• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.18 no.6
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• pp.664-674
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• 2009

This paper presents the theoretical development of a complete navigation problem of a non-holonomic mobile robot by using sonar sensors. To solve this problem, a new method to compute a fuzzy perception of the environment is presented, dealing with the uncertainties and imprecision from the sensory system and taking into account nonholonomic constraints of the robot. Fuzzy perception, fuzzy controller are applied, both in the design of each reactive behavior and solving the problem of behavior combination, to implement a fuzzy behavior-based control architecture. Different experiments in populated environments have proved to be very successful. Our method is able to guide the mobile robot named KUM-Robo safety and efficiently during long experimental time.

• Proceedings of the IEEK Conference
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• 2001.06e
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• pp.119-122
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• 2001

This paper deals with new type of active magnetic bearing (AMB) for the linear motors. We adopted optical sensing mechanism for the gap sensing. Using the laser and the PSD (Position Sensitive Device), the absolute rotor position is obtained independent of the profile of the guide rail. With this measurement, the rotor can be controller to follow the straight beam of the laser. Another advantage of optical sensing mechanism might be the elimination of the possible interference between the proximity sensor and the electro-magnet. By adopting the push-full actuating mechanism, the bearing stiffness is increased near the equilibrium position. For the simplicity, distributed control system is constructed. Eight independent PID control algorithm is used with the full order observer. Several simulation md test results are presented.

• Nuclear Engineering and Technology
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• v.38 no.7
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• pp.665-674
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• 2006

Three-dimensional neutron flux and fluence of Kori Unit 3 were evaluated using the synthesis technique described in Regulatory Guide 1.190 for all reactor geometry. For this purpose DORT neutron transport calculations from Cycle 1 to Cycle 15 were performed using BUGLE-96 cross-section library. The calculated flux and fluence were validated by comparing the calculated reaction rates to the measurement data from the dosimetry sensor set of the $5^{th}$ surveillance capsule withdrawn at the end of cycle 15 of Kori Unit 3. And then the best estimation of the neutron exposures for the reactor vessel beltline region was performed using the least square evaluation. These results can be used in the assessment of the state of embrittlement of Kori Unit 3 pressure vessel.

• Proceedings of the Korea Information Processing Society Conference
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• 2014.04a
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• pp.1034-1037
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• 2014

2013년도에 자전거 판매량이 100 만대를 돌파하면서 자전거 운동에 대한 사람들의 관심이 증가하고 있다. 뿐만 아니라, 서울시 등 각 지방 자치에서 자전거 도로를 설치하고 자전거 코스를 제공하는 등 국민의 건강관리에 힘쓰고 있다. 자전거를 통한 건강관리에 대한 관심이 증대되면서 스마트 디바이스를 활용한 운동 관련 어플리케이션도 역시 증가하고 있다. 본인의 기록을 측정하기 어렵고 별도의 장비가 필요하던 과거와 달리 이제는 누구나 가지고 있는 스마트폰만으로도 자신의 운동을 효율적으로 자신의 운동을 관리할 수 있도록 하는 어플리케이션이 인기를 끌고 있다. 이러한 수요에 맞추어 스마트 상의 GPS 센서를 이용한 자전거 가이드 시스템 '자전거로 달려볼까'는 별도의 센서를 부착할 필요 없이 스마트폰에 기본적으로 포함되어 있는 GPS 센서를 이용하여 사용자에게 운동 기록 측정, 기록 보기, 코스 및 날씨정보를 제공한다.

• Proceedings of the Korea Information Processing Society Conference
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• 2015.04a
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• pp.327-328
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• 2015

최근 건강을 생각하는 사람이 증가하면서 걷는 사람들이 증가하고 있다. 걷기를 통한 건강관리에 대한 관심이 증대되면서 스마트 디바이스를 활용한 운동 관련 어플리케이션도 역시 증가하고 있다. 본인의 기록을 측정하기 어렵고 별도의 장비가 필요하던 과거와 달리 이제는 누구나 가지고 있는 스마트폰만으로도 자신의 운동을 효율적으로 자신의 운동을 관리할 수 있도록 하는 어플리케이션이 인기를 끌고 있다. 이러한 수요에 맞추어 스마트 상의 GPS센서를 이용한 걸음 가이드 시스템 '걸어보자'는 별도의 센서를 부착할 필요 없이 스마트폰에 기본적으로 포함되어 있는 GPS센서를 이용하여 사용자에게 추천루트를 제공한다.

• International journal of advanced smart convergence
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• v.7 no.4
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• pp.169-173
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• 2018

Iris diagnosis based on the color and texture information is one of a novel approach which can represent the current state of a certain organ inside body or the health condition of a person. In analysis of the iris images, there are critical image artifacts which can prevent of use interpretation of the iris textures on images. Here, we developed the iris diagnosis system based on a hand-held typed imaging probe which consists of a single camera sensor module with 8M pixels, two pairs of 400~700 nm LED, and a guide beam. Two original images with different light noise pattern were successively acquired in turns, and the light noise-free image was finally reconstructed and demonstrated by the proposed artifact removal approach.

• IEMEK Journal of Embedded Systems and Applications
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• v.14 no.3
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• pp.151-156
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• 2019

According to recent advances in technology, major robot technologies that have been developed and commercialized for industrial use are being applied to various fields in our everyday life such as guide robots and cleaning robots. Among them, the navigation based on the self localization has become an essential element technology of the robot. In the case of indoor environment, many high-priced sensors are used, which makes it difficult to activate the robot industry. In this paper, we propose a robotic platform and a moving algorithm that can travel by using Dijkstra algorithm. The proposed system can find a short route to the destination with its own position. Also, its performance is discussed through the experimentation of an actual robot.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.12
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• pp.174-181
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• 2004

Ultra precision positioning mechanism has widely been used on semiconductor manufacturing equipments, optical spectrum analyzer and cell manipulations. Ultra precision positioning mechanism is consisted of several actuators, sensors, guides and control systems. Its efficiency depends on each performance of components. The object of this study is to design, analysis and manufacture all of the inchworm linear motor system, which is one of the equipments embodied in ultra precision positioning mechanism. Inchworm linear motor system is consisted of a controller system and an inchworm linear motor, and its driving form is similar to a motion of spanworm. A design and manufacture of inchworm linear motor, which is consisted of three PZT actuators, a rod, two columns and a guide plate, are performed. Minimizing the von-Mises stress of the hinge using Taguchi method and simulation by FEM software optimizes the structural design in a column of flexure hinge. The designed columns and guide plates are manufactured by a W-EDM and NC-milling. A controller system, which is an apparatus to drive inchworm linear motor, can easily adjust driving conditions by varying resonance frequency and input-output voltage of actuators and amplifiers. The performance of manufactured inchworm linear motor system is verified and valuated. In the future, inchworm linear motor system will be used to make a more precision positioning by reinforcing a sensor and feedback system.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.4
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• pp.1515-1522
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• 2011

This paper proposed the finite element analysis technique for improving the correleration accuracy between FEA and test on a pedestrian lower legform impact. Europe has been evaluating the bumper pedestrian impact by Euro-NCAP, and it will also be applied in a domestic area by K-NCAP in 2013. By using the compression test result of bending resisting stiffener, a pedestrian bumper modeling guide was presented by analayzing the force-displacement curve of stiffener. And by using the sensor measurement results in car pedestrian test, pedestrian impact behavior was analyzed between test and finite element analysis result. Finally, the finite element analysis guide for a pedestrian bumper impact was presented to improve the correleration accuracy.

• Safety and Health at Work
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• v.13 no.1
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• pp.40-50
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• 2022

Background: Underground mines have several hazards that could lead to serious consequences if they come into effect. Acquiring, evaluating, and using the real-time data from the atmospheric monitoring system and miner's positional information is crucial in deciding the best course of action. Methods: A graphical user interface-based software is developed that uses an AutoCAD-based mine map, real-time atmospheric monitoring system, and miners' positional information to guide on the shortest route to mine exit and other locations within the mine, including the refuge chamber. Several algorithms are implemented to enhance the visualization of the program and guide the miners through the shortest routes. The information relayed by the sensors and communicated by other personnel are collected, evaluated, and used by the program in proposing the best course of action. Results: The program was evaluated using two case studies involving rescue relating to elevated carbon monoxide levels and increased temperature simulating fire scenarios. The program proposed the shortest path from the miner's current location to the exit of the mine, nearest refuge chamber, and the phone location. The real-time sensor information relayed by all the sensors was collected in a comma-separated value file. Conclusion: This program presents an important tool that aggregates information relayed by sensors to propose the best rescue strategy. The visualization capability of the program allows the operator to observe all the information on a screen and monitor the rescue in real time. This program permits the incorporation of additional sensors and algorithms to further customize the tool.