• Journal of the Korean Society of Propulsion Engineers
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• v.21 no.1
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• pp.26-35
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• 2017

The high-cycle fatigue cracking and the resonance generated in operation of a centrifugal compressor are main cause of the impeller damage. In order to prevent the damage, the impeller is designed or modified to have sufficient strength to withstand the operating condition. The damage prevent design will lead to a change of the flow condition and the performance characteristics of the compressor. In this study, the computational analysis were performed to identify the flow and the performance characteristics. The cases are a scalloped and a increased the blade thickness models with a closed type impeller. As the analysis results, the value of head coefficient and total to total efficiency for the increased the blade thickness model was decreased by each 0.5% and 0.1% than the values of the baseline model. Each value for the scalloped model was increased by 0.4% and was decreased by 1.6%.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.10a
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• pp.219-220
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• 2009

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1369-1370
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• 2013

• Proceedings of the KIEE Conference
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• 2006.07d
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• pp.1927-1928
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• 2006

본 논문에서는 카오스 로봇을 제작하기 방법을 제시하고 그 결과를 나타내었다. 카오스 로봇을 제작하기 위하여 가속도 센서를 설계하고 곡선 주행이 가능하며 장애물을 회피하기 위한 알고리즘을 제시하였다.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2012.04a
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• pp.881-882
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• 2012

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.04a
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• pp.327-328
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• 2011

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2011.10a
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• pp.50-51
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• 2011

• Information and Communications Magazine
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• v.26 no.4
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• pp.46-54
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• 2009

최근, 차량간 통신 기술의 적용을 통해 운전자의 안전성 강화를 목적으로 하는 능동형 차량 안전서비스 실현을 위한 연구가 활발히 진행되고 있다. 이러한 서비스의 범주에는 충돌사고 경고 및 회피, 도로상의 위험요소 경고, 교통 안전정보 제공 등이 포함된다. 본 고에서는 통신 시스템 설계 관점에서 차량 안전서비스 실현을 위한 기술 요소, 통신 프로토콜 설계 및 개발 방법론에 대하여 논하고자 한다.

• Journal of the Korean Institute of Intelligent Systems
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• v.19 no.4
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• pp.470-477
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• 2009

Modular reconfigurable robots with physical docking capability easily adapt to a new environment and many studies are necessary for the modular robots. In this paper, we propose a vision-based fuzzy autonomous docking controller for the modular docking robots. A modular docking robot platform which performs real-time image processing is designed and color-based object recognition method is implemented on the embedded system. The docking robot can navigate to a subgoal near a target robot while avoiding obstacles. Both a fuzzy obstacle avoidance controller and a fuzzy navigation controller for subgoal tracking are designed. We propose an autonomous docking controller using the fuzzy obstacle avoidance and navigation controllers, absolute distance information and direction informations of robots from PSD sensors and a compass sensor. We verify the proposed docking control method by docking experiments of the developed modular robots in the various environments with different distances and directions between robots.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.23 no.12
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• pp.1700-1709
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• 2019

Recently, many researches have been under way to develop systems (services) to support the safety navigation of ships, and in these studies, common difficulties have been encountered in assessing the usefulness and effectiveness of the developed system. To solve these problems, we propose the DEVS-based ship navigation modeling and simulation technique. Following the preceding study, we analyze the COLREG rules and reflected to officer and helmsman agent models for decision making. Also we propose estimation and interpolation techniques to adopt the motion characteristics of the actual vessel to simulation. In addition, we implement the navigation simulation system to reflect the designed proposed methods, and we present five-scenarios to verify the developed simulation system. And we conduct simulations according to each scenario and the results were reconstructed. The simulation results confirm that the components modelled in each scenario enable to operate according to the navigation relationships.