• 제목/요약/키워드: Overall efficiency

검색결과 2,370건 처리시간 0.036초

Biomass Conversion Efficiencies of Fish Pond Fertilization and Feed Supplementation

  • Mahboob, Shahid;Sheri, A.N.
    • Asian-Australasian Journal of Animal Sciences
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    • 제11권2호
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    • pp.192-195
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    • 1998
  • Biomass conversion efficiencies (B.C.E) of six fish species viz, Catla catla, Labeo, rohita, Cirrhina mrigala, Hypophthalmicthys molitrix, Ctenopharyngodon idella and Cyprinus carpio cultured under artificial feed (T1), broiler manure (T2), buffalo manure (T3), N:P:K (25:25:0) (T4) and control pond (T5) have been determined for the period of one year. The overall biomass conversion efficiencies under the influence of T2, T3, and T4 were statistically similar. However, the best (0.40) efficiency was determined under feed supplement-ation (T1).

EPON 시스템에서 Bandwidth 효율을 높이기 위한 DBA 알고리즘 (DBA Algorithm for Improving Bandwidth Efficiency in EPON System)

  • 김규원;배경원;엄호석;정제명
    • 한국광학회:학술대회논문집
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    • 한국광학회 2005년도 제16회 정기총회 및 동계학술발표회
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    • pp.160-161
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    • 2005
  • A critical issue in implementing efficient Ethernet passive optical network(EPON) System is the bandwidth allocation algorithm. The overall goal of bandwidth allocation is to effectively and fairly perform scheduling of time slots between ONUs in EPON System. We propose a new algorithm of dynamic bandwidth allocation for improved bandwidth efficiency in EPON system.

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디젤기관 흡기다지관의 최적설계에 관한 기초연구 (A Study on the Optimum Design of the Intake Manifold for Diesel Engine)

  • 최성규;전효중;최재성;박태인
    • Journal of Advanced Marine Engineering and Technology
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    • 제14권4호
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    • pp.72-80
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    • 1990
  • In this paper, the gas dynamic effects of the suction pipe systems which have resinators are investigated on the volumetric efficiency are theoretically investigated by the engine performance simulation program which has been already developed. As the results, the optimum design method of the suction pipe system which has the overall high the flat characteristic curve of volumetric efficiency is developed in case of one cylinder engine.

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고효율, 저손실을 갖는 1단 교류/직류 변환기의 역률제어 (Power Factor Correction of the Single Stage AC/DC Converter with Low Conduction Loss and High Efficiency)

  • 류명효;차영길;최병조;김흥근
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 1998년도 전력전자학술대회 논문집
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    • pp.418-422
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    • 1998
  • A new single stage AC/DC converter based on the forward converter is proposed. The proposed converter offers both the high power factor and the direct conversion from ac line to dc output voltage. Also, the proposed converter reduces the diode conduction loss, so improves the overall efficiency of the converter, compared with other alternatives. The principles of operation and the simulation results of the proposed converter are presented. A 100 W prototype was built and tested to show the potential of applications of the proposed converter.

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Full-Color Phosphorescent OLEDs: Maximizing Performance Today for Small-Area Portable Products and Tomorrow for TVs

  • Brown, Julie J.;Adamovich, Vadim.I.;Ma, Bin;D’Andrade, Brian;Kwong, Raymond C.;Weaver, Michael S.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.427-430
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    • 2007
  • Phosphorescent OLED technology is a core technology driver for OLED display and lighting products due to the inherent and demonstrated efficiency advantages. Here we present recent results in our continued advancements of PHOLED power efficiency and operational stability with focus on narrowing emission line-width, reducing voltage, and overall design for maximizing device lifetime.

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The Intergenerational Effects of Tax Policy in an Overlapping Generations Model with Housing Assets

  • LEE, YOUNG WOOK
    • KDI Journal of Economic Policy
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    • 제40권2호
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    • pp.53-73
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    • 2018
  • Using an overlapping generations model, this paper examines tax policy effects across generations. The model incorporates housing assets separately from capital assets and includes taxes on labor income, capital income, consumption and housing assets. Tax reforms for each tax rate have different effects on tax burdens across generations and the overall efficiency of the economy, leading to different welfare costs for generations. Specifically, raising housing property taxes results in the smallest welfare loss by future generations, as in the model it does not hurt economic efficiency and the tax burden increases mainly for the elderly, who have accumulated housing assets in preparation for retirement.

Simulation and Experimentals of a Bi-Directional Converter with Input PFC on SRM System

  • Maged Maged N.F.
    • Journal of Power Electronics
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    • 제6권2호
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    • pp.121-130
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    • 2006
  • This paper presents the performance and efficiency of a drive system incorporating a switched-reluctance motor (SRM) with input power factor correction (PFC). The proposed system consists of a PFC, bi-directional converter, an inverter, and a SRM operating as based voltage source drives (VSD). First, theoretical analysis is made for each identified mode of operation in the drive system. This is followed by comparing the performance of the SRM drive system with and without a PFC circuit. The losses are also calculated for both systems and overall efficiency. Experimental results are presented to prove the theoretical analysis.

공공병원의 효율성 및 생산성 분석 (Measuring Efficiency and Productivity of the Korean Public Hospitals)

  • 유태우;임종은;지홍민
    • 한국경영과학회지
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    • 제29권3호
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    • pp.79-98
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    • 2004
  • Despite its contribution to the Korean medical service industry the question of how efficiently the Korean public hospitals have operated has been unresolved. This study gauges and analyzes the overall efficiency and the Malmquist productivity index in the industry over the period 1992 through 2001. In addition to cost efficiency. we also measure technical, allocative, pure technical and scale efficiencies. Furthermore. the Malmquist index is decomposed into efficiency and frontier changes. We identify several important factors which seem to have strong relationship with various inefficiency estimates. The results indicate that on average the public hospitals has wasted a significant amount of resources and costs over the period. Unlike many other industries, the low level of cost efficiency of the public hospital industry is mainly due to allocative inefficiency rather than technical inefficiency. The Maimquist productivity indices seem both due to the frontier change and efficiency change, but with more effect by the former. The results also indicate that the turnover of hospital beds has played an important role in determining efficiency and productivity of this important industry.

GaN FET를 적용한 인터리브 CRM PFC의 효율특성에 관한 연구 (A Study on the Efficiency Characteristics of the Interleaved CRM PFC using GaN FET)

  • 안태영;장진행;길용만
    • 전력전자학회논문지
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    • 제20권1호
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    • pp.65-71
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    • 2015
  • This paper presents the efficiency analysis of a critical current mode interleaved PFC rectifier, in which each of three different semiconductor switches is employed as the active switch. The Si FET, SiC FET, and GaN FET are consecutively used with the prototype PFC rectifier, and the efficiency of the PFC rectifier with each different semiconductor switch is analyzed. An equivalent circuit model of the PFC rectifier, which incorporates all the internal losses of the PFC rectifier, is developed. The rms values of the current waveforms main circuit components are calculated. By adapting the rms current waveforms to the equivalent model, all the losses are broken down and individually analyzed to assess the conduction loss, switching loss, and magnetic loss in the PFC rectifier. This study revealed that the GaN FET offers the highest overall efficiency with the least loss among the three switching devices. The GaN FET yields 96% efficiency at 90 V input and 97.6% efficiency at 240 V, under full load condition. This paper also confirmed that the efficiency of the three switching devices largely depends on the turn-on resistance and parasitic capacitance of the respective switching devices.

한국의 통관서비스 효율성 분석에 관한 연구 (Efficiency Analysis on Customs Clearance Service of Korea)

  • 이기웅
    • 무역상무연구
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    • 제53권
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    • pp.315-336
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    • 2012
  • In year 2011 export volume of South Korea surpassed 500billion USD and overall trade volume has exceeded one trillion USD. South Korea is ranked at 7th in the world by its export volume. Such an expansion of the trade volume leads to growth in customs clearance service demand. However, there are only handfuls of studies on the efficiency of customs clearance service which customs broker provide. If the efficiency in this study is not absolute, it shows relative efficiency to decision making unit. In this research survey was conducted targeting members of Korea Customs Brokers Association. Based on the survey improvement plans to enhance efficiency of customs clearances are as follows. First, rationalize the customs broker fee. Second, setup batch processing system to improve efficiency of the work process. Third, develop new area of task such as FTA and AEO certification. Forth, raise service quality by improving professionalism of customs brokers. Fifth, work efficiency of the office in the capital area will increase. Sixth, when inspecting import export cargo, customs broker should attend at the scene by their choice. Meanwhile, difference analysis on competent customs, type of office, and duration of the business was done but all the aspects were rejected. Such aspects does not influence on its effectiveness.

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