• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1995.05a
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• pp.101-112
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• 1995

In order to improve the recovery efficiency of heavy water vapour from the atmosphere inside a reactor building, and to recover and upgrade the heavy water which escape, special treatments, such as reducing the ingress of light water vapour, are studied in the design of the CANDU reactor systems. This is considered in controlled method of the humidity over drawing fresh air through a desiccant dehumidifier which dries the air by absorption. Comparing with the moisture loads between summer and winter operations, the moisture removal rates are calculated. Those are proportional to the difference between the controlled space and the surrounding environment Installation of a new dehumidifier will be able to reduce the moisture loads from the cooling systems, improving overall system efficiency and saving operating costs.

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.54-58
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• 2011

According to the Fourth Assessment Report of the Inter governmental Panel on Climate Change(IPCC), climate change is already in progress around the world, and it is necessary to start mitigation and adaptation strategies for buildings in order to minimize adverse impacts. It is likely that the South Korea will experience milder winters and hotter and more extreme summers. Those changes will impact on building performance, particularly with regard to cooling and ventilation, with implications for the quality of the indoor environment, energy consumption and carbon emissions. This study generate weather data for future climate change for use in impacts studies using PRECIS (Providing REgional Climate for Impacts Studies). These scenarios and RCM (Regional Climate Model) are provided high-resolution climate-change predictions for a region generally consistent with the continental-scale climate changes predicted in the GCM (Global Climate Model).

• Journal of the Korean Solar Energy Society
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• v.27 no.4
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• pp.157-165
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• 2007

Typical meteorological data is fundamental to computer simulation introduced for environment-friendly architecture designs. Therefore, in order to improve accuracy of computer simulation, typical meteorological data should be established. By examining how to choose typical meteorological data, this study selected the optimized weight factor for TRY where weighting factor was not clearly set. As a result, the same weighting factor was applied to each climatic element and TRY data where the weight factor was applied could have the distribution very similar to measurement data. The weighting factor is considered to reflect geographical characteristics of Seoul and applied climatic elements.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.688-694
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• 2009

As a drive system for next generation train, we have been making research and development of a direct drive traction motor system without the conventional reduction gear. This traction motor is expected to have many advantages such as low noise, reduced maintenance, and energy saving. Due to the demand for high-output motors in the limited space between the wheels, open-ventilating traction motors with gear box have been widely used for many years. However, a conventional open-ventilating traction motor is necessary periodical disassembly to remove the accumulated dust from open-air ventilation. Reducing this burden, as well as increasing energy efficiency and reducing noise, would benefit the next generation of traction motors. To address these needs, KRRI have been developing a fully enclosed type direct drive motor(DDM) with high-efficiency permanent magnet for the next generation train.

• Nuclear Engineering and Technology
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• v.35 no.3
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• pp.226-233
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• 2003

The discharge characteristics of a prototype ion source was investigated, which was developed and upgraded for the NBI (Neutral Beam Injection) heating system of KSTAR (Korea Superconducting Tokamak Advanced Research). The ion source was designed for the arc discharge of magnetic bucket chamber with multi-pole cusp fields. The ion source was discharged by the emission-limited mode with the control of filament heating voltage. The maximum ion density was 4 times larger than the previous discharge controlled by a space-charge-limited mode with fully heated filament. The plasma (ion) density and arc current were proportional to the filament voltage, but the discharge efficiency was inversely proportional to the operating pressure of hydrogen gas. The maximum ion density and arc current were obtained with constant arc voltage ($80{\sim}100V$), as $8{\times}10^{11}cm^{-3}$ and 1200 A, respectively. The estimated maximum beam current was about 35 A, extracted by the accelerating voltage of 80kV.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05d
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• pp.259-266
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• 1996

This paper presents a geometrically non-linear formulation for the general curved beam element based on assumed strain fields and Timoshenko's beam theory. This general curved beam element is formulated from constant strain fields. And this element, designed in a local curvilinear coordinate system, is transformed into a global cartesian system in order to analyze effectively the general curved beam structures located arbitrarly in space. Numerical examples are presented to show the accuracy and efficiency of the present formulation. The results obtained from the present formulation are compared with those available in the literature and analysis by ANSYS.

• Solar Energy
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• v.12 no.3
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• pp.21-27
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• 1992

This study is presents model testing to evalute daylighting performance in Atrium Building. There are several methods fof the prediction of Daylighting level in a Atrium Building, But they are not sufficient to estimate intreior daylight level of each different hights onleaner Atrium Building. In this study provide with making the model to estimate the environmental effect for the daylight on leaner Atrium, measuring the model in 80 variable sky condition, building direction, interior length-width ratio through the variation of floor-hight and space ratio.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.457-457
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• 2013

Current-voltage (I-V) measurements of crystalline silicon solar cells was conducted under dark conditions with the temperature range of 260 K~350 K. Using the calculation method, we extracted the crucial factors of ideality factor (n) and activation energy (Ea) to investigate the carrier conducting path in the space charge region (SCR) and the quasi-neutral region (QNR). Values of n were decreased with increasing temperature in both SCR and QNR. We also conformed that the value of Ea of SCR was larger than that of QNR about 0.4 eV. The temperature dependence of n indicates that the carrier conducting path is dominated by carrier recombination-generation in the SCR region than in the QNR region.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.522-526
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• 2004

High cost of crude oil imposes a heavy burden on vehicle users. Thus, much efforts are given to the development of alternative energies in advanced countries as well as our country. Among them, fuel cell is emerged as the most promising one for transportation. There is no harmful emission with hydrogen energy of which sources are abundant on the earth. The use of both fuel cell with self-generating system and electromanetic guidance system will be able to make urban track rapid transit operate even in the city areas of very limited infrastructure space with flexibility and on time accessibility. The high efficiency is also expected with clean environment and easy riding for both the old and the handicapped.

• Electronics and Telecommunications Trends
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• v.32 no.6
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• pp.40-47
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• 2017

One of the main technical constraints of a conventional battery is the limited lifetime of electric energy supplied. With self-power generation using an internal radioisotope as an emitter of beta particles, and a PN-junction semiconductor as an absorber of the beta particles, a betavoltaic battery can provide electric energy to electric devices in a semi-permanent manner. Hence, a betavoltaic battery can be adopted as the solution to the power source issue of IoT devices placed in locations that people cannot easily access, such as in the deep sea, a desert, and space, and requiring a long operation time without an electrical charging. This paper covers the current trends in betavoltaic batteries including issues regarding their technology, application, and patents.