• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2014.10a
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• pp.394-398
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• 2014

Steam leakage is one of the major issues for the structural fracture of pipes of nuclear power plants. Therefore a method to inspect a large area of piping systems quickly and accurately is needed. Recently, the research detecting the steam leakage by using camera image is introduced. However, this method has a disadvantage. If a camera oscillates, it cannot detect a steam leakage exactly. In this paper, the technique that reduces the error due to a camera shaking is proposed. To verify the proposed method, we have performed the experiments for the oil leakage experiments. The results show that the technique can calibrate the error due to camera shaking.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.24 no.10
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• pp.817-824
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• 2014

Accelerometer and laser vibrometers are widely used to measure vibration of structures like a building or piping. Recently, the research measuring vibration by using camera image is introduced. However, this method has a disadvantage. If camera moves by the vibration cannot measure the vibration displacement of structure. We proposed the enhanced technique for measuring vibration using camera. This paper took the experiment for correction of error due to camera shaking. We verified through an experiment. And the accuracy of the method measuring the vibration displacement by using the camera images was analyzed.

• Transactions of the Society of Information Storage Systems
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• v.5 no.1
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• pp.14-18
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• 2009

This paper proposed an optimal plate spring design for the optical image stabilizer in mobile phones. The voice-coil motor (VCM) with plate spring is the smallest, lowest-cost solution for auto focus on the market today and it is also the simplest to implement. The VCM is selected in this paper for auto focusing. However, the design process is complex due to the many design variables coupled to each other and some constraints of each directional motion caused by the characteristics of plate spring. Because of the complex formulation of the design objective, a plate spring design is proposed through the design of experiments to find the optimal design satisfying design constraints.

• 월간 기계설비
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• no.10 s.207
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• pp.71-79
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• 2007

창립 37주년을 맞이한 계룡건설(주)은 우수한 재무구조와 정도경영, 합리적인 내실경영, 효율적인 업무시스템을 바탕으로 매년 고속 성장을 지속해온 건설업체다. 계룡건설(주)은 '변화'와'혁신'을 바탕으로 시시각각 변화하는 시대의 흐름을 예견하며 경영방침을 새롭게 정립해 왔다. 그 결과 대한민국 사회가 외환위기로 고통받은 IMF시절에도 인력의 인위적인 감축이나 구조 조정 없이 흔들림 없는 성장을 지속하는 저력을 발휘했다. 또한 주택사업 브랜드인'리슈빌'(불어 RICHE +VILLE의 합성어 : 풍요로움이 시작되는 곳)을 통해 차별화된 주거공간을 소비자에게 제공함으로써 고객감동과 수익창출을 실현하는 안정적인 수익구조를 마련했다. 앞으로도 계룡건설(주)은 튼튼한 재무구조를 바탕으로 고객만족, 기술혁신, 친환경 건설을 실현, 시대변화에 적응하여 한 단계 더 도약하는 기업으로 거듭나고 있다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.9
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• pp.1468-1474
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• 2001

In this paper, a new fuzzy-logic anti-swing control scheme is proposed for a three-dimensional overhead crane. The proposed control consists of a position servo control and a fuzzy-logic control. The position servo control is used to control the trolley position and rope length, and the fuzzy-logic control is used to suppress load swing. The proposed control guarantees not only prompt suppression of load swing but also accurate control of trolley position and rope length for the simultaneous travel, traverse, and hoisting motions of the crane. The effectiveness of the proposed control is shown by experiments with a prototype three-dimensional overhead crane.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.9
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• pp.2399-2411
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• 1995

Crane operation for transporting heavy loads inherently causes swinging motion at the loads due to crane's acceleration or deceleration. This motion not only lowers the handling safety but also slows down the handling process. To complement such a problem, Korea Atomic Energy Research Institute(KAERI) has designed several anti-swing controllers using open loop and closed loop approaches. They are namely a pre-programmed feedback controller and a fuzzy controller. These controllers are implemented on a 1-ton crane system at KAERI and their control performances are compared. Test operations show that the new controllers are superior to that of conventional cranes in terms of robustness to the disturbances and adaptation capability to the change of rope length.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.3
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• pp.164-169
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• 2006

A systematic methodology has been proposed to establish a reliable design of water pump system. A simplified steady-state dynamic model of water pump system has been developed to study the response of water pump system to the dynamic load mainly due to the run-out and unbalance. Design modifications are needed to strengthen the structural integrity of existing designs. Increasing the natural frequency of system is pursued to prevent a resonance from occurring in the engine excitation range. A computational reliability methodology combined with finite element analysis is used to identify the most significant factor affecting the system performance. This method considered influence of design control parameters for the performance of design. By including control factors to the system model in a systematic way, more reliable design is expected.

• Journal of Institute of Control, Robotics and Systems
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• v.12 no.8
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• pp.810-817
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• 2006

This paper presents a rotational motion estimation and correction technique for digital image stabilization. An equivalent rotation model is derived so as to accommodate a combined rotational and the translational motion. Thanks to this simplification, the suggested estimation algorithm can directly find the rotational center using geometric characteristic of local motion vectors instead of using searching method. And we also present recursive version of frame to reference algorithm(FRA) for the real time implementation. The proposed DIS system does not require time consuming parameter searching process, while showing comparatively good performance compared with the previous ones. To show the effectiveness of the DIS scheme, the algorithm has been implemented on the DSP based hardware system and experimental results are also discussed.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.62 no.3
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• pp.407-413
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• 2013

This paper proposes anti-swing control of overhead crane system using sum of squares method. The dynamic equations of overhead crane include nonlinear terms, which are transformed into polynomials by using Taylor series expansion. Therefore the dynamic equation of overhead crane can be changed to the system of polynomial equation. On the basis of polynomial dynamics of crane system, we propose the Sum of Squares (SOS) conditions considering the input constraints. In addition, control gains are obtained by numerical tool which is called by SOSTOOL. The effectiveness of the proposed method is demonstrated by numerical simulation.

• The Safety technology
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• no.154
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• pp.18-19
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• 2010

(주)테크팩솔루션은 50년대 국내 최초로 유리병 산업에 진출한 이래 지금까지 국내 유리병 산업을 선도해 오고 있다. PET, 알루미늄 캔 등 액체제품 포장관련 해서는 명실공이 국내 최고로 인정받고 있는 종합포장재 회사인 것. 이런 (주)테크팩솔루션의 발전에는 경기도 이천 대월면에 위치한 이천공장의 역할이 컸다. 이곳은 1980년에 국내 최초로 알루미늄 투피스캔(two-piece con)을 생산하기 시작한 곳으로, 현재는 이를 통해 연간 600~700억원의 매출을 올리고 있다. 즉 (주)테크팩솔루션의 주력이다. 이처럼 이천공장이 우수한 성과를 내고 있는 비결이 무엇일까? 이에 대해 이곳 관계자들은 '안전'을 그 이유로 꼽는다. 철저한 안전관리로 재해가 없으니 기계가 멈출 일이 없고, 근로자의 공백이 생기는 일도 없다는 게 그 이유다. 다실 말해 안전성을 바탕으로 사업장이 흔들림 없이 꾸준한 성장을 거듭해 올 수 있었다는 것이다. 실로 이곳 안전관리자의 실력에 찬사가 나올만한 대목이다. 안전으로 회사의 매출증대까지 일궈내게 만든 (주)테크팩솔루션 이천공장의 김문선 차장을 만나 이야기를 나눠봤다.