• Journal of Intelligence and Information Systems
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• v.18 no.3
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• pp.119-135
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• 2012

Among various recommendation techniques, neighborhood-based Collaborative Filtering (CF) techniques have been one of the most widely used and best performing techniques in literature and industry. This paper proposes new approaches that can enhance the neighborhood-based CF techniques by identifying a few best neighbors (the most similar users to a target user) more accurately with more information about neighbors. The proposed approaches put more weights to the users who have more items co-rated by the target user in similarity computation, which can help to better understand the preferences of neighbors and eventually improve the recommendation quality. Experiments using movie rating data empirically demonstrate simultaneous improvements in both recommendation accuracy and diversity. In addition to the typical single rating setting, the proposed approaches can be applied to the multi-criteria rating setting where users can provide more information about their preferences, resulting in further improvements in recommendation quality. We finally introduce a single metric that measures the balance between accuracy and diversity and discuss potential avenues for future work.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.1
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• pp.195-199
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• 2011

There are many causes for the variation of the result in oral proficiency test such as the examiner, the task, the theme of the interview, and the gender of the participants. Previous literature documents that the rater is an important variable influencing test scores of second language oral proficiency. Although much research in language testing has been conducted concerning rater effect on test scores, there has been little attention paid to the effect of potential rater variables in language testing on their rating process. There are noticeably different contents of the rating scales across different speaking tests developed in different context. Therefore, it would not be appropriate to apply the same rating criteria for various tasks. In conclusion, we need more subject protocol analyses and more thoughtful studies on rating processes. In other words, the oral proficiency test needs a more realistic and valid tool for the assessment of second language proficiency.

• The Journal of the Korea Contents Association
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• v.16 no.11
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• pp.731-741
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• 2016

It has become five years since comprehensive programming licenses were rendered in Korea. Allocating a lion's share of their air time on live news and news commentaries, those channels have established a unique live production system or a broadcasting system which is heavily live production-oriented, to be exact. The live commentaries are filled with a mixture of news flashes, conventional news commentaries, and debates. Those channels get their news and commentary programs made through subsidiaries' where production directors and studio staffs belong. They, being very sensitive about viewer rating, tend to be aggressive about reruns of highly rated programs and they do not even seem to care when the regular programs actually went out. This kind of reckless strategy to pursue a higher viewer rating could limit not only new programming attempts but also exposure diversity.

• Korean Journal of Child Studies
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• v.26 no.4
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• pp.293-302
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• 2005

This study investigated behavior characteristics for the gifted(N=210) and the high achievers(N=1l5). The participations in this study were 200 teachers who rated their 325 students' behavior characteristics in 25 public elementary schools in U.S.A rating of behavior characteristics in learning style, motivation, creativity, and leaderships by teachers indicated differences in keen observation, rapid insight into cause-effect relationship, a large storehouse of information, language fluency, absorption/task persistent, preference for own learning activities, concerns for moral/ethical issues, and a diversity of interests between groups. No differences in understanding of underlying principles, organization, curiosity, creativeness, motivation, initiating activities in areas of personal interest, directing group activities, and intellectual playfulness/imagination were found in addition to some differences between two groups.

• Asia pacific journal of information systems
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• v.23 no.4
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• pp.85-102
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• 2013

This study proposes a web presence readiness model based on pre-payment service functions and a post-payment service function both of which embrace the major concerns of customers in the online purchasing context. Based on the concept of customer utility from the product itself and instrumental utility, the research model suggests four antecedents including, Perceived Economic Benefits, Product Search Support Quality, e-Shopping Method Diversity, and Post-Payment Support Quality. We empirically examined a proposed research model using data collected from online rating company websites. Among the four antecedents, post payment support quality is found to be the most influential determinant of customer evaluation on e-commerce websites. Based on the empirical results, the current study proposes an alternate model of web presence readiness. The findings of this study may provide an insight to field practitioners designing commercial websites. The implications and future research directions are further discussed.

• Textile Coloration and Finishing
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• v.33 no.4
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• pp.191-201
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• 2021

In this study, an eco-friendly indigo reduction system(scale up reduction, use of buffer solution, and pH control) using baker's yeast(Saccharomyces cerevisiae) was applied for natural indigo(Polygonum tinctorium) dyeing of Hanji fabric and Hanji-mixture fabric(Hanji/Cotton, Hanji/Silk). The effect of concentration of baker's yeast, repeat dyeing, and bath reuse was investigated in terms of dye uptake indicating reduction power. And the oxidation-reduction potential(ORP) was monitored. We also evaluated color properties and colorfastness according to the color strength. The yeast concentration did not significantly affect the maximum reduction power. However, the highest yeast concentration was effective in improving the initial dye uptake, and its the reduction retention power was the most excellent. Even on the last reduction day, the effect of increasing the dye uptake by repeat dyeing was observed. And it was confirmed that the reduction bath could be reused for up to 30 days by supplementing yeast at the end of reduction. For all the fabrics used, deeper and darker PB color were obtained by repeat dyeing. As dyeing was repeated, purplish tint got stronger on the Hanji/Silk fabric compared to other fabrics. Regardless of the composition of Hanji fabrics and color strength, washing and dry cleaning fastness were relatively good with above rating 4-5, and fastness to rubbing and light were acceptable with a rating 3-4 ~ 4-5. The eco-friendly natural indigo dyeing process using niram and baker's yeast would offer global marketability and diversity of Hanji product as a sustainable high value-added material.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.10
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• pp.5120-5142
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• 2018

Social media enables customers to share their views, opinions and experiences as product reviews. These product reviews facilitate customers in buying quality products. Due to the significance of online reviews, fake reviews, commonly known as spam reviews are generated to mislead the potential customers in decision-making. To cater this issue, review spam detection has become an active research area. Existing studies carried out for review spam detection have exploited feature engineering approach; however limited number of features are considered. This paper proposes a Feature-Centric Model for Review Spam Detection (FMRSD) to detect spam reviews. The proposed model examines a wide range of feature sets including ratings, sentiments, content, and users. The experimentation reveals that the proposed technique outperforms the baseline and provides better results.

• Journal of the Ergonomics Society of Korea
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• v.26 no.4
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• pp.57-64
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• 2007

In the world, the old population is growing fast and many countries went into an advanced age society. Therefore the development of everyday products, electric appliances, and welfare services considering old people is more important than ever. In particular, the complexity of products can cause many problems for old people. Universal design is an approach to create environments and products that recognizes the diversity of users, regardless of their ability or age. Universality evaluation for a product is very important to verify old people's accessibility and usability for the product. Universality means how good a product was designed in view of universal design principles. In this study, UNIX, a method to evaluate the universality of a product was developed. UNIX was based on seven universal design principles; equitable use, flexibility in use, simple and intuitive, perceptible information, tolerance for error, low physical effort, size and space for approach and use. UNIX is a kind of expert evaluation and very simple method. The method is consisted of two steps. In the first step, relative weights for seven principles and subjective ratings on design suitability for each principle are obtained. In the second step, universality index (UNIX) of each product is obtained by weighted average multiplying relative weights and rating scores. As a case study, this method was applied for mouse designs. In conclusion, this method could be effectively applied to evaluate the universality of a product.

• Korean Journal of Health Education and Promotion
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• v.30 no.2
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• pp.41-53
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• 2013

Objectives: As the size of elderly population living alone grows, socioeconomic diversity has also increased. This study examined if social risk factors of poor self-rated health were distinguishable between the low income elderly and their non-low income counterparts both living alone. Methods: The '2006 Elderly Health Interview Survey' conducted by D-gu in Seoul was utilized. We divided the elderly living alone into two groups depending on their economic status: low income and non-low income. Employing logistic regression, we analyzed the associations of poor self-rated health with socio-demographic factors, health-related factors, social support, the relations with children, social activities, welfare service use, and the perception of neighborhood safety. Results: Proportion of rating one's own health being poor was different between two populations. Social support was important for the self-rated health of the non-low income elderly, while welfare service use, the perception of neighborhood safety, and the relations with children were noticeable for the low income elderly. Conclusions: To better understand the health need of elderly population living alone, their heterogeneity in socioeconomic characteristics should be taken into account.

• Journal of the Korean Society of Food Culture
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• v.10 no.4
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• pp.269-279
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• 1995

The purpose of this study was to examine the relationships of nutritional and social factors among 100 children aged $5{\sim}6$ years. Forty five children (45%) were selected from families with low socioeconomic status, while 55 children (55%) were from those with high socioeconomic status. Cognitive performance of the children was measured by the Draw a man test and the degrees of hyperactivity were assessed by both children's mothers and their teachers using two different Check List (Behavior check list and Conner's rating scale). There were few associations between cognitive performance and nutritional variables. However, levels of hyperactivity were related positively to diversity of food intake and weight percentage for age, and negatively to animal and processed food preferences. These results indicate a possible role of nutrition on psychological development.