• Journal of the Korean Magnetics Society
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• v.14 no.3
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• pp.99-104
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• 2004

We have studied to understand the barrier and interface qualities and structural changes through measuring temperature dependent spin-polarization as functions of plasma oxidation time and annealing time. Magnetic tunnel junctions consisting of SiO2$_2$/Ta 5/CoFe 17/IrMn 7.5/CoFe 5/Al 1.6-Ox/CoFe 5/Ta 5 (numbers in nm) were deposited and annealed when necessary. A 30 s,40 s oxidized sample showed the lowest spin-polarization values. It is presumed that tunneling electrons were depolarized and scattered by residual paramagnetic Al due to under-oxidation. On the contrary, a 60s, 70 s oxidized sample might have experienced over-oxidation, where partially oxidized magnetic dead layer was formed on top of the bottom CoFe electrode. The magnetic dead layer is known to increase the probability of spin-flip scattering. Therefore it showed a higher temperature dependence than that of the optimum sample (50 s oxidation). temperature dependence of 450 K annealed samples was improved when the as-deposited one compared. But the sample underwent 475 K and 500 K annealing exhibits inferior temperature dependence of spin-polarization, indicating that the over-annealed sample became microstucturally degraded.

• Korean Journal of Acupuncture
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• v.30 no.1
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• pp.64-72
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• 2013

Objectives : The aim of this study was to investigate whether warm-needling is more effective than acupuncture in relieving the pain and improving the symptoms of knee osteoarthritis(OA). Methods : 76 volunteers with knee OA participated in the study. The subjects were randomly assigned to one of two groups. One group received warm-needling(n=38), while the other group received acupuncture(n=38). Sixteen sessions of warm-needling or acupuncture were conducted on the pain region of each problematic knee over a period of 8 weeks. The Western Ontario and McMaster Universities Osteoarthritis Index(WOMAC) scores, physical health score based on the 36-Item Short-Form Health Survey(SF-36) and the Global Assessment(PGA) was measured. Results : Compared to the acupuncture group, the warm-needling group showed a significant decrease in pain, function, and total WOMAC scores according to the Mann-Whitney U-test. The PGA scores of the warm-needling group also showed a significant improvement compared to the acupuncture group. Conclusions : Warm-needling showed a greater pain relief effect on knee OA compared to the acupuncture group. These findings suggest that warm-needling may be a promising alternative therapy for treating knee OA.

• Journal of Life Science
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• v.21 no.4
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• pp.568-575
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• 2011

TMR feed developed by adding mugwort originating from Jeju Island,was fed to Hanwoo to investigate the effects of feeding mugwort on nutritional composition, as well as the feasibility of producing Hanwoo beef with high quality and functionality. The samples for the experiment consisted of Hanwoo fed fattening cattle TMR feed without mugwort (control), and Hanwoo fed fattening cattle TMR feed with added mugwort (treatment). Feeding mugwort did not lead to a significant difference in the moisture, crude protein, crude fat, crude ash, calorie, cholesterol, and collagen contents. There was no significant difference between the control and treatment groups in mineral components. The control and treatment groups had total mineral amounts of 3,559.20 and 3,998.01 ppm, respectively. The total amount of structural amino acids did not show any significant difference between the control (14.56%) and treatment groups (13.90%). The total amount of free amino acids did not show any significant difference between the control (763.044 ppm) and treatment groups (720.885 ppm). The composition of saturated fatty acids was 42.956% for the control and 40.918% for the treatment group. Further, the composition of unsaturated fatty acids was 57.044% for the control and 59.082% for the treatment group. Myristic acid, myristoleic acid, pentadecenoic acid, palmitic acid, and ${\gamma}$-linolenic acid were increased by feeding mugwort. Arachidic acid was contained the most among the fatty acid of Hanwoo fed feed without mugwort (p<0.05).

• Journal of Life Science
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• v.19 no.11
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• pp.1672-1678
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• 2009

The purified antifungal substances produced by Bacillus amyloliquefaciens IUB158-03 was positive to ninhydrin but negative to aniline, suggesting that the antifungal substance could be a peptide. FAB-MS, UV adsorption spectrum, and amino acid composition analysis revealed that the molecular weight of the antifungal substance was 1042 and that maximal adsorption was at 220 nm and 277 nm. The antifungal substance was composed of $Asn_3$, $Gln_2$, $Ser_1$, $Gly_1$, and $Tyr_1$. The composition and structural characteristics of antifungal substance were analysed by $^1H$-NMR spectrum, $^1H$-COSY, HMQC, which revealed that the compound belongs to the iturin A family. Temperature and pH had little effect on the stability of the antifungal substance in the ranges of $-70{\sim}121^{\circ}C$ and pH 6.0~10.0, respectively. It showed strong antibiotic activity against fungi. An in vitro cytotoxicity test using NIH3T3 cell showed that the antifungal substance does not have cytotoxicity. The number of circulating leukocytes and the hematobiological analysis of the mice administered with the antifungal substances was similar to those of the control group, indicating no cytotoxicity in vivo. Therefore, the antifungal substances extracted from culture broth of Bacillus amyloliquefaciens IUB158-03 have future potential as biocontrol agents against plant diseases caused by fungi.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.183-184
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• 2013

Two main MBE growth techniques have been used: plasma-assisted MBE (PA-MBE), which utilizes a rf plasma to supply active nitrogen, and ammonia MBE, in which nitrogen is supplied by pyrolysis of NH3 on the sample surface during growth. PA-MBE is typically performed under metal-rich growth conditions, which results in the formation of gallium droplets on the sample surface and a narrow range of conditions for optimal growth. In contrast, high-quality GaN films can be grown by ammonia MBE under an excess nitrogen flux, which in principle should result in improved device uniformity due to the elimination of droplets and wider range of stable growth conditions. A drawback of ammonia MBE, on the other hand, is a serious memory effect of NH3 condensed on the cryo-panels and the vicinity of heaters, which ruins the control of critical growth stages, i.e. the native oxide desorption and the surface reconstruction, and the accurate control of V/III ratio, especially in the initial stage of seed layer growth. In this paper, we demonstrate that the reliable and reproducible growth of GaN on Si (110) substrates is successfully achieved by combining two MBE growth technologies using rf plasma and ammonia and setting a proper growth protocol. Samples were grown in a MBE system equipped with both a nitrogen rf plasma source (SVT) and an ammonia source. The ammonia gas purity was ＞99.9999% and further purified by using a getter filter. The custom-made injector designed to focus the ammonia flux onto the substrate was used for the gas delivery, while aluminum and gallium were provided via conventional effusion cells. The growth sequence to minimize the residual ammonia and subsequent memory effects is the following: (1) Native oxides are desorbed at $750^{\circ}C$ (Fig. (a) for [$1^-10$] and [001] azimuth) (2) 40 nm thick AlN is first grown using nitrogen rf plasma source at $900^{\circ}C$ nder the optimized condition to maintain the layer by layer growth of AlN buffer layer and slightly Al-rich condition. (Fig. (b)) (3) After switching to ammonia source, GaN growth is initiated with different V/III ratio and temperature conditions. A streaky RHEED pattern with an appearance of a weak ($2{\times}2$) reconstruction characteristic of Ga-polarity is observed all along the growth of subsequent GaN layer under optimized conditions. (Fig. (c)) The structural properties as well as dislocation densities as a function of growth conditions have been investigated using symmetrical and asymmetrical x-ray rocking curves. The electrical characteristics as a function of buffer and GaN layer growth conditions as well as the growth sequence will be also discussed. Figure: (a) RHEED pattern after oxide desorption (b) after 40 nm thick AlN growth using nitrogen rf plasma source and (c) after 600 nm thick GaN growth using ammonia source for (upper) [110] and (lower) [001] azimuth.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.8 no.1
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• pp.41-48
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• 2010

Uranium deposits from an electrorefining process contain about 30% salt. In order to recover pure uranium and transform it into an ingot, the salts have to be removed from the uranium deposits. Major process variables for the salt distillation process of the uranium deposits are hold temperature and vacuum pressure. Effects of the variables on the salt removal efficiency were studied in the previous study[1]. By applying the Hertz-Langmuir relation to the salt evaporation of the uranium deposits, the evaporation coefficients were obtained at the various conditions. The operational conditions for achieving above 99% salt removal were deduced. The salt distilled uranium deposits tend to form the eutectic melt with iron, nickel, chromium for structural material of salt evaporator. In this study, we investigated the hold temperature limitation in order to prevent the formation of the eutetic melt between urnaium and other metals. The reactions between the uranium metal and stainless steel were tested at various conditions. And for enhancing the evaporation rate of the salt and the efficient recovery of the distilled salt, the thermal analysis of the salt distiller was conducted by using commercial CFX software. From the thermal analysis, the effect of Ar gas flow on the evaporation of the salt was studied.

• The Korean Journal of Pesticide Science
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• v.11 no.2
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• pp.72-81
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• 2007

Quantitative structure-activity relationships (QSARs) on the pre-emergency herbicidal activity and reactivity of a series of new O,O-dialkyl-1-phenoxyacetoxy-1-methylphosphonates (S) analogues against seed of cucumber (Cucumus Sativa) were discussed quantitatively using 2D-QSAR and HQSAR methods. The statistical values of HQSAR model were better than that of 2D-QSAR model. From the frontier molecular orbital (FMO) interaction between substrate molecule (S) and $BH^+$ ion (I) in PDH enzyme, the electrophilic reaction was superior in reactivity. From the effect of substituents, $R_2$-groups in substrate molecule (S) contributed to electrophilic reaction with carbonyl oxygen atom while X, Y-groups contributed to nucleophilic reaction with carbonyl carbon atom. And the influence of X,Y-groups was more effective than that of $R_2$-groups. As a results of 2D-QSAR model (I & II) and atomic contribution maps with HQSAR model, the more length of X, Y-groups is longer, the more herbicidal activity tends to increased. And also, the optimal ${\epsilon}LUMO$ energy, $({\epsilon}LUMO)_{opt.}$=-0.479 (e.v.) of substrate molecule is important factor in determining the herbicidal activity. It is predicted that the herbicidal activity proceeds through a nucleophilic reaction. From the analytical results of 2D-QSAR and HQSAR model, it is suggested that the structural distinctions and descriptors that contribute to herbicidal activities will be able to applied new herbicide design.

• The Journal of the Korea Contents Association
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• v.13 no.7
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• pp.350-360
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• 2013

The satisfaction of customers, who are in a servicescape, will be subject to many environment stimulations. In particularly, in the hospitality industry such as restaurants service experience for customer is very important. Thus, not only the stylistic elements but also the social and socially symbolic elements. So this paper expands Bitner's servicescape framework by conceptualizing the existence of a expanded servicescape. The expanded servicescape has three important dimensions, which is the physical, the social and the socially symbolic. Structural modeling largely supports the hypothesized framework and the results about the relationship between expanded servicescape factors, relationship quality(satisfaction, trust, commitment) and repurchase are summarized as follows. And this study utilizes a questionnaire survey to gather data regarding consumers' perceptions by using expanded servicescape. First, the analysis proved that except comfort the physical dimensions which including comfort, convenience, aesthetics caused a positive impact on customer satisfaction. Second, social dimensions which including appearance, etiquette and professionalism caused a positive impact on customer trust. Third, except community symbolic dimensions which including nostalgia, connection to culture caused a positive impact on customer commitment. Forth, it proved that expected relationship quality(customer satisfaction, trust, commitment) caused a positive impact on repurchase behavior.

• Journal of Distribution Science
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• v.12 no.6
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• pp.31-39
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• 2014

Purpose - Environmental issues, climatic changes, and greenhouse gases are problems to be solved at a global level. With an increased emphasis on the environmental and social responsibility of the management of companies, the manner in which companies approach quality-oriented culture and their individual sustainability management are being discussed as truly important issues to help them secure their competitiveness and growth strategies. This study proposes strategic directions to help manufacturers not only in expanding their competitive quality-oriented company culture but also in strengthening their sustainability management abilities. This study conducts a literature review and empirical research to examine how significantly the variables of a quality-oriented company culture, customer-centered management, and process-centered and supply chain management-centered cooperation affect sustainability management performance in relation to economic profitability, environmental integrity, and social responsibility. Research design, data, and methodology - To verify research models and hypotheses, the study examined 170 companies using a questionnaire survey conducted over six weeks, and involved the performance of data analysis on 146 samples. Questionnaire responses were calibrated based on a Likert scale. The study used the Smart PLS 2.0 program designed for PLS (partial least squares), an analysis instrument of SEM (structural equation modeling). The study then verified empirical research hypotheses working on reliability analysis, validity analysis, factorial analysis, and path analysis. Results - Among the nine hypotheses, four are accepted and the rest are rejected. A quality-oriented company culture focusing on customer-centered management significantly influenced the maintainability management performance of environmental integrity and social responsibility, while economic profitability was dismissed. A process-focused quality-oriented company culture was significantly concerned with economic profitability but not with environmental integrity or social responsibility. A supply-chain cooperative company culture had a significant effect on economic profitability but not on environmental integrity or social responsibility. Conclusion - This study proposes strategic directions to help manufacturers expand their competitive quality-oriented company culture as well as strengthen abilities with sustainability management. It conducts a literature review and empirical research to examine how significantly the variables of quality-oriented company culture, customer-centered management, and process-centered and supply chain management-centered cooperation affect sustainability management performance in relation to economic profitability, environmental integrity, and social responsibility. There are two main conclusions. First, companies should consider the need for social responsibility management and environmental transparent management-focused maintainability management as avenues to create new markets and business, thereby helping the companies secure a reputation for having a customer and process-centered quality-oriented company culture by creating shared values between supply chains and enabling win-win situations through cooperation. Second, we are marching towards a creative win-win era from a society of conflicts and ruptures. Companies should understand that social responsibility management and supply chain management (SCM)-focused cooperation are the foundations of sustainable development, as they try to improve their culture while pursuing both win-win relationships with interested parties and equity in various conflictive relations.

• Journal of Distribution Science
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• v.11 no.1
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• pp.25-34
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• 2013

Purpose - This study examines the adverse press coverage that has increased in proportion to the remarkable growth of various kinds of franchise businesses in the food service industry. Today, the trust of franchisees in relation to their franchisor, and the maintenance of good relations between the two, has become a significant social issue. This study investigates relationship satisfaction and the long-term commitment between the franchisor and franchisee. Research design, data, methodology - We used a path analysis to investigate the relationship between justice and trust, trust and relationship satisfaction, justice and relationship satisfaction, trust and long-term commitment, and relationship satisfaction and long-term commitment. Structural Equation Modeling and a Sobel test were used to investigate the mediating effects of trust and relationship satisfaction. Data were collected from 237 Food Franchisees in Seoul and Gyeonggi Province in order to test the theoretical model and its hypotheses. Two research methodologies are generally used in the distribution management field. For this study, an empirical method was used. Results - A causal analysis was carried out to test if the research model has a sufficient fit index (for instance, χ² = 46.694, df = 10, p = .000, GFI = 0.946, AGFI = 0.850, RMR = 0.034, NFI = 0.966, CFI = 0.973), and the results showed that the model was sufficient, thus demonstrating the suitability of the research model. Each hypothesis had a positive influence, both on long-term commitment and relationship satisfaction. Justice with the franchisor had a positive influence on trust. Relation satisfaction cognized by franchisees was found to positively influence long-term commitment. The franchisee perception of justice in relation to the franchisor had no significant influence on long-term commitment. The study investigated the hypothesis that trust could mediate justice and long-term commitment, and that relationship satisfaction could also mediate long-term commitment Both trust and relationship satisfaction were found to be important for long-term commitment. Specifically, trust sub-factors and justice sub-factors influenced long-term commitment. Identification-based and knowledge-based trust were more important than calculus-based trust. Distributive justice was deemed more important than procedural justice; distributive justice should thus be strengthened. Conclusions - Both franchisor and franchisee were independent businesses. Evidently however, the franchisor could not ensure profit without long-term commitment from the franchisee. As for the success of the franchise business, the franchisor should carry out appropriate strategies leading to a satisfactory relationship. For example, transparency makes it possible to maintain and enhance trust and to improve relationship satisfaction. Just relations between franchisor and franchisee should make it possible to maintain and enhance the franchisee's trust. The franchisor should provide a variety of information with respect to the franchisee's business success. Finally, in order to improve the franchisee's long-term commitment, the franchisor should ensure a just approach with trust and relationship satisfaction among their strategies.