• KIEAE Journal
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• v.15 no.4
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• pp.5-11
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• 2015

Purpose: Recently, renewable energy system has been widely used to reduce the energy consumption and CO2 emission of building. A photovoltaic/thermal(PVT) system is a kind of efficient energy uses, which is combined with photovoltaic module and solar thermal collector. PVT system removes heat from PV module by through thermal fluid to raise the performance efficiency of the PV system. However, though PVT system has the merit of the improved efficiency in theoretical approach, there have been few performance analysis for PVT system using the dynamic energy simulation. In this study, in order to establish the optimum design method of this system, simulation was conducted by using individual system modules. Method: For the dynamic simulation, TRNSYS17 was used and local weather data was utilized. Furthermore, the system performance in various installation condition was calculated by case studies. Result: As a result, the amount of electric generation and heat production in each case was found by the simulation. The gap of system performance was also evident according to the installation condition.

• 한국태양에너지학회:학술대회논문집
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• 2012.03a
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• pp.255-259
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• 2012

BIPV/T (Building Intergrated PhotoVoltaic/Thermal) is combined system produces electricity and thermal energy. The heat from PV modules should be removed for better electrical performance, and can be converted into useful thermal energy. The test system is installed to top floor of the experimental house in the KEPCO Research Institute. The experimental performance is executed from 13th February to 13th March, 2012. The expected system's thermal performance is 1.9kWh under the horizontal solar radiation is $600W/m^2$ and the air flow in the system is $20CMH/m^2$.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.243-244
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• 2015

Power system has been improved during for a long time by customers demand. Power suppliers has researched the power system component for more electricity transmission. One of the research is apply the thermal conductors in new cable. The operational temperature of thermal conductors is higher than normal aluminum that thermal conductor is composed of aluminum, Zr(zirconium) and etc. Increase of operational temperature is growth of the transmission capability. Power suppliers was concerned about the increase of operation temperature by thermal conductors. Therefore, the thermal conductor has the possibility that expanded application in power system. In this paper analysed effect of thermal conductor in power distribution system.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.588-592
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• 2006

PV Thermal combined system produces the electricity and thermal energy which are needed for buildings. The system removes heat from PV module through air or liquid, so that its efficiency will be improved. The heat as the forms of hot air or hot water can be utilized for building use, like space heating and hot water. This paper describes the concept of PV Thermal combined system and its research and development trend at local and international levels. This materials can be used as a fundamental study source about PV Thermal combined system to apply fur building space heating.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.1
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• pp.117-124
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• 2003

Thermal design fur satellite propulsion system has been performed. Overall design requirements and the constitution for propulsion system is described. To meet the thermal design requirements, both a primary and a redundant heater circuit, each with two thermostats placed in series, will protect each hydrazine-wetted components, even if one heater circuit fails to operate. Heater power is turned off if any one of these thermostats is opened at its higher setpoint. Thus, even if one thermostat is failed closed, the second thermostat will turn off the heater. All such components shall be insulated with MLI. Propulsion heater sizing based on the constant worst cold case condition is conducted through thermal analysis. All heaters selected fur propulsion components operate to prevent propellant freezing satisfying the thermal requirements for the propulsion subsystem over the worst case average voltage, i.e. 25 volts.

• Transactions of the Korean hydrogen and new energy society
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• v.18 no.3
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• pp.292-300
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• 2007

A dynamic system model of a proton exchange membrane fuel cell(PEMFC) has been developed. The PEMFC of this study has large active area with water cooling in order to simulate the performance of the commercially viable PEMFC system for the transportation. A PEMFC stack model is a transient thermal model which is respond to the dynamic change of the coolant temperature and the flow rate. The dynamic cooling system model has been developed to determine the coolant flow rate and the coolant temperature. Prior to the system level study, thermal management criteria have been set up and brought to the control command of the cooling system. Since the system model is designed to evaluate the effect of thermal management on the system performance, it is attempted to determine the proper control algorithm of the cooling system so that the PEMFC system is working on the thermal management criteria. As a result of simulation, feedback controlled cooling system consumes less power and produce more power comparing with that of conventionally controlled cooling system.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1269-1271
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• 2009

We had proposed fast thermal stress estimation methodology for the components on system board when the system is stationary within specific ambient air temperature. Now, we will propose one efficient thermal stress estimation methodology, block adaptive filtering methodology, for the FPD electronic system board which is enclosed by mechanical cover.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.12
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• pp.647-653
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• 2013

TABS (Thermally Activated Building System) has recently applied by huge commercial buildings, airports, and convention centers in Europe. TABS provides night-time thermal storage by heating or cooling. The embedded water-based heating and cooling system uses the high thermal inertia of concrete in the building construction, in which a heating or cooling pipe is embedded. The aim of this study is to analyze the thermal storage and thermal output of TABS applied with PCM (Phase Change Material). To achieve this, prototypes of TABS and the thermal properties of various PCMs were investigated. By using the simulation program Physibel Voltra 6.0 W, the thermal storage and thermal output were evaluated according to a heating and cooling operation schedule.

• 한국신재생에너지학회:학술대회논문집
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• 2010.06a
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• pp.197.2-197.2
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• 2010

The study on the operation characteristics of solar space and water heating system with ground source heat pump (GSHP) as a back-up device was carried out. This system, called solar thermal and geothermal hybrid system (ST/G), was installed at Zero Energy Solar House II (KIER ZeSH-II) in Korea Institute of Energy Research. This ST/G hybrid system was developed to supply all thermal load in a house by renewable energy. The purpose of this study is to find out that this system is optimized and operated normally for the heating load of ZeSH-II. Experiment was continued for seven months, from October to April. The analysis was conducted as followings ; - the contribution of solar thermal system. - the appropriateness of GSHP as a back-up device. - the performance of solar thermal and ground source heat pump system respectively. - the adaptation of thermal peak load - the operation characteristics of hybrid system under different weather conditions. Finally the complementary measures for the system simplification was referred for the commercialization of this hybrid system.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.9
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• pp.1359-1367
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• 2001

Improvement of machine tool accuracy is an essential part of quality control in manufacturing process. Among of all the errors of a particular machine tool, the thermal errors of the spindle have a notably significant effect on machining accuracy and have a direct influence upon both the surface finish and geometric shape of the finished workpiece. Therefore, this paper proposed new measurement method for thermal errors of the spindle in machine tools. The thermal errors are measured by a ball bar system instead of capacitance sensor system. The novel measurement method using ball bar system is more efficient, easier to use than conventional measurement system. And also the ball bar system is possible to measure both geometric errors and thermal errors at the same time.