• Title/Summary/Keyword: demand control

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Reducing Peak Cooling Demand Using Building Precooling and Modified Linear Rise of Indoor Space Temperature (건물예냉과 실내온도의 선형상승에 의한 피크냉방수요 저감)

  • Lee, Kyoung-Ho;Yang, Seung-Kwon;Han, Seung-Ho
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.22 no.2
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    • pp.86-96
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    • 2010
  • The paper describes development and evaluation of a simple method for determining gradient of modified linear setpoint variation to reduce peak electrical cooling demand in buildings using building precooling and setpoint adjustment. The method is an approximated approach for minimizing electrical cooling demand during occupied period in buildings and involves modified linear adjustment of cooling setpoint temperature between $26^{\circ}C$ and $28^{\circ}C$. The gradient of linear variation or final time of linear increase is determined based on the cooling load shape in conventional cooling control having a constant setpoint temperature. The potential to reduce peak cooling demand using the simple method was evaluated through building simulation for a calibrated office building model considering four different weather conditions. The simple method showed about 30% and 20% in terms of reducing peak cooling demand and chiller power consumption, respectively, compared to the conventional control.

Demands and Payments under Demand Guarantees - Focused on the URDG 758 (청구보증상 지급청구와 지급- URDG758을 중심으로 -)

  • Heo, Hai-Kwan
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.51
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    • pp.213-239
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    • 2011
  • This article examines two important issues of the demand for payment by the beneficiary and the payment by the guarantor to the beneficiary under the revised Uniform Rules for Demand Guarantee (URDG) published by ICC, which are called URDG 758 and effected on July 1, 2010. Here, after first briefly defining the concept and nature of the demand for payment, this article discusses various issues surrounding the demand: By whom, where and how the demand has to be made; which documents are required in demanding the payment; how much amount can be demanded and paid; when and where the payment has to be made and which currency has to be used for the payment. The demand for payment has to be made by the beneficiary to the guarantor on or before expiry of the guarantee at the place of issuance of the guarantee unless any other place is specified in the guarantee. The demand has to be made in paper form unless the guarantee requires an electronic form. Unless otherwise expressly stipulated in the guarantee, the demand must be supported by a statement by the beneficiary indicating the applicant is in breach of the underlying contract. Also the demand must identify the guarantee under which it is made, and the time for examination by the guarantor starts on the date of identification. The demand cannot be for more than the amount available under the guarantee. When the demand is complying the guarantor must pay the amount demanded. The payment has to be made at the branch or office of the guarantor that issued the guarantee unless any other place is indicated in the guarantee. The payment has to be made in the currency specified in the guarantee, unless the guarantor is unable to make payment in that currency due to an impediment beyond its control or any illegality under the law of the place for payment. In case of "extend or pay" or "pay or extend" demands, the demand is deemed to be withdrawn if the extension is granted. But if not, the demand has to be paid without any further demand by the beneficiary.

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Development of Daily Peak Power Demand Forecasting Algorithm with Hybrid Type composed of AR and Neuro-Fuzzy Model (자기회귀모델과 뉴로-퍼지모델로 구성된 하이브리드형태의 일별 최대 전력 수요예측 알고리즘 개발)

  • Park, Yong-San;Ji, Pyeong-Shik
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.63 no.3
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    • pp.189-194
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    • 2014
  • Due to the increasing of power consumption, it is difficult to construct accurate prediction model for daily peak power demand. It is very important work to know power demand in next day for manager and control power system. In this research, we develop a daily peak power demand prediction method based on hybrid type composed of AR and Neuro-Fuzzy model. Using data sets between 2006 and 2010 in Korea, the proposed method has been intensively tested. As the prediction results, we confirm that the proposed method makes it possible to effective estimate daily peak power demand than conventional methods.

A Study on Designing a Market Driven Demand Response System (시장 기반의 수요관리 기법 Demand Response System 설계 방안 연구)

  • Yu, In-H.;Lee, Jin-K.;Kim, Sun-I.;Ko, Jong-M.
    • Proceedings of the KIEE Conference
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    • 2002.11b
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    • pp.384-386
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    • 2002
  • As restructuring in power industry has introduced competitive markets, a new method on demand side management has been developed. Many programs using the method were developed with providing several choices for customer. Nowadays the programs are called demand response as the load management is done by customer's responding to the market price signal. It was proven that the method was effective for demand control with the active consumer's attending for the program. This paper analyses the perspective and the requirement for designing the demand response system.

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Development of Daily Peak Power Demand Forecasting Algorithm Considering of Characteristics of Day of Week (요일 특성을 고려한 일별 최대 전력 수요예측 알고리즘 개발)

  • Ji, Pyeong-Shik;Lim, Jae-Yoon
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.63 no.4
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    • pp.307-311
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    • 2014
  • Due to the increasing of power consumption, it is difficult to construct accurate prediction model for daily peak power demand. It is very important work to know power demand in next day for manager and control power system. In this research, we develop a daily peak power demand prediction method considering of characteristics of day of week. The proposed method is composed of liner model based on AR model and nonlinear model based on ELM to resolve the limitation of a single model. Using data sets between 2006 and 2010 in Korea, the proposed method has been intensively tested. As the prediction results, we confirm that the proposed method makes it possible to effective estimate daily peak power demand than conventional methods.

Development of Daily Peak Power Demand Forecasting Algorithm using ELM (ELM을 이용한 일별 최대 전력 수요 예측 알고리즘 개발)

  • Ji, Pyeong-Shik;Kim, Sang-Kyu;Lim, Jae-Yoon
    • The Transactions of the Korean Institute of Electrical Engineers P
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    • v.62 no.4
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    • pp.169-174
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    • 2013
  • Due to the increase of power consumption, it is difficult to construct an accurate prediction model for daily peak power demand. It is very important work to know power demand in next day to manage and control power system. In this research, we develop a daily peak power demand prediction method based on Extreme Learning Machine(ELM) with fast learning procedure. Using data sets between 2006 and 2010 in Korea, the proposed method has been intensively tested. As the prediction results, we confirm that the proposed method makes it possible to effective estimate daily peak power demand than conventional methods.

A Study on the Demand and Status of Distribution and Production of Landscape Plants (한국의 조경수 생산과 유통현황 및 수요분석)

  • Kim, H.J.;Lee, T.Y.;Kwon, Y.H.
    • Journal of Practical Agriculture & Fisheries Research
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    • v.13 no.1
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    • pp.83-102
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    • 2011
  • The purpose of this study carried out to analyze production status, pricing trend and distribution status of landscape plants, so that it could predict the demand of landscape plants for the balance of supply and demand. The production amount of landscape plants made constantly increased. The annual output of shrubs increased more higher than that of trees. The prices of trees have raised consistently, but shrubs were susceptible to price fluctuations. And there were still many problems in the distribution structure. The landscaping work has focused on the metropolitan area. And large-scale nationwide projects were scheduled for coming years, so the demand of landscape plants was expected to expend. However, the lack of increase in production amounts of landscape plants, it is cause to supply problems. So, demand forecast was necessary to control the production of landscape plants.

Research for Signal Interfaces between DOORS of DRIVERLESS TRAIN and PSD Control (무인운전 차량의 도어 및 PSD 제어 신호에 대한 연구)

  • Lee, Hee-Chang;Kim, Dong-Il;Chun, Sang-Hun
    • Proceedings of the KSR Conference
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    • 2010.06a
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    • pp.857-865
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    • 2010
  • Recently the demand of the driverless rolling stock is increasing with advancement of the stable communication technique and control technique. The automatic train operating system has advantages which takes low operating cost and is able to dispose elastically in demand. Beside it provides high safety and effectiveness because it will be able to control power, signal and communication system from Operation Control Center and the safety and effectiveness are high. The establishment of PSD, Platform Screen Door, is advanced in the goal which is passenger safety, fire protection, noise and dust reduction etc. When but, two advanced systems also have risks of operation delay and accident when two systems are not controlled smoothly. Thus, I'll introduce control method between onboard controller, door control unit in rolling stock and PSD controller to help system design.

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Development of Water Management System for Optimal Operation and Control in Wide-area Waterworks (광역상수도의 최적운영 및 제어를 위한 수운영시스템 개발)

  • 남의석;우천희;김학배
    • Journal of Institute of Control, Robotics and Systems
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    • v.9 no.7
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    • pp.489-497
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    • 2003
  • A water management system is developed to reduce the unit cost of production in wide-area waterworks. Improving productivity in waterworks is to save power rate. We suggest a method to schedule the supply of water according to the time-varying power rate and pump control scheme. Water pipeline analysis package (SynerGEE Water) is utilized to obtain optimal pump control solution adaptation to water demand. Our evaluation results show that developed scheme is more efficient than the conventional.

The Development of Intelligent Direct Load Control System

  • Choi, Sang Yule
    • International journal of advanced smart convergence
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    • v.4 no.2
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    • pp.103-108
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    • 2015
  • The electric utility has the responsibility of reducing the impact of peaks on electricity demand and related costs. Therefore, they have introduced Direct Load Control System (DLCS) to automate the external control of shedding customer load that it controls. Since the number of customer load participating in the DLC program are keep increasing, DLCS operators a re facing difficulty in monitoring and controlling customer load. The existing DLCS needs constant operator intervention, e.g., whenever the load is about to exceed a predefined amount, it needs operator's intervention to control the on/off status of the load. Therefore, DLCS operators need the state-of-the-art DLCS, which can control automatically the on/off status of the customer load without intervention as much as possible. This paper presents an intelligent DLCS using the active database. The proposed DLCS is applying the active database to DLCS which can avoid operator's intervention as much as possible. To demonstrate the validity of the proposed system, variable production rules and intelligent demand controller are presented.