• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.181-188
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• 2019

The migration path of a multiple-generation technology that occurs during a technological substitution by a new technology is important to understanding the phenomenon of technological substitution, and can contribute to understanding the process of technological innovation. This research defines the concept of migration path and develops a model of the types of migration paths by multiple dimensions (actor, generation, and time) in a multiple-generation technology. Based on a literature review and tracking of migration paths according to multiple dimensions, the definitions and types of migration paths were provided, and the accuracy of the model was verified based on a case study of the semiconductor industry. The migration paths of suppliers are modeled with three types (switching, leapfrogging, and new entrance paths), and the migration paths of customers are modeled with four types (switching, leapfrogging, new entrance, and diffusion paths) in a multiple-generation technology. This research will be useful for understanding the migration paths in the phenomenon of technological substitution, and can be applied to other industries in addition to the semiconductor industry, including various actors. In addition, suppliers and customers can understand technological substitution and can establish a technology strategy against their competitors.

• Ocean and Polar Research
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• v.30 no.4
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• pp.453-466
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• 2008

In order to examine the generation mechanism of long ocean waves along the west coast of Korea and to understand the amplification process of the long ocean waves, sea level, atmospheric pressure and wind data observed every minute from 2007 March 29 to 2007 April 1 were analyzed and onedimensional numerical ocean model experiments were performed. An atmospheric pressure jump propagated southeastward from Backryungdo to Yeonggwang along the west coast of Korea with speed of $13{\sim}27\;m/s$ between 2007 March 30 23:00 and 2007 April 1 1:30. Average magnitude of pressure jump was 4.2 hPa. As a moving atmospheric jump propagated from north to south along the coast, long ocean waves were generated and the sea level abnormally rose or fell at Anheung, Kunsan, Wido and Yeonggwang. Average amplitude of sea level rise (or fall) was about 113.6 cm. In a one-dimensional numerical ocean model, nonlinear shallow water equations were numerically integrated and a moving atmospheric pressure jump with traveling speed of 24 m/s was used as an external force. While the atmospheric pressure jump travels over 60 m depth ocean, a long ocean wave is generated. Because the propagation speed of the atmospheric jump is almost equal to that of the long ocean wave, Proudman resonance occurs and the long ocean wave amplifies. As the atmospheric pressure jump moves into the coastal area shallower than 60 m, the speed of the long ocean wave decreases and Proudman resonance effect decreases. However, the amplitude of the long ocean wave increases and wave length becomes shorter because of shoaling effect. When the long ocean wave hits the land boundary, amplitude of the long ocean wave drastically amplifies due to reflection. Data analysis and numerical experiments suggest that the southeastward propagation of an atmospheric pressure jump over the shallow ocean, which is a necessary condition for Proudaman resonance, generated the long ocean waves along the west coast of Korea on 2007 March 31 and the ocean waves amplified due to shoaling effect in the coastal area and reflection at the shore.

• Economic and Environmental Geology
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• v.45 no.4
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• pp.407-429
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• 2012

There has been much debates on the geologic age of the sediments of the Domi Basin, since age results varied after research methods and fossil groups. This study carried out palynological analysis and seismic interpretation to establish a stratigraphy and environmental reconstruction mainly based on fossil dinoflagellates and Seismic data from the Domi-1 and Sora-1 wells. The dinocyst assemblages found enabled zonation of the well sediment sequence resulting in 4 ecozones. Index fossils among dinocysts and palynomorphic substances indicate geologic age of the well ranges from Eocene to Pleistocene, and paleoenvironment varies from freshwater to inner-neritic marine. The fossil association also suggests strong relationship to Japanese Tertiary basins in Kyushu area in terms of stratigraphy and basin developmental history.

• Journal of Animal Science and Technology
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• v.48 no.6
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• pp.777-784
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• 2006

This study was designed to investigate between the semen characteristics and sperm chromatin structure in boar with different farrowing rates and relationship between fertility by AI and results of sperm chromatin structure assay (SCSA). The CASA (computer-aided sperm analysis) and SCSA were performed with liquid semen in boars. The all SCSA parameters based on the farrowing rates by AI were significantly differ (P<0.05). The significant negative correlations (P<0.05) were observed between all SCSA parameters and farrowing rate obtained by AI in the field. In conclusion, these results suggest that the sperm parameters evaluated in these studies may be useful indicators to predict the fertility by AI.

• Korean Journal of Food Science and Technology
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• v.31 no.5
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• pp.1392-1396
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• 1999

This work was to apply the microwave energy to HTST pasteurization of milk in order to prevent undesirable quality changes due to the fouling and overheating on the surface of heat exchanger. A continuous tubulartype microwave pasteurization system was designed using a domestic microwave oven(800w and 2,450MHz). Raw milk was HTST pasteurized$(at\;72^{circ}C\;for\;15\;sec)$ by three methods; by heating in a stainless steel tube immersed in a hot water bath(MP0), by heating in a microwave cavity to a desired temperature and then holding in a hot water bath(MP1) and by both heating and holding in a microwave cavity(MP2). The microbial quality based on the total plate count and Psychotrophic bacterial count was in the order MP0, MP2 and MP1 ; however, the quality difference was not significant(p<0.05) when the initial microbial numbers were involved in the statistical analysis. In addition, the three samples pasteurized by different methods showed the similar microbial quality based on the coliform count and phosphatase activity. The similar microbial quality of the three samples supports the potential use of microwave energy for the pasteurization of milk and other fluid food products.

• Korean Journal of Head & Neck Oncology
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• v.16 no.2
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• pp.167-171
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• 2000

Objectives: To compare the outcomes of treatment with a focus on the effectiveness of the two primary techniques of radiation used for treating parotid gland malignancies. Materials and Methods: A retrospective analysis of 70 patients with parotid gland cancer treated between 1981-1997. Radiation was delivered through an ipsilateral field of high energy electron and photon in 37 patients(52.9%). Two wedge paired photon was used to treat in 33 patients(47.1%). The median dose was 60 Gy, typically delivered at 1.8-2.0Gy per fraction. The median follow-up times for surviving patients was 60 months. Results: The overall and disease free 5 year survival rates were 71.6% and 69.5%, respectively. Wedge paired photon and photon-electron treatment disease tree 5 year survival rates were 61.1% and 80.5%, respectively. Overall local failure rate was 18.6%. Local failure rate of wedge paired photon technique was higher than that of mixed beam technique. Late complication rate was 37.1%, but most of them were mild grade. Conclusion: Techniques of radiation were associated with local control. The technique of using an ipsilateral field encompassing the parotid bed and treated with high energy electrons often mixed photons was effective with minimal severe late toxicity. To irradiate deep sited tumors, we consider 3-D conformal treatment plan for well encompassing the target volume.

• Herbal Formula Science
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• v.25 no.2
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• pp.179-191
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• 2017

Objectives : Increased oxidative stress by reactive oxygen species (ROS) has been suggested as a major cause of muscle fatigue. Although several studies have demonstrated the various biological properties of Sophora flavescens Aiton, Glycyrrhiza uralensis Fischer and Dictamnus dasycarpus Turcz, but the antioxidative potentials have not been clearly demonstrated. The present study was designed to investigate the protective effects of their water and ethanol extract mixtures (medicinal herbal mixtures, MHMIXs) on hydrogen peroxide ($H_2O_2$)-induced cell damage and apoptosis in C2C12 myoblasts. Methods : Cytotoxicity was assessed by an MTT assay. Quantitative evaluation of apoptosis induction and ROS production was evaluated by flow cytometry analysis. Expression levels of apoptosis regulatory and DNA-damage proteins were detected by Western blotting. Result : The inhibition of $H_2O_2$-induced cell proliferation was effectively blocked in extracts of 3: 1: 1 (EMHMIXs-1) or 2: 2: 1 (EMHMIXs-2) of S. flavescens, G. uralensis and D. dasycarpus Turcz, ethanol extracts from various complex extracts in C2C12 myoblasts. EMHMIXs-1 and EMHMIXs-2 also effectively attenuated $H_2O_2$-induced C2C12 cell apoptosis, which was associated with the restoration of the upregulation of Bad and death receptor 4, and downregulation of XIAP and cIAP-1 induced by $H_2O_2$. In addition, these herbal mixtures significantly blocked the $H_2O_2$-induced ROS generation and phosphorylation of $p-{\gamma}H2A.X$, which suggests that they can prevent $H_2O_2$-induced cellular DNA damage. Conclusions : The results suggest that EMHMIXs-1 and EMHMIXs-2 could block the DAN damage and apoptosis of C2C12 myoblasts by oxidative stress through blocking ROS generation.

• Journal of Animal Science and Technology
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• v.44 no.1
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• pp.13-22
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• 2002

To identify the differentially expressed genes at growth stage of Hanwoo, we constructed the subtractive cDNA library from loin mRNA of 12- and 24-month old Hanwoo by PCR-based subtraction. The fourteen genes were confirmed by sequencing and reverse northern blot analysis, and they were selected as candidate of putative genes differentially expressed at the growth stage of Hanwoo. Three subtracted cDNA fragments that expressed specific signal to cDNA probe for 6-month-old loin of Hanwoo were highly homologous to those of the genes encoding EPV 20, Ca2＋ATPase, and TCTP, respectively. The nine cDNA clones showed intense signal to cDNA probe from 12-month-old loin of Hanwoo, and highly homologus to those of genes encoding VCP, HSP 70, aldolase A, MSSK1, GM-2 activator protein, ryanodine receptor, acidic ribosomal phosphoprotein p1, ADP/ATP translocase, and UCP 2, respectively. Two subtracted cDNA clones that expressed specific signal to cDNA probes for 12- and 24-month-old loin of Hanwoo were detected. One of them was highly homologus to the gene encoding ferrochelatase and the other was highly homologus to the gene encoding ADRP.

• Journal of Pharmaceutical Investigation
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• v.32 no.2
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• pp.127-133
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• 2002

Levosulpiride is the 1evo-enantiomer form of racemic sulpiride, a benzamide derivative selectively inhibiting dopaminergic $D_2$ receptors at the trigger zone both in the central nervous system and in the gastrointestinal tract. The purpose of the present study was to evaluate the bioequiva1ence of two levosulpiride tablets, Levopride (SK Pharmaceutical Co., Ltd.) and Levopid (Dae Won Pharmaceutical Co., Ltd.), according to the guidelines of Korea Food and Drug Administration (KFDA). The levosulpiride release from the two levosulpiride tablets in vitro was tested using KP VII Apparatus II method with various different kinds of dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty eight normal male volunteers, $23.82{\pm}3.26$ years in age and $69.13{\pm}8.58$ kg in body weight, were divided into two groups and a randomized $2{\times}2$ cross-over study was employed. After one tablet containing 25 mg of levosulpiride was orally administered, blood was taken at predetermined time intervals and the concentrations of levosulpiride in serum were determined using HPLC method with fluorescence detector. The dissolution profiles of two levosulpiride tablets were very similar at all dissolution media. Besides, the pharmacokinetic parameters such as $AUC_t,\;C_{max}\;and\;T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t\;and\;C_{max}$ and untransformed $T_{max}$. The results showed that the differences in $AUC_t,\;C_{max}\;and\;T_{max}$ between two tablets based on the Levopride were -1.17%, 1.20% and -1.09%, respectively. There were no sequence effects between two tablets in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log(0.8) to log(1.25) $(e.g.,\;log(0.93){\sim}log(1.07)\;and\;log(0.90){\sim}log(1.14)\;for\;AUC_t\;and\;C_{max}$, respectively). The 90% confidence interval using untransformed data was within ${\pm}20%$ $(e.g.,\;-19.47{\sim}16.20\;for\;T_{max})$. All parameters met the criteria of KFDA guideline for bioequivalence, indicating that Levopid tablet is bioequivalent to Levopride tablet.

• Environmental Engineering Research
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• v.10 no.5
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• pp.213-226
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• 2005

To treat wastewater efficiently by a one-step process of nitrogen removal, a new bacterial strain producing $N_2$ gas from ${NH_4}^+$ under an aerobic condition was isolated and identified. The cell was motile and a Gram-negative rod, and usually occurred in pairs. By 16S-rDNA analysis, the isolated strain was identified as Enterobacter asburiae with 96% similarity. The isolate showed that the capacity of $N_2$ production under an oxic condition was approximately three times higher than that under an anoxic condition. Thus, the consumption of ${NH_4}^+$ by the isolate was significantly different in the metabolism of $N_2$ production under the two different environmental conditions. The optimal conditions of the immobilized isolate for $N_2$ production were found to be pH 7.0, $30^{\circ}C$ and C/N ratio 5, respectively. Under all the optimum reaction conditions, $N_2$ production by the immobilized isolate resulted in reduction of ORP with both the consumption of DO and the drop of pH. The removal efficiencies of $COD_{Cr}$, and TN were 56.1 and 60.9%, respectively. The removal rates of $COD_{Cr}$, and TN were the highest for the first 2.5 hrs with the removal $COD_{Cr}/TN$ ratios of 32.1, and afterwards the rates decreased as reaction proceeded. For application of the immobilized isolate to a practical process of ammonium removal, a continuous operation was executed with a synthetic medium of a low C/N ratio. The continuous bioreactor system exhibited a satisfactory performance at 12.1 hrs of HRT, in which the effluent concentrations of ${NH_4}^+$-N was measured to be 15.4 mg/L with its removal efficiency of 56.0%. The maximum removal rate of ${NH_4}^+$-N reached 1.6 mg ${NH_4}^+$-N/L/hr at 12.1 hrs of HRT(with N loading rate of $0.08\;Kg-N/m^3$-carrier/d). As a result, the application of the immobilized isolate appears a viable alternative to the nitrification-denitrification processes.