• 한국공작기계학회논문집
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• 제15권3호
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• pp.1-7
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• 2006

By the reason of increased demand of high productivity, the researches on manufacturing process and equipments for reducing cycle time have been made in many directions of a machine tool industries. Especially high productivity is very important to machining center with high-speed spindle. This paper proposed method of reducing T-T(tool to tool) time which results in shorter unclamping time. T-T time varies as factors such as a hydraulic system, a drawbar mass, a flow meter, a disc spring, piston and pipe diameters. In this paper We could find design factors has much influence on decreasing the unclamping time using DOE(Design of Experiment) and optimized the level of the factors using AMESim $4.0^{(R)}$ and visualNastran $4D^{(R)}$ Finally, we have verified improved result of the optimized factors with initial design.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1745-1748
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• 2005

According to the demand of the high productivity, the interest of manufacturing skills is growing in industrial society. Especially the high speed spindle in machining center becomes important these days. The exchange time of the tool in machining center usually calls T-T(tool to tool) time. Detailly explaning, It is influenced by the unclamping time. Affecting factors of the unclamping time are various(the hydraulic system, drawbar mass, a flow meter, disc spring, a piston diameter, pipe diameters, and so on). In this study, we could find factors that decrease the unclamping time and verify it for softwares.(AMESim $4.0^{(R)}$ & visual Nastran $4D^{(R)}$)

• 한국정보통신학회논문지
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• 제23권10호
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• pp.1216-1227
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• 2019

본 논문에서는 IoT 서비스 개발 과정에서 효율적인 IoT 애플리케이션 테스팅이 가능하도록 지원하는 도구인 TITAN(Tool for IoT ApplicatioN testing)을 제안한다. TITAN은 IoT 서비스 개발자가 개발 중인 애플리케이션 로직을 테스팅 하는 데 필요한 물리적 환경 및 사용자 행동에 제약받지 않고, 개발 환경에서 애플리케이션 실행 및 확인이 가능하도록 고안되었다. 개발자는 TITAN을 이용하여 개발 과정에서 반복적인 테스팅에 소모되는 시간과 노력을 줄일 수 있을 것이다. 본 논문에서는 TITAN의 시스템 아키텍처와 현재까지 구현된 프로토타입을 제시한다. 또한 소규모 유저 스터디를 통해 TITAN의 유용성과 사용성을 평가한다. 유저 스터디 참가자들은 TITAN의 유용성에 대해 긍정적으로 생각하였다. 마지막으로 현재 연구의 한계와 향후 연구 방향에 대해서 논의한다.

• 중환자간호학회지
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• 제11권3호
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• pp.12-22
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• 2018

Purpose : This methodological study develops an oral health assessment tool for critically ill patients. Method : From February 15 to April 30, 2014, this study was conducted to test the validity and reliability of the tool at two general hospitals and three medical and surgical intensive care units (ICUs) in Seoul, Korea. Results : The result of the intraclass correlation coefficient to test the between-observer reliability by analyzing the oral health assessment scores before and after oral nursing care showed that .93 of before oral care and .90 of after oral care. The correlation coefficient values of .68 (p<.001) and .71 (p<.001) before and after providing oral nursing care, respectively, indicated the presence of a statistically significant correlation between the tool and the criterion. Using the paired t-test, the differentiated validity of the tool was tested in patients who had developed pneumonia after entering the ICU. A statistically significant difference in scores was found between the time of entering the ICU and that of developing pneumonia (t=-8.73, p<.001), which provided evidence for the differentiated validity of the tool. Conclusions : Since the validity and reliability of the tool developed in this study were verified, this tool can be used to assess the oral health conditions of critically ill patients.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.16-21
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• 2002

The high speed machining center(HMC) has been widely applied to manufacture a die and trial product in many machine industry. Because the evaluation fer the HMC is not sufficiently performed and the efficient cutting conditions aren't selected, a great loss has been caused in the cost aspect. In this study, the need of preliminary running time and unstable spindle speed is presented from the analysis of acceleration in idling. The Machinability fur the TiAlN coated flat end mill and STD11( $H_{R}$C60) is evaluated from the trends of tool wear and cutting force according to cutting conditions and slenderness ratio and a low response of tool dynamometer in high speed is proved. The resonance spindle speed is identified through the tool wear and natural frequency test.t.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2001년도 춘계학술대회
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• pp.189-193
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• 2001

This paper analyses the tool switching problem in the dynamic environment, where parts to be processed on a flexible machine arrive randomly. As the total number of tools required to Process a set of parts on the machine is generally larger than the available magazine storage capacity, tool switches between parts are usually necessary. We assume that tool switching must be made just before the processing of the parts. Since the time required for tool switches can be significant relative to processing time and cause the processing of parts to be delayed, it is desirable to minimize the number of tool switches. Therefore, we present one heuristic algorithm to minimize the total number of tool switches and the t)reposed heuristic is compared with the KTNS (Keep Tool Needed Soonest) policy on randomly generated problems.

• 한국산학기술학회논문지
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• 제13권2호
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• pp.685-693
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• 2012

본 연구는 노인요양시설의 노인 연하곤란 조기 발견 및 중재를 목적으로 연하곤란 사정도구를 개발하고 개발된 사정도구를 중심으로 제작된 중재프로그램 적용 효과를 평가하기 위해 실시하였다. 연구대상은 사정도구의 동시타당도 및 신뢰도 검증을 위해 노인요양시설 9곳에 근무하는 간호사 18명을 편의추출하였으며 중재 프로그램 효과 검정을 위해 노인요양시설 4곳의 입소자 50명을 대상자로 선정하여 실시하였다. 연구 결과 연하곤란 사정도구와 중재프로그램 적용 후 실험군의 체중은 증가하였으며(t=4.913, p=.000), 연하 총 시간은 감소하였다(t= -4.557, p=.000). 따라서 본 연구에서 도출된 연하곤란 사정도구와 중재프로그램을 노인요양시설에 적용한다면 노인의 삶의 질 증진과 흡인성 폐렴, 질식과 같은 응급 상황은 감소할 것이다.

• 한국컴퓨터정보학회논문지
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• 제20권9호
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• pp.97-104
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• 2015

Recently, the need for real-time systems which are providing various types of information that occur in large quantities in IoT environment is increasing. In this paper, we propose a middleware system which can monitor in real time on a web environment. The proposed system is designed to be integrated by using communication functions provided by a network operating system and external sensors. The proposed system is compared with an existing system and analysed by the server performance testing tool.

• 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 $100\%$.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 1997년도 추계학술대회 논문집
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• pp.48-53
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• 1997

The objective of this paper is to present the development and application of interface software between robot and F/T sensor for force control. The interface software for among the robot controller, F/T sensor, and host PC is based on interrupt-driven method. To show the suitability of developed interface software, writing-task is performed in real time using F/T sensor that mounts on the wrist of the robot and Scara type 4-axis robot.