• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 1996.06c
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• pp.906-917
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• 1996

This study was conducted to find possible application areas of the by-products generated from the incineration of rice husk. To this end, a pilot-scale rice husk incinerator system was constructed and its performed test was carried. Major findings are summarized as follows. 1. The rice husk incinerator system developed in this study performed satisfactory in terms of thermal efficiencies. At the optimum operating conditions, thermal conversion efficiency and heat exchanger efficiency was 97% ad 60%, respectively, while overall thermal efficiency of the system was 58%. Under all conditions tested, temperatures in the combustion chamber were quite uniform and crystallization of SiO$_2$ in the ash was negligible. 2. NOx and SOx content in the flue gas was well below the legal limit but the CO concentration was around the legal limit. 3. Thermal energy from combustion was successfully recovered by a heat exchanger to provide hot water, ash was found a good supplementary cementing m terial, and the flue gas also was an acceptable $CO_2$ supplier to greenhouses.

• Journal of the Korea Society of Computer and Information
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• v.23 no.11
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• pp.67-74
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• 2018

The verification for the design limit margin of the power device for the information communication and surveillance systems using HALT(Highly Accelerated Life Test) reliability test is described. The HALT reliability test performs with a step stress method which change condition until the marginal step in a design and development phase. The HALT test methods are the low temperature(cold) step stress test, the high temperature(hot) step stress test, the thermal shock cyclic stess test, and the high temperature destruct limit(hot DL) step stress test. The power device is checked the operating performance during the test. In this paper, the HALT was performed to find out the design limit margin of the power device.

• Journal of the Korean Professional Engineers Association
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• v.32 no.6
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• pp.60-67
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• 1999

299 chemical analyses are used to study the characteristics of mineral and thermal waters in South Korea. Even though the concentration of chemical components in thermal waters are generally very low, mineral waters having components more than 1,000 ppm of dissolved total solid(TDS) are reached up to 19% total analyses data, In Germany, Japan or some other countries, mineral and thermal waters are detined not only by water temperature, but also by chemical components. The principle of Law in Japan in also almost same with the German regulations. However, the Law for thermal spring In Korea permit thermal water to be qualifiled only by water temperature. For including chemical characters into the regulations or Law of thermal spring, the limit values of TDS and other 9 micro components related to mineral and thermal waters was selected through this study.

• Journal of the Korean Professional Engineers Association
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• v.33 no.1
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• pp.75-82
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• 2000

299 chemical analyses are used to study the characteristics of mineral and thermal waters in South Korea. Even though the concentration of chemical components in thermal waters are generally very low, mineral waters having components more than 1,000 ppm of dissolved total solid(TDS) are reached up to 1975 of total analyses data, In Germany, Japan or some other countries, mineral and thermal waters are defined not only by water temperature, but also by chemical components. The principle of Law in Japan is also almost same with the German regulations. However, the Law for thermal spring In Korea permit thermal water to be qualifiled only by water temperature. For including chemical characters into the regulations or Law of thermal spring, the limit values of TDS and other 9 micro components related to mineral and thermal waters was selected through this study.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.58 no.10
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• pp.2022-2027
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• 2009

An supercritical once through boiler system has been used in the korea standard-type thermal power plant. It is critical in boiler operation that superheater temperature should be controlled within the specified limit. In this paper, control logic scheme is suggested for superheater temperature in once through boiler. Finally the simulation result using process model based simulator shows the validity of suggested control logic.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.37-41
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• 2002

Thermal characteristics of hydrostatic guideway is largely depended on the temperature of supplied oil. For improving the positioning accuracy of hydrostatic guideway, relationship between setting temperature of oil cooler and thermal characteristics is analyzed, and influence of thermal characteristics on positioning accuracy is also analyzed experimental1y in this paper. Laser scale which has 0.01 $\mu\textrm{m}$ of resolution is used as feed-back unit. From the experimental results, it is confirmed that positioning error and repeatability is minimize upto 0.21 $\mu\textrm{m}$ and 0.18 $\mu\textrm{m}$ when the temperature of supplied oil is setting equal to temperature of atmosphere, and also confirmed that thermal deformation, which occurs by the temperature deviation between table and rail or scale supporter, works as limit of repeatability in long time operation.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.39 no.2
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• pp.73-79
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• 2021

Recently there are growing interests on the energy conservation and emission reduction. In the fields of architecture and civil engineering, the energy monitoring of structures is required to response the energy issues. In perspective of thermal monitoring, thermal images gains popularity for their rich visual information. With the rapid development of the drone platform, aerial thermal images acquired using drone can be used to monitor not only a part of structure, but wider coverage. In addition, the stereo photogrammetric process is expected to generate 3D point cloud with thermal information. However thermal images show very poor in resolution with narrow field of view that limit the use of drone-based thermal photogrammety. In the study, we aimed to generate 3D thermal point cloud using visible and thermal images. The visible images show high spatial resolution being able to generate precise and dense point clouds. Then we extract thermal information from thermal images to assign them onto the point clouds by precisely establishing photogrammetric collinearity between the point clouds and thermal images. From the experiment, we successfully generate dense 3D thermal point cloud showing 3D thermal distribution over the building structure.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.3
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• pp.7-17
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• 2014

Power electronics modules are semiconductor components that are widely used in airplanes, trains, automobiles, and energy generation and conversion facilities. In particular, insulated gate bipolar transistors(IGBT) have been widely utilized in high power and fast switching applications for power management including power supplies, uninterruptible power systems, and AC/DC converters. In these days, IGBT are the predominant power semiconductors for high current applications in electrical and hybrid vehicles application. In these application environments, the physical conditions are often severe with strong electric currents, high voltage, high temperature, high humidity, and vibrations. Therefore, IGBT module packages involves a number of challenges for the design engineer in terms of reliability. Thermal and thermal-mechanical management are critical for power electronics modules. The failure mechanisms that limit the number of power cycles are caused by the coefficient of thermal expansion mismatch between the materials used in the IGBT modules. All interfaces in the module could be locations for potential failures. Therefore, a proper thermal design where the temperature does not exceed an allowable limit of the devices has been a key factor in developing IGBT modules. In this paper, we discussed the effects of various package materials on heat dissipation and thermal management, as well as recent technology of the new package materials.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.7
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• pp.196-202
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• 1999

Recent trend changes a criterion for evaluation of burner that environmental problem is raised as global issue. For efficient driving problem, the higher thermal efficiency and the lower oxygen in exhaust gas, burner is evaluated the better. For environmental problem, burner must satisfy $NO_{X}$ limit and CO limit. Consequently, 'good burner' means on whose thermal efficiency is high under the constraint of $NO_{X}$ and CO consistency. To make existing burner satisfy recent criterion, it is highly recommended to develop feedback control scheme whose output is the consistency of $NO_{X}$ and CO. This paper describes development of real time flame diagnosis technique that evaluate and diagnose combustion state such as consistency of components in exhaust gas, stability of flame in quantitative sense. This study focuses on wave length of luminescence from chemical reaction measurement of the luminescence via optical measuring apparatus and derive correlation with consistency of components in exhaust gas by image processing technique.

• Transactions of the Korean hydrogen and new energy society
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• v.7 no.1
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• pp.55-62
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• 1996

As an essential step for development of a duel injection hydrogen fueled engine which can obtain high thermal efficiency and power in overall operating range, performance and BFL(back fire limit) equivalance ratio in hydrogen fueled engine with external mixture are investigated. As the results, BFL equivalence ratio in hydrogen fueled engine with external mixture is approximately 0.7. It is deduced that controls of driving conditions are required in transient stage from external mixture type to inner injection type. And in order to increase thermal efficiency, it is also found that BFL equivalence ratio should be expanded as much as possible.