• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.314-318
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• 2002

Recently, new polishing tool which was made by magnetic intelligent compound(Magic) was invented. The distribution of abrasives in this new tool can be controlled by magnetic field. Therefore, we can make a special polishing tool which has well arranged abrasives after cooling. In this study, 3 dimensional polishing machine was developed in order to polish complicated - shaped inner surfaces of molds. The performance of developed machine was investigated by measuring the roughness of polished surface using new polishing tool.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.04a
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• pp.284-289
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• 2002

In this paper, we develop a six-axes machining center tool(MCT) and CAD/CAM system based RAD Tool Program. The MCT consists of two mechanical parts, i.e., a X-Y-Z Cartesian coordinate typed MCT and a parallel-typed tilting table. Kinematics and singularity are accomplished to design the parallel-typed tilting table, and RAD Tool Program Is developed for the six-axes MCT, which requires the commands of position as well as orientation for machining of complex shape. In RAD Tool, the CAD/CAM system has a tool path generator, NC code generator and a graphic simulator. This paper designs the parallel-typed tilting table to meet the desired specification and presents the results of CAD/CAM system based RAD Tool Program.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.04a
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• pp.317-322
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• 2004

This paper deals with a prediction method of tool life in view of the reliability assessment. In this study, the flank wear was studied among multi-factors deciding the tool wear state. Firstly, tool lift was predicted by correlation between flank wear and cutting time, based on the extended Taylor tool life equation of turning data, including parameters of cutting speed, feed rate, and cutting depth. Secondly, each of cutting conditions of endmilling was equivalently converted to apply ball endmill data to the extended Taylor equation. The web-based reliability prediction program for tool lift is being developed as one of reliability assessment programs to for the machine tools.

• Journal of Korean society of Dental Hygiene
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• v.13 no.5
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• pp.713-726
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• 2013

Objectives : The purpose of this study is to develop a job performance assessment tool for dental hygienists. Methods : The development consisted of three steps. The first step was to construct the contents of the assessment tool and a pretest questionnaire. In the second step, validity and reliability tests were done and modified for the pretest questionnaires and an assessment tool was made. The third step was verification of the assessment tool. A total of 678 data from the dental hygienists were analyzed to verify the validity and reliability. The assessment tool consisted of two areas such as job performance and competency/attitude: the job performance area covered four sub-areas including oral health education, preventive dental care, assistance for dental treatment, and administrative management. Results : The number of questions and reliability test result for each sub-area were as follows. Reliability coefficient for oral health education (10 questions) was 0.899, preventive dental care (8 questions) was 0.861, assistance for dental treatment (18 questions) was 0.915, administrative management (8 questions) was 0.919, competency of dental hygienists (11 questions) was 0.947, and attitude of dental hygienists (15 questions) was 0.955. Cronbach ${\alpha}$ coefficient for reliability of total 70 questions of the assessment tool was 0.980. Conclusions : The validity of the assessment tool was verified by three steps and the reliability proved to be significant. Consequently the assessment tool was found to be useful as an objective and valid job performance assessment tool for the dental hygienists.

• Communications of Mathematical Education
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• v.34 no.4
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• pp.587-603
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• 2020

This study is a basic study to effectively develop a mathematics experience object, an important tool and educational tool in mathematics education. Recently, as mathematics education based on action theory is emphasized, various mathematics experience objects are being developed. It is also used through various after-school activities in the school. However, there are insufficient cases in which a mathematics experience teaching tools is developed and used as a tool for explaining mathematics concepts in mathematics classrooms. Also, the mathematical background of the mathematics experience teaching tools used by students is unclear. For this reason, the mathematical understanding of the toolst for mathematics experience is also very insufficient. Therefore, in this study, a development model is proposed as a systematic method for developing a mathematics experience teaching tools. Also, in this study, we developed 'the Great Common Divisor' mathematics experience teaching tool according to the development model. Through the model proposed through this study and the actual mathematics experience teaching tool, the development of various tools for mathematical experience will be practically implemented. In addition, it is expected that various tools for experiencing mathematics based on mathematical foundations will be developed.

• The Journal of the Korea Contents Association
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• v.21 no.8
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• pp.403-412
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• 2021

As the number of mobile apps increases exponentially, automation of tests performed in the app development process is becoming more important. Until the app is released, iterative verification is performed through various types of tests, and this study was conducted focusing on the GUI test among various types of tests. This study is meaningful in that it can contribute to the stable app distribution of the developer by suggesting the development direction of the GUI test. To develop Android's GUI test tool, I collected basic data before presenting the development method by researching Android's UI controls and Material design guideline. After that, for the existing GUI test automation tool, two tools based on screen capture test and four tools based on source code analysis test were studied. Through this, it was found that existing GUI test tools don't consider visual design, usability, and component arrangement. In order to supplement the shortcomings of existing tools, a new GUI test automation tool development method was presented based on the basic data previously studied.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.923-924
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• 2008

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.319-320
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• 2008

• Journal of Korean Society of Industrial and Systems Engineering
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• v.15 no.26
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• pp.165-172
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• 1992

This paper develops the at location system of milling cutting tools to be used on NC milling machine tool by the technique of cluster analysis. The implementation concerning the tool management system will be applying to Flexible Manufacturing System efficiently.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.3
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• pp.75-81
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• 2003

Pocket machining is metal removal operation commonly used for creating depressions in machined parts. Numerically controlled milling is the primary means for machining complex die surface. These complex surfaces are generated by a milling cutter which removes material as it traces out pre-specified tool paths. To machine, a component on a CNC machine, part programs which define the cutting tool path are needed. This tool path is usually planned from CAD, and converted to a CAM machine input format. In this paper I proposed a new method for generating NC tool paths. This method generates automatically NC tool paths with dynamic elimination of machining errors in 2$\frac{1}{2}$ arbitrary shaped pockets. This paper generates a spiral-like tool path by dynamic computing optimal pocket of the pocket boundary contour based on the type and size of the milling cutter, the geometry of the pocket contour and surface finish tolerance requirements. This part programming system is PC based and simultaneously generates a G-code file.