• 한국건축시공학회지
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• 제5권2호
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• pp.107-113
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• 2005

This study analyzes remaining repair rate and applied repair rate with the presentation of profit model for the purpose of pursuing maximization of added value through remodeling of apartment house. Objects of remodeling and item applying the whole replacement of functionality evaluation items include exterior of building (3 items maintaining the current conditions, 8 items requiring the whole replacement), water supply/sanitary/gas/ventilation facilities (6 items maintaining the current conditions, 6 items requiring the whole replacement, electric/fire fighting/elevator facilities (8 items maintaining the current conditions, 20 items requiring the whole replacement) and heating/water heater facilities (2 items requiring the whole replacement).

• Journal of Radiation Protection and Research
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• 제38권4호
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• pp.185-188
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• 2013

Heating method using electric heater was used to reduce water content in fingernail clippings. Authors found that low water content is helpful to measure EPR signal of fingernail sample with enhanced variability. Generally, natural dehydration happens in normal room condition at least one month and needs much time for using in experiment. So, artificial heating method is applied in this study for time savings. Fingernail samples were tested to find effect of water content to the EPR signal on microwave power levels for dosimetry. Low water content in fingernail reduced variability of EPR signal and makes it possible to measure accurate EPR signal. It also made it possible to measure constant movement of EPR signals on several microwave power levels. Although this method was difficult to apply directly in fingernail/EPR dosimetry, we, authors, believe that this heating method would be useful to differentiate MIS2 and RIS which are generally located at the same g-factor and almost impossible to be identified with each other.

• 한국태양에너지학회 논문집
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• 제31권5호
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• pp.41-46
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• 2011

In the present work, a new freeze protection method has been proposed for a natural circulation system of solar water heater. Though electrothermal wire is popularly used for the purpose, there are freezing troubles by wire cut-off and excessive electric power consumption. In the experimental device, hot water in a storage tank was circulated by a small pump and used to heat the outdoor pipes if the cold water pipe surface temperature falls lower than a set point. As a result, It was observed that there was no hot water waste while the solar water heating system operated without freeze and burst.

• 설비공학논문집
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• 제10권3호
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• pp.251-259
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• 1998

Environmental control facilities are used to simulate an environment or combination of environments under which many kinds of research and tests can be performed. The design of the control system to maintain desired environmental conditions is essential to proper operation of the facility. A simulation model of the facility has been developed by analyzing each component of the system thermodynamically with necessary properties and heat transfer relations. Using the system simulation model, the required characteristics of the control system has been investigated. PI controller is considered as the most probable controller for this kind of the facility, and electric heater power is shown as the Proper manipulated variable for temperature control.

• International Journal of Air-Conditioning and Refrigeration
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• 제8권1호
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• pp.62-72
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• 2000

Environmental control facilities are used to simulate an environment or combination of environments under which many kinds of research and tests can be performed. The design of the control system to maintain desired environmental conditions is essential to proper operation of the facility. A simulation model of the facility has been developed by analyzing each component of the system thermodynamically. with necessary properties and heat transfer relations. Using the system simulation model, the required characteristics of the control system has been investigated. PI controller is considered as the most probable controller for this kind of the facility, and electric heater power is shown as the proper manipulated variable for temperature control.

• 한국초전도ㆍ저온공학회논문지
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• 제14권4호
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• pp.46-49
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• 2012

The selection of the temperature sensor in the cryogenic system depends on the temperature range, shape and accuracy. The accuracy of the temperature sensor is essential to improve the reliability of experiment. We have developed the variable temperature cryostat using a two-stage cryocooler. In order to reduce heat load, thermal shield is installed at the first stage with MLI (Multiple layer insulation). We have also developed the sensor holder calibrating more than twenty sensors at the same time for saving time and money. The system can calibrate sensor at variable temperature by controlling electric heater. In this paper, we present design and fabrication of variable temperature cryostat and representative result of Cernox sensor calibration.

• 한국자동차공학회논문집
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• 제3권5호
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• pp.56-63
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• 1995

In this paper, the fuel atomization effect of a spark-ignition engine on the lean burn characteristics is studied. The fuel atomization is enhanced by heating the inside of the intake manifold with electric heater. Several operating parameters including cyclic variation are expressed against the air-fuel ratio from the experimental results. The fuel atomization gives much influence on the combustion stability. As the intake manifold is heated, the combustion duration decreased and the value of COV in the lean region as well as in the theoretical equivalence ratio became smaller than of not-heated.

• 한국안전학회지
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• 제18권3호
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• pp.101-108
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• 2003

Polymeric positive temperature coefficient(PTC) composites have been prepared by incorporating carbon black(CB) into high density polyethylene(HDPE), polyphenylene sulfide(PPS) and polybutylene terephthalate(PBT) matrices. A PTC effect was observed in the composite, caused by the large thermal expansion due to He consecutive melting of HDPE, PPS and PBT crystallites. This theory is based upon the premise that the PTC phenomenon is due to a critical separation distance between carbon particles in the polymer matrix at the higher temperature. The influence of PTC characteristics of the PPS/CB composite can be explained by DSC result. HDPE, one of prepared composition, exhibit the higher performance PTC behavior that decreaseing of negative temperature coefficient(NTC) effect and improved reproducibility by chemically crosslinking. Also, PBT/CB and PPS/CB composites exhibit the higher PTC peack temperature than HDPE/CB PTC composite, individually $200^{\circ}C$ and $230^{\circ}C$. These PTC composite put to good use in a number of safety application, such as self$.$controlled heater, over-current protectors, auto resettable switch, high temperature proctection sensor, etc.

• 한국분무공학회지
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• 제27권1호
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• pp.42-49
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• 2022

Flash boiling occurs in a couple of modern engineering systems and understanding its mechanism is important. In this experimental study, discharge coefficient of flash boiling spray from simple orifice nozzle was measured, and backlight imaging was acquired at injection pressure to 6.0 bar and temperature to 163℃ for the purpose. Pressurized water by pump was used for working fluid and was heated by electric heater and ejected through simple orifice nozzle diameter of 0.5 mm. High speed camera with long distance microscope was used for backlight imaging in two FoV having magnification of 3.3 and 0.64. The decrease of discharge coefficient according to degree of superheating and evolution of flash boiling spray imaged at various pressure and temperature were explained by the pressure field inside the injector.

• International Journal of Computer Science & Network Security
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• 제24권6호
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• pp.77-82
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• 2024

The Smart home energy consumption represents much of the total energy consumed in advanced countries. For this reason, the main objectif of this paper is to study the energy consumption profile by day for each home appliances: controllable appliances for example Washing machine, Tumble dryer and Air conditioning and uncontrollable appliances for example TV, PC, Lighting, Refrigerator and Electric heater. In this paper, we start with presentation of a smart home energy management systems. Next, we present the modeling and simulation of controllable appliances and uncontrollable appliances. Finally, concludes this paper with some prospects. The modeling and the simulation of a Smart home appliances is based on MATLAB/Simulink software.