• Environmental and Resource Economics Review
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• v.16 no.4
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• pp.901-922
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• 2007

To see how the electricity demand for air-conditioning responds to weather condition and what kind of weather condition works better in forecasting maximum daily electricity demand, four different regression models, which are linear, exponential, power and S-curve, are adopted. The regression outcome turns out that the electricity demand for air-conditioning is inclined to rely on the exponential model. Another major discovery of this study is that the electricity demand for air-conditioning responds more sensitively to the weather condition year after year along with the higher non-air-conditioning electricity demand. In addition, it has also been found that the discomfort index explains the electricity demand for air-conditioning better than the highest temperature.

• KIEE International Transactions on Power Engineering
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• v.5A no.4
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• pp.403-411
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• 2005

At present, the Cournot model is one of the most commonly used theories to analyze the gaming situation in an oligopoly type market. However, several problems exist in the successful application of this model to the electricity market. The representative one is obtaining the inverse demand curve able to be induced from the relationship between market price and demand response. In the Cournot model, each player offers their generation quantity to obtain maximum profit, which is accomplished by reducing their quantity compared with available total capacity. As stated above, to obtain the probable Cournot equilibrium to reflect the real market situation, we have to induce the correct demand function first of all. Usually the correlation between price and demand appears over the long-term through statistical data analysis (for example, regression analysis) or by investigating consumer utility functions of several consumer groups classified as residential, industrial, and commercial. However, the elasticity has a tendency to change continuously according to the total market demand size or the level of market price. Therefore it should be updated as the trading period passes by. In this paper we propose a method for inducing and updating this price elasticity of demand function for more realistic market equilibrium.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.63 no.4
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• pp.455-460
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• 2014

South Korea's power consumption is increasing every year. For stable electric power supply, more generation facilities are needed. But it is not easy to build nuclear power generation facilities, so provision of renewable energy is thought of as the solution. For the system's stable management, practical use of energy storing system is needed. Currently, pumping up electric power station is considered most useful. In this study, we have calculated the least amount of energy storing device by considering the renewable energy, HVDC, and change in power for the appliance of ESS in Jeju system, according to The 6th Basic Plan for Long-term Electricity Supply and Demand. Also we have calculated the amount of the battery and about the load equalizing effect to use battery as power storing device. Finally, we have calculated the reduction of electricity generation and the reduction of $CO_2$ emission with this study.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.106-111
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• 1992

In order to achieve stable and efficient use of energy at iron and steel works, a model for the prediction of supply and demand of electric power system is developed on the basis of the information on operation and particular patterns of electric power consumption. The optimal amount of electric power to be purchased and the optimal fuel allocation for the in-house electric power plants are also obtained by a mixed-integer linear programming(MILP) and a nonlinear programming (NLP) solutions, respectively. The validity and the effectiveness of the proposed model are investigated by several illustrative examples. The simulation results show the satisfactory energy saving by the optimal solution obtained through this research.

• Journal of Electrical Engineering and Technology
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• v.10 no.3
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• pp.859-864
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• 2015

This paper analyzes the impact of Plug-in Electric vehicles(PEVs) on power demand and voltage change when PEVs are connected to the domestic distribution system. Specifically, it assesses PEVs charging load by charging method in accordance with PEVs penetration scenarios, its percentage of total load, and voltage range under load conditions. Concretely, we develop EMTDC modelling to perform a voltage distribution analysis when the PEVs charging system by their charging scenario was connected to the distribution system under the load condition. Furthermore we present evaluation algorithm to determine whether it is possible to adjust it such that it is in the allowed range by applying ULTC when the voltage change rate by PEVs charging scenario exceed its allowed range. Also, detailed analysis of the impact of PEVs on power distribution system was carried out by calculating existing electric power load and additional PEVs charge load by each scenario on new-town in Korea to estimate total load increases, and also by interpreting the subsequent voltage range for system circuits and demonstrating conditions for countermeasures. It was concluded that total loads including PEVs charging load on new-town distribution system in Korea by PEVs penetration scenario increase significantly, and the voltage range when considering ULTC, is allowable in terms of voltage tolerance range up to a PEVs penetration of 20% by scenario. Finally, we propose the charging capacity of PEVs that can delay the reinforcement of power distribution system while satisfying the permitted voltage change rate conditions when PEVs charging load is connected to the power distribution system by their charging penetration scenario.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.395-398
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• 2001

Recently, the increasing need for internet and the activation of hiring business of communication line makes the demand for OPGW cable which can construct the optical communication network in the basis of existing overhead power transmission line. Especially, the demand is focused on the high fiber count OPGW due to high capacity transmission. In step with the trend toward high fiber count cable we have developed the Stainless Steel Loose Tube type OPGW within which have 144core firstly in KOREA. This paper describes the cable design and manufacturing process which gives the stable operation in very severe conditions and the long-term reliability test results conducted in according to dominant specification IEEE Std. 1138-1194.

• Proceedings of the Korea Information Processing Society Conference
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• 2006.11a
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• pp.613-616
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• 2006

본 연구에서는 신 수요관리 기법인 DR(Demand Response)시스템의 개발 및 운영현황을 알아 보았다. 특히 DR 시스템의 구성 방안과 각 모듈들의 설계시 검토 및 요구 사항을 분석하였다. 그리고 공급자와 수요자를 잇는 네트워크는 국가전력 IT과제에서 Portal의 개념을 도입하여 CP(Consumer Portal) 및 DP(Device Portal)에 의한 채널의 표준화를 시도하고 있다. DR의 개념은 수요관리와 가격 응답으로 공급자의 관리 기능과 가격 또는 인센티브 등이 제공되는 수요자가 참여하는 서비스의 양면을 가지고 있다. 이와 같은 시스템이 개발될 경우에는 전력사와 소비자 사이의 양방향 통신 채널이 형성되고 따라서 실시간 수요의 측정이 가능해진다. 또한 이를 토대로 DR 시스템을 사전 검토 및 계획상의 문제점을 분석하여 한국형 DR 시스템의 개발에 대한 기반을 조성하고자 하였다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.16 no.3
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• pp.1047-1062
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• 2022

Differential power analysis (DPA) is disturbed by ghost peaks. There is a phenomenon that the mean absolute difference (MAD) value of the wrong key is higher than the correct key. We propose a compressed key guessing space (CKGS) scheme to solve this problem and analyze the AES algorithm. The DPA based on this scheme is named CKGS-DPA. Unlike traditional DPA, the CKGS-DPA uses two power leakage points for a combined attack. The first power leakage point is used to determine the key candidate interval, and the second is used for the final attack. First, we study the law of MAD values distribution when the attack point is AddRoundKey and explain why this point is not suitable for DPA. According to this law, we modify the selection function to change the distribution of MAD values. Then a key-related value screening algorithm is proposed to obtain key information. Finally, we construct two key candidate intervals of size 16 and reduce the key guessing space of the SubBytes attack from 256 to 32. Simulation experimental results show that CKGS-DPA reduces the power traces demand by 25% compared with DPA. Experiments performed on the ASCAD dataset show that CKGS-DPA reduces the power traces demand by at least 41% compared with DPA.

• Journal of Advanced Information Technology and Convergence
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• v.10 no.2
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• pp.91-101
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• 2020

Recently, the demand for high penetration of variable renewable energy (VRE) penetration in a power system is increased. In consequence, distribution systems including microgrids confront the increased installation of VRE-based distributed generation. Despite of the high demand of VRE-based distributed generation in a distribution system, the installation of photovoltaic (PV) system in a distribution system has been restricted by various problems. In other words, the hosting capacity for high VRE penetration in a distribution system is limited. This paper analyzes the improvements of hosting capacity VRE penetration of stand-alone microgrid (SAMG) with energy storage system (ESS) by considering virtual-slack (VS) control based on power sensitivity. With the pre-defined power sensitivity, the ESS operates as virtual slack in the SAMG by controlling its bus voltage and phase angle indirectly. Therefore, the ESS enables the increase of VRE penetration in the SAMG. The proposed VS control is realized by analyzing the ESS as a virtual slack in power flow analysis based on power sensitivity. Then its validity is demonstrated with the case study on the SAMG in South Korea with practical data.

• Advances in Energy Research
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• v.5 no.1
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• pp.57-64
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• 2017

Electricity is basic need for country development. But at the present time proper planning and policy is require at high pace for power generation network extension due to the increasing population growth rate. Present study aimed to analyze the present and future demand for electricity at household level in Province of Balochistan of Pakistan via simulation modeling. Data of year 2004-2005 was used as baseline data for electricity consumption to predict future demand of electricity at both rural and urban domestic level up to subsequent 30 years, with help of LEAP software. Basically three scenarios were created to run software. One scenario was Business-As-Usual and other two were green scenarios i.e., solar and wind energy scenarios. Results predicted that by using alternative energy sources, demand for electricity will be fulfill and will also reduce burden on non-renewable energy sources due to the greater potential for solar and wind energy present in Balochistan.