• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3144-3149
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• 2007

A numerical analysis for temperature distribution of four different materials such as iron, silicon, aluminum and PVC has been performed in this study to predict thermal behaviors of combined weapon systems in a large environmental tester. Thus, experimental conditions have been proposed using a calculating software (SolidWorks 2007 COSMOS FloWorks) to prepare for field tests and analyze heat flow inside the environmental tester and temperature distributions of materials. The boundary conditions of the analysis are composed of inlet and outlet conditions of the environmental tester with different pressures and the limit of low temperature of -30$^{\circ}C$. The soaking time of the system in the environmental tester has been calculated by this commercial program in this study to carry out the experiment.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.397-400
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• 2008

A numerical analysis has been performed in this study to predict thermal behaviors of combined weapon systems in a large environmental tester. Also, temperature distributions of the materials of the system have been measured for the experimental conditions. The calculated thermal flow characteristics and the measured temperature distributions of the materials for the weapon systems have been analyzed to prepare for field tests in the environmental tester. The boundary conditions of the analysis are composed of inlet and outlet conditions of the environmental tester with various pressures and the limit of low temperature of -25$^{\circ}$C. The soaking time of the system in the environmental tester has been obtained by developed programs in this study to carry out the experiment in the predicted conditions.

• Journal of environmental and Sanitary engineering
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• v.12 no.1
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• pp.77-83
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• 1997

An experimental research was conducted in order to study the treatment of waste reuse system using the membrane. Cell tester which supplied by Amicon was used to compare the fluxes of various membranes. Specially investigated items in the experiment were carried out by using 5 species of microfiltration membranes as to various MLSS concentrations. From the results, it is recognized from the cell test that 0.2 $\mu $m pore-sized membrane have the most effective performance at 2000mg/L of MLSS, and physical properties of membranes such as strength, deflection, elongation, structure of pore are more important than chemical properties in microfiltration membrane.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.19 no.5
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• pp.1228-1234
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• 2015

In this paper, a fuzzy controller using thermoelectric for temperature environmental tester is developed. The new structure of fuzzy controller based temperature environmental tester is proposed and implemented to maintain a stable temperature and improve temperature change speed. In order to evaluate the efficiency, an experiment is setup to compare PID controller with our proposed controller. The experimental results, we proved that our proposed fuzzy controller has better performance than PID controller.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.678-683
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• 2004

The most popular consolidation tester is a standard consolidatiion tester, which performs consolidation using the step load weight. However this apparatus is used to obtain only the vertical consolidation coefficient. Therefore the purpose of this study is to develope the horizontal consolidation cell for a horizaontal consolidation coefficient. Various size of tests have been peroformed to investigate the effect of scale effect. From the test results, it has turned out that this horizontal consolidation cell has a good function for a horizontal consolidation coefficient.

• ETRI Journal
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• v.45 no.3
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• pp.543-550
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• 2023

Electrostatic discharge (ESD) testing for human body model tests is an essential part of the reliability evaluation of electronic/electrical devices and components. However, global environmental concerns have called for the need to replace the mercury-wetted relay switches, which have been used in ESD testers. Therefore, herein, we propose an ESD tester using metal oxide semiconductor-controlled thyristor (MCT) devices with a significantly higher rising rate of anode current (di/dt) characteristics. These MCTs, which have a breakdown voltage beyond 3000 V, were developed through an in-house foundry. As a replacement for the existing mercury relays, the proposed ESD tester with the developed MCT satisfies all the requirements stipulated in the JS-001 standard for conditions at or below 2000 V. Moreover, unlike traditional relays, the proposed ESD tester does not generate resonance; therefore, no additional circuitry is required for resonant removal. To the best of our knowledge, the proposed ESD tester is the first study to meet the JS-001 specification by applying a new switch instead of an existing mercury-wetted relay.

• Journal of the Korean Society for Railway
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• v.8 no.2
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• pp.188-194
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• 2005

Aging characteristics of glass fabric/phenolic composites for tilting train subjected to combined environmental aging factors were investigated. A 2.5KW accelerated aging tester with a xenon-arc lamp was used to provide environmental aging factors such as temperature, moisture, and ultraviolet. A series of aging tests were conducted up to 3000 hours and several types of specimens were prepared along the warp direction and the fill direction. Mechanical degradations for tensile, flexural, and shear properties were evaluated as a function of exposure times through a material testing system. Thermal analysis properties such as storage shear modulus, loss shear modulus, and tan 3 were measured through a dynamic mechanical analyzer. Finally exposed surfaces of the composites were examined using a scanning electron microscope. According to the experimental results, mechanical properties and thermal analysis properties of glass fabric/phenolic composites were found to be slightly degraded as a function of exposure times due to combined environmental effects.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.414-416
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• 2003

As environmental conditions for memory products are increasingly high speed/high density, adopting diverse system configuration, it's more and more difficult for current component tester to adopt the actual condition of field application. If system test screening is realized in component level, test coverage failure can be made more secured in the initial stage, evaluation cost can be reduced and the effectiveness of investment for the facility can be maximized. Based on the above background, component automatic system tester was developed and showed off satisfactory results per each memory device family. In this paper, component quality stabilization strategy and cost saving for tester investment through future Quality monitoring and application to mass production will be presented.

• International Journal of Railway
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• v.1 no.3
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• pp.113-116
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• 2008

The long-tenn exposure of polymeric composite materials to extreme-use environments, such as pressure, temperature, moisture, and load cycles, results in changes in the original properties of the material. In this study, the effect of combined environmental factors such as ultraviolet ray, high temperature and high moisture on mechanical and thermal analysis properties of glass fabric and phenolic composites are evaluated through a 2.5 KW accelerated environmental aging tester. The environmental factors such as temperature, moisture and ultraviolet ray applied of specimens. A xenon-arc lamp is utilized for ultraviolet light and exposure time of up to 3000 hours are applied. Several types of specimens - tensile, bending, and shear specimens that are warp direction and fill direction are used to investigate the effects of environmental factors on mechanical properties of the composites. Mechanical degradations for tensile, bending and shear properties are evaluated through a Universal Testing Machine (UTM). Also, storage shear modulus, loss shear modulus and tan a are measured as a function of exposure time through a Dynamic Mechanical Analyzer (DMA). From the experimental results, changes in material properties of glass fabric and phenolic composites are shown to be slightly degraded due to combined environmental effects.

• Journal of Animal Environmental Science
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• v.7 no.2
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• pp.119-126
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• 2001

For the odor test, it was chosen the conventional spreader, the hose spreader, and its combination with disk harrow and spring harrow as a slurry spreader. By the odor tester (Kalmor-$\sum$) with dairy slurry, the conventional spreader has the average $\sum$ value of 270, which means that one fells substantial odor and torment. In the cases of hose spreader and its combination with disk harrow, $\sum$ value was 217 and 182 respectively, which means a normal person does not smell any odor. Spreading the swine slurry with a conventional spreader shows $\sum$ value of 440, which means one feels unpleasant. The hose spreader shows $\sum$ value of 258, which lies in the limit one feels some odor and torment. Its combination with disk harrow has $\sum$ value 184, which means that a normal person can not smell any more. For the conventional spreader, the odor intensity indices from air dilution sensual test and 3 point odor bag as a sensual test were 66.9 and 35.4 respectively. On the other hand, the indices were 9.65 and 11.10 by hose spreader and its combination with disk harrow, which were lower than that of the regulation for industry. Therefore, the developed hose spreader showed an excellent effect on decreasing odor. The correlation between the results from odor tester and 3 point odor bag has shown 0.997 by swine slurry.