• Journal of the Korean Society for Precision Engineering
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• v.25 no.2
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• pp.57-64
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• 2008

This paper describes the development of a small lens molding system for manufacturing the small lens like lens of a cellular phone, a small digital camera and so on. In order to manufacture a small lens, firstly, the raw material for lens with spherical shape should be manufactured by processing a glass material, secondly, the mold inserted the raw material for lens should be heated till its molding temperature in the electric furnace, finally, the small lens is manufactured by applying the force using pressuring control system. In this paper, the small lens molding system with the function of force control and velocity control was developed. It is composed of an electric furnace and its temperature control system, a pressuring control system, a body, and so on. The temperature characteristic test of the electric furnace, the force and velocity characteristic test of the pressuring control system were carried out. It was confirmed that the developed system had good functions for manufacturing a small lens.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.10 s.181
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• pp.2597-2602
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• 2000

The most effective means of evaluating remaining life is through the creep testing of samples removed from the component. But sampling of large specimen from in-service component is actually impossible. So, sampling device and small-specimen creep tester have been applied. Sampling device has been devised to extract mechanically small samples by hemispherical, diamond -coated cutter from the surface of turbine rotor bores and thick-walled pipes without subsequent weld repairs requiring post weld heat treatment. A method of manufacturing small creep specimen, 2min gage diameter and 10min gage length, using electron beam welding to attach grip section, has been proven. Small-specimen creep tester has been designed to control atmosphere to prevent stress increment by oxidation during experiment. To determine whether the small specimens successfully reproduce the behavior of large specimens, creep rupture tests for small and large specimens have been performed at identical conditions. Creep rupture times based on small specimens have closely agreed within 5% error compared with that of large specimen. The errors in rupture time have decreased at longer test period. This comparison validates the procedure for fabricating and testing on small specimen. This technique offers potential as an efficient method for remaining life assessment by direct sampling from in -service high temperature components.

• Journal of the Korean Society for Library and Information Science
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• v.49 no.4
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• pp.31-52
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• 2015

This study attempts to diagnose the trend of operation of small libraries and suggest direction for promoting them through a fact-finding survey on small libraries. According to the study results, it was important to make efforts for improvement such as reflecting the trend of increasing number of small public libraries and apartment libraries of small private libraries, enhancing substantiality of small libraries, human resource allocation for enhancing professionalism of running libraries, introducing activation measures that can consider the current operation situation of public and private libraries, establishing cooperative system between public and small libraries and enhancing accuracy of statistics data. As for the ways of promoting small libraries, change of direction toward qualitative operation support rather than quantitative increase, attempts to stabilizing operation of public small libraries, enhancement of specialty of private small libraries and establishment of cooperative system, strengthening of legal standard for small library and induction of corporate participation through campaigns were suggested.

• Journal of the Korean Data and Information Science Society
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• v.18 no.4
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• pp.1179-1189
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• 2007

In this paper, we estimate the proportion of individuals having health insurance in a given year for several small domains cross-classified by age, sex and other demographic characteristics using the data provided by the National Center for Health Statistics(NCHS). We employ Bayesian as well as frequentist methodology to obtain small domain estimates and the associated measures of precision. One of the new features of our study is that we utilize the survey weights along with the model to derive the small domain estimates.

• Journal of the Ergonomics Society of Korea
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• v.2 no.1
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• pp.13-21
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• 1983

Small group activity in Korea was introduced from the United States as QC circle, ZD group movements and the like, but it has developed into a Korean style from so-called factory saemaul panel activities contributing much to the management of enterprises. Based on human motivation theory, the principles to activate small group activity is suggested on which a new diagnosis of small group activity is proposed here. It is consisted of checklist and radarchart. The factor to activate small group activity have been obtained in terms of multivariate analysis for data from the new diagnosis.

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.10a
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• pp.603-603
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• 2007

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.10a
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• pp.595-595
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• 2007

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.10a
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• pp.596-596
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• 2007

• Proceedings of the Korean Society of Veterinary Clinics Conference
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• 2007.10a
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• pp.597-597
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• 2007

• 한국태양에너지학회:학술대회논문집
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• 2011.04a
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• pp.241-245
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• 2011

Small hydropower is one of the many types of new and renewable energy, which South Korea is planning to develop, as the country is abundant in endowed resources. In order to fully utilize small hydropower resources, there is a need for greater precision in quantifying small hydropower resources and establish an environment in which energy sources can be discovered using the small hydropower resource management system. This study has given greater precision to calculating annual electricity generation and installed capacity of small hydropower plants of Han river system by inquiring into average annual rainfall, basin area and runoff coefficient, which is anticipated to promote small hydropower resources utilization. Small hydropower resource management system was also established by additionally providing base information on quantified small hydropower resources and analysis function and small hydropower generator status, rivers, basin, rainfall gauging station, water level gauging station etc.. Small hydropower resource management system can be used gather basic information for positive applications of small hydropower energy nationwide.