• Title/Summary/Keyword: PCS

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A study on teletraffic analysis in overlaid PCS system (다중계위 셀 구성을 갖는 PCS망의 트래픽 분석)

  • 김영일;진용옥
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.21 no.2
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    • pp.394-408
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    • 1996
  • In this paper, we classify the transfer method of overflowed traffic from microcell to macrocell in micor/macro overlaid PCS system using CDMA technology, and analyze the traffic characteristics of traffic transfer methods. Soft-handoff is charaterized by communications with a new bastation on the same CDMA frequency assignment before terminating communications with the old basestation. Therefore, soft-handoff is superior to hard-handoff with respect to Grade Of Service, but it decreases the carried traffic of system. Therefore, we analyze the effect of soft-handoff with respect to handoff area variation. In order to analyze soft-handoff effect, we resolve the probability of dewelling time in soft-handoff area, and calculates the carried traffic of microcell using this result.

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A Study of Non-Detection Zone using AFD Method applied to Grid-Connected Photovoltaic Inverter for a variety of Loads (계통연계형 태양광발전 인버터에 사용된 AFD기법의 다양한 부하에 따른 단독운전 불검출영역에 대한 고찰)

  • Ko, Moon-Ju;Choy, Ick;Choi, Ju-Yeop
    • Journal of the Korean Solar Energy Society
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    • v.26 no.1
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    • pp.91-98
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    • 2006
  • Islanding phenomenon of utility-connected photovoltaic power conditioning systems(PV PCS) can cause a variety of problems and must be prevented. If the real and reactive power supplied by PV PCS are closely matched to those of load, islanding detection by passive methods becomes difficult. The active frequency drift(AFD) method, called the frequency bias method, enables islanding detection by forcing the frequency of the voltage in the islanding to drift up or down. In this paper, non-detection zone(NDZ) of AFD is analyzed for the islanding detection method of utility-connected PV PCS by the simulation software tool PSIM.

PCS Design for Single power stage structured PV PCS using Z-source Inverter (Z-소스 인버터를 이용한 일단구조의 계통연계형 태양광 발전용 PCS 설계)

  • Shin, Hyun-Jin;Park, Joung-Hyoung;Kim, Heung-Geun;Chun, Tae-Won;Nho, Eui-Cheol
    • Proceedings of the KIPE Conference
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    • 2008.06a
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    • pp.314-316
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    • 2008
  • 계통연계형 태양광 PCS는 주로 전압원 인버터와 전압의 승압을 위한 DC/DC컨버터, 즉 이단구조로 구성된다. Z-소스 인버터는 DC/DC컨버터 없이 전압을 승/감압할 수 있다. 3k급 계통연계형 태양광 PCS에 Z-소스 인버터를 적용하여 일단구조로 설계하였고 PSIM 시뮬레이션과 실험을 통하여 타당성을 검증하였다.

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Dexmedetomidine intravenous sedation using a patient-controlled sedation infusion pump: a case report

  • Chi, Seong In;Kim, Hyun Jeong;Seo, Kwang-Suk
    • Journal of Dental Anesthesia and Pain Medicine
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    • v.16 no.1
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    • pp.55-59
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    • 2016
  • Dental treatment under sedation requires various sedation depths depending on the invasiveness of the procedure and patient drug sensitivity. Inappropriate sedation depth may cause patient discomfort or endangerment. For these reasons, patient-controlled sedation (PCS) pumps are commonly used. Patients are able to control the sedation depths themselves by pushing the demand button after the practitioner sets up the bolus dose and lock-out time. Dexmedetomidine is an ${\alpha}$-2 adrenoreceptor agonist with sedative, analgesic, and anxiolytic properties. It has been widely used for sedation for its minimal respiratory depression; however, there are few studies on PCS using dexmedetomidine. This study assessed the applicability of dexmedetomidine to PCS.

Patient-Controlled Sedation for Dental Treatment (치과치료를 위한 진정자가조절법)

  • Seo, Kwang-Suk
    • Journal of The Korean Dental Society of Anesthesiology
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    • v.13 no.3
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    • pp.81-87
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    • 2013
  • This article discusses the issues of benefit and possibility of application of patient-controlled sedation (PCS) for the dental treatment. The purpose of administering PCS for patients is to diminish anxiety and to provide cooperative and effective dental treatment. But there are a lot of barriers to application of PCS such as knowledge about pharmacokinetics of sedatives, expensive high speed and patient-controllable syringe pump, and well educated sedationist. And there could be risk of deep sedation, airway obstruction and hypoxic brain damages, etc. In order to decrease incidence of complication, appropriate drug selection, selection of right bolus dose, lock-out time is much important.

A Study on the Development of Dual-band PLL Frequency Synthesizer for miniature Repeater (초소형 중계기용 듀얼 밴드 주파수합성기 개발에 관한 연구)

  • 나영수;김진섭;강용철;변상기;나극환
    • Proceedings of the IEEK Conference
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    • 2003.11c
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    • pp.37-40
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    • 2003
  • The 1.63㎓, 2.33㎓ dual-band PLL frequency synthesizer has been developed for applications to the miniature repeater. The miniature dual-band repeater will be used at shopping mall, basements and underground parking lots. The in-loop 1.63㎓, 2.33㎓ dual-band PLL frequency synthesizer has been developed by designing Si BJT VCO and PLL loop circuits with Colpitts. The prototype of 1.63㎓, 2.33㎓ dual-band PLL frequency synthesizer of size 19${\times}$19${\times}$8(mm) has shown operating frequencies of 1.63㎓, 2.33㎓ ranges, RF output of 1dBm(PCS), 1dBm(IMT-2000), phase noise of -100 dBc/Hz(PCS), -95dBc/Hz(IMT-2000) at 10KHz offset, harmonics suppression of -24dB c(PCS), -15dBc(IMT-2000).

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Capacity Determination of ESS for Peak Load Shaving Based on the Actual Measurement of Loads in the Substation of Urban Railway (도시철도 실측 부하에 기반한 첨두부하 절감용 ESS 용량 산정)

  • Park, Jong-Young;Jung, Hosung;Kim, Hyungchul;Shin, Seungkwon
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.63 no.6
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    • pp.860-865
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    • 2014
  • This paper proposes the method for determination of the capacities of ESS (Energy Storage System) and PCS (Power Conditioning System) for the peak load shaving based on the load data in the substation of urban railway. In addition, this paper analyze the actual measurement of loads in the substation of urban railway. The load of a weekday in the substation of urban railway is high around rush hours in the morning and evening, which is different from that of a normal substation. The required capacities of ESS and PCS become larger as the amount of peak load shaving is higher, and are affected from the patterns of daily load in the substation.

DC Common Method of Hybrid PCS Overseas Demonstration Operation (DC Common 방식 Hybrid PCS 해외 실증 운전)

  • Hong, Seokyong;Yang, Daeki;Yu, Seungyeong;Jung, Sehyung;Kim, Minkook;oh, Seongjin;Choi, Sewan
    • Proceedings of the KIPE Conference
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    • 2018.07a
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    • pp.348-349
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    • 2018
  • 본 논문은 DC Common 방식의 Hybrid PCS (Power Conditioning System)의 해외 실증사례에 대해 서술하고 있다. 본 시스템은 계통, PV(Photovoltaic), BESS (Battery Energy Storage System)로 구성되어 있으며 UAE의 Dubai에 60kW급 2기, 200kW급 1기를 실증한 사례를 설명한다. 각 구성품 들의 사양과 Destin Power사 Hybrid PCS를 소개하고 사양을 서술하였으며 실제 운영을 통하여 제품의 신뢰성을 검증하였다.

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The PCS system having the BESS function (BESS기능을 겸비한 PCS시스템 구성)

  • Kim, Sun-pil;Hwang, Jung-goo;Park, Sung-jun
    • Proceedings of the KIPE Conference
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    • 2013.07a
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    • pp.34-35
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    • 2013
  • 최근 신재생 에너지원의 증가와 더불어 전력 산업 전반의 요구에 대해 에너지 저장시스템(ESS, Energy Storage System)에 대한 필요성이 높아지고 있다. 전력 수요의 급격한 증가는 전력계통의 교란이 증가하게 되어 전력품질의 문제를 야기 시키고, 이에 따라 송배전 설비의 증설에 교구 커지고 있는 상황이다. 이에 대한 적절한 대안으로 배터리를 이용한 에너지 저장 시스템(BESS, Battery Energy Storage System)이 대두되고 있는 상황이며, 특히 계통연계형 PCS에 BESS를 적용시킬시에 능동적인 부하 평준화 기능을 통해 송배전 설비투자 지연의 목적을 달성할 수 있는 장점을 가진다. 따라서 본 논문에서는 BESS기능을 겸비한 PCS 시스템 구성을 제안하고, 이에 대하여 기술한다.

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Demand for Agricultural Information;Situation and Implication (농업정보이용 실태 및 과제)

  • Choe, Young-Chan
    • Journal of Agricultural Extension & Community Development
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    • v.3 no.2
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    • pp.177-195
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    • 1996
  • This study examines the demand for agricultural information at farm level, using Probit and Logit models. 646 farmers are surveyed with a questionnaire to attain the data and 441 of them have responded. The demand functions for computers, agricultural softwares, and agricultural databases at from level have been derived and used to project the demand for agricultural information in year $2001{\sim}2004$. Results find that only 5.89% of farmers have PCs at farm and rarely use the agricultural databases and softwares in 1994. The low demand figures are mostly due to the difficulty of using the PCs, databases, and softwares. The demand figures will increase in early 2000`s with 15.46% of farmers having PCs. User Friendly developed softwares and databases, and education for using agricultural information are necessary to increase the demand figures.

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