• 제목/요약/키워드: Reverse

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Schottky Body Diode를 집적하여 향상된 Reverse Recovery 특성을 가지는 50V Power MOSFET (50V Power MOSFET with Improved Reverse Recovery Characteristics Using an Integrated Schottky Body Diode)

  • 이병화;조두형;김광수
    • 전기전자학회논문지
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    • 제19권1호
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    • pp.94-100
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    • 2015
  • 본 논문에서는 U-MOSFET 내부의 기생 body 다이오드(PN diode)를 쇼트키 body 다이오드(Schottky body diode)로 대체한 50V급 전력 U-MOSFET을 제안하였다. 쇼트키 다이오드는 PN 다이오드와 비교 시, 역 회복 손실(reverse recovery loss)을 감소시킬 수 있는 장점을 가지고 있다. 따라서 전력 MOSFET의 기생 body 다이오드를 쇼트키 body 다이오드를 대신함으로써 역 회복 손실을 최소화 할 수 있다. 제안된 쇼트키 body 다이오드(Schottky body diode) U-MOSFET(SU-MOS)를 conventional U-MOSFET(CU-MOS)와 전기적 특성을 비교한 결과, 전달(transfer) 및 출력(output)특성, 항복(breakdown)전압 등 정적(static) 특성의 변화 없이 감소된 역 회복 손실을 얻을 수 있었다. 즉, 쇼트키 다이오드의 폭(width)이 $0.2{\mu}m$, 쇼트키 장벽 높이(Schottky barrier height)가 0.8eV일 때 첨두 역전류(peak reverse current)는 21.09%, 역 회복 시간(reverse recovery time)은 7.68% 감소하였고, 성능지수(figure of merit(FOM))는 35% 향상되었다. 제안된 소자의 특성은 Synopsys사의 Sentaurus TCAD를 사용하여 분석되었다.

코카인으로 유도된 행동과다, 역내성 및 Dopamine 수용체 초과민성에 미치는 인삼 Saponin의 효과 (Effects of Ginseng Saponins on Cocaine-Induced Hyperactivity, Reverse Tolerance and Dopamine Receptor Super-sensitivity in Mice)

  • 김학성;정주연
    • Journal of Ginseng Research
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    • 제19권2호
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    • pp.101-107
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    • 1995
  • The present study was undertaken to examine the effects of ginseng saponins [ginseng total saponin (GTS), protopanaxadiol saponin (PD) and protopanaxatriol saponin (PT)] on the hyperactivity, reverse tolerance and dopamine receptor super-sensitivity induced by cocaine. A single treatment with cocaine produced hyperactivity. Repeated administration of cocaine developed reverse tolerance and dopamine receptor super-sensitivity was also developed in reverse tolerant mice which had received the same cocaine. The hyperactivity and the developments of reverse tolerance and dopamine receptor super-sensitivity by cocaine were inhibited by ginseng saponins. From these results, it is proposed that ginseng saponins may be useful for the prevention and therapy of the adverse actions of cocaine. In addition, the rank order of inhibitory potential was observed as PT>GTS>PD. Key words Cocaine, hyperactivity, reverse tolerance, dopamine receptor super-sensitivity, ginseng saponins.

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환경친화적 물류시스템의 환경물류 정보화 요인 연구 (A Study of the Reverse Logistics Information Factors for Environmental Conscious Logistics System)

  • 김현수
    • 산업경영시스템학회지
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    • 제27권4호
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    • pp.59-68
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    • 2004
  • Recently, shifting channel power is forcing supply chain to take back products. As you can imagine returned product has always been a problem for all parties in the supply chain due to the disruption in operations and a headache in processing returned products. Therefore, every member of supply chain should respond to reverse logistics activities particularly for the return handling process. Under such a strong demand of efficient and cost effective reverse logistics activities, particularly for the return handling process, the information system should be implemented and participated in intensively. This study analyzed the reverse logistics information factors for environmental conscious logistics system limited to returns from customers/consumers. The results provide reverse logistics information factors based on the return handling process which can be used as benchmarking for companies seeking implementation of an efficient return handling system.

Component-Based Software Architecture for Biosystem Reverse Engineering

  • Lee, Do-Heon
    • Biotechnology and Bioprocess Engineering:BBE
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    • 제10권5호
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    • pp.400-407
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    • 2005
  • Reverse engineering is defined as the process where the internal structures and dynamics of a given system are inferred and analyzed from external observations and relevant knowledge. The first part of this paper surveys existing techniques for biosystem reverse engineering. Network structure inference techniques such as Correlation Matrix Construction (CMC), Boolean network and Bayesian network-based methods are explained. After the numeric and logical simulation techniques are briefly described, several representative working software tools were introduced. The second part presents our component-based software architecture for biosystem reverse engineering. After three design principles are established, a loosely coupled federation architecture consisting of 11 autonomous components is proposed along with their respective functions.

ON ORTHOGONAL REVERSE DERIVATIONS OF SEMIPRIME 𝚪-SEMIRINGS

  • Kim, Kyung Ho
    • 충청수학회지
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    • 제35권2호
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    • pp.115-124
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    • 2022
  • In this paper, we introduce the notion of orthogonal reserve derivation on semiprime 𝚪-semirings. Some characterizations of semiprime 𝚪-semirimgs are obtained by means of orthogonal reverse derivations. We also investigate conditions for two reverse derivations on semiprime 𝚪-semiring to be orthogonal.

Reverse Bending을 통한 CTOD 시험 예비균열 형상균일화에 관한 연구 (A study on reduction of pre-crack deviation in CTOD specimen using reverse bending method)

  • 정세환;박동환;김현수;신상범;박태종
    • Journal of Welding and Joining
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    • 제33권2호
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    • pp.62-68
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    • 2015
  • This study investigates the appropriate range of reverse bending load for the CTOD test of thick weld by observing improvement of pre-crack shape and determination of the limit applicable load. In order to do it, the effect of the amount of the reverse bending load on the maximum deviation of the pre-crack length was investigated by the extensive tests, and the variation of plastic zone size in way of the crack tip under reverse bending load were evaluated by FEA. With the results obtained by the experiments and FEA, the proper range of reverse bending load was suggested. The effectiveness of the reverse bending method was verified by examining the pre-crack straightness after CTOD tests of thick weld specimens with various thickness and strength.

FFS 모드에서 Reverse Twist가 구동전압에 미치는 영향에 관한 연구 (Study on the Effect of the Operation Voltage according to the Reverse Twist for the fringe Field Switching (FFS) Mode)

  • 김미숙;정연학;신승민;김향율;김서윤;임영진;이승희
    • 한국전기전자재료학회논문지
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    • 제18권11호
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    • pp.1033-1037
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    • 2005
  • We have studied on the effect of the operation voltage according to the reverse twist for the different fringe field switching (FFS) structure. The FFS structure with a vertically patterned edge of the pixel electrode (VPP) has lower operation voltage comparing to the one with a horizontally patterned edge of the pixel electrode (HPP). The reason is like that the number of the pattern of the pixel edge for the VPP structure is one third comparing with the HPP structure and thus, there is small reverse twist area for the VPP structure. Actually, the reverse twist disturbs the twist of LC near adjacent active area, result that LCs near there have the unstable dynamics. That is, the operation voltage increases as the reverse twist area increases. Therefore, it is very important to design pixel electrode with a small reverse twist region for the FFS mode.

The Value of Reverse Mortgage Loans: Case Study of the Chinese Market

  • Wang, Ping;Kim, Ji-Pyo
    • The Journal of Asian Finance, Economics and Business
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    • 제1권4호
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    • pp.5-13
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    • 2014
  • This study contributes to addressing the problem of an aging population by providing important information that determines feasible monthly payments for the clients of Chinese reverse mortgage products and by promoting the implementation of reverse mortgages in China. The variables used in this study include mean values obtained from time series data, of the rate of increase of housing prices, and the probability value, interest rate, and mortality rate obtained through the geometric Brownian motion (GBM). For mortality rates, China Life Insurance female mortality rates (2000-2003) were used. This study aims to apply the main variables that affect reverse mortgage products in a monthly payment model based on Chinese financial market conditions, and determine loan values. In this study, Shanghai's reverse mortgage monthly payments, by age levels, were calculated through the loan-to-value (LTV) and payment (PMT) methods to evaluate the value of the reverse mortgages. Based on the optimal combination of the three factors of payment amount, loan interest rates, and the level of acceptance of prices, efforts must be made to extract the best value for the elderly. Only in this way can the interests of both lenders and borrowers be protected, by increasing the market share and economies of scale of the reverse mortgage industry and effectively improving the living standards of the elderly.

A STUDY OF THE EFFECT OF AN ANTI-ROTATIONAL INNER POST SCREW SYSTEMS ON ABUTMENT SCREW LOOSENING FOR SINGLE IMPLANT : PART 1

  • Choi, Sun-Young;Lee, Jai-Bong
    • 대한치과보철학회지
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    • 제45권3호
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    • pp.345-353
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    • 2007
  • Statement of problem. Implant abutment screw joints tend to loosen under clinical conditions. Abutment screw loosening results in loss of preload in function. Purpose. Anti-rotational inner post screw (ARIPS) systems were compared with conventional abutment screws to reduce screw loosening. Reverse torque values were evaluated. Material and methods. 32 implant assemblies (Warentec, Co, Ltd, Seoul, Korea) were organized as the 30-Ncm-torque conventional groups and 30-Ncm-torque ARIPS groups in external and internal system. The specimens were tested to 106 cycles at a load of 200N. Preload reverse torque, postload reverse torque, and the ratio of postload reverse torque to preload reverse torque were evaluated. The data were analyzed with unpaired t-test in external and internal systems. Results. In the ratio of postload reverse torque to preload reverse torque, the ARIPS groups showed significant differences than the conventional screw group in both external and internal system. Conclusion. Within the limitations of this study, abutment screw loosening was effectively reduced using ARIPS system.