• Journal of Electrical Engineering and Technology
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• 제11권2호
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• pp.470-479
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• 2016

The model based method for energy saving of the separately excited DC motor drive system is proposed in the paper. The accurate power loss model is necessary for this method. Therefore, the adaptive tabu search algorithm is applied to identify the parameters in the power loss model. The field current values for minimum power losses at any load torques and speeds are calculated by the proposed method. The rule based controller is used to control the field current and speed of the motor. The experimental results confirm that the model based method can successfully provide the energy saving for separately excited DC motor drive. The maximum value of the energy saving is 48.61% compared with the conventional drive method.

• 한국지열·수열에너지학회논문집
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• 제9권1호
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• pp.1-7
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• 2013

With the architectural energy saving technique such as building insulation, airtightness etc., changing the indoor temperature and shortening the air conditioning time etc. are the good methods to practice energy saving in our lives. This study aims to seek a way to realize energy saving under investigation through a questionnaire survey about energy consumption condition and energy saving perception. 93% of the respondents recognized the need for energy saving, and 67% said more energy saving would possible in homes. Viable energy saving way was questioned by five steps method. More than 50% responded 'possible' or 'seems possible' at most of the items. Whereas less than 50% responded 'possible' or 'seems possible' at the items of 'lessening the cooling time' and 'lessening the shower time'. Ages of 50s who responded 'possible' or 'seems possible' was relatively less compared to 30s and 40s.

• 한국태양에너지학회 논문집
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• 제34권2호
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• pp.24-31
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• 2014

So many energy saving strategies to realize the low energy house are proposed in these days. Even if the energy saving performances are similar between the strategies, the costs are in abroad ranges. Therefore, the application of the energy saving strategies should be based upon two considerations; one is energy saving performance and the other is the cost. In this study, the decision making method for application of the passive design technologies in the design stage of the low energy apartment house are suggested. By utilizing the result of this study, practitioners can make an effective design alternatives which solve the conflicted values; energy saving and cost.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2004년도 추계학술대회 논문집
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• pp.27-31
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• 2004

This paper presents a nonconventional method for oft starting of three-phase induction motors, which achieved by flux weakening technique. flux weakening is not done by reducing the applied voltage as in the conventional methods, Flus weakening is achieved y increasing the supply frequency over the rated value while the voltage amplitude is kept constant. This method has advantage of reducing the stress on the electrical and mechanical systems. The feasibility of this basic idea has been confirmed through investigating the starting transient corresponding to this mode of operation. For this purpose, a rigorous state space mathematical model has been developed and simulated. The validity of the proposed method through the results from the mathematical model have been confirmed experimentally.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2003년도 ICCAS
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• pp.1736-1740
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• 2003

POSCO Kwang-Yang Works #2 Cold Rolling Mill RCL has the main hydraulic system that controlled on/off control method. In the aspect of the consumption of electrical energy this system has some problem. So, we present a continuous control method instead of on/off control method that controls the pressure of main hydraulic system with saving the electric energy.

• 한국통신학회논문지
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• 제40권7호
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• pp.1296-1306
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• 2015

오늘날 IP 네트워크에서 소모되는 에너지를 줄이기 위해 여러 곳에서 다양한 방법으로 연구되어 왔다. 본 논문은 다양한 에너지 프로파일을 갖는 IP 네트워크에서 에너지를 감소시키는 한 방법을 제안하고, 그 특성을 자세히 분석한다. 에너지 프로파일 기반 OSPF 라우팅 방식을 제안하면서, 경로 설정 시 기존 OSPF 방식의 metric과 네트워크 소자의 에너지 소모량에 가중치를 부여하여, 최대 에너지 절약 효과를 얻기 위해 다양한 경우에 대해서 분석한다. 그 결과 본 논문의 제안 방식은 IP 네트워크의 각 소자에 랜덤한 에너지 프로파일을 적용하면, 입력 라우터의 평균 입력 부하가 0.5일 때 기존의 운영 방식에 비해 67% 정도 에너지를 절약 할 수 있음을 확인한다. 그리고 본 방식의 알고리즘은 최소 에너지 소모가 되도록 라우팅하기 때문에 기존 라우팅 방식에 비해 경로의 홉 수가 다소 증가하고 있지만, 평균 홉 수 증가는 1.4홉 이내로 제한되고 있다. 그리고 본 방식이 실제 IP 네트워크 적용될 때, 에너지 절약 효과가 우수함을 나타낸다.

• 한국환경교육학회지:환경교육
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• 제19권3호
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• pp.102-113
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• 2006

The purpose of this study is to devise proper plans for sustainable energy management in schools through applying school eco-audit to energy field. This study is performed by literature review and the analysis of case study. This study analyzes the energy-saving model school according to the three cores of eco-audit such as school administration system, teaching-learning method, and ecological policy, and the result of the study is as followings. First, according to the analysis of school administration system for energy education programs, the participation of all the school staff is very low, and the democratic decision-making system is unsatisfactory. Second, according to the analysis of teaching-learning method, the program is mainly managed by teacher-oriented method not by learner-oriented one. The effect on the education of energy-saving program is a little improved in cognitive area, but is insufficient in affective area. Third, in the aspect of the ecological policy, the practical energy-saving effect in schools is unsatisfactory, and shows the difficulty of continuing application of the program. Consequently, it is desirable to integrate the energy-saving program with the eco-audit for sustainable energy management in schools. Implementation of the energy eco-audit in schools for the sustainable development education as teaching-learning method could achieve extended effect for the earth environmental conservation.

• 자원ㆍ환경경제연구
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• 제9권5호
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• pp.925-945
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• 2000

This paper analyses the impact of energy-saving investment on Greenhouse gas emissions using a model of energy demand in Korea. SUR method was employed to estimate the demand equation. The econometric estimates provide information about the energy price divisia index, sector income, and energy saving-investment elasticities of energy demand. Except for energy price divisia, the elasticities of each variable are statistically significant. Also, the price and substitution elasticities of each energy price are similar to the results reported by the previous studies. The energy-saving investment is statistically significant and elasticities of each sector is inelastic. Using the coefficient of energy-saving investment and carbon transmission coefficient, the amount of reduction of energy demand and the reduction of carbon emissions can be estimated. The simulation is performed with the scenario that the energy-saving investment increase by 10~50%, keeping up with Equipment Investment Plan of 30% increase in energy-saving investment by 2000. The results show that the reduction of energy demand measured as 11.2% based upon 1995's level of the energy demand, in industrial sector. Accordingly, the carbon emissions will be reduced by 11.3% based upon 1995's level of the carbon emissions in industrial sector.

• 전자공학회논문지
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• 제53권1호
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• pp.9-21
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• 2016

IP 네트워크에서 에너지 소모를 줄이기 위해 다양한 방법이 연구 되어 왔다. 본 논문에서는 다양한 에너지 프로파일을 갖는 IP 네트워크에서 2단계 라우팅 방식을 제시하고, 그 특성을 분석한다. 단계1의 라우팅 방식에서는 에너지 절약을 위해 기존 코스트 외에 에너지 코스트를 고려한 OSPF 라우팅이고, 단계2에서는 가능한 많은 코아 노드를 sleep 상태로 만든 후, sleep 노드로 영향을 받는 경로만 재 라우팅 하는 방식을 적용한다. 이때 단계2에서 에너지 절약 특성과 네트워크 레벨의 QoS 보장을 위한 방법으로, 재 라우팅 시 허용 가능한 증가 홉 수와 링크 및 노드의 이용률을 제한함으로써 에너지 효율 개선 및 네트워크 레벨의 지연 특성을 동시에 만족시킬 수 있다는 것을 확인한다. 또 sleep 모드로 둘 코아 노드를 선정하는 방법에 따라 에너지 절약 효율 및 지연 특성이 다르며, MP (minimum_path)에 기초하여 sleep 상태로 만들 코아 노드를 선정하는 방식이 우수함을 나타낸다.

• International Journal of Internet, Broadcasting and Communication
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• 제7권2호
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• pp.36-40
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• 2015

In Korea, new total energy-saving solution has planned to build test-bed in underground subway station. Breaking energy is one of the most energy saving method in railway, but it has not be fully used up for economical purpose. This paper demonstrates on energy saving technology application including breaking energy and heating energy to underground subway station. It also offer solution of optimization of power energy flow. Moreover, economic feasibility analysis performed for undergound test bed constuction.