• Journal of Korean Society of Forest Science
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• v.32 no.1
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• pp.73-86
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• 1976

Two individuals ($sp_1$, $sp_2$) of purple and one individual ($sd_1$) of red hearted flower were selected from 18 years old Hibiscus syriacus trees obtained from the seeds treated with colchicine, and their morphological and physiological characteristics were investigated and following results were obtained. 1. The somatic chromosome number of the selected individuals, $sp_1$, $sp_2$, and $sd_1$ were 2n=160, while that of the check tree was 2n=80, indicating that the selected individuals, $sp_1$, $sp_2$ and $sd_1$ were tetraploid. 2. Peroxidase isoenzyme bands of high activity in selected individuals, $sp_1$, $sd_1$ and check tree were mostly in cathode, fixed band was f and v bands, and frequency of each band and their activity were not different between selected individuals, $sp_1$ and $sd_1$ and check tree. 3. The flowers of $sp_1$ individual were large in size and more dark purple than check tree's. The flowers of $sp_2$ individual were not increased in size, but they were dark purple and red heart at the base of the petal was expanded to 2/3 of the petal length. The flower of $sd_1$ individual was also large and some of the red lines from the petal base were extended to 2/3 of the petal length, which was much longer than those of the check tree. 4. Thickess of leaves, length of guard cells, diameter of pollens, wood fiber lengths and woody fiber widths were all increased in $sp_1$, $sp_2$ and $sd_1$ as compared to those of the check tree. 5. Survival percentage of cuttings was 80% with $sp_1$ and 36% with $sd_1$, and their growth performance were inferior to control in their second growing season.

• Journal of Global Scholars of Marketing Science
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• v.19 no.3
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• pp.28-36
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• 2009

While existing literature has focused extensively on the strengths and weaknesses of the Chaebol and their ownership and governance, there have been few studies of Korean non-Chaebol firms. However, Lee, Lee and Pennings (2001) did not specifically investigate the competitive strategies that non-Chaebol firms use to survive against the Chaebol in the domestic Korean market. The motivation of this paper is to document, through four exploratory case studies, the successful competitive strategies of non-Chaebol Korean companies against the Chaebol and then offer some propositions that may be useful to other entrepreneurial firms as well as public policy makers. Competition and cooperation as conceptualized by product similarity and cooperative inter.firm relationship respectively, are major dimensions of firm.level marketing strategy. From these two dimensions, we develop the following $2{\times}2$ matrix, with 4 types of competitive strategies for non-Chaebol companies against the Chaebol (Fig. 1.). The non-Chaebol firm in Cell 1 has a "me-too" product for the low-end market while conceding the high-end market to a Chaebol. In Cell 2, the non-Chaebol firm partners with a Chaebol company, either as a supplier or complementor. In Cell 3, the non-Chaebol firm engages in direct competition with a Chaebol. In Cell 4, the non-Chaebol firm targets an unserved part of the market with an innovative product or service. The four selected cases such as E.Rae Electronics Industry Company (Co-exister), Intops (Supplier), Pantech (Competitor) and Humax (Niche Player) are analyzed to provide each strategy with richer insights. Following propositions are generated based upon our conceptual framework: Proposition 1: Non-Chaebol firms that have a cooperative relationship with a Chaebol will perform better than firms that do not. Proposition 1a; Co-existers will perform better than Competitors. Proposition 1b: Partners (suppliers or complementors) will perform better than Niche players. Proposition 2: Firms that have no product similarity with a Chaebol will perform better than firms that have product similarity. Proposition 2a: Partners (suppliers or complementors) will perform better than Co.existers. Proposition 2b: Niche players will perform better than Competitors. Proposition 3: Niche players should perform better than Co-existers. Proposition 4: Performance can be rank.ordered in descending order as Partners, Niche Players, Co.existers, Competitors. A team of experts was constituted to categorize each of these 216 non-Chaebol companies into one of the 4 cells in our typology. Simple Analysis of Variance (ANOVA) in SPSS statistical software was used to test our propositions. Overall findings are that it is better to have a cooperative relationship with a Chaebol and to offer products or services differentiated from a Chaebol. It is clear that the only profitable strategy, on average, to compete against the Chaebol is to be a partner (supplier or complementor). Competing head on with a Chaebol company is a costly strategy not likely to pay off for a non-Chaebol firm. Strategies to avoid head on competition with the Chaebol by serving niche markets with differentiated products or by serving the low-end of the market ignored by the Chaebol are better survival strategies. This paper illustrates that there are ways in which small and medium Korean non-Chaebol firms can thrive in a Chaebol environment, though not without risks. Using different combinations of competition and cooperation firms may choose particular positions along the product similarity and cooperative relationship dimensions to develop their competitive strategies-co-exister, competitor, partner, niche player. Based on our exploratory case-study analysis, partner seems to be the best strategy for non-Chaebol firms while competitor appears to be the most risky one. Niche players and co-existers have intermediate performance, though the former do better than the latter. It is often the case with managers of small and medium size companies that they tend to view market leaders, typically the Chaebol, with rather simplistic assumptions of either competition or collaboration. Consequently, many non-Chaebol firms turn out to be either passive collaborators or overwhelmed competitors of the Chaebol. In fact, competition and collaboration are not mutually exclusive, and can be pursued at the same time. As suggested in this paper, non-Chaebol firms can actively choose to compete and collaborate, depending on their environment, internal resources and capabilities.

• Journal of Intelligence and Information Systems
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• v.20 no.4
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• pp.121-139
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• 2014

Predicting corporate failure has been an important topic in accounting and finance. The costs associated with bankruptcy are high, so the accuracy of bankruptcy prediction is greatly important for financial institutions. Lots of researchers have dealt with the topic associated with bankruptcy prediction in the past three decades. The current research attempts to use ensemble models for improving the performance of bankruptcy prediction. Ensemble classification is to combine individually trained classifiers in order to gain more accurate prediction than individual models. Ensemble techniques are shown to be very useful for improving the generalization ability of the classifier. Bagging is the most commonly used methods for constructing ensemble classifiers. In bagging, the different training data subsets are randomly drawn with replacement from the original training dataset. Base classifiers are trained on the different bootstrap samples. Instance selection is to select critical instances while deleting and removing irrelevant and harmful instances from the original set. Instance selection and bagging are quite well known in data mining. However, few studies have dealt with the integration of instance selection and bagging. This study proposes an improved bagging ensemble based on instance selection using genetic algorithms (GA) for improving the performance of SVM. GA is an efficient optimization procedure based on the theory of natural selection and evolution. GA uses the idea of survival of the fittest by progressively accepting better solutions to the problems. GA searches by maintaining a population of solutions from which better solutions are created rather than making incremental changes to a single solution to the problem. The initial solution population is generated randomly and evolves into the next generation by genetic operators such as selection, crossover and mutation. The solutions coded by strings are evaluated by the fitness function. The proposed model consists of two phases: GA based Instance Selection and Instance based Bagging. In the first phase, GA is used to select optimal instance subset that is used as input data of bagging model. In this study, the chromosome is encoded as a form of binary string for the instance subset. In this phase, the population size was set to 100 while maximum number of generations was set to 150. We set the crossover rate and mutation rate to 0.7 and 0.1 respectively. We used the prediction accuracy of model as the fitness function of GA. SVM model is trained on training data set using the selected instance subset. The prediction accuracy of SVM model over test data set is used as fitness value in order to avoid overfitting. In the second phase, we used the optimal instance subset selected in the first phase as input data of bagging model. We used SVM model as base classifier for bagging ensemble. The majority voting scheme was used as a combining method in this study. This study applies the proposed model to the bankruptcy prediction problem using a real data set from Korean companies. The research data used in this study contains 1832 externally non-audited firms which filed for bankruptcy (916 cases) and non-bankruptcy (916 cases). Financial ratios categorized as stability, profitability, growth, activity and cash flow were investigated through literature review and basic statistical methods and we selected 8 financial ratios as the final input variables. We separated the whole data into three subsets as training, test and validation data set. In this study, we compared the proposed model with several comparative models including the simple individual SVM model, the simple bagging model and the instance selection based SVM model. The McNemar tests were used to examine whether the proposed model significantly outperforms the other models. The experimental results show that the proposed model outperforms the other models.

• Korean Journal of Weed Science
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• v.31 no.3
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• pp.221-228
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• 2011

Weed control is of fundamental importance when planting horticultural crops, particularly during the establishment phase. Weeds compete for nutrients, water and light, and can severely threaten the survival and early growth of newly planted crops. Failure to control weeds represents one of the single most important factors leading to crop loss. Knowledge on the existence of the diversity of weed species in greenhouses is of our main concern in this study in order to develop a most efficient and effective weed control strategies. Sixty-two greenhouses were surveyed in 3 cities and counties of Gyeongnam area in March to October 2009 to investigate the feature of weed occurrence in polyvinyl chloride (PVC) after harvesting of the main crops. Forty-one weed species were identified and classified to 18 families which were composed of 14 annual weeds, 18 summer annual weeds and 9 perennial weeds. On the other hand, broadleaf, grasses and sedges recorded with 30, 7 and 4 weed species, respectively. Asteraceae was the most dominant weed species (9 species) noted followed by Poaceae (7 species), Cyperaceae (4 species), Caryophyllaceae and Brassicaceae (3 species respectively) and other families have 1~2 species. The dominant weed species occurred in the greenhouse based on the summed dominance ratio. These weeds were Digitaria sanguinalis, Cyperus iria, Portulaca oleracea, Rorippa islandica, Mazus japonicas, Cardamine flexousa, and Eclipta prostrata and others. Weed occurrence in the greenhouse after horticultural crops consisted of summer annuals (4 species), winter annuals (3 species), and perennial annuals (1 specie). The dominant species occurred in tilled soil based on summed dominance ratio of weeds were Cardamine flexousa (88.1%), Eclipta prostrate (57.4%) and Portulaca oleracea (55.2%). Comparison of weed occurrence was thoroughly surveyed also in which field without PVC, weed species were Portulaca oleracea (55.2), Eclipta prostrata (57.9%) and Trigonotis peduncularis (25.1%) and field with PVC, the identified weeds were Portulaca oleracea (98.75), Trigonotis peduncularis (49.1%), and Eclipta prostrata (36.8%).

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.417-425
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• 2017

Cnidium monnieri (L.) Cusson is distributed in China and Korea, and the fruit of C. monnieri is used as traditional Chinese medicine to treat carbuncle and pain in female genitalia. In this study, we examined the anti-proliferation and cell cycle arrest effects of ethanol extracts from C. monnieri (CME) in AGS gastric cancer cells. Our results show that CME suppressed cell proliferation and induced release of lactate dehydrogenase (LDH) in AGS cells by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay and LDH assay. Cell morphology was altered by CME in a dose-dependent manner. In order to identify the cell cycle arrest effects of CME, we investigated cell cycle analysis after CME treatment. In our results, CME induced cell cycle arrest at G1 phase. Protein kinase B (Akt) plays a major role in cell survival mechanisms such as growth, division, and metastasis. Akt protein regulates various downstream proteins such as glycogen synthase kinase-$3{\beta}$ (GSK-$3{\beta}$) and tumor protein p53 (p53). Expression levels of p-Akt, p-GSK-$3{\beta}$, p53, p21, cyclin E, and cyclin-dependent kinase 2 (CDK2) were determined by Western blot analysis. Protein levels of p-Akt, p-GSK-$3{\beta}$, and cyclin E were reduced while those of p53, p21, and p-CDK2 (T14/Y15) were elevated by CME. Moreover, treatment with CME, LY294002 (phosphoinositide 3-kinase/Akt inhibitor), BIO (GSK-$3{\beta}$ inhibitor), and Pifithrin-${\alpha}$ (p53 inhibitor) showed that cell cycle arrest effects were mediated through regulation of the Akt/GSK-$3{\beta}$/p53 signaling pathway. These results suggest that CME induces cell cycle arrest at G1 phase via the Akt/GSK-$3{\beta}$/p53 signaling pathway in AGS gastric cancer cells.

• Journal of Korean Society of Forest Science
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• v.110 no.3
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• pp.406-418
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• 2021

This study was conducted to evaluate optimal storage techniques for bare root plants and container seedlings of Quercus variabilis and Zelkova serrata in order to maintain high quality of seedlings until planting. Refrigerated storage treatments were given at two temperatures (-2℃ [freezing] and 2℃ [cooling]) for nine different durations (0, 15, 30, 60, 120, 180, 240, 300, and 360 days after storage). We analyzed total nonstructural carbohydrate (TNC) content and measured shoot moisture content (SMC) during the storage stage and survival rate (SR) and dry weight during the planting stage of seedlings. The TNC content and SMC of the seedlings of the two species decreased with an increase in storage duration. The TNC content of seedlings rapidly decreased after 180~240 days of storage. The TNC reduction rate in the freezing treatment was lower than that in the cooling treatment. Also, with an increase in the storage duration of the two species, the SMC reduction rate in the cooling treatment increased in comparison with that in the freezing treatment. In both the species, the SR after planting decreased rapidly after 60 days of cooling storage and 180 days of freezing storage, respectively. The SR after planting was less than 60% when the TNC content for both the species dropped below 20 mg g^-1. In addition, the SR was lower than 80% when SMC measured before storage decreased by approximately 30% and 20% for Q. variabilis and Z. serrata, respectively. Our results suggest that cooling (1~2℃) storage is recommended for a short-term period (2 months or less), whereas freezing (-2~-4℃) storage is suitable for longer periods (2~6 months). These optimal storage techniques, allied with seedling harvesting and handling systems, will improve the quality of seedling production in nursery stages and increase seedling growth performances in plantations.

• Korean Journal of Microbiology
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• v.51 no.3
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• pp.231-240
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• 2015

In this study, a total of 16 conjugated linoleic acid (CLA) producing lactic acid bacteria (LAB) were isolated from fermented foods. Among those strains, the S48 and P1201 strains were capable of producing higher CLA contents than other LABs. The two strains were classified as Lactobacillus plantarum based on morphological, physiological, chemotaxonomic, and molecular-genetic properties. The survival rates of these strain appeared to be 59.57% and 62.22% under artificial gastric conditions after 4 h at pH 2.5, respectively. These strains produced the cis-9, trans-11, and trans-10, cis-12 CLA isomers from 8% skim milk medium supplemented with the different free LA concentration at $37^{\circ}C$ for 48 h and the production of two CLA isomers constantly increased in the growth until 48 h of incubation. After 48 h of fermentation, the levels of CLA appeared highest in steamed soy-powder milk than fresh and roasted soy-powder milks. In particular, the CLA contents were produced $183.57{\mu}g/ml$ and $198.72{\mu}g/ml$ from steamed soy-powder milk after fermentation (48 h) with S48 and P1201 strains, respectively.

• Journal of Chest Surgery
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• v.42 no.2
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• pp.175-183
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• 2009

Background: Mitral valve abnormalities in the pediatric population are rare. Mitral valve replacement or pediatric mitral lesions can cause problems such as a lack of growth potential. There re only limited experiences with mitral valve repair at any institution, so the purpose of his study is to evaluate the outcomes of mitral valve repair n pediatric patients. Material and Method: Sixty-four consecutive children (28 males and 36 females) with a mean age of $5.5{\pm}4.7$ years underwent mitral valve repair for treating their congenital mitral valve disease between January 1996 and December 2005. The patients were divided into two groups: group 1 (34 patients (53.1%)) had isolated disease (mitral anomaly with or without trial septal defect or patent ductus arteriosus) and group 2 (30 patients (46.9%)) had complex disease (mitral anomaly with concurrent intracardiac disease, except atrioventricular septal defect). Result: The overall in-hospital mortality was 6.3%; group 1 had 5.9% mortality and group 2 had 10.0% mortality. The postoperative morbidity was 18.8%; group 1 and 2 had 14.7% and 23.3% postoperative morbidity, respectively, and there as no significant difference among the groups. The median follow-up was 4.6 years range: $0.5{\sim}12.2$ years). The 10-year survival rate was 95.3%. The 10-year freedom from re-operation rate was 76.1% with 10 re-operations. The majority of the functional classifications were annular dilatation and leaflet prolapse. A mean of $2.1{\pm}1.1$ procedures per patient were performed. The echocardiography that was done at the immediate postoperative period showed a significant improvement in the mitral valve function. The follow-up echocardiographic results were significantly improved. However, mitral stenosis newly developed over time, and there ere significant differences according to the repair strategies. Conclusion: The patients who underwent mitral valve repair for congenital mitral anomalies showed good results. The follow-up echocardiography revealed satisfactory short-term and long-term results. Close follow-up is necessary to detect the development of postoperative mitral stenosis or regurgitation.

• Korean Security Journal
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• no.21
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• pp.75-94
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• 2009

Since mechanical security systems are mostly composed of electronic, information and communication devices, they have effects in the aspects of overall social environment and crime-oriented environment. Also, the importance is increasing for wireless recognition of RFID and tracing function, which will be usefully utilized in controlling the incomings and outgoings of people/vehicles or allowance, surveillance and control. This is resulting from the increase in the care for the elderly according to the overall social environment, namely, the aging society, and the number of women entering, as well as the increase in the number of heinous crimes. The purpose of this study is to examine the theoretical considerations on ubiquitous sensor network and present a direction for securities companies for their development by focusing on the technological and application areas. To present strategies of response to a new environment for security companies, First, a diversification strategy is needed for security companies. The survival of only high level of security companies in accordance with the principle of liberal market competition will bring forth qualitative growth and competitiveness of security market. Second, active promotion by security companies is needed. It is no exaggeration to say that we are living in the modern society in the sea of advertisements and propaganda. The promotional activities that emphasize the areas of activity or importance of security need to be actively carried out using the mass media to change the aware of people regarding security companies, and they need to come up with a plan to simultaneously carry out the promotional activities that emphasize the public aspect of security by well utilizing the recent trend that the activities of security agents are being used as a topic in movies or TV dramas. Third, technically complementary establishment of ubiquitous sensor network and electronic tag is needed. Since they are used in mobile electronic tag services such as U-Home and U-Health Care, they are used throughout our lives by forming electronic tag environment within safe ubiquitous sensor network based on the existing privacy guideline for the support of mobile electronic tag terminal commercialization, reduction in communication and information usage costs, continuous technical development and strengthening of privacy protection, and the system of cooperation of academic-industrial-research needs to be established among the academic world and private research institutes for these parts.

• Journal of fish pathology
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• v.18 no.1
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• pp.19-28
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• 2005

Scuticociliatosis has badly settled one of most damaging diseases during the seedling production process of olive flounder. Paralichthys olivaceus in Korea. We isolated a new type of Scuticociliate from flounder. The parasite metamorphoses to ciliate and cyst phases with each other by environmental changes and survive for a relatively long span. The ciliate was measured average 41.8 ${\mu}m$ in length and 21.0 ${\mu}m$ in width, and cyst was 17.0 ${\mu}m$ and 13.5 ${\mu}m$, respectively. Nutritional condition was determined as a major parameter of metamorphosing between ciliate and cyst stages. The ciliate transforms to a cyst stage because of food shortage, and the cyst returns to a ciliate stage with a favorite environmental condition and shows active growth and reproduction. The ciliate multiplied at the maximal density of $2.9 {\times} 10^5 {m\ell}^{-1}$cells in vitro cultivation at $15 ^{\circ}C$temperature using MS BHI medium and bacterial food sources. The ciliate could be proliferated at a 2.5 to $30 ^ \circ}C$ temperature range, pH 6 to 9, and 1 to 55 ppt salinity. Particularly, it survived over one week at $0 ^{\circ}C$temperature showing a high resistance against unfavorable environmental conditions. And the cyst survived for 320 days in the condition of $5 ^{\circ}C$with no feeding, but its survival period was markedly shortened in higher temperature conditions. The chemotherapeutants (formalin and hydrogen peroxide) were clarified as effective chemicals against the ciliate during in vitro trials, but the effect of therapeutants differed in proportion, depending upon the density and the bathing time of chemical compounds.