• Journal of the Korean Society for Precision Engineering
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• v.29 no.10
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• pp.1070-1077
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• 2012

Virtual machine tools have been magnified recently as manufacturers could estimate performances of machine tools before design and manufacturing of them. However, it requires much time and efforts to make FEM models and predict precision of machine tools well because machine tools are composed of many joints such as bolt joints, LM joints, rotational bearing joints and mounts. Especially, we have studied computational modeling methods of bolt joints to predict precision of machine tools well in this paper. Stiffness and damping coefficients of bolt joints are investigated and generalized with respect to fasten forces through experiments and FEM analysis. Matrix 27 element of ANSYS is used and bolt joints are simplified as square areas with 8 nodes to apply stiffness and damping simultaneously. Additionally, coordinate transformation of matrix 27 for bolt joints is induced to apply to skewed bolt joints of machine tools and evaluate it using FEM analysis.

• Journal of the Korean Society of Earth Science Education
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• v.3 no.2
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• pp.89-98
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• 2010

In this study, we investigated and compared the standard of the present teaching tools & facilities in 16 cities and provinces. On the basis of this data, we suggested the standard of teaching tools & facilities according to the new curriculum. In the analysis of the present teaching tools & facilities, we divided the scope of facilities into 'the common one' and 'lab & practical room[common].' This study made it possible to easily recognize a facility by deleting a prep room from the names of facilities. Also, we prepared the standard plan for teaching tools by putting its focus on how to desirably manage the curriculum while giving the independence of a school to the maximum because of all sorts & great numbers of teaching tools.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.3 no.2
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• pp.133-137
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• 2003

Various bioinformatics tools for biological data processing have been developed and most of them are available in public. Most bioinformatics works are carried out by a composite application of those tools. Several integration approaches have been proposed for easy use of the tools. This paper proposes a new multi agent system to integrate bioinformatics tools in the perspective of workflow since the composite applications of tools can be regarded as workflows. For the easy integration, the proposed system employs wrapper agents for existing tools, uses XML-based messages in the inter-agent communication, and agents are supposed to extract necessary information from the received messages. This allows new tools to be easily added on the integration framework. The proposed method allows various control structures in workflow definition and provides the progress monitoring capability of the on-going workflows. In particular, agents in this system have the rule-based architecture which allows the defined rule set to be a special role agent. This feature provides fast and flexible agent development to aid in managing the complexity of bioinformatics application. This system has been partially implemented and has been proven to be a viable implementation for workflow-based bioinformatics tool integration.

• Journal of Surface Science and Engineering
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• v.29 no.5
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• pp.540-544
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• 1996

To apply the CVD diamond film to coated tools, it is necessary to make adhesion strength between diamond film and substrate stronger. So adhesion strength of diamond coated WC-Co tools using Microwave Plasma CVD and cutting test of Al-18mass%Si alloy using diamond cutting tools were studied. Diamond coating was carried out using Microwave Plasma CVD apparatus. Reaction gas was used mixture of methane and hydrogen. Substrate temperature were varied from 673K to 1173K by control of microwave output power and reaction pressure. By observation of SEM, grain size became larger and larger as substrate temperature became higher and higher. Also all deposits were covered with clear diamond crystals. XRD results, the deposits were identified to cubic diamond. An analysis using Raman spectroscopy, the deposit synthesized at lower substrate temperature (673K) showed higher quality than deposit synthesized at higher substrate temperature (1173K). As a result of scratch adhesion strength test, from 873K to 1173K adhesion strength decreased by rising of substrate temperature. The deposit synthesized at 873K showed best adhesion strength. In the cutting test of Al-18mass%Si alloy using diamond coated tools and the surface machinability of Al-Si works turned with diamond coating tools which synthesized at 873K presented uniform roughness. Cutting performance of Al-18mass%Si alloys using diamond coated WC-Co tools related to the adhesion strength.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.334-337
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• 2005

The objective of this research works is to propose a rapid development methodology of small size deep drawing tools for electronic parts utilizing the technology combination of CAE and RP/RT. The technology is applied to the development of deep drawing tools with a drain shape. The final surface of tools is obtained from the evaluation of the formability using the CAE. In order to manufacture the physical prototype of tools fer try-out terming, several fabrication experiments are carried out for three types of rapid tool manufacturing technology. Through the fabrication experiments, the acceptable rapid manufacturing technologies of deep drawing tools with a small size have been proposed.

• Educational Technology International
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• v.14 no.1
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• pp.55-74
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• 2013

The diversity of students is getting increased in the contemporary classroom. To deal with the diversity, differentiated instruction (DI) should be considered as a way of providing alternative approaches to content, process and product according to the students' readiness, interest, and learning needs. Teachers have problems and difficulties in supporting different student's needs. In fact, teachers need proven tools including framework, guidelines or computing systems to help to practice DI in real context. According to the activity theory, tools influence on how people act and think and even their social practice, playing a crucial role in mediating the activities with people. In DI practice, there are also some studies about physical and abstract tools, but they have been not widely utilized by teachers in real schools. It means that more innovative tool to promote DI might be required. Therefore, to design a better tool to mediate the DI activities with teacher, case studies were conducted. In order to elicit the design implications, two physical and two abstract tools for DI practice were analyzed as case studies. Through the analysis of the case studies, eight design implications better to facilitate DI practice were suggested. This study has implications in suggesting design guidelines for teachers' tools to facilitate their DI practice by analyzing case studies in DI practices for an innovative tool in the educational practice.

• Journal of the Ergonomics Society of Korea
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• v.34 no.1
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• pp.45-62
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• 2015

Objective: The purpose of this study is to investigate the effect of personality type on human performance tool compliance in nuclear power plants (NPPs) and to propose general recommendations for an enhancement of its practical utilization. Background: Various guidelines, regulating criteria, and recommendations have been developed to prevent human errors in NPPs. Despite these efforts, the accidents sometimes caused by human errors have steadily occurred, and therefore, various human performance tools have been adopted as countermeasures against human errors. The major and inevitable contributing factors among the many hazards to human errors might be the trait and personality, which are considered to be the inner world of humans. Thus, we try to investigate the utilization of human performance tools by considering the different types of operating crew personalities, and we suggested more practical recommendations to prevent human errors according to the personality. Method: We developed the Questionnaire using the Big 6 (HEXACO) models, which are human performance tools for workers in NPPs, and individual (condition) variables to investigate the effect of personality types on human performance tools. We slightly modified them to help the survey respondents understand them better. A survey was conducted for ordinary people over the age of 20. SPSS 22.0 was used to perform a correlation analysis and a hierarchical regression analysis to find the relationship between personality types and human performance tools. Results: The utilization of human performance tools shows significant differences statistically by personality. The correlation result reveals that the types of Honesty (H), Extraversion (X), Conscientiousness (C), and Openness to experience (O) show a higher utilization of human performance tools. In hierarchical regression results, human performance tools of task preview, questioning attitude, stopping when unsure, self-checking, effective communication, and place-keeping show a higher utilization with personality types. However, the Agreeableness (A) type did not show significant differences statistically with human performance tools. Conclusion: We tried to investigate the utilization of human performance tools by considering the different types of human personality and provide more practical recommendations to prevent human errors according to the personality. These results will be able to prevent human errors owing to the characteristics (advantages and disadvantages) of personality types. Application: This information can be utilized as guidelines for proactive recommendations according to the workers' personalities for more practical human performance tools to prevent human errors in an NPP.

• Journal of Korean Society for Quality Management
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• v.28 no.1
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• pp.132-150
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• 2000

TQM is considered as a kind management innovation tools. Managers are apt to be embarrassed in face of too many emerging and diminishing faddish management innovation tools. In spite of their expected usefulness, the result of implementation used to be depressing. One of the most important things for successful implementation is to understand their correct usefulness and characteristics. This paper analyzes the characteristics of TQM as innovation tool by comparing TQM with other management innovation tools in terms of criteria derived in view of competitive strategy formulation.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.871-872
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• 2006

Nowadays the market for diamond tools grows rapidly. The present decline in the price of industrial diamond makes it a commoditised product capable of competing with conventional abrasives. In terms of production volume, the largest group of diamond tools comprises the metal-bonded diamond impregnated tools, such as sawblades, wire saws, and core drills for cutting stone and construction materials, and core bits for mining applications. This article provides a compendious coverage of the powder metallurgy (PM) diamond tool-making routes, and identifies the recent trends towards changing the tool design and composition to render it cheaper and more efficient.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.365-369
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• 2002

This paper introduces that the machine tools's feed system optimizes by modeling for simulation and adjusting drive control parameter. The first method is frequency response of speed loop with design parameter by use of MATLAB application, in order that other axis can do equal to bandwidth. The second meted uses various sensor for analyzing machine tools's structure and adjustes jirk limitter.