• Asia pacific journal of information systems
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• v.19 no.2
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• pp.157-178
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• 2009

Corporate credit rating is a very important factor in the market for corporate debt. Information concerning corporate operations is often disseminated to market participants through the changes in credit ratings that are published by professional rating agencies, such as Standard and Poor's (S&P) and Moody's Investor Service. Since these agencies generally require a large fee for the service, and the periodically provided ratings sometimes do not reflect the default risk of the company at the time, it may be advantageous for bond-market participants to be able to classify credit ratings before the agencies actually publish them. As a result, it is very important for companies (especially, financial companies) to develop a proper model of credit rating. From a technical perspective, the credit rating constitutes a typical, multiclass, classification problem because rating agencies generally have ten or more categories of ratings. For example, S&P's ratings range from AAA for the highest-quality bonds to D for the lowest-quality bonds. The professional rating agencies emphasize the importance of analysts' subjective judgments in the determination of credit ratings. However, in practice, a mathematical model that uses the financial variables of companies plays an important role in determining credit ratings, since it is convenient to apply and cost efficient. These financial variables include the ratios that represent a company's leverage status, liquidity status, and profitability status. Several statistical and artificial intelligence (AI) techniques have been applied as tools for predicting credit ratings. Among them, artificial neural networks are most prevalent in the area of finance because of their broad applicability to many business problems and their preeminent ability to adapt. However, artificial neural networks also have many defects, including the difficulty in determining the values of the control parameters and the number of processing elements in the layer as well as the risk of over-fitting. Of late, because of their robustness and high accuracy, support vector machines (SVMs) have become popular as a solution for problems with generating accurate prediction. An SVM's solution may be globally optimal because SVMs seek to minimize structural risk. On the other hand, artificial neural network models may tend to find locally optimal solutions because they seek to minimize empirical risk. In addition, no parameters need to be tuned in SVMs, barring the upper bound for non-separable cases in linear SVMs. Since SVMs were originally devised for binary classification, however they are not intrinsically geared for multiclass classifications as in credit ratings. Thus, researchers have tried to extend the original SVM to multiclass classification. Hitherto, a variety of techniques to extend standard SVMs to multiclass SVMs (MSVMs) has been proposed in the literature Only a few types of MSVM are, however, tested using prior studies that apply MSVMs to credit ratings studies. In this study, we examined six different techniques of MSVMs: (1) One-Against-One, (2) One-Against-AIL (3) DAGSVM, (4) ECOC, (5) Method of Weston and Watkins, and (6) Method of Crammer and Singer. In addition, we examined the prediction accuracy of some modified version of conventional MSVM techniques. To find the most appropriate technique of MSVMs for corporate bond rating, we applied all the techniques of MSVMs to a real-world case of credit rating in Korea. The best application is in corporate bond rating, which is the most frequently studied area of credit rating for specific debt issues or other financial obligations. For our study the research data were collected from National Information and Credit Evaluation, Inc., a major bond-rating company in Korea. The data set is comprised of the bond-ratings for the year 2002 and various financial variables for 1,295 companies from the manufacturing industry in Korea. We compared the results of these techniques with one another, and with those of traditional methods for credit ratings, such as multiple discriminant analysis (MDA), multinomial logistic regression (MLOGIT), and artificial neural networks (ANNs). As a result, we found that DAGSVM with an ordered list was the best approach for the prediction of bond rating. In addition, we found that the modified version of ECOC approach can yield higher prediction accuracy for the cases showing clear patterns.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.783-788
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• 2016

Excessive intake of trans fats is a risk factor for cardiovascular diseases. Previously, we showed that green tea extract lowers intestinal absorption of cholesterol and elaidic acid in rats. This study was conducted to investigate a possible role for sorghum extract on lymphatic absorption of trans fat and cholesterol in rats. Adult male rats with lymph cannulae were infused at a rate of 3.0 mL/h for 8 h via a duodenal catheter with a lipid emulsion containing $146.4{\mu}mol$ of trielaidin, $36.8{\mu}mol$ of trilinoelaidin, $452.0{\mu}mol$ of triolein, $1.0{\mu}Ci$ cholesterol labeled with $^{14}C$ ($^{14}C-cholesterol$), $20.7{\mu}mol$ of cholesterol, and $396.0{\mu}mol$ of Na-taurocholate without or with 100.0 mg of sorghum extract in phosphate-buffered saline buffer (pH 6.4). Lymph was collected hourly for 8 h. No significant difference was noted in lymph flow. However, the lymphatic absorption of elaidic acid and linoelaidic acid for 8 h was significantly lower in rats infused with sorghum extract than in those infused with no sorghum extract. Further, lymphatic absorption of $^{14}C-cholesterol$ was reduced by sorghum extract, which was observed previously. These data indicate that sorghum extract has an inhibitory effect on the intestinal absorption of trans fat and cholesterol. The mechanism(s) by which sorghum extract lowers intestinal absorption of trans fat warrants further study.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.4
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• pp.211-216
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• 2018

This study was intended to analyze the effects of the selection of excellent design product by the KIDP(Korea Institute of Design Promotion) on the business performance of the company focused on the start-up with relatively low competitiveness. According to the statistics of KIDP in 2013, a design accounted for 27.53% of the factors affecting the sales of products and a design was the most important factor among the factors affecting the sales of products for the small sized company in terms of the scale of company. In addition, looking at the trend by industry in the data collected for this study, the technology-based industry showed a relatively higher growth rate than the retail industry and other industries. In this study, the author surveyed 186 companies of the companies that recognized the importance of design in difficult management conditions and received excellent design product certificate from KIDP(2013, 2014 and 2015) and empirically verified whether there was any difference in business performance between the start-ups with a business history of less than 7 years and the ongoing firms with a business history of more than 7 years. To evaluate the value of design, we used analytical method of measuring related values by comparison between groups. In addition, we also analyzed the difference in business performance(sales) between manufacturing companies, where the role of design was relatively large, and non-manufacturing companies among companies that received the excellent design product certificate. We have established a study hypothesis that the selection of excellent design product by the KIDP would have more positive effect on the business performance(sales) of the start-up compared to the ongoing firm, and conducted an empirical analysis by comparing both the year before and the year after the selected year. As a result, we found that the selection of excellent design product by the KIDP has a positive effect on the business performance of the start-up, and the selection of excellent design product has a significant effect on the difference in business performance between manufacturing and non-manufacturing companies. This study was conducted in the hope that the government actively supports the design-related policies so that the selection of excellent design product become an important indicator of the business performance of the start-up, and thus the design management will be a way to enhance the competitiveness of the start-up.

• Korean Journal of Cognitive Science
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• v.27 no.3
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• pp.441-467
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• 2016

This fMRI study is aim to investigate effects of competitive environment in cognitive empathic process in human brain. Empathy is known as a crucial factor for human's adaptive behavior in aspects of social cognition and it is almost automatic process, on the other hand competitive situation is psychologically devastated environment to win someone for getting rewards. We hypnotized that reading and understanding of other person's mind are a specific characteristic related to survival evolutionarily, however competition would have an effect on the empathic cognitive process because of mechanisms of competition. To manipulate the competitive atmosphere, one researcher took a role of competitor against participants and they were instructed to get monetary rewards when their performance was better than a competitor. 21 participants(9 males and 12 females) performed to judge the emotional valence of the empathic task consisted of illustrated images with various situation could be experienced in real world as on $1^{st}$ person perspective in both competitive and non-competitive condition, and did same performance with objects stimulus in control condition. In order to examine the competition effects on empathic process,, hemodynamic response were obtained during fMRI session and the imaging data were analyzed to identify brain regions where responses to each condition across the two consecutive runs. Participants' reaction time in competitive condition was faster statistically significant than non-competitive one. Activation for competitive condition increased in the following areas: ACC, mPFC, SMG, thalamus extended caudate and Nacc, parahippocampal gyrus, and for non-competitive condition increased paracingulate gyrus, temporal pole, vmPFC, superior occipital gyrus. As a result of regression analysis using empathic scores as covariance, the rSMG, IFG, fusiform gyrus, thalamus, putamen were correlated with higher empathic levels, and TPJ were correlated with lower empathic scores. We suggest that these observations could mean competitive environment have an effect on neural base of cognitive empathic process.

• Restorative Dentistry and Endodontics
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• v.27 no.5
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• pp.463-472
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• 2002

Bacterial lipopolysaccharide (LPS) plays a major role in stimulating the synthesis and release of the principal osteoclast-activating cytokines, namely, interleukin 1 and tumor necrosis factor-$\alpha$ from immune cells. Although rnonocytes/macrophages are the main producers of these cytokines, recent evidence has indicated that polymorphonuclear leukocytes (PMN) have the ability to release IL-1 and TNF-$\alpha$. Calcium hydroxide has been shown to be an effective medicament in root canal infections, reducing the microbial titre within the canal. It has been proposed that the therapeutic effect of Ca(OH)$_2$ may also be the result of direct inactivation of LPS. The purpose of this study was to investigate whether treatment of Porphyromonas endodontalis LPS with calcium hydroxide alters its biological action as measured by human PMN secretion of IL-1 and TNF-$\alpha$, and it was compared with Escherichia coli LPS. P. endodontalis ATCC 35406 was cultured in anaerobic condition, and LPS was extracted using the hot-phenol water extraction method and purified. Purchased E. coli LPS was also purified. 100 $\mu\textrm{g}$/ml of each LPS in pyrogen free water were incubated with 25mg/ml Ca(OH)$_2$ at 37$^{\circ}C$ for 7 days. The supernatants were subjected to ultrafiltration, and the isolates were lyophilized and weighed. PMNs were obtained from peripheral blood by centrifugation layered over Lymphoprep. The cells were resuspended (4$\times$10$^6$ cells/ml) in RPMI 1640 followed by treatment with various concentrations of LPS (0, 0.1, 1, 10$\mu\textrm{g}$/ml) for 24 hours at 37$^{\circ}C$ in 5% $CO_2$ incubator. The supernatants of cells were collected and the levels of IL-1$\alpha$, IL=1$\beta$ and TNF-$\alpha$ were measured by enzyme-linked immunosorbent assay. The results were as follows ; 1. The levels of IL-1$\alpha$, IL-1$\beta$, TNF-$\alpha$ from PMN treated with each LPS were significantly higher than those released from unstimulated PMN of the control group (p<0.05). 2. The levels of all three cytokines released from PMN stimulated with each calcium hydroxide treated LPS were significantly lower than those released from PMN stimulated with each untreated LPS (p<0.05), while they were not significantly different from those released from unstimulated PMN of the control group (p>0.05) 3. The levels of secretion for all three cytokines were affected in a dose-dependent manner in PMN stimulated with each LPS (p<0.05), but not in PMN stimulated with each calcium hydroxide treated LPS (p>0.05). 4. The levels of all three cytokines released from PMN stimulated with p. endodontalis LPS were significantly lower than those released from PMN stimulated with E coli LPS (p<0.05).

• Clinical and Experimental Pediatrics
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• v.48 no.2
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• pp.197-203
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• 2005

Purpose : Changes in metalloproteinases(MMP) activity have been demonstrated in several disease states, including rheumatoid arthritis and tumor metastasis. More importantly, increased myocardial MMP activity has been reported to occur in both clinical and experimental forms of dilated cardiomyopathy. There was no report about MMP in adriamycin(ADR)-induced cardiomyopathy. The purpose of this study was to investigate gene expression of MMP and tissue inhibitor of metalloproteinases(TIMP) in ADR-induced cardiomyopathy and clarify the relationship between MMP and cytokines. Methods : Male Sprague-Dawley rats were divided into two groups. The first group was control. The second group was given intraperitoneal injections of ADR(5 mg/kg) twice a week over two weeks. Serum concentrations of MMP, TIMP, interleukin(IL)-6 and tumor necrosis factor(TNF)-${\alpha}$ were measured. RNA extraction was performed from frozen rat hearts. Reverse transcription polymerase chain reaction(RT-PCR) was employed. cDNA Microarray analysis was performed by using a set of 5,184 sequence-verified rat cDNA clones. Results : Serum MMP and TIMP levels were not significantly different between the two groups. IL-6 was $36.8{\pm}2.8pg/mL$ and TNF-${\alpha}$ $2.2{\pm}2.7pg/mL$ in the ADR group. They were significantly higher than in the control group. Serum MMP correlated significantly with TNF-${\alpha}$(r=0.41, P<0.05). There was no gene expression of MMP, IL-6 or TNF-${\alpha}$ in the hearts of both groups. Gene expression of TIMP was significantly depressed in the hearts of the ADR group. Conclusion : These results suggested a potential role for TNF-${\alpha}$ in the regulation of extracellular matrix remodeling in ADR induced cardiomyopathy. Rapid screening of multiple decreased gene expression by DNA chip may be a useful diagnostic test to detect early cardiac injury before developing ADR induced cardiomyopathy.

• Clinical and Experimental Pediatrics
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• v.53 no.4
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• pp.560-564
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• 2010

Purpose : Electroencephalography (EEG) findings can play a critical role in a variety of decisions, including initiation and withdrawal of antiepileptic drugs (AEDs) therapy. Interictal epileptiform discharges (IEDs) are predictor of recurrent seizures. We investigated IEDs in EEG after AED therapy and related factors in epileptic children. Methods : The subjects were 257 children [151 males and 106 females; age, 6.79 (3.40) years; duration of therapy, 2.48 (1.85) years] diagnosed with epilepsy at the Department of Pediatrics, Pusan National University Hospital between January 2001 and December 2007, who received AEDs for more than 6 months. EEG was performed at the intervals of 6-12 months. We divided patients into 4 groups according to IED detection before and after AEDs treatment. Related clinical factors, including gender, age at the start of treatment, seizure type, cause of seizure, AED frequency, seizure control, duration of AED therapy, and background activity were investigated in the 4 groups. Results : Generalized epilepsy was relatively frequen in patients who did not show IEDs in last follow-up EEG. There were no clinically significant differences according to gender, age at the start of treatment, cause of seizure, AED frequency, seizure control, duration of AED medication, and background activity in the 4 groups ($P$>0.05). Conclusion : IEDs changed after AED treatment in one-third of the patients. Generalized epilepsy is positive factor for negative IEDs in last follow-up EEG.

• Korean Journal of Psychosomatic Medicine
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• v.21 no.2
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• pp.106-113
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• 2013

Objectives: The purpose of this study was to examine the characteristics and the psychosocial factors associated to the referral to psychiatric care in the suicide attempters visiting emergency center. Methods: We conducted a systematic chart review of 377 suicidal attempters visiting emergency center of the Korea University Ansan Hospital between January 2008 and December 2011. We gathered a data contain 20 items including psychosocial characteristics and factors related to suicide and factors related to psychiatric treatment. Multivariate logistic regression models were fitted to data to estimate the unique effects of sex, drunken status, companion, suicidal methods, place of suicide and current use of psychiatric medication on the referral to psychiatric care. Results: The female gender(OR=1.63, 95% CI=0.99-2.69), suicidal attempts at home(OR=3.40, 95% I= 1.21-9.56) and drunken state at visit(OR=2.34, 95% CI=1.10-5.01) are the factors that predict the risk of the non-referral of the patients to psychiatric intervention. Place of suicidal attempt was the most important factor do play a role in determining whether referral to psychiatric care will take place or not. Current use of psychiatric medication showed a trend toward significance(p=0.08, OR=1.67, 95% CI=0.95-2.95). Conclusions: These results suggest that when deciding whether to adapt or to refuse the referral to psychiatric care, the factors such as suicidal intent, lethality of suicide methods, familiar factors and alcohol may contribute onto the referral to psychiatric care. Additional research is required to investigate an association of these factors with referral to psychiatric care.

• Journal of Distribution Science
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• v.10 no.7
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• pp.33-41
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• 2012

The purpose of this study is to analyse the state of the energy industry and to determine the efficiency of its functioning on the basis of energy conservation principle and application of innovative technologies aimed at improving the ecological modernisation of agricultural sectors of Kazakhstan. The research methodology is based on an integrated approach of financial and economic evaluation of the effectiveness of the investment project, based on calculation of elasticity, total costs and profitability, as well as on comparative, graphical and system analysis. The current stage is characterised by widely spread restructuring processes of electric power industry in many countries through introduction of new technical installations of energy facilities and increased government regulation in order to enhance the competitive advantage of electricity market. Electric power industry features a considerable value of creating areas. For example, by providing scientific and technical progress, it crucially affects not only the development but also the territorial organisation of productive forces, first of all the industry. In modern life, more than 90% of electricity and heat is obtained by Kazakhstan's economy by consuming non-renewable energy resources: different types of coal, oil shale, oil, natural gas and peat. Therefore, it is significant to ensure energy security, as the country faces a rapid fall back to mono-gas structure of fuel and energy balance. However, energy resources in Kazakhstan are spread very unevenly. Its main supplies are concentrated in northern and central parts of the republic, and the majority of consumers of electrical power live in the southern and western areas of the country. However, energy plays an important role in the economy of industrial production and to a large extent determines the level of competitive advantage, which is a promising condition for implementation of energy-saving and environmentally friendly technologies. In these circumstances, issues of modernisation and reforms of this sector in Kazakhstan gain more and more importance, which can be seen in the example of economically sustainable solutions of a large local monopoly company, significant savings in capital investment and efficiency of implementation of an investment project. A major disadvantage of development of electricity distribution companies is the prevalence of very high moral and physical amortisation of equipment, reaching almost 70-80%, which significantly increases the operating costs. For example, while an investment of 12 billion tenge was planned in 2009 in this branch, in 2012 it is planned to invest more than 17 billion. Obviously, despite the absolute increase, the rate of investment is still quite low, as the total demand in this area is at least more than 250 billion tenge. In addition, industrial infrastructure, including the objects of Kazakhstan electric power industry, have a tangible adverse impact on the environment. Thus, since there is a large number of various power projects that are sources of electromagnetic radiation, the environment is deteriorated. Hence, there is a need to optimise the efficiency of the organisation and management of production activities of energy companies, to create and implement new technologies, to ensure safe production and provide solutions to various environmental aspects. These are key strategic factors to ensure success of the modern energy sector of Kazakhstan. The contribution of authors in developing the scope of this subject is explained by the fact that there was not enough research in the energy sector, especially in the view of ecological modernisation. This work differs from similar works in Kazakhstan in the way that the proposed method of investment project calculation takes into account the time factor, which compares the current and future value of profit from the implementation of innovative equipment that helps to bring it to actual practise. The feasibility of writing this article lies in the need of forming a public policy in the industrial sector, including optimising the structure of energy disbursing rate, which complies with the terms of future modernised development of the domestic energy sector.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.3
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• pp.323-330
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• 2008

The study presents the results of 1,4-dioxane degradation using zero valent (Fe$^0$) or Fe$^{2+}$ ions with and without UV. During the reaction, the change of [Fe$^{2+}$] and [Fe$^{2+}$]/[Fe(t)], the concentration ratio of ferrous ion to total iron ion in solution was measured. Less than 10% degradation of 1,4-dioxane was observed by UV-only, Fe$^0$-only, and Fe$^{2+}$-only conditions, and also the changes of [Fe$^{2+}$] and [Fe$^{2+}$]/[Fe(t)] were minimal in each reaction. However, the oxidation of Fe$^0$ was enhanced with the irradiation of UV by approximately 25% and the improvement of 1,4-dioxane degradation was observed. Fenton reaction ($Fe^{2+}+H_2O_2$) showed higher degradation efficiency of 1,4-dioxane until 90 min, which of the degradation was stopped after that time. In the reaction of Fe$^{2+}$ and UV, the ratio of [Fe$^{2+}$]/[Fe(t)] decreased then slowly increased after a certain time indicating the reduction of Fe3+ to Fe$^{2+}$. In case of Fe$^0$ in the presence of UV, the first-order rate constant was found to be 1.84$\times$10$^{-3}$ min$^{-1}$ until 90 min, and then changed to 9.33$\times$10$^{-3}$ min$^{-1}$ when the oxidation of Fe$^{2+}$ mainly occurred. In this case [Fe$^{2+}$]/[Fe(t)] kept decreasing for the reaction. However, the addition of perchlortae (ClO$_4^-$) in the reaction of Fe$^0$ and UV induced the continuous increase of [Fe$^{2+}$]/[Fe(t)] ratio. The results mean the primary degradation factor of 1,4-dioxane is the oxidation by the radicals generated from the redox reaction between Fe$^{2+}$ and Fe$^{3+}$. Also, both UV and ClO$_4^-$ played the role inducing the reduction of Fe$^{3+}$, which is important to degrade 1,4-dioxane by enhancing the generation of radicals.