• Journal of the Korean Society for Aviation and Aeronautics
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• v.12 no.2
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• pp.17-28
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• 2004

In unmanned aerial vehicle (UAV), the high temperature results from friction with the air, combustion of fuel and combustion gas of a nozzle etc. It causes serious problems in the UAV structure. The characteristic analysis of heat resistant metal and ceramic materials and creep analysis for the functionally graded material (FGM) is presented in this paper. FGM is composed of two constituent materials that are mixed up according to the specific volume fraction distribution in order to withstand high heat condition. In addition, the creep behavior of FGM applied in duct structure of an engine is analyzed.

• Journal of the Korean Society for Heat Treatment
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• v.16 no.2
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• pp.78-82
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• 2003

Nitrided compound layer and diffusion layer structure were observed by SEM. The compound layer and the constituent of nitrided surface of STS 304, STS 316, STS 410 and SACM 645 steel were analysed using EMPA and XRD respectively. The depth of nitriding layer that is obtained from similar nitriding condition decrease in the order of SACM 645 > STS 410 > STS 316 > STS 304. Result of phase transformation of the nitrided at $550^{\circ}C$ by XRD analysis were as follows; The austenitic stainless steel was mainly consist of $Cr_2N$ accompanying with $Fe_4N$ and $Fe_{2-3}N$ phase and martensitic stainless steel was mainly consist of present $Fe_{2-3}N+Cr_2N$ phase, but SACM 645 steel was $Fe_{2-3}N$ phase present only.

• Journal of the Korean housing association
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• v.15 no.2
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• pp.63-73
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• 2004

Louis I. Kahn's spacial composition is characterized by traditional motives and Ecole des Beaux which had influenced him. This influence had showed five forms about Kahn's spacial composition. His constituent factors in geometrical form are classified into the propositional system, the cellular multiplication of a special unit, the Poche Space and others. According to the results of this study obtained from above mentioned subjects, it can be concluded that geometrical factors, which constitute space of plan, are totally expressed as a system of order which unites particular ones into whole one. This characteristic had developed into a completed meaning for passing through the residential architecture in 1950's, and showed in the other artworks there after.

• Journal of Korean Society of Rural Planning
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• v.3 no.1
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• pp.54-67
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• 1997

Korean societies have been experiencing the wholesale structural changes in the rapid currents of recent openness, globalization and democratization, which effect much more heavily in rural areas than in urban areas, so rural recomposition works being an important national concern. In order to systematically reconstruct the rural structure, the decision makers, with a four step hierarchy of rural resident-residents group-community-region, should be endowed with the objective judgement on basic elements of resource potentialities under their control. In this process. rational resource evaluation works would be firstly necessiated from expert groups. Based on the view mentioned above, this study principally aimed at developing a rational evaluation framework for rural resources. For that objective, the first step of the study pigeonholed the total resources items identifiable in rural areas from the existing study results, spatial planning and field surveying data. After then, using the formalized classification criteria of resources items, a tentative goal system for rural resources evaluation was proposed and the final one determined through expert-group checking. The results obtained during the study are summarized as follows ; 1. Using the existing examples of resources identification/classification and the basic data list for county-level development planning as the principal reference ones, total rural resources elements were classified into 3 constituent units : land, natural environment and human resources, which correspond to places to work, to play and to live, respectively, as 3 constituent ones of life-supporting space. 2. Three characteristic areal types were adopted to represent the total rural areas : lowland, upland and seashore areas, and also 3 practical use types to represent the objectives of resources evaluation systems : for land use planning, natural conservation policy and village improvement planning. Thus 9 different types of goal system for resources evaluation were developed(each system by 3 areal typesX3 practical use types) 3. Each goal system has 3-tier classification steps from the higher, middle and lower one. The higher and middle steps should contain equally applicable components to all the rural areas, of which allowable number being around 3 and 4 respectively. However the lower step would contain detailed sub-components changeable to areal characteristics of which allowable number being around 7.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.1
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• pp.13-20
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• 2008

Graded layers in which two different constituent particles are mixed are inserted into functionally graded material such that the volume fractions of constituent particles vary continuously and functionally over the entire material domain. The material properties of this dual-phase graded region, which is essential for the numerical analysis of the thermo-mechanical behavior of FGM, have been predicted by traditional homogenization methods. But, these methods are limited to predict the global equivalent material properties of FGMs because the detailed geometry information such as the particel shape and the dispersion structure is not considered. In this context, this study intends to investigate the characteristics of these homogenization methods through the finite element analysis utilizing the discrete micromechanics models of the graded layer, for various volume fractions and external loading conditions.

• Journal of Society of Preventive Korean Medicine
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• v.20 no.1
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• pp.99-110
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• 2016

In Korea and China, traditional medicine's holistic approaches, based on the views of whole-body and whole-person, have been applied to make the solution of health problem. However, these holistic approaches of traditional korea or chinese medicine have been limited in interpreting their theories in a view of modern scientific aspects of medicine. This limitation seems to be mainly due to the reductionism approaches of modern scientific medicine. Traditionally, science has taken a reductionism approach; dissecting biological systems into their constituent parts and studying them in isolation. However, systems biology based on omics technologies is providing a new thought and method for traditional medicine's research and interpretation. Systems biology uses integrity study as the characteristic and bioinformatic technology as the key method for connecting reductionism and holism. Therefore, it has much in common with the theory of traditional medicine. It was reviewed that how systems biology is applied to traditional medicine in Korea and China. Also it was suggested that more future researches on interpretation between traditional medicine and systems biology must be focused on personalized medicine since systems biology will have a major impact on future personalized therapeutic approaches.

• Journal of Korean Medical classics
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• v.19 no.3
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• pp.421-426
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• 2006

Objective To learn if there were different characteristics of tongue demonstration between diseases caused by exogenous pathogenic factor and disorder of internal organs. Methods Choosing 3059 cases from 51 medical records of Qing Dynasty, in which 1397 cases were diagnosed as diseases caused by exogenous pathogenic factor and 1110 were disorder of internal organs. Contrasting the constituent ratio of tongue demonstration using chi-square test. Results There were significant deviation between diseases caused by exogenous pathogenic factor and disorder of internal organs in color of tongue, color of fur and quality of fur (p<0.01). Conclusions the characteristics of tongue demonstration in diseases caused by exogenous pathogenic factor were high frequency of bright red tongue, yellow fur, blank fur and dry fur; and which in disorder of internal organs were high frequency of white tongue, thin fur, greasy fur and exfoliative fur.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.337-341
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• 2004

This paper concerns the analytical modeling and dynamic analysis of advanced rotating blade structure implemented by a dual approach based on structural tailoring and viscoelastic materials technology. Whereas structural tailoring uses the directionality properties of advanced composite materials, the passive materials technology exploits the damping capabilities of viscoelastic material(VEM) embedded into the host structure. The structure is modeled as a composite thin-walled beam incorporating a number of nonclassical features such as transverse shear, warping restraint, anisotropy of constituent materials, and warping and rotary inertias. The VEM layer damping treatment is modeled by using the Golla-Mushes-McTavish(GHM) method, which is employed to account for the frequency-dependent characteristic o the VEM. The displayed numerical results provide a comprehensive picture of the synergistic implications of the application of both techniques, namely, the tailoring and damping technology on vibration response of thin-walled beam structure exposed to external time-dependent excitations.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.6 s.237
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• pp.876-888
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• 2005

Tensile properties and fracture toughness of monolithic aluminum, fiber reinforced plastics and glass fiber/aluminum hybrid laminates under tensile loads have been investigated using plain coupon and single-edge-notched specimens. Elastic modulus and ultimate tensile strength of GFMLs showed different characteristic behaviors according to the Al kind, fiber orientation and composition ratio. Fracture, toughness of A-GFML-UD which was determined by the evaluation of $K_{IC}$ and $G_{IC}$ based on critical load was similar to that of GFRP-UD and was much higher than monolithic Al. Therefore, A-GFML-UD presented superior fracture toughness as well as prominent damage tolerance in comparison to its constituent Al. By separating Al sheet from GFMLs after the test, optical microscope observation of fracture zone of GFRP layer in the vicinity of crack tip revealed that crack advance of GFMLs depended on the orientation of fiber layer as well as Al/fiber composition ratio.

• Economic and Environmental Geology
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• v.33 no.5
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• pp.435-442
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• 2000

Although the mummies of Lee Myeong-Jung and his wife who were a member of the Moon family, were buried in similar sites in around 1560, the degree of decay of the dead bodies and antiquities between two people were quite different. This study was focused on the cause of-those differences in terms of engineering geology. Cranular soil found several metered depth around the study site has good drainage ability and such characteristic could be a factor of excellent conservation of dead body. From the physical characteristics of the lime-containing material that is considered to be a barrier from water and air, it was observed that the material around dead body of wife was more compact and denser than that of husband. Such results could be a clear evidence that the lime containing material around dead body of wife was excellent barrier for keeping away from water and air. To investigate those differences of physical characteristics and constituent materials between two lime-containing materials, minerals had to be identified from the two materials. It was revealed that lime-containing material around dead body of wife contains gypsum and more calcite, which could be the reason for better barrier preventing from water and air than those around husband.