• 동력기계공학회지
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• 제16권2호
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• pp.60-65
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• 2012

Pneumatic actuators are clean, lightweight, and can be easily serviced, whereas low energy efficiency has been considered as a critical shortcoming compared with corresponding hydraulic and electrical actuators. This study describes a new design method of pneumatic cylinder driving apparatus by lowering a supply pressure. The simulation study demonstrates that the designed system with the proposed method can operate at the smaller energy consumption state compare to the designed system with the conventional method for the specified working conditions.

• KIEAE Journal
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• 제15권4호
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• pp.77-84
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• 2015

Purpose: In 2008, As the green growth policy was presented, Green Building is made any effort to propagation. In this paper, the respective technologies that are able to considerably reduce the energy demands for heating, cooling, hot-water, lighting and ventilation among the variety of technologies were selected. Method: Design factors such as (1) External insulation, (2) Triple glazing window, (3) LED lighting, (4) External venetian blind, (5) Geothermal and (6) Heat recovery ventilator were derived. In addition, energy saving effects in terms of energy demand, energy consumption and energy cost were investigated using EnergyPlus, building energy analysis tool. Result : The results were as follows. (1) It can be seen that high insulated triple glazing window, heat recovery ventilator and external insulation technology is excellent for energy demand. (2) Unlike energy demand, saving effect of energy consumption and energy cost was shown in order of Geothermal > Triple Window > Heat recovery Ventilation> Insulation> LED Lighting > EVB Blind.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.819-824
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• 2008

Energy consumption in Korea and Japan has already progressed to high level. Especially, it will be important to take up the effort to achieve further energy savings in residential sector that has significant increase both nations. For this reason, research for energy consumption and saving method in residential sector compare Korea with Japan that of similar data to grasps the direction for energy savings. In addition for introduction of distributed energy system to residential sector, such as apartment house, the electricity and gas demand was simulated. To be more specific, several key characteristics were studied, such as housing type housing scale and width of common space.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2005년도 학술대회 논문집
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• pp.95-99
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• 2005

This paper presents a general proposal to design and calculate the performance of a tubular permanent magnet linear generator treated here on the basis of the Finite Element Method. Optimizing the linear generator dimensions reduces the cogging force, which occurs due to the interaction between stator teeth and the permanent magnets. The generated AC voltage is analyzed and evaluated for both no load and load cases to take the armature reaction effects on the air gap flux density. A repetitive routine is followed to calculate the output AC voltage from the change of flux and the speed of the single-phase linear generator. The AC output voltage is calculated for different resistive loads, and hence, the linear generator load characteristic is obtained. The designed linear generator is capable to generate an output power of 5.3kW with AC output voltage of 222V with an efficiency of 96.8% at full load of 23.8A. The full load current is chosen based on the thermal properties of the coil wire insulations.

• 한국태양에너지학회 논문집
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• 제28권6호
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• pp.15-23
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• 2008

The article deals with system technology of a new solar heating system which systematically combines exiting solar collector technology, auxiliary electrical water heating, floor heating system and well insulated construction method and its application of this system to apartment house heating system in the cold region, and also analyzed performance of the new system in terms of technical and economic feasibility. Results shows that energy efficiency approaches up to 50% of the energy consumption of local construction from 1980 to 1981. The implementation of "DQ technology" to floor heating system achieved from 79% to 85% of the energy-saving benefits comparing to other housing units which were supplied by the local district heating plant.

• 정보처리학회논문지A
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• 제16A권1호
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• pp.27-34
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• 2009

최근 디지털 시스템 응용의 복잡성이 증가하면서, 고성능화와 전력 소모 절감은 중요한 문제로 대두되고 있다. 전력 소모를 줄이기 위한 방법으로, 프로세서의 저 전력화 또한 미세 공정의 개발과 함께 다양하게 접근되고 있으며, 이러한 결과 모바일 시스템의 시장 확대가 이루어지고 있다. 본 논문은 이러한 프로세서에서 소모되는 전력 중 데이터 캐시의 전력 손실을 줄이기 위하여 데이터 캐시의 웨이 중 필요로 하는 부분을 예측하여 선택적으로 프리자치 하도록 하는 전력 소모 개선 방법을 제안하였으며, 접근하는 웨이에 대한 예측이 성공했을 경우에는 에너지를 절감하면서 지연이 발생하지 않는 빠른 접근이 이루어지게 하고, 실패하였을 경우에도 최소한의 시간 지연으로 해당되는 웨이의 접근이 이루어지게 하였다. 시뮬레이션을 통한 검증 결과 웨이 예측 기법만을 사용한 경우에 대비하여 평균 10.2% 의 전력을 절감할 수 있었으며, 일반적 캐시에 비하여는 평균 56.4%의 전력을 절감할 수 있었다.

• 설비공학논문집
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• 제14권11호
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• pp.981-988
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• 2002

Generally, the term "energy saving is economical" is appropriate for the national view point and for design and assessment of one system, but not appropriate when choosing the system by comparing alternative systems in the early design step. Sometimes, non-energy saving system is more economical than energy saving system because of the price of electricity, gas or oil, which are used for operating the air conditioning system. Therefore, when designing the system, we should consider the efficient alternatives through economic assessment of energy saving method. However, research on non-operating number control of the system is not sufficient because it is more common to use operating number control of the system for most economic assessment of air conditioning system. For this reason, this research can provide the economics through operating number control as basic design data. The data obtained through assesment of Life Cycle Cost based on amount of yearly energy use, were produced by system simulation of HASP/ACLD/8501 and HASP/ACSS/8502 for six alternative heating/cooling systems based on constant air volume conditioning system, which is widely used for medium and large office buildings in Busan.

• Journal of Communications and Networks
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• 제18권4호
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• pp.610-618
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• 2016

A green cognitive radio network (CRN), characterized by base stations (BSs) that conserve energy during sleep periods, is a promising candidate for realizing more efficient spectrum allocation. To improve the spectrum efficiency and achieve greener communication in wireless applications, we consider CRNs with an long term evolution advanced (LTE-A) structure and propose a novel energy-saving strategy. By establishing a type of preemptive priority queueing model with a single vacation, we capture the stochastic behavior of the proposed strategy. Using the method of matrix geometric solutions, we derive the performance measures in terms of the average latency of secondary user (SU) packets and the energy-saving degree of BSs. Furthermore, we provide numerical results to demonstrate the influence of the sleeping parameter on the system performance. Finally, we compare the Nash equilibrium behavior and social optimization behavior of the proposed strategy to present a pricing policy for SU packets.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1992년도 하계학술대회 논문집 B
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• pp.1203-1205
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• 1992

Due to poor energy resources, the importance of energy saving has been greatly emphasized. It can be one method of energy saving to reduce the power. The AC adjustable speed drive systems show excellent efficiency, which have been developed in recent years. The adjustable speed drive system improves the efficiency in lightly load condition and extend the life span of motor by limiting the over-current at starting. The main topic of study is the results of energy saving and emergency transfer.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.480-483
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• 2008

The cold-air distribution system is expected as an efficient method to reduce energy consumption in the air-conditioning system. We introduced some control strategies for the system by summarizing some references in the view point of energy saving. Direct digital control is specially emphasized as an important control technique for the system. Some drawbacks which habe been conventionally mentioned to apply the cold-air distribution to real fields can be solved by using the technique. The control strategy which is introduced in here will be available to build control system for the air-conditioning based on the cold-air distribution for energy saving.