Protein content of the dried cell was 58.8% and its amino acid composition compared well with other single-cell protein products and FAO reference protein.

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Differentially expressed genes of Acanthamoeba castellanii during encystation

  • Moon, Eun-Kyung;Chung, Dong-Il;Hong, Yeon-Chul;Kong, Hyun-Hee
    • Parasites, Hosts and Diseases
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    • 제45권4호
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    • pp.283-285
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    • 2007
  • To examine the expressed gene profile during encystation of Acanthamoeba castellanii Castellani, we used differentially expressed gene (DGE) screening by RT-PCR with 20 sets of random primers. From this analysis, we found that approximately 16 genes showed up regulation during encystation. We chose 6 genes, which had relatively higher expression levels, for further investigation. Based on homology search in database, DEG2 showed 55% of similarity with xylose isomerase, DEG9 showed 37% of similarity with Na P-type ATPase, and DEG14 showed 77% of similarity with subtilisin-like serine proteinase. DEG3 and DEG26 were identified as hypothetical proteins and DEG25 exhibited no significant similarity to any known protein. Encystation of Acanthamoeba has been suggested to be a process to resist adverse environmental or nutritional conditions. Further characterization studies of these genes may provide us with more information on the encystation mechanism of Acanthamoeba.