• Journal of Powder Materials
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• v.3 no.4
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• pp.227-232
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• 1996

(i) The development of a metallurgical bond during the spray forming of clad products has offered the possibility of manufacturing large rolls, including those used in hot and cold strip mills. Small rolls are already being produced in Japan. (ii) Technical developments, including the use-of-multi-atomizers have resulted in the elimination of porosity from the internal bore of a sprayed tube. Bimetallic tubing can also be manufactured and the installation of a 4.5 ton tube plant in the USA should provide low operation costs. (iii) Spray forming offers a potentially low cost manufacturing route for superalloy ring/casing components in high strength superalloys. (iv) A large pilot plant has been built for the spray forming of ultra-clean superalloys for turbine disc applications. (v) Using twin-atomizing technology, special steel billets have been spray formed up to 400mm diameter with deposition yields in excess of 90%. (vi) Al/Si alloy extrusion billets with excellent dimensional tolerances are being manufactured for large scale automotive applications. Several new aluminum alloys have also been developed, including high strength, low density and low cocfficient of expansion materials. (vii) New copper alloys have been developed and pilot plants are in operation to produce these alloys once markets have become established.

• The Korean Journal of Pain
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• v.14 no.2
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• pp.142-149
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• 2001

Background: The expression of the proto-oncogene c-fos in spinal cord neurons following various noxious stimuli has been demonstrated in numerous studies. However, the pattern of expression of c-fos after incisional stimulus has not been evaluated. This study was designed to examine c-fos expression in an incisional pain model of rats. Methods: A 1 cm longitudinal incision was made through the skin, fascia and muscle of the plantar aspect of the hindpaw in enflurane-anesthetized rats. Withdrawal responses were measured using von Frey filaments at areas around the wound before surgery and for the next 48 hours. The expression of c-fos protein in the lumbar spinal cord was examined by immunohistochemistry. Results: After incision, c-fos was strongly expressed within laminae I, II, III, IV, V and VI ipsilateral to the incision. C-fos positive neurons were detected in the controlateral site, as well. Conclusions: These studies suggest that spinal c-fos protein may not be used as a specific marker for spinal nociceptive processing in an incisional pain model.

• Journal of Yeungnam Medical Science
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• v.20 no.2
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• pp.177-186
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• 2003

Background: Clinical and radiological results based on fracture types and associated injuries after the treatment of tibial plateau fracture were evaluated for analyzing prognostic factors. Materials and Methods: From June 1997 to June 2002, 50 cases were followed for at least 1 year. Mean age was 47.4 years, and mean follow period was 30.0 months. Fracture classification was performed by the Schatzker method. Clinical and radiological evaluation were performed by the Porter and Rasmussen method. Evaluation was based on degree of reduction and associated injuries, etc. Results: The most common cause of injury was traffic accident (37 cases, 74%), The common fracture types by Schatzker classification were type II (14 cases) and VI (12 cases). Methods of treatment were screw fixation (15 cases), plate and screw (21 cases), external fixator (5 cases), and conservative treatment (9 cases). The most common associated injuries were ipsilateral fibular fracture (18 cases) and MCL (medial collateral ligament) injury (8 cases). Conclusion: Acceptable results after treatment of tibial plateau fracture were obtained from the anatomical reduction group, non-associated injury group, the young age group, and the early ROM (range of motion) beginning group.

• Journal of environmental and Sanitary engineering
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• v.20 no.3 s.57
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• pp.27-35
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• 2005

The ion exchange resins have been synthesized from chlormethyl styrene - 1,4 -divinyl-benzene(DVB) with $1\%,\;4\%,\;and\;10\%$-crosslinking and macrocyclic ligand of cryptand type by copolymerization method and the adsorption characteristics of uranium(VI), calcium(II) and lutetium(III) metallic ions have been investigated in various experimental conditions. The synthesis of these resins was confirmed by content of chlorine, element analysis, and IR-spectrum. The effects of pH, time, dielectric constant of solvent and crosslink on adsorption of metallic ions were investigated. The uranium ion was showed fast adsorption on the resins above pH 3. The optimum equilibrium time for adsorption of metallic ions was about two hours. The adsorption selectivity determined in ethanol was in increasing order uranium $(UO_2^{2+})>calcium(Ca^{2+})>lutetium(Lu^{3+})$ ion. The adsorption was order of $1\%,\;4\%,\;and\;10\%$ crosslink resin and adsorption of resin decreased in proportion to order of dielectric constant of solvents.

• Journal of environmental and Sanitary engineering
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• v.19 no.1
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• pp.24-36
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• 2004

This study is to investigate the present condition of waste disposal establishment and to analysis problems which could be produced at location selection formalities of waste disposal establishment. It proposed building methods of waste disposal establishment to lead spontaneous participation of local resident according to case analysis of waste disposal establishment. There are research results; i) Opposition of inhabitants was the majority of reason at the business abandonment or delay of waste disposal establishment. Therefore agreement formation course with local inhabitants is most important position. ii) Many estimate have been needed for waste disposal establishment, but support estimate of government was 30-50% that is really low compare with other environmental establishment. So that it need to increase of government estimate. iii) Location collection is carried out based on law and final collected location must be executed without delay of relation business as soon as possible. iv) Standard of location collection has to divide into small, middle and large size and to apply with same rule according to divided location. v) It must be change public subscription before and location selection after and maintain continuance of information offer to local inhabitants and offered information. vi) after building of waste disposal establishment for solving distrust of waste disposal establishment. It must be planed and carried on useful support countermeasure to local inhabitants in actuality.

• Nuclear Engineering and Technology
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• v.52 no.7
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• pp.1557-1564
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• 2020

In this paper, 3D model-based interactive gamma ray shielding package (MIGSHIELD) is developed in virtual reality platform for windows operating system. In MIGSHIELD, the computational methodology is based on point kernel algorithm (PK), several key parameters of PK are obtained using new technique and new methods. MIGSHIELD has interactive capability with virtual world. The main features made in the MIGSHIELD are (i) handling of physical information from virtual world, (ii) handling of arbitrary shapes radioactive source, (iii) calculating the mean free path of gamma ray, (iv) providing interactive function between PK and virtual world, (v) making better use of PK for virtual simulation, (vi) plug and play. The developed package will be of immense use for calculations involving radiation dose assessment in nuclear safety and contributing to fast radiation simulation for virtual nuclear facilities.

• Journal of Environmental Science International
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• v.25 no.6
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• pp.817-827
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• 2016

The resistance in series model has been frequently used for determination of various filtration resistance to correctly understand the membrane fouling behaviour in MBR (membrane bio-reactor) for wastewater treatment. The cake layer resistance ($R_c$) which is commonly determined by calculation of flux dataset that are obtained empirically before and after removing the cake layer on membrane surface. However, the calculated Rc values are very dependent on the cleaning methods adapted for removal of cake layer. This study investigated how the various cleaning options affect $R_c$. Seven different cleaning methods were employed: i) ultrasonication (100 W, 10 min), ii) ultrasonication (200 W, 60 min), iii) ultrasonication (400 W, 120 min), iv) water rinsing in a shaker (100 rpm, 10 min), v) water rinsing in a shaker (300 rpm, 60 min), vi) water rinsing, vii) sponge scrubbing. For the hydrophilic PES membrane, the cake layer removal efficiencies ranged from 64% to 10%, indicating that the removal of cake layer was highly dependent on the cleaning options. For the hydrophobic PVDF membrane, the cake layer removal efficiencies ranged from 79% to 97%. Consequently, a standardized method for cake layer removal to determine cake resistance ($R_c$) is needed for correct interpretation of the fouling phenomena.

• The Bulletin of The Korean Astronomical Society
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• v.39 no.2
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• pp.111-111
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• 2014

Intensity interferometry, based on the Hanbury Brown--Twiss effect, is a simple and inexpensive method for optical interferometry at microarcsecond angular resolutions. Motivated by recent technical developments, we argue that the sensitivity of large modern intensity interferometers can be improved by factors up to approximately 25,000, corresponding to 11 photometric magnitudes, compared to the pioneering Narrabri Stellar Interferometer of the 1970s when resolving. Our approach, based on spectrally resolved light, permits the construction of large optical interferometers at the cost of (very) long-baseline radio interferometers. Realistic intensity interferometers are able to spatially resolve main-sequence O-type stars in the Magellanic Clouds. Multi-channel intensity interferometers can address a wide variety of science cases: (i) linear radii, effective temperatures, and luminosities of stars; (ii) mass-radius relationships of compact stellar remnants; (iii) stellar rotation; (iv) stellar convection and the interaction of stellar photospheres and magnetic fields; (v) the structure and evolution of multiple stars; (vi) direct measurements of interstellar distances; (vii) the physics of gas accretion onto supermassive black holes; and (viii) calibration of amplitude interferometers by providing a sample of calibrator stars.

• Journal of Acupuncture Research
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• v.23 no.1
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• pp.179-186
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• 2006

Background : Recently the demand was increasing on the data describing treatment rates and the outcome of Androgenetic Alopecia using Oriental Medicine. Thus this study was designed to observe androgenetic Alopecia treatment using Oriental Medicine including acupuncture and herb because there has been no such statistics. Objectives : Our purpose was determine whether oriental medicine treatment leads to clinical improvement in men with androgenetic alopecia. Methods : Eighty two Men, 17 to 53 years of age, with male pattern hair loss according to a modified Norwood/Hamilton classification scale(II to VI) were enrolled in this study. Patients were treated with multidisciplinary Korean oriental medicine treatment (herbal acupuncture, acupuncture, herb, chuna therapy) at twice a week for 6 months to 12 months. Efficacy was evaluated by patient and investigator assessment, and global photographic review. Results : Oriental medicine treatment improved scalp hair by all evaluation. Patient self assessment demonstrated that Oriental medicine treatment slowed hair loss, increased hair growth, and improvement appearance of hair. These improvements were corroborated by investigator assessments and assessments of photographs. Conclusion : Oriental medicine treatment has significant effects on the androgenetic alopecia. Longer follow up studies are needed to examine whether its effects last long enough for the patients with androgenetic alopecia.

• ETRI Journal
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• v.25 no.4
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• pp.258-265
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• 2003

In our study, we extracted the market, finance, and government factors determining R&D investment of individual firms in the IT industry in Korea. We collected the financial data of 515 individual firms belonging to IT and non-IT industries between 1980 and 1999 from the Korea Investors Service's database and investigated the empirical relationship between the factors using an ordinary regression model, a fixed effects model, and a random effects model. The main findings of our study are as follows: i) The Herfindahl Index variable representing the degree of market concentration is statistically insignificant in explaining R&D expenditures in the IT manufacturing industry. ii) Assets, which is used as a proxy variable for firm size, have a positive and statistically significant coefficient. These two results suggest that the Schumpeterian Hypothesis may be only partially applied to the IT manufacturing industry in Korea. iii) The dividend variable has a negative value and is statistically significant, indicating that a tendency of high dividends can restrict the internal cash flow for R&D investment. iv) The sales variable representing growth potential shows a positive coefficient. v) The subsidy as a proxy variable for governmental R&D promotion policies is positively correlated with R&D expenditure. This suggests that government policy has played a significant role in promoting R&D activities of IT firms in Korea since 1980. vi) Using a dummy variable, we verified that firms reduced their R&D investments to secure sufficient liquidity under the restructuring pressure during Korea's 1998 and 1999 economic crisis.