• Journal of Advanced Marine Engineering and Technology
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• v.23 no.4
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• pp.523-532
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• 1999

This study is aimed to obtain fundamental knowledge of pulse laser welding phenomena the authors investigated the structure and composition of evaporated particles of Al alloys in air and in the Ar atmosphere during pulsed laser welding. The ultra-fine particles of 5 to 100nm diameter in a globular or irregular shape were formed in laser-induced plasma and the main structure was $MgAl_2O_4$ The composition of particles was ifferent depending on the power density of a laser beam; namely under the low power density conditions magnesium was predominant in the parti-cles while aluminium content increased with an increase in the power density. These results were attributed to evaporation phenomena of metals with different boiling points and latent heats of vaporization. On the other hand the number density of laser-induced plasma species was obtained by Saha's equation. it was confirmed that the number density depends upon the plasma tempera-ture and total pressures.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.25 no.1
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• pp.20-26
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• 2015

Objectives: To evaluate the biodurability of Korean Chrysotile(KC), the changes in fibers numbers and changes in the element composition of fibers from the lung of Sprague-Dawley rats instilled KC(average size $4.74{\mu}m$, $59,043{\times}10^6$ fibers/mg) was estimated. Methods: Rats were administered 1 mg KC(low group) or 2 mg KC(high group) by a single intratracheal instillation. At each time point(5 days, 5 weeks, 10 weeks), the numbers of KC fibers and the changes of element composition(atomic %) of KC fibers from the lung of the rats were analyzed with transmission electron microscope equipped with energy dispersive X-ray spectrometer. Results: Over time, the number of fibers within the lungs of animals were reduced. The average length of the low and high group is significantly reduced from 5 days after administration. Over time, the fiber ratio of at least $5{\mu}m$ remaining in the lung tissue of the low concentration group was up but the high group was reduced. From day 5 after administration, the composition ratio(Mg) was significantly decreased in all groups. Conclusions: Size and composition of Korean Chrysotile in the lung tissue of rats was changed from 5 days.

• Journal of the Korean Wood Science and Technology
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• v.24 no.1
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• pp.1-10
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• 1996

The frequency distribution diagrams of Korean diffuse-porous woods, 36 families, 75 genera, 145 species, 215 specimens in relation to habit and phenology were analyzed. As the habit character changes from shrub to tree, such quantitative features as vessel frequency, percentage of solitary vessels, length/diameter(L/D) ratio of vessel element decreased but tangential vessel diameter, fiber length/vessel element length(F/V) ratio increased. Qualitative features such as helical vessel wall thickening, diffuse distribution of longitudinal parenchyma, heterogeneous ray composition decreased, while alternate intervessel pits, libriform wood fiber, simple perforations increase. As the phenology character changes from evergreen to deciduous species, such quantitative features as percentage of solitary vessels, vessel element length and L/D ratio decreased but tangential vessel diameter, F/V ratio increased. Diffuse distribution of longitudinal parenchyma, heterogeneous ray composition, and crystals in qualitative features decreased, while alternate intervessel pits, libriform wood fiber, simple perforation of vessel element, ray width and ray height increased.

• Journal of architectural history
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• v.18 no.2
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• pp.7-26
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• 2009

The purpose of this paper is the study on the architectural characteristics revived from the roman architecture, focused on the early renaissance architecture building. The results of study are as follow: 1. The composition system of Domus which is formed of urban house in the Roman period is presented by spatial arrangement of palace architecture centering around atrium in the Renaissance period. Thus plan type of Domus is used by atrium from which is composed of peristyle from the palace and villa in the Renaissance period. 2. The circular temple in the Roman period is composed of element such as podium, stair, peristyle centering around the basic circular plan. Bramante planed to revive above elements for the Tempietto to concept from the circular temple in the Roman period. 3. The triumphal arch in the Roman period is strong monument to the independent building in the city, but thus arch is used of church facade as the important example which is composed with building elevation in the Renaissance period. 4. The composition system and element of Roman temple which is planned to rectangular plan is composed of high podium, stair, portico, prostyle and pediment. The facade plan of church is used by the partial elements and total elements perfectly from the temple in the Roman period. 5. The linearly successive and repetitive composition which is composition system and element of aqueduct arches of same dimension shows to the palace facade, arcade for gallery space and side elevation plan of S.Fracesco church. 6. Such as background of Colloseum, Rucellai palace can be called good example which is created by the new architectural form to the creative starting point from the classical architecture from.

• Korean Institute of Interior Design Journal
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• v.17 no.5
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• pp.23-30
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• 2008

This thesis aims to analyze the visual perceptual effects drawn by 'axial composition and divergence' and to interpret the architecture of Kahn in respect of 'axial composition and divergence'. Axial composition of the form, the location of the entrance and divergence of internal movement were checked up about 53 works by extracting parti which is basic element of spatial composition. The 3D modeling simulation was performed for the selected 10 works in order to analyze the visual perceptual effect due to divergence of the internal movement. The reaction of the observer's actions and visual perception by 'axial composition and divergence' is presented in the following steps. 1. Divergence of the entrance/a panorama of expanding planes. 2. Divergence of internal movement/The process of perception of visual rotation and central spatial form. 'Perceptive form' created by 'divergence' is the result of diverse and flexible series of processes which must be experienced in person in order to reach the space as a room with a definite domain and center.

• Proceedings of the KWS Conference
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• 2002.10a
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• pp.551-554
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• 2002

As a general rule, the brazing process between cemented carbides and steel used by Silver (Ag) type brazing filler. The composition of Ag type filler were used Ag-Cu-Zn-Cd type filler mainly. But, the demand of Cadmium (Cd)-free in Ag type filler was raised recently. The reason why Cd-free in Ag brazing filler were occupied to vaporize as a CdO$_2$ when brazing process, because of Cd element was almost low boiling point of all Ag type filler elements. And, CdO$_2$ was a very harmful element for the human body. This experiment was developed Cd-freeing on Ag type filler that was used Indium (In) instead of Cd element. In this experiment, there were changed from 0 to 5% In addition in Ag brazing filler and investigated to most effective percentage of Indium. As a result, the change of In addition instead of Cd, there was a very useful element and obtained same property only 3% In added specimens compared to Cd 19% added specimens. These specimens were obtained same or more deflective strength. In this case, there were obtained 70 MPa over strength and wide brazing temperature range 650-800 C. A factor of deflective strength were influenced by composition and the shape of $\beta$ phase and between $\beta$ phase and cemented carbides interface. Indium element presented as $\alpha$ phase and non-effective factor directly, but it's occupied to solid solution hardening as a phase. $\beta$ phase were composed 84-94% Cu-Ni-Zn elements mainly. Especially, the presence of Ni element in interface was a very important factor. Influence of condensed Ni element in interface layer was increased the ductility and strength of brazing layer. Therefore, these 3% In added Ag type filler were caused to obtain a high brazing strength.

• Journal of Korea Foundry Society
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• v.31 no.4
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• pp.212-217
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• 2011

The effects of alloying element and grain refinement on the tensile properties of magnesium alloy poured into sand mold were investigated. The strength of magnesium alloy was greatly increased by the addition of aluminium and that was increased with the increased aluminum content added up to 8.10 wt% and decreased beyond that. Even though the strength of Mg-8.10 wt%Al alloy was rather decreased by the addition of zinc, that was increased with increased zinc content added up to 0.50 wt% and decreased with the increased one beyond that. The maximum tensile strength was obtained with 0.50 wt%Mn added. The strength and elongation were simultaneously increased with grain refinement and the optimum amount of strontium addition for this was 0.30 wt%. The optimum chemical composition was obtained and the yield strength, tensile strength and elongation of the alloy with this composition were 90.2, 176.3MPa and 4.43%, respectively.

• Journal of Korea Society of Digital Industry and Information Management
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• v.9 no.3
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• pp.13-20
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• 2013

In this paper, we propose a multi-scale crack detection method. This method uses decomposition, composition, and shape properties. It is based on morphology algorithm, crack features. We use a morphology operator which extracts patterns of crack. It segments cracks and background using opening and closing operations. Morphology based segmentation is better than existing integration methods using subtraction in detecting a crack it has small width. However, morphology methods using only one structure element could detect only fixed width crack. Thus, we use decomposition and composition methods. We use a decimation method for decomposition. After decomposition and morphology operation, we get edge images given by binary values. Our method calculates values of properties such as the number of pixels and the maximum length of the segmented region. We decide whether the segmented region belongs to cracks according to those data. Experimental results show that our proposed multi-scale crack detection method has better results than those of existing detection methods.

• Journal of the Korean housing association
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• v.10 no.4
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• pp.11-21
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• 1999

The purpose of this study is to analyze the interrelation of architectural composition and type of windows and doors in Korean traditional architecture. Windows and doors type, in Korean traditional architecture, is one of the important element which used to playa great role in building's physical fasade, so that used to subjected the building as a whole. In this study, the investigations on the totally 88 Korean Buddhist Temples are made, and the analysis are made according to the physical size of buildings (length and height of JUGAN), composition of JUGAN, and existence of RUGAK. The result of this study indicates that there are outstanding typical differences of traditional windows and doors in advance to variation in the physical size of building, though there are numerous interrelation between typical differences of traditional windows and doors and composition of building as a whole.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.857-860
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• 1997

The purpose of this research was to study the influence of machining characteristics for aluminum alloys. The effect of metallic microstructural variables on the measures of machinability of aluminum alloys has no been adequately investigated. Machining Characteristics are influenced significantly by mechanical characteristics, composition and structure of material etcs. For improvement of machining characteristics, various studies are reported. In this paper, composition elements add to aluminum alloys within the limit of sustaining mechanical characteristics of metallic material. We have analyzed dynamic characteristics of cutting resistance, tensile strength value, hardness value etcs.