• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1201-1206
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• 2004

This paper deals with the numerical analysis of natural convection flow induced by the density inversion effect of water inside horizontal pipe. The numerical method is based on SIMPLE/PWIM in general coordinate for its wide applicabilities. The numerical tool was validated through the comparison with the previous results concerning the density inversion effect of water It is shown that the developed numerical tool could predict the flow pattern and the heat transfer phenomena qualitatively And it is also found that the density inversion effect of water has significant effects on the flow pattern.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2005.05a
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• pp.349-353
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• 2005

This paper describes the variations of resonance frequencies and vibration mode shapes of laser welded cold rolled carbon steel plate(SCP1) induced by thermal loading during laser welding processing. The characteristics of those are analyzed with stroboscopic ESPI. Electronic speckle pattern interferometry (ESPI) that the electronic processes were added to SPI is one of the very powerful method in the experimental vibration analysis field. Stroboscopic ESPI to make it reliable are compared with theory and experimental method: Finite Element Method(FEM) and Scanning Laser Doppler Vibrometer(SLDV). The results of stroboscopic ESPI are well agreed with SLDV and also the comparison with theory give good agrement within $5\%$.

• Journal of Plant Biology
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• v.36 no.1
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• pp.43-49
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• 1993

In order to survey possibility to produce saikosaponin from in vitro hairy root culture, culture of callus, adventitous root, and hairy root of Bupleurum falcatum L. were estabilished, and quantitative and qualitative aspects in saikosaponin extracted from these were compared with those of cultivated root. Callus grew well in MS medium containing 0.9 $\mu$M 2, 4-D. In contrast, both of adventitous root and hairy root grew well in hormone-free MS medium. However, hairy root showed more rapid growth with extensive lateral root branches, characteristics of lower content of water and softer than in adventitous root. Among the selected lines of adventitous root and hairy root were observed difference in the growth rate. Mannopine, one of opine synthesized in the transformed tissue with Agrobacterium rhizogenes. A4 were detected in the extract of hairy root lines. Pattern and content of crude saponin from adventitous and hairy root showed no difference, but somewhat difference from those of cultivated root. However, in callus, distinct production-aspect of saponin was not observed.

• Applied Science and Convergence Technology
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• v.23 no.1
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• pp.54-59
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• 2014

The roll-to-roll (R2R) fabrication method to make micro-scale pillar arrays for biomimetic functionalization of surfaces is presented. Inspired by the micro-structure of plants in nature, a surface with a synthetic micro-scale pillar array is fabricated via maskless photolithography. After the surface is SAM (self-assembled monolayer) coated with trichlorosilane in a vacuum desiccator, it displays a hydrophobic property even in R2R replicas of original substrate, whose properties are further characterized using various pitches and diameters. In order to perform a comparison between the original micro-pattern and its replicas, surface morphology was analyzed using scanning electron microscopy and wetting characteristics were measured via a contact angle measurement tool with a $10{\mu}L$ water droplet. Efficient roll-to-roll imprinting for a biomimetic functionalized surface has the potential for use in many fields ranging from water repelling and self-cleaning to microfluidic chips.

• Journal of the Korean Home Economics Association
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• v.34 no.5
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• pp.249-264
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• 1996

The purpose of this study was to investigate automatic manipulating functions of dart of CAD system, and to classify the dart of women's front bodice. The results from this study: 1.3 CAD systems, were compared in automatic manipulating functions of dart. Gerber system & Investronica system were based on the pivot-method of dart manipulating, Yuka system was based on the slash-method. 2. It is classified and made a dart-design chart with using darts, which were as examples related to dart manipulating in text & reference of the pattern design. 3. In case of education of dart manipulation, the classified dart-design chart provides variations of a basic pattern through dart manipulation.

• Journal of the Korean Data and Information Science Society
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• v.16 no.1
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• pp.95-106
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• 2005

Complete-case analysis is easy to carry out and it may be fine with small amount of missing data. However, this method is not recommended in general because the estimates are usually biased and not efficient. There are numerous alternatives to complete-case analysis. A natural alternative procedure is available-case analysis. Available-case analysis uses all cases that contain the variables required for a specific task. The EM algorithm is a general approach for computing maximum likelihood estimates of parameters from incomplete data. These methods and multiple imputation(MI) are reviewed and the performances are compared by simulation studies in monotone missing pattern.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.48 no.1
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• pp.76-81
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• 1999

The degree of relative similarity between 2D patterns is obtained using Open-Ball Scheme. Open-Ball Scheme employs a method of transforming the geometrical information on 3D objects or 2D patterns into the features to measure the relative similarity for object(patten) recognition, with invariance on scale, rotation, and translation. The feature of an object is used to obtain the relative similarity and mapped into [0, 1] the interval of real line. For decades, Moment-Invariant Method has been used as one of the excellent methods for pattern classification and object recognition. Open-Ball Scheme uses the geometrical structure of patterns while Moment Invariant Method uses the statistical characteristics. Open-Ball Scheme is compared to Moment Invariant Method with respect to the way that it interprets two-dimensional patten classification, especially the paradigms are compared by the degree of closeness to human's intuitive understanding. Finally the effectiveness of the proposed Open-Ball Scheme is illustrated through simulations.

• Journal of the Korea Institute of Military Science and Technology
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• v.13 no.4
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• pp.511-519
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• 2010

This paper presents the modeling and validation of a pile-driver breech fatigue testing system model to replicate actual high pressure in a large caliber gun barrel. A hysteresis damping function was incorporated in the nonlinear impact force model. Test of real pile-driver breech fatigue testing system had been performed for model validation. Comparison of the experimental result and model simulation during impact were made. Numerical studies were performed to evaluate how the actual chamber pressure pattern in the live firing of gun barrel was affected by parameters' variation. Some of the parameters simulated included input velocity, damping coefficient and stiffness. As a result, a variety of actual chamber pressure pattern could be reproduced and controlled through current simulation model.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.04a
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• pp.43-44
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• 2006

We have studied effect of Patterned Vertical Alignment (PVA) mode on electro-optical characteristics and stability of liquid crystal director upon electrode pattering. In the present studies, LC director field and stability of conventional PVA mode electrode patterns were analyzed and new type of electrode patterns were suggested. At last, comparison between this new type of electrode patterns to conventional electrode pattern types were followed.

• Journal of Preventive Medicine and Public Health
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• v.16 no.1
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• pp.121-127
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• 1983

To identify the changes in professional services pattern after introducing the deligated system of claims review started in 1982, a university hospital under this system was examined. For comparison, claims of the hospital to Federation of Korean Medical Insurance Societies, where this system is not accepted, were reviewed. A total of 600 cases each were studied operated at the Departments of General Surgery & Orthopedic Surgery in 1981 and 1983. The results are summarized as follow: 1. Percentages of hospital charges for basic care was decreased by 10.2% and that for medical service increased by 8.4% in 1983. 2. After the introduction of the deligated review system, percentages of cutting off the claims was decreased by 12.4% for basic care and increased by 3.8% for medical services. 3. Percentage of testing liver function, and the frequency of administering high cost intravenous fluid injection, applicating Robinul as anesthetic premedication were decreased respectively after introducting the deligated services system.