• Journal of the Korean Association of Geographic Information Studies
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• v.23 no.4
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• pp.140-155
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• 2020

This study was conducted to identify the location characteristics of infected farms in the areas where livestock diseases were clustered(southern Gyeonggi-do and Chungcheong-do), analyze the probability of disease occurrence in poultry farms, find out the areas corresponding to the conditions, and use them as the basis for prevention of livestock diseases, selection of discriminatory prevention zones, and establishment of prevention strategies and as the basic data for complementary measures. The increase of one poultry farm within a radius of 3-kilometers increases the risk of HPAI infection by 10.9% compared to the previous situation. The increase of 1m in distance from major roads with two lanes or more reduces the probability of HPAI infection by 0.001% compared to the previous situation. If the distance of the poultry farm located with 15 kilometers from a major migratory bird habitat increases by 15 to 30 kilometers, the chance of infection with HPAI is reduced by 46.0%. And if the distance of the same poultry farm increase by more than 30 kilometers, the chances of HPAI infection are reduced by 88.5%. Based on the results of logistic regression, the predicted probability was generated and the actual area of the location condition with 'more than 15 poultry farms within 3km a radius of, within 1km distance from major roads, and within 30km distance from major migratory birds habitat was determined and the infection rate was measured. It is expected that the results of this study will be used as basic data for preparing the data and supplementary measures when the quarantine authorities establish discriminatory quarantine areas and prevention strategies, such as preventive measures for the target areas and farms, or control of vehicles, by identifying the areas where livestock diseases are likely to occur in the region.

• Korean Journal of Remote Sensing
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• v.36 no.6_3
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• pp.1721-1732
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• 2020

Elementary school students spend a lot of time in a school and are more exposed to indoor air pollution. Also the students are physically growing and have a relatively high respiratory rate per unit weight compared to adults, so it is known that there is a high sensitivity to indoor air pollution. Therefore, indoor air quality in a school is becoming an important factor for the student's health. In this study, a correlation analysis using levels of indoor and outdoor Particulate Matter (PM) measured from five elementary schools in Seoul was performed to evaluate the effect of outdoor PM on indoor PM. PM ratio and indoor/outdoor (I/O) ratio were also analyzed to investigate the actual condition of indoor air quality and effect of outdoor PM on indoor PM. As a result, the correlation between indoor and outdoor PM in elementary school was more significant in PM2.5 and PM1 than PM10. In the case of I/O ratio, the I/O ratio of PM10 was higher than that of 1 in four elementary schools except SD (BB:2.21, NS: 1.67, IS: 1.73, SI: 1.17). This indicates that the activity of students has a great effect on the concentration of indoor PM10.

• Journal of the Korea Society of Computer and Information
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• v.26 no.4
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• pp.119-131
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• 2021

In this study, I compared the pattern design method of classic shirts focused on the men's clothing consturction textbook. It was intended to select a shirt pattern drawing method suitable for men in their 20s by conducing a appearance evaluation with a 3D simulation program. Pattern drawing method, sizes, appearance evaluation, garment pressure. were evaluated, and SPSS 26.0 program was used for analysis. According to the Pattern drawing method, there were differences in application sizes, and there were many parts where designated sizes were applied. The shirt pattern is mostly the same for the front chest and back chest, front waist and back waist. However, if there is a front and back difference of the chest and the waist circumference, the fit was considered better. B pattern was evaluated as the best in appearance evaluation, color distribution, and mesh condition through 3D simulation, and B pattern was analyzed as the most suitable method for men in their 20s. Since this study applied the average sizes of the 7th Korean Human Body Dimension Survey report in 20s, it is thought that caution should be paid to apply them to all 20s. In the future, it is also thought that research on the actual fit and patterns of various body types and materials in their 20s should be carried out.

• Journal of Industrial Convergence
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• v.20 no.9
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• pp.99-107
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• 2022

This study was conducted to empirically analyze the effect of life behavior and socio-environmental satisfaction on life satisfaction of the elderly with or without hearing loss. To this end, 3,071 elderly people of 「the Survey on the Actual Condition of the Elderly」 in 2020 were set as the subjects. After controlling for their demographic variables, the multiple regression model showed that the elderly with hearing loss had different factors of life behavior and socio-environment satisfaction that affected their life satisfaction compared to those without. As a result, the sub-factors of life behavior in the elderly with hearing loss, such as economic activities, social group activities, the use of the center, and the sub-factors of social environment satisfaction, such as family satisfaction and environmental satisfaction, had a positive (+) effect on life satisfaction. Especially, the elderly with hearing loss had more limitations in both the area of living behavior and the area of social environment satisfaction than the elderly without hearing loss. Therefore, in order to improve the life satisfaction of the elderly with hearing loss, it is suggested that the government and local governments should simultaneously supplement welfare policies and facilities for the elderly with hearing loss.

• Computers and Concrete
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• v.31 no.4
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• pp.337-348
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• 2023

Shear wall is commonly used as a lateral force resisting system of concrete mid-rise and high-rise buildings, but it brings challenges in providing relatively large space throughout the building height. For this reason, the structure system where the upper structure with bearing, non-bearing and/or shear walls that sits on top of a transfer plate system supported by widely spaced columns at the lower stories is preferred in some regions, particularly in low to moderate seismic regions in Asia. A thick reinforced concrete (RC) plate has often been used as a transfer system, along with RC transfer girders; however, the RC plate becomes very thick for tall buildings. Applying the post-tensioning (PT) technique to RC plates can effectively reduce the thickness and reinforcement as an economical design method. Currently, a simplified model is used for numerical modeling of PT transfer plate, which does not consider the interaction of the plate and the upper structure. To observe the actual behavior of PT transfer plate under seismic loads, it is necessary to model whole parts of the structure and tendons to precisely include the interaction and the secondary effect of PT tendons in the results. This research evaluated the seismic behavior of shear wall-type residential buildings with PT transfer plates for the condition that PT tendons are included or excluded in the modeling. Three-dimensional finite element models were developed, which includes prestressing tendon elements, and response spectrum analyses were carried out to evaluate seismic forces. Two buildings with flat-shape and L-shape plans were considered, and design forces of shear walls and transfer columns for a system with and without PT tendons were compared. The results showed that, in some cases, excluding PT tendons from the model leads to an unrealistic estimation of the demands for shear walls sit on transfer plate and transfer columns due to excluding the secondary effect of PT tendons. Based on the results, generally, the secondary effect reduces shear force demand and axial-flexural demands of transfer columns but increases the shear force demand of shear walls. The results of this study suggested that, in addition to the effect of PT on the resistance of transfer plate, it is necessary to include PT tendons in the modeling to consider its effect on force demand.

• Korean Chemical Engineering Research
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• v.62 no.1
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• pp.27-35
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• 2024

Fuel gases such as methane and propane are used in explosion hazardous area of domestic plants and can form non-uniform mixtures with the influence of process conditions due to leakage. The fire-explosion risk assessment using literature data measured under uniform mixtures, damage prediction can be obtained the different results from actual explosion accidents by gas leaks. An explosion characteristics such as explosion pressure and flame velocity of non-uniform gas mixtures with concentration change similar to that of facility leak were examined. The experiments were conducted in a closed 0.82 m long stainless steel duct with observation recorded by color high speed camera and piezo pressure sensor. Also we proposed the quantification method of non-uniform mixtures from a regression analysis model on the change of concentration difference with time in explosion duct. For the non-uniform condition of this study, the area of flame surface enlarged with increasing the concentration non-uniform in the flame propagation of methane and was similar to the wrinkled flame structure existing in a turbulent flame. The time to peak pressure of methane decreased as the non-uniform increased and the explosion pressure increased with increasing the non-uniform. The ranges of K_G (Deflagration index) of methane with the concentration non-uniform were 1.30 to 1.58 [MPa·m/s] and the increase rate of K_G was 17.7% in methane with changing from uniform to non-uniform.

• Journal of the Korean GEO-environmental Society
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• v.15 no.1
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• pp.63-68
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• 2014

In this study, it was found that determined the photocatalytic degradation of antibiotics (lincomycin, LM) with various catalyst composite of titanium dioxide ($TiO_2$), hydroxyapatite (HAP) and germanium (Ge) under UV-A irradiation. At first, various type of complex catalysts were investigated to compare the enhanced photocatalytic potential. It was observed that in order to obtain the removal efficiencies were $TiO_2/HAP/Ge$ > $TiO_2/Ge$ > $TiO_2/HAP$. The composition of $TiO_2/HAP/Ge$ using a statistical approach based on mixture analysis design, one of response surface method was investigated. The independent variables of $TiO_2$ ($X_1$), HAP ($X_2$) and Ge ($X_3$) which consisted of 6 condition in each variables was set up to determine the effects on LM ($Y_1$) and TOC ($Y_2$) degradation. Regression analysis on analysis of variance (ANOVA) showed significant p-value (p < 0.05) and high coefficients for determination value ($R^2$ of $Y_1=99.28%$ and $R^2$ of $Y_2=98.91%$). Contour plot and response curve showed that the effects of $TiO_2/HAP/Ge$ composition for LM degradation under UV-A irradiation. And the estimated optimal composition for TOC removal ($Y_2$) were $X_1=0.6913$, $X_2=0.2313$ and $X_3=0.0756$ by coded value. By comparison with actual applications, the experimental results were found to be in good agreement with the model's predictions, with mean results for LM and TOC removal of 99.2% and 49.3%, respectively.

• Journal of the Korean Society of Radiology
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• v.8 no.7
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• pp.467-477
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• 2014

The purpose of this study is to offer data base for establishment of dental training x-ray generator based safety usage through surveying real radiation safety management state of radiation worker's in plan of operations that have dental training x-ray generators and use it. For it, comprehensive references were surveyed referring reports of current state of regulation technique development and domestic radiation safety evaluation and nuclear related legislation regarding radiation safety management of dental training x-ray generators. On the basis of it, questionnaires were filled in about respondent's general characteristic radiation safety manager's status current state of radiation safety management and the level of knowledge & consciousness. For the study, the survey was conducted to 224 people of radiation safety managers and university graduates training assistants and full-time professors who can treat dental training x-ray generators in education center. through this survey 95 questionnaires were used as analysis materials except the insufficient and omitted responses. As a method of analysis, the frequency and percentage were figured out with the general characteristics and safety manager's status. Chi-square test for frequency and correlation per question analysis and Pearson correlation analysis for crosslevel correlation were done with current state of radiation safety management and knowledge & consciousness level. As a result, running dental training x-ray generators was dealt with by 20's to 40's who have high education level over post undergraduate degree and major in dental hygienic. In addition, female have higher consciousness level for radiation safety management than male. It shows significal linear relation statistically(${\chi}^2$ >5, 0.1${\chi}^2$ >5, 0.3${\chi}^2$ >5, 0.3

• Journal of Intelligence and Information Systems
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• v.22 no.2
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• pp.33-56
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• 2016

Many researchers have focused on developing bankruptcy prediction models using modeling techniques, such as statistical methods including multiple discriminant analysis (MDA) and logit analysis or artificial intelligence techniques containing artificial neural networks (ANN), decision trees, and support vector machines (SVM), to secure enhanced performance. Most of the bankruptcy prediction models in academic studies have used financial ratios as main input variables. The bankruptcy of firms is associated with firm's financial states and the external economic situation. However, the inclusion of qualitative information, such as the economic atmosphere, has not been actively discussed despite the fact that exploiting only financial ratios has some drawbacks. Accounting information, such as financial ratios, is based on past data, and it is usually determined one year before bankruptcy. Thus, a time lag exists between the point of closing financial statements and the point of credit evaluation. In addition, financial ratios do not contain environmental factors, such as external economic situations. Therefore, using only financial ratios may be insufficient in constructing a bankruptcy prediction model, because they essentially reflect past corporate internal accounting information while neglecting recent information. Thus, qualitative information must be added to the conventional bankruptcy prediction model to supplement accounting information. Due to the lack of an analytic mechanism for obtaining and processing qualitative information from various information sources, previous studies have only used qualitative information. However, recently, big data analytics, such as text mining techniques, have been drawing much attention in academia and industry, with an increasing amount of unstructured text data available on the web. A few previous studies have sought to adopt big data analytics in business prediction modeling. Nevertheless, the use of qualitative information on the web for business prediction modeling is still deemed to be in the primary stage, restricted to limited applications, such as stock prediction and movie revenue prediction applications. Thus, it is necessary to apply big data analytics techniques, such as text mining, to various business prediction problems, including credit risk evaluation. Analytic methods are required for processing qualitative information represented in unstructured text form due to the complexity of managing and processing unstructured text data. This study proposes a bankruptcy prediction model for Korean small- and medium-sized construction firms using both quantitative information, such as financial ratios, and qualitative information acquired from economic news articles. The performance of the proposed method depends on how well information types are transformed from qualitative into quantitative information that is suitable for incorporating into the bankruptcy prediction model. We employ big data analytics techniques, especially text mining, as a mechanism for processing qualitative information. The sentiment index is provided at the industry level by extracting from a large amount of text data to quantify the external economic atmosphere represented in the media. The proposed method involves keyword-based sentiment analysis using a domain-specific sentiment lexicon to extract sentiment from economic news articles. The generated sentiment lexicon is designed to represent sentiment for the construction business by considering the relationship between the occurring term and the actual situation with respect to the economic condition of the industry rather than the inherent semantics of the term. The experimental results proved that incorporating qualitative information based on big data analytics into the traditional bankruptcy prediction model based on accounting information is effective for enhancing the predictive performance. The sentiment variable extracted from economic news articles had an impact on corporate bankruptcy. In particular, a negative sentiment variable improved the accuracy of corporate bankruptcy prediction because the corporate bankruptcy of construction firms is sensitive to poor economic conditions. The bankruptcy prediction model using qualitative information based on big data analytics contributes to the field, in that it reflects not only relatively recent information but also environmental factors, such as external economic conditions.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.1
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• pp.51-57
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• 2014

Purpose: The present study was conducted to establish the experimental condition for the proper evaluation of protein removal efficacy when developing protein removal agents. Its protein removal efficacy was further analyzed and compared with the result from protein removal efficacy against protein deposition on contact lens to suggest the evaluation method for efficacy of protein removal agents. Methods: Protein digestibility assay presented in the Korean pharmacopoeia was selected to establish the evaluation method for efficacy of papain, pancreatin, subtilisin A and protease itself as a ingredient and protein removal tablets or solution containing those enzymes and find a suitable test conditions. Furthermore, the cleaning efficacy of commercially available protein removal tablets and solution on balafilcon A lens deposited with protein artificially was measured and the correlation between two evaluation methods was further analyzed. Results: When pancreatin itself and the product containing pancreatin was evaluated by protein digestibility assay, both reached 28 IU/mg, the standard value of protein digestibility suggested by the Korean pharmacopoeia. In case of protease and subtilisin A tested with trichloroacetic acid B solution, both of them met the enzyme activity level proposed by the manufacturers when they were evaluated by protein digestibility assay however, papain and subtilisin A tested with trichloroacetic acid A solution were not reached the enzyme activity level. Among protein removal agents, three products except a product containing pancreatin did not meet the enzyme activity value specified by the manufacturer when they were evaluated by protein digestibility assay. However, actual protein removal efficacy of three products except a papain-containing product on the lens was greater than 90% protein removal. In the case of papain-containing protein removal product, its effect was not measured by protein digestibility assay however, its actual protein removal efficacy on the lens reached 73.72%. Conclusions: From the results, it was confirmed that the efficacy of protein removal agents for contact lens should be evaluated by different method according to the type of proteolytic enzyme contained. That is, the protein removal agents containing pancreatin, protease and subtilisin A can be evaluated by protein digestibility assay and protein removal efficiency evaluation and the products containing papain can be effectively evaluated by only the evaluation method for protein removal efficiency employing the lens.