• 한국태양에너지학회:학술대회논문집
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• 2011.11a
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• pp.115-123
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• 2011

Because buildings recently built have been highly insulated and highly airtight, it is impossible to emit toxic substances from interior finishing materials only by natural ventilation. Therefore, they cause indoor air pollution and it may threaten the user"s health such as atopic dermatitis, bronchial asthma and (allergic) rhinitis. Domestically, users spend indoors 80 percent of their time of a day. With the increased interest in indoor air quality, the introduction of forced ventilation system for new-built apartment buildings has been legislated. However, toxic substances from indoor are mostly below there commended standard approximately 23 months later. Thus, this study has assumed the status of the apartment buildings 23 months later through a simulation, regarded $CO_2$ as an exclusive indoor air pollution source. In the process of effectively eliminating the $CO_2$, this study has also been conducted on an operating plan that can provide superior performance from the energy side.

• 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.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.4 s.235
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• pp.469-476
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• 2005

Numerical modeling has been carried out to investigate the two-dimensional air flow in automobile interior with a forced exhaust close to main air inlet for typical ventilation modes. The characteristics such as streamlines and temperature fields in the passenger compartment room with the forced exhaust are analyzed with comparison of the cases without a forced exhaust. The simulation results show that air flow on the floor near the front seat is increased with the forced exhaust for all ventilation modes. Flow recirculation in the cabin is most active in mode 2 with a vertical suction inlet in comparison with other two modes. In particular, less time is taken for air temperature to reach the inlet temperature due to the forced exhaust for the ventilation modes. Finally, it could be predicted that ventilating air flow is much improved with the forced exhaust in the interior Modeling results in this study can be applied to the optimal design of automobile interior fur air ventilation system.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.02a
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• pp.171-176
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• 2003

육계사의 대형화에 따른 최적환경조성의 중요성이 대두되고 있어서, 이에 따른 적합한 시설환경이 더욱 요구되고 있으나 적정환기가 이루어지지 않아 육계의 생산성 향상에 어려움이 많이 있다. 국내 대형육계사내 최적환경제어를 위한 주요환경변수의 기초자료가 매우 부족한 실정이다. 최 등(1999)은 육계사의 대표적인 여러 계사구조에서 온도, 습도, 유해가스농도 및 육계의 체중, SDS 발생율 및 폐사율, 도체이상 발생율 등을 조사하였다 황보 등(2002)은 3(W)$\times$5(L)$\times$3(H)의 무창계사에서 환경요소 중에 온도, 습도, 공기유속을 분석하여 환경효율을 조사하였다. 대부분의 관련연구들의 자료로는 계사내 환경 균일성, 적정성, 안정성 등을 효과적으로 분석하는 것이 어려웠다. (중략)

• Proceedings of the Korea Society of Poultry Science Conference
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• 2002.11a
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• pp.108-109
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• 2002

The study was carried out to iind out the suitable ventilation system of the broiler house in winter season in Korea. Ammonia (NH$_3$-N) gas concentration (4.2ppm) of the system of pipe air inlet-forced chimney outlet was lower than that of the system of side wall inlet. The growth performance of broilers in the house equiped with pipe air inlet-chimney exhaust was higher than that of other ventilation systmes in which the average daily gain, feed efficiency and heat cost per head in the system of pipe air inlet-forced chimney excretion were 45.6g, 1.71 and 35.4 won per head, respectively. When the lengths of pipe air inlets were compared, the wind speed from the 4 meter-inlet was highest. The temperature of the broiler house equipped with the pipe air inlet system was higher (5.9 ∼ 7.7$^{\circ}C$) than that of the curtains in side wall Inlet system, in which the pipe air inlet system expects the lower heat cost.

• Journal of the Korea Institute of Military Science and Technology
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• v.3 no.2
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• pp.81-87
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• 2000

This paper presents an application of forced oscillation technique to measure pitch dynamic stability derivatives of a missile model in the low speed wind tunnel. The missile model is oscillated by D.C. electric servomotor with constant amplitudes and frequencies. Phase shift is determined as the difference of peak values between input and output signals from the dynamic stability balance installed at the center of gravity of the model. Stability derivatives were calculated by using phase shifts, amplitudes, forcing moments and input frequencies. Test results show the proper usage of the force oscillation technique with good damping effects.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.3
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• pp.183-192
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• 2005

Natural ventilation in radioactive waste repositories is considered to be less efficient than mechanically forced ventilation for the repository working environment and hygiene & safety of the public at large, for example, controlling the exposure of airborne radioactive particulate matter. It is, however, considered to play an important role and may be fairly efficient for maintaining environmental conditions of the repository over the duration of its lifetime, for example, moisture content and radon (Rn) gas elimination in repository. This paper describes the feasibility of using natural ventilation which can be generated in the repository itself, depending on the conditions of the natural environment during the periods of repository construction and operation. Evidences from natural cave analogues, actual measurements of natural ventilation pressures in mountain traffic tunnels with vertical shafts, and calculations of airflow rates with given natural ventilation pressures indicate possible benefits from passive ventilation for the prospective Korean radioactive waste repository. Natural ventilation may provide engineers with a cost-efficient method for heat and moisture transfer, and radon (Rn) gas elimination in a radioactive waste repository. The overall thermal performance of the repository may be improved. The dry-out period may be extended, and the seepage flux likely would be decreased.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.7
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• pp.4047-4051
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• 2014

Modern apartment houses are constructed to be relatively airtight with a high heat insulation system to increase the energy efficiency. Such a system has a range of deleterious effects due to the insufficient ventilation. In this study, the ondol system, which is used as a heat source typical of winter in Korea, was set as the default system to evaluate the indoor heat environment according to the ventilation method, the factors of energy reduction by the ventilation system was analyzed. The experimental apparatus was used to simulate the ambient conditions for a certain constant temperature and humidity chamber. The experimental results showed that the supply water temperature higher air volume decreases with increasing supply air temperature in the following order: floor supply/exhaust > total heat exchange supply/exhaust > forced supply/exhaust. Through this study, the applicability of various ventilations could be examined.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.33 no.6
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• pp.32-36
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• 2004

주택의 공기질 환경에 대하여 사회적 이슈가 된 새집증후군에 대한 언론매체의 집중적 보도와 실내 공기질이 인체에 미치는 영향에 대한 연구보고서의 잇따른 발표에 따라 실내 공기 질에 대한 관심이 점점 더 고조되고 있는 시점에 환경부의 실내공기질 관리법에 의해 2004년 5월부터 신축되는 공동주택의 경우 포름알테히드와 VOCs등 새집에서 발생되는 유해 물질을 입주 전 측정하여 공고하여야 한다는 법이 제정이 되어있다. 따라서 각 건설사 및 관련 업계에서는 실내의공기질을 개선하기 위한 다양한 방법을 연구하고 있으며 일차적으로 유해오염물질이 발생되지 않는 건축자재를 사용하는 근본적인 오염원인을 제거하는 source control를 선행을 하고 2차적으로 거주자가 주거생활을 하면서 발생시키는 오염물질인 $CO_2$및 분진 냄새 등은 강제환기를 통해서 개선시키는 방법을 채택하여 실내공기 질을 개선하고자 노력하고 있다. (중략)

• Journal of Bio-Environment Control
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• v.32 no.3
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• pp.197-204
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• 2023

Heat stress causes a decrease in immunity and disease occurrence in livestock, increasing mortality and impairing productivity. In particular, chickens are very vulnerable to high temperatures compared to other livestock species because their entire body is covered with feathers and sweat glands are not developed. Currently, air conditioning systems are essential in broiler houses to prevent high-air temperature damage to broilers, but conventional cooling facilities are greatly affected by the external environment, so there are limits to their use. In this study, to propose a cooling method, thermal insulation paint and a heat pump were apply in the broiler houses to evaluate the temperature reduction effect. The heat pump experiment was to analyze the cooling effect according to the change in ventilation rate and propose an appropriate. As a result of the experiment, the heat-insulating paint reduced the temperature of the broiler houses by maximum 1-2℃, and in the broiler houses where the heat pump was operated, the temperature decrease was the largest when the ventilation rate was the lowest. When the air temperature in the house is similar to or lower than the outside air temperature, it is considered to be most effective to use a heat pump while maintaining only the minimum ventilation rate.