• Journal of the Institute of Electronics Engineers of Korea SD
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• v.43 no.8 s.350
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• pp.35-43
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• 2006

In the paper, we propose a new method for power optimization that uses path balancing based on stochastic estimation of glitch in Statistical Static Timing Analysis (SSTA). The proposed method estimates the probability of glitch occurrence using tightness probability of each node in timing graph. In addition, we propose efficient gate sizing technique for glitch reduction using accurate calculation of sizing effect in delay considering probability of glitch occurrence. The efficiency of proposed method has been verified on ISCAS85 benchmark circuits with $0.16{\mu}m$ model parameters. Experimental results show up to 8.6% of accuracy improvement in glitch estimation and 9.5% of optimization improvement.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.1
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• pp.99-109
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• 2008

The purpose of this study was to survey sizing system and preferable ease and to decide the body measuring items for pattern making in a men's dress shirt for mass customization industry that is rising to the surface as a new production system. For this, it had a survey subjects were 254 males between 25 to 44 years old who wear dress shirt frequently and the relevant on line companies, and analyzed the garment sizing system and preferable ease. Collected data were analysed by frequency analysis, t-test, $X^2-test$, and ANOVA using SPSS 12.0 for window. Garment pattern making should reflect the sizes of the body parts well, and simplification of the ordering process would work as an important variable. In relation to the preferable ease, older people preferred more ease while younger people preferred fit ease. In relation to the sizes, people wearing the size of '110' preferred more ease than the size of '90'. And people weighing over 90kg preferred sufficient ease than less weighing. People height over 170cm people preferred sufficient ease for the length between shoulders than height under 170cm. In case of the companies had no consistent sizing system. Significant difference was found in the sizes, except for the size of '100', among those companies, there was significant difference in the length between shoulders and the length of the shirt among those companies and those sizes. Significant body parts for a garment pattern making was height, the circumference of the neck, the chest circumference, the length between biacromion, the arms length, and the waist circumference.

• Journal of Advanced Navigation Technology
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• v.23 no.1
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• pp.44-54
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• 2019

In many countries, there are needs of new transportations to replace ground congestions due to growing number of cars. In addition, the increase in the number of cars held by economic growth will further increase traffic congestion in the future. To overcome this problem, many researches have been performed for personal air vehicle (PAV). In this study, the wing loading and the power-to-weight ratio that are major design parameters for the sizing of roadable PAVs were calculated for different kinds of airfoil and engine types. I.e., in the sizing process, the study was conducted to determine the design point using the graphs of wing loading, power-to-weight ratio, brake horse power, and fuel efficiency for the given mission profiles considering domestic environments and the FAR PART 23 which is the GA class aircraft certification standard. As a result of sizing, using diesel engine require high maximum take-off weight, wing area, and power compared to gasoline engine due to more engine weight.

• Journal of Advanced Navigation Technology
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• v.22 no.2
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• pp.111-122
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• 2018

At present, the ground transportation system is saturated in many countries including Korea. To overcome this problem, many researches of developing a roadable personal air vehicle (PAV) are being carried out to alleviate traffic congestion and to accomplish door-to-door mobility through three-dimensional traffic system. In this study, the thrust-to-weight ratio, the wing loading, and the power-to-weight ratio that are major design parameters for the sizing of roadable PAVs were calculated under the constraints of ground roll, climb rate, maximum cruise speed, service ceiling, stall speed. Also, in the sizing process, the study was conducted to determine the design point using the graphs of thrust-to-weight ratio, wing loading, power-to-weight ratio, and brake horse power for the mission profiles considering domestic environments and the FAR PART 23 which is the GA class aircraft certification standard.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.11a
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• pp.209-210
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• 2007

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09b
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• pp.1278-1279
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• 2006

New product line with additional secondary operation of oil pump rotor was built in necessity of increasing capacity. This new line includes steam treatment process after sizing. The new line achieved 1.6 times higher performance compared with a conventional line.

• Journal of Electrical Engineering and information Science
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• v.3 no.2
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• pp.230-238
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• 1998

When size and shape of moving object have been changed, a correlator often accumulates walk-off error. A success of correlation-based tracking largely depends on choosing suitable window size and position and thus transferring the proper reference image to the next frame. For this, we propose the Adaptive Window Algorithm with Four-Direction Sizing Factors (AWA-FSF) for fast adjusting a reference region to enhance reliability of correlation-based image tracking in complex cluttered environments. Since the AWA-FSF is capable of adjusting a reference image size more rapidly and properly, we can minimize the influence of complex background and clutter. In addition, we can finely tune the center point of the reference image repeatedly after main tracking process. Thus we have increased stability and reliability of correlation-based image tracking. We tested performance of the AWA-FSF using 45 real image sequences made of over 3400 images and had the satisfied results for most of them.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.3
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• pp.29-39
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• 2009

In an environment of global competition, the success of a manufacturing corporation is directly related to how it plans and executes production in particular as well as to the optimization level of its process in general. This paper proposes a production planning algorithm for the Multi-Level, multi-item Capacitated Lot Sizing Problem (MLCLSP) in supply chain network considering back-order. MLCLSP corresponds to a mixed integer programming (MIP) problem and is NP-hard. Therefore, this paper proposes an effective algorithm, GRHS (GRASP-based Rolling Horizon Search) that solves this problem within reasonable computational time and evaluates its performance under a variety of problem scenarios.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.1029-1032
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• 2001

The purpose of this paper is to establish an automated die design system for compacting and sizing process required in Powder Metallurgy. Though the Powder Metallurgy(P/M) is a practical and economical forming technology, it needs long time and many trials and errors for die design. Such a problem can be solved by introduction of the automated die design system for P/M. In order to establish the system, collecting, classifying, and systematizing related knowledges from the experts in industries, books, and papers were performed. The system was constructed by AutoLISP, the language operated in AutoCAD atmosphere. This language can efficiently support for user to work on drawings. There are three modules ; P/M part specification input module, P/M part design module, and Die design module. A part for vehicle was applied to the system and satisfied results were achieved.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.40 no.3
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• pp.30-35
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• 2008

Mechanical properties of paper mulberry bast fiber handsheets were investigated to study the characteristics of bast fiber in terms of being suitable for modern paper making process. Tensile, tear and burst strength of handsheets made from bast fiber of paper mulberry were better than those of NBKP handsheets. Smoothness of bast fiber was higher but stiffness was lower than NBKP. Sizing performance of bast fiber were worse. 3D image analysis showed that handsheets of bast fiber had inferior formation and more pores comparing to NBKP.