• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
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• pp.621-625
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• 2008

There are nine hot spring wells at Icheon hot spring area, hot springs are pumped by submersible motor. Drilling depths of hot spring wells is about 166-294 m, piezometric heads of hot springs is about 50 m below the surface. The geothermal gradient of SB-2 is about $64.00^{\circ}C$/km from the surface to depth within 300 m which is the highest value, that of SB-1 is about $45^{\circ}C$/km which is the lowest value. In addition, the average geothermal gradient of the region is calculated at approximately $54.28^{\circ}C$/km. However, it is analysed that this area has highly irregular temperature distribution because the groundwater penetrated to the depth of 720 m through the fracture rise to the surface according to the results of the data after drilling well to the depth of 996 m.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.565-568
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• 2009

Most of the historic hot springs are artesian wells in Korea. However, many boreholes have been drilled due to the shortage of hot water, and hot water is now being pumped by submersible pump installed at most of hot spring areas. The distribution of boreholes are expected to be related to the geological structure, and the study was carried out to interpret the relationship between two factors. The distributional maps of boreholes were made and the geological structures were interpreted at eight hot spring areas. Some distributions of boreholes have no special direction, and these are not related to the geological structure at Dogo, Suanbo, and Deoksan. The others are consistent with the direction of the geological structure at Goseong, Onyang, Sokcho, Yuseong, and Bugok.

• The Transactions of the Korean Institute of Electrical Engineers C
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• 제50권8호
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• pp.419-422
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• 2001

This paper presents the principle and fabrication of a novel micro mass spectrometer and emission test of hot electron for ionization. A micro mass spectrometer consists of a micro ion source and a micro ion separator. The micro ion source consists of a hot filament and grid electrodes. Electrons emitted from a hot filament are to ionize some sample molecules. The ions are accelerated to an ion detector by an electric field. Mass can be analyzed by using the time of fight depending on the mass-to-charge ratio. The current of hot electron emission from the hot filament is measured for various input voltages.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 춘계학술발표대회 논문집
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• pp.241-246
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• 2008

In this paper, we analyze the I-V curve and hot-spot phenomenon caused by solar cells' serial and parallel connected circuit. The mis-match loss of parallel interconnection with low Isc string decrease lower than serially interconnected one and temperature caused by hot-spot does. Also, mis-match loss of parallel interconnection with low Voc string increase more than serially interconnected one. The string having low Voc happened hot-spot phenomenon when open circuit. The bad solar cell in string gives revere bias to good solar cell and make hot-spot phenomenon. If we consider the mis-match loss, when designing PV module and array. the efficiency of PV system might increase.

• International Journal of Concrete Structures and Materials
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• 제7권2호
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• pp.165-174
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• 2013

Portland cement concrete exposed to high temperatures during mixing, transporting, casting, finishing, and curing can develop undesirable characteristics. Applicable requirements for such the hot weather concrete differ from country to country and government agencies. The current study is an attempt at evaluating the hardened properties of the concrete exposed to hot weather in fresh state. First of all, this study reviews the current state of understanding and practice for hot weather concrete placement in US and then roadway sites with suspected hot weather concrete problems were investigated. Core samples were obtained from the field locations and were analyzed by standard resonance frequency analysis and the boil test. Based on the results, there does not appear to be systematic evidence of frequent cracking problems related to high temperature placement. Thus, the suspicious deteriorations which are referable to hot weather concreting would be due to other factors.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 한국공작기계학회 2004년도 추계학술대회 논문집
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• pp.156-161
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• 2004

The application of solar energy, in the field of alternative energy, was on the increase tendency. In the case of advanced nations, through continuous R&D, solar hot water heater with high efficiency has been used for the house and the industrial process on business, advanced nations were reached up the experimental stage of solar generation system. But, the actual circumstance of the domestic has been not accomplished the popularization of solar hot water heater and the settlement of it which is the fundamental stage of the solar energy usage. This trouble, the domestic was flooded with small enterprise for producing solar hot water heater, was caused by the popularization and the production without verification of performance. To supply the monitoring program for evaluating solar hot water heater, this research was purpose to improve the technical development of the enterprise for producing solar-heat hot-water-boiler and served as an aid for the enlargement and the popularization on solar energy.

• Journal of the Korean Society of Manufacturing Process Engineers
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• 제17권4호
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• pp.83-90
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• 2018

In this research, we developed a process design hot-forging technology that precisely forms an inner race. The inner race transmits power to a one-way clutch of an automatic transmission and minimizes the CNC machining allowance. For a multi-stage hollow shape (inner race), we proposed several shapes of blocker and finisher for the precision hot-forging process and analyzed the forging process using DEFORM. The hot-forging process was optimized for several parameters, such as metal flow pattern, forging defect, and forming load. Blockers and finisher dies in the hot-forging process were designed to select optimal shapes from finite element analysis, and experiments were conducted to optimize the hot-forging process.

• Transactions of Materials Processing
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• 제24권1호
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• pp.20-27
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• 2015

Hot tensile tests were conducted at different temperatures ranging from $20^{\circ}C$ to $550^{\circ}C$ to evaluate the mechanical properties of Al5052 seamless tubes. Such tubes can provide the technological foundation for complex forming using hot air bulging. Hot air bulging is one of the recently developed hydroforming techniques and it has some limitations in terms of cycle times. The benefits of hot air bulging are weight and cost savings through part consolidation and reduced post-forming processes such as welding and piercing. In order to extend the forming limits of Al lightweight material hot air bulging was investigated. A heated tube was placed in a heated die and sealed at the ends by sealing cylinders. The heated tube was subsequently expanded against the die cavity wall by internal pressure using air medium. The results of the current study show that axial feeding speed and air pressure have an effect on the formability of Al tubes during air bulging at elevated temperatures.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• 제11권6호
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• pp.758-765
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• 1999

The estimation of reasonable amount of domestic cold water and hot water supplies in apartment houses is very important for the economical design of domestic cold water and hot water supply system which include pumps, boilers, heat exchangers, and various water reservoirs. To suggest the model of predicting reasonable amount of domestic cold water and hot water supplies, residents and actual domestic cold water and hot water consumption have been investigated for 740 apartment houses in Seoul and Bun-Dang, Kyunggi-Do. The model is suggested as a function of exclusive area of the apartment house and results of the model show generally good agreement with published data.

• Journal of the Korean Institute of Landscape Architecture
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• 제22권4호
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• pp.161-176
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• 1995

Leisure motivation is an important concept in the study of leisure behavior. The purpose of this study was to examine visitors' motivations for hot spring resorts in Korea. The data were collected by questionnaires survey in three hot spring resorts in 1994:Suanbo, Paikam, and Chuksan. The findings of this study are summarized as follows: The eight motivation factors extracted by factor analysis such as; 1)"intellectual needs", 2)'escaping everyday life', 3)'closing nature', 4)'recognition or status', 5)'interaction with others', 6)'health', 7)'family vacation', 8)'hot spring bathing'. The three resorts showed significant deferences in the motivation of visitors. Visitors of Suanbo have high motivation for 'intellectual needs', 'interaction with others', and 'thealth', and visitors of Chuksan for 'closing nature', 'family vacation', and 'hot spring bathing'. This study has proved first, psychological(pushing) factors are more important than pulling factors of resorts, second, in pulling factors, natural sceneries were more important than medicinal properties of the hot springs. And this study found several important implications for predicting visitors' demand in hot spring resorts.