• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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• pp.727-730
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• 2002

Most of battery industries are growing explosively as a core strategy industry for the development of the semi-conductor, the LCD, and the mobile communication device. Dynamic characteristic analysis consists of dynamic behavior analysis and finite element analysis and is necessary for effective design of machines. In the dynamic behavior analysis, the displacement, velocity, applied force and angular velocity of each components are simulated according to each part. In the FEA, stress analysis, mode analysis, and frequency analysis are performed far each part. The results of these simulations are used for the design specification investigation and compensation for optimal design of cell manufacturing line. Virtual Engineering of the separator inserting machine on the automatic cell assembly line systems are modeled and simulated. 3D motion behavior is visualized under real-operating condition on the computer window. Virtual Prototype make it possible to save time by identifying design problems early in development, cut cost by reducing making hardware prototype, and improve quality by quickly optimizing full-system performance. As the first step of CAE which integrates design, dynamic modeling using ADAMS and FEM analysis using NASTRAN are developed.

• 한국산학기술학회논문지
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• 제7권3호
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• pp.308-313
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• 2006

포탄의 탄착점은 대포의 형상, 제작공차, 제어시스템 그리고 발사체의 제작공차 등 여러 변수의 함수이다. 본 논문에서는 포탄의 탄두를 본체와 분리, 움직임이 가능한 형태로 부착하여 탄착점의 정확도를 향상시키는 가능성에 대하여 검토하였다. 기존의 포탄이 갖는 6 개의 자유도에 탄두의 3 개의 자유도를 더한 9 자유도의 동역학 식을 유도하였고 시뮬레이션을 통하여 가변탄두를 갖는 발사체가 탄두부분의 피치(pitch)와 요(yaw) 회전운동을 통하여 발사 초기의 불확실성을 흡수할 수 있음을 확인하였다.

• 대한기계학회논문집A
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• 제33권10호
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• pp.1045-1053
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• 2009

Precision stages for 6-DOF positioning, actuated by PZT stacks, which are fed back by gap sensors and guided by flexure hinges, have enlarged their application territory in micro/nano manufacturing and measurement area. The precision stages inherently have such limitations as the nonlinearity between input and output in piezoelectric stacks, feedback signal noise in precision capacitive gap sensors and low material damping in precision kinematic linkages of mechanical flexures. To surmount these limitations, the precision stage is modeled with physics-based variables, which are identified by transient response correspondence, and a gain margin calculation algorithm using the Prandtl-Ishlinskii model and describing function is newly developed to assess system performance more precisely than linear controller design schemes. Based on such analyses, a precision positioning controller is designed. Excellent positioning accuracy with rapid settlement accomplished by the controller is shown in step responses of the closed-loop system.

• 한국공작기계학회:학술대회논문집
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• 한국공작기계학회 2001년도 추계학술대회(한국공작기계학회)
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• pp.68-74
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• 2001

This system is composed of fine and coarse apparatus, measurement system and control system. Piezoelectric actuator is designed for fine positioning. We make a study of precision apparatus that is used in the various industrial machine. The study was carried out to develope a precision positioning apparatus, consisting of servo motor and piezoelectric actuator. Coarse positioning using lead screw is drived by servo motor. Control system output a signal from laser interferometer to amplifier of servo motor and piezoelectric actuator after digital signal processing(DSP). Resolution of this apparatus measure with laser interferometer. In this study, design method and control system with ultra precision position apparatus are researched. As the first step, we have estimated for control performance and system stability before an actual apparatus is manufactured by MATLAB with SIMULINK including various functions those are composed of pre-design and system modeling.

• 한국정밀공학회지
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• 제33권3호
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• pp.199-205
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• 2016

A thin sheet of metal with corrugated structures has been utilized in various devices: heat exchangers, separators in fuel cells, and many others. However, it is not easy to fabricate thin corrugated structures using a single-step stamping process due to their geometrical complexity. To solve this problem, firstly, a plate type heat exchanger was redesigned to attain the optimal value of aspect ratio and the optimal shape of corrugated structures for the actual loading conditions. A forming analysis of the corrugated plate was then carried out to determine the process parameters. From this work, the optimal value of aspect ratio was found to be 4.6. In addition, the process parameters of heat exchanger forming were optimized using the optimal value of aspect ratio, and the analytical results were evaluated through experiments. The results obtained indicated good agreements between them.

• 정보관리학회지
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• 제24권1호
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• pp.5-29
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• 2007

도서관과 정보센터를 둘러싼 환경적인 변화와 함께, 다양한 관리 기법을 개발하고 이를 도서관 업무와 서비스에 적용시켜야 할 필요가 있다. 본 연구에서는 이러한 관점하에서 새로운 경영 및 품질개선 기법으로서 6시그마를 도서관에 적용한 사례연구를 수행하였다. 특히 본 연구에는 6시그마 기법을 도서관에서 해외 학술정보를 입수하는 과정에 실제 적용하여 나타나는 문제점과 이를 해결할 수 있는 방안을 제시하는 것을 목표로 하였다. 이를 위하여 제조업 분야에서 주로 적용되었던 6시그마 기법의 하나인 DMAIC 방법을 이용하였다. 결과적으로 6시그마 기법을 본 연구에서 목표하는 분야에 있어서 높은 개선 효과를 거둘 수 있었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2005년도 제25회 추계학술대회논문집
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• pp.229-232
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• 2005

인화점이 높은 합성 액체연료인 RJ-4의 제조공정 개선에 관한 연구를 수행하였다. 상용원료인 MCPD(Methylcyclopentadiene dimer)를 이용한 RJ-4 연료제조에서 헤테로폴리 텅스토인산 세슘염 촉매와 2단 열 조절반응기를 사용하여 1차, 2차 수소화 및 이성화반응이 1 단계 연속공정으로 가능함을 알 수 있었다. 또한 $AlCl_3$ 대신에 헤테로폴리산 세슘염을 이성화촉매로 사용시 exe-THDMCPD(Tetrahydrodimethylcyclopentadiene)을 얻는 속도가 더 빠르며, 생성물과의 분리가 용이하고, 폐산 발생이 없으므로 환경친화적인 공정임을 확인하였다.

• 한국응용과학기술학회지
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• 제30권4호
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• pp.740-753
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• 2013

It is valuable research area regarding to developing manufacturing process of biogas from organic wastes take a side view of alternative for fossil energy and to improve the environmental atmosphere leads to decrease the greenhouse gas be discharged. The regulation which is prepared by environmental department shows that biogas as a transportation fuel is required to purity of above 95%, while it of natural gas is above 88%. However, in this situation it is necessary to prepare the regulation which is distributed by department of transportation as for the fuel be connected to vehicles as well in order to take step forward, and it is suggest to develop the technics of biogas this country's own original one, not be the technics imported from foreign countries, and also to turn to higher practical use of biogas for transportation area, since it shows far much less ratio have compared to other application areas.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2006년도 제27회 추계학술대회논문집
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• pp.169-174
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• 2006

본 연구는 재생냉각형 고압 축소형 연소기 설계에 관한 것으로 이 연소기를 제작하기 전에 열유속측정을 위한 물냉각 고압 축소형 연소기를 제작하였다. 물냉각 고압 축소형 연소기의 연소시험결과 높은 연소성능 및 냉각성능이 검증된 설계 조건을 얻었고 이를 바탕으로 재생냉각형 고압 축소형 연소기의 형상을 설계하였다. 설계된 연소기의 형상은 제작이 완료된 후 연소시험을 수행하여 실용성을 검증 할 예정이다.

• 한국환경보건학회지
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• 제37권1호
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• pp.57-63
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• 2011

Crocidolite quality control (QC) sampling created by the wet generation method has been validated by validation tests such as the accuracy, precision, and storage tests. For this study we designed and developed a manufacturing apparatus and standard operating procedure for making these QC samples. The most important step in the procedure of making QC samples was the stage eliminating static electricity in asbestos fibers. This static electricity hampers the fibers clog functioning. In accuracy and precision tests by phase contrast microscopy analysis, the difference between the reference values and the studied values was at maximum 17.8%. This satisfies the AIHA proficiency analytical test criteria for asbestos. We could confirm the nearly even distribution of crocidolite fibers on the membrane filter. Also, there was no loss of fibers in the storage test after the one month.