• Biomedical Science Letters
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• v.9 no.3
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• pp.123-131
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• 2003

Inflammation appears to have a major role in the development of atherosclerosis. Cyclooxygenase-2 (COX-2) is involved in the inflammatory response via the generation of prostanoids that, in turn, are involved in the production of matrix metalloproteinases (MMPs). This study hypothesized that a vascular infection with cytomegalovirus (CMV) may induce a chronic inflammatory reaction and activated inflammatory cells may express inflammatory mediators such as cyclooxygenase-2 (COX-2) and matrix metalloproteinases-9 (MMP-9). To confirm the hypothesis, the immunohistochemical stains for CMV late antigen, COX-2, MMP-9, macrophage, and T-lymphocyte were performed on CMV-infected atherosclerotic lesions. The immunoreactivity for COX-2 and MMP-9 was evident in all cases of atherosclerosis along with plaques, mainly in macrophages/foamy cells, intimal and medial smooth muscle cells, and endothelial cells of the intima. Within the intima, the increased immunoreactivity for COX-2 and MMP-9 was colocalized to the area stained with CMV late antigen. Sections from control specimens showed no immunoreactivity for CMV late antigen, COX-2 and MMP-9. These data seem to support the hypothesis that CMV may participate in a pathogenetic mechanism for atherogenesis or progression of atherosclerosis.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.3_1spc
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• pp.544-550
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• 2013

A grooved surface with anisotropic wettability was fabricated on a silicon substrate using photolithography, reactive ion etching, and a KOH etching process. The contact angles (CAs) of water droplets were measured and compared with the theoretical values in the Cassie state and Wenzel state. The experimental results showed that the contact area between a water droplet and a solid surface was important to determine the wettability of the water. The specimens with native oxide layers presented CAs ranging from $71.6^{\circ}$ to $86.4^{\circ}$. The droplets on the specimens with a native oxide layer could be in the Cassie state because they had relatively smooth surfaces. However, the CAs of the specimens with thick oxide layers ranged from $33.4^{\circ}$ to $59.1^{\circ}$. This indicated that the surface roughness for a specimen with a relatively thick oxide layer was higher, and the water droplet was in the Wenzel state. From the CA measurement results, it was observed that the wetting on the grooved surface was anisotropic for all of the specimens.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.29 no.4
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• pp.53-63
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• 1997

Most cellulose resources come from the higher plants, but bacteria also synthesize same cellulose as in plants. Many scientists have been widely studied on the bacterial cellulose, the process development, manufacturing, even marketing of cellulose fibers. The bacterial celluloses are very different in its physical and morphological structures. These fibers have many unique properties that are potentially and commercially beneficial. The fine fibers can produce a smooth paper with enchanced its strength property. But there gave been few reports on the mechanical properties of the processing of bacterial cellulose into structural materials. This study were performed to elucidate the mechanical properties of sheets prepared from bacterial cellulose. Also reinforcing effect of bacterial cellulose on the conventional pulp paper as well as surface structures by scanning electron microscopy were discussed. Paper made from bacterial cellulose is 10 times much stronger than ordinary chemical pulp sheet, and the mixing of bacterial cellulose has a remarkable reinforcing effect on the papers. Mechanical strengthes were increased with the increase of bacterial cellulose content in the sheet. This strength increase corresponds to the increasing water retention value and sheet density with the increase of bacterial cellulose content. Scanning electron micrographs were shown that fine microfibrills of bacterial celluloses covered on the surfaces of hardwood pulp fibers, and enhanced sheet strength by its intimate fiber bonding.

• Korean Journal of Materials Research
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• v.16 no.1
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• pp.63-67
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• 2006

The characteristics of the wet-etching of ZnO thin films were investigated using hydrochloric and phosphoric acid solutions as etchants. The etch rate of ZnO films, using highly diluted hydrochloric acid solutions at a concentration of 0.25% in deionized water, was determined to be about 120 nm/min, and linearly increased with increasing the acid concentration, resulting in $1.17{\mu}m/min$ when a 2% HCl solution was used. The surface of ZnO etched by an HCl solution, observed by scanning electron microscopy, showed a rough morphology with a high density of hexagonal pyramids or cones with sidewall angles of about ${\sim}45^{\circ}C$. Moreover, the sidewall angles of the masked area were similar to those of the pyramids on the surface. In comparison, the surface of ZnO etched by a phosphoric acid had a smooth surface morphology. The origin of this difference is from the very initial stage of etching, indicating that the etch-mechanism is different for each solution. Furthermore, when $H_3PO_4$ was added to the HCl aqueous solution, the morphology of the etched surface was greatly enhanced and the sidewall angle was also increased to about $65^{\circ}C$.

• Journal of the korean Society of Automotive Engineers
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• v.6 no.4
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• pp.36-45
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• 1984

The relationship between vehicle driving pattern and fuel consumption in urban area was studied in Seoul along three representative routes using a test car equipped with all the instruments required for recording modes of traffic and measuring fuel consumption. Correlation with idle speed, fuel consumption and CO concentration of car in use was also measured. The average vehicle speed in Seoul was 31.4 km/h and the time spent in different modes was 23.0% in idle mode, 22.5% in acceleration mode, 32.4% in cruising mode and 22.3% in deceleration mode, respectively. Hence, traffic flow was suggested to be relatively smooth. Fuel consumption per unit distance, .phi. was closely related with trip time spent per unit distance, t, and correlation coefficient obtained from the test car was 0.925, and the relationship between .phi. and t was also obtained from the linear regression with the following equation. .phi.=42.87+0.38 t. Idle speed of vehicle in use was mostly adjusted low and cars which were over the permissible standard of CO concentration (4.5%) were 50% or more. As the idle speed decreased, the fuel consumption was decreased, while the CO concentration was increased. Therefore, the decrease of fuel consumption can not be expected with only a decrease in idle speed.

• 한국디지털정책학회:학술대회논문집
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• 2007.06a
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• pp.33-40
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• 2007

The Customs Administration, unlike other administrative service, should respond to constantly changing external environment. The Customs has to actively adapt itself to government policy changes, economic changes and international environment changes to facilitate the flow of trade logistics and maintain trading relations wi th other countries. The purpose of this paper is to explain policy directions of the Korea Customs Service which enforces various policies related to tariff and non-tariff barrier elimination for the trade liberalization while the Korean government is pursuing FTAs on a multi-track basis. This paper aims to seek ways to apply FTA policies to the Korean society and economy in a smooth manner. First of all, this paper examines changes in Customs administration brought by the proliferation of FTAs to such areas as FTA negotiations, import/export management, duties and taxes collection, drawback reduction/exempt ion of duty application area of preferential tariff rate and country of origin management. Then, the paper sets FTA missions of "supporting Customs Administration to lead the new trend of free trade environment" after analyzing the environment changes. To achieve the FTA mission mentioned above, the KCS designated 4 strategies and 40 implementation tasks. The 4 strategies are named "4C Strategies" taking initial letters from Client-oriented, Customized procedures, Cooperation and Constitution. "4C" also refers to Foresee(strategies to foresee the successful establishment of FTA policies) or For C(Customer or Customs). The KCS will continue to create new tasks through various channels and monitor their implementation process, and to help FTA regime successfully take root in Korea.

• Culinary science and hospitality research
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• v.14 no.3
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• pp.178-195
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• 2008

This examination was conducted as follows; 189 copies were coated in total, and demonstratively analyzed by SPSS WIN 15.0 program. The methods used in data for this analysis are as follows; Sensitivity, Reliability, Frequency, Internal consistency, One way ANOVA(Scheffe's examination) Analysis, T-test, etc. The findings of this study are as follows; firstly, it was revealed that respondents who were regular customers of Italian restaurants regarded convenient transportation, property of space, property of pastoral, visibility, and accessibility as importance. This means that Italian restaurant marketers should consider some of factors of location for business with a good view, good parking lot, location at main street, smooth flow of traffic, luxury, atmosphere of freedom, clean area around restaurants, elegant interior of the building, comfortable, luxurious, and deluxe atmosphere, and so on. Secondly, it was revealed that respondents who were regular customers of buffet restaurant either considered the same factors as the Italian restaurants above or regarded those factors less important. This suggests that restaurants should be located on main streets, on trunk roads, and in large-scale residential districts of apartment complex. Thirdly, it was revealed that respondents who were regular customers of traditional restaurants did not consider the locational factors above. This shows that traditional restaurants should be located in nearby customers' houses or their working places, and that marketers should consider focusing on their restaurants' homelike atmosphere, cleanliness, food flavors, and so on.

• The Journal of the Korean dental association
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• v.19 no.7 s.146
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• pp.625-634
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• 1981

A Scanning Electron Microscopic Study of the root surface changes was carried out in advanced periodontal disease. The results obtained were summerized as follow; 1. The root surface of cementoenamel junction of healthy root showed smooth surface, while the root surface of diseased state showed covering of deposits which regareded as a course of calcification. 2. At the mid-portion of the root, the regular cemental projection were observed on the healthy root surface and on the root surface of diseased state, cemental projection showed relatively irregular pattern. 3. On the root surface which consist of wall of periodontal pocket, there were various deposits which could be considered as subgingival calculus, bacterial plaque and epithelial attachment remnant. 4. The bottom area of the pathologic pocket, tearing altered collagen fibers were seen on the root surface. 5. At the apical portion of root surface, calcified fibers ran parallel to the root surface in healthy tooth and the fiber bundles of periodontal ligament were seen in the diseased state.

• Animal cells and systems
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• v.16 no.6
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• pp.479-487
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• 2012

Biological attachment device is optimized in insect legs for attachment onto the variety of natural substrate. We have studied the microstructural characteristics of the tarsal appendages in the ladybug Harmonia axyridis using scanning electron microscopy to reveal the attachment system of their legs. The attachment devices are composed of claws and adhesive pads. The claws are connected with pretarsal segment, and their apical diverged hooks are developed to hold rough substrates. In contrast, the adhesive pads have an adhesive function onto smooth surface. The pads are interspersed at the ventral part of each tarsomere, and are composed of two kinds of hairy setae. The discoid tip seta (DtS) has a spoon-shaped endplate usually with a rounded concave structure, whereas the pointed tip seta (PtS) has a pointed tip, usually with a hooked endplate. While the PtS is broadly localized concentrically on the marginal area of both the proximal and distal pads, the DtS can be seen at the central areas of each adhesive pad except for the hind legs. Our findings demonstrate the presence of the direction-dependence pattern of the fibrillar system as well as a functional modification of the tenent setae to achieve proper contact with almost any kind of substrates.

• Proceedings of the KSR Conference
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• 2004.10a
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• pp.455-460
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• 2004

The Fuel cell Rubber tired Train (FRT), which is now getting the attention as the next generation vehicle with its environment-friendliness, is the transportation for smooth connections of city traffic. It is the revival of the surface-car system with its revaluation of the function and technological development. Accordingly, fixed time operation and high speed driving became possible. FRT is operated together with other vehicles on the regular drive way. While this vehicle can solve the problem of traffic congestion in the urban area, it also can be cost-effective when it is compared to the cost of subway construction. It is also designed to minimize the underground or elevated traffic lane, to introduce the new construction technology, to reduce a term of works, and to cut down the operation cost by unmanned automatic driving system. Furthermore, it is considered as the alternative measure of other transportation due to its potential for the ecological way of speed improvement and the accessability to the disabled, elderly and children by developing the vehicle with folding steps or by building the high boarding platforms. In this research, I concentrated on the user oriented interior design of the FRT to make it passenger-friendly and safe in order to maximize the utilization of the vehicle so that all users including wheelchaired, user with baby carriage, elderly and children can conveniently use this vehicle.