• Proceedings of the KIEE Conference
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• 1999.07b
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• pp.671-673
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• 1999

In order to cope with the occurrence of abnormal operation, rotatory condition monitoring system for guide roller of finishing train in wire rolling has been developed. In this study, proximity sensor and its holding devices that could overcome severe in-situ measurement conditions was designed and MMI software using C++ was programmed. Performance of the developed system turned out to be good enough as results of in-line test for POSCO #3 wire rolling mill. It is expected to contribute to prevent the cobble and the grade-down of products caused by the abnornormal operation of guide rollers.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1998.10a
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• pp.196-202
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• 1998

Because the journal and bearing surface are fully separated by the oil film during the normal operation, fluid film bearings operating in the hydrodynamic lubrication region are expected to have an infinite life. However, there are many parameters that lead to interfere with the normal operation of the bearing and lead to its failure. In this paper, both the causes and countermeasures of the bearing failure are described. Also, the characteristics of wiped bearing surface are investigated through mechanical and chemical test.

• Proceedings of the KIEE Conference
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• 2002.11b
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• pp.227-230
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• 2002

A 765kV Transmission line system plays an important role in delivering the electric power produced at mid-western in Korea. This system will be constructed and operated normally on 2002. By doing the number of test operation in a given time, the reliability on the operation of 765kV transmission system could be secured.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.05a
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• pp.329-334
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• 2002

Preliminary test for the design and construction of a tuned dynamic absorber is a conducted. Proposed tuned dynamic absorber is a cantilevered beam type, and is supposed to adjust its natural frequency according to the changing operation condition of the primary system. The modal mass of the dynamic absorber is the easiest to control, therefore, the position of the attached mass of the dynamic absorber is considered as the main design parameter of the absorber. The effect of the dynamic absorber is experimentally verified under various operation conditions of the primary system.

• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.2
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• pp.40-48
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• 1992

A model using a linear programming technique was developed to operate gates for the optimum management of small of medium size agricultural reservoirs. To predict the inflow into the reservoirs the WASHMO model, which was a single event hydrology model, was modified and used. To test the applicability, the developed model was applied to two reservoirs located in Kyungpook province. The results showed that the model could be used for the optimum gate operation of the agricultural reservoirs.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.40 no.7
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• pp.474-480
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• 2003

We designed and tested a new scan driver output stage. Compared to conventional CMOS structured scan driver IC′s, the new NMOSFET-only scan driver circuit can reduce the chip area and therefore, the chip cost considerably. We confirmed the circuit operation with open drain power NMOSFET IC′s by driving 2"PDP test panel. We defined critical device parameters and their optimization methods lot the best circuit performance.

• Water Engineering Research
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• v.3 no.1
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• pp.57-62
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• 2002

This research is intended to integrate long-term operation rules and real time operation policy for conservation & flood control in a reservoir. The familiar Yield model has been modified and used to provide long-term rule curves. The model employs linear programming technique under given physical conditions, i.e., total capacity, dead storage, spillways, outlet capacity and their respective elevations to find required and desired minimum storage fur different demands. To investigate the system behavior resulting from the above-mentioned operating policy, i.e., the rule curves, the simulation model was used. Results of the simulation model show that the results of the optimization model are indeed valid. After confirmation of the above mentioned rule curves by the simulation models, gate operation procedure was merged with the long term operation rules to determine the optimum reservoir operating policy. In the gate operation procedure, operating policy in downstream flood plain, i.e., determination of damaging and non-damaging discharges in flood plain, peak floods, which could be routed by reservoir, are determined. Also outflow hydrograph and variations of water surface levels for two known hydrographs are determined. To examine efficiency of the above-mentioned models and their ability in determining the optimum operation policy, Esteghlal reservoir in Iran was analyzed as a case study. A numerical model fur the solution of two-dimensional dam break problems using fractional step method is developed on unstructured grid. The model is based on second-order Weighted Averaged Flux(WAF) scheme with HLLC approximate Riemann solver. To control the nonphysical oscillations associated with second-order accuracy, TVD scheme with SUPERBEE limiter is used. The developed model is verified by comparing the computational solutions with analytic solutions in idealized test cases. Very good agreements have been achieved in the verifications.

• Journal of Korean Society of Rural Planning
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• v.27 no.2
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• pp.23-34
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• 2021

This study aims to understand why the sales volume and the number of visitors are different in each rural tourism village. The study considered that the management and operation of rural tourism villages is one of the major influencing factors. To prove this, the study determined what factors were related to the management and operation of villages and derived detailed items to evaluate them. In the study, the researchers conducted an in-depth interview and a literature review on the management and operation of rural tourism villages in Yangpyeong-gun. They also performed a case study on the Sumi village, one of the successfully managed and operated villages in Yangpyeong-gun, to determine the detailed items. As a result, seven factors were identified. These factors comprise operation entity, governance, shared vision, leadership, efficient role-playing, marketing efforts, and equity in profit distribution. Based on these seven factors, 85 of the evaluation items were developed. The management and operation scores of 85 items were measured and summed for each of the 21 rural tourism villages. First, 21 villages were divided into two groups by the sales figures to derive items to determine the difference in the mean value of the evaluation scores. Second, an independent sample t-test was conducted for each village at YangPyeong-gun. Third, the study divided the 21 villages into four groups using 46 evaluation items. Finally, the study's researchers clarified some challenges to solve and appropriate management and operation plans considering each type of rural tourism village.

• Proceedings of the Korean Nuclear Society Conference
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• 2005.10a
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• pp.891-892
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• 2005

• 한국도로학회:학술대회논문집
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• 2003.10a
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• pp.303-310
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• 2003