• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.624-628
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• 2000

The performance of machine tools is qualified by many test procedures given by the national/international standards or respected organisations. Among them, test regarding circular-interpolation accuracy is getting to be one of the important acceptance tests at the production level. Machine tool systems are composed of many mechanical and electronical sub-systems so that it is not easy to improve dynamic performance by examining only one particular part. Instead, overall systematic approach encompassing all the contributing elements is necessary to achieve good results. In this study, measures taken in circular accuracy improvements will be explained case by case.

• Management & Information Systems Review
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• v.4
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• pp.595-610
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• 2000

This paper presents a study regarding a construction of the slide cases through the useful and practical design using presentation tool-Microsoft Powerpoint, which can offer to the person in charge with more useful and practical information for the construction of the slide cases. In this study, Presentation program is used to construct case in the slides. The results of this study may be summarized as follows : First, it is possible to construct useful and practical case in the slides with presentation program. Second, this study proposes directions for the construction of slides with presentation program.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.6
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• pp.1120-1126
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• 2002

Machining characteristics of tool steels manufactured by electro slag casting process has been investigated in this study. For the estimation of machinability, turning and drilling tests are carried out. The chip shapes at various velocities are investigated for the comparison of turning workabilities of tool steels because the chip shapes reflect characteristics of cutting resistance. In case of drilling test, feed motor currents measured by a hall sensor are used as a measure for the drilling resistance. The machining characteristics of the tool steels are strongly correlated with tensile properties, such as tensile strength, hardness, and ductility. In case of turning workability, it was found to be favoured by the higher tensile strength, while the opposite is true far the drilling workability. The electro-slag casted materials show better turning workability in the viewpoint of chip shapes and, the quenching-tempered electro-slag casted material has relatively better drilling machinability than that of the annealed one.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.12 no.6
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• pp.45-51
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• 2013

Friction stir welding using aluminum alloys has been widely applied for transportation vehicles because of the light specific weight, which can be used to obtain sound joint and high mechanical properties. This study shows the effects of rotation speed, welding speed, welding load, and tool shape on defect formation with extruded AA6005, which is used for railway vehicle structures of non-uniform thickness welded by friction stir welding using load control systems. Optical microscopy observations and liquid penetrant testing of each FSW joint were carried out in order to observe defect formation. Two kinds of defects, that of probe wear and that of lack of penetration in the bottom of the welded zone, were observed. In the case of using a taper shaped tool, the defect free zone is very narrow, within 100 kgf; however, in case of using a cylindrical shape tool, the defect free zone is wider.

• School Mathematics
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• v.6 no.4
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• pp.389-409
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• 2004

This article presents a case study in which three middle school students developed models in modeling activity using a tool. We research the interaction of model development process and the activities operating a tool in the modeling. And we investigate whether students are able to create generalizable model, after a tool mediates students' thought process and students internalize the perceptive activity operating a tool. The analysis of our case study led to three results. First, as students were able to integrate perceptive activity operating a tool and cognitive activity, they reasoned about the relationships among changing quantities and developed the model. Second, students corrected and refined developed models with reflecting the perceptive activity operating a tool. Third, as students internalized perceptive activity, students were able to create generalizable model, which is a graph of height as a function of the amount of water that's in the beaker.

• Journal of KIISE:Computing Practices and Letters
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• v.15 no.2
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• pp.140-144
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• 2009

The efficient test tool is indispensable to the test driven development. The test tool is very helpful to get the advantage of the test driven development. Many traditional automation test tool does not support standard script language and are not suitable to unit test. In traditional unit test tool, a code for the test is added at the source code. Such method makes the complexity of a source code and has a problem which must modify many part of the source code when the test case is changed. In this paper, we present a design technique of a flexible unit testing tool which makes a developer can modify easily the test case by using the standard java script in test driven development. We implement the test tool by this design technique to verify the availability of this technique.

• Journal of Engineering Education Research
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• v.16 no.3
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• pp.42-50
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• 2013

The main purpose of this study was to develop a program outcomes assessment tool using reflection journal. Reflection journal has recently come to gain more attention from school as an alternative assessment tool. Although numerous studies reconfirmed the educational importance and value of reflection journal as an assessment tool, research on the assessment tool of the engineering accreditation, based on education view is scarce. After literature reviews about the case studies on the program outcomes assessment, this study, to analyse the current assessment tools, and then, examined the educational implications of reflection journal as a program outcomes assessment tool. This study suggested the assessment tool using reflection journal for PO6 (teamwork) and PO11 (engineering ethics), one of the most important assessment items in engineering accreditation. In this study, we used the performance criteria, assessment criteria, rubric, and closed the loop to measure the teamwork and engineering ethics. The result of this study is significant in terms of guiding the future evaluation system development for program outcomes.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.1015-1018
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• 2002

Recently, many studies have been undergoing to reduce a working time in a field of machine tool. There are two ways of reducing a working time; to reduce an actual working time by heighten a speed of spindle and to reduce a stand-by time by shortening a tool exchanging time. ATC(Automatic Tool changer) belongs to the latter case. Fixed address type ATC that is being developed ill this study can store more number of tool in small space than magazine transfer type ATC relatively as well as shorten tool exchanging time. In this study, a simplified equivalent model of finite element method in order to analyze structure of fixed address type ATC.

• Management & Information Systems Review
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• v.6
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• pp.63-88
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• 2001

This paper presents a case study regarding a simple accounting information analysis method through the practical design using spreadsheet tool-Excel, which can offer to the management with more useful and practical information for the management decision-making. In this study, spreadsheet program is used to constitute case of the accounting information analysis method. Spreadsheet tool-Excel is easy to analyze the accounting information. And it can constitute a necessary program through function menu. In conclusion, the spreadsheet program should be used for quantitative analysis and evaluation on the accounting information. And it should be used to perform management activities. The results of this study may be summarized as follows: First, it is possible to constitute useful and practical case in the accounting information analysis method with spreadsheet program. Second, this study proposes directions for the accounting information analysis method with spreadsheet program.

• Proceedings of the Korea Information Processing Society Conference
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• 2004.05a
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• pp.853-856
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• 2004

국내 게임 산업은 여타 문화 산업과 비교하였을 때 상업화의 시기는 가장 늦었음에도 불구하고 2003 년을 기준으로 4 조를 넘을 정도로 급성장을 하였다. 그러나 게임 제작사의 95% 이상이 적자에 시달리고 있는데 이는 게임 제작과 관련하여 개발 단계에 있어 담당자의 역할 분배 및 각 단계에 대한 적절한 관리를 하지 못해 팀원간 의사소통, 게임제작 공정 생성물 관리, 핵심 기술 및 자원관리 등의 문제가 발생하기 때문이다. 이러한 문제점들은 CASE 툴을 통해서 해결이 가능하다. CASE 툴을 통해 게임제작 공정에 있어 팀원간의 의사 소통과 인력 및 자원 관리, 각 공정간 산출물의 버전 컨트롤 및 이력관리의 정보를 체계적으로 관리할 수 있도록 한다. 이에 본 논문에서는 ISO12207과 RUP 프로세스를 기반으로 게임제작 공정의 생산성과 효율성을 증가시킬 수 있는 게임제작 기획, 자원관리도구를 설계 및 구현하였다.