• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.587-588
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• 2012

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집C
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• pp.502-506
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• 2001

This paper presents a new method for cutting steel with a diamond tool using electrolysis. The electrolysis is adopted in the diamond cutting to prevent the high chemical activity between a diamond tool and an iron-based workpiece. The basic principle of the method is to oxdize a thin substrate of the workpiece by electrolysis ahead of the diamond tool which cuts the oxidized layer. A desired shape can be obtained by repeating this process. The cutting force is reduced because the diamond tool removes only the weakened material by electroysis. The reduction of the cutting force suppresses the excessive wear of the diamond tool. The oxidization penetrates several micrometers in depth along the previously formed shape. The corrosion rates depend on current density and make suggestions on the optimum cutting conditions.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2003년도 추계학술대회
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• pp.356-361
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• 2003

Electrochemical micromachining which is not normally considered as a precision process is presented in this paper. The application of voltage Pulses between a tool electrode and a workpiece in an electrochemical environment allows the three-dimensional machining of conducting materials with micrometer precision. In this paper tool-electrodes($5\mu\textrm{m}$ in diameter, 1mm in length) are developed by electrochemical micromaching and micro holes are manufactured using this tool-electrodes we developed already. Micro holes are achieved the accuracy below $50\mu\textrm{m}$ in diameter using ultrashort voltage pulses(0.1-5$\mu\textrm{s}$).

• 대한간호학회지
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• 제29권6호
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• pp.1294-1303
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• 1999

The purpose of this study was to develop a tool to assess the powerlessness and to measure the powerlessness of elderly. From the result of pre-test, twenty seven items were finally selected to survey the elderly's powerlessness. The questionnaires on the elderly's powerlessness were drafted so that such tool may be evaluated in accordance with the four point Likert Scale. The number of subjects is 1,150 with ages of 60 years or more and who live in a large city, a small and middle-sized city and a rural area. The subjects of the test and retest were 85 elderlies. Collected data were analyzed by utilizing SAS program with Cronbach's $\alpha$ and Pearson's correlation, factor analysis method and known group techniques, descriptive statics, t-test and ANOVA. The results from this study were summarized below:1. When the factor analysis method was applied for validity, the tool for powerlessness of elderly was separated into 5 factors: loss of self-confidence to deal with physical, emotional, social aspects of life; expulsion by others from meaningful human relate; perception that life is meaningless and time passes quickly; falling behind young people; being rejected by other people, having no influence on others. An application of the known group technique showed a significant difference with the result of the degree of elderly's powerlessness tools developed by the two groups, with illness and without. 2. In testing reliability, it was found that coefficient of test-retest was .9435(P<.0001) when the test-retest method was used as a test of stability, and that the alpha coefficient of internal consistency was .9141 over all items within the tool of elderly's powerlessness 3. In powerlessness of elderly, total mean is 2.8493. And in factor of powerlessness, the highest factor is falling behind young people (M=3.1713), the lowest factor is loss of self- confidence to deal with physical, emotional, social aspects of life(M=2.6080). 4. The results from the test for the degree of powerlessness, according to the subject's demographic variables, showed that there were significant differences between age, sex, marital status, educational level, religion, possession of house, job, monthly pocket money, health status, illness and a place of residence.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2013년도 춘계학술대회 논문집
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• pp.1371-1372
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• 2013

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 추계학술대회 논문집
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• pp.551-554
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• 2005

This study is concerned about the design and structural analysis of high integrated tool tower ATC(Automatic Tool Changer) for machine tool. Recently, many studies have been undergoing to reduce a working time in a field of machine tool. Tool tower ATC belongs to reduce a stand-by time by shortening a tool exchanging time. The developed system can store more number of tool in small space than other machine. The analysis is carried out by CATIA V5 software. In the result of structural analysis, the safety factor of the developed system is confirmed.

• 한국기계가공학회지
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• 제11권1호
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• pp.13-19
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• 2012

In this study, ultrasonic vibration tool designed and made by using FEM analysis. And machining test was carried out in various machining conditions using ultrasonic vibration capable CNC machine. For work material, alumina ceramic ($Al_2O_3$) was used while for tool material diamond electroplated grinding wheel was used. To evaluate ultrasonic vibration effect, grinding test was performed with and without ultrasonic vibration in same machining condition. In ultrasonic mode, ultrasonic vibration of 20kHz was generated by HSK 63 ultrasonic actuator. The two grinding speeds, 1.67m/s and 3.35m/s, were applied. On the other hand, grinding forces were measured by KISTLER dynamometer.

• 소성∙가공
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• 제14권3호
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• pp.200-206
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• 2005

In general, a lot of small electrode is needed for making precision injection molds, such as cell phone mold and precision connector mold, because of the limitations of NC milling process. Those small electrodes usually have very simple shapes and the actual cutting time is so short, but many NC programs and set-up process, a very complicated and time consuming Job, are needed for each electrode. This paper deals the method for increasing the productivity of machining electrodes. In this work, the process standardization of machining electrode was done and special jig fer machining small electrodes was developed. Automatic tool path optimization software was also developed to minimize tool changing time. In addition, in-line cutting tool measuring system was adopted. The productivity of machining for small electrode has been increased up to $100\%$.

• 한국군사과학기술학회지
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• 제23권2호
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• pp.159-167
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• 2020

In actual battlefield environment, IFF radar plays an important role in distinguishing friend or foe targets and assigning unique identification code to management. Performance of IFF radar is greatly affected by radio environment including atmosphere and terrain, target maneuvering and operation mode. In this paper, M&S tool is consisted of interrogator(IFF radar) and answering machine(target) for radar performance analysis. The wave propagation model using APM(Advanced Propagation Model) and radar actuator system were modeled by considering beam waveform of individual operation beam mode. Using this tool, IFF radar performance was analyzed through two experimental results. As a result, it is expected that performance of IFF radar can be predicted in the operational environment by considering target maneuvering and operation beam mode.

• 한국CDE학회논문집
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• 제22권2호
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• pp.202-214
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• 2017

The augmented visualization of analysis results can play an import role as a post-processing tool for the modeling & simulation (M&S) technology. In particular, it is essential to develop such an M&S tool which can run on various multi-devices. This paper presents an augmented reality (AR) approach to visualizing and interacting with M&S post-processing results through mobile devices. The proposed approach imports M&S data, extracts analysis information, and converts the extracted information into the one used for AR-based visualization. Finally, the result can be displayed on the mobile device through an AR marker tracking and a shader-based realistic rendering. In particular, the proposed method can superimpose AR-based realistic scenes onto physical objects such as 3D printing-based physical prototypes in a seamless manner, which can provide more immersive visualization and natural interaction of M&S results than conventional VR or AR-based approaches. A user study has been performed to analyze the qualitative usability. Implementation results will also be given to show the advantage and effectiveness of the proposed approach.