• Proceedings of the KIEE Conference
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• 2005.07b
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• pp.1144-1146
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• 2005

This paper presents the optimal design reducing the rotor inertia in order to improve the driving characteristic of BLDCM for robots. The parallel Genetic Algorithm is performed to rotor inertia minimization in optimal design. Also, velocity profile with finite jerk method is introduced to reduce vibration of BLDCM. As a result, a torque characteristic is same although rotor inertia is reduced 2/3 compared with prototype model. And, maximum vibration value is reduced by 63.4[%1 according to apply finite jerk.

• Journal of Engineering Education Research
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• v.15 no.4
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• pp.94-100
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• 2012

The needs for enhancing creativity in engineering design education continue to increase. Recent studies about a learning environment and learning support tools provide some new possibilities. The education of creative thinking however must begin from the change of attitude of students to creativity. The experimental results and some lessons for modification of systematic engineering design methodology to creative were reported from the course 'engineering design'.

• Tribology and Lubricants
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• v.36 no.4
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• pp.215-231
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• 2020

The paper presents extensive survey and review of experimental and analytical researches on fluid film bearings and squeeze film dampers (SFDs) for turbomachinery available in open literature (major archival international journals) published recently (2018 and 2019 only). Over 60 published research works are reviewed based on the research topics and objectives, the types of bearings, size of bearings, and main design parameters with a brief summary of experiments and/or predictions in each work. Some important findings and general observations about the experimental and/or predictive data are also presented. There are several major trends observed throughout the survey. A large portion of the papers focuses on bearing surface textures and effect of operating and assembly conditions on static and/or dynamic forced performances, as well as bearing surface roughness and wear patterns. Researches on geometry of orifices and recesses in hydrostatic (or hybrid) bearings, as well as bearing system stability predictions using thermohydrodynamic analysis and computational fluid dynamics (CFD), are considered as significant topics. Studies on SFDs mainly focus on experimental identification of force coefficients for various SFD geometries and sealing conditions. Reliable experiments of fluid film bearings and SFDs along with the development of experimentally benchmarked predictive tools enable reinforcement of the path for reliable implementations of the bearing components into high performance rotating machinery operating at extreme and harsh conditions. The extensive list of sources of recent experiments in the available open literature is a welcome addition to the analytical community to gauge the accuracy of predictive tools.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.1
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• pp.83-88
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• 2015

At the early stages of engineering design, a number of design concepts may be suggested. With a great degree of freedom, making a good choice may be a challenge at this stage. In this study, a simplified evaluation criterion for design concepts is presented based on cost, simplicity and safety. Cost is estimated by the amount of materials and the required level of tolerance. Simplicity is represented by the number of parts, assembly steps, and fasteners. Safety is assessed by the level of potential failure. The proposed criterion is applied to an example design of driving mechanisms for cervical vertebrae massage machine.

• Journal of Power System Engineering
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• v.22 no.1
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• pp.5-10
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• 2018

In order to employ factorial design on electronically-controlled diesel engine, effects of 5 factors on specific fuel consumption, nitrogen oxides and carbon monoxide were examined by fractional and full factorial design in this research. There were different results between fractional and full factorial design, then effect of variables as ambient condition and measurement of fuel consumption were confirmed. It was shown that ambient condition affected uniformly trend of nitrogen oxides and carbon monoxide. However, both ambient condition and measurement of fuel consumption had nothing to do with trend of specific fuel consumption and therefore it must be careful to employ factorial design on specific fuel consumption as response.

• 한국가스학회:학술대회논문집
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• 2004.11a
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• pp.164-172
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• 2004

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.4
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• pp.1333-1346
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• 1996

As the automation system in manufacturing field works more efficientely, the automation scheme is applied to many areas. In order to reduce the entire manufacturing, cost the design process must be automated. However, design process is so complicated, it is very difficult to construct the design automation system. The axiomatic approach to design provides a general theoretical framework for all design fields, including mechanical design. The key concepts of axiomatic design are : the existence of domains, the characteristic vectors within the domains that can be decomposed into hierarchies through zigzagging between the domains, and the design axioms. Using this approach, the glass bulb design process was analyzed and the design automation software was developed. Through menu display, a user can select or furnish the design input and generate the drawing with ease.

• 한국가스학회:학술대회논문집
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• 2004.11a
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• pp.153-157
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• 2004

• 한국가스학회:학술대회논문집
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• 2006.11a
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• pp.81-89
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• 2006

• 한국가스학회:학술대회논문집
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• 2001.10a
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• pp.114-121
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• 2001