• Korean Journal of Computational Design and Engineering
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• v.1 no.1
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• pp.56-64
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• 1996

A quadrilateral-triangular mixed grid method for the solution of incompressible viscous flow is presented. The solution domain near the body surface is meshed using elliptic grid geneator to acculately simulate the viscous flow. On the other hand, we used unstructured triangular grid system generated by advancing front technique of a simple automatic grid generation algorithm in the rest of the computational domain. The present method thus is capable of not only handling complex geometries but providing accurate solutions near body surface. The numerical technique adopted here is PISO type finite element method which was developed by the present author. Investigations have been made of two-dimensional unsteady flow of Re=550 past a circular cylinder. In the case of use of the unstructured grid only, there exists a considerable amount of difference with the existing results in drag coefficient and vorticity at the cylinder surface; this may be because of the lack of the grid clustering to the surface that is a inevitable requirement to resolve the viscous flow. However, numerical results on the mixed grid show good agreements with the earlier computations and experimental data.

• Journal of Korean Society for Atmospheric Environment
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• v.13 no.6
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• pp.463-474
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• 1997

Metallic elements in dustfall have been known as notable air pollutants directly or indirectly influencing human health and wealth. The first aim of this study was to obtain precise spatial distribution patterns of 5 elements (Pb, Zn, K, Cr, and Al) in dustfall around Suwon area. To predict isometric lines of metal fluxes deposited on unsupervised random sites, the study has applied both spatial statistics as a receptor model and a GIS (geographic information system). Total of 31 sampling sites were selected in the study area (roughly 3 by 3 km grid basis) and dustfall samples were then collected monthly basis by the British deposit gauges from Dec., 1995 to Nov., 1996. The metallic elements in the dustfall were then analyzed by an atomic absorption spectrometer (AAS). On the other hand, a base map overlapped by 7 layers was constructed by using the AutoCAD R13 and ARC/INFO 3.4D. Four different spatial interpolation and expolation techniques such as IDW (inverse distance weighted averaging), TIN (triangulated irregular network), polynomial regression, and kriging technique were examined to compare spatial distribution patterns. Each pattern obtained by each technique was substantally different as varing pollutant types, land of use types, and topological conditions, etc. Thus, our study focused intensively on uncertainty analysis based on a concept of the jackknife and the sum of error distance. It was found that a kriging technique was the best applicalbe in this study area.

• The Bulletin of The Korean Astronomical Society
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• v.40 no.2
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• pp.31.1-31.1
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• 2015

For probing magnetic fields in the universe, rotation measure (RM) have been often used. RM allows us to obtain the information of integrated (or averaged) magnetic fields along a line of sight (LOS). On the other hand, the new technique so-called Faraday tomography will be used in practical in the near future thanks to the wide-band polarimetry by Square kilometre Array and/or its precursors. The technique allows us to obtain so-called Faraday dispersion function (FDF). FDF is the distribution function of magnetic fields and polarized sources along a LOS. Because of this fact, it is expected that the studies of magnetic fields associated with various astronomical objects will progress dramatically. Since FDF also includes information of cosmic-rays and thermal electrons, the investigation of FDF may advance the studies of dynamics of external galaxies and/or the star formation activities. We have studied the potentials of Faraday tomography such as a tool to probe the intergalactic magnetic field associated with filaments of galaxies in the large scale structure. We have also studied the realistic FDFs of galaxies for understanding global magnetic field, cosmic-ray and thermal electrons of external galaxies. In the talk, we briefly introduce the Faraday tomography technique and report the results related to the Faraday tomography.

• Journal of the Korean Society of Fashion and Beauty
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• v.1 no.1 s.1
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• pp.79-94
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• 2003

The purpose of this study was to discuss how make-up materials were used for the design techniques of special make-up that is part of impersonation, what kinds of materials were applied to special make-up design and how they were utilized, in a bid to find out more materials available for each of diverse design techniques in pursuit of better make-up design. The most widely used materials were divided into transformational and supplementary types, and the focus of this study was placed on two different design techniques. One put transformational materials to use, and the other utilized supplementary materials that also could serve as alternative and effect materials. Unlike general make-up that pursues beauty, special make-up focuses on realistic effect, and it cannot make any progress without newer, diverse materials which are increasingly gaining in importance. Although special make-up designing is a skilled technique that requires systematic knowledge of theories, proper materials and repeated practice, there is no absolute standard for it, since it is a product of imagination and depends on delicate hand skills and its effect hinges on individual viewer's visual perspective. In the future, more comprehensive and broader-scale experiments are called for to tackle this problem.

• Journal of the Korean Society for Precision Engineering
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• v.4 no.2
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• pp.36-46
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• 1987

An optical technique using laser for non-contact measurement of surface roughness and form accuracy of ground surfaces is presented. It is found that, when a ground surface is illuminated by a beam of laser light, the roughness height and slope distribution has significant influence on the pattern of reflection and it maintains an unique Gaussian distribution relationship with the surface roughness. The principle idea of the optical measurement system is therefore monitor the radiation, and then calibrate it in process against surface roughness by means of necessary digital data processing. On the other hand, measuring the form accuracy of a ground surface is accomplished by using a triangular method, which is based on observing the movement of an image of a spot of light projected onto the surface. The image is focused, through a series of lenses for magnification, on a photodetector array lf line configur- ation. Then the relative movement of image and consequently the form accuracy of the surface can be obtained through appropriate calibration procedures. Experimental test showed that the optical roughness measurement technique suggested in this work is very efficient for most industrial applications being capable of monitoring the roughness heights ranging 0.1 to 0.6 .$\mu$m CLA values. And form accuracy can be measured in process with a resolution of 10 .$\mu$m.

• Journal of the Korea Furniture Society
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• v.26 no.3
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• pp.207-221
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• 2015

Inlay is a high technique of inlaying patterns on the surface of crafts and widely used transcending time and place at various hand crafting area. Inscribed pattern technique using rare materials in the area have been used by the artisans of artistic flair and functionality and its value is also highly regarded from ancient to modern and inherits and is being developed today. Existing inlay technique, however, has not been spread out because it needs craftsman's skill based on the handcraft and inscribed materials are very rare to use. This paper aims to replace natural wood Sanggam materials for traditional furniture patterns such as Samho Jang, Ohho Jang, Seongtoenoe Moon, Gyeopgwinoe Moon and wood inlay text like Soo (Long life), Bok (Luck), Kang (Peace), Ryoung (Relaxed) and gammadion cross pattern. Gathered black, yellow and white color dyed wood using power tools can replace rare natural inlay materials through reliable and standardized supply. Dyed-gathered inlay materials can easily replace wood inlay materials, therefore, attempt to create an improved direction regarding materials and fabrication techniques in order to make traditional or contemporary artistic furniture to be produced.

• Journal of Korean Academy of Nursing
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• v.28 no.3
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• pp.650-661
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• 1998

The purpose of this study was to provide fundamental data for determining contents of Fundamental Nursing Practice and developing desirable bedside nursing techniques for clinical nursing areas. Subjects for this study were 86 nurses who were employees of two university hospitals located in Seoul and a district area. Data were collected by questionnaires. Items of Fundamental Nursing Practice were classified into 72 items according to the result from content analysis of 9 textbooks of Fundamental Nursing. The results are as follows : 1) Items which above 80% of respondents practiced during the school inside practice or clinical nursing practice course were axillary temperature measurement, radial pulse measurement, respiratory rate measurement, application of oral hygiene, hand-washing technique, application of hot and cold bags, intramuscular injection technique, open bed-making, soap enema method, application of nelaton catheterization and oral and nasal suction methods. 2) Above 90% of respondents replied that all items except temperature measurement and bed-making were requisite contents for Fundamental Nursing Practice. Above 10% of respondents replied oral and rectal temperature measurement and bed-making were unnecessary content. 3) Above 90% of respondents replied that operating methods of all items except isolation technique, admission and discharge procedures, and retention enema in the Fundamental Nursing Practice course and clinical situation were consistent. The main reasons that respondents did not apply methods which they learned in the Fundamental Nursing Practice course to the clinical situation were 'insufficient time', 'colleagues were using different methods', 'insufficient supply of instuments' or 'inappropriate appliances'.

• Proceedings of the SAREK Conference
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• 2009.06a
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• pp.603-607
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• 2009

About a Structure is performance external insulation is fundamantal performance for enrgy-saving. these day, most of residential structures have constructed by internal insulation method structure. The method structure internal insulation have construction and economical efficiency, but on the other hand, be generated heat loss by heat bridge especially, be generated loss heat-energy logical consequence in structure ondol. The external insulation structure method has a mert able to minimum to loss heat about heat-bridge. But the external insulation technique is unsatisfactory statues within the know-how and method of construction and materials compared with developed countries. The recently, the requirement of market related to the external insulation technique is resulted by the energy efficiency system, but it can lead to the lack of alternative technique In study on the korea type passive house building design for insulation block method of wall system has to experimental characteristic heat-energy of practice building. In result field-experimental, the heat-bridge appeared to characteristic spent heat-energy of blow 2L class and have a suffience performance it.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.10
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• pp.938-945
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• 2003

We fabricated Ni-substrate for YBCO coated conductors and evaluated the effects of pressing and annealing temperature and time on texture. Ni substrate was fabricated by powder metallurgy technique and compacts were prepared by applying uniaxial or isostatic pressure. The texture of substrate made by applying cold isostatic pressure (CIP) was stronger than that by uniaxial pressure which we attribute to the fact that the CIP method provided higher density and more uniform density distribution. It was observed that the substrate annealed at 400 C showed both retained texture and recrystallized texture. On the other hand, the texture of substrate significantly improved at annealing temperature above 500 C, forming strong 4-fold symmetry, [111] II ND texture, and FWHM of 9∼10 . It is to be noted that the degree of texture was almost independent of annealing temperature (500∼1000 C) and annealing time(1∼54 min, at 1000 C). EBSD and AFM analysis indicated that 99% of grain boundaries was low angle grain boundary and RMS was approximately 3 nm, respectively. Development of strong cube texture and high fraction of low angle grain boundary of Ni-substrate made by powder metallurgy technique in our study is considered to be suitable for the application of YBCO coated conductors.

• Journal of the Korean Society for Nondestructive Testing
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• v.24 no.6
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• pp.590-596
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• 2004

Neural network-based signal classification systems are increasingly used in the analysis of large volumes of data obtained in NDE applications. Ultrasonic inspection methods on the other hand are commonly used in the nondestructive evaluation of welds to detect flaws. An important characteristic of ultrasonic inspection is the ability to identify the type of discontinuity that gives rise to a peculiar signal. Standard techniques rely on differences in individual A-scans to classify the signals. This paper proposes an ultrasonic signal classification technique based on the information tying in the neighboring signals. The approach is based on a 2-dimensional Fourier transform and the principal component analysis to generate a reduced dimensional feature vector for classification. Results of applying the technique to data obtained from the inspection of actual steel welds are presented.