• Journal of Korean Society of Transportation
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• v.35 no.4
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• pp.360-373
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• 2017

The BTO-a projects is the types, which has a demand risk among the type of PPP projects in Korea. When demand risk is realized, private investor encounters financial difficulties due to lower revenue than its expectation and the government may also have a problem in stable infrastructure operation. In this regards, the government has applied various risk sharing policies in response to demand risk. However, the amount of government's risk sharing is the government's contingent liabilities as a result of demand uncertainty, and it fails to be quantified by the conventional NPV method of expressing in the text of the concession agreement. The purpose of this study is to estimate the value of investment risk sharing by the government considering the demand risk in the profit sharing system (BTO-a) introduced in 2015 as one of the demand risk sharing policy. The investment risk sharing will take the form of options in finance. Private investors have the right to claim subsidies from the government when their revenue declines, while the government has the obligation to pay subsidies under certain conditions. In this study, we have established a methodology for estimating the value of investment risk sharing by using the Black - Scholes option pricing model and examined the appropriateness of the results through case studies. As a result of the analysis, the value of investment risk sharing is estimated to be 12 billion won, which is about 4% of the investment cost of the private investment. In other words, it can be seen that the government will invest 12 billion won in financial support by sharing the investment risk. The option value when assuming the traffic volume risk as a random variable from the case studies is derived as an average of 12.2 billion won and a standard deviation of 3.67 billion won. As a result of the cumulative distribution, the option value of the 90% probability interval will be determined within the range of 6.9 to 18.8 billion won. The method proposed in this study is expected to help government and private investors understand the better risk analysis and economic value of better for investment risk sharing under the uncertainty of future demand.

• Research in Community and Public Health Nursing
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• v.7 no.1
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• pp.69-79
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• 1996

To investigate the factors related with the compliance and the treatment of the patients with pulmonary tuberculosis in urban and suburb area, we followed up all the 755 registered patients(at urban Public Health Office 544, at suburb 210) as follow from January 1,1992 to December 31, 1993. We describe the general characteristics and the characteristics related with the disease of the patients according to the area as follow. 150 patients(27.5%) were at their age of 20 to 29 years in the urban area, whereas 45 patients (21.4%) were 60 to 69 years and another 45 patients(21.4%) were 70 to 79 years in the suburb area. According to the first chest X -ray examination, 54.5% of all cases were proved to be mild in the urban area. But in the suburb area, moderate cases (44.3%) were more than mild cases(p<0.01). Follow-up X-ray's were performed more properly(p<0.05) in the urban area(94.3%) than in the suburb area(90.0%). Most cases were found in the chest X -ray examination performed by Public Health Office (p<0.01) : payable chest X-ray in the urban area (56.7%) and free chest X-ray in the suburb area(35.2%). More patients were cured in the urban area(90.8%) than in the suburb area(87.1%). The presence of supporting family member were significantly higher(p<0.05) in the urban area(79.1%) than in the suburb area(88.1%). In the analysis of the treatment efficacy, more cure ate were found in the patients cytologically confirmed to be culture (+). In the urban area, 201 culture (+) patients (93.5%) 294 culture (-) patients (89.1%) were cured. In the suburb area, 99 culture (+) patients(91.7%) and 84 culture (-) patients(82.4%) were cured. Age, the presence of supporting family member, and the socioeconomic status of the patient had significant association with the prescription compliance related with the general characteristics of the patients. Whereas, X-ray finding and AFB culture finding were the significant factors associated with the prescription compliance related with pulmonary tuberculosis (p<0.05). The cumulative compliance in the survival analysis was 92.5% in the urban area and 88.1% in suburb area, at sixth month of follow-up. Failure rate for regular drug receipt was highest at second month in the urban area(3.75%) and at fourth month in the suburb area(4.15%). In logistic regression of the factors related with the tratment result, first X-ray examination and prescription compliance were significantly associated in the urban area(p<0.05). However, there is no factor significantly associated with the treatment result in the suburb area. It could be explained by too small size of the sample. In logistic regression of the factors related with the prescription compliance, first chest X-ray, sputum culture outcome and the presence of supporting family member were significant variables in the urban area(p<0.05). Most patients with family member were proved to be compliant with the prescription. This shows that it is important for the patients with long-lasting ilnesses to have supporting family member. Therefore, to improve prescription compliance we should strengthen the health education before the initiation of treatment and take special interest in the patients without supporting family member.

• Journal of dental hygiene science
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• v.10 no.3
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• pp.147-153
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• 2010

The purpose of this study was to investigate the correlation between food intake pattern body component bone mineral density(BMD) and dental caries experience of college women and we wanted to determine the correlation of these factors with dental caries experience. Research was conducted to offer basic data to develope a nutritional program for the future prevention from oral disease. The subjects in this study were 132 college women who participated in the food intake survey and who's body component and BMD was measured. The statistical analysis was done by using the SPSS 15.0 program. The results of this study were as follows; 1. The food intake pattern was not directly correlated with DMFT index. 2. The body component was not directly correlated with DMFT index. 3. The SOS, BQI was directly correlated with DMFT index(p<0.05). 4. T-score of BMD had the greatest influence on DMFT index(p<0.05). Above results indicated that bone mineral density are related with the incidence of dental caries experience and further research is necessary to develop a nutritional and health promotional program in order to prevent oral illness.

• Journal of Digital Convergence
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• v.18 no.10
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• pp.81-93
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• 2020

This study is based on workplace learning, which has revealed its significant influence in the previous enterprise case studies. Why do small business owners have the opportunity to participate in workplace learning based on authenticity? It was intended to clarify whether it was necessary and to increase the growth and development potential of small business owners based on its contents. Moreover, this study is focused on identifying the influence of workplace learning on management performance through this series of processes. In order to investigate the influence of small enterprise workplace learning on management performance, research hypotheses were set based on a review of previous studies, and empirical analysis was carried out. A total of 203 questionnaires were empirically analyzed using SPSS 18.0 program. As a result, first, workplace learning had partially significant positive influence on job satisfaction. Second, workplace learning had significant positive influence on management performance. Third, job satisfaction had significant positive influence on management performance. Fourth, job satisfaction had partial mediating effect in the relationship between workplace learning and management performance. The analysis result showed that among sub-factors of workplace learning, only formal learning did not affect job satisfaction and that job satisfaction did not have mediating effect in the relationship between formal learning and management performance. According to analysis, this was because in poor small enterprise environments, opportunities to participate in formal learning like external training or in-house training were not kept. In other words, poor small enterprise environments were plainly revealed from the managerial, economic and social standpoint. Therefore, there is a need to establish the foundation of growth for them to solve problems and develop win-win development capabilities and an institutional system that can make a contribution to policy and education, and management, by helping small enterprises keep opportunities to participate in workplace learning. In spite of these significant study results, there can be a limitation. For improving this limitation, further research will need to target diverse fields focusing on samples, which can explain relations of many different variables. Also, working-level relation research connected to studies that can highly enhance management performance will be required.

• Journal of Intelligence and Information Systems
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• v.23 no.3
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• pp.139-153
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• 2017

Corporate bankruptcy can cause great losses not only to stakeholders but also to many related sectors in society. Through the economic crises, bankruptcy have increased and bankruptcy prediction models have become more and more important. Therefore, corporate bankruptcy has been regarded as one of the major topics of research in business management. Also, many studies in the industry are in progress and important. Previous studies attempted to utilize various methodologies to improve the bankruptcy prediction accuracy and to resolve the overfitting problem, such as Multivariate Discriminant Analysis (MDA), Generalized Linear Model (GLM). These methods are based on statistics. Recently, researchers have used machine learning methodologies such as Support Vector Machine (SVM), Artificial Neural Network (ANN). Furthermore, fuzzy theory and genetic algorithms were used. Because of this change, many of bankruptcy models are developed. Also, performance has been improved. In general, the company's financial and accounting information will change over time. Likewise, the market situation also changes, so there are many difficulties in predicting bankruptcy only with information at a certain point in time. However, even though traditional research has problems that don't take into account the time effect, dynamic model has not been studied much. When we ignore the time effect, we get the biased results. So the static model may not be suitable for predicting bankruptcy. Thus, using the dynamic model, there is a possibility that bankruptcy prediction model is improved. In this paper, we propose RNN (Recurrent Neural Network) which is one of the deep learning methodologies. The RNN learns time series data and the performance is known to be good. Prior to experiment, we selected non-financial firms listed on the KOSPI, KOSDAQ and KONEX markets from 2010 to 2016 for the estimation of the bankruptcy prediction model and the comparison of forecasting performance. In order to prevent a mistake of predicting bankruptcy by using the financial information already reflected in the deterioration of the financial condition of the company, the financial information was collected with a lag of two years, and the default period was defined from January to December of the year. Then we defined the bankruptcy. The bankruptcy we defined is the abolition of the listing due to sluggish earnings. We confirmed abolition of the list at KIND that is corporate stock information website. Then we selected variables at previous papers. The first set of variables are Z-score variables. These variables have become traditional variables in predicting bankruptcy. The second set of variables are dynamic variable set. Finally we selected 240 normal companies and 226 bankrupt companies at the first variable set. Likewise, we selected 229 normal companies and 226 bankrupt companies at the second variable set. We created a model that reflects dynamic changes in time-series financial data and by comparing the suggested model with the analysis of existing bankruptcy predictive models, we found that the suggested model could help to improve the accuracy of bankruptcy predictions. We used financial data in KIS Value (Financial database) and selected Multivariate Discriminant Analysis (MDA), Generalized Linear Model called logistic regression (GLM), Support Vector Machine (SVM), Artificial Neural Network (ANN) model as benchmark. The result of the experiment proved that RNN's performance was better than comparative model. The accuracy of RNN was high in both sets of variables and the Area Under the Curve (AUC) value was also high. Also when we saw the hit-ratio table, the ratio of RNNs that predicted a poor company to be bankrupt was higher than that of other comparative models. However the limitation of this paper is that an overfitting problem occurs during RNN learning. But we expect to be able to solve the overfitting problem by selecting more learning data and appropriate variables. From these result, it is expected that this research will contribute to the development of a bankruptcy prediction by proposing a new dynamic model.

• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.4
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• pp.42-51
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• 2020

This study was performed to support the 6th forest basic planning by Korea Forest Service as predicting the change of forestland area by the transition of land use type in the future over 35 years in South Korea. It is very important to analyze upcoming forestland area change for future forest planning because forestland plays a basic role to predict forest resources change for afforestation, production and management in the future. Therefore, the transitional interaction between land use types in future of South Korea was predicted in this study using econometrical models based on past trend data of land use type and related variables. The econometrical model based on maximum discounted profits theory for land use type determination was used to estimate total quantitative change by forestland, agricultural land and urban area at national scale using explanatory variables such as forestry value added, agricultural income and population during over 46 years. In result, it was analyzed that forestland area would decrease continuously at approximately 29,000 ha by 2027 while urban area increases in South Korea. However, it was predicted that the forestland area would be started to increase gradually at 170,000 ha by 2050 because urban area was reduced according to population decrement from 2032 in South Korea. We could find out that the increment of forestland would be attributed to social problems such as urban hollowing and localities extinction phenomenon by steep decrement of population from 2032. The decrement and increment of forestland by unbalanced population immigration to major cities and migration to localities might cause many social and economic problems against national sustainable development, so that future strategies and policies for forestland should be established considering such future change trends of land use type for balanced development and reasonable forestland use and conservation.

• Clean Technology
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• v.28 no.3
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• pp.218-226
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• 2022

As a result of the recent social transformation towards a hydrogen economy and carbon-neutrality, the demands for hydrogen energy have been increasing rapidly worldwide. As such, eco-friendly hydrogen production technologies that do not produce carbon dioxide (CO₂) emissions are being focused on. Among them, ammonia (NH₃) is an economical hydrogen carrier that can easily produce hydrogen (H₂). In this study, Ru/Al₂O₃ catalyst coated onmetallic monolith for hydrogen production from ammonia was prepared by a dip-coating method using a catalyst slurry mixture composed of Ru/Al₂O₃ catalyst, inorganic binder (alumina sol) and organic binder (methyl cellulose). At the optimized 1:1:0.1 weight ratio of catalyst/inorganic binder/organic binder, the amount of catalyst coated on the metallic monolith after one cycle coating was about 61.6 g L^-1. The uniform thickness (about 42 ㎛) and crystal structure of the catalyst coated on the metallic monolith surface were confirmed through scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Also, a numerical optimization regression equation for NH3 conversion according to the independent variables of reaction temperature (400-600 ℃) and gas hourly space velocity (1,000-5,000 h^-1) was calculated by response surface methodology (RSM). This model indicated a determination coefficient (R²) of 0.991 and had statistically significant predictors. This regression model could contribute to the commercial process design of hydrogen production by ammonia decomposition.

• Journal of the Korean Geographical Society
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• v.38 no.2
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• pp.312-323
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• 2003

This writer absolutely agrees with the government that regional disequilibrium is severe enough to consider moving the administrative capital. Pursuing this course solely to establish a balanced development, however, is not a convincing enough reason. The capital city is directly related to not only the social and economic situation but, much more importantly, to the domestic political situation as well. In the mid-1970s, the proposal by the Third Republic to move the capital city temporarily was based completely on security reasons. At e time, the then opposition leader Kim, Dae-jung said that establishing a safe distance from the demilitarized zone(DMZ) reflected a typically military decision. His view was that retaining the capital city close to the DMZ would show more consideration for the will of the people to defend their own country. In fact, independent Pakistan moved its capital city from Karachi to Islamabad, situated dose to Kashmir the subject of hot territorial dispute with India. It is regrettable that no consideration has been given to the urgent political situation in the Korean peninsula, which is presently enveloped in a dense nuclear fog. As a person requires health to pursue his/her dream, a country must have security to implement a balanced territorial development. According to current urban theories, the fate of a country depends on its major cities. A negligently guarded capital city runs the risk of becoming hostage and bringing ruin to the whole country. In this vein, North Koreas undoubted main target of attack in the armed communist reunification of Korea is Seoul. For the preservation of our state, therefore, it is only right that Seoul must be shielded to prevent becoming hostage to North Korea. The location of the US Armed Forces to the north of the capital city is based on the judgment that defense of Seoul is of absolute importance. At the same time, regardless of their different standpoints, South and North Korea agree that division of the Korean people into two separate countries is abnormal. Reunification, which so far has defied all predictions, may be realized earlier than anyone expects. The day of reunification seems to be the best day for the relocation of the capital city. Building a proper capital city would take at least twenty years, and a capital city cannot be dragged from one place to another. On the day of a free and democratic reunification, a national agreement will be reached naturally to find a nationally symbolic city as in Brazil or Australia. Even if security does not pose a problem, the governments way of thinking would not greatly contribute to the balanced development of the country. The Chungcheon region, which is earmarked as the new location of the capital city, has been the greatest beneficiary of its proximity to the capital region. Not being a disadvantaged region, locating the capital city there would not help alleviate regional disparity. If it is absolutely necessary to find a candidate region at present, considering security, balanced regional development and post-reunification scenario of the future, Cheolwon area located in the middle of the Korean peninsula may be a plausible choice. Even if the transfer of capital is delayed in consideration of the present political conflict between the South and the North Koreas, there is a definite shortcut to realizing a balanced regional development. It can be found not in the geographical dispersal of the central government, but in the decentralization of power to the provinces. If the government has surplus money to build a new symbolic capital city, it is only right that it should improve, for instance, the quality of drinking water which now everyone eschews, and to help the regional subway authority whose chronic deficit state resoled in a recent disastrous accident. And it is proper to time the transfer of capital city to coincide with that of the reunification of Korea whenever Providence intends.