• 제목/요약/키워드: Lead Length

검색결과 499건 처리시간 0.025초

지중송전계통에서 불평형 구성요소에 따른 과도현상 해석 및 평가 (Transient Phenomena Analysis and Estimation According to Unbalance Factors on Underground Power Cable Systems)

  • 정채균;이종범;강지원;이동일
    • 대한전기학회논문지:전력기술부문A
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    • 제54권8호
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    • pp.410-417
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    • 2005
  • This paper analyses the transient phenomena against single line to ground fault and lightning surge on underground power cable systems. For analysis in various fault conditions, several actual underground power cable systems are modeled using ATP In ground fault, the transient characteristic of the conductor and the sheath according to the fault current and the installation types of CCPU are analysed. In lightning surge strokes, the various unbalanced conditions including the length of crossbonded lead, the breakdown of CCPU and distance unbalance are considered. This paper is expected to contribute the establishment of proper protection methods against transients on underground power cable systems.

Long noncoding RNA involvement in cancer

  • Maruyama, Reo;Suzuki, Hiromu
    • BMB Reports
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    • 제45권11호
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    • pp.604-611
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    • 2012
  • Recent advances in genome and transcriptome analysis have enabled identification of numerous members of a new class of noncoding RNA, long noncoding RNA (lncRNA). lncRNAs are broadly defined as RNA molecules greater than 200 nt in length and lacking an open reading frame. Recent studies provide evidence that lncRNAs play central roles in a wide range of cellular processes through interaction with key component proteins in the gene regulatory system, and that alteration of their cell- or tissue-specific expression and/or their primary or secondary structures is thought to promote cell proliferation, invasion and metastasis. The biological and molecular characteristics of the large majority of lncRNAs remains unknown, and it is anticipated that improved understanding of the roles played by lncRNAs in cancer will lead to the development of novel biomarkers and effective therapeutic strategies.

지수 비재고비율을 갖는 효율적 부분비재고시스템에 관한 연구 (A Stochastic Partial Backorder Inventory System with a Exponential Backorder Ratio)

  • 이강우
    • 한국경영과학회지
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    • 제21권1호
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    • pp.71-80
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    • 1996
  • This paper presents a stochastic partial inventory model for the situation in which demand is deterministic, lead time follows normal distribution and backorder ratio during the stockout period decreases exponentially according to the length of backorder period. In this situation, an objective function is formulated to minimize the average annual cost, which is the sum of the ordering, carrying time-proportional backordering, quantity-proportional backordering and lost sales costs. And then the procedure of iterative solution method for the model is developed to find optimal reorder point and order quantity and numerical example to illustrate the proposed method is presented.

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GIS 내 금속입자의 부상전압과 부분방전특성 연구 (Lift-Off Voltage and Partial Discharge Characteristics of Free Metallic Particles in GIS)

  • 윤진열;한상옥
    • 대한전기학회논문지:전기물성ㆍ응용부문C
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    • 제48권2호
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    • pp.127-132
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    • 1999
  • Both motion of free metallic particles from which most GIS internal failures are caused and partial discharges from the particles were examined using EHV GIS test chamber. Effects from particle length and gas pressure which are main factors to lead to breakdown failure were investigated theoretically and experimentally. Magnitude of both lift-off voltage and partial discharge inception voltage were measured respectively and, through these measurements, this paper showed the possibility of predicting breakdown fault and of taking action to prevent the fault in advance. The measurement of partial discharge when the particles began to move could be adopted to decide minimum sensitivity in developing predictive diagnostic equipments. Both the amount of apparent discharge and real discharge in GIS were examined theoretically and experimentally, then experimental results were analyzed on the basis of the theory.

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지중송전계통에서 불평형요소에 따른 뇌과전압 해석 (Analysis of lightning overvoltage with unbalanced element in Underground Transmission Cable System)

  • 강지원;이동일;김재승;김양상;정채균;이종범
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2005년도 제36회 하계학술대회 논문집 A
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    • pp.718-720
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    • 2005
  • This paper analyses the transient phenomena against lightning surge on underground power cable systems. For analysis, several actual underground power cable systems are modeled using ATP. In lightning surge strokes, the various unbalanced conditions including the length of crossbonded lead, the breakdown of CCPU and distance unbalance are considered. This paper is expected to contribute the establishment of proper protection methods against transients on underground power cable systems.

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실시간 곡면 가공에 관한 제어 알고리즘 및 하드웨어 연구 (Realtime control algorithm and hardware for machining curved surfaces)

  • 정승권;권욱현
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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    • pp.1320-1323
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    • 1996
  • This paper describes an interpolation method for a parametric surface. A parametric surface is approximated to triangular mesh surfaces and then the basic paths are achieved. As the generated path is a series of linear segments, this algorithm can be easily adapted to general NC controllers. The generated paths have minimal transfer length and are gouge-free within the approximation tolerance. The problems, induced when the paths are represented by linear segments, are overcome without making any path deviation by this algorithm. This algorithm saves machining time by eliminating overdetermined tool paths and keeping the desired average feedrate, which improve productivity and lead to lower production costs.

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자기상관 공정에 대한 누적합관리도에서 설계모수 값의 결정 (A note on CUSUM design for autocorrelated processes)

  • 이재준;이종선
    • 품질경영학회지
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    • 제36권4호
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    • pp.87-92
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    • 2008
  • It is common to use CUSUM charts for detecting small level shifts in processes control, in which reference value(k) and decision interval(h) are the design parameters to be determined. To control process with autocorrelation, CUSUM charts could be applied to residuals obtained from fitting ARIMA models. However, constant level shifts in processes lead to varying mean shifts in residual processes and thus standard CUSUM charts may need to be modified. In this paper, we study the performance of CUSUM charts with various design parameters applied to autocorrelated processes, especially focussing on ARMA(1,1) models, and propose how they can be determined to get better performance in terms of the average run length.

제지식 판상엽의 공정 개선 연구 (A study on the Process Improvement of Papermade Reconstituted Tobacco)

  • 김영호;한영림;김근수;김대종
    • 한국연초학회지
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    • 제22권2호
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    • pp.164-169
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    • 2000
  • The reconstituted tobacco leaves(RTL) playa major part in the control of the low density and tar cigarette. Reconstituted tobacco manufactured by the papermaking process has much higher filling power than homogenized tobacco manufactured by slurry and rolling process. Fragile reconstituted tobaccos are liable to lead to small particles detrimental for filling power so they must be properly flexible. This work was conducted to determine the effect of CaCO$_3$ addition in paper-making process on the filling power and the flexibility of the reconstituted tobacco and to obtain the fundamental informations for improving the quality of domestic reconstituted tobacco. We analyzed the wood fiber species, the filler level, the fiber length, the fineness level and observed the surface of the RTL. From the obtained results, we could determine that foreign reconstituted tobacco was manufactured by blending softwood with hardwood and over 8% of calcium carbonate at the addition level. The domestic RTL has much higher fine fiber level by 23.2 % than that of foreign, so the refining treatment process and the condition must be reoptimized for the improvement of RTL quality.

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서양복식사에 나타난 금제고찰 (A Review on the Sumptuary Laws of Western Costume)

  • 김인숙
    • 대한가정학회지
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    • 제19권3호
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    • pp.1-9
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    • 1981
  • The object of this study lies in reviewing of the western costume history in the light of the negative regulations concerning costumes and adornments. Readings related with the subject lead to the following findings; 1. the principal purpose of the sumptuary laws has relationship with the social stratification of the feudalism and the frequency of their occurrence is related with the formation of feudal system, its decline, the appearance of imperial regimes and the start of civil revolutions. 2. Sumptuary regulations spread westward with the flow of civilization, eg., in the sequence of Italy, swiss, France, Britain and new world. 3. Sumptuary laws are also found in abundance in the english colonies of America, and their object seems to be rather of the moral concern than class distinction of economical restriction.4. The reviewed sumptuary regulations are concerned with : A. Material gold or silver clothes, silks, ermine, marten or miniver furs, velvets, laces and embroies. B. Colors-Purple, scarlet and red. Other colors do not show consistent pattern of color-status symbol; C. Form-Length and width of headdresses, shoes, collars, trains or hoops. E. numbers of dresses allowed to be worn.

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중소기업 마케팅.유통 지원을 위한 협력상거래 포탈 설계 및 구현 (Design and Implementation of c-Commerce Portal of Small and Medium Enterprises for Marketing)

  • 안요찬;서중석
    • Journal of Information Technology Applications and Management
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    • 제11권1호
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    • pp.175-187
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    • 2004
  • Many companies have integrated their internal processes with the aid of information technology. Now the focus is on interconnecting trading partners. Collaborative commerce (also known as c-Commerce) has a key role. It is not just about making it easier for business to communicate. It is about by breaking down barriers along the entire length of the supply chain. Some c-Commerce links are permanent, others get established when and where they are needed. c-Commerce is helping business in electronic supply chains to improve product delivery while cutting costs, to strengthen relationships and to reduce lead time. In this paper, we propose the concept of collaborative commerce, and design and implement Collaborative Commerce Portal (CCP) system of small and medium enterprise for marketing support. The technical definition of CCP is set of all technical elements can do collaborative commerce between small and medium enterprises with Internet or Internet. The target information of CCP includes usual and unusual information and all other information of companies used as process events. Through this, it enhances efficiency of business processes, core information sharing and marketing activation.

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