• Journal of the Korean Society for Precision Engineering
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• v.23 no.2 s.179
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• pp.73-80
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• 2006

High speed machining(HSM) technique is widely used in the appliance, automobile part and mold industries, because it has many advantages such as good quality, low cost and rapid machining time. But it also has problems such as tool breakage, smooth tool path, and so on. In particular, small size end mill is easy to break, so it must be changed before interrupting operation. Generally, the tool life of small size end mill is affected by the milling conditions whose selected parameters are spindle speed, feedrate, and width of cut. The experiments were carried out by full factorial design of experiments using an orthogonal array. This paper shows optimal combination and mathematical model for tool life, Therefore, the analysis of variance(ANOVA) is employed to analyze the main effects and the interactions of these milling parameters and the second-order polynomial regression model with three independent variables is estimated to predict tool life by multiple regression analysis.

• Korean Journal of Health Education and Promotion
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• v.18 no.3
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• pp.117-131
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• 2001

This study was attempted to develope a highly reliable and valid tool which is useful to assess the Korean obese adolescents' stress and coping method. The data were collected from the total of 600 obese students from middle and high schools in Pusan. The author used a convenience sampling method. The data collection was done from March 2 to July 11, 1999. The analysis of the data was done with SPSS Win(10.0) for descriptive statistics and factor analysis. The preliminary tool was composed of 72 items(stress items: 34, coping method items: 38) with the five point Likert scale. Item analysis and inter consistency were calculated for reliability and validity through pre-test. The preliminary tool was analyzed for reliability and validity. Finally, the tool was of 65 items(stress items: 33, coping method items: 32). The results were as follows: 1. Cronbach Coefficient Alpha for the 33 items of stress was .9485 and the 32 items of coping method was .8534. 2. The factor analysis was done in order to confirm construction and the items were extracted Oblimin rotation and Maximum likelihood extraction method. 3. The factor analysis showed 6 factors in stress and 10 factors in coping method. These 6 factors of stress explained 62.4％ and 10 factors of coping method explained 57.4％. 4. Six factor of stress lable were 〈outward appearance〉, 〈boyfriend/ girlfriend〉, 〈occur an outbreak of disease〉, 〈mutual relation of family〉, 〈an obese figure〉, 〈be a burden on exercise〉. 5. Ten factor of coping method lable were 〈be concerned about another affairs〉, 〈recreation activities〉, 〈self-violence〉, 〈relaxation〉, 〈hobby activities〉, 〈avoid a situation〉, 〈communication〉, 〈music〉, 〈negative behavior〉, 〈positive thinking〉. The results of using this scale in a study will contribute to design an appropriate school health management of obese students, and also it will contribute to the development of nursing research.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.4
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• pp.99-107
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• 2000

In this study, a static and dynamic characteristics analysis system for machine tool spindle systems with 3 lobe sliding bearing is developed based on Timoshenko theory, finite element method and windows programming techniques. And the characteristics value of 3 lobe sliding bearing such as eccentricity ratio, attitude angle, friction coefficient , stiffness coefficients, damping coefficients and so on, are determined by using the thermal equilibrium conditions of spindle systems. Since the developed system has various analysis modules related to static deformation analysis, modal analysis, frequency responses analysis and so on, it can be utilized to perform systematically the design an devaluation process of spindle systems with 3 lobe sliding bearing under windows GUI environment.

• Proceedings of the KIEE Conference
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• 2005.10c
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• pp.299-301
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• 2005

The urban transit system is operated by driverless and automatic.In driverless and automatic system, the system function is accomplished exactly to obtain the safety and reliability of system and the system is designed to minimize risk. In order to design the system, the functional analysis is performed. Recently functional analysis is performed by design toolwhich is used and verified by aerospace, military, etc. Generally, the design tool is used to perform functional analysis in urban transit system development project. The design toolassist the system engineer to analysis the function of system in basic design. Therefore, In this paper, it is performed the functional analysis to satisfy the system requirement of urban transit system and to confirm the operation of system using design tool.

• Transactions of the Korean Society of Mechanical Engineers
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• v.6 no.4
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• pp.384-389
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• 1982

It is necessary that machine tool structures should be designed so that they will cause a minimum chance of machining chatter. In order to do this, a computer program package is developed utilizing Finite Element Method, modal flexibility and energy balance method. Validity of the program package is verified through computer simulation analysis and impulse test of a simplified machine tool structure.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1993.10a
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• pp.638-643
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• 1993

The three dimensional finite element models for the basic deflection of linear motion guides and ball screws were developed. Form the comparison of the results calculated by the finite element method with those by the experiment, it was proved that the modeling method might be applied to real machine tool structures. Form the structural analysis of the headstock of the machine tool, it was found that the static stiffness was calculated within 6.5% error

• Journal of the Korean Operations Research and Management Science Society
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• v.20 no.3
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• pp.77-104
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• 1995

Intelligent Decision System support the decision analysis process in the managerial problems with decision analytic knowledge as well as domain specific knowledge. Influence Diagram has been one of the major knowledge representation in the intelligent decision system. In the development of intelligent decision system, knowledge acquisition is also known to be difficult. This paper suggests a developing tool using an influence diagram and Verbal Protocol Analysis which facilitates knowledge acquision for intelligent decision system. An ennvironmental decision making problem is used as an illustrative example and validation of the suggested developing tool is discussed. The suggested tool is very flexible to be expanded or applied to similar problems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.12
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• pp.652-658
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• 2016

In this paper, the theoretical research and simulation using the Finite Element Method (FEM) to design and form a micro-pattern for an ultrasonic horn is described. The present method is based on an initial design estimate obtained by FEM analysis. The natural and resonant frequencies required for the ultrasonic tool horn used for forming the fine pattern were predicted by finite element analysis. FEM analysis using ANSYS S/W was used to predict the resonant frequency for the optimum technical design of the ultrasonic horn vibration mode shape. When electrical power is supplied to the ultrasonic transducer, it is converted into mechanical movement energy, leading to vibration. The RFID TAG becomes the pattern formed on the insulating sheet by using the longitudinal vibration energy of the ultrasonic tool horn. The FEM analysis result is then incorporated into the optimal design and manufacturing of the ultrasonic tool horn.

• Journal of the Korea Convergence Society
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• v.12 no.9
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• pp.161-168
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• 2021

As the demand for high speed and high precision increases in the field of machine tool, interest in stiffness and vibration of machine tool is increasing. However, it takes a lot of time to develop a detailed design of machine tool based on experience, and it is difficult to design appropriately. Recently, structural optimization using FEM are increasingly used in machine tool design. But, it is difficult to optimize in consideration of the vibration state of the structure since optimization through stress distribution of a structure is mainly used, In this paper, Static structural analysis, mode analysis, and harmonic analysis using FEM were conducted to optimize the head structure that has the most influence on machining in a 5-axis machine tool. It is proposed a topology optimization analysis method that considers both static stiffness and dynamic stiffness using objective function design.

• Journal of Sasang Constitutional Medicine
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• v.28 no.1
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• pp.1-10
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• 2016

Objectives SCAT (Sasang Constitution Analysis Tool) is a system designed to provide the information needed to diagnose a sasang constitution diagnosis expert diagnosis. In order to determine the sasang constitution diagnosis requires the following four ways. This system provides objective information to the constitution diagnostic expert to collect such information.Methods SCAT was constructed by considering the user UI/UX to be easy to enter information. To provide a state of the subject in Table to make it easier to grasp the information of the subject also in constitution diagnostician.Results Provides objective data for experts to determine the constitutional history of the subject.Conclusions Professionals and ordinary users through the SCAT system can easily access the sasang constitution diagnosis. In the future through the advancement of the SCAT system will improve the user's convenience stability.