• Journal of the Korean Society of Manufacturing Technology Engineers
• /
• v.7 no.4
• /
• pp.104-116
• /
• 1998

This paper provides a review of the performance for SM45C using the CNC lathe. Under the constant cutting area, the tool wear for large feed rate is more than the small feed rate, and the progress goes more rapidly as the cutting speed is increased. This is caused by the friction between the workpiece and the bite. The average cutting force increases as the feedrate increases, and decreases as the cutting speed increases. This is because the effective rake/shear angle becomes smaller as the feedrate becomes larger. The higher is the cutting speed and the aspect ratio (the ratio for depth of cut to feedrate), the lower is the cutting force and the surface roughness. Also, for the optimal selection of the cutting conditions, many experimental graphical data were obtained. That is, the cutting force, the tool life, and the surface roughness were measured and investigated as the depth of cut and the feedrate changed. And the size effect was examined as the depth of the cut varied.

• Journal of the Korean Society for Precision Engineering
• /
• v.8 no.4
• /
• pp.84-94
• /
• 1991

In order to achieve high accuracy of teaching and increase productivity using industrial robots in polishing process of dies, an off-line task programming system was developed on IBM-PC/386 under WINDOWS 3.0 operating system. The internal structure and the machematical basis of CAMPoli are described. Surface modeling technique of polishing dies with sculptured surfaces is introduced by poing data interpolation methodology through the use of CL-data transmitted from conventional CAM system. Tool selection, polishing speed, polishing pressure and kinds of tool motions can be determined and selected by user specified polishing variables. Task creation and verification of polishing path via computer graphics simulation of polishing tool can be done by the menu- driven function of CAMPoli system. Post-processing module is attached to generate robot language. Some simulation results are provided as verification means of the system.

• Journal of the Korean Society for Precision Engineering
• /
• v.17 no.5
• /
• pp.173-179
• /
• 2000

While a cutting tool is machining a workpiece at various cutting depth, the feedrate is usually selected based on the maximum depth of cut. Even if this selection can avoid power saturation or tool breakage, it is very conservative compared to the capacity of the machine tools and can reduce the productivity significantly. Many adaptive control techniques that can adjust the feedrate to maintain the constant cutting force have been reported. However, these controllers are not very widely used in manufacturing industry because of the limitations in measuring the cutting force signals. In this paper, turning force control systems based on the estimated cutting force signals are proposed. A synthesized cutting force monitor is introduced to estimate the cutting force as accurately as a dynamometer does. Three control strategies of PI, adaptive and fuzzy logic controllers are applied to investigate the feasibility of utilizing the estimated cutting force fur turning force control. The experimental results demonstrate that the proposed systems can be easily realized in CNC lathe with requiring little additional hardware.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 1999.10a
• /
• pp.485-491
• /
• 1999

A burr is formed in every corner of parts as a result of machining, which produces undesirable edge geometry and influence deeply to surface quality of workpiece. Therefore these burrs must be removed certainly. The cost of removing these burrs is directly proportional to their size. Burrs have been among the most troublesome obstruction to high productivity and automation of machining processes. The proper selection of cutting condition and tool geometry will be helpful to reduce the occurrence of burrs. In paper will observe burr formation along helix angle in end milling and certificate experimentally mechanics relation of helix angle and burr formation.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1995.04b
• /
• pp.429-433
• /
• 1995

Compound solid is maded for specially fixed object. A number of compound soild are devided as a unit germetric solid. The special case of rotation about an arbitrary axis makes according selection modelfor transformation. View plane and View region are estiblished for back face removal. After back-face removal eachedge is checked for point of intersection. The designing of of fset surface id maded and tool-path gernerted on the part surface. In tersection point is checked among the offset surfaces. The paper used an efficient algorithm for generating tool paths to apply a notion view volume. Through machining experiments with a 3-axis machining centre, the adequacy of the analysis was confirmed.

• Journal of Korean Society of Industrial and Systems Engineering
• /
• v.23 no.55
• /
• pp.85-96
• /
• 2000

This paper describes IDMS, a graph-based modeling system that supports problem structuring. We employs influence diagram as a problem representation tool, that is, a modeling tool. In particular, IDMS is designed as domain-independent shell. Therefore, a modeler can change the contents of the knowledge base to suit his/her own interested domain. Since the knowledge base of IDMS contains both modeling knowledge and domain knowledge, IDMS provides not only the syntactic support for modeling tool, but also the semantic support for problem domain. To apply the method in the real world context, we tested IDMS on the process selection problem in business reengineering, which is typical semi-structured problem.

• Journal of KIISE:Computing Practices and Letters
• /
• v.15 no.6
• /
• pp.440-444
• /
• 2009

In order to improve the effectiveness of software process improvement, more than two models can be use to compensate the weakness of each other. One of integrated models is the one in which CMMI and software six sigma. However, it is very difficult for a small software development organization to select and apply an appropriate set of six sigma tools since there are a lot of six sigma tools and statistical knowledge is required. In this paper, we suggest a six sigma tool selection process to help small organizations select six sigma tools effectively based on organization business value. Thereby, small organizations can efficiently implement CMMI by adopting an appropriate set of six sigma toolkits.

• Journal of the Korean Society of School Health
• /
• v.25 no.1
• /
• pp.1-13
• /
• 2012

Purpose: This study was intended to identify the competency model for korean health teachers. In order to enhance job effectiveness and talent development of health teachers in schools, this study would provide policy makers and school administrators with a competency model to be used as a valid and reliable tool for selection, development, and appraisal of health teachers. Methods: This study used three-round Delphi technique, which was a series of surveys to obtain a consensus of experts in school health and health education. 31 experts were finally involved in Delphi panel, which consisted of professors, administrators, and school teachers. Results: This study found that the competency model of health teachers was composed of fourteen competencies and 75 performance indicators. The fourteen competencies were as follows: consulting and teaching competency, students understanding competency, health problem solving competency, health assessment competency, relationship building competency, information management competency, curriculum management competency, teaching activity competency, writing competency, professional expertise competency, health business management competency, self control competency, school commitment competency, and achievement orientation competency. Conclusion: Based on the results of this study, policy makers and school administrators would be able to use the competency model as a tool of new health teachers selection, existing health teachers appraisal, and new and existing teachers training and education. Future research needs to classify the levels of each performance indicator as a kind of behavior indices.

• Journal of the Korea Convergence Society
• /
• v.12 no.5
• /
• pp.267-274
• /
• 2021

This study was designed to investigate the variables affecting Chinese university students' selection factors for Korean drama. Participants in this study were 379 university students from Hunan Province, China. An online survey program(www.wjx.cn) was used to collect data for this study. The tool of this study was 'a tool for measuring the selection factors of Korean Dramas', and it was composed of two areas: completeness of work and recognition. The results of this study are as follows: First, the completeness of work factor are higher than the recognition of Korean dramas by Chinese university students. Second, there are differences in the factors for selection Korean dramas according to the gender, grade, age, major, and Korean Drama watching frequency of Chinese university students. Third, when Chinese university students select Korean Dramas, their preferred genre influences the selection factors for the level of work completion and recognition. Finally, it was discussed according to the results of this study, and suggested for the qualitative re-leap of Korean Dramas in the global era. In order to expand the Korean Wave market in China, cultural contents must be developed to embrace the sentiment of Chinese university students, a propagation strategy that reflects the latest consumption trends of Chinese youth must be established, and the sophisticated visual beauty of Korean Dramas must be realized.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.16 no.12
• /
• pp.2575-2580
• /
• 2012

The aim of this paper is to analyze factors for site selection of the cloud data center and to develop spatial data model considering disasters information based on the GIS. In this paper, historical areas of the natural and human disaster are considered to analyze location of the cloud center. The model is developed using ArcGIS S/W tool. The model is applied on Busan city using disaster data from storm and flood, and small administrative district located Kang-Seo-Gu is selected as site selection of the cloud data center of Busan.