• Korean Management Science Review
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• v.16 no.2
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• pp.79-92
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• 1999

This paper presents an automated visual inspection/measuring system for the door inner panel manufacturing process. The main objective of this research is to develop inspection applications with a machine vision system related to the determination or quantification of parameters such as dimension, shape, quality of surfaces, number of holes in a panel, and presence or absence of specific features. For quality measurements, we showed a subpixel image processing technology that will improve the consistency of results and level of precision. Also presented is a data analysis method th detect process shifts so that corrective action can be undertaken before more defective units are manufactured.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1999.11a
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• pp.25-34
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• 1999

In this study, the sliding wear in spur gears, using Archard's wear model, is analyzed. Formulas of tooth sliding wear depth along the line of action are derived. The tooth profile is modified Id make a smooth transmission of the normal loads and the cylinder profile for reducing the pressure spike is suggested. The sliding wear rate is calculated with these profiling results. We expect these modification methods to contribute to the reduction of sliding wear in the root and the tip of tooth and tooth edge.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.3073-3078
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• 2011

Driverless Train Control System has been recently introduced and commercialized in Korea. It is expected that the vehicle with driverless operation system will be used in new lines such as Sinbundang line soon. Therefore it is necessary to change the system operation and conception of the existing train operation system and the necessity of driverless vehicle monitoring system meeting a new paradigm is rising. In order to dispel concerning about safety issues caused by driverless train operation, the importance to establish vehicle error detection, useful fault diagnosis and rapid action plans is higher than ever. For this, efficient and higher level of vehicle supervision & control system should be essentially supported. In this study, remote driverless vehicle monitoring system using by radio communication is suggested to be used for monitoring and controlling important parts of the vehicle and diagnose and take quick actions when vehicles are in trouble at control tower at real time.

• Journal of Korean Society for Quality Management
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• v.12 no.2
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• pp.15-24
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• 1984

Since W.A. Shewhart (1931) developed the quality control method using the control chart, many theoretical and empirical works about such an analytical method have been done. However there are two major methods relating to the control chart analysis; the conventional 3 sigma control method and the warning limit method which has been suggested as a modification of the former. The conventional 3 sigma method requires to take a remedial action only when a quality characteristic is beyond the control limit (3 sigma). However, once a quality characteristic is over the control limit, searching and repairing an assignable cause requires time consuming job and high costs. Therefore if we set the warning limit between the central line and the control limit, we will be able to take remedial measures before too late. In spite of its advantage, much attention has not been paid to use the control chart with warning limit in Korean industries. The main object of this study is to examine improvement of quality and productivity when the control chart with warning limit is used.

• Proceedings of the KIEE Conference
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• 2009.07a
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• pp.278_279
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• 2009

Nowaday, many people study about Black-Out. In this paper, I introduce how to calculate the Dangerous Index against Black-Out, and prediction of Distance relay error action on Zone 3. we consider the real data by I-PIU which will be set on the system. The dangerous Index is calculated three index about Cascading. The prediction of Distance relay is considered by other facilities of power system. This two algorithm can be used on the center system, when the system is on danger, also on the normal states for security.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.16 no.8
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• pp.745-757
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• 1991

In this paper, the theoretical convergence property of the individual tap LMS algorithm for equaliz action if analyzed, and the pefomances over seeral multipath time vaing mobile radio channels are investigaed. The individual tap adjusting method of the tapped-elay line equalizer using LMS algorithm is proved to have Wiener optimum solution. It has more rapid convergence speed and lowe bit error rates than conventional Tdl LMS and gradient lattice equlizer in time invariant or time variant multipath channels.

• Journal of Microbiology and Biotechnology
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• v.17 no.12
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• pp.2056-2060
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• 2007

Transcription factor GATA-3 is the critical transcription factor for Th2 cell differentiation. In spite of its importance in Th2 cell differentiation, the molecular mechanism for its action in Th2 differentiation is poorly understood. Previous studies have suggested that GATA-3 may be involved in the chromatin remodeling in the Th2 cytokine locus. To determine whether GATA-3 exerts its effect on its target sites in the extrachromosomal status, cell transfection assay was performed. In this assay, 800 bp IL4 promoter-luciferase constructs linked with GATA-3 target sites were transfected into the M12 B cell line, D10 mouse Th2 cell lines, and human T lymphoma Jurkat cell lines with or without the GATA-3 expression vector. The GATA-3 effects on its target sites were minimal in the extrachromosomal status, supporting the previous propositions that GATA-3 functions at the chromatin level by remodeling chromatin structure.

• Journal of Preventive Medicine and Public Health
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• v.53 no.4
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• pp.233-235
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• 2020

Since its early stages, the coronavirus disease 2019 (COVID-19) pandemic has posed immense challenges in meeting the public health and healthcare and social care needs of migrants. In line with other reports from United Kingdom and United States, data from Sweden's health authority show that migrants have been disproportionately affected by COVID-19. Following the World Health Organization's statements, as well as the European Public Health Association's call for action, several centres in Sweden's most populated areas have activated tools to implement national plans for community outreach through initiatives targeting migrants and ethnic minority groups. Unconventional means should be promoted to mitigate the impact of COVID-19 on migrants and the health of the public at large.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.42-46
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• 1993

This paper presents development of a pratical tool deflection compensation system in order to reduce the machining error by the tool deflection in the end-milling process. The system is a tool adapter which includes 2-axis force sensor for detecting tool deflection and 2-axis tool tilting device for adjusting tool position through computer interface in on-line process. In experiments, it is revealed that the force sensor applying parallel plate principle and strain gauge is proper to obtain dynamic process signal, and the tilting device using stepping motor and cam drive mechanism is suitable to have necessary action. By the system and control algorithm, it is possible to get precise machining surface profile without excessive machining error and overcut generated due to increased cutting force in more productive machining condition.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.6
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• pp.163-167
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• 2007

A field emission electron gun including 3 electrodes including one cathode and two anodes is very important for high resolution electron microscope. To have functions to control the initially-emitted electron beam, two anodes act as an electrostatic lens according to equipotential lines by adjusting the spot size, intensity, and working distance. To verify the action of the electron beam by the electrostatic lens by changing several parameters such as electrode shape, displacement and applied voltage to the electrodes, the two lenses were design and simulated and then their performances were analyzed with angular beam intensity(distribution), electrical optic axis variation and their stability.