• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.435-436
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• 2007

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.694-695
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.719-720
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• 2010

• Korean Journal of Computational Design and Engineering
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• v.18 no.2
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• pp.120-128
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• 2013

Recently, the importance of the HVAC system (Heating, Ventilating and Air Conditioning System) is growing because comfortable working environment has emerged as important element for enhancing work efficiency. HVAC system is a general term of a system that collectively creates desired temperature and state through heating and air conditioning. HVAC system consists of many objects, so it requires a lot of constraints for its effective operation. Thus, specific strategy is needed for an optimal operation of HVAC System for plant. In this paper, manufacturing plants which have HVAC systems has been modeled and the objective function and constraints for an effective operation have been defined. And new strategy for an effective operation of HVAC system with energy simulations has been proposed.

• Fire Science and Engineering
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• v.18 no.4
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• pp.78-85
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• 2004

This research analyzes Clean Room accidents, and presents research Clean Room, major fire prevention standards of Clean Room (FM, IRI, and NFPA Code), various results from Fire Simulation of analysis. The results are : the smoke diffusion is very quick coupled with the Heating, Ventilating, and Air Conditioning (HVAC) systems under fire ; the possibility of getting the result and the possibility the role of the Sprinkler systems to reduce the diffusion of the smoke. We learn about the importance to stop operating Heating, Ventilating, and Air Conditioning (HVAC) systems and to operate the Sprinkler system for securing safety with fire detection. Therefore, This research will be contributing to secure safety of Clean Room.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.18 no.1
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• pp.115-121
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• 2004

In this paper, a new distributed intelligent control module based on LonWoks fieldbus for air handling unit(AHU) of heating, ventilating and air-conditioning(HVAC) is proposed to replace with a conventional direct digital control(DDC) system with 32 bit microprocessor. The proposed control architecture has a excellent features such as highly compact and flexible function design, a low priced smart front-end and reliable performance with various functions. This also addresses issues in control network configuration, logical design of field devices by S/W tool, Internet networking and electronic element installation. Experimental results for showing the system performance are also included in this paper.

• Proceedings of the KIEE Conference
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• 2006.10c
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• pp.303-305
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• 2006

본 논문은 HVAC(heating, ventilating, and air conditioning) 시스템의 효율성과 안정성에 기초하여, 과열도와 저압을 제어하는 Multi Fuzzy 제어기 설계를 제안한다. HVAC 시스템은 Compressor(압축기), Condenser(응축기), Evaporator(증발기), Expansion Valve(확장 밸브) 로 구성되며, 각각의 기기에 대한 제어가 독립적으로 이루어져 있다. 기존의 제어가 한 제어기를 사용한 단일방식으로 이루어지다보니 HVAC 시스템의 특성인 냉매의 상태가 달라지면 시스템 전반적으로 그 영향이 파급되는 부분까지 고려를 해 주지 못하고, 제어기의 성능이 효율적이고 안정적이지 못했다. 본 논문에서는 HVAC 시스템의 효율과 안정도에 결정적인 영향을 미치는 파열도와 저압을 제어하기 위해, 비선형성이 강하고 불확실하며 복잡한 시스템을 쉽게 제어할 수 있는 Fuzzy 제어기를 구성하여, 3대의 Expansion Valve 와 1대의 Compressor 에서 동시에 제어하는 Multi 제어기를 설계한다. 제안된 Fuzzy 제어기는 이산형 lookup_table 방식과 연속형 간략추론 방식을 사용하여 제어기를 설계하고, 유전자 알고리즘(GAs)을 이용하여 최적의 Fuzzy 제어기의 환산계수를 구한다. 그리고 시뮬레이션 결과를 통해 이산형 lookup_table 방식과 연속형 간략추론 방식의 각각의 제어기를 사용한 결과를 비교한다.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2004.11a
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• pp.43-48
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• 2004

The purpose of this study is to analyze the typological characteristics of super high-rise housings in Hong Kong. The results are as follows; 1) The Plan types of the residential building in Hong Kong are mostly tower types and they show lots of curves on the external resident blocks so each resident families can face maximum open air. 2)Household arrangements or resident families form are shown as symmetrical and systematic type of structures that centers around the core. 3)The core types are mostly central core types and a portion of central core is planned to place void and alight garden for improving the lighting and ventilating problems. 4)If we review our room arrangements, they are arranged from entrance kitchen, livingroom bedroom to bathroom to the end. Livingrooms and dinning rooms are normally formed together. 5)If external resident blocks are facing the open air, one of the surface is on view axis, kitchen or bathroom are symmetrically located on the other side which faces the units for the purpose of ventilating.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.12
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• pp.874-882
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• 2007

The effects of a guide fin blade on the flow characteristics in a ventilating axial fan were investigated experimentally. The guide fins were setup onto the pressure surface of the blade, and their effects on the flowrate were evaluated. Two types of the guide fin blade were designed. One is the stem fin blade, and the other is the radial fin blade. The stem fin is designed normal to the circumference of a circle, and the radial fin is designed along the circumference of a circle. The results from the guide fin blade fans are compared with that of the blade without guide fins. The position and the geometry of the radial fin setting up on the blade have an effect on the increase of flowrate with the minor sacrifice of rotational speed of the blades. The radial fin positioning at 0.84 times blade diameter shows highest performance in the flowrate. The increase of the blade weight resulting from applying the guide fins shows minor effect on the variation of rotational speed of the blades.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.18 no.12
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• pp.947-954
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• 2006

Building energy consumption according to the ventilation has been considered to be an important subject. The purpose of this study is to investigate the cooling and heating loads in a test space with a forced ventilating system. In the test space, on/off controlled air-conditioning and forced ventilating facility were operated between 8 : 30 to 21 : 00 during 4 days and some important data like temperatures and energy consumption were measured to obtain actual thermal loads. The simulation was carried out in a mode of temperature level control using a TRNSYS 15.3 with a precisely measured air change amount and performance data of air-conditioner. Heating load and cooling load including sensible and latent were compared between by experiment and by simulation. Both of thermal loads associated with ventilation show a close agreement within an engineering tolerance.