• Journal of Intelligence and Information Systems
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• v.3 no.1
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• pp.13-30
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• 1997

인공지능 분야 중 하나의 전문시스템 기술은 현재 산업현장에서 여러 가지 분야의 문제 해결에 이용되고 있다. 본 논문은 공압설계를 자동화하기 위한 전문가시스템 PDES(Pneumatic Design Expert System)의 프로토타입 개발에 관한 것이다. 공압설계를 위한 요구 조건이 시스템의 입력정보로 제공되면 공압설계 시방과 공압회로도, 공압작업요소의 영상이 시스템의 출력으로 제시된다. PDES의 지식 베이스는 산업분야 전문가의 전문지식과 경험적 지식을 획득, 분석하여 전문가 시스템 쉘을 이용하여 구성하였으며 추론전략으로는 전향추론을 적용한 규칙기반추론(Rule-Based Reasoning)을 이용하였다. PDES는 공압설계시 설계 업무를 자동화 하여 능률을 향상시켜 줄 뿐만 아니라 공압 관련 비전문가가 공압설계를 할 때에는 큰도움을 줄 수 있다.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.731-736
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• 2011

A pneumatic driving solenoid valve operates pneumatic control devices by opening/closing operating flow passage when the command is given by control system for the liquid-propellant feeding system of space launch vehicle. The simulation model of pneumatic driving solenoid valve is designed with AMESim to verify the designs and evaluate the dynamic characteristics and pneumatic behaviors of valve. To validate a valve simulation model, the simulation results of their operating durations of valve by AMESim analysis are compared with the results of experiments. In addition, the results of internal flow simulation with FLUENT are utilized to improve the accuracy of valve-modeling. Using the model, we analyze performance of valve; opening/closing pressure, operating time on various design factors; shape of control valve seat, drainage seat, rate of sealing diameter, volume of control cavity. This study will serve as one of reference guides to enhance the developmental efficiency of ventilation-relief valves with the various operating conditions, which shall be used in Korea Space Launch Vehicle-II.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.12
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• pp.1541-1546
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• 2013

The stress concentration of lock-claws, which are one of the important parts for pneumatic fitting for a flexible tube connection, was investigated by finite element simulation. In this study, the generation of the local plastic deformation was predicted when the tube was hooked up to a pneumatic fitting in order to disperse the stress concentration, and design optimization was carried out using the Taguchi method. For the optimization, the outer width, bending angle, and inner radius of the lock-claws are used as main variables. As a result, their respective contribution ratios are revealed as 81.3%, 10.9%, and 1.5%. The ratio of the total stress distribution was improved by 4% compared with the initial design of the lock-claws.

• Proceedings of the KIPE Conference
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• 2014.11a
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• pp.171-172
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• 2014

조선해양 생산현장에서는 생산 용도로 다양한 에너지원을 사용하고 있지만 가장 많이 사용하는 에너지원은 전기이며, 전기의 30% 이상을 압축공기 생산에 사용하고 있다. 압축공기를 동력으로 이용하는 경우, 특히 그라인더에서는, 에너지 변환 효율이 전력대비 1/4~1/5 수준으로 매우 낮다. 본 연구에서는 공압 그라인더를 BLDC 모터 전동 그라인더로 대체하기 위한 연구를 수행하였다. 그 결과 7인치 공압 그라인더와 대등한 출력을 내면서 안전성과 내구성 면에서 우수한 상용급 전동 그라인더 시제품을 설계 및 개발하였다. 또한 시제품에 대한 현장 시험을 거쳐 다양한 개선방안과 설계개선안을 통해 향후 상용급 BLDC모터 전동 그라인더 개발을 위한 설계기술을 확보할 수 있었다.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1992.10a
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• pp.255-259
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• 1992

최근 산업계에서 일고 있는 저투자성 자동화 시스템분야의 활성화에 따라 자동화 핵심 기기인 핵심공압 부품의 수요가 날로 증가하고 있다. 특히 산업계의 생산비 절감, 전자화 추세에 따라 공압 AC솔레노이드 밸브는 핵심공압 부품 중에서 매우 중요한 위치를 차지하게 되었다. 본 연구에서는 AC 솔레노이드의 작동시 발생되는 동적특성 절환메카니즘의 동적특성을 실험적으로 측정. 분석하였으며, 그 결과로부터 AC 솔레노이드 최적설계 해석 기초를 확립코자 본 연구를 수행하였다.

• Journal of Practical Engineering Education
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• v.12 no.1
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• pp.1-10
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• 2020

The pneumatic control circuit is an important basic element that constitutes factory automation in the era of the 4th Industrial Revolution, and the ability to design and fabricate pneumatic control circuit at the university level is one of the most important educational courses. In this study, it introduced collaborative learning by group, and capstone design technique applied to the subject of design and fabricate of pneumatic control circuit. In addition, it intends to contribute to the innovation of practical engineering education by examining the learning achievement of students. It was investigated analytical skill differences by applying cooperative learning to the experimental group and by applying traditional lecture methods to the comparison group. The experimental group that conducted cooperative learning showed higher academic ability than the comparison group that conducted only traditional lectures, and the t-test results of the significant level p<0.05 also confirmed that there were significant differences between the two groups. It was also responded 13 survey questions in four experimental groups and analyzed the results, showing a high satisfaction level of 4.731 on average. Through this study the design and fabrication of the pneumatic control circuit is more effective in improving students' learning achievement when applying the capstone design technique than when operating as a normal subject and expected to use as a basic material for the development of the curriculum of Capstone design in the future.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.1 s.118
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• pp.72-79
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• 2007

As environmental vibration requirements on precision equipment become more stringent, use of pneumatic isolators has become more popular and their performance is subsequently required to be further improved. Dynamic performance of passive pneumatic isolators is related to various design parameters in a complicated manner and, hence, is very limited especially in low frequency range by volume of chambers. In this study, an active control technique, so called time delay control which is considered to be adequate for a low frequency or nonlinear system, is applied to a single chamber pneumatic isolator. The procedure of applying the tine delay control law to the pneumatic isolator is presented and its effectiveness in enhancement of transmissibility performance is shown based on simulation and experiment. Comparison between passive and active pneumatic isolators is also presented.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2010.05a
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• pp.101-104
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• 2010

A bulkhead-type pulse separation device has been developed for the multi-pulse rocket motor. The design parameters of the pulse separation device were the shape of the rupture disc slit, welding conditions, and the implementation of the seal disc. The pneumatic tests of the fabricated pulse separation devices showed that the rupture pressure increased as the quantity of the rupture disc slit and welding strength increased and the seal disc was implemented.

• ICROS
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• v.5 no.2
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• pp.7-16
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• 1999

• Journal of the Korea Academia-Industrial cooperation Society
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• v.3 no.4
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• pp.280-284
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• 2002

This paper presents computer simulations of the stacking and transferring system for the fast freeform fabrication system. The stacking and transferring system is essential for the fast freeform fabrication system and its stable motion is very important for consistent stacking of the cut slices. The stacking and transferring system can be modeled as a pneumatic system. The system consists of air compressor, the control valve, and the cylinder. The governing parameters have been changed and the simulation results are shown to predict the time response of the system. The results show some parameters should be correctly tuned to obtain stable system response.