• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.264-264
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• 2012

As an environment-friendly alternative energy resource, ethanol may be used to obtain hydrogen, a clean energy source. Thus, studies on catalytic reactions involving ethanol have been studied to understand the underlying principles in the reaction mechanism using various oxide-supported catalysts. Among them, Au-based catalysts have shown a superior activity in producing hydrogen gas. In the present study, Au/$TiO_2$ catalysts were prepared by deposition-precipitation method to understand their catalytic activities toward ethanol and acetaldehyde with increasing gold loading, especially at the very low Au loading regime. A commercially available $TiO_2$ (Degussa P-25) was employed and the Au loading was varied to 0, 0.1, 0.5, and 1.0 wt% respectively. The catalysts showed characteristic x-ray diffraction (XRD) features at $2{\theta}=78.5^{\circ}$ that could be assigned to the presence of gold nanoparticles. Its reactivity measurements were performed under a constant flow of ethanol and acetaldehyde at a flow rate of ${\sim}0.6{\mu}mol/sec$ and the substrate temperature was slowly raised at a rate of 0.2 K/sec. We observed that the overall reactivity of the catalysts increased with increasing Au loading along with selectivity favoring dehydrogenation to product hydrogen gas. In addition, we disclosed various reaction channels involving competitive reaction paths such as dehydrogenation, dehydration, and condensation. In addition, subsequent reactions of acetaldehyde obtained from dehydrogenation of ethanol, were found to occur and produce butene, crotonaldehyde, furan, and benzene. Based on the results, we proposed overall reaction pathways of such reaction channels.

• Journal of Animal Science and Technology
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• v.54 no.3
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• pp.165-174
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• 2012

For horse breeders or managers, it is critical to understand the estrous cycle of mares. Breeding of mares cannot be successfully achieved throughout the whole year as mares breed seasonally. Mares are only able to breed when day length is more than 16 h, and this period is known as the breeding season. Their estrous cycle is approximately 21 days with 5-7 days of estrus and 14 to 15 days of a diestrus period. The estrous cycle of the mare is mainly controlled by gonadotropins, which control follicular development and ovulation. Mares exhibit unique ovulatory events which are not observed in other species. A LH surge occurs for several days, with levels of LH reaching their peak after ovulation. The LH level at the time of LH peak is lower than most other species. The unique anatomical structure of the ovaries of mares is known to limit the number of eggs ovulated. Several attempts have been made to develop chemical/hormonal agents which might be used to manipulate the timed ovulation of mares. Agents that have been tested include hCG, native GnRH, Deslorelin (Ovuplant, GnRH-agonist), Buserelin (GnRH analogue), equine pituitary extracts and equine chorionic gonadotropin (eCG or PMSG). However, the function, purity or stability of these agents is not reliable. Recombinant equine LH, an alternative agent for the timed ovulation, has been developed and tested for its biological activities, through the use of both in vitro and in vivo experiments. The reLH was suggested to be a reliable agent in inducing ovulation within 48 h after being administered through injection, when the size of dominant follicle is 35 mm in diameter.

• Environmental and Resource Economics Review
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• v.19 no.4
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• pp.897-914
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• 2010

The translog cost function of Korean Walleye pollock fishery is used to examine the impact of surface water temperature change led by global climate change. Catched of walleye pollock are very sensitive to water temperature and material cost. Elasticities of production to water temperature are -9%, significantly lower than we expected. There may be alternative explanations for the productivity decrease, including the possibility of overfishing and water pollution. However, the impact of climate change is obvious and inevitable. Therefore the government may encourage local fishermen to change from current cold water to warm water fisheries. Moreover continuos monitoring for the possibility of illegal activities at the East Sea. Finally, collaborated political efforts may be needed among the nations in the East Sea to conserve a Walleye Pollock fishery.

• Journal of the Korean association of regional geographers
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• v.9 no.3
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• pp.314-328
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• 2003

This study aims at exploring the restoration of local community based on apartment residential space through the questionnaire survey of residents and community movement organizers. Apartment residential space has a serious limit to the restoration of local community due to the physical feature of closing compartment. But, at the same time, it has many communal elements as well. The survey shows that residential community movements are developing beyond compensatory community movement, although it is yet to be an ideal type of local community in a nonnative sense. Generally, apartment women's associations, together with the representative commission of residents, play a key role in residential community movements. Particularly, community movement activities have a positive effect on improving the neighborhood relationship. Residents themselves think so as well. This study implies the value and possibility of apartment residential movement as an alternative strategy against contemporary urban problems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.8
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• pp.5176-5185
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• 2014

This study was conducted from 2010 to May 2012 to determine the volatile flavor compositions, biological activity and components of A. monanthum from different regions in Korea. The flavors of A. monanthum were extracted by SPME methods and it contained forty-two compounds that included mainly hydrocarbons and acids. The cancer cell growth inhibition activities of A. monanthum on the cancer cell (HaCaT, HepG2, HCT116, PC3) line were increased in a dose-dependent manner and the hexane fraction showed the highest antiproliferation effects. A. monanthum also showed the highest antioxidant activity. The results suggest that A. monanthum can be used as bioactive and functional materials.

• Journal of Pharmacopuncture
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• v.18 no.3
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• pp.32-41
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• 2015

Objectives: Condurango (Gonolobus condurango) extract is used by complementary and alternative medicine (CAM) practitioners as a traditional medicine, including homeopathy, mainly for the treatment of syphilis. Condurango bark extract is also known to reduce tumor volume, but the underlying molecular mechanisms still remain unclear. Methods: Using a cervical cancer cell line (HeLa) as our model, the molecular events behind condurango extract's (CE's) anticancer effect were investigated by using flow cytometry, immunoblotting and reverse transcriptase-polymerase chain reaction (RT-PCR). Other included cell types were prostate cancer cells (PC3), transformed liver cells (WRL-68), and peripheral blood mononuclear cells (PBMCs). Results: Condurango extract (CE) was found to be cytotoxic against target cells, and this was significantly deactivated in the presence of N-acetyl cysteine (NAC), a scavenger of reactive oxygen species (ROS), suggesting that its action could be mediated through ROS generation. CE caused an increase in the HeLa cell population containing deoxyribonucleic acid (DNA) damage at the G zero/Growth 1 (G0/G1) stage. Further, CE increased the tumor necrosis factor alpha ($TNF-{\alpha}$) and the fas receptor (FasR) levels both at the ribonucleic acid (RNA) and the protein levels, indicating that CE might have a cytotoxic mechanism of action. CE also triggered a sharp decrease in the expression of nuclear factor kappa-light-chain-enhancer of activated B cells ($NF-{\kappa}B$) both at the RNA and the protein levels, a possible route to attenuation of B-cell lymphoma 2 (Bcl-2), and caused an opening of the mitochondrial membrane's permeability transition (MPT) pores, thus enhancing caspase activities. Conclusion: Overall, our results suggest possible pathways for CE mediated cytotoxicity in model cancer cells.

• Explosives and Blasting
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• v.17 no.4
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• pp.8-17
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• 1999

Unfortunately leaks occur in heat exchangers periodically, usually at the tube to tubeplate joint. The usual method of repair is to plug off the defective area and isolate the tubes of concern from the circuit. If the leaks continua the thermal capacity of the units is progressively reduced and for this reason the alternative of using an internal bridging sleeve has been examined. This paper discusses the overall development activities that has been found necessary to bring this repair procedure to a successful conclusion for use on the nuclear steam generator. In this work we have investigated optimum explosives and explosive quality, explosive sleeving's thickness, the design of sheath stress relieving heat treatment pull-out load, hydraulic leakage, stress corrosion cracking properties. The results obtain are as follows : (1) The optimum explosives and explosive qualities are PETN and about 15~40 gr/ft of explosive sleeving in nuclear steam generator. (2) Explosive sleeving's thickness is 1.1~l.4mm, If groove of 0.35mm formed in sleeve outside existed, For the hydraulic leakage is go up, explosive sleeving of formed groove are applicate tube and turnplate. (3) If the stress relieving heat treatment are experiment in $750^\circ{C}$, $850^\circ{C}$, 15 minutes Pull-out strength of sleeving 1,500~2,300kg, hydraulic leakage is $250kg/cm^2$.

• Health Policy and Management
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• v.10 no.4
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• pp.1-19
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• 2000

We have witnessed several kinds of new discourses and practices in health and medicine since the 1970s, such as popular concerns with alternative or complementary medicine, inordinate attention to the promotion of 'healthy' living, rapid resurrection of traditional medicine and ecological management of health. Four structural and situational factors are discussed to underlie these new trends：(i) as 'crisis' in health care of the 1970s was translated into health care reform of the 1980s backed up by neo-liberal political philosophy, the state responsibility for nation's health is being transferred to the individual ；(ii) it resulted from the limits of biomedical paradigm in dealing with chronic diseases；(iii) medico-scientific knowledge of disease is transformed into the subjective discourses and technologies of health in postmodern society ； and (iv) it is deeply associated with the considerable increase in environmental risk perception of health and disease. There are some inherent countervailing forces in these new discourses and practices. First, while they derive from lifestyle-oriented behavioral change, medicalization of life and death is still consolidated in the new trends. Second, inasmuch as new tides are reliant upon science, they. are likely to be remote from techne that means not the practical application of theoretical knowing but a special form of practical knowing. Third, as new discourses and activities accomplished＇in the name of health＇increasingly occupy important strategies in forming the self-identity, they serve as moral apparatus which involves prescriptions about how we should live our lives and conduct our bodies, both individually and collectively. Therefore, two points are suggested to consider seriously whether these streams will succeed in improving the‘healthy’living of all the people. Instead of limiting tile perspective to medicine, healing and health care, a new matrix that interweave welfare, ecology and labor along with them is timely needed for enhancing the health for all. In addition, as the World Health Report fm strongly shows, inequality in health heavily depends upon socio-economic development of a society, and it is not the richest countries that have the best health status, but those that have the smallest income differences between rich and poor.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.3
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• pp.3-10
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• 2012

The investigation of valley networks and their volume provide important information about past water activities on Mars. As an alternative of conventional image processing methods, terrain filtering algorithm using pointcloud data is suggested in this study. First, the topography of pointcloud is inverted so that the valleys become positive features and the algorithm is then applied to distinguish the valleys from the surface. Ground DEM and object DEM are generated from both the valleys and the surface pointcloud then the volume of valleys is estimated by multiplying the height difference between the surface with valleys and the area of valleys based on grid cellsize. In the test of valleys adjacent to Tuscaloosa crater, the total volume of valleys was estimated to be $1.41{\times}10^{11}m^3$ with the difference of 12% and 16% compared with the infill volume of Tuscaloosa crater and BTH result respectively.

• Korean Journal of Construction Engineering and Management
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• v.6 no.1 s.23
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• pp.109-116
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• 2005

Recently, the design-build delivery system is being generalized in domestic construction project. The design-build system is becoming an increasingly preferable alternative to design-bid-build delivering method. In design-build project, however, a large construction company and design firm make up consortium as a design-build contractor rather din single company performs design and construction work. In this case, usually the construction companies take a leading role but due to their lack of managerial t31ow-how in the design-build system, they could miss the merits of this approach. Therefore, it is necessary to investigate throughly the function and information flows all over the design-build project. This research suggests a process model and database in the whole phase of design-build project. This process model and database system will also support to improve the consistency of functional process and minimize incoherent activities of the design-build projects.