• Archives of design research
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• v.16 no.4
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• pp.185-196
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• 2003

The demand for an environment-friendly transportation system, equipped with low energy consumption, and low-or zero-pollution has been on the increase since the beginning of the World Trade Organization era. Simultaneously, the consistent growth of high-speed tram technology, combined with market share, has sparked a fierce competition among technologically-advanced countries like France, Germany, and Japan in an effort to keep the lead in high-speed train technology via extensive Research and development(R＆D) expenses. These countries are leaders in the race to implement the next-generation transportation system, build intercontinental rail way networks and export the high-speed train as a major industry commodity. The need to develop our own(Korean) 'high-speed train' technology and its core system technology layouts including original technology serves a few objectives: They boost the national competitive edge; they develop an environmental friendly rail road system that can cope with globalization and minimize the social and economic losses created by the growing traffic-congested delivery costs, environment pollution, and public discomforts. In turn, the 'G7 Project-Development of High Speed Railway Technology' held between 1996 and 2002 for a six-year period was focused on designing a domestic train capable of traveling at a speed of 350km/h combined and led to the actual implementation of engineering and producing the '2000 high-speed train:' This paper summarizes and introduces one of the G7 Projects-specifically, the design segment achievement within the development of train system engineering technology. It is true that the design aspect of the Korean domestic railway system program as a whole was lacking when compared with the advanced railroad countries whose early phase of train design emphasized the design aspect. However, having allowed the active participation of expert designers in the early phase of train design in the current project has led to a new era of domestic train development and the implementation of a way to meet demand flexibly with newly designed trains. The idea of a high-speed train in Korea and its design concept is well-conceived: a faster, more pleasant, and silent based Korean high-speed train that facilitates a new travel culture. A Korean-type of high-speed train is acknowledged by passengers who travel in such trains. The Korean high-speed prototype train has been born, combining aerodynamic air-cushioned design, which is the embodiment of Korean original design of forehead of power car minimized aerodynamic resistance using a curved car body profile, and the improvement of the interior design with ergonomics and the accommodation of the vestibule area through the study of passenger behavior and social culture that is based on the general passenger car.

• Journal of Chest Surgery
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• v.31 no.11
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• pp.1023-1030
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• 1998

Background: Calcific degeneration limits durabilities of the bioprosthetic tissues implanted in the human body. The direct coupling sulphonated polyethyleneoxide(PEO-SO3) to the bioprosthetic tissues after glutaraldehyde(GA) fixation and the removal of residual aldehyde groups from the tissues can augment the effect of calcification-resistance. Materials and methods: To study the anti-calcification effect by PEO-SO3 modification and the removal of the residual aldehyde groups of tissues, surface modified bovine pericardia(BP-PEO-SO3) were preserved in aseptic saline to wash out GA(saline group) and 0.65% GA solution(GA group). And then above two groups and PERIGUARD (Bio-vascular. Co.) (product group) were evaluated with respects to calcium contents and microscopic findings using in vivo implantation models at carotid and femoral artery and peritoneum of 8 adult dogs. Results: In the tissues retrieved from carotid artery, calcium content was significantly decreased in saline group than in other two groups(saline; 2.89±0.31 vs. GA; 6.14±1.08 vs. product; 22.82±5.00 mg/g of dried tissue; p<0.05). In the tissues retrieved from femoral artery and peritoneum, calcium amount was also decreased in saline group than in other two groups, but not reached the significant difference between groups. On the other hand, the pathologic findings of pericardial tissues showed marked destructuction in GA group compared to the other two groups. Conclusions: In this study, covalently PEO-SO3 bound to bovine pericardium decreased calcifications and the anti-calcification effect of BP-PEO-SO3 could be augmented by the washing out the residual aldehyde groups using saline after GA fixation. Conclusively, the PEO-SO3 modified bovine pericardium is highly resistant to calcification and can be useful for the development of calcification-resistant cardiovascular patches and valves.

• Journal of Broadcast Engineering
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• v.10 no.1 s.26
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• pp.43-56
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• 2005

In the existing broadcasting environment, it is not easy to serve the bi-directional service between a broadcasting server and a TV audience. In the uni-directional broadcasting environments, almost TV programs are scheduled depending on the viewers' popular watching time, and the advertisement contents in these TV programs are mainly arranged by the popularity and the ages of the audience. The audiences make an effort to sort and select their favorite programs. However, the advertisement programs which support the TV program the audience want are not served to the appropriate audiences efficiently. This randomly provided advertisement contents can occur to the audiences' indifference and avoidance. In this paper, we propose the target advertisement service for the appropriate distribution of the advertisement contents. The proposed target advertisement service estimates the audience's profile without any issuing the private information and provides the target-advertised contents by using his/her estimated profile. For the experimental results, we used the real audiences' TV usage history such as the ages, fonder and time of the programs from AC Neilson Korea. And we show the accuracy of the proposed target advertisement service algorithm. NDS (Normalized Distance Sum) and the Vector correlation method, and implementation of our target advertisement service system.

• Current Research on Agriculture and Life Sciences
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• v.3
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• pp.129-150
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• 1985

The present investigation was conducted to provide a systematic approach necessary to establish an integrated insect pest management program of barley in Korea. Some ecological surveys on insect pests of barley have been undertaken at the field of Experimental Station, Ky$\check{o}$ngbuk Provincial Office of Rural Development as a fixed point survey area, and at 23 localities for round survey throughout southern and central Korea from 1983 to 1984. Previously known insects injurious to barley in Korea were revised and the population dynamics of 10 dominant harmful species were analyzed according to either 24 localities or 25 cultivars respectively by using several sampling methods of net sweeping, black light traps, yellow water pan traps and visual counting. As the results, a total of 94 species belonging to 77 genera under 32 families are known to be injurious to barley, among them 20 species are newly added here. In the population density level, the dominant species were disclosed as Laodelphax striatellus (43.1 %), Macrosiphum avenae(27.0 %), Rhopalosiphum padi(6.5 %), R. maidis(5.4 %), Psammolettix strialus(2.7 %), Chlorops oryzae(2.2 %), Agromyza albipennis(2.1 %) Phyllotreta nemorum(1.4 %), Chaetoenema cylindrica(1.0 %), Dolycoris baccarum(1.0 %) in order. For the general abundance of major insect pests, it was highest in the cultivar P'aldal whereas lowest in Milyang #22. There were tendencies that Psammotettix striatus, Dolycoris baccarum, Phyllotreta nemorum and Chaetocnema cylindrica represented a maximum increase in the beginning of June, while Chlorops oryzae and Agromyza albipennis showed in the middle of May but aphids were in the end of May. In the dominance of natural enemies, Nabis stenoferus occupied 21.4 % and Propylaea japonica 9.6 %.

• Clinical and Experimental Pediatrics
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• v.52 no.10
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• pp.1109-1118
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• 2009

Purpose : Metabolic syndrome (MS), characterized by obesity and insulin resistance, elicits risk factors such as hyperlipidemia, hypertension, and glucose intolerance with additive effects on atherosclerosis, leading to cardiovascular diseases. The purposes of this study were to evaluate the prevalence of MS among overweight and obese adolescents and to investigate the impact of obesity on the cardiovascular system. Methods : In all, 684 adolescents were included in the study. Blood pressure, body mass index (BMI), fasting blood glucose, total cholesterol, triglyceride, low-density-lipoprotein (LDL)-cholesterol, high-density-lipoprotein (HDL)-cholesterol, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and high-sensitive C-reactive protein (hs-CRP) were measured in the patients with a BMI of >85 percentile. Brachial-ankle pulse wave velocity (BaPWV) and ankle brachial index were measured using Vascular Profiler (VP)-1000. Results : MS was confirmed in 19.5% of the overweight and obese adolescents and 50.8% of the obese adolescents. The systolic and diastolic blood pressure, height, weight, fat mass, %fat, BMI, obesity index, and waist circumference were higher in the overweight and obese adolescents with MS. Moreover, the triglyceride, AST, ALT, and hs-CRP levels were higher, whereas HDL-cholesterol level was significantly lower in this group. The overweight and obese adolescents with MS showed shorter diastolic and systolic times, higher heart rate and BaPWV, and longer E-wave deceleration time by echocardiography. Conclusion : Overweight and obese adolescents showed characteristic MS features such as hypertension and hyperlipidemia. Thus, obese adolescents predisposed to MS should be provided early treatment for obesity.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.3
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• pp.253-261
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• 2005

Catalytic wet oxidation of ppm levels of trichloroethylene (TCE) in water has been conducted using $TiO_2$-supported cobalt oxides at a given temperature and weight hourly space velocity. 5% $CoO_x/TiO_2$ might be the most promising catalyst for the wet oxidation at $36^{\circ}C$ although it exhibited a transient behavior in time on-stream activity. Not only could the bare support be inactive for the wet decomposition reaction, but no TCE removal also occurred by the process of adsorption on $TiO_2$ surface. The catalytic activity was independent of all particle sizes used, thereby representing no mass transfer limitation in intraparticle diffusion. Characterization of the $CoO_x$ catalyst by acquiring XPS spectra of both fresh and used Co surfaces gave different surface spectral features of each $CoO_x$. Co $2p_{3/2}$ binding energy of Co species exposed predominantly onto the outermost surface of the fresh catalyst appeared at 781.3 eV, which is very similar to the chemical states of $CoTiO_x$ such as $Co_2TiO_4$ and $CoTiO_3$. The spent catalyst possessed a 780.3 eV main peak with a satellite structure at 795.8 eV. Based on XPS spectra of reference Co compound, the TCE-exposed Co surfaces could be assigned to be in the form of mainly $Co_3O_4$. XRD measurements indicated that the phase structure of Co species in 5% $CoO_x/TiO_2$ catalyst even before reaction is quite comparable to the diffraction lines of external $Co_3O_4$ standard. A model structure of $CoO_x$ present on titania surfaces would be $Co_3O_4$, encapsulated in thin-film $CoTiO_x$ species consisting of $Co_2TiO_4$ and $CoTiO_3$, which may be active for the decomposition of TCE in a flow of water.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.1041-1048
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• 2016

Biofilm cells and viable but non-culturable (VBNC) state may play a role in the survival of Campylobacter jejuni under unfavorable environmental conditions. The objective of this study was to investigate the behavior of C. jejuni biofilm cells and VBNC cells on smoked duck. The transfer of C. jejuni biofilm cells to smoked duck and its ability to resuscitate from biofilm and VBNC cells on smoked duck was investigated. Transfer experiments were conducted from C. jejuni biofilm cells to smoked duck after 5 min, 1 h, 3 h, and 24 h contact at room temperature, and the efficiency of transfer (EOT) was calculated. In addition, smoked duck was inoculated with C. jejuni biofilm and VBNC cells and then stored at 10, 24, 36, and $42^{\circ}C$ to examine the cells' ability to resuscitate on smoked ducks. The 5 min contact time between C. jejuni biofilm cells and smoked duck showed a higher EOT (0.92) than the 24 h contact time (EOT=0.08), and the EOT decreased as contact time increased. Furthermore, C. jejuni biofilm cells on smoked duck were not recovered at 10, 24, and $36^{\circ}C$, and C. jejuni VBNC cells were not resuscitated at $42^{\circ}C$. Although the resuscitation of C. jejuni biofilm and VBNC cells was not observed on smoked duck, microbial criteria of C. jejuni is needed in poultry and processed poultry products due to risk of its survival and low infectious dose.

• The Journal of Korean Academy of Prosthodontics
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• v.47 no.1
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• pp.53-60
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• 2009

Statement of problem: At present, as the esthetic demands are on the increase, there are many ongoing studies for tooth-colored post and cores. Most of them are about fiber post and prefabricated zirconia post, but few about one-piece milled zirconia post and core using CAD/CAM (computer-aided design/computer-aided manufacturing) technique. Purpose: The objective of this study was to compare microleakage of endodontically treated teeth restored with three different tooth-colored post and cores. Material and methods: Extracted 27 human maxillary incisors were cut at the cementoenamel junction, and the teeth were endodontically treated. Teeth were divided into 3 groups (n=9); restored with fiber post and resin core, prefabricated zirconia post and heat-pressed ceramic core, and CAD/CAM milled zirconia post and core. After the preparation of post space, each post was cemented with dual-polymerized resin cement (Variolink II). Teeth were thermocycled for 1000 cycles between $5-55^{\circ}C$ and dyed in 2% methylene blue at $37^{\circ}C$ for 24 hours. Teeth were sectioned (bucco-lingual), kept the record of microleakage and then image-analyzed using a microscope and computer program. The data were analyzed by one-way ANOVA and Scheffe's multiple range test (${\alpha}=0.05$). Results: All groups showed microleakage and there were no significant differences among the groups (P>.05). Prefabricated zirconia post and heat-pressed ceramic core showed more leakage in dye penetration at the post-tooth margin, but there was little microleakage at the end of the post. Fiber post and resin core group and CAD/CAM milled zirconia post and core group indicated similar microleakage score in each stage. Conclusion: Prefabricated zirconia post and heat-pressed ceramic core group demonstrated better resistance to leakage, and fiber post and resin core group and CAD/CAM milled zirconia post and core group showed the similar patterns. The ANOVA test didn't indicate significant differences in microleakage among test groups. (P>.05)

• Journal of the Korean Electrochemical Society
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• v.20 no.1
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• pp.7-12
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• 2017

Using a precursor of $LiNi_{0.6}Co_{0.2}Mn_{0.2}O_2$ as a starting material, a surface-modified cathode material was obtained by coating with KCl, where the added KCl reduces residual Li compounds such as $Li_2CO_3$ and LiOH, on the surface. The resulting electrochemical properties were investigated. The amounts of $Li_2CO_3$ and LiOH decreased from 8,464 ppm to 1,639 ppm and from 8,088 ppm to 6,287 ppm, respectively, with 1 wt% KCl added $LiNi_{0.6}Co_{0.2}Mn_{0.2}O_2$ that had been calcined at $800^{\circ}C$. X-ray diffraction results revealed that 1 wt% of KCl added $LiNi_{0.6}Co_{0.2}Mn_{0.2}O_2$ did not affect the parent structure but enhanced the development of hexagonal crystallites. Additionally, the charge transfer resistance ($R_{ct}$) decreased dramatically from $225{\Omega}$ to $99{\Omega}$, and the discharge capacity increased to 182.73mAh/g. Using atomic force microscopy, we observed that the surface area decreased by half because of the exothermic heat released by the Li residues. The reduced surface area protects the cathode material from reacting with the electrolyte and hinders the development of a solid electrolyte interphase (SEI) film on the surface of the oxide particles. Finally, we found that the introduction of KCl into $LiNi_{0.6}Co_{0.2}Mn_{0.2}O_2$ is a very effective method of enhancing the electrochemical properties of this active material by reducing the residual Li. To the best of our knowledge, this report is the first to demonstrate this phenomenon.

• Tuberculosis and Respiratory Diseases
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• v.60 no.3
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• pp.314-320
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• 2006

Background : The overall response (20-30%) to chemotherapy in non-small cell lung cancer (NSCLC) is quite poor. Heme oxygenase-1 (HO-1) is the rate-limiting enzyme in heme degradation. There is increasing evidence suggesting that the induction of HO-1 might have an important protective effect against oxidative stress including cisplatin containing chemotherapy. This study retrospectively investigated the relationship between HO-1 expression and the response to chemotherapy containing cisplatinin advanced NSCLC patients. Material and Methods : The medical records including the responses to chemotherapy of fifty nine cases were evaluated retrospectively, and the tissue samples of these patients were immunohistochemically stained for HO-1. Results : Forty three of the fifty nine patients(72.8%) showed positive staining for HO-1 in their cancer tissues. There was no significant difference according to the cell type, stage and tumor size. In addition, there was no correlation between HO-1 expression and the responses to chemotherapy. Conclusion : HO-1 expression in tumor tissue dose not predict the response to cisplatin containing chemotherapy in advanced NSCLC. Further prospective studies with a larger number of patients will be needed to confirm these results.