• Toxicological Research
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• v.15 no.1
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• pp.27-34
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• 1999

To study the nature of differentially manifested adaptive response of an organism according to the intensities of the stress, the immune effects of different levels of repeated hypoxia were investigated. Four experimental groups (NH : not -handled, 20% : handled, 15% or 10% : exposed to 15% or 10% $\textrm{O}_2$ 씨오투 with balanced nitrogen, respectively) of mice were exposed to different levels of hypoxia for 60 min/day, 5days/week in a repeated and intermittent manner. After 8 weeks' exposure to hypoxia environment, mice were subjected to immune function measurements, A decreased proportion of CD3+ CD8 phenotype cells in the study of splenocyte subsets was observed in the 10% group. Ovalbumin-stimulated IgG2a production was increased in the 15% group, while no changes were noted in the IgGl and IgM production. No significant changes of the antigen-stimulated splenocyte proliferation and the natural killer cell cytotoxicity were found. These results show that the stress effects on the immune systems can be varied according to the strength of the stress and that a mild level of repeated hypoxic stress can enhance the immune function of mice in this experimental model.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.33 no.3
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• pp.202-208
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• 1997

The component materials threatened by cavitation include ship propellers as well as turbine runners, pump impellers, pipe lines and radiators. Today it is known that cavitation damage takes place on many other components including on the coding water side of the cylinder liners of diesel engines. Cavitation erosion - corrosion implies damage to materials due to the shock pressure or shock wave that results when bubbles form and collapse at a metal surface within a liquid. To suppress cavitation erosion as well as cavitation erosion - corrosion to hydraulic equipment, innovations such as the improvement in the geometric design of the equipment or the selection of suitably resistant construction materials are necessary. In this study, we investigated that the cavitation erosion - corrosion damage under vibratory cavitation can be reduced by adding of side now velocity to the cavitation bubble group in order to eliminate bubbles formed in sea water environment.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.7
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• pp.713-720
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• 2011

This study investigated the effect of cold acclimatization training on body composition including weight, fat mass, and muscle mass with 10 subjects (5 males and 5 females). During the 3-week acclimatization training program, they visited an artificial climate chamber ($15^{\circ}C$) 15 times and were exposed to cold environment with light clothing for 2 hours. Body composition was measured before and after cold training using bioelectric impedance analysis that was later compared by a paired t-test. In the process of thermoregulation, muscle contraction was accompanied by increased substrate metabolism for rising heat production. After cold training, the muscle mass increased and fat mass decreased significantly (p<.1, p<.05), subsequently the body composition changed. It was found that cold acclimatization training could be used as a treatment for obesity. It was suggested that further investigation on the long term effects of mild cold exposure using clothing and its potential applicability as an obesity treatment.

• Animal cells and systems
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• v.16 no.6
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• pp.462-468
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• 2012

Urodeles including newt and salamander have remarkable regenerative capacity during the postembryonic life span. Some of the unique features are the formation of the well-developed wound epidermis and the active dedifferentiation process in the early phase of regeneration. These are regarded as key events for the successful regeneration since no further regenerative activity is possible without them. In this study, we investigated the role of retinoic acid (RA) in salamander limb regeneration by blocking RA synthesis using disulfiram, an inhibitor of aldehyde dehydrogenase that oxidizes retinal to RA. Disulfiram treatment resulted in delaying the limb regeneration processes via inhibition of wound epidermis formation and dedifferentiation process. When RA was administered after disulfiram treatment, the inhibitory effect of disulfiram was rescued. In addition, disulfiram treatment after the dedifferentiation stage resulted in the mild retardation of limb regeneration, suggesting that RA might also be involved in the blastema outgrowth. Furthermore, salamander MMP-9 gene expression was also inhibited by disulfiram treatment. Collectively, our findings indicate that endogenous RA may play an important role(s) in the early phase of limb regeneration by regulating the expression of molecules responsible for the modification of intracellular and extracellular environment during salamander limb regeneration.

• Korean Journal of Social Welfare
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• v.49
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• pp.319-342
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• 2002

The nuclear family is no longer the typical Korean Family. In recent years, stepfamilies have been of the most rapidly growing family forms in Korea. Census Bureau data show that 5.9% of marriage were in 1980, 8.0% in 1990, 10.3% in 1995, 18.0% in 2000. Especially it is remarkable that women's remarriage have been increased. In spite of the fact, the stepfamily is not an urgent issue of social welfare in Korea. The stepfamily is more vulnerable than the first-marriage family in many reasons such as vague family rules, boundary ambiguity, and stepparent role ambiguity, which provides rationale for social welfare services. This study categorizes determinants of psychological distress in remarried mothers into individual, family, and environment level and tries to prove the relationships between psychological distress and determinants. Also, it explores the degree of psychological distress in remarried mothers using Zung's Self-Rating Depression Scale. The respondents of survey research are 62 cases. The result shows relatively severe level of depression among the subjects. 46.8% of them are clinically diagnosed as mild, moderate, severe depression. Our findings suggest that the variables of marriage satisfaction, ex-wife's remarriage, role strains, marriage experience, and income are significantly associated with the level of psychological distress in remarried mothers. The most powerful predictor of psychological distress is the variable of marriage satisfaction. According to the result, it is desperately needed to pay attention to social welfare services or programs for stepfamilies.

• Corrosion Science and Technology
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• v.3 no.5
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• pp.194-197
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• 2004

The corrosion resistance of several kind of ME (Metal Evaporated) tape has been investigated both in mild sulfuric acid solution and NaCl solution by electrochemical impedance spectroscopy. It was found that the degradation of ME tapes was accelerated with increasing the concentration of sulfuric acid. There was no significant change in corrosion resistance when the concentration of NaCl was under 3.5 wt%. However, the impedance value decreased when the concentration of NaCl was up to 10 wt%. The degradation of backside of ME tapes was also investigated by AC impedance measurements. The results showed that the impedance behavior of backside plastic film changed with the concentration of sulfuric acid even at the beginning of immersion, implying the changing of the permeability for the backside of ME tapes. It was also found that the corrosion resistance of DVC (Digital Video Cassette) ME tape was better that that of Hi-8mm ME tapes in sulfuric acid solutions. Also, the backside of DVC ME tape showed better water resistance than that of Hi8 ME tapes.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.11a
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• pp.35-35
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• 2011

Phase change material(PCM) has thermal energy storage and been attracted attention. Latent heat of the organic PCM can keep maintaining temperature when the change of outside energy conditions influence to PCM. Thus, many researchers have interested to thermal energy storage ability and investigated to applications such as thermal storage of solar energy, bioclimatic building, icebank, medical application, clothing industry and so on. Among the many applications, investigation of the PCM in clothing industry is also important because the people has interest functional factor called health-care in the clothing. In addition, PCM can give them mild environment condition such suitable temperature control or humidity. To fabrics, the PCM has various methods such as microcapsule, padding and modified cross-section formation(Sheath/core). Sheath core PCM fabric has a better benefit of durability than other method. However, PCM sheath/core spinning is difficult. In addition, dyeing property is important to use clothing industry due to visual images. In this study, we investigated dyeing properties of Nylon/PCM sheath/core fabrics. Especially, we observed the relation between dyeing property and PCM including ratio. Various temperature and pH conditions were also studied to optimize dyeing properties as acid dye.

• KIEAE Journal
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• v.7 no.5
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• pp.81-86
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• 2007

The research analyzes the arrangement of boiler and hot water header, the method of radiator pipe setting, hot water supply control, hourly heating situation of each room for underfloor radiant heating systems in Korea and suggests an alternative to improve to efficient heating method. One of the best options for install position of hot water distributor is under kitchen sink which is center point of all rooms, according to previous research of the energy saving strategies. When the radiator pipes are arranged to each individual room instead of bedrooms through livingroom and kitchen, it has energy saving effects. For rooms without occupancy according to a time period, hot water supply method should be intermittent heating rather than continuous heating. For this intermittent heating method, individual control of hot water supply is more practical, and it can lead to massive energy savings. The intermittent heating system has time-lag, so it is more effective in energy saving with mild and comfort condition if the spaces are preheated by automatic control equipment prior to required time.

• Korean Journal of Veterinary Research
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• v.4 no.1
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• pp.7-14
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• 1964

Seven cases of canine babesiasis were observed by clinically, hematologically and immunologically in the Kyungbook and Pusan area from May 1961 to October 1963. And a survey was conducted on the rising pups for their babesia, infection in the broken out districts of the disease. The results obtained were as follows: 1. Severe cases of canine babesiasis due to the same agent have been encountered in various breed, of dogs in widely separated location in the Kyungpook and Pusan area. 2. The principal symptoms oserved in infected dogs were severe anemia, weakness, inappetence, moderate fever or subnormal body temperature, increased respiration and pulse, palpitation, icterus, hemogrobinuria and redish yellow defecation. 3. Of hematological findings, decrease in erythrocytes count, hemoglobin content was evident and severe anemic changes occured which were associated with macrocytic anisocytosis. The differential leucocytes counts showed a tendency to increased monocytes and decreased monocytes and decreased basophil. 4. The principal anatomic chabges observed in two cases of infected dogs were severe anemic and icteric changes, markedly enlarged spleen, and enlarged liver with distended gall bladder. 5. Haemaphysalis bispinosa was suspected as being the principal vector of the infection. 6. It was suspected that chronic canine babesiasis would prevailed widely in Kyungpook and Pusan area, and that dogs are raised in such infected environment usually suffer only from the mild, chronic form, which may be practically symptomless, while imported dogs usually suffer from the acute form of the disease.

• Nuclear Engineering and Technology
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• v.53 no.6
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• pp.1756-1768
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• 2021

The containment filtered venting system (CFVS) filters the atmosphere of the containment building and discharges a part of it to the outside environment to prevent containment overpressure during severe accidents. The Korean CFVS has a tank that filters fission products from the containment atmosphere by pool scrubbing, which is the primary decontamination process; however, prediction of its performance has been done based on researches conducted under mild conditions than those of severe accidents. Bubble behavior in a pool is a key parameter of pool scrubbing. Therefore, the bubble behavior in the pool was analyzed under various injection flow rates observed at the venturi nozzles used in the Korean CFVS using a wire-mesh sensor. Based on the experimental results, void fraction model was modified using the existing correlation, and a new bubble size prediction model was developed. The modified void fraction model agreed well with the obtained experimental data. However, the newly developed bubble size prediction model showed different results to those established in previous studies because the venturi nozzle diameter considered in this study was larger than those in previous studies. Therefore, this is the first model that reflects actual design of a venturi scrubbing nozzle.