• Journal of environmental and Sanitary engineering
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• v.17 no.3
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• pp.46-51
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• 2002

This study was performed to treat a sewage at the upper stream of dam using modified sequencing batch reactor, During the operating period, average $COD_{cr}$, removal efficiency was about 85% but average T-N and ${PO_4}^{3-}-P$ removal efficiencies were 43% and 30% respectively. Because the organic matter was very low compared with nitrogen and phosphorous in influent($BOD_{5}/{NH_4}^{+}-N{\;}={\;}2,{\;}BOD_{5}/{PO_4}^{3-}-P{\;}={\;}15.6$), nitrogen and phosphorus removal efficiency was relatively low. Average nitrogen removal efficiency was 50 % at $10^{\circ}C$ or above and it was 36 % at $10^{\circ}C$ or below. As reactor was located in outdoor without any thermostat, temperature decreased at least $2.4^{\circ}C$ in the winter season. Therefore, if we would apply this modified sequencing batch reactor to sewage which concentration of organic matter was very low compared with nitrogen and phosphorous, we have to addition of external carbon and installation of any thermostat.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.6 no.2
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• pp.78-92
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• 1994

Thermal performance of pipe network of continuous heating system controlled by thermostat and flow control valve was simulated in consideration of radiation heat transfer and solved by linear analysis method. Thermal performance of real apartment building with radiant floor heating system was simulated by equivalence heat resistance-capacity method. This method enables to simulate the unsteady variation of temperature or each element of building. Heat transfer characteristics of each element were also investigated.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.3
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• pp.35-41
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• 2001

In recent applications, map controlled thermostat has been adapted to optimize engine cooling system and vehicle cooling system. First of all, this strategy is focused on improving fuel consumption rate and reducing emissions, especially unburned hydrocarbon. The object can be obtained through controlling engine metal temperature by varying engine coolant temperature with engine load and speed. To achieve this goal, it is necessary to understand the characteristics of engine metal temperature and heat rejection rate to coolant. From the results of tested engines, it is obvious that fuel consumption rate has more dominant effect on engine metal temperatures than the corresponding engine power does. Also, Re-Nu relation which shows heat rejection rate to coolant in function of air-fuel mixture and engine specifications has been studied. Also, the empirical Re-Nu relation at full loaded engine was developed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.655-656
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• 2013

• Korean Journal of Soil Science and Fertilizer
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• v.47 no.6
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• pp.571-578
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• 2014

The garlic cultivation area is moved by change of grown environment due to global warming. It is important to predict changes in cultivation area, quantity and quality of each crop. This study was carried out to estimate the yield and response of garlic growth by the rapid temperature changes in the greenhouse with thermostat control system. Seedlings of Namdo garlic were planted on September 27, 2012 and harvested on May 30, 2013. The used treatments for a rapid temperature change in March-April-May were T0 (control): $6.0-10.4-17.2^{\circ}C$, T1: $6.0-5.4(-5)-17.2^{\circ}C$, T2: $6.0-10.4-22.2(+5)^{\circ}C$ and T3: $6.0-5.4(-5)-22.2(+5)^{\circ}C$. Total dried weight per plant of garlic significantly increased by 5.0% for T2, but T1 and T3 decreased by 12.5 and 4.6%, respectively, compared to T0. Total yields of bulb within the temperature change as T2 and T0 increased significantly (p<0.05), as compared to T1. Decreasing temperature significantly (p<0.05) reduced plant height, SPAD reading, crude protein and fiber contents etc., as compared to T0 and T2. ABA contents gradually increased with time but IAA content rapidly decreased. Conclusively, growth and yield of garlic were more affected by decreased temperature than increased temperature at bulb development stage.

• Fire Science and Engineering
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• v.20 no.3 s.63
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• pp.113-117
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• 2006

This study presents analysis of fire hazard of electrical heating pad. In order to analyze fire hazard fire experimental and flammability experiment is conducted. The fire experiment is conducted to simulate normal condition and abnormal condition such as breakdown of thermostat. Vertical burning test(UL 94) is conducted for the fire retardant experiment. Kinds of electric heating pad used for experiment are electric mat, fabric pad, vinyl pad. The results show that fire hazard is high in case of breakdown of thermostat with the rating voltage supply. And Material of electric heating pad has not fire retardant performance.

• Journal of the Korea Safety Management & Science
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• v.26 no.1
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• pp.31-38
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• 2024

In this paper, as there are many cases of fires occurring due to the failure or inoperability of the thermostat of electronic products, the purpose is to test and analyze the risks and probabilities through fire cases and reproduction experiments, and suggest countermeasures. Among electronic products, water purifiers are composed of a refrigerant system with a compressor to make cold water, a heating device to make hot water, and an electric device used as an energy source. Due to the nature of the water purifier manufacturing, these devices are subject to a lot of moisture and dust. etc. exist in large quantities and use electrical energy, so there is a possibility of fire due to short circuit in the wire, electrical abnormal overheating (tracking phenomenon) in the thermostat, electronic board, starting relay, etc., and overheating of the heating device (Band Heater). there is. Therefore, in order to prevent fires from these devices, a system to remove foreign substances inside the water purifier is necessary, the use of heat-resistant (fire-resistant) wires for electrical devices is essential, and the use of non-combustible materials (semi-combustible materials) for each part is necessary to prevent fire. The risk must be eliminated through prevention and combustion expansion prevention devices.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2011.11a
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• pp.44-47
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• 2011

본 연구는 냉온수기에 사용되는 서모스탯을 예를 들어 전기기기에 온도컨트롤로 많이 사용되고 있는 서모스탯의 트래킹 화재 위험성 및 원인 분석을 위한 감정 기법에 관한 연구로서 트래킹을 발생시킬 수 있는 환경적 요인 및 오염액의 전도도 측정과 화재 후 트래킹에 의한 화재 원인 규명을 위한 감식 감정 기법에 관한 연구를 수행하여 화재 예방대책의 기초자료를 제시 하고자 한다.

• Proceedings of the KIEE Conference
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• 2003.07d
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• pp.2209-2211
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• 2003

마이크로제어기의 성능과 기능이 강화되는 반면에, 가격은 점점 낮아져, 다양한 논리기능의 구현이 가능해져, 특히 퍼지논리 제어기의 구현이 매우 보편화되고 있다. 이에 따라 종래의 On-Off 온도제어기로 구현이 어려웠던 다양한 제어기능을 구현함으로써 보다 쾌적하고 전기료를 절약한 절전형 온도제어기의 출현이 가능하게 되었다. 본 논문에서는 8비트형 마이크로 콘트롤러를 사용한 퍼지논리 제어기의 실용적인 설계를 fyzzyTECH의 상용화된 도구를 사용하여 구현하였다. 이 방법은 종래의 방법에 비해 성능, 가격 및 에너지 절약측면에서 매우 우수한 성능은 발휘하였다.

• Transactions of the Korean Society of Automotive Engineers
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• v.25 no.3
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• pp.297-308
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• 2017

One of the major engine thermal management system(TMS) strategies for improving fuel economy is to operate the engine in high temperatures. Therefore, this work performed a numerical and experimental study to examine the effect of several different STOs(Starting Temperature of Opening) of wax-thermostat, ranging from $85^{\circ}C$ to $105^{\circ}C$, of gasoline engine on fuel economy and emission characteristics. In this study, a gasoline car equipped with waxthermostat was tested and simulated under FTP-75 and HWFET mode. CRUISE $M^{TM}$ was used to simulate vehicle dynamics, transient engine performance and TMS. The test results showed fuel savings for both drive cycles due to higher STO of $100^{\circ}C$, which is slightly worse than that of $90^{\circ}C$ and amounts between 0.34 and 0.475 %. These controversial results are attributed to experimental errors and uncertainty. The computational results for three STOs, $85^{\circ}C$, $95^{\circ}C$ and $105^{\circ}C$, showed that fuel savings attributed to the application of higher STOs of $95^{\circ}C$ and $105^{\circ}C$ are relatively small and range from 0.306 to 0.363 %. It is also found that the amount of HC and CO emissions from the tailpipe tends to decrease with higher engine coolant temperature because of faster catalyst light-off and improved combustion.