• 제목/요약/키워드: CES

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지역 에너지 시스템(CommunityEnergysystem)의 개통 연계 운전 특성 (An Impact Analysis of Community Energy System (CES) on The Grid)

  • 박용업;김황호;장성일
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 A
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    • pp.120-122
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    • 2004
  • This paper analyse impacts of Community Energy System (CES) on the grid during transition periods for integrating of the CES and the grid. In the near future, CES might be one of major energy supply structures. The basic concept of CES is that it supplies electrical and thermal energy to the local customer loads through the islanded power network separated from the grid. Therefore, the interconnection with the grid occurs only when the energy supply from the CES generators does not meet the demand of the local load. For avoiding impacting the grid during the transition operation modes of CES, it is necessary to thoroughly analyse the influences on the grid during those periods. In order to show them, in this paper, we model the CES with 2.34 WVA DG and simulate the impacts on the grid due to interconnection of CES The simulation results show that, in order to reduce bad influences of CES on the grid, CES need the efficient load management and generation control schemes during the transition periods.

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배합사료를 혼합한 옥수수-계분 silage의 품질과 사료가치 (Quality and Feed Value of Ensiled Whole Crop Corn with Cage Layer Excreta and Concentrate)

  • 고영두;김두환;김재황;강한석;박재학
    • 한국초지조사료학회지
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    • 제10권3호
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    • pp.164-171
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    • 1990
  • This study was carried out to enhance the nutritional value of whole crop corn silage and the utilization of animal waste as a ruminant feedstuffs. Whole crop corn were ensiled with cage layer excreta and concentrate. Treatments included whole crop corn silage (control), 10% cage layer excreta and concentrate-corn silage (CES lo), 20% cage layer excreta and 10% concentrate-corn silage (CES 20) and 30% cage layer excreta and 10% concentrate-corn silage (CES 30). The characteristics of silage fermentation was evaluated. Digestibility and palatability of the silage were observed through the feeding trial with four male Corridale sheep. The results obtained are summarized as follows: 1. Cage layer excreta-corn silage showed higher contents of crude protein and crude ash than control silage, while crude fibre content was significantlv lower than that of control silage (P(.01). 2. Total nitrogen and ammonia nitrogen content of the cage layer excreta-corn silage was significantly (P< .01) higher than that of control, but CES 10 silage was good in quality. 3. Lactic acid content of CES 10 silage was the highest, but that of CES 20 and CES 30 silage was lower than that of control. CES 20 and CES 30 silage was lower lactic acid content and higher pH than control. Therefore Flieg's score was wrose than that of control silage. 4. The numbers of total bacteria and lactic fermentation bacteria were estimated lo7-10' and 10"1OH, respectively, and there were no significant differences among treatments. Coliform numbers were not detected with CES 10 silage while were detected lo3 per gram in CES 30 silage. 5. Digestibility of crude protein, crude fibre and ADF was improved significantly in the animals fed the cage layer excreta-corn silage compared with animals fed the control silage. DCP and TDN were the highest in the CES 10 silage. 6. The intake of daily nitrogen and dry matter per metabolic body weight was the highest in animals fed the CES 10 silage.lage.

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커뮤니티에너지공급(CES) 시설 기반 마이크로그리드 기술

  • 박완기;최창식;한진수
    • 정보와 통신
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    • 제34권5호
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    • pp.61-67
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    • 2017
  • CES(Community Energy System) 마이크로그리드 기술은 에너지 생산/공급 및 소비가 일정 지역에 구역화하여 공급하는 집단에너지사업 중 구역전기사업이 이루어지는 커뮤니티에너지공급(CES) 시설 환경을 기반으로 이루어지는 마이크로그리드 시스템 기술이다. 마이크로그리드 환경을 위하여 CES 시설 환경을 기반으로 신재생발전, ESS 등 분산자원을 추가하고, 내부 전력시스템 개선 및 신규 에너지 서비스 인프라가 추가로 구축된다. 아울러, 이를 기반으로 마이크로그리드 환경에서 제공될 수 있는 에너지 서비스를 제공한다. 본고에서는 이러한 CES 마이크로그리드 기술에 대해 기술하고 최근 이루어지고 있는 CES 마이크로그리드 기술 개발의 사례를 통해 새로운 비즈니스 모델을 찾아보고자 한다.

지역 에너지 시스템의 계통 연계 및 독립 운전 특성에 관한 연구 (The Operating characteristics of Community Energy System(CES) with Grid connection and isolation)

  • 박용업;김광호;장성일
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 추계학술대회 논문집 전력기술부문
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    • pp.258-260
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    • 2004
  • This paper analyse a operating characteristics when the Community Energy System (CES) is operated islanding mode. In the near future, CES might be one of major energy supply structures. The basic concept of CES is that it supplies electrical and thermal energy to the local customer loads through the islanded power network separated from the grid. The CES must be supplying local load with stable energy on the islanding mode, analysing necessary to thoroughly the operation feature. In order to show them, in this paper, we model the CES with 2.34 MVA DG and simulate the operating feature on the islanding mode of CES. The simulation results show that, in order to stability operate, the CES need the efficient load management and generation control schemes during the transition periods.

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Effect of 1-aminocyclopropane-1-carboxylic acid (ACC)-induced ethylene on cellulose synthase A (CesA) genes in flax (Linum usitatissimum L. 'Nike') seedlings

  • Lim, Hansol;Paek, Seung-Ho;Oh, Seung-Eun
    • Genes and Genomics
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    • 제40권11호
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    • pp.1237-1248
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    • 2018
  • Introduction Cellulose microfibril is a major cell wall polymer that plays an important role in the growth and development of plants. The gene cellulose synthase A (CesA), encoding cellulose synthases, is involved in the synthesis of cellulose microfibrils. However, the regulatory mechanism of CesA gene expression is not well understood, especially during the early developmental stages. Objective To identify factor(s) that regulate the expression of CesA genes and ultimately control seedling growth and development. Methods The presence of cis-elements in the promoter region of the eight CesA genes identified in flax (Linum usitatissimum L. 'Nike') seedlings was verified, and three kinds of ethylene-responsive cis-elements were identified in the promoters. Therefore, the effect of ethylene on the expression of four selected CesA genes classified into Clades 1 and 6 after treatment with $10^{-4}$ and $10^{-3}M$ 1-aminocyclopropane-1-carboxylic acid (ACC) was examined in the hypocotyl of 4-6-day-old flax seedlings. Results ACC-induced ethylene either up- or down-regulated the expression of the CesA genes depending on the clade to which these genes belonged, age of seedlings, part of the hypocotyl, and concentration of ACC. Conclusion Ethylene might be one of the factors regulating the expression of CesA genes in flax seedlings.

토양내 K-CES와 PAM처리가 시금치의 생육에 미치는 영향 (Effects of Potassium-Cyanoethylstarch (K-CES) and Polyacrylamide (PAM) on Growth of Spinach (Spinacia oleracea L.))

  • 김석균;카와베타 사네유키;사키야마 료조
    • 원예과학기술지
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    • 제16권2호
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    • pp.226-228
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    • 1998
  • 타피오카 전분을 이용하여 제조한 흡수성 고분자 K-CES (potassium-cyanoethylstarch)와 합성계 고분자인 PAM (polyacrylamide) 처리가 시금치의 생육에 미치는 영향을 조사하였다. 타피오카 전분에 아크릴로니트릴을 반응시켜 시아노에틸화 전분을 제조하고, FT-IR 분석으로 니트릴기의 도입을 확인하였다. 제조한 K-CES와 PAM의 증류수에 대한 흡수력은 PAM이 47.8배로 K-CES의 37.6배에 비하여 다소 높았으나, $HNO_3$, $H_3PO_4$, $K_2SO_4$ 1% 용액에서는 PAM의 흡수력이 매우 감소하여 전해질 용액의 농도가 높을수록 K-CES의 흡수력이 클 것으로 생각되었다. PAM과 K-CES처리에 의해 시금치 초기생육의 촉진과 수량이 증가되어 흡수성 고분자 처리가 작물의 증수에 매우 효과적이었다.

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에탄올의 수분함량에 따라 합성된 Condensed Ethyl Silicate의 물성에 관한 연구 (A Study on the Properties of Condensed Ethyl Silicate Synthesized according to Water Contents in Ethanol)

  • 노재성;홍성수;서신석
    • 공업화학
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    • 제7권1호
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    • pp.91-100
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    • 1996
  • 사염화실리콘에 에틸알콜의 수분함랑을 2.5, 5.0, 7.0wt.%로 달리하여 축중합된 에틸실리케이트(CES : condensed ethylsilicate)용액들을 합성하였다. 용액의 졸-겔 전이 거동 조사를 위하여 시간경과에 따른 용액의 부피, 밀도, $SiO_2$ 함량, 본성점도 및 수평균분자량변화를 측정하였으며, 용액의 고분자 형상을 본성점도와 수평균분자랑 관계로부터 간접적으로 알아보았다. 에틸알콜의 수분함량을 7.0wt.%로 하여 합성한 CES-3는 수분함량이 2.5wt.%, 5.0wt.%인 CES-1, CES-2와 다른 졸-겔 전이 거동을 보였으며, 복합산화물계 요업재료 제조시에 TEOS의 가수분해 속도를 조절하기위하여 부분가수분해 시킨 PHT(Partially Hydrolysed TEOS)와 유사한 거동을 보였다. Mark-Hawink가 제시한 $[{\eta}]=K\bar{Mn}^{{\alpha}}$식에 의한 CES 및 PHT의 고분자형상은, 지수 ${\alpha}$값이 0.53~0.84로 용액 모두 선상 혹은 사슬상 고분자로 나타났으며, 이상의 졸-겔 거동과 고분자형상에 대한 비교 실험 결과로부터 CES-3는 PHT와 매우 유사한 물성을 가지고 있어 복합산화물계 요업재료의 원료로 사용될수 있는 가능성이 높은것으로 나타났다.

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백서에서 두개전기자극에 의한 척수신경원 흥분성의 변화 (The Change of Spinal Neuron Excitability by Cranial Electrostimulation(CES) in Rats)

  • 정대인;이정우;김태열;김영일
    • 대한임상전기생리학회지
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    • 제2권3호
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    • pp.37-49
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    • 2004
  • The purpose of this study was to determine the effect of spinal motor neuron excitability by cranial electrostimulation(CES). The fifteen Sparague-Dawley adult male rats were assigned to the three groups; GroupI(control), GroupII(low rate CES), GroupIII(high rate CES). Spinal motor neuron excitability was measured to use a computerized H reflex. The results of this study was as follows; M latency, M amplitude and H latency were no significant difference in all groups on repeated measured ANOVA(p>.05) but low rate CES and high rate CES groups were lower than ether group in comparative measurement of H amplitude and Hmax/Mmax ratio(p<.05). These results lead to the conclusion that spinal neuron excitability was influenced by CES. These results suggest that CES had the capability to lower spinal motor neuron excitability used synaptic blockade in spinal segment.

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푸리에 급수에 대한 체사로 총합가능성의 고전적 결과에 관하여 (On the classical results of Cesàro summability for Fourier series)

  • 이정오
    • 한국수학사학회지
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    • 제30권1호
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    • pp.17-29
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    • 2017
  • This paper is concerned with the $Ces{\grave{a}}ro$ summability of Fourier series. Many authors have studied on the summability of Fourier series up to now. Also, G. H. Hardy and J. E. Littlewood [5], Gaylord M. Merriman [18], L. S. Bosanquet [1], Fu Traing Wang [24] and others had studied the $Ces{\grave{a}}ro$ summability of Fourier series until the first half of the 20th century. In the section 2, we reintroduce Ernesto $Ces{\grave{a}}ro^{\prime}s$ life and the meaning of mathematical history for $Ces{\grave{a}}ro^{\prime}s$ work. In the section 3, we investigate the classical results of summability for Fourier series from 1897 to the mid-twentieth century. In conclusion, we restate the important classical results of several theorems of $Ces{\grave{a}}ro$ summability for Fourier series. Also, we present the research minor lineage of $Ces{\grave{a}}ro$ summability for Fourier series.

폐쇄형 흡인술이 인공호흡기 환자의 산소포화도, 인공호흡기 관련 폐렴 및 흡인간호 효율성에 미치는 영향 (Effects of a Closed Endotracheal Suction System on Oxygen Saturation, Ventilator-Associated Pneumonia, and Nursing Efficacy)

  • 이은숙;김성효;김정숙
    • 대한간호학회지
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    • 제34권7호
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    • pp.1315-1325
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    • 2004
  • Purpose: The purpose of this study was to examine the effects of a closed endotracheal suction system(CES) on oxygen saturation, ventilator associated pneumonia(VAP), and nursing efficacy in mechanically ventilated patients. Method: This study was conducted in the intensive care unit of a University Hospital in Gwangju City. Data was collected from July to October, 2003. Seventy mechanically ventilated patients were randomly divided into two groups; 32 for CES and 38 for open endotracheal suction system(OES) protocol. Twenty one nurses were also involved to examine the nurses' attitude of usefulness about CES. Result: $SaO_2$ was significantly different between CES and OES. The incidence of VAP in CES was lower than that of OES. Nursing efficacy was related to time, cost, and usefulness of the suction system. Time of suctioning in CES was shorter than that of OES. CES also contributed significantly to lower the cost of treatment than OES. The usefulness score of CES increased after 6 months of use. Conclusion: CES prevented VAP, was cost effective, and a safe suctioning system. CES can be used with patients with sensitivity to hypoxygenation and with a high risk of VAP.