• Title, Summary, Keyword: Reserve

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A Study of Reserve Book System (지정도서제도에 관한 연구)

  • 고성수
    • Journal of Korean Library and Information Science Society
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    • v.4
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    • pp.1-38
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    • 1977
  • This paper intend to analyze, review and point out the actual conditions of "Reserve Book System" of university libraries in Korea, then to present several proposals. I took six national universities and six private universities as researching objects and the materials were collected by questionnaires. 1) There are so many libraries which have no seperate reserve books room, while every colleges, and their departments are putting into forces the reserve book system. This makes many unresonable problems. 2) Many volumes were not adequate to the courses of each depertment and so many problems arose to set up reserve books owing to Lhe lack of library budget. 3) Insincerities of professors and librarians make no good conditions for the reserve book system. 4) For insufficiency of understanding about the reserve book system cf professors and students with university authorities, we must persuade and guide them about this system. 5) We imust evaluate about the problems of the reserve book system. I show the methods which is necessary to solve the problems of this system in the following. 1) As to methods of improving the field of menagement for running about the reserve book system, a) Establishment of the independent reserve books room. b) Gradual expansion of the reserve book system. c) Evaluation of the actual using of reserve books. 2) As to contents to improve the reserve book system, a) Improving the selection method of reserve books. b) Increasing the library budget enable to purchase more reserve books. c) Making more close connections between the curricula ard reserve books. 3) Settlment of coordinating system for carrying out reserve book system, a) We must have mutual understanding and co-operation among university authorities, faculties and libraries. b) We must have co-operation between professors and librariars.ibrariars.

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Determination of Secondary Reserve Requirement Through Interaction-dependent Clearance Between Ex-ante and Ex-post

  • Kim, Sun Kyo;Park, Joon-Hyung;Yoon, Yong Tae
    • Journal of Electrical Engineering and Technology
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    • v.9 no.1
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    • pp.71-79
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    • 2014
  • This paper discusses a method for the determination of frequency control reserve requirement with consideration of the interaction between ex-ante planning and real-time balancing. In proposed method, we consider the fact that the delivered energy for tertiary control reserve is determined based on required capacity for secondary control reserve and the expected amount of load errors. Uncertain load errors are derived by Brownian motion, an optimization method is suggested using a stochastic programming. In a short, we propose an interactive dependent method for determining secondary control reserve requirement based on the principle that it satisfies to minimize the total cost. As a result, this paper provides will analyze for an example model to demonstrate the capabilities of the method.

Nature Protection and Nature Reserve Policy in China (중국의 자연보존사업과 자연보호정책의 변화)

  • Jin, Yong-Huan
    • Proceedings of the Korean Society of Environment and Ecology Conference
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    • pp.7-20
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    • 2009
  • On the basis of introducing the development process of Chinese nature reserve since first nature reserve was set up in 1959 in China, and comparing the definition of nature reserve between IUCN and China, combining with the objectives and significance of the establishment of Chinese Nature Reserve, the present state and achievements of nature reserve in China were introduced detailedly. And the effect of the laws and rules on the protection in nature and biodiversity was assessed after analyzing the characteristics of the interrelated laws and rules enacted in course of development of Chinese nature reserve over 50 years. Also the qualifications and procedures of nature reserve establishment and relevance aspects of content in China were narrated, and the classification system and management system of Chinese nature reserve and their characteristics were introduced. Finally, the Medium and Long Term Program for Nature Reserve Development in China was introduced, and present some proposals to solve the problems on the basics that discuss the distribution status and its characteristics and problems on managing nature reserve in China.

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A Research of Optimum Supply Reserve Levels for Stability of Power System (전력계통 안전을 위한 공급예비력 적정수준에 대한 연구)

  • Ahn, Dae-Hoon;Kwon, Seok-Kee;Joo, Haeng-Ro;Choi, Eun-Jae
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.9
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    • pp.55-61
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    • 2008
  • Because of the high increasing rate of load demand these days the necessity of deciding what optimum reserve level is appropriate to most stably supply electricity is being emphasized. This research studies the downward tendency of reserve ratio by analyzing the trend of change of the network scale, reserve, and reserve ratio while optimum reserve has been increased as the network system scale grow up. This means, at this moment 6,000[MW] is optimum level for short term prospect of power supply and demand. And also, it has been analyzed that, as the annual peak load exceeded 50,000[MW], confirming the amount of optimum reserve level is more stable than keeping 10 to 12[%] reserve ratio.

Optimal Dispatch and Reserve Pricing Reflecting Opportunity Cost (기회비용을 반영한 최적급전과 예비력 가격설정)

  • Kim, Jong-Deoc;Bae, In-Su;Kim, Jin-O
    • Journal of Energy Engineering
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    • v.15 no.4
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    • pp.229-234
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    • 2006
  • Electric energy is too difficult to manage realtime for irregular change of load because of non-storage. In specially, operation of reserve is ancillary service to supply stably to defend large troubles in electric power system. But whole of electric power system brings to economical loss because of reserve operation. Therefore optimal reserve quantity and optimal reserve price are necessary in order to minimize loss. In this paper, we have presents optimal dispatch and reserve price consideration of opportunity cost.

Analysis on Power Transactions of Generation and Operating Reserve Based on Marginal Profits (한계이득 측면에서 분석한 발전 예비력 포함 전력거래)

  • Shin, Jae-Hong;Lee, Kwang-Ho
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.55 no.10
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    • pp.440-445
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    • 2006
  • As an electricity industry transforms into a competitive system, an electricity market revolves into a combined market consisting of generation and operating reserve. This paper presents a market model combined by an energy market and an operating reserve market. In a competitive structure, Gencos strive to choose strategic bidding parameters that maximize total profit resulting from an energy market and a reserve market. The primary goal of the paper is to analyze power transactions of generation and operation reserve based on marginal profits and capacity limits at NE(Nash Equilibrium). In case studies, the reserve market and the energy market are compared at the n from the viewpoints of marginal profits, prices and transaction quantities. It is shown that the marginal profit in an energy market is equal to that in a reserve market, and Gencos strategic bidding is greatly influenced by capacity limit.

A New Required Reserve Capacity Determining Scheme with Regard to Real time Load Imbalance

  • Park, Joon Hyung;Kim, Sun Kyo;Yoon, Yong Tae
    • Journal of Electrical Engineering and Technology
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    • v.10 no.2
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    • pp.511-517
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    • 2015
  • Determination of the required reserve capacity has an important function in operation of power system and it is calculated based on the largest loss of supply. However, conventional method cannot be applied in future power system, because potential grid-connected distributed generator and abnormal temperature cause the large load imbalance. Therefore this paper address new framework for determining the optimal required reserve capacity taking into account the real time load imbalance. At first, we introduce the way of operating reserve resources which are the secondary, tertiary, Direct Load Control (DLC) and Load shedding reserves to make up the load imbalance. Then, the formulated problem can be solved by the Probabilistic Dynamic Programming (PDP) method. In case study, we divide two cases for comparing the cost function between the conventional method and the proposed method.

Dynamic Reserve Estimating Method with Consideration of Uncertainties in Supply and Demand (수요와 공급의 불확실성을 고려한 시간대별 순동예비력 산정 방안)

  • Kwon, Kyung-Bin;Park, Hyeon-Gon;Lyu, Jae-Kun;Kim, Yu-Chang;Park, Jong-Keun
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.62 no.11
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    • pp.1495-1504
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    • 2013
  • Renewable energy integration and increased system complexities make system operator maintain supply and demand balance harder than before. To keep the grid frequency in a stable range, an appropriate spinning reserve margin should be procured with consideration of ever-changing system situation, such as demand, wind power output and generator failure. This paper propose a novel concept of dynamic reserve, which arrange different spinning reserve margin depending on time. To investigate the effectiveness of the proposed dynamic reserve, we developed a new short-term reliability criterion that estimates the probability of a spinning reserve shortage events, thus indicating grid frequency stability. Uncertainties of demand forecast error, wind generation forecast error and generator failure have been modeled in probabilistic terms, and the proposed spinning reserve has been applied to generation scheduling. This approach has been tested on the modified IEEE 118-bus system with a wind farm. The results show that the required spinning reserve margin changes depending on the system situation of demand, wind generation and generator failure. Moreover the proposed approach could be utilized even in case of system configuration change, such as wind generation extension.

Reserve Price Recommendation Methods for Auction Systems Based on Time Series Analysis (경매 시스템에서 시계열 분석에 기반한 낙찰 예정가 추천 방법)

  • Ko Min Jung;Lee Yong Kyu
    • Journal of Information Technology Applications and Management
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    • v.12 no.1
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    • pp.141-155
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    • 2005
  • It is very important that sellers provide reasonable reserve prices for auction items in internet auction systems. Recently, an agent has been proposed to generate reserve prices automatically based on the case similarity of information retrieval theory and the moving average of time series analysis. However, one problem of the previous approaches is that the recent trend of auction prices is not well reflected on the generated reserve prices, because it simply provides the bid price of the most similar item or an average price of some similar items using the past auction data. In this paper. in order to overcome the problem. we propose a method that generates reserve prices based on the moving average. the exponential smoothing, and the least square of time series analysis. Through performance experiments. we show that the successful bid rate of the new method can be increased by preventing sellers from making unreasonable reserve prices compared with the previous methods.

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A research of optimum supply reserve levels for stability of power system (전력계통 안정을 위한 공급예비력 적정수준에 대한 연구)

  • Ahn, Dae-Hoon;Kwon, Seok-Kee;Joo, Haeng-Ro;Shin, Jung-Sun
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • pp.61-65
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    • 2008
  • Because of the high increasing rate of load demand, these days the necessity of deciding what optimum reserve level is appropriate to most stably supply electricity is being emphasized. This research studies the downward tendency of reverve ratio by analyzing the trend of change of the network scale, reserve, and reserve ratio while optimum reserve has been increased as the network system scale grow up. This means, at this moment 6,000MW is optimum level for short term prospect of power supply and demand. And also, it has been analyzed that, as the annual peak load exceeded 50,000MW, confirming the amount of optimum reserve level is more stable than keeping 10 to 12% reserve ratio.

  • PDF