• Title/Summary/Keyword: Improve The Efficiency

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Improve of efficiency of Multi D.O.F spherical motor through the reduction of eddy current loss (다자유도 구형 구동 모터의 와전류 손실 저감을 통한 효율 향상 연구)

  • Hong, Kyung-Pyo;Lee, Won-Kook;Lee, Ho-Joon;Kang, Dong-Woo;Won, Sung-Hong;Lee, Ju
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.947-948
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    • 2011
  • Efficiency of Multi D.O.F spherical motor is one of the important performance indicators. So Through the reduction of eddy current loss on how to improve the efficiency were studied. Stator iron core's material with high permeability and resistivity of material using the eddy current loss was reduced. However, it was the disadvantages of production and economic. For these reasons, prevent eddy current loss of the iron core of multi D.O.F spherical motor as a viable alternative to motor using rotor with double-air gap.

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Effective structure of electron injection from ITO bottom cathode for inverted OLED

  • Chu, Ta-Ya;Chen, Szu-Yi;Chen, Jenn-Fang;Chen, Chin H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.972-974
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    • 2005
  • For display drivers employ typically a-Si n-channel field effect transistors, they require an inverted OLED structure with a cathode as the bottom contact. ITO is regarded as the bottom cathode and can be applied to large size AM-OLED and transparent inverted OLEDs. We report the effective structure to improve the efficiency of electron injection from ITO cathode to $Alq_3$. We report the effective structure to improve the efficiency of electron injection from ITO cathode to Alq3 and studied the current density-voltage characteristics of trilayer ($Alq_3-LiF-Al$), LiF and Mg inserted between ITO and $Alq_3$, respectively. We discovered that 1 nm Mg afforded the highest efficiency.

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Performance Improvement of a Micro Eco Cross-Flow Hydro Turbine

  • Kokubu, Kiyoshi;Kanemoto, Toshiaki;Son, Sung-Woo;Choi, Young-Do
    • Journal of Advanced Marine Engineering and Technology
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    • v.36 no.7
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    • pp.902-909
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    • 2012
  • This study is aimed to develop a new type of micro cross-flow hydro turbine which has very simple structure and relatively high efficiency. Micro eco cross-flow hydro turbine (ECFT) is proposed to apply in the ranges of very low and middle specific speeds in order to extend the operational range of the turbine. In order to not only obtain a basic data for a new design method of ECFT but also improve the turbine efficiency, experiments and CFD analysis on the performance and internal flow characteristics of the turbine model are conducted. According to the present study results, anti-recirculation block (ARB) and relatively wide turbine width with high flow rate improve the turbine efficiency.

Tutorial: Design and Optimization of Power Delivery Networks

  • Lee, Woojoo
    • IEIE Transactions on Smart Processing and Computing
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    • v.5 no.5
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    • pp.349-357
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    • 2016
  • The era of the Internet of Things (IoT) is upon us. In this era, minimizing power consumption becomes a primary concern for system-on-chip designers. While traditional power minimization and dynamic power management (DPM) techniques have been heavily explored to improve the power efficiency of devices inside very large-scale integration (VLSI) platforms, there is one critical factor that is often overlooked, which is the power conversion efficiency of a power delivery network (PDN). This paper is a tutorial that focuses on the power conversion efficiency of the PDN, and introduces novel methods to improve it. Circuit-, architecture-, and system-level approaches are presented to optimize PDN designs, while case studies for three different VSLI platforms validate the efficacy of the introduced approaches.

A Current-Mode DC-DC Buck Converter with PFM to Improve the Light-Load Efficiency (Light-load에서 고효율을 가지는 PFM 전류모드 DC-DC Buck 변환기)

  • Ahn, Young-Kook;Nam, Hyun-Seok;Roh, Jeong-Jin
    • Proceedings of the IEEK Conference
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    • 2008.06a
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    • pp.601-602
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    • 2008
  • This paper presents pulse-frequency modulation(PFM) to improve the light-load efficiency. The proposed circuit is designed by using the device parameter of standard $0.13{\mu}m$ CMOS process. The performance of proposed circuit is evaluated by HSPICE simulation Measured efficiency in a light-load is measured 78-90 % for 0.1 to 100mA output current.

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Adjustable Switching Angle Control Method for High Efficiency SRM Drive (SRM의 고효율구동을 위한 가변 스위칭각 조정방식)

  • Kim, Jeong-Hong;Kong, Gwan-Sik;Ahn, Jin-Woo;Hwang, Young-Moon
    • Proceedings of the KIEE Conference
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    • 1994.07a
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    • pp.9-11
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    • 1994
  • This paper describes an adjustable switching angle control method of Switched Reluctance Motor to improve the drive efficiency when variable loads applied. The control method to build-up optimal current shape is intended to improve the efficiency of SRM over the wide range of output power without requiring additional power devices, which gives more economic benefits compared with any other control methods.

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The Research on Performance of PCB type of Solar cell BusBar Formed by Layer Structure (적층구조로 형성된 PCB형 태양전지용 BusBar의 성능에 관한 연구)

  • Jeon, Taeg-Jong;Cho, Nam-Cheol;Lee, Chae-Moon
    • 한국태양에너지학회:학술대회논문집
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    • 2012.03a
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    • pp.102-107
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    • 2012
  • The purpose of thesis is to improve output of solar cell module by enhancing transmission efficiency. To improve transmission efficiency, transmission interconnection ribbon which is used to connect solar cells and busbar which contacts with it has been improved. To secure reliability, comparison research on output of solar cell modules has been conducted by manufacturing PCB module formed by laminated metal with the same output. The result of this research is based on a output efficiency test of modules by comparing electric conductivity of soldering busbar and laminated PCV type of busbar.

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Strategies for International Aviation to Respond to Climate Change (국제민간항공분야의 기후변화 대응 전략 연구)

  • Yoo, Kwang Eui
    • Journal of Climate Change Research
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    • v.9 no.4
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    • pp.313-318
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    • 2018
  • The growth rate of international aviation is expected to be higher than that of most industries and the proportion of carbon emissions from the aviation industry will become very significant as the year 2050 approaches. Constraining the growth of this industry is not desirable because it is essential for human welfare as well as the development of related industries. However, reduction of carbon due to aviation is not easy because it is difficult to improve fuel efficiency in a significant way. The ICAO (International Civil Aviation Organization), which is the main organization responsible for handling this problem, developed a program named CORSIA (Carbon Offsetting and Reduction Scheme for International Aviation). The present study analyzes various strategies for countries and airlines to comply with CORSIA using a fuel-efficient system. We conclude that countries should improve their airspace utilization systems, airport facilities, and air navigation systems. Additionally, based on the results of a flight data analysis, airlines should improve their operational efficiency in terms of operations control, flight operation, and maintenance management.

A Study on the Electronic Clearance System of the Advanced Countries and Korea (선진국과 한국의 전자통관제도에 관한 연구)

  • Eom, Kwang-Yeol;Song, Seon-Uk
    • International Commerce and Information Review
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    • v.5 no.2
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    • pp.185-204
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    • 2003
  • Electronic Clearance System in the Advanced Countries give sane hints Clearance System in Korea to improve. It is as follows. It is necessary to enhance the economical efficiency and rapidity on clearance system. It is important to improve the conveniency of importer and export through all day services in customs. It is necessary to control export and import goods efficiently for guarantee of security. Export entry data in export country has to linked with import entry data in import country to improve speedy, correctness, and efficiency. It is necessary to solve the security problems through the use of the latest cryptograph.

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XML Query-Expansion by Ontology-DTD Match (온톨로지-DTD 정합에 의한 XML 질의 확장)

  • Kim, Myung-Sook;Kong, Yong-Hae
    • The KIPS Transactions:PartD
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    • v.12D no.5 s.101
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    • pp.773-780
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    • 2005
  • If XML queries are expanded based on ontology, broader search may be possible. On the other hand, queries that are not adequate to target documents may also degrade the search efficiency. We try to improve query adequacy by expanding query based on a reduced ontology, which is the result of ontology and target DTD match. The match considers ontology concepts and DTD elements as well as ontology and DTD attributes. Since the reduced ontology can improve the hit ratio of queries and also be successively reusable for XML documents of a kind, the proposed method can improve XML search efficiency.