• Journal of the Korean earth science society
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• v.26 no.3
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• pp.283-296
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• 2005

The effect of ozone and surface temperature on the ozone band at $9.7{\mu}m$ has been investigated from radiative transfer theory together with observations in order to derive empirical methods for remotely sensing ground-ozone concentration. Simultaneous observations of satellite (MODIS Aqua; ECT 13:30) and ground-ozone at 79 stations have been used over the Seoul Metropolitan Area (SMA; 125.7-127.2 E, 37.2-37.7 N) during four ozone-warning days in the year 2003. Cloud effect on the band in the methods was filtered out based on synoptic observations. Upwelling radiance values at $9.6{\mu}m$ which have been estimated at the given ozone concentration of 327-391 DU depend on surface temperature (Ts) showing $5.52\~5.78Wm^{-2}sr^{-1}\;at\;Ts = 290 K,\;and\;9.00\~9.57Wm^{-2}sr^{-1}$ Ts = 325K. Thus, the partitioned contributions of ozone and temperature to intensity of ozone absorption band are $0.26Wm^{-1}sr^{-1}/64\;DU\;and\;0.31 Wm^{-2}sr^{-1}/35K$, respectively. Here the intensity which has been used to remotely detect ground-ozone concentration from infrared satellite measurement is defined as the difference in brightness temperature between $11{\mu} m\;and\;9.7{\mu}m (i.e.,\; T_{11-9.7})$. The methods in this study have been applied to estimate ground-ozone from MODIS data in cases that there are significant correlations between the band intensity and ground-ozone. The values of estimated ozone significantly correlate (0.49-0.63) with ground observations at a significance level of $1\%$. For the improved methods, further study may be required to use tropospheric ozone rather than ground-ozone, considering the variation stratospheric ozone.

• Journal of the Korean earth science society
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• v.32 no.3
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• pp.276-293
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• 2011

In this study a modeling system consisting of Weather Research and Forecasting (WRF), Sparse Matrix Operator Kernel Emissions (SMOKE), the Community Multiscale Air Quality (CMAQ) model, and the CMAQ-Model of Aerosol Dynamics, Reaction, Ionization, and Dissolution (MADRID) model has been applied to estimate enhancements of $PM_{10}$ during Asian dust events in Korea. In particular, 5 experimental formulas were applied to the WRF-SMOKE-CMAQ (MADRID) model to estimate Asian dust emissions from source locations for major Asian dust events in China and Mongolia: the US Environmental Protection Agency (EPA) model, the Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model, and the Dust Entrainment and Deposition (DEAD) model, as well as formulas by Park and In (2003), and Wang et al. (2000). According to the weather map, backward trajectory and satellite image analyses, Asian dust is generated by a strong downwind associated with the upper trough from a stagnation wave due to development of the upper jet stream, and transport of Asian dust to Korea shows up behind a surface front related to the cut-off low (known as comma type cloud) in satellite images. In the WRF-SMOKE-CMAQ modeling to estimate the PM10 concentration, Wang et al.'s experimental formula was depicted well in the temporal and spatial distribution of Asian dusts, and the GOCART model was low in mean bias errors and root mean square errors. Also, in the vertical profile analysis of Asian dusts using Wang et al's experimental formula, strong Asian dust with a concentration of more than $800\;{\mu}g/m^3$ for the period of March 31 to April 1, 2007 was transported under the boundary layer (about 1 km high), and weak Asian dust with a concentration of less than $400\;{\mu}g/m^3$ for the period of 16-17 March 2009 was transported above the boundary layer (about 1-3 km high). Furthermore, the difference between the CMAQ model and the CMAQ-MADRID model for the period of March 31 to April 1, 2007, in terms of PM10 concentration, was seen to be large in the East Asia area: the CMAQ-MADRID model showed the concentration to be about $25\;{\mu}g/m^3$ higher than the CMAQ model. In addition, the $PM_{10}$ concentration removed by the cloud liquid phase mechanism within the CMAQ-MADRID model was shown in the maximum $15\;{\mu}g/m^3$ in the Eastern Asia area.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.11 no.6
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• pp.111-122
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• 2016

Support and efforts are being strengthened at the national level for entrepreneurial activities that are expected to revitalize our economy. Generally, according to the previous studies, it is known that entrepreneurship positively affects economic growth and the reduction of unemployment rate through employment creation. The analysis of the impact of entrepreneurial activities on economic growth and job creation is mainly based on national comparative analysis. In this paper, however, the impact of start-up activities in the Busan metropolitan city on regional economic growth and employment improvement. In this study, the dummy variables were assigned to firms within three years, five years, and ten years after start-up according to the period since the start-up of the firm. As a result of the empirical analysis, the value of dummy variable of the start - up firms was found to be significant in the analysis of the sales growth rate as the dependent variable according to the preceding study by Evans(1987). Therefore, it can be seen that the growth rate of the start - up company is higher than that of the other companies and it is positive for the regional economic growth. In addition, the coefficient of the dummy variable decreases from the enterprise analysis to the latter within three years, five years, and ten years after the start-up, and confirms that the coefficient of the firm's start-up years has a negative value. I could see more clearly. On the other hand, in the analysis of the effect of start-up firms on unemployment rate reduction, the growth rate of regular workers was higher than that of other firms. This suggests that it positively affects the reduction of the unemployment rate in the region. In addition, in the dynamic analysis using the Almon estimation formula and the Koyck model, the effect of log-transformed net start-up firms on the growth rate of new workers is very significant. As a result of the above model, It is reaffirmed that start-up activity has a positive effect on employment growth.

• Asia pacific journal of information systems
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• v.22 no.4
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• pp.75-99
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• 2012

Innovation can come from inside or outside organizations. Recently, organizations have begun turning to external knowledge more often, through various forms of collective intelligence (CI) as collaborative platform to solve complex problems. Several factors facilitate this CI utilization phenomenon. First, with the rapid development of Internet and social media, numerous web applications have become available to millions of the Internet users over the past few decades. Web 2.0 and social media have become innovative web applications that provide an environment for human social interaction and collaboration. Second, the diffusion of simple and easy-to-use technologies that enable users to interact and design web applications without programming skills have led to vast, previously unknown amounts of user-generated content. Finally, the Internet has enabled communities to connect and collaborate, creating a virtual world of CI. In this study, web enabled CI is defined as a composed ability of individuals who are acting as a single cognitive unit to achieve common goals, think reasonably, solve problems, make decisions, carry out complex tasks, and develop creative ideas collectively through participation and collaboration on the web. Although CI plays a critical role in organizational innovation and collaboration, the dubious quality of CI is still problem that is difficult to solve. In general, the quality level of content collected from the crowd is lower than that from professionals. Thus, it is important to identify determinants of CI quality and to analyze the relationship between CI quality and its usefulness. However, there is a lack of empirical study on the quality factors of web-enabled CI. There exist a variety of web enabled CI sites such as Threadless, iStockphoto or InnoCentive, Wikipedia, and Youtube. One of the most successful forms of web-enabled CI is the Wikipedia online encyclopedia, accessible all over the world. Another one example is Naver KnowledgeiN, a typical and popular CI site offering question and answer (Q&A) services. It is necessary to study whether or not different types of CI have a different effect on CI quality and its usefulness. Thus, the purpose of this paper is to answer to following research questions: ${\bullet}$ What determinants are important to CI quality? ${\bullet}$ What is the relationship between CI quality factors and the usefulness of web-enabled CI? ${\bullet}$ Does CI type have a moderating effect on the relationship between CI quality, its determinants, and CI usefulness? Online survey using Google Docs with email and Kakao Talk was conducted for collecting data from Wikipedia and Naver KnowledgeiN users. A totoal of 490 valid responses were collected, where users of Wikipedia were 220 while users of Naver KnowledgeiN were 270. Expertise of contributors, community size, and diversity of contributors were identified as core determinants of perceived CI quality. Perceived CI quality has significantly influenced perceived CI usefulness from a user's perspective. For improving CI quality, it is believed that organizations should ensure proper crowd size, facilitate CI contributors' diversity and attract as many expert contributors as possible. Hypotheses that CI type plays a role of moderator were partially supported. First, the relationship between expertise of contributors and perceived CI quality was different according to CI type. The expertise of contributors played a more important role in CI quality in the case of Q&A services such as Knowledge iN compared to wiki services such as Wikipedia. This implies that Q&A service requires more expertise and experiences in particular areas rather than the case of Wiki service to improve service quality. Second, the relationship between community size and perceived CI quality was different according to CI type. The community size has a greater effect on CI quality in case of Wiki service than that of Q&A service. The number of contributors in Wikipeda is important because Wiki is an encyclopedia service which is edited and revised repeatedly from many contributors while the answer given in Naver Knowledge iN can not be corrected by others. Finally, CI quality has a greater effect on its usefulness in case of Wiki service rather than Q&A service. In this paper, we suggested implications for practitioners and theorists. Organizations offering services based on collective intelligence try to improve expertise of contributeros, to increase the number of contributors, and to facilitate participation of various contributors.

• Asia pacific journal of information systems
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• v.19 no.2
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• pp.95-116
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• 2009

Increasingly the institutional theory has been an important theoretical view of decision making process and IT adoption in many academic researches. This study used the institutional theory as a lens through which we can understand the factors that enable the effective appropriation of advanced information technology. It posits that mimetic, coercive, and normative pressures existing in an institutionalized environment could influence the participation of top managers or decision makers and the involvement of users toward an effective use of IT in their tasks. Since the introduction of IT, organizational members have been using IT in their daily tasks, creating and recreating rules and resources according to their own methods and needs. That is to say, the adaptation process of the IT and outcomes are different among organizations. The previous studies on a diverse use of IT refer to the appropriation of technology from the social technology view. Users appropriate IT through not only technology itself, but also in terms of how they use it or how they make the social practice in their use of it. In this study, the concepts of institutional pressure, appropriation, participation of decision makers, and involvement of users toward the appropriation are explored in the context of the appropriation of the mobile electronic medical record system (M-EMRS) in particularly a hospital setting. Based on the conceptual definition of institutional pressure, participation and involvement, operational measures are reconstructed. Furthermore, the concept of appropriation is measured in the aspect of three sub-constructs-consensus on appropriation, faithful appropriation, and attitude of use. Grounded in the relevant theories to appropriation of IT, we developed a research framework in which the effects of institutional pressure, participation and involvement on the appropriation of IT are analyzed. Within this theoretical framework, we formulated several hypotheses. We developed a second order institutional pressure and appropriation construct. After establishing its validity and reliability, we tested the hypotheses with empirical data from 101 users in 3 hospitals which had adopted and used the M-EMRS. We examined the mediating effect of the participation of decision makers and the involvement of users on the appropriation and empirically validated their relationships. The results show that the mimetic, coercive, and normative institutional pressure has an effect on the participation of decision makers and the involvement of users in the appropriation of IT while the participation of decision makers and the involvement of users have an effect on the appropriation of IT. The results also suggest that the institutional pressure and the participation of decision makers influence the involvement of users toward an appropriation of IT. Our results emphasize the mediating effect of the institutional pressure on the appropriation of IT. Namely, the higher degree of the participation of decision makers and the involvement of users, the more effective appropriation users will represent. These results provide strong support for institutional-based variables as predictors of appropriation. These findings also indicate that organizations should focus on the role of participation of decision makers and the involvement of users for the purpose of effective appropriation, and these are the practical implications of our study. The theoretical contribution of this study is lies in the integrated model of the effect of institutional pressure on the appropriation of IT. The results are consistent with the institutional theory and support previous studies on adaptive structuration theory.

• 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.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.6
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• pp.155-165
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• 2015

The objective of this study is to verify the structural correlations among trust, satisfaction, commitment, relation-continuing intention for internet fashion shopping mall. The statistical significance of questionnaire survey data for 360 customers was verified by using SPSS 18.0 and AMOS 18.0 statistical programs with significance levels of the ${\alpha}=0.05$. First of all, Cronbach's ${\alpha}$ was also assessed to verify the reliability of the measuring tool, and the fitness of the model were also verified to investigate the fitness of this research model. Finally, structural equation model analysis was performed to verify the structural correlations among the structural correlations among trust, satisfaction, commitment, relation-continuing intention for internet fashion shopping mall. On the basis of the empirical analysis, the following key results were drawn. First, trust for internet fashion shopping mall has the positively significant effects on satisfaction. Second, trust for internet fashion shopping mall has the positively significant effects on commitment. Third, trust for internet fashion shopping mall has the positively significant effects on relation-continuing intention. Fourth, satisfaction for internet fashion shopping mall has the positively significant effects on relation-continuing intention. Fifth, commitment for internet fashion shopping mall has the positively significant effects on relation-continuing intention. Sixth, the path of trust${\rightarrow}$satisfaction${\rightarrow}$relation-continuing intention for internet fashion shopping mall has the significant indirect effects, therefore the mediation effect of satisfaction was significant. Seventh, the path of trust${\rightarrow}$commitment${\rightarrow}$relation-continuing intention for internet fashion shopping mall has the significant indirect effects, therefore the mediation effect of commitment was significant.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.13 no.4
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• pp.59-72
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• 2018

The purpose of this study is to investigate the factors affecting the intention to use healing farming by setting aged readiness, rural healing supply condition, and rural healing service as independent variables. This study has been started based on the idea that it is necessary to provide healing service through healing agriculture to the rapidly increasing elderly people and urban people who need mental rest. Therefore, the purpose of this study is to find out the various factors influencing intention to use healing agriculture through empirical analysis. Second, we want to examine whether the variables influenced the intention to use more. Third, based on the results of these tests, we suggest the policy for activation of healing agriculture by examining the factors necessary for the promotion of physical and mental health of the elderly in the aging society and the revitalization of healing agriculture for the mental healing of the urban people. For this study, a questionnaire survey was conducted for men and women over 30 years old, and the final 356 copies were analyzed. The validity of the research hypothesis was verified by linear regression analysis. The results of the analysis are as follows. First, the physical preparation, emotional preparation, and economic preparation of aged care preparations were found to have a significant effect on intention to use. Second, natural landscape, accessibility, and stability of rural healing supply conditions were found to have a significant effect on intention to use. But economics and expertise were dismissed. Third, crop cultivation, animal medication and healing facilities of rural healing service were proved to have significant influence on intention to use. In order to increase the utilization of healing agriculture, it is necessary for the consumer to be well prepared for aging. In rural healing supply conditions, accessibility and safety should be provided for healing facilities in rural healing services.And to increase the intention to use it.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.3
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• pp.159-174
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• 2020

This study is an empirical study analyzing the effects of positive psychological capital on job burnout. In addition, positive psychological capital played a role in organizational citizenship behavior, and tried to verify the role of organizational citizenship behavior as a black box, or parameter, between job burnout. And then, the sub-factors of organizational citizenship behavior were divided into two: individual-oriented organizational citizenship behavior and organization-oriented organizational citizenship behavior. To this end, a questionnaire survey was conducted for members of small and medium-sized enterprises to compare and analyze the relationship between variables. Positive psychological capital is increasing interest in that it can reduce the job burnout of members and embrace the propensity of young generations represented by millennials because it can improve the effectiveness by developing positive mental states and strengths of the organization. There is a need for research as a keyword. As a result of this study, first, it was found that positive psychological capital of SME(small and medium-sized enterprises) members had a positive effect on organizational citizenship behavior. Second, positive psychological capital was found to have a significant negative effect on job burnout. Third, it was a verification of how positive psychological capital and organizational citizenship behavior affect job burnout. In the relationship between positive psychological capital and job burnout, organization-oriented organizational citizenship behavior was found to play a mediating role. However, it was found that individual-oriented organizational citizenship behaviors among the organizational citizenship behaviors are not valid. In this study, positive psychological capital and job burnout, which have been mainly studied in service workers' emotional workers(crew, nurses, counselors, etc.), nursery teachers, and social workers, were applied to SME members by using the parameters of organizational citizenship behavior. You can put that implication on things. The positive psychological capital and organizational citizenship behavior can be further enhanced through SME members' love for the company, improvement of consideration among employees and resulting organizational commitment and work performance. It could also provide momentum for sustainable management for small and medium-sized enterprises that are relatively short of capital and resources.

• Korean Journal of Construction Engineering and Management
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• v.16 no.3
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• pp.36-48
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• 2015

To complete various types of finish works with higher quality in much less time, TACT, which was mostly used for high-rise buildings, has been adapted to meet the needs for systematic schedule management in construction sites. However, the effectiveness of adapting TACT has not been shown as expected due to the different perspectives on productivity from both general contractor and subcontractors based on unforeseen conditions according to the types of site. Furthermore, not enough theoretical backgrounds, empirical data, and systematic approaches to solve the fundamental problems caused by each participants' different views on productivity has produced obstacles for establishing effective solutions. Therefore, this research aims to analyze the possible main reasons for having different point of views regarding productivity among various participants of residential building sites using TACT based on literature review, site survey, and interviews. Also, case study was conducted to propose obtainable productivity (OP) regression equation and productivity achievement ratio (PAR) with reduction factors (RFs) and actual productivity (AP) data from an actual construction site. The proposed outcome may assist general contractors converting output management with PPC to productivity management with actual data using PAR. On the other hand, subcontractors would be able to estimate theory-based maximum productivity of construction sites with TACT by using OP. The PAR will enhance the communication between general and sub-contractors for their decision making process. Finally, the main RFs derived from PAR could be used as essential keys for productivity management to increase the economical and operational effectiveness of the construction project.