• Journal of Bio-Environment Control
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• v.10 no.2
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• pp.80-87
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• 2001

This study was conducted to provide basic data for the design of shading facility of greenhouse. The proper distance between external shading screen and roof surface, transmissivity of shading materials, and shading effects of external and internal shadings were analyzed. About a distance of 10 cm between inclined external shading screen and roof surface was enough to guarantee the external shading effect in the greenhouse without roof vent. The inside temperature of greenhouse installed with 85% internal shading screen was lower the maximum of 4$^{\circ}C$ and mean of 2$^{\circ}C$ than that with 55% internal shading screen in both natural ventilation and no ventilation condition. The difference of soil temperature between shading and no shading greenhouse was great, but the difference by shading rate or shading method was small. The performance of external shading for controlling inside temperature down was superior to that of the internal shading. The externally inclined shading screen parallel to the roof surface of greenhouse was more effective than the externally horizontal shading screen in controlling inside temperature of greenhouse without roof vent.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.10 no.3
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• pp.463-469
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• 2009

We performed the experimental study on the control of suspended dust in a cement packaging process for various ventilation systems. To effectively remove the dust generated in the cement packaging process, three different kinds of ventilation system, such as local exhaust ventilation, electrostatic scrubber, and local air supply system, were adopted. Dust concentrations in the packaging process were measured with the variation of the airflow rate of the ventilation systems and then their ventilation performance were evaluated. From the results, we knew that the ventilation performance was the best when the local exhaust ventilation and the electrostatic scrubber were simultaneously operated in the packaging process. In the electrostatic scrubber system, the effect of the airflow rate on the indoor dust removal efficiency was negligible so hat he system ust be operated at $2,700m^3/h$ for saving power consumption.

• Journal of Internet Computing and Services
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• v.21 no.6
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• pp.95-104
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• 2020

In this paper, we propose the real time indoor air quality monitoring and controlling platform on cloud using IoT sensor data such as PM10, PM2.5, CO2, VOCs, temperature, and humidity which has direct or indirect impact to indoor air quality. The system is connected to air ventilator to manage and optimize the indoor air quality. The proposed system has three main parts; First, IoT data collection service to measure, and collect indoor air quality in real time from IoT sensor network, Second, Big data processing pipeline to process and store the collected data on cloud platform and Finally, Big data analysis and visualization service to give real time insight of indoor air quality on mobile and web application. For the implication of the proposed system, IoT sensor kits are installed on three different public day care center where the indoor pollution can cause serious impact to the health and education of growing kids. Analyzed results are visualized on mobile and web application. The impact of ventilation system to indoor air quality is tested statistically and the result shows the proper optimization of indoor air quality.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.123-134
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• 2002

An experiment was conducted to establish the most suitable ventilation system for the enclosed nursery pig house in Korea, comparing four different ventilation systems ; i) air enters through perforated ceiling and exhausts through chimney (NA), ii) air enters through perforated ceiling and exhausts through side walls (NB), iii) air enters through perforated ducts and exhausts through side walls (NC) and iv) air enters through perforated ducts and exhausts through chimney(ND). The experiment was carried out during winter and summer separately. The experimental pigs were weaned at fourteen days old in winter (December-February) and at twenty one days old in summer (June-August). The main results of the experiment are as follows : A preliminary experiment showed that in the NC system during summer, air can reach all the pig rooms in the house and the air flow rates of the upper, middle (1.2 m height of the room) and low (at the height of pig stature) parts of the room were measured at 7.0-8.08, over 0.5 and over 0.2 m/s, respectively, which flow rates were much higher(p$<$0.05) than those in other system. At the minimum ventilation efficiency during winter, air flow rates of upper, middle and low parts of the room equipped with the NC system were detected at over 1, less than 0.5 and around 0.07 m/s, respectively. It is concluded that the separated ventilation system air-entering through ducts is the most suitable for the ventilation system of the enclosed nursery pig house and the exhausting system through side walls is more efficient for ventilation than the system through roof. Furthermore, to sustain proper temperature and reduce energy waste as well as heat consumption, a future research should be carried out to develop the environmental control system in relation to developing a heat regulator.

• Journal of Animal Environmental Science
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• v.18 no.1
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• pp.1-8
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• 2012

The study was conducted to investigate the effects of climate on indoor environment of a swine house with natural. This study was tested in the beef swine stall at Young-in, Kyung-ki do. The test was experimented for the effect of interior environment by the outdoor environment and the interior-pan. The results are as follows. 1. In test 1 ($T_{out}$ : $25.7^{\circ}C$, without fan), an indoor air flow pattern was showed that entered from sidewall winch-curtain to went out of a indoor by the ridge winch-curtain. And the velocity of a section of the center was measured two times as large as the velocity of the floor. It is the acceleration of the velocity by thermal buoyancy. And, the entered air was rapidly dissipated by flow energy. So that in the swain livestock with sidewall winch-curtain is effected by thermal buoyancy. And the air temperature of the indoor was distributed more higher as compared with the outdoor temperature. This result is caused by the sensible heat from swine and the ventilation is restricted. 2. In test 2 (($T_{out}$ : $25.7^{\circ}C$, with fan), the velocity of a section of the center was measured more higher as compared with the test 1. And the variance of air velocity was distributed higher as compared with the test 1. This result is showed dead region of air flow with a fan operation. And, the variance of gas density was distributed lower as compared with the test 1.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.3
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• pp.191-198
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• 2015

Noise propagated through the ventilation openings of enclosures is actively controlled using an FIR filter. The enclosures considered in this paper are used for isolating noise due to machinery. This method is of limited use because of the ventilation openings through which most of noise is propagated. Feedforward control strategy is incorporated to minimize the acoustic power propagated through the openings. For the real-time implementation, although it is numerical study, the controller is implemented using an FIR filter. The acoustic transfer functions of the pressure on the openings of the enclosure to the primary source and to the secondary source are numerically calculated using the boundary element method. The performance analysis of the active control is conducted with the time-domain simulation using Matlab Simulink.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.4
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• pp.753-758
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• 2020

In this paper, we intend to develop a control system that can apply the developed vertical stirring heater to the facility house and control the other facilities (circulating fan, ventilation fan, window using a switching motor, ceiling, and dehumidification). Through this, it is intended to increase the cultivation efficiency of crops and improve storage environment of crops held by non-heated storage or storage warehouses to increase the storage period and freshness. In addition, ICT monitoring technology is added to enable users to easily solve problems when there is a problem due to changes in the cultivation and storage environment with Real Time Control (RTC).

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.17 no.3
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• pp.25-31
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• 2003

In this paper, proposed is a control system for a galvanometer which is widely used fer laser display, laser processing and marking systems. The galvanometer with mirror is modeled as a second-order dynamic system Based on frequency responses and time domain responses of the developed model, a conventional PID controller is designed And it is implemented using a DSP(TMS320C32) chip with precision A/D and D/A converters. Through frequency response and experimental results, it is convinced that the proposed control system works well in real environment. Furthermore it is very easy to be connected to any PC because of USB communication port, and the cost of the marking system can be lowered very much because the DSP do the all the jobs for generating font motion as well as controlling the galvanometer.

• Proceedings of the Korean Society of Computer Information Conference
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• 2019.07a
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• pp.241-242
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• 2019

4차 산업 혁명에 맞춰 빠르게 발전하고 1990년대부터 등장하기 시작했던 '인텔리전트 빌딩'이 다시 주목을 받고 있다. 센서와 컴퓨터가 내장된 사물들이 인터넷으로 연결되어 각종 서비스를 제공하여 환경을 변화시키고 삶이 편해지고 있다. 그럼에도 불구하고 편리함을 추구하는 기존 기술 들은 대기업들이 주를 이루어 관리를 하게 되고 있고 유지 보수비용이 많이 들어 스마트 기기에 능숙하지 않은 부분도 있어 본 논문은 보다 기존의 IOT 기술보다 유지 보수비용의 절감과 손쉬운 접근방식을 제공한다. 본 논문인 '구글 어시스턴트를 이용한 스마트 홈 제어'는 집 전체를 제어하여 조명, 냉난방, 환기 등을 조절하고 무단 침입자를 감지하며 경고음을 알려주는 것이다. 예를 들어 집 주인이 외출을 하였는데 가스렌지의 불을 안 끄고 나왔거나 조명을 안 끄고 나왔는데 집을 다시 들어가기 어려운 상황일 때 핸드폰으로 버튼 하나만 누르면 제어가 된다. 본 논문의 목적은 집안의 화재나 전기 요금절감을 위하고 편리한 삶을 추구하고자 개발 되었다.

• Tunnel and Underground Space
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• v.15 no.1 s.54
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• pp.55-60
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• 2005

In this study, the 1/20 reduced-scale experiments using Froude scaling were conducted to investigate the effect of longitudinal ventilation on the variation of burning rate in tunnel fires. The methanol square pool fires with heat release rate ranging from 3.57 kW to 10.95 kW were used. The burning rate of fuel was obtained by measured mass using load cell and temperature distribution were measured by K-type theomocouples in order to investigate smoke movement. The wind tunnel was connected with one side of the tested tunnel, and logitudinal ventilation velocity in the tested tunnel was controlled by power of the wind tunnel. In methanol fire case, the increase in ventilation velocity decreased the turning rate due to the direct cooling of fire plume. For the same dimensionless velocity(V), homing rate decreased as the size of pool fire increased.