• 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.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.5
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• pp.491-503
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• 2014

In this paper, a $TM_{31}$ higher order mode half circular-ring microstrip antenna with monopole-like radiation characteristic for on-body communication is proposed. By using shorting vias, $TM_{31}$ resonance mode was excited, while achieving compact low-profile antenna with monopole-like radiation characteristics. To overcome the narrow bandwidth of a patch antenna, a C-shape half ring patch with shorting vias having $TM_{31}$ mode is closely located around a half circular patch. For size reduction, half mode is adopted. The proposed antenna has the overall dimensions of $0.25{\lambda}_0{\times}0.46{\lambda}_0{\times}0.025{\lambda}_0$ at the industrial, scientific, and medical(ISM) 2.45 GHz band(2.4~2.485 GHz) and the 10-dB return loss is 4.24 % ranging from 2.38 to 2.49 GHz. To verify body effect, two-thirds muscle equivalent semi solid phantom was fabricated and used to measure the antenna performance. A communication link is analysed to investigate the effect of human-body movements and antenna locations.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.15 no.6
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• pp.71-79
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• 2016

Evaluation of the walkability of the urban pedestrian network requires construction of a pedestrian network model that reflects Space Syntax Theory. Space Syntax Theory deduces an integration value through which materials for evaluation of the pedestrian network's connectivity can be produced; and can aid in illustrating the ease of walkability through the model's calculation of pedestrian indices such as movability, comfort, and safety. But the representation of space syntax theory in the pedestrian network requires that turn delay be added by means of a network-type construction method. While tree-based Dial Algorithm proposed for the logit-based probability walkability distribution model may be effective for link-based pedestrian volume distribution, it requires further network expansion to reflect turn delays. In this research, Vine-based Dial Algorithm is executed in order to obtain a measure reflecting the integration value for Space Syntax Theory. The Vine-based Dial Algorithm of two adjacent links, which forms the minimum unit of the Vine network, has the advantage of encompassing turn delay, and thus eliminates the need for network expansion. Usage of the model to evaluation of complicated pedestrian spheres such as urban roads is left to further research. Especially the progression of the proposed method is deduced through case study.

• Journal of Intelligence and Information Systems
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• v.22 no.3
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• pp.1-21
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• 2016

IT-based subjective well-being (SWB) services, a main part of wellness IT, should measure the SWB state of individuals in an unrestrained, cost-effective manner. The dictionaries for sentiment analysis available in the market may be useful for this purpose, but obtaining proper sentiment values using only words from the sentiment lexicon is impossible; therefore, a new dictionary including wellness vocabulary is needed. The existing sentiment dictionaries link only a single sentiment value to a single sentiment word, although sentiment values may vary depending on personal traits. In this study, we develop an extended version of the SenticNet sentiment dictionary dubbed WellnessWordNet. SenticNet is considered the best and most expressive among the already existing sentiment dictionaries. Using the information provided by SenticNet, we created a database including the wellness states (estimated values) of stress, depression, and anger to develop the WellnessWordNet system. The accuracy of the system was validated through actual tests with live subjects. This study is unique and unprecedented in that i) an extended sentiment dictionary, WellnessWordNet, is developed; ii) values for wellness state language are offered; and iii) different sentiment values, namely contextual polarity, for people of the same gender or age group are suggested.

• Korean Security Journal
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• no.36
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• pp.201-225
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• 2013

The link between transnational environmental harm and national security has attracted new attention due to the environmental crisis such as climate change, nuclear accidents and, pollution. However, both domestic and international environmental regimes are still tied to the unsuccessful and unclear notion-sustainable development. The present author argues that environment should be considered as a security matter for the effective environmental protection. If, for example, a nation committed a serious environmental harm and the effects spans borderlines, and the source nation refuses to cooperate or compensate, would sustainable development still be an appropriate measure? Then, what would be the victim state's tool to protect its own security? The present author first looks into the possibility utilizing UN Security Council. But due to its limited legality and effectiveness in this environmental matter the present author would like to propose a non-traditional but a not-brand new method. This new method reflects two new trends both from international law and security areas. First, this approach clearly moves from the military focused security concept to broader security concept. Second, this is also a shift from traditional international law to transnational law. With these two new approaches, we will find a more suitable answer both for securing national environmental security and for protecting environment.

• The Korean Journal of Pharmacology
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• v.32 no.3
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• pp.433-444
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• 1996

We describe a novel approach to evaluate quantitatively the amounts of denatured proteins in cells upon heat exposure. A thiol compound, diamide [azodicarboxylic acid bis (dimethylamide)] causes protein cross-linking with exposed sulfyhydryl residues of denatured proteins. Since denatured proteins expose normally well-hidden sulfhydryl groups, these will be preferentially cross-linked by diamide. Thus diamide acts to 'trap' denatured proteins. We observed that protein aggregates (high molecular weight protein aggregates, HMA) appeared on SDS-polyacrylamide gels run under non-reducing conditions and that the amount of HMA can be quantified by scanning the gels using a gas flow counter. Heating cells followed by a fixed dose of diamide exposure resulted in HMA increases in a heat-dose dependent manner, demonstrating that the quantitation of HMA could serve as a measure of heat-denatured proteins. We compared thermotolerant and nontolerant cells and found decreased HMA in tolerant cells upon heat treatment. As an attempt to examine the kinetics of protein renaturation (or 'repair'), we measured the amounts of aggregates formed by the addition of diamide at various times after heat shock. Such experiments demonstrate an equally rapid disappearance of HMA in previously unheated and in thermotolerant cells. Levels of HMA in tolerant cells increased significantly after electroporation of HSP70 specific mAbs, suggesting an involvement of HSP70 in reducing HMA levels in thermotolerant cells upon heat exposure. Immunoprecipitation studies using anti-HSP70 antibody indicated an association of HSP70 with heat-denatured proteins. Our results suggest that heat induces protein denaturation, and that elevated level of HSP70 present in thermotolerant cells protects them by reducing the level of protein denaturation rather than by facilitating the 'repair' (or degradation) process.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.1
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• pp.311-320
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• 2018

This study was conducted to investigate the relationship among major satisfaction (MS), clinical competence (CC), career decision-making self-efficacy (CDMS), and career decision level (CDL) for undergraduate nursing students. A self-report instrument was used to measure MS, CC, CDMS, and CDL. Questionnaires were completed by 307 nursing students in three nursing colleges, and path analysis was employed to validate the proposed model and analyze the causal relationships among variables. Four constructs (MS, CC, CDMS, and career decision) were analyzed. To build a path model, MS and CC were linked to CDMS and career decision. The initial analysis suggested that the modification needed modification; therefore, a covariance link was added. The overall goodness of fit for indices indicated satisfactory path analysis. The indices were revealed as $x^2=2412$, GFI=0.996, AGFI=0.961, and RMSEA=0.068. As a result, the proposed model was acceptable with a good fit, and there were significant direct and indirect effects of paths in the model. Specifically, MS and CC had a direct influence on CDMS, and MS and CDMS directly affected CDL. Moreover, MS and CC had indirect effects on CDL through CDMS. These results imply that students' CDMS should be seriously considered when designing counseling programs for career guidance, and substantiality of CC education is needed to improve CDMS. These results may provide a practical guideline to provide educational intervention for nursing students.

• Journal of Distribution Science
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• v.13 no.11
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• pp.101-109
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• 2015

Purpose - A traditional retail market is a place that offers economic opportunity to employees and employers alike it also is a place where the community can meet. The Korean government has invested three trillion won to improve physical and non-physical aspects in traditional retail markets since 2004. However, little research on this has been conducted. We explore this research gap that could lead to theory extension. We analyze consumption behavior with respect to traditional retail markets through an empirical analysis, thus overcoming limits in previous research. We empirically analyze policy effects of traditional retail market projects supported by the Korean government. Research design, data, and methodology - We propose a traditional retail market improvement plan via the relation between cause and effect resulting from the analysis. More specifically, logit analysis was carried out with 1,754 consumers in 16 cities nationwide. In order to analyze consumer consumption behaviors nationwide, the probability was analyzed using a logit model. This research analyzes the link between support and non-support by the Korean government using binary values. The dependent variable is whether Korean government support is implemented; the binomial logistic regression is used as the statistical estimation technique. The object variables are:1 (support) or 0 (nonsupport), and the prediction value is between 1 and 0. As a result of the factor analysis of questions related to attributes of service quality, four factors were extracted: convenience, product, facilities, and service. Results - The results indicate that convenience, product, and facilities have a significant influence on consumer satisfaction in accordance with the government's traditional retail market support. Additionally, the results reveal that convenience, product, facilities, and service all have a significant influence on consumer satisfaction in a traditional retail market's service quality and consumer satisfaction. Finally, the analysis indicates that the highly satisfied traditional retail market customer has a significant influence on revisit intention. Moreover, the results reveal that the highly satisfied traditional retail market customer has a significant influence on recommendation intention. Conclusions - This research focused on consumers nationwide to measure policy effects of traditional retail markets compared to previous research that focused on one traditional retail market or a specific area. We verified the relationship of service quality and customer satisfaction and consumer behavior based on service quality theory. The results indicate that consumer satisfaction of traditional retail markets supported by service quality factors has a significant impact. In a concrete form, the results indicate that these effects are from facility modernization projects and marketing support projects of the Korean government. The results also imply that these facility and management support effects from the Korean government have been consistent. We realize that the Korean government has to selectively support traditional retail markets in major cities and small and medium-sized cities. To that end, the Korean government needs to select a concentration strategy for the revitalization of traditional retail markets.

• The Journal of Korean Society for School & Community Health Education
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• v.1 no.1
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• pp.61-82
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• 2000

The purpose of this study was to find out the general problems of school food service and to explore a way to improve it, by examining elementary school teacher's consciousness and attitude toward it that gave a big impact on children's development of food habit. For attaining the purpose, the following research questions were posed : 1) What's elementary school teacher attitude toward school food service management? 2) What's elementary school teacher attitude toward school food service effect on children? 3) What's elementary school teacher opinion about how to develop school food service? The subjects of study were 328 male or female teachers who served at elementary school in urban and rural area, including eup, myon, or farming and fishing villages, Kyonggi province. A questionnaire survey was conducted over them. The conclusions were as follows: 1) Teacher Attitude Toward School Food Service Management Concerning food service place, the subjects were more satisfied at food service room(73.3%) than at classroom(23.0%). They responded that food service room was more effective, than classroom, for food transportation, distribution and post-arrangement. Their satisfaction at food service place was significantly different. The older teachers considered personnel management and cooking room's sanitary management to be more efficient, and their age made a significant difference to their consciousness of these things. Many teachers(63.1%) thought the measures to prevent and manage group food poisoning were relatively efficient. The male teachers expressed more affirmative view on the efficiency of school food expense management and menu preparation than female teachers, and there was a significant disparity between male and female teachers. 2) Elementary School Food Service Effect School food service was thought to be very effective for physical growth(74.1%) and physical strength improvement(70.1%). Teachers at smaller school revealed more affirmative response toward school food service effect on correcting an unbalanced diet, and older teachers considered its effect on nutrition knowledge acquisition and learning outcome to be more great. Teachers at larger school put less value on its effect on table manners, and school size produced a significant difference. The number of teachers who thought school food service generally raised parent concern and support for school(36.6%) was a little more than that of teachers who didn't think so(15.2%). And the number of teachers who didn't consider its effect on improving parent food life to be good(29.3%) was slightly more than that of teachers who did. 3) School Food Service Reform Measure What's most urgently needed for better school food service management appeared to be an expansion of facilities concerned, followed by more effective food distribution and transport, cooking room's better sanitary management, more successful food poisoning prevention and management, more effective food expense management, and an increase of food service personnel in the order named. The most effective means of school food service education was found to be a creation of link system to family, followed by a development of school food service education program, a development of teaching materials, an insertion of school food service in curriculum, and teacher education in the order named.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.9 no.6
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• pp.43-53
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• 2010

The increasing interest in the use of automated photographic equipment in Korea enables to detect speed violation and enforce traffic laws. Since 1996, Korean National Police Agency has been promoting a project for installation of Automated Speed Enforcement (ASE) system aiming at reduction of accidents. Recently, point to point speed cameras operate to measure a driver's average speed across length of road and/or the spot speed at individual camera sites along the road length. In this study, we were analyzed to driver's operating characteristics in point to point speed cameras. The point to point speed camera system has link-long influence on drivers and their speeds despite enforcement being visible only at the start and end of enforced road length. Then, mean and 85th percentile speeds were below speed limit along enforced road length by the two camers. Also, Female drivers were driving at low speed than male drivers along the road length.