• Journal of Physiology & Pathology in Korean Medicine
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• v.24 no.5
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• pp.807-813
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• 2010

Impairment of balance between bone-resorbing osteoclasts and bone-forming osteoblasts result in bone disease. Especially, increased osteoclast formation and activity are responsible for bone diseases such as osteoporosis, rheumatoid arthritis, periodontal disease. Natural metabolites of plants have recently received much attention as an alternative tools for the development of novel therapeutic strategy. The aim of this study was to search the natural products to inhibit osteoclast differentiation and was to evaluate of its mechanism. Water extract of Gastrodia elata Blune significantly inhibited receptor activator of nuclear factor-κB ligand (RANKL)-induced osteoclast differentiation in bone marrow macrophages (BMMs) in a dose dependent manner. However, water extract of Gastrodia elata Blune did not affect cytotoxicity when compared with control. The mRNA expression of c-Fos, NFATc1, and TRAP induced by RANKL was inhibited by water extract of Gastrodia elata Blune treatment. Also, water extract of Gastrodia elata Blune inhibited the protein expression of c-Fos and NFATc1 expression in BMMs treated with RANKL. Water extract of Gastrodia elata Blune suppressed the phosphorylation of p38 induced by RANKL. In general, RANKL considerably inhibited the expression level of Id2 and MafB known as negative regulators of osteoclastogenesis, but RANKL did not inhibit Id2 and MafB expression in BMMs when it was co-treated with Gastrodia elata Blune. Taken together, these results suggest that Gastrodia elata Blune may be a useful drug in the treatment of bone-related disease.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.10
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• pp.186-191
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• 2000

We use so many plastic products in everyday. Because polymer materials have a lot of merits including low cost and easiness of forming, they are widely using at many manufacturing industries. Microcellular foaming process appeared at MIT in 1980's to save a quantity of material and increase mechanical properties. The information about the thickness of cavity plays an important role in appling microcellular foaming process to the conventional injection molding process. It is essential to make an effective foam. The goal of this research is to measure the relation between the change of cavity's thickness and foaming magnitude made after inserting a gas. R/t is a conception that indicate proportion between radius and thickness of cavity in mold system. By means of SEM observation of side surface of cavity sample, foaming magnitude of cavity is mold system. By means of SEM observation of side surface of cavity sample, foaming magnitude of polymer in microcellular foaming process is decreasing gradually as the value of R/t is increasing. The proposed foaming magnitude changes data of polymer in relation to mold system can be applied in more extensive injection molding process, such as optimum design of mold for microcellular foaming process.

• Transactions of Materials Processing
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• v.16 no.7
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• pp.509-515
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• 2007

As the springback of sheet metal during unloading may cause deviation from a desired shape, accurate prediction of springback is essential for the design of sheet stamping operations. When considering the case of a sheet metal being bent to radius $\rho$ that is such that the maximum stress induced exceed the elastic limit of the material, plastic strain in the outer surface will occur and the material will take a permanent set: but since, on removing the bending moment, the recovery of the material is not uniform across the thickness, springback will occur and the radius $\rho$ will not be maintained. Furthermore, when a tensile load being applied to each end of specimen, the tensile stress due to bending is increased and the compressive stress is decreased or cancelled and eventually the whole specimen may be in varying degree of tension. On the removal of the applied load the specimen loses its elastic strain by contracting around the contour of the block, the radius $\rho$ will be determined by the residual differential strain. Therefore in this study the springback is analytically estimated by the residual differential strains between upper and lower surfaces of greatest radius after elastic recovery, and a springback model based on the bending moment is also analytically derived for comparison purpose.

• Journal of the Korean Society of Costume
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• v.26
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• pp.233-250
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• 1995

The purpose of this research is to open new horizon in the plastic art centering the clothings, to examine the characteristics of the clothing style of Surrealism closely which is being lighted up again newly in the recent culture that is in a state of flux, and futher to contribute to the cre-ation of future clothes by analyzing Surrealism once again which is considered to have affected most in the aspects of idea and technique from the era of modernism to the era of post modern-ism, to understand and develop the relation of modern style of paintings and clothing which consist of many complicated and diverse elements. As for the method of research, after analyzing the formation and characteristics of painting style of Surrealism, painting style of Surrealism, painting style of Surrealism were classified largely into D paysement and Automatism, which were then reviewed. And the characteristics of fashion style of Surrealism were compared and analyzed with painting style of Surrealism, for this, fashion of Surrealism dur-ing recent five years from 1990 to 1994, among the fashion from Pr t- -Porter concentrated re-view was made for the ones made public at Paris-London Collections. By the result observed through this research, the trompe-l'oeil double image technique of many clothes created by E. Schiaparelli who was strongly influenced by Surrealism in 1930s were succeeded with its inspiration of Surrealism by the radical fashion designers recently and we were able to know that it is being created again by fresh senses. Followings are the discussions on homogenity of the characteristics of fashion style of Surreal-ism with the painting style of Surrealism Therefore if we analyze the characteristics of fashion style of Surrealism, Automatism ex-pression style which takes out only image borrowing the power of unconsciousness, instead of factual transposition, is forming the main cur-rent after 1990s. We can find the fashion style of this Surrealism appear persistently, entirely irrel-evant to the silhouettes of 20th century.

• Progress in Medical Physics
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• v.2 no.2
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• pp.129-139
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• 1991

The method of etching tracks in PN-3 dosimeter has been applied to tracks of recoil protons from a neutron source. Both the etch and the detection response of PN-3 has been studied as a function of etched-track diameters against various parameters. We could obtain very useful informations about charge, energy, and mass of particles and the relationship between the track etching rate and the track forming procedure in order to analyze the particle recorded in the solid state track detector. The best etching condition could be found by means of changing the etching circumstances for various energies and particles in order to detect the charged particle accurately. It could be influenced widely that the polymer plastic detector could develep the detecting technique for the low energy level neutron and could be used as a neutron dosimeter in the radiation field such as the nuclear power station, the medical institute and the nondtructive testing institute.

• The Journal of the Korea Contents Association
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• v.18 no.2
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• pp.290-300
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• 2018

The point of discovering a new technique using colored glass and clay is to improve the existing inconveniences, which is compatible with the mutual physical property of ceramics clay and glass. It is easy to express the decoration of colored glass in vertical ceramics, but the aesthetic expression is limited due to the rust flowing down on horizontal ceramics. So the point is the discovery of a new expressive method that do not melt down in vertical objects. A new technique is to crush finely and dilute the colored glass using clay, and brushing it to the wall. Additionally, inlaid technique and paste brush technique were applied to further enhance aesthetic end. The plastic method is oxidation and reduction, and the coloration was different due to the plasticity method. Particularly, partial cutting of engraved color glass leads to forming gray-line soft gradation. This effect will be good to apply to production of work and industrial ceramics.

• Tunnel and Underground Space
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• v.14 no.4
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• pp.248-260
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• 2004

Damage in brittle rock due to stress increase starts from initiation of microcracks, and then results in failure by forming macro failure planes due to propagation and coalescence of these discrete cracks. Conventionally, continuum approaches using macro-failure criteria or a number of elasto-plastic models have been major solution to implement rock damage and failure. However, actual brittle failure processes can be better described in phenomenological approach if initiation and propagation of discrete fractures are explicitly considered. This study presents damage and failure process of rock using a boundary element code, FRACOD, which has been developed to model fracturing process of rocks. Through a series of numerical uniaxial compressive tests, the feasibility of the developed model was verified, and realistic rock failure process was reproduced considering scale effects in rocks. In addition, the fracturing process and the corresponding rock damage in the vicinity of deep shaft in rock mass were presented as an application of this approach. This approach will be expected to contribute to finding better engineering solutions for the analysis of stability problems in brittle rock masses.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.457-460
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• 2000

Injection molding is the most widely used process for the industrial forming of plastic articles. During an injection molding process of composites, the fiber-matrix separation and fiber orientation are caused by the flow of molten polymer/fiber mixture. As a result, the product tends to be nonhomogeneous and anisotropic. Hence, it is very important to clarify the relations between separation·orientation and infection molding conditions. So far, there is no research on the measurement of fiber orientation using image processing. In this study, the effects of fiber content ratio and molding condition on the fiber orientation-angle distributions are studied experimentally. Using the image processing method, the fiber orientation distribution of welding parts in injection-molded products is assessed. And the effects of fiber content and injection mold shapes on the fiber orientation in case of fiber reinforced polymeric composites are studied. experimentally.

• Steel and Composite Structures
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• v.27 no.3
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• pp.337-353
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• 2018

In previous weak-axis moment connection tests, brittle fracture always initiated near the edge of the beam flange groove weld due to force flow towards the stiffer column flanges, which is the opposite pattern as strong-axis moment connections. As part of the China NSFC (51278061) study, this paper tested two full-scale novel weak-axis reduced beam section moment connections, including one exterior frame connection specimen SJ-1 under beam end monotonic loading and one interior frame joint specimen SJ-2 under column top cyclic loading. Test results showed that these two specimens were able to satisfy the demands of FEMA-267 (1995) or ANSI/AISC 341-10 (2010) without experiencing brittle fracture. A parametric analysis using the finite element software ABAQUS was carried out to better understand the cyclic performance of the novel weak-axis reduced beam section moment connections, and the influence of the distance between skin plate and reduced beam section, a, the length of the reduced beam section, b, and the cutting depth of the reduced beam section, c, on the cyclic performance was analyzed. It was found that increasing three parametric values reasonably is beneficial to forming beam plastic hinges, and increasing the parameter a is conducive to reducing stress concentration of beam flange groove welds while increasing the parameters b and c can only reduce the peak stress of beam flange groove welds. The rules recommended by FEMA350 (2000) are suitable for designing the proposed weak-axis RBS moment connection, and a proven calculation formulation is given to determine the thickness of skin plate, the key components in the proposed weak-axis connections. Based on the experimental and numerical results, a design procedure for the proposed weak-axis RBS moment connections was developed.

• Parasites, Hosts and Diseases
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• v.48 no.4
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• pp.335-338
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• 2010

Maritrema spp. (Digenea: Microphallidae) are parasites of birds, but have not been found in the Republic of Korea. In this study, metacercariae of Maritrema sp. were discovered in the Asian shore crab, Hemigrapsus sanguineus, caught in the mud-flats of Jebu-do, Hwasung-gun, Gyeonggi-do, and the adult flukes were confirmed by experimental infection into mice. Based on the symmetric ribbon-like vitellarium, adult flukes of Maritrema sp. were identified, but did not belong to previously described species in terms of the following morphologic characteristics: ceca reaching to the lateral wall at the anterior border of the ovary; ventral sucker larger than oral sucker; a prominent metraterm; and vitellarium forming a complete ring. Hence, we named this microphallid M. jebuensis n. sp. after the island where the second intermediate hosts were collected. From this study, it has been shown that Maritrema sp. is distributed in Korea and transmitted by the Asian shore crab, H. sanguineus.