• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.31 no.2
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• pp.1-9
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• 2003

In the present study, a 3-D Parallel DSMC method in developed on unstructured meshes for the efficient simulation of rarefied gas flows. Particle tracing between cells in achieved based on a linear shape function extended to three dimensions. For high parallel efficiency, successive domain decomposition is applied to achieve load balancing between processors by accounting for the number of particles. A particle weighting technique is also adopted to handle flows containing gases of significantly dirrerent number densities in the same flow domain. Application is made for flow past a 3-D delta wing and the result is compared with that from experiment and other calculation. Flow around a rocket payload at 100km altitude is also solved and the effect of plume back flow from the nozzle in studied.

• Women's Health Nursing
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• v.2 no.2
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• pp.270-283
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• 1996

This study was done for the purpose of analyzing the relationship between menopausal symptoms and depression. Data were collected by a questionnaire from November 28 to December 30, 1995. The subjects were 134 women between 40-61 years of age. The instruments used for this study were The Menopausal symptom scale by Neugartom and Depression scale by Zung. The results of the study were as follows. 1. Mean score of menopausal symptoms was 1.59. Mean score orders of experienced symptoms were "Rack pain and joint pain"(2.02), "General weakness"(1.98), "Nervousness"(1.96). The most serious menopausal symptom was psychosomatic symptom.(1.88) Total score orders of experienced symptoms was 27.9 and over 90.3% of women complained menopausal symptom. 2. Mean score orders of depression was 39.13. It was normal range of depression. 85.1% of the women were normal range of depression and 14.2% of women mild depression. 3. The relationship between menopausal symptoms and depression was statistically significant(r=0.5307, p=0.000). When the relationship among three dimensions of menopausal symptoms were explored the psychosomatic symptom(r=0.4090, P=0.000), Physical symptom(r=0.319, P=0.000), Physical symptom(r=0.319, P=0.000) were statistically significant. 4. General characteristic variables were significantly related to the level of menopausal symptoms as follows ; environment of living(F=2.89, p=0.038), religion(F=4.18, P=0.007), times of birth(F=2.66, p=0.043). The analysis of this study have implication for management of middle aged women's health, to solve the nursing problems, and to prevent and relieve climacteric symptoms.

• Journal of Powder Materials
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• v.20 no.5
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• pp.376-381
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• 2013

Spherical Ti-6Al-4V powders in the size range of 250 and 300 ${\mu}m$ were uniformly doped with nano-sized hydroxyapatite (HAp) powders by Spex milling process. A single pulse of 0.75-2.0 kJ/0.7 g of the Ti-6Al-4V powders doped with HAp from 300 mF capacitor was applied to produce fully porous and porous-surfaced Ti-6Al-4V implant compact by electro-discharge-sintering (EDS). The solid core was automatically formed in the center of the compact after discharge and porous layer consisted of particles connected in three dimensions by necks. The solid core increased with an increase in input energy. The compressive yield strength was in a range of 41 to 215 MPa and significantly depended on input energy. X-ray photoelectron spectroscopy and energy dispersive x-ray spectrometer were used to investigate the surface characteristics of the Ti-6Al-4V compact. Ti and O were the main constituents, with smaller amount of Ca and P. It was thus concluded that the porous-surfaced Ti-6Al-4V implant compacts doped with HAp can be efficiently produced by manipulating the milling and electro-discharge-sintering processes.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.2
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• pp.67-81
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• 1988

The purpose of the present study is to set up an efficient optimum design method for the large-scale reinforced concrete cylindrical shell structures like intake tower of reservoir and to establish a solid foundation for the automatic optimum structural design combined with finite element analysis. The major design variables are the dimensions and steel areas of each member of the structures. The construction cost which is composed of the concrete, steel, and form work costs, respectively, is taken as the objective function. The constraint equations for the design of intake-tower are derived on the basis of the working stress design method. The corresponding design guides including the standard specification for concrete structures have been also employed in deraving the constraint conditions. The present nonlinear optimization problem is solved by SUMT method. The reinforced concrete intake-tower is decomposed into three major substructures. The optimization is then conducted for both the whole structure and the substructures. The following conclusions can be drawn from the present study. 1. The basis of automatic optimum design of reinforced concrete cylindrical shell structures which is combined with finite element analysis was established. 2. The efficient optimization algorithms which can execute the automatic optimum desigh of reinforced concrete intake-tower based on the working stress design method were developed. 3. Since the objective function and design variables were converged to their optimum values within the first or second iteration, the optImization algorithms developed in this study seem to be efficient and stable. 4. The difference in construction cost between the optimum designs with the substructures and with the entire structure was found to be small and thus the optimum design with the substructures,rnay conveniently be used in practical design. 5. The major active constraints of each structural member were found to be the tensile stress insteel for salb, the minimum lonitudinal steel ratio constraints for tower body and the shearing stress in concrete, tensile stress in steel and maximum eccentricityconstraints for footing, respectively. 6. The computer program develope in the present study can be effectively used even by an unexperienced designer for the optimum design of reinforced concrete intake-tower.

• The Journal of the Korea Contents Association
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• v.10 no.10
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• pp.172-179
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• 2010

The study on works motivated from interest in the nature of matters and inherent visual-perceptual structure in them aims at expressing formative continuity of the connections of three dimensions of simple geometrical shapes such as circles and lines, which are characteristics of shape of molecules. With such a purpose, this study examined the geometrical shapes in modern arts and structural connection and symbolism of molecule structure, and based on such considerations, it expressed successive formative beauty which comes from repetitive connection between units by creating stereogram of simple geometrical shapes of molecule structure. The types of works include a method of connecting the units of molecule models and molecules seen in electron microscope with lines as a parameter and connecting units directly, which are used to express body accessory and metallic sculptures. Consequently, it attempted formation occurring spatial composition of continuity of division and duplication through direct connection between units and circular continuity coming from connection of simple geometrical shapes of molecule images such as spheres and curves transformed into stereogram.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.6
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• pp.3363-3369
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• 2014

Recently, considerable effort has been made to maintain a pleasant and safe indoor environment in buildings. For this, the use of a ventilation system attached to a range hood in kitchens has prevailed. Accordingly, diversiform designs for range hoods have been used. Press molding is normally used for range hood construction for several reasons. On the other hand, its economic efficiency is low in the case of a small production work. Considerable research has been carried out to solve this problem and it is believed that it is useful to use the change core method to develop molds. This study designed the core of a mold using the change core method and a total of four processes were used in its manufacture. As a result, the press molds, which are needed for shorter production runs and whose form is changeable, were developed. In addition, after the measurements in three-dimensions, the specimen passed a test within a tolerance of ${\pm}2.00mm$.

• Journal of Astronomy and Space Sciences
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• v.20 no.4
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• pp.239-248
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• 2003

We completed the light curves of near-contact binary system AX Dra for 11 nights from March 2001 to May using the 61-cm reflector and VR filters at Sobaeksan Optical Astronomy Observatory. From our observations, seven new times of minimum light (three timings to. primary eclipse, four. for. secondary) and the light elements consistent with recent observations were determined. Using the Wilson-Devinney binary code and the q-search method, we analyzed our VR light curves for various Roche configurations and mass ratios. As the results, we found the eclipsing binary AX Dra to be the FO Vir-type near-contact binary system interpreted as a detached or a semi-detached system, with the secondary filling its Roche lobe and the primary almost. Unlike the statistical study(Shaw 1994) of the FO Vir-type near-contact binary system, our VR light curves showed the O'Connell effect of all the same type and it's dimensions was about $0^{m}.008$.

• KIEAE Journal
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• v.10 no.3
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• pp.117-125
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• 2010

Entering into the 21th century, the whole world is facing the various problems such as environmental disruption, resource exhaustion, and social isolation due to the consequences of population growth and economic development. Especially, as the world population is aging, the solutions for these problems are being suggested with a new paradigm of environmental design for sustainable society providing more affluent and safer life for them. Aging societies are experiencing the difficulty in pursuing persistent vitality of life when aged population is socially excluded, and communities are stagnant due to the decrease of economic activities. In other words, those factors are causing the problems of social sustainability associated with the vital duration of local society and communities. In order to develop successful environment for aging society, it is necessary for us to precisely review how advanced countries are changing their directions. Therefore, the purpose of this study is to examine current trends of the aging friendly environment and find out the measures to promote social sustainability under the crisis of aging society. For this purpose, using qualitative methods, this study analyzed the contents presented at a professional conference , that showed current trends clearly, into three dimensions of social sustainability; the social integration of senior living communities with local society, the vitality of the communities, and the invigoration of individual senior lives. As a result, this study found that the measures that attempt to enhance the social sustainability of aging population can be also used to invigorate the communities.

• Computers and Concrete
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• v.10 no.2
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• pp.135-147
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• 2012

At mesoscale, concrete is considered as a three-phase composite material consisting of the aggregate particles, the cement matrix and the interfacial transition zone (ITZ). The reconstruction of the internal structures for concrete composites requires the identification of the boundary of the aggregate particles and the cement matrix using digital imaging technology followed by post-processing through MATLAB. A parameter study covers the subsection transformation, median filter, and open and close operation of the digital image sample to obtain the optimal parameter for performing the image processing technology. The subsection transformation is performed using a grey histogram of the digital image samples with a threshold value of [120, 210] followed by median filtering with a $16{\times}16$ square module based on the dimensions of the aggregate particles and their internal impurity. We then select a "disk" tectonic structure with a specific radius, which performs open and close operations on the images. The edges of the aggregate particles (similar to the original digital images) are obtained using the canny edge detection method. The finite element model at mesoscale can be established using the proposed image processing technology. The location of the crack determined through the numerical method is identical to the experimental result, and the load-displacement curve determined through the numerical method is in close agreement with the experimental results. Comparisons of the numerical and experimental results show that the proposed image processing technology is highly effective in reconstructing the internal structures of concrete composites.

• The Research Journal of the Costume Culture
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• v.15 no.2 s.67
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• pp.193-202
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• 2007

The purpose of this study was to find out effects of textile motifs and the application methods on wearer's image perception. A survey was conducted to total of 255 male and female university students who are residing in Daejeon and Chungnam province. The stimuli were composed of 2 level tones(dark and light), 3 level complexity(simple, medial and complex), 3 patterns(polka dot, stripe and check) and the 2 way of stimuli application methods(fabric and garment). The instrument for measuring preference of stimuli consisted of 4 items, encouraging, preference, purchasing and popularity. The instrument for measuring image of stimuli consisted 24 pair items. Factor analysis for the adjective pair images(24 inquiries) about the textile patterns which were used in this study was performed. It resulted as three factors which are attraction, salience, and potential. Attraction, salience, and potency dimensions showed the most significant interaction effects of application methods and patterns. And tone and application method effected attraction and salience, tones and patterns effected attraction, tones and complex effected salience. Application methods and patterns effected potential and patterns and complex effected salience. The preferences toward stimuli, it resulted only interaction of tones and patterns affected the preferences('total preference' and 'purchasing'). Pearson's product-moment correlation analysis carried out to find out the relation of images of clothing and preferences. As a result, salience was significant relation with attraction and potency. In correlation between image of textile pattern and preference, attraction is most significant relation with the preference. The results of the study could be used for the marketing strategies of the motif in fashion product.