• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2002년도 추계학술대회 논문집
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• pp.292-296
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• 2002

In the present investigation, the improvement of processing efficiency in the high speed machining of GC250 is explored. This study is to evaluate the tool performance in difficult-to-material using the new developed tool. Tool performance evaluation are conducted by tool wear, surface roughness, chattering in machined surface. The tool wear of A type was smaller than B type. In type B tool the chatter mark was observed in machined surface. The good surface roughness was obtained in type A tool. Consequently, the tool performance of A type is better than B type.

• 한국안전학회지
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• 제10권1호
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• pp.9-19
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• 1995

The recent development of NC lathe and machining renter have enabled automatic or unmanned manufacturing system for the improvement of production rate. And if you want to introduce automatic or unmanned manufacturing system into the cutting process of cage motor rotor, the selections of effective cutting conditions, rational tool grades and tool angles are necessary. As a result, the selection of cutting conditions, tool grades and tool angles are important factors to production rate.

• 한국안전학회지
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• 제10권2호
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• pp.46-55
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• 1995

The recent development of NC lathe and machining center have enabled automatic or unmanned manufacturing system for the improvement of production rate. And if you want to introduce automatic or unmanned manufacturing system into the cutting process of cage motor rotor, the selections of effective cutting conditions, rational tool grades and tool angles are necessary. As a result, the selection of cutting conditions, tool grades and tool angles are important factors to production rate.

• 기술사
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• 제32권6호
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• pp.44-47
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• 1999

This study deals with the quality strategy using brain science as the tool of productivity improvement. Especially, it is critically analyzed that the application of the brain theory to the new deployment methodology of quality management corresponds to the industrial improvement properly in points of performing quality and productivity, and contributing the growth of our society etc.

• 한국기계가공학회지
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• 제14권6호
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• pp.1-6
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• 2015

Tool condition monitoring plays one of the most important roles in the improvement of both machining quality and productivity. In this regard, various process signals and monitoring methods have been developed. However, most of the existing studies used cutting force or acoustic emission signals, which posed risks of interference with the machining system in dynamics, fixturing, and machining configuration. In this study, a feed motor current signal is used as a process signal representing process and tool states in tool breakage monitoring based on an adaptive autoregressive model and unsupervised neural network. From the experimental results using various cases of tool breakage, it is shown that the developed system can successfully detect tool breakage before two revolutions of the spindle after tool breakage.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2003년도 춘계학술대회 논문집
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• pp.1811-1815
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• 2003

Investigated is the relationship between tool deflection and geometrical accuracy in side wall machining. Form error is predicted directly from the tool deflection without surface generation. Developed model can predict the surface form error about three hundred times faster than the previous method. Cutting forces and tool deflection are calculated considering tool geometry, tool setting error, and machine tool stiffness. The characteristics and the difference of generated surface shape in up milling and down milling are discussed. The usefulness of the presented method is verified from a set of experiments under various cutting conditions generally used in die and mold manufacture. This study contributes to real time surface shape estimation and cutting process planning for the improvement of geometrical accuracy.

• 간호행정학회지
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• 제8권4호
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• pp.535-549
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• 2002

Purpose : The purpose of this study was to develop a core competency evaluation tool of the preceptors training new graduate nurses and to determine the validity of the developed instrument. Method : This study was conducted in 2 phases. In phase I, preceptor's core competency list was developed through literature review, focus group interview, and review by nursing directors and nurse managers. In phase II, 60 preceptors were evaluated with the developed instrument and categorized into excellent, good & poor core competency groups. For validation of the instrument, new graduates' clinical performance improvement and satisfaction with preceptor were compared between excellent and poor group. Result : The data were analyzed by SPSS P.C and the results were as follows. 1) Preceptor's core competencies were classified into three domains; Role model(10 items), Socialization facilitator(8 items), and Educator(16 items), and each item had four point system of "strongly agree" to "strongly disagree". Cronbach'${\alpha}$ of the instrument was.9416. 2) Comparison of clinical performance improvement and satisfaction with preceptor of the new graduates trained by excellent and poor preceptors revealed that new graduates' clinical performance improvement(p=.015) and satisfaction with the preceptor(p=.005) were significantly higher in the excellent core competency preceptor group than the poor core competency preceptor group. Conclusion : The validity of the preceptor's core competency evaluation tool developed in this study was confirmed. Therefore, this tool can be effectively utilized for education and evaluation of new graduates' preceptors in clinical settings.

• 공학교육연구
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• 제15권6호
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• pp.98-102
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• 2012

This paper diagnose subjects and measures the learning ability of students based on the goal of developing an assessment tool for education productivity based on multi-aspect evaluation conducted by ICEE at Honam University. Furthermore, develop an assessment tool for education productivity that provides a motive to bring detailed improvements in teaching methods through the diagnosis. In addition, a method for compensating the issues and improving the quality of subject is suggested to develop learning ability of students through applying the assessment tool. An integrated operated system of CQI is desired to be built along with quality improvement of education through measuring academic quality by studying the methods for enhancing academic and learning ability achievement from analysis of the curriculum provided in the "ABEEK program". Through this study the current state of education productivity is presented through analyzing the difference between students who participated in the "ABEEK program" and who did not participate, and operating a comparison between the student's comprehension on their majors and liberal arts by the multi-aspect evaluation that has been conducted for 2 years.

• 한국생산제조학회지
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• 제5권4호
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• pp.82-89
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• 1996

In this study, to choose the drilling m/c with analysis model for dynamic design of machine tool strctures, are used substucture syntheis method for reduction to degrees of freedom of dynamic model and analysis evaluation of substructures The dynamic factors of substurctures are examined by substructure synthesis method. And that dynamic design of structures for energy balancing are performed. The computer program for calculated of the dynamic and energy distribution analysis was developed. Result of numerical analysis by developed program obtained to conclusion as following. The design of machine tool structures by dynamic avoid the resonances, and are known to considered based on the energy balancing. These methods can be used effectively for the performance evaluation, design modification and improvement of dynamic performance evaluation, design modification and improvement of dynamic performance of machine tools.

• 한국기계가공학회지
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• 제20권12호
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• pp.100-106
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• 2021

This paper presents a study on the improvement of the machining quality of sculptured-surfaces of molds according to the shape and posture of the tool. In the existing 3-axis machining, the methods using the ball end-mill and radius end-mill were analyzed for various cutting patterns and compared with those of the 5-axis machining. It was observed that the 5-axis machining using a ball end-mill obtained the finest surface roughness, and for the 3-axis machining, the optimal results were obtained for the one-way machining using a radius end-mill.