• 제목/요약/키워드: current standard

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Development of an automatic measurement system for the AC-DC current transfer difference of the thermal current converter (열전형 전류 변환기의 교류-직류 전류 변환차이 자동측정시스템 개발)

  • Kwon, Sung-Won;Jung, Jae-Kap;Kim, Mun-Seog;Kim, Kye-Tae;Ryu, Je-Cheon
    • Journal of Sensor Science and Technology
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    • v.14 no.5
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    • pp.350-356
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    • 2005
  • We have developed a dual-channel type automatic measurement system to evaluate AC-DC current transfer difference of the thermal current converter(TCC) which is primary standard of AC current. The output drift effect of the TCC is minimized by measuring simultaneously the output voltages of two TCCs using voltmeter. Furthermore, the offset voltage of the voltmeter is cancelled nearly out by taking the average values of two outputs of TCCs measured with the forward-reverse directions using dual channel scanner. The uncertainties of the automatic system were 7 to $86{\mu}A/A$ for 3 mA to 10 A at 40 Hz to 20 kHz, which were evaluated by the comparisons between adjacent range of TCCs and inter-comparison with national measurement institute of Germany(PTB). The capability for ac-dc transfer difference measurement was improved by one order compared with that for the manual ac-dc measurement system.

A Study on the Efficient Improvement of Standard Apartment Management Rules (공동주택관리규약(共同住宅管理規約)의 개선방안(改善方案) 연구(硏究))

  • Yoon Hyung-In;Ahn Hyo-Soo
    • Journal of the Korea Institute of Building Construction
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    • v.6 no.3 s.21
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    • pp.83-90
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    • 2006
  • The purpose of this study is to propose improved apartment management rules so that the inhabitants of apartment houses can manage their apartment in efficient and transparent manners. This study points out several problems of current management system and propose improved apartment management rules by analyzing misconducts of management office, related laws and regulations, standard apartment management rules, these and judicial decisions. Therefore, the inhabitants may refer to this study in establishment or amendment of their apartment management rules.

A Study on the Effect and Improvement Directions of KGBCC based on the Comparison of Green Residents Satisfaction (친환경 주거단지의 거주자 만족도 비교를 통한 친환경 건축물 인증제도 효과 및 개선방향 연구)

  • Kwon, Hyuk-Jin;Yeom, Dong-Woo;Lee, Kyu-In
    • KIEAE Journal
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    • v.11 no.5
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    • pp.79-90
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    • 2011
  • The KGBCC(Korean Green Building Certification Criteria), which is the assessment standard of green buildings, is not enough to reflect all the current demands of residents. Therefore, the comparative analysis between the certification score and the residents' satisfaction of a promotional green apartment, a awarded green apartment, and a certified green building apartment was carried out to derive improvements of the KGBCC. The residents of selected three apartments were surveyed through the assessment items of the KGBCC. According to the research, the certified green building apartment shows the highest certification score and residents' satisfaction overall, compared with other two apartments. Finally, the improvements of KGBCC were determined through the reason of the residents' dissatisfaction. The KGBCC that is improved by this study can be used for the new assessment standard of green buildings.

A Study on QoS-aware Wirelss LAN Protocols Adapting Channel Condition Variations (채널 특성 변화에 적응하며 QoS 보장이 가능한 무선 랜 프로토콜 연구)

  • Lee, Kye-Sang
    • Proceedings of the IEEK Conference
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    • 2005.11a
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    • pp.245-248
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    • 2005
  • Wireless LANs based on the IEEE 802.11 standard are widely spread for use nowadays. Traffic which are conveyed over the WLANs change rapidly from normal data such as Email and Web pages, to multimedia data of high resolution video and voice. To meet QoS (Quality of Service) required by these multimedia traffic, the IEEE 802 committee recently has developed a new standard, IEEE 802.11e. Current IEEE 802.11e, however, is not sufficient to support service differentiations and network performance enhancements, under a varying network environment experiencing as varying channel characteristics and high network loads. Recently, there have been much research to complement this deficiency of 802.11e standard. This paper surveys these research efforts.

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Domestic Technical Standards and Performance Test of Photovoltaic PCS for Renewable Energy (신재생에너지용 태양광 PCS 국내 기술기준 및 성능시험)

  • Yoon, Yong-Ho
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.67 no.3
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    • pp.479-484
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    • 2018
  • This paper describes domestic technical standard of Photovoltaic(PV) PCS(Power Conditioning Systems)-Characteristics of the utility interface. This standard tests utility compatibility and personnel safety and equipment protection of PV inverter performance functions. Especially utility compatibility part includes test items of 1)voltage, current and frequency, 2)normal voltage operating range, 3)DC injection, 4)normal frequency operating range, 5)harmonics and 6)waveform distortion, 7)power factor of PV inverter. Therefore in this paper each test item of domestic technical standard is studied and analyzed and finally full tested by PV inverter performance function.

Command and Telemetry System Design for Low earth orbiting satellite considering the PUS concept (PUS 개념을 이용한 차세대 저궤도위성의 원격명령어 및 텔레메트리 시스템 개발)

  • Lee, Na-Young;Lee, Jin-Ho;Suk, Byong-Suk
    • Aerospace Engineering and Technology
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    • v.6 no.1
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    • pp.92-96
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    • 2007
  • The conventional commands & telemetry system of Korean low-earth orbiting satellites has certain limitations in accommodating various missions. As the payload becomes complex, it requires very complicated operational concepts in terms of commands and telemetry. With the current design, commands and telemetry formats have to be rebuilt whenever new payloads or operation concepts are involved, and many constraints in operation shall be produced due to the lacks of its flexibility. In this paper, a new strategy for commands & telemetry development partially derived from PUS (Packet Utilization Standard) of European Space Agency, which provides enhanced features for the accommodation of payloads & operational requirements, is presented.

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A Study of the Job Analysis for Library Children's Services in Korea (도서관 아동서비스를 위한 직무분석 연구)

  • Yoon, Hee-Yoon
    • Journal of the Korean Society for Library and Information Science
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    • v.42 no.2
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    • pp.5-27
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    • 2008
  • The purpose of this paper based on the preliminary research is to dove)or the standard job models for children's service of public and children libraries in Korea. To do so, the author surveyed and analysed the perception of library staff of current jobs for children's service using the online questionnaire. And author proposed the standard models(importance difficulty, professionalism, and performance requirements) of library jobs for strengthening children's services. In addition, the this study suggested a plans to enhance professionalism of children's librarian and to introduce its qualification system.

An Application-Level Fault Tolerant System For Synchronous Parallel Computation (동기 병렬연산을 위한 응용수준의 결함 내성 연산시스템)

  • Park, Pil-Seong
    • Journal of Internet Computing and Services
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    • v.9 no.5
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    • pp.185-193
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    • 2008
  • An MTBF(mean time between failures) of large scale parallel systems is known to be only an order of several hours, and large computations sometimes result in a waste of huge amount of CPU time, However. the MPI(Message Passing Interface), a de facto standard for message passing parallel programming, suggests no possibility to handle such a problem. In this paper, we propose an application-level fault tolerant computation system, purely on the basis of the current MPI standard without using any non-standard fault tolerant MPI library, that can be used for general scientific synchronous parallel computation.

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Users Participation in IMT-2000 Standardization upon Phased Standards Strategy

  • Myung, Jong-Wook
    • Proceedings of the Korea Technology Innovation Society Conference
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    • 1998.05a
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    • pp.22-22
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    • 1998
  • This paper reviews the benefits of users participation in IMT-2000 standardization by the creation of users coalitions, focusing in particular on phased standards strategy necessary for the evolutionary approach from second generation to third generation systems. It first presents in detail the current status of IMT-2000 standardization progress occurring at each regional standard body including TIA of US, ETSI of Europe, TTA of Korea and ARIB of Japan. With this clear understanding of standardization situations worldwide, we may be able to come up with our standards strategies related to IPR issues and efficient standard-setting mechanism between manufacturers and service providers. In addition, this paper addresses the necessity for phased licensing of IMT-2000 service in order to avoid the high cost of new infrastructures and ensure an acceptable financial investment returns for existing cellular and PCS service providers. An author hopes that this paper can provide the adequate standardization directions of IMT-2000 to satisfy the varying regional and global market requirements.

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A 3.3-V Low-Power Compact Driver for Multi-Standard Physical Layer

  • Park, Joon-Young;Lee, Jin-Hee;Jeong, Deog-Kyoon
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.7 no.1
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    • pp.36-42
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    • 2007
  • A low-power compact driver for multistandard physical layer is presented. The proposed driver achieves low power and small area through the voltage-mode driver with trans-impedance configuration and the novel hybrid driver,. In the voltage-mode driver, a trans-impedance configuration alleviates the problem of limited common-mode range of error amplifiers and the area and power overhead due to pre-amplifier. For a standard with extended output swing, only current sources are added in parallel with the voltage-mode driver, which is named a 'hybrid driver'. The hybrid architecture not only increases output swing but reduces overall driver area. The overall driver occupies $0.14mm^2$. Power consumptions under 3.3-V supply are 24.5 mW for the voltage-mode driver and 44.5 mW for the hybrid driver.