• Title/Summary/Keyword: Independent Park

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Linear Relationships Between Thermodynamic Parameters Part IV Studies on Basicities of Some Substituted Dimethylanilines (熱力學函數間의 直線關係 第四報 Dimethylaniline 直換體의 鑒基度에 關한 硏究)

  • Lee, Ik-Choon;Park, Yong-Ja
    • Journal of the Korean Chemical Society
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    • v.8 no.1
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    • pp.15-19
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    • 1964
  • Basicities of nine dimethylanilines have been determined in 50, 70, and 90 volume % ethanol, at $25^{\circ},\;30^{\circ},\;35^{\circ},\;and\;40^{\circ}C$. Temperature coefficients were found to be independent of solvent composition, while they showed a linear correlation with basicities of the compounds. Thermodynamic parameters obtained have been used in the discussion of substituent and solvent effects in conjunction with the general equation derived in the preceding papers.

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Performance Evaluation of an XML-Based Conference Control Protocol for Centralized VoIP Conference

  • Kim, Eun-Sook;Yi, Jong-Hwa;Kang, Shin-Gak;Park, Ki-Shik
    • ETRI Journal
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    • v.26 no.2
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    • pp.181-184
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    • 2004
  • For communication between heterogeneous conference systems, it is important to build a conference control protocol independent from signaling protocols. We simulate an XML-based conference control that is under consideration as a standard mechanism. We describe the framework and operations for easy implementation in heterogeneous conference systems. The simulation results show that the proposed control protocol provides a consistent service for an increasing number of conferences and participants in small to mid-size centralized conferencing.

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An Analysis on the Characteristics on Incubator Organization Ventures and Independent Ventures (배태조직 벤처기업과 개인창업 벤처기업의 특성분석)

  • Kim, S.K.;Park, B.S.;Oh, K.S.
    • Electronics and Telecommunications Trends
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    • v.17 no.6 s.78
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    • pp.127-134
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    • 2002
  • 정보통신 연구개발 사업인 우수신기술 지정 ·지원사업에 참여한 벤처기업 중 초기단계 벤처기업 75개사를 대상으로 대기업 및 중소기업으로부터 spin-off한 배태조직 벤처기업과 개인창업 벤처기업으로 분류하여 업종 및 벤처확인 유형별 특성, 재무 및 조직현황 특성, 최고경영자 특성, 기술개발 특성, 해외진출 특성을 분석하여 두 그룹간의 차이점 및 공통점을 파악한 후 향후 벤처기업의 나아갈 방향에 대해 제시해 보았다.

DRAM bus system을 위한 analog calibration 적용 Pre-emphasis Transmitter

  • Park, Jeong-Jun;Cha, Su-Ho;Yu, Chang-Sik;Gi, Jung-Sik
    • Proceedings of the IEEK Conference
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    • 2006.06a
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    • pp.653-654
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    • 2006
  • A Pre-emphasis transmitter for DRAM bus system has achieved 3.2Gbps/pin operation at 1.8V supply voltage with 0.18um CMOS process. The transmitter has 800MHz PLL to generate 4 phase clocks. The 4 phase clocks are used for input clock of PRBS and multiplexing. One tap pre-emphasis is used to reduce inter symbol interference (ISI) caused by channel low pass effects. The analog calibration makes the optimized driver impedance independent with the PVT variation.

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Closest Open Location Rule in AS/RS

  • Park, Byung-Chun
    • Journal of Korean Institute of Industrial Engineers
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    • v.13 no.2
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    • pp.87-95
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    • 1987
  • This article deals with the expected travel distances under Closest Open Location rule. In this paper it is shown that uniform distribution assumption over a rack, which is usually used when modeling randomized storage, is not valid under COL rule, where arrival loads follow Poisson process and duration times are independent of each other and have finite mean. We give both exact and approximate methods for the expected travel distances. Warehouse sizing problem is also included.

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THE MINIMUM VARIANCE UNBIASED ESTIMATION OF SYSTEM RELIABILITY

  • Park, C.J.;Kim, Jae-Joo
    • Journal of Korean Institute of Industrial Engineers
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    • v.4 no.1
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    • pp.29-32
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    • 1978
  • We obtain the minimum variance unbiased estimate of system reliability when a system consists of n components whose life times are assumed to be independent and identically distributed either negative exponential or geometric random variables. For the case of a negative exponential life time, we obtain the minimum variance unbiased estimate of the probability density function of the i-th order statistic.

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PFC Controller Design for 3-Phase Modular UPS (3상 모듈형 UPS용 PFC 제어기 설계)

  • Park, Nae Chun;Kim, Sang Hoon;Ji, Jun Keun
    • Proceedings of the KIPE Conference
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    • 2010.11a
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    • pp.44-45
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    • 2010
  • In this paper a new PFC Controller for 3-Phase Modular UPS is proposed. The PFC circuit for 3-Phase Modular UPS is implemented using three 1-phase 3-level boost PFC circuits. To control DC output voltage and AC input current, single voltage controller considering imbalance of two capacitor voltages and three independent current controllers are used in proposed PFC controller.

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An Exploratory Study on the Meaning of Visual Scaffolding in Teaching and Learning Contexts

  • PARK, Soyoung
    • Educational Technology International
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    • v.18 no.2
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    • pp.215-247
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    • 2017
  • This study aims to conduct a literature review on visual scaffolding. Visual scaffolding, as a support for learning, employs various forms of visual objects which can be either content-independent or content-dependent and the types of which would be abstract-verbal, concrete-verbal, concrete-visual, or abstract visual. The effectiveness of visual scaffolding can be argued in the following three aspects: 1) explicit representation of information and emphasis of critical features in effective and efficient manner, 2) supplement of additional information, 3) structural understanding with decrease in cognitive load. The limitations of the study and the suggestions for future study are discussed.