• Fibers and Polymers
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• v.6 no.4
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• pp.322-331
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• 2005

Graduated compression stockings (GCS) have been widely used for the prophylaxis and treatment of venous diseases. Their gradient pressure function largely related to their fabric structure and material properties. By combing fabric physical testing and wear trials, this study investigated the GCSs fabric structure and material properties at different locations along the stocking hoses, and quantitatively analyzed the effects of fabrics on skin pressure longitudinal and transverse distributions. We concluded that, Structural characteristics and material properties of stocking fabrics were not uniform along the hoses, but a gradual variation from ankle to thigh regions, which significantly influenced the corresponding skin pressure gradient distributions; Tensile (WT, EM) and shearing properties (G) generated most significant differences among ankle, knee and thigh regions along the stocking hose, which significantly influenced the skin pressure lognitudinal gradient distribution. More material indices generating significant gradual changes occurred in the fabric wale direction along stocking hose, meaning that materials properties in wale direction would exert more important impact on the skin pressure gradient performances. And, the greater tensibility and smoother surface of fabric in wale direction would contribute to put stocking on and off, and facilitate wearers' leg extension-flexion movements. The indices of WT and EM of stocking fabrics in series A have strong linear correlations with skin pressure lognitudinal distribution, which largely related to their better performances in gradual changes of material properties. Skin pressure applied by fabric with same material properties produced pronounced differences among four different directions around certain cross-sections of human leg, especially at the ankle region; and, the skin pressure magnitudes at ankle region were more easily influenced by the materials properties, which were considered to be largely related to the anatomic structure of human leg.

• Membrane Journal
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• v.21 no.3
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• pp.236-246
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• 2011

In this study, we used prepared a cylindrical module consisting 100 hollow fibers of commercialized (hydrophobic) polyethylene membrane of $0.4{\mu}m$ pore size and systematically studied performance of direct contact membrane distillation (DCMD) and sweep gas membrane distillation (SGMD) in terms of variation of permeate flux and salt rejection with respect to temperature drop across the membrane, salt concentrations in feed, and flow rates of cooling water and sweep gas. SGMD was regarded as DCMD with a sweep gas layer between permeate-side membrane surface and cooling water. Sweep gas flow decreases the permeate flux from that of DCMD by providing an additional gas-layer resistance. We compared DCMD and SGMD performance by using mass balance with a fitting parameter (${\omega}$), indicating fraction of permeate flow rate.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.1
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• pp.193-202
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• 2008

This paper investigates experimentally the confining effect, strengthening capacity and rebound rate of sprayed Fiber-Reinforced-Polymer (SFRP). From the method, resin and chopped fibers are sprayed separately from the nozzle with high pressure, and then they are attached to the concrete surface, so structure could be repaired. To evaluate the strengthening effect of sprayed FRP, cylindrical specimens and beam specimens were strengthening with SFRP. As main material of FRP, glass fiber and polyester resin are used. To investigate the optimum condition of sprayed FRP, the effects of fiber length, coating thickness, fiber volume ratio and concrete strength were examined. Capacities of sprayed FRP method were also compared to the FRP sheet method. In case of the sprayed FRP, rebound rate is important parameter considering economical efficiency and constructibility, so rebound rate of was discussed. From the test results, optimum conditions of sprayed FRP were determined. SFRP method showed superior strengthening capacities than FRP sheet method.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.5
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• pp.754-764
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• 2010

Most silk fabrics are produced only after the degumming process to make the best use of the properties and have restricted silk processing that do not hinder their performance. However, considering the highly increased preference for natural fibers and the shortage of raw silk, high-quality upgraded silk product functions are required by the development of a processing technology and a good design. This study analyzes the changes with the samples by the functional finish such as softening finishing, wash and wear, tannin weighting by measuring the objective hand of scoured silk and three finished ones using KES-FB. As a result, the change of objective hand of finished silk fabrics that improves functionality was analyzed and compared. The increase of KOSHI after the finish became stiffer show that the silk fabric samples are appropriate for summertime clothes with the retention of a certain clothing climate for the body. The stiffness of finished fabrics for the normal had a closer relationship with the density of fabrics than the type of finishing. The samples (after the softening finishes) maintain better elasticity according to the properties of the softener and the finishing agent. Although the specimens of this study were thin fabrics, their elasticity against compression increased after the softening finishes and became softer than degummed silk. The surface properties of georgette were changed by all types of finishing.

• Applied Microscopy
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• v.33 no.4
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• pp.325-333
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• 2003

Fine structural characteristics of the heart tube and its cardiac muscle cells in spider, Araneus ventricosus are investigated by both of scanning and transmission electron microscopes. The heart tube of the spider is extended mid-dorsally along the anterior part of the abdomen, and is consisted of the thin outer layer of connective tissue (epicardium) and the thick muscle layer (myocardium). The myocardium in the spider has a typical fanlike spiral structure toward anterior part put across between the muscle fibers. Therefore, it did not give rise to the intima, and muscle cells are in direct contact to the hemolymph. The heart tube appeared to be three pairs of ostia and numerous hemocytes accumulated at the inner surface of the myocardial layer. Among several kinds of the hemocytes, the oenocytoids are the most predominant hemocytes accumulated along the myocardial folds which stretched toward heart lumen. The heart muscle cells are cross striated, branched, and multinucleated. They contain a lot of mitochondria, which provide for the continuous energy demands of the heart. Thread-like ganglion on the dorsal side of the heart tube gives off axons that innervate the heart muscle cells.

• Journal of the Korean Wood Science and Technology
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• v.42 no.2
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• pp.163-171
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• 2014

Environmental issues about indoor air quality have been increased and focused on volatile organic compounds (VOCs) caused cancer, asthma, and skin disease. Reducing VOCs has been attempted in many different methods such as using environmentally friendly materials and air cleaner or purifier. Charcoal is well known material for absorbing VOCs. Therefore, carbonized board from medium density fiberboard has been developed. We assumed that the source of carbonized boards can be any type of wood-based panels. In this study, carbonized boards were manufactured from oriented strand board (OSB) at 400, 600, 800, and $1000^{\circ}C$. Each carbonized OSB (c-OSB) was evaluated and determined physiomechanical characteristics such as exterior defects, dimensional shrinkage, modulus of elasticity, and bending strength. No external defects were observed on c-OSBs at all carbonizing conditions. As carbonizing temperature increased, less porosity between carbonized wood fibers was observed by SEM analysis. The higher rate of dimensional shrinkage was observed on c-OSB at $1000^{\circ}C$ (66%) than c-OSB at 400, 600, and $800^{\circ}C$ (47%, 58%, and 63%, respectively). The densities of c-OSBs were lower than original OSB, but there was no significant different among the c-OSBs. The bending strength of c-OSB increased 1.58 MPa (c-OSB at $400^{\circ}C$) to 8.03 MPa (c-OSB at $1000^{\circ}C$) as carbonization temperature increased. Carbonization temperature above $800^{\circ}C$ yielded higher bonding strength than that of gypsum board (4.6 MPa). In conclusion, c-OSB may be used in sealing and wall for decorating purpose without additional artwork compare to c-MDF which has smooth surface.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.36 no.12
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• pp.1591-1597
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• 2012

Adherend samples were made from unsaturated polyester and woven and mat glass fibers by the hand layup and vacuum methods. The mechanical properties of the adhesive, composite adherends, and terminal-joint and secondary-joint specimens were determined experimentally. Combinations of the experiment results and the bonding theory were used in this study. The maximum and average shear stresses were calculated based on the maximum tensile force and geometry parameters of the joint specimens. The results of the maximum and average shear stresses were compared and evaluated for six joints. The results showed that the grinding and grind/acetone joint had the highest strength among three types of terminal-joints. Similarly, the mat-mat and mat-woven joints had the highest strength among three types of secondary-joints with the same value. Conversely, no treatment and woven-woven bonding had very low strength. In each case, failure occurred always at two ends and then moved toward the middle area of the overlap length.

• Journal of the Korean Society for Heat Treatment
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• v.7 no.3
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• pp.169-174
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• 1994

The reaction layer formed at interface between matrix and fiber has significant effects on the mechanical properties and behaviors of deformation m FRM. In this study, the mechanical properties and interfacial behaviors according to surface finishing on the fibers and according to heat treatment in FRM were investigated. FRM was fibricated by diffusion bonding method. In W/Al alloy composite and W/Al composite, W of which was coated with $WO_3$, the heat treatment was carried out thermal cycling method from 373K to 673K. In W/Al composite, W of which was coated with $WO_3$, growth of interface layer was hardly occured in spite of the increasing various thermal cycles. It was exhibited that oxidized W/Al composite were higher strength than non-oxidezed W/Al composite with the increasing thermal cycles. The compounds of fiber/matrix interface were analyzed into $WAl_{12}$, $WAl_7$, and $AlWO_3$, respectivly. Therefore the interfacial compounds of fiber/matrix seriously affected the mechanical properties and behaviors of deformation in FRM.

• Fashion & Textile Research Journal
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• v.18 no.2
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• pp.244-251
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• 2016

Viscose rayon filament fabrics have been called 'artificial silk' and beloved as summer clothing materials for a long time in Korea. This is because the viscose rayon filament fabrics reveals glossy surface and cool touch feeling compared to other conventional fabrics composed of staple fibers. Therefore, we tried to prepare the higher value added viscose rayon filament fabrics for summer textile products. In this study, we applied gallnut extract to the viscose rayon filament fabric to develop summer fabrics with natural color and multi-functions such as antibacterial and antioxidant properties. This process also pursue eco-friendly and multi-functional fabric finishing from the natural material "gallnut". In addition, various pre-treatment with cationizer, chitosan, or chito-oligomer was applied to the finishing process to improve the finishing efficacy and durability. Consequently, it was found that the active component of gallnut extract was successfully incorporated to the viscose rayon filament fabric through a pad-dry-cure process. And, the treated viscose rayon filament fabrics showed excellent antibacterial and antioxidant properties. Therefore, it was expected that the rayon filament fabrics treated by gallnut extract could be used as effective summer fabrics preventing the growth of bacteria and skin ageing as well as providing cool touch feeling. However, the pre-treatments were not that meaningful on the functionalities but effective on coloring.

• Korean Journal of Veterinary Research
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• v.45 no.4
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• pp.593-599
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• 2005

An abattoir study on the abdominal fat necrosis in adult cattle was performed pathologically. Grossly, masses of fat necrosis were leekgreen in colour, lobulated on the cut surface, and saponificated in the texture. These necrotic adipose tissues infiltrated usually into neighboring parenchymal organs including intestines and pancreas, leading to fibrosis or atrophy of them. Histopathologically, necrotic fat cells contained acidophilic, opaque, amorphous substance or basophilic fibrillar or granular minerals in their cytoplasms. The lesions of fat necrosis were divided by fibroconnective tissue. With increase of the severity, necrotic fat cells fused each other and then formed fat cysts. In this severe lesion, necrotic fat cells were partialy or completely replaced by macrophages. Multinucleated giant cells were scattered in this lesion. Interestingly, small artery in the lesion of fat necrosis revealed severe thickening of internal elastic membrane. Severe fibrosis was observed in or between the outer longitudinal and inner circular muscular externas causing segregation, degeneration and necrosis of muscle fibers. The nerve cells of Auerbach's and Meissner's plexuses surrounded by fibrosis were degenerated or necrotic. In addition, necrotic fat cells infiltrated into the pancreas, resulting in pancreas atrophy. From these results, it is speculated that fat necrosis might compromise intestinal movement due to necrosis of muscular externa and ganglion cells of Auerbach's and Meissner's plexuses.