• Journal of Intelligence and Information Systems
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• v.27 no.1
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• pp.23-46
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• 2021

Collaborative filtering, which is often used in personalization recommendations, is recognized as a very useful technique to find similar customers and recommend products to them based on their purchase history. However, the traditional collaborative filtering technique has raised the question of having difficulty calculating the similarity for new customers or products due to the method of calculating similaritiesbased on direct connections and common features among customers. For this reason, a hybrid technique was designed to use content-based filtering techniques together. On the one hand, efforts have been made to solve these problems by applying the structural characteristics of social networks. This applies a method of indirectly calculating similarities through their similar customers placed between them. This means creating a customer's network based on purchasing data and calculating the similarity between the two based on the features of the network that indirectly connects the two customers within this network. Such similarity can be used as a measure to predict whether the target customer accepts recommendations. The centrality metrics of networks can be utilized for the calculation of these similarities. Different centrality metrics have important implications in that they may have different effects on recommended performance. In this study, furthermore, the effect of these centrality metrics on the performance of recommendation may vary depending on recommender algorithms. In addition, recommendation techniques using network analysis can be expected to contribute to increasing recommendation performance even if they apply not only to new customers or products but also to entire customers or products. By considering a customer's purchase of an item as a link generated between the customer and the item on the network, the prediction of user acceptance of recommendation is solved as a prediction of whether a new link will be created between them. As the classification models fit the purpose of solving the binary problem of whether the link is engaged or not, decision tree, k-nearest neighbors (KNN), logistic regression, artificial neural network, and support vector machine (SVM) are selected in the research. The data for performance evaluation used order data collected from an online shopping mall over four years and two months. Among them, the previous three years and eight months constitute social networks composed of and the experiment was conducted by organizing the data collected into the social network. The next four months' records were used to train and evaluate recommender models. Experiments with the centrality metrics applied to each model show that the recommendation acceptance rates of the centrality metrics are different for each algorithm at a meaningful level. In this work, we analyzed only four commonly used centrality metrics: degree centrality, betweenness centrality, closeness centrality, and eigenvector centrality. Eigenvector centrality records the lowest performance in all models except support vector machines. Closeness centrality and betweenness centrality show similar performance across all models. Degree centrality ranking moderate across overall models while betweenness centrality always ranking higher than degree centrality. Finally, closeness centrality is characterized by distinct differences in performance according to the model. It ranks first in logistic regression, artificial neural network, and decision tree withnumerically high performance. However, it only records very low rankings in support vector machine and K-neighborhood with low-performance levels. As the experiment results reveal, in a classification model, network centrality metrics over a subnetwork that connects the two nodes can effectively predict the connectivity between two nodes in a social network. Furthermore, each metric has a different performance depending on the classification model type. This result implies that choosing appropriate metrics for each algorithm can lead to achieving higher recommendation performance. In general, betweenness centrality can guarantee a high level of performance in any model. It would be possible to consider the introduction of proximity centrality to obtain higher performance for certain models.

• Quality Improvement in Health Care
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• v.3 no.2
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• pp.86-97
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• 1997

Background : It is a primary goal for hospital personnel to improve the quality of patient care. In Korea the concept of quality assurance has been spread over the last five years. Many hospitals have implemented quality assurance programs that fit their own philosophy and needs. As a result, they are supposed to have different experiences and attitudes toward quality assurance. To investigate their diversity will be helpful to have a direction to the future and to enhance the quality assurance activities in Korean hospitals. Objectives : The aim of this study is to obtain information about hospital personnel's attitude and opinion toward quality assurance in hospitals. Methods : A questionnaire was developed which consisted of five parts; the general characteristics of respondent, the concepts of quality assurance, need for quality assurance program, current status of quality improvement activities, and participation in programs. Using the registry of Korean hospitals, 102 hospitals with more than 400 beds were selected. Questionnaires were mailed to hospital staffs of each hospital; top managers, clinical department heads, registered nurses, medical recorders, and administrators. Results : Of 2038 questionnaires sent, 877 were returned, giving response rate of 44%. Most respondents(70%) regarded quality assurance as efforts to provide patient with care in highest quality and to improve effectiveness or resource utilization. Ninety-nine percent of respondents agreed to need for quality assurance in their hospitals. There were current quality improvement programs implemented in the department of 553 respondents(62%), and most of the(85%) have participated in at least one program. Lack of motivation was pointed out as a barrier to implement the programs. Conclusion : Although most respondents have known of the concept and need for quality assurance, this study suggests that education and motivation of hospital personnel be needed to activate the quality assurance programs in hospitals.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.16 no.4
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• pp.189-196
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• 2016

The purpose of this study is to investigate the causal relationships among self-efficacy, perceived usefulness, supervisor and peer support, satisfaction, and transfer intentions in the corporate mobile learning. For this study, the web survey was administered to 302 mobile learning learners of the A domestic corporation in South Korea. Structural equation modeling(SEM) analysis was conducted in order to examine the causal relationships among the variables. The results indicated that first, self-efficacy, perceived usefulness, and supervisor and peer support had positive effects on satisfaction. Second, supervisor and peer support and satisfaction had positive effects on transfer intentions. Third, satisfaction mediated the relationship between self-efficacy and perceived usefulness, while it did partially the relationship between supervisor and peer support and transfer intentions. Based on the result of the research, the study proposes organizational environment with cooperative supervisor and peer support should be made in order to improve the level of learners' transfer intentions. In addition, learning strategies that facilitate learners' self-efficacy and mobile information technology acceptance are needed to develop for enhancing the learners' satisfaction.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.9
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• pp.366-376
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• 2017

This study attempts to analyze the structure of the knowledge and duties of the vocational counseling service industry by using the text mining method and network analysis, which are methods of big data analysis. The subjects of the survey were vocational counseling, job placement and career change support, three fields in the unit elements of competence included in the National Competency Standards (NCS) which areproposed by the government. Although the analysis results of frequently used words showed that all three fields had independent duties, many were overlapping, such as counseling, examination, employment support, etc. for clients, job seekers, and others. The knowledge required by the employees of this field includes many new fields, such as start-up development, lifelong career consulting, job adaptation and culture conflict, besides the five subjects of vocational psychology, vocational counseling, labor market, job information, and law, which are included in the vocational counselor certification examination. Also, we suggested that the consultants adhere to emotional approaches, such as empathy, acceptance and attentiveness, and take a neutral stance. This study isvaluable in that it is the first attempt to objectively analyze the duties of the vocational counseling service field by big data analysis. In addition, it is also meaningful that we first confirmed the difference between the direction of government policy and the actual practice in the field.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.33 no.4
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• pp.77-86
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• 2015

The Koreanology as well as a study of the classics should start from the correct understanding of certain words or concepts. Inaccurate or even misinterpreted explanation is bound to lead to failure. If you read a classic text, if the object does not come up to indicate clearly what the bar often. Bout, are seen refer to the translation or commentary, sometimes encounter cases of very serious misunderstanding. If a simple mistake or error, and if you recognize and fix it, but eopget a big problem, described by early to conclude identified by the fact that the amount of problem becomes serious. Besides, if the trend will spread to quote it, the situation is not out of control. One sample is "Nodongchwibyeong(老松翠屛)" in "Kyoungdojapji(京都雜誌)" "Poonsock(風俗)" "Jetaek(第宅). In some places, it is called "Booyeon(附椽), it has been described elsewhere as a kind of "chwibyeong(翠屛)". This short manuscript clarified by reviewing the old literature closely, it was "songcheom", "songboong(松棚), another expression of Bungga(棚架). More precisely, it was a nickname of Hanyang Yangban in the 18th and 19th century. However, the historical research is just not as having a meaning only one explanation for the particular word. Dare to be confident that these study are meaningful. In the extremely weak division in the understanding of the original text, the cases of applying blindly without a reflection occurs frequently. This short manuscript is to give warning to recent trends. Humanities and classical field researchers made very carefully, taking into account the impact of translation and annotations, and the other branch to accommodate the research of classical humanities disciplines should try to see this information must be verified meets the facts.

• Korean journal of applied entomology
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• v.44 no.1 s.138
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• pp.73-90
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• 2005

Although the history of IPM can be traced back to the late 19th century, when ecology was identified as the foundation for scientific plant protection, it has been more than thirty years since first enunciation. Since than, the concept of IPM has evolved in multiple paths not only in entomology but in plant pathology and in weed science, and the philosophy has become a firm foundation to the science of plant protection. The IPM concept has gained wide general acceptance, however, because of the many-facet aspects, there has been some controversy and/or misunderstanding by the students and practitioners. In this paper, I was tried to review the concepts of IPM and to resolve the contradiction between the philosophy and practical techniques. On this line, the historical background and the concept of economic injury level, which is the foundation of the concepts, are reviewed and discussed the sampling techniques and the population dynamics of single pest, which were basic to the rational and effective application of the management techniques. IPM is not a science per se but it is a technique and it should be applicable to the real conditions. For this purpose, the information on the pests should be transferred to the producers as fast as possible. From such, some of my own opinion is presented in relation to current systems of the pest occurrence forecasting.

• Journal of Global Scholars of Marketing Science
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• v.10
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• pp.1-26
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• 2002

The present study examines the role of subjectively perceived factors of the attitude toward web shopping in forming an intention to use a web shopping intention. An integrative research model is presented and tested empirically. It includes the following three aspects of belief in Davis' TAM: perceived usefulness, perceived ease of use, perceived enjoyment. Specially, internet self-efficacy, or the belief in one's capabilities to organize and execute courses of Internet actions required to produce given attainments, is a potentially important factor in efforts to gain more favorable attitude toward web shopping close the digital divide that separates experienced Internet users from novices. Prior research on Internet self-efficacy has been limited to examining specific task performance and narrow behavioral domains rather than overall attainments in relation to general Internet use, and has not yielded evidence of reliability and construct validity. Survey data were collected to develop a reliable operational measure of Internet self-efficacy and to examine its construct validity. Also, much previous research has established that perceived ease of use is an important factor influencing user acceptance and usage behavior of information technologies. However, very little research has been conducted to understand how that perception forms and changes over time. The present study examines that higher internet self-efficacy is more getting favorable web shopping attitude, and web shopping intention as more as usefulness, enjoyment through the internet.

• Survey Research
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• v.8 no.1
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• pp.1-30
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• 2007

Several corporations are adopting the 6 Sigma program. Not all corporations are yielding intended results. The inconsistent results may due to the absence of an adequate strategy formulation of 6 Sigma implementation. The 6 Sigma is a qualify control program but its implications are not confined only to qualify improvement. The 6 Sigma program is a change program to bring about changes in organizations. The thesis focuses on developing an installation strategy or model of 6 Sigma program. The utility of the model developed in this research is supported by the empirical evidence. The validity of the model is tested and verified based on the questionnaire survey conducted at 281 business firms. Few research has adopted the empirical survey. The previous researches are mostly centered around identifying success factors. Unlike the present methodology adopted in this research, the past research methodologies are mainly case studies. The distinctive feature of this research does not confine only to the methodology. This research attempted to identify an installation model that would help enterprises get maximum output from the 6 Sigma program. The suggested model is named as Sequential Model(SM). The SM consists of three stages: the preparation stage, the acceptance stage, and the maturity stage. The model is based on the assumption that organizations should follow three stages sequentially to yield the desired output effectively, The preparation stage is further defined including the organizational change factor, the driving system factor, and the promotion factor. The result variable, the organizational performance, is also further defined including the market competitiveness, the employees competitiveness, and the financial performance. The Structural Equation Model was used to test the validity of the Sequential Model(SM). Several alternatives models were developed and compared. The test results consistently show that the suggested model is a valid one and proves its superiority over alternative models. Through this empirical research, we have shown that the strategies of enterprises in line with the proposed model gained better results over others. The research results would be useful information for enterprises that consider formulation of installation strategy of 6 Sigma program.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.12
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• pp.4752-4759
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• 2010

Using Technology Acceptance Model and flow theory as our foundation, this paper investigates the interrelationships among social influence, individual cognition, flow, and actual usage in the Web 2.0 environment. According to TAM, users evaluate perceived usefulness(PU) and ease of use(PEU) of information technology(IT) in accepting the innovative IT. Along with users' cognitive evaluation(i.e. PU and PEU), in case of UCC(user-created-contents), which is one of the representative Web 2.0 features, flow also has a significant effect on users' usage. Accordingly, the current study involve cognitive elements such as PU and PEU as well as flow of enjoyable state during using IT in exploring antecedents leading to UCC usage. On one hand, we consider the effect of social influence on users' cognition and flow toward actual usage because the more users creates Web contents, the more long-tail situation prevails on the Internet. Web 2.0 becomes a kind of social phenomena. The empirical results show that social influence affects positively both PU/PEU and flow. Users' cognitive evaluation and flow have positive impacts on users' UCC usage.

• The Journal of the Korea Contents Association
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• v.14 no.1
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• pp.223-237
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• 2014

The purpose of this study is to understand the perceptions of public officials in improving primary health care service for local communities by applying Q methodology that draw upon schematic model in subjectivity study. A survey was carried out among public officials at Gangneung Community Health Center, South Korea, to classify the 49 selected Q-statements into a normal distribution using a 11 point scale. The collected data was analyzed using QUANL program, and principal component factor analysis using varimax rotation was used to identify public officials' perceptions of improving quality of health care for local communities as a meaningful service provider. Type I can be categorized by a strong concern for the service acceptance, Type II can be categorized by advocating for service usability, Type III can be categorized by the pursuit of service specialization, Type IV can be categorized by roles for service accessibility, and Type V can be categorized by the suggestions for operation and management. The results provide information used to further improve quality of community health care service with the aim to promote the effectiveness of health care delivery and to increase health service utilization.