• International Journal of Air-Conditioning and Refrigeration
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• 제8권2호
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• pp.29-38
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• 2000

Air side heat transfer and pressure drop for f 9.52 fin-tube heat exchanger with various types of slit and louver fins were measured, and compared with wave-slit fin. Longitudinal and transverse tube spacings of the heat exchangers are 21.65 mm and 25mm respectively. Actual heat exchanger was tested using water, and the tests were performed for 2 row heat exchangers with 3 different fin spacings, 1.3, 1.5 and 1.7 mm. The overall performance of the enhanced fins was evaluated by comparing heat transfer coefficient with respect to fan power

• 연구논문집
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• 통권34호
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• pp.39-46
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• 2004

The compressors in the air conditioner have the role of the pressurization and circulation of the refrigerant. The hermetic reciprocating compressors driven by rotary motor have been used for the air conditioner. The linear compressor has very simple structure and enhancement in the efficiency in comparison to that of conventional reciprocating compressor. The linear compressors are widely used for the small cryogenic refrigerator (below 1 kW), such as the Stirling refrigerator and pulse tube refrigerator. In the cryogenic application, the pressure ratio of the linear compressor is below 1.5, but the linear compressor for the air conditioner should overcome the high pressure ratio and the large pressure difference between the each sides of the piston. The resonance characteristics of the linear compressor has the significant impacts on the power consumption. To minimize the power consumption, the linear compressor should be operated at the resonance point. In the resonance characteristics, the role of the mechanical and gas spring should be considered. In present study, the cycle of the analysis of the vapor compression refrigeration cycle with the different refrigerants (R134a, R4l0a, R600a) and the designs of the linear compressor are performed. The effects of the stiffness of the mechanical spring on the electromagnetic forces would be discussed. Finally, the results show the design specification of the linear compressor for the air conditioner.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1213-1216
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• 1996

This paper describes a precise temperature control method for refrigerating and air conditioning systems. The control technique is based on the optimal servo control design method and the control algorithm is implemented on a personal computer. To control the precise temperature, two actuators such as an inverter for the compressor speed control and a stepping motor for regulating the expansion valve are used. The superheat and evaporator temperatures are chosen as the system output. So a multivariable system which has two inputs and two outputs to be controlled. The complicative model is identified by using an ARX(Auto Regressive eXogenous) model and the controller is designed by using the Matlab software.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2017년도 전력전자학술대회
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• pp.292-293
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• 2017

In the single type mechanical compressor mounted on the refrigerated vehicle, one compressor is responsible for the refrigerator function of the air conditioner and the refrigerator, so it is difficult to maintain a certain refrigeration temperature in the summer. Particularly, in a mechanical compressor using an engine as a power source, the refrigeration quality is deteriorated due to unstable rotation of the engine. In this paper, we propose a three - phase inverter of a dual compressor system that uses an electric compressor separately from a mechanical compressor of a refrigerated vehicle. The output characteristics of the developed inverter were verified through a vehicle air conditioning simulator.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2002년도 유체기계 연구개발 발표회 논문집
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• pp.161-164
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• 2002

Present condition of small fan used in appliances and IT industry is briefly reviewed. Here, fans used in refrigerator, air-conditioner, vacuum cleaner, microwave oven and computer are surveyed. Also some comments about the issue of each fan is described.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2007년도 추계학술대회 논문집
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• pp.974-981
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• 2007

Seoul Metro has operated the air cooling equipment established in a machine room of a station building to improve our services focused on our customers who use Seoul Metro during the summer season. However, a new set of problems has arisen with the cooling tower to support a heat exchange of cooling water. One of them is loss of efficiency in the air conditioner. The leading cause of this problem is that we use an underground type of the cooling tower. As the machine room of a station building is located in the underground of inner city because of the nature of the subway, it is difficult to establish the cooling tower on the ground. The underground structure of the No. $1{\sim}4$ subway line is unsuitable for the location requirements of the underground type of the one because it has a limited space to set up the air cooling equipment, for example, the cooling tower and a ventilating opening. As a result of such an unfavorable condition, the cooling tower doesn't work efficiently and the warmth of cooling water because of insufficiency of a heat exchange and a refrigerator's technical obstacle such as a high-temperature and a high-pressure has arisen. Accordingly, the efficiency of the air conditioning is getting lower and lower. Another problem is too wasteful with water. Each station uses the water over 30 tons every day with waterworks to replenish the cooling tower such as a evaporation, a scattering and a distribution of water. Nevertheless, the more an air conditioner increase, the more the use of water supply increase. For this reason, we can't help wasting an enormous amount of water and discharging the congelation of a low temperature(about $15^{\circ}C$) occurred in a heat exchanger inside an air conditioner. The purpose of this study is to analyze the utility of congealing water to improve efficiency of the air cooling equipment and save energy as a supplementary water for the cooling tower.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1994년도 박판성형기술의 진보
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• pp.199-230
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• 1994

The blanking sequence of refrigerator and air-conditioner compressor-motor-core has been determined by trial and error. To improve such problem, 2d-analysis using ANSYS to verify the deformation state has been done firstly. And 3d-analysis following up the real process has been done. Additionally, verified the 3-d analysis result using S/W LS-DYNA.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 추계학술대회 논문집 전력기술부문
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• pp.216-218
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• 2006

Economy of world has grown rapidly. This growth has increased the ownership of household electrical appliances including room air conditioners. The number of users of air conditioners is predicted to grow dramatically in the future. This paper discusses the present status of residential appliance energy efficiency standards around the world. The study found that the energy efficiency standards for room all conditioners would mitigate a significant amount of emissions in Korea.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 춘계학술대회논문집
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• pp.622-627
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• 2003

Until now, product mostly has revealed physical quantities created by the standpoint of engineers. Consumers, however, perceive and evaluate products on the non-physical characteristics, such as feelings, emotions, and experiences in different social and cultural situations. Especially, for the household appliances fur instance air-conditioner or refrigerator, the sound is heavily related to the satisfaction of a customer who is a real user of the product and is very important factor to decide purchasing as well as visual design. Therefore, in this research, the general tendency of consumer's psychology was investigated for the appliances. And also, in order to obtain clear guidelines for sound manipulation, the characteristics of the sound of air-conditioning systems and refrigerators were compared with others. Since it is important to overcome the discrepancy between engineering and marketing, the relevance of sound manipulation must be documented from the consumer's perspective. That is the reason why we conducted a consumer and marketing oriented study.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2008년도 하계종합학술대회
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• pp.499-500
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• 2008

In this paper, we design and implement the monolithic power factor correction IC for system power modules using a high voltage(50V) CMOS process. The power factor correction IC is designed for power applications, such as refrigerator, air-conditioner, etc. It includes low voltage logic, 5V regulator, analog control circuit, high-voltage high current output drivers, and several protection circuits. And also, the designed IC has standby detection function which detects the output power of the converter stage and generates system down signal when load device is under the standby condition. The simulation and experimental results show that the designed IC acts properly as power factor correction IC with efficient protective functions.