• Journal of the Korean Electrochemical Society
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• v.3 no.1
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• pp.49-56
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• 2000

In the present we.k, temperature dependence of oxygen diffusivity in the polyvinyl chloride (PVC) film $D_f$ formed on gold electrode was investigated using steady-state rotating disk electrode (RDE) technique and modulated electrohydrodynamic (EHD) impedance technique. Both the diffusion rate defined as the ratio of oxygen diffusivity in the PVC film to the film thickness $D_f/\delta_f$ and the time constant $\delta_f^2/D_f$ for oxygen diffusion through the PVC film were obtained from plot of the limiting current versus disk rotation speed and from filing the EHD impedance spectra experimentally measured to those theoretically calculated on the basis of the diffusion equation for mass transport through the non-conductive and porous film, respectively. By combining measured $D_f/\delta_f$ with $\delta_f^2/D_f$, we determined $\delta_f\;and\;D_f$ at room temperature separately. As temperature increased, it appeared that the $D_f$ value measured for the PVC film-covered gold RDE was enhanced more rapidly than that $D_s$ value in the solution measured for the PVC film-free gold RDE. This means that the pores glowing with increasing temperature act as effective diffusion paths within the film. The present in-situ steady-state and modulated EHD measurements prove to be effective for determining $\delta_f\;and\;D_f$, separately and at the same time the porosity of the PVC film at temperatures below glass temperature $T_g$ of the film.

• Korean Journal of Soil Science and Fertilizer
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• v.26 no.1
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• pp.49-56
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• 1993

The net flux of global green house gases such as carbon dioxide($CO_2$), methane($CH_4$), and nitrous oxide($N_2O$) emitted from the rotation of paddy-upland soil during growing sesaon under different cropping system was determined. The results obtained were summarized as follows : 1. The net flux of $CO_2$ during the growing season was the highest from continuous cultivation of rice but the lowest from rotation cultivation of rice-soybean. Under the different cropping system the highst emission was from soil of continuous cultivation of rice, but the lowest from converted system. 2. The net emission of methane was the highest from the sold of continuous cultivation of rice, but the flux was remarkably decreased by differing the cropping system. 3. $N_2O$ was emitted greatly from the every two year rotation of potato-chinese cabbage and the next rank was from continuous cultivation of rice, but was decreased notably from rotation cultivation of rice-soybean and potato-chinese cabbage under rotation of paddy-upland cropping system. 4. The ratio of oxygen and carbon dioxide in the soil air was much different with glowing season, the ratio was varied with 4~10 percents for oxygen and 1~22 percents for carbon dioxide. The ratio of carbon dioxide was dozens or hundreds times to that of air, and the variation was very high also. 5. The emission of global green house gases such as carbon dioxide, methane and nitrous oxide was affected by the moisture, temperature and nutrients of soils and the growth period of crops.

• The Journal of the Petrological Society of Korea
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• v.11 no.2
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• pp.74-89
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• 2002

Rock units, relating with the Guamsan caldera, are composed of Guamsan Tuff and rhyolitic intrusions. The Guamsan Tuff consists almost entirely of ash-flow tuffs with some volcanic breccias and fallout tuffs. The volcanic breccia comprises block and ash-flow breccias of near-vent facies and caldera-collapse breccia near the ring fracture. The lower ash-flow tuffs are of an expanded pyroclastic flow phase from the pyroclastic flow-forming eruption with an ash-cloud fall phase of the fallout tuffs on the flow units, but the upper ones are of a non-expanded ash-flow phase from the boiling-over eruption. The rhyolitic intrusions are divided into intracaldera intrusions and ring dikes that are subdivided into inner, intermediate and outer dikes. We compile the volcanic processes along a single cycle of cadela development from the eruptive phases in the Guamsan area. The explosive eruptions began with block and ash-flow phases from collapse of glowing lava dome caused by Pelean eruption, progressed through expanded pyroclastic flow phases and ash-cloud fallout phases during high column collapse of pyroclastic flow-forming eruption from a single central vent. This was followed by non-expanded ash-flow phases due to boiling-over eruption from multiple ring fissure vents. The caldera collapse induced the translation into ring-fissure vents from a single central vent in the earlier eruption. After the boiling-over eruption, there followed an effusive phase in which rhyolitic magma was injected and erupted to be progressively emplaced as small plugs/dikes and ring dikes with many lava domes on the surface. Finally rhyodacitic magma was on emplaced as a series of dikes along the junction of both outer and intermediate dikes on the southwestern side of the caldela.

• Nuclear Medicine and Molecular Imaging
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• v.40 no.3
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• pp.155-162
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• 2006

Purpose: Diabetes mellitus (DM) is a critical disease with higher rates of cardiovascular morbidity and mortality due to myocardial ischemia and infarction. There is glowing interest in how to determine high-risk patients who are candidates for screening testing. This study was performed to evaluate the incidence of coronary artery disease (CAD) in diabetic patients detected by Tc-99m MIBI myocardial perfusion SPECT (MPS) and to assess risk factors of CAD and cardiac hard events. Subjects and Methods: 203 diabetic patients (64 male, mean age $64.1{\pm}9.0$ years) who underwent MPS were included between Jan 2000 and July 2004. Cardiac death and nonfatal myocardial infarction (MI) were considered as hard events, and coronary angioplasty and bypass surgery >60 days after testing were considered as soft events. The mean follow-up period was $36{\pm}18$ months. Patients underwent exercise (n=6) or adenosine stress (n=197) myocardial perfusion SPECT. Results: Perfusion defects on MPS were detected in 28.6% (58/203) of the patients. There was no cardiac death but 11 hard events were observed. The annual cardiac hard event rate was 1.1%. In univariate analysis of clinical factors, typical anginal pain, peripheral vascular disease, peripheral polyneuropathy, and resting ECG abnormality were significantly associated with the ocurrence of hard events. Anginal pain, peripheral vascular disease, and resting ECG abnormality remained independent predictors of nonfatal MIs with multivariate analysis. Abnormal SPECT results were significantly associated with high prevalence of hard events but not independent predictors on uni- and multivariate analyses. Conclusion: Patients who were male, had longer diabetes duration (especially over 20 years), peripheral vascular disease, peripheral polyneuropathy, or resting ECG abnormality had higher incidence of CAD. Among clinical factors in diabetic patients, typical angina, peripheral vascular disease, peripheral polyneuropathy, and resting ECG abnormality were strong predictors of hard events.

• Korean Journal of Construction Engineering and Management
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• v.5 no.5 s.21
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• pp.183-192
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• 2004

Even in Korea the number of steel structure buildings that allow internal space and easy change of their layouts in accordance with the purpose of buildings and box-type steel bridges constructed with thick plates with thickness in a rage just from a few $\beta$AE to \$100\beta$AE is increasing these days and therefore, domestic fabrication and processing technology of members for steel structures is being improved at a pace faster than in the past to meet the growing requirements of consumers for high reliability on quality control on the related steel structures. However, most domestic fabricators os steel structures who are turning out their steel products in accordance with the designs prepared by engineering companies in their respective works for the sake of cost cut more than anything else, hesitating to introduce any advanced new technology into themselves. In the case of the steel structure design application for small and mid-size buildings in particular, it is quite meaningful not only for those who are involved in steel structure business, but also for the people working at construction work fields to review the result of the study on the connections of steel structure members deigned to obtain superb quality of steel structures within short period for steel fabrication and erection at fields in economical ways, as there is a glowing tendency seeking standardization of connection of steel structure members as well as whole structure together with the development on design of construction system of buildings including their exterior and interior decoration materials, manufacture of the related members and fabrication technique structure. This paper has been prepared with the aim to review the peculiar characteristics of buildings constructed with the main frames of steel structures and actual cases of the change made ing the connections between steel structure columns and between columns and girder members in order to reduce the work period necessary for fabrication and erection of steel structures at the maximum as well as the some examples of steel structures fabricated through automatic welding by robots for box-type columns in addition to the description of the problems found in the course of fabricating those steel structures, suggesting possible counter-measures to solve them.

• Korean Journal of Environmental Agriculture
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• v.21 no.1
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• pp.50-56
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• 2002

This experiment was carried out to obtain some information about overwintering, physiological and ecological characteristics of apple snails. Another purpose of this experiment was to characterize an appetite for rice plants by apple snails and to elucidate their choice of fresh green ones (vegetables, some other crops, weeds in rice fields). The freshwater snails were found with higher population at sites abundant organic compounds such as plant debris and at regions with high temperature. They also prefer calcium-rich water. This is a naturally occurring process. Apple snails were exceptionally veil-adapted to the south regions of Korea, especially Janghang, Jangseong and Haenam, even if the temperature of winter season is cold below 0$^{\circ}C$. Apple snails were not very selective in their food choice and eat almost everything available in their environment. A snail have something called a radula in its mouth for grinding up its food. A apple snail also chews on fruits and young succulent plant barks. In case of reproduction. apple snails deposit about 157$\sim$784 (average of 321 eggs) milky white to pale orange colored eggs above the waterline. In approximately every 22.4 seconds a new egg appears. The total time needed to deposit a egg mass varies from 58 minutes$\sim$4 hours 13 minutes. Apple snails reproduct actively from May to June and from September to October. An appetite of apple snails for rice plants was the different depending on their size and glowing stage for rice plants. Apple snails had a great appetite of rice plants as well as dropwort, tomato, cabbage, radish, aquatic plants etc. They preferred to eat young rice plants and drastically quit eating rice plants of over 40 cm in height. Thus considering the food preference of apple snail for various plants including rice, they were thought to be a potentially strong predator in fields, especially, at regions with warmer winter.

• Journal of Distribution Research
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• v.17 no.1
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• pp.65-86
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• 2012

The $20^{th}$ century was the era of manufacturer brands which built higher brand equity for consumers. Consumers moved from generic products of inconsistent quality produced by local factories in the $19^{th}$ century to branded products from global manufacturers and manufacturer brands reached consumers through distributors and retailers. Retailers were relatively small compared to their largest suppliers. However, sometime in the 1970s, things began to slowly change as retailers started to develop their own national chains and began international expansion, and consolidation of the retail industry from mom-and-pop stores to global players was well under way (Kumar and Steenkamp 2007, p.2) In South Korea, since the middle of the 1990s, the bulking up of retailers that started then has changed the balance of power between manufacturers and retailers. Retailer private labels, generally referred to as own labels, store brands, distributors own private-label, home brand or own label brand have also been performing strongly in every single local market (Bushman 1993; De Wulf et al. 2005). Private labels now account for one out of every five items sold every day in U.S. supermarkets, drug chains, and mass merchandisers (Kumar and Steenkamp 2007), and the market share in Western Europe is even larger (Euromonitor 2007). In the UK, grocery market share of private labels grew from 39% of sales in 2008 to 41% in 2010 (Marian 2010). Planet Retail (2007, p.1) recently concluded that "[PLs] are set for accelerated growth, with the majority of the world's leading grocers increasing their own label penetration." Private labels have gained wide attention both in the academic literature and popular business press and there is a glowing academic research to the perspective of manufacturers and retailers. Empirical research on private labels has mainly studies the factors explaining private labels market shares across product categories and/or retail chains (Dahr and Hoch 1997; Hoch and Banerji, 1993), factors influencing the private labels proneness of consumers (Baltas and Doyle 1998; Burton et al. 1998; Richardson et al. 1996) and factors how to react brand manufacturers towards PLs (Dunne and Narasimhan 1999; Hoch 1996; Quelch and Harding 1996; Verhoef et al. 2000). Nevertheless, empirical research on factors influencing the production in terms of a manufacturer-retailer is rather anecdotal than theory-based. The objective of this paper is to bridge the gap in these two types of research and explore the factors which influence on manufacturer's private label production based on two competing theories: S-C-P (Structure - Conduct - Performance) paradigm and resource-based theory. In order to do so, the authors used in-depth interview with marketing managers, reviewed retail press and research and presents the conceptual framework that integrates the major determinants of private labels production. From a manufacturer's perspective, supplying private labels often starts on a strategic basis. When a manufacturer engages in private labels, the manufacturer does not have to spend on advertising, retailer promotions or maintain a dedicated sales force. Moreover, if a manufacturer has weak marketing capabilities, the manufacturer can make use of retailer's marketing capability to produce private labels and lessen its marketing cost and increases its profit margin. Figure 1. is the theoretical framework based on a strategic market management perspective, integrated concept of both S-C-P paradigm and resource-based theory. The model includes one mediate variable, marketing capabilities, and the other moderate variable, competitive intensity. Manufacturer's national brand reputation, firm's marketing investment, and product portfolio, which are hypothesized to positively affected manufacturer's marketing capabilities. Then, marketing capabilities has negatively effected on private label production. Moderating effects of competitive intensity are hypothesized on the relationship between marketing capabilities and private label production. To verify the proposed research model and hypotheses, data were collected from 192 manufacturers (212 responses) who are producing private labels in South Korea. Cronbach's alpha test, explanatory / comfirmatory factor analysis, and correlation analysis were employed to validate hypotheses. The following results were drawing using structural equation modeling and all hypotheses are supported. Findings indicate that manufacturer's private label production is strongly related to its marketing capabilities. Consumer marketing capabilities, in turn, is directly connected with the 3 strategic factors (e.g., marketing investment, manufacturer's national brand reputation, and product portfolio). It is moderated by competitive intensity between marketing capabilities and private label production. In conclusion, this research may be the first study to investigate the reasons manufacturers engage in private labels based on two competing theoretic views, S-C-P paradigm and resource-based theory. The private label phenomenon has received growing attention by marketing scholars. In many industries, private labels represent formidable competition to manufacturer brands and manufacturers have a dilemma with selling to as well as competing with their retailers. The current study suggests key factors when manufacturers consider engaging in private label production.