• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.433-437
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• 2003

Quantitative Feedback Theory (QFT) is one of effective methods of robust controller design. In QFT design we can considers the phase information of the perturbed plant so it is less conservative than $H_{\infty}$ and ${\mu}$-synthesis methods and as be shown, it is more transparent than the sensitivity reduction methods mentioned . In this paper we want to overcome the major drawback of QFT method which is lack of an automatic method for loop-shaping step of the method so we focus on the following problem: Given a nominal plant and QFT bounds, synthesize a controller that achieves closed-loop stability and satisfies the QFT boundaries. The usual approach to this problem involves loop-shaping in the frequency domain by manipulating the poles and zeros of the nominal loop transfer function. This process now aided by recently developed computer aided design tools proceeds by trial and error and its success often depends heavily on the experience of the loop-shaper. Thus for the novice and First time QFT user, there is a genuine need for an automatic loop-shaping tool to generate a first-cut solution. Clearly such an automatic process must involve some sort of optimization, and while recent results on convex optimization have found fruitful applications in other areas of control theory we have tried to use LMI theory for automating the loop-shaping step of QFT design.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2008.06a
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• pp.617-618
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• 2008

• Journal of the Ergonomics Society of Korea
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• v.32 no.1
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• pp.97-106
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• 2013

Objective: The aim of this study is to investigate the attributing factors influencing team performance. Background: Technically, it is necessary that operators adapt themselves to computerized and advanced techniques to operate the main control rooms safely in nuclear power plant in Korea. The more main control rooms are digitalized, the more important for operators to have high team performance it is. Method: This paper analyzes team process through literatures review and elicits team performance shaping factor. Especially, the objective of this research is to elicit communication using common team performance shaping factors. Results: This study has found communication through team performance shaping factors in Main Control Room of the SMART. Conclusion: This paper can offer a starting point for team communication, which can use team performance shaping factor framework that are emerging in these new nuclear power plant. Application: As a result, I expect that the evaluation communication for MCR operator's team performance will lead the operating techniques in nuclear power industry internationally.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.253-254
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• 2006

In this investigation, the authors propose a novel method of Enveloping Helical gear generation by shaping operation and a math model to simulate its manufacturing process. The tooth geometry of the Enveloping Helical Gear is analytically determined by simulating the conjugate motion between the workpiece(Enveloping Helical gear) and cutting tool(shaper cutter) in the generation process. It is expected that such math modeling capability will give engineers an opportunity to correct manufacturing related issues in the design phase and thereby reduce the developing period.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.30A no.12
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• pp.98-107
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• 1993

This paper describes a design of a multi-bit oversampling noise-shaping D/A converter which achieves a resolution of 12 bits using oversampling technique. In the architecture the essential block which determines the whole accuracy is the analog internal D/A converter, and the designed charge-integration internal D/A converter adopts a differential structure in order to minimize the reduction of the resolution due to process variation. As the proposed circuit is driven by signal clocks which contains the information of the data variation from the noise-shaping coder, it minimizes the disadvantage of a charge-integration circuit in the time axis. In order to verify the circuit, it was integrated with the active area of 950$\times$650${\mu}m^{2}$ in a double metal 1.5-$\mu$m CMOS process, and testified that it can achieve a S/N ratio of 75 dB and a S/(N+D) ratio of 60 dB for the signal bandwidth of 9.6 kHz by the measurement with a spectrum analyzer.

• Journal of Fashion Business
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• v.17 no.2
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• pp.179-196
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• 2013

This research is about the mechanical properties of knit pullover of Shaping and WholeGarment according to structured patterns and form of the armhole. For the study 12 samples are prepared under different conditions and through comparative analysis of each sample's armhole around armpit in basic properties, tensile strength & elongation and residual elongation after repeated extensions, the conclusion is as follows. As a result of comparing basic properties of structured pattern of Shaping and WholeGarment samples, in all structured patterns Shaping samples weighed more. According to the comparative analysis of tensile strength & elongation of Shaping and WholeGarment samples, Machi on both sides of WholeGarment samples showed the highest strength. By comparing outcome of residual elongation by structured pattern of Shaping and WholeGarment samples, both types were observed to have the residual elongation increase in the order of Plain

• Journal of the Korean Society for Precision Engineering
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• v.33 no.11
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• pp.911-918
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• 2016

A conical roll-shaping process was proposed for fabrication of a metallic spiral blade applied to a small-scale wind turbine system. A spiral blade has continuously different curvatures, with a range of 100 to 350 mm radius. To fabricate this complex shape, we developed a conical roll-shaping process having two main conical rollers for feeding a blank sheet, and two cylindrical side rollers for control of local bending. For clear understanding of the process parameters, numerical analyses were conducted using a commercial code, Pam-Stamp. This study optimized the effects of process parameters, such as gap and angle between the main rollers and side rollers, and also the movement of side rollers. In order to increase the forming efficiency, a central rotation point was also calculated by the analytical approach. This developed rolling process can thus be utilized in a sheet metal forming process for obtaining spirally curved sheet metal shapes.

• Transactions of Materials Processing
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• v.12 no.6
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• pp.521-528
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• 2003

Powder injection molding (PIM) uses the shaping advantage of injection molding but is applicable to metals and ceramics. This process combines a small quantity of polymer with an inorganic powder to form a feedstock that can be molded. After shaping, the polymeric binder is extracted and the powder is sintered, often to near-theoretical densities. According1y, PIM delivers structural materials in a shaping technology previously restricted to polymers. The process overcomes the shape limitations of traditional powder compaction, the costs of machining, the productivity limits of isostatic pressing and slip casting, and the defect and tolerance limitations of conventional casting. Since 1980s when major attention was given to PIM process, it has been widening the application area from small parts with complex shape and tailored properties to structural parts requiring strength and ductility as in automotive, military and medical industries.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.8
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• pp.1482-1488
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• 2010

Recently to increase the productivity and improve the quality in the industrial process, suppressing the residual vibration in motion control systems becomes the essential problem to solve. One of the methods to suppress the residual vibration is the input shaping technique. It is based on parameters of the system model; however, the parameters are usually difficult to obtain. This paper shows the effects of the residual vibration caused by the variation of the general velocity profile for the system with two vibration modes, and also shows the effects of the input shaping filter based on the parameters of system model. Finally, the simulation results show that the proposed input shaping filter using an artificial immune algorithm is more effective for suppressing residual vibrations than genetic algorithm.

• Proceedings of the Korea Society of Design Studies Conference
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• 2004.10a
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• pp.184-185
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• 2004