• 대한기계학회논문집
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• 제19권3호
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• pp.868-876
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• 1995

This study deals with a position control of an electro-hydraulic servo system which consist of cylinder and high speed on-off valves operated by microcomputer. The merits of PWM control of hydraulic equipment are the robustness of the high spee on-off valve, its low price and the direct control without D/A converter. In the PWM control of high speed on-off valve, the time lag and switching time existing between the input and output signals of valve are considered as demerit points. To get analytical results, the effects of these demerits have to be clarified in detail. The object of this study is to propose a mathematical model for the behavior of high speed on-off valve and to get analytical results of this system. The dynamic characteristics of this system is examined by digital computer simulation analytically and compared with experimental results to varify the proposed mathematical model.

• 유공압시스템학회논문집
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• 제4권2호
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• pp.28-33
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• 2007

In the power plant facility which use soft coal as a power source the fan pitch blade control hydraulic actuator is used to control the inlet and outlet gas to regulate the internal pressure of the furnace and control the frequence. Sometimes malfunctions of this equipment lead to the decline of boiler thermal efficiency and unexpected power plant trip. In order to localize the fan pitch blade control hydraulic actuator specially for the 500MW large scale boiler, Analysis and modelling of the system is carried out mathematically. The responses of the system are examined by using matlab simulation fur the variation of the major parameters in view of reverse engineering. Consequently the validity of the established parameters are examined.

• 한국항행학회논문지
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• 제12권2호
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• pp.91-99
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• 2008

본 논문에서는 글로벌스타 위성 모뎀을 이용한 무선 원격제어 및 감시 시스템을 구축하였다. 시스템은 C8051F023 마이크로컨트롤러를 이용한 글로벌스타 위성 시스템 단말장비와 WGIS(Web-based GIS)를 이용한 사용자 프로그램으로 구성된다. 이를 통해서 단말장비와 사용자 프로그램 사이의 무선 원격제어 및 감시를 실험하였다. 사용자는 WGIS 프로그램를 사용한 Main 및 Control 다이얼로그를 통하여 용이하게 단말장비를 제어 및 감시 할 수 있으며 또한 위치정보를 확인 할 수 있었다. 단말장비 및 사용자 프로그램의 데이터 통신을 위해서 글로벌스타 위성 모뎀을 위한 PPP 및 TCP/IP 프로토콜을 구현하여 데이터 통신을 원활하게 수행할 수 있도록 하였다. GIS(Geographic Information System) 도구는 ESRI사의 ArcView와 MapObject로 구성되며 GIS를 통하여 사용자에게 시각적으로 다양한 정보를 제공할 수 있었다.

• 한국재난정보학회 논문집
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• 제18권4호
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• pp.699-705
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• 2022

연구목적: 시퀀스제어는 제조, 유통, 건설, 의료 산업분야의 자동화 등에 응용되어 널리 사용하고 있다. 4차산업의 발전으로 제어분야에 인공지능 융합 기술이 산업에 중요한 요소가 되어가고 있다. 특히 기존 시스템에 마이크로프로세서와 인공지능이 융합된 설비의 안전성과 혁신성을 평가하고 신뢰성 높은 장비개발이 요구되고 있어 교육목적의 장비를 개발하여 해당분야의 발전을 견인하고자 한다. 연구방법: 자체 개발한 일체형 인공지능 컨트롤러 모듈은 기존의 시퀀스 및 PLC제어 회로에 인공지능 능력을 융합한 장비이다. 본 장비의 성능평가항목으로 동작, 음성, 문자, 색상 등의 인식 능력과 회로의 안정성, 신뢰성을 평가하였다. 결론: 시퀀스 및 PLC 회로를 설계 후 융합된 일체형 인공지능 컨트롤러 모듈의 성능평가항목이 모두 만족하였고 회로의 안전성과 신뢰성에 문제가 없는 것으로 나타났다.

• 한국치위생학회지
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• 제10권5호
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• pp.935-945
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• 2010

Objectives : The purpose of this study was to examine the knowledge of dental hygienists on infection control in dental office and their attitude toward that in a bid to provide some information on ways of enhancing the level of infection control in dental office. Methods : The subjects in this study were 220 dental hygienists who worked in dental hospitals and clinics in Busan and South Gyeongsang Province. A survey was conducted from May 17 to June 17, 2010, and the answer sheets from 183 respondents were analyzed with a SPSS WIN 12.0 program. Statistical data on frequency, percentage and mean were obtained, and t-test, Pearson correlation coefficient and one-way ANOVA were utilized. Results : They got a mean of $4.59{\pm}.68$ in six categories of infection control knowledge. They had the best knowledge on dental waste disposal, followed by hand washing, post-sterilization management, instrument disinfection and sterilization, surface management of dental equipment and wearing personal protective equipment. They got a mean of $3.99{\pm}.54$ in attitude, and they scored lowest in practice of surface management of dental equipment. Overall, they scored higher in every aspect of knowledge than in attitude(t=11.410, p=.0.000). There was the greatest gap between their knowledge and practice in surface management of dental equipment (t=13.885, p=0.000), and there was the smallest gap between their knowledge and practice in hand washing(t=5.460, p=0.000). And a positive correlation was found between knowledge and attitude, as better knowledge of infection control led to better attitude toward that(p<.001). Finally, concerning infection control knowledge and attitude by general characteristics, the presence or absence of infection control guidelines made differences to infection control knowledge, and infection control attitude was statistically significantly different according to infection control education experiences(t=6.501, p=.012) and the presence or absence of infection control guidelines(t=22.836, p=.000). Conclusions : In order to bolster infection control in dental office, the related system should be improved to legally require dental personnels to implement infection control. Every dental office must be furnished with infection control guidelines, and sustained education should be provided for dental hygienists to carry out infection control.

• 드라이브 ㆍ 컨트롤
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• 제6권3호
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• pp.18-27
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• 2009

• 드라이브 ㆍ 컨트롤
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• 제4권1호
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• pp.9-15
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• 2007

• 드라이브 ㆍ 컨트롤
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• 제12권4호
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• pp.105-111
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• 2015

• 드라이브 ㆍ 컨트롤
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• 제11권1호
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• pp.54-58
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• 2014

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2004년도 하계학술발표 논문집
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• pp.203-203
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• 2004