• Journal of the Korean Institute of Educational Facilities
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• v.16 no.1
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• pp.43-50
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• 2009

This research is to analyze LCC of Heat Pump system in university building by reduction of electric power costs for education and incentive system for gas. Produced details item different expense of EHP and GHP equipment construction step and preservation administration step. Analysis result is as following. 1) Executed LCC analysis for target system after lowering whole curriculum reduction of electric power costs for education. Analysis result, energy cost-cutting effect of EHP appears greatly than GHP unlike existent study finding, EHP decided by economical system. 2) Sensitivity analysis executed by incentive 500,000 won per units and geometrical ration of gas expense by 1%. As a result, because lowering effect of electric charges appears greatly, EHP decided by more economical system than GHP. As research result of front is different from existent study finding, EHP by lowering of electric charges for alteration and education of governmental frequent volunteer system was decided by more economical system than GHP.

• Educational Technology International
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• v.24 no.2
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• pp.331-358
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• 2023

This paper explores the impact of mobile device usage frequency in the classroom on students' perceptions of their use. To assess this, we created a survey that measured students' perceived frequency, usefulness, and convenience of using mobile devices, using a reversed Technology Acceptance Model. Through the analysis of responses from 781 Korean students, utilizing confirmatory item factor analyses and a structural equation mixture model, we found that the effect of frequent mobile device use on students' positive perceptions is non-linear. As the frequency reaches to a certain level, the effect sizes of the frequency in the positive perceptions diminishes. Additionally, students who used mobile devices less frequently in class reported higher levels of difficulties in using the devices. This study introduces a tool for evaluating multiple aspects of students' perceptions regarding mobile device use and offers a framework for understanding the relationship between usage frequency, usefulness, and convenience.

• Korean Journal of Cognitive Science
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• v.32 no.3
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• pp.117-139
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• 2021

The way of change detection in which presence of a different item is determined between memory and test arrays with a brief in-between time interval resembles how visual search is done considering that the different item is searched upon the onset of a test array being compared against the items in memory. According to the resemblance, the present study examined whether varying the probability of change occurrence in a visual short-term memory-based change detection task can influence the aspect of response-decision making (i.e., change prevalence effect). The simple-feature change detection task in the study consisted of a set of four colored boxes followed by another set of four colored boxes between which the participants determined presence or absence of a color change from one box to the other. The change prevalence was varied to 20, 50, or 80% in terms of change occurrences in total trials, and their change detection errors, detection sensitivity, and their subsequent RTs were analyzed. The analyses revealed that as the change prevalence increased, false alarms became more frequent while misses became less frequent, along with delayed correct-rejection responses. The observed change prevalence effect looks very similar to the target prevalence effect varying according to probability of target occurrence in visual search tasks, indicating that the background principles deriving these two effects may resemble each other.

• Journal of Software Assessment and Valuation
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• v.16 no.1
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• pp.81-88
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• 2020

Various methods of differentiating and servicing digital content for individual users have been studied. Searching for association rules is a very useful way to discover individual preferences in digital content services. The Apriori algorithm is useful as an association rule extractor using frequent itemsets. However, the Apriori algorithm is not suitable for application to an actual content service because it considers only the reference count of each content. In this paper, we propose a new algorithm based on the Apriori that searches association rules by using purchase history and usage-time for each item. The proposed algorithm utilizes the usage time with the weight value according to purchase items. Thus, it is possible to extract the exact preference of the actual user. We implement the proposed algorithm and verify the performance through the actual data presented in the actual content service system.

• The Korean Journal of Pain
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• v.25 no.3
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• pp.161-167
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• 2012

Background: Neck and shoulder pain (NSP) is fairly common in adolescents, which is associated with a high prevalence of NSP found during adulthood as well; therefore, its significance during adolescence should not be underestimated. We surveyed the prevalence of recurrent NSP, lifestyle, and risk factors in Korean high school students, and examined the influence of recurrent NSP on the quality of life. Methods: Nine hundred thirty one male students (16-19 years old) from two academic high schools in Seoul were included in this study. The survey consisted of a questionnaire to assess the prevalence of recurrent NSP, with questions regarding having an occurrence more than once a week, characteristics of NSP, activity and lifestyle of the students, and the risk factors for recurrent NSP. A 36-item Short Form questionnaire was also examined. Results: We found that 44.3% of the high school students surveyed had recurrent NSP (more than once a week) and the overall prevalence of NSP was 79.1%. The average sitting time was $10.2{\pm}2.7$ h/day. 59.0% did not sit straight, 14.7% used assisting devices during reading, and 11.9% answered that they stretched regularly. Found from their self assessed health, frequent fatigue and frequent depressed mood presented significant associations with the higher prevalence of recurrent NSP. Conclusions: Korean high school students had a high prevalence of recurrent NSP. Clinical attention is needed for the prevention and resolution of recurrent NSP found in high school students.

• Journal of Preventive Medicine and Public Health
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• v.43 no.6
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• pp.486-495
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• 2010

Objectives: The effect of meat consumption on cardiometabolic risk has been continuously studied, but their associations are not conclusive. The aim of this study is to examine the association between the consumption of meat or red meat and carotid intima-media thickness (IMT) in healthy Korean adults. Methods: This study evaluated 2374 community-dwelling adults (933 men and 1441 women) who were free of cardiovascular disease or cancer, living in a rural area in Korea. Total meat and red meat intakes were assessed with a validated 103 item-food frequency questionnaire. Carotid IMT was evaluated ultrasonographically, IMTmax was defined as the highest value among IMT of bilateral common carotid arteries. Results: After adjustment for potential confounding factors, the mean IMTmax tended to increase in higher meat consumption groups in both men and women with metabolic syndrome (p for trend= 0.027 and 0.049, respectively), but not in participants without metabolic syndrome. Frequent meat consumption (${\geq}5$ servings/week) was significantly associated with higher IMTmax in men with metabolic syndrome (by 0.08 mm, p=0.015). Whereas, the association was not significant in women (by 0.05 mm, p=0.115). Similar but attenuated findings were shown with red meat intake. Conclusions: Our findings suggest that a higher meat consumption may be associated with a higher carotid IMT in Korean adults with metabolic syndrome. The frequent meat consumption (${\geq}5$ servings/week), compared with the others, was associated with a higher carotid IMTmax only in men with metabolic syndrome. Further research is required to explore optimal meat consumption in people with specific medical conditions.

• The KIPS Transactions:PartD
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• v.13D no.6 s.109
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• pp.765-774
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• 2006

An association rule discovery, a technique to analyze the stored data in databases to discover potential information, has been a popular topic in stream data system. Most of the previous researches are concerned to single stream data. However, this approach may ignore in mining to multidimensional stream data. In this paper, we study the techniques discovering the association rules to multidimensional stream data. And we propose a AR-MS method reflecting the characteristics of stream data since make the summarization information by one data scan and discovering the association rules for significant rare data that appear infrequently in the database but are highly associated with specific event. Also, AR-MS method can discover the maximal frequent item of multidimensional stream data by using the summarization information. Through analysis and experiments, we show that AR-MS method is superior to other previous methods.

• Journal of the Korea Society of Computer and Information
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• v.17 no.2
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• pp.197-206
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• 2012

A exisiting recommedation system using association rules has the problem, such as delay of processing speed from a cause of frequent scanning a large data, scalability and accuracy as well. In this paper, using a Implicit method which is not used user's profile for rating, we propose the personalized recommendation system which is a new method using the FP-tree mining based on RFM. It is necessary for us to keep the analysis of RFM method and FP-tree mining to be able to reflect attributes of customers and items based on the whole customers' data and purchased data in order to find the items with high purchasability. The proposed makes frequent items and creates association rule by using the FP-tree mining based on RFM without occurrence of candidate set. We can recommend the items with efficiency, are used to generate the recommendable item according to the basic threshold for association rules with support, confidence and lift. To estimate the performance, the proposed system is compared with existing system. As a result, it can be improved and evaluated according to the criteria of logicality through the experiment with dataset, collected in a cosmetic internet shopping mall.

• Journal of the Korean Society for Library and Information Science
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• v.52 no.3
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• pp.289-334
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• 2018

Even though information in many languages other than English is quickly increasing, English is still playing the role of the lingua franca and being accounted for the largest proportion on the web. Therefore, it is necessary to investigate the key features and differences between "information searching behavior using mother tongue as a search language" and "information searching behavior using English as a search language" of users who are non-mother tongue speakers of English to acquire more diverse and abundant information. This study conducted the experiment on the web searching which is applied in concurrent think-aloud method to examine the information searching behavior and the cognitive process in Korean search and English search through the twenty-four undergraduate students at a private university in South Korea. Based on the qualitative data, this study applied the frequency analysis to web search pattern under search language. As a result, it is active, aggressive and independent information searching behavior in Korean search, while information searching behavior in English search is passive, submissive and dependent. In Korean search, the main features are the query formulation by extract and combine the terms from various sources such as users, tasks and system, the search range adjustment in diverse level, the smooth filtering of the item selection in search engine results pages, the exploration and comparison of many items and the browsing of the overall contents of web pages. Whereas, in English search, the main features are the query formulation by the terms principally extracted from task, the search range adjustment in limitative level, the item selection by rely on the relevance between the items such as categories or links, the repetitive exploring on same item, the browsing of partial contents of web pages and the frequent use of language support tools like dictionaries or translators.

• Journal of the Korean Society of Costume
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• v.59 no.7
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• pp.17-33
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• 2009

The purpose of this study was to get some pieces of prior information to eventually develop high value-added fashion cultural products design using local cultural resources, to promote the cultural tourism festival. For this purpose, this study is carried out the investigation of cultural product stores and visitors' questionnaire survey. The subjects of this study were festivals which were selected as cultural tourism festival by the Ministry of Culture, Sports and Tourism from 2000 to 2008. Of them, six festivals were finally selected but food festival was excluded. The results of this study were as follows; First, the store survey was conduced to analyze the situation of the products of cultural tourism festival. The most frequent product was accessories. And a T-shirt was found to be sold every festival probably because it was the most popular item and basic item which people could buy without burden. While the most diverse kinds of products were found in the Andong, the Jinju and Gangjin were found not to develop various products. In the design motif used for cultural products, most products did not use festival or local image. The highest use of the festival and local image was found in Gangjin and Muju. The Andong and Chungju were found to sell very common products buying anywhere rather than products using local cultural resources or image. In the material of cultural products, most products use metal. And In the price of cultural products, 10,000-30,000 won was found highest. Second, the purchase conditions of cultural tourism festival visitors were examined. The visiting goal and companion of visitors was found to vary with the type of cultural tourism festival. The types of visitors were also found to have an effect on the choice of items in the purchase of cultural products sold in the festival. Only one third of respondents responded buying one and more cultural products. The purchase rate was found high in the festival where cultural product items were various and there were many products symbolizing festival or region. The most purchased item was a mobile phone hanger and the amount of purchasing cultural products was 10,000-30,000 won. The reason not to purchase cultural products was dissatisfaction with utility, originality, possibility of a present, symbolism, and price. The most important attribute in the purchase of cultural products was design, followed by symbolism, price, originality, and innovation. The highly preferred product group included clothing, miscellaneous goods, and accessories. Specifically, T-shirt was found highest. Based on these research results, it was found that the design strategy for the cultural products development should consider both regional and festival images. The items and designs of the cultural products should reflect visitors' characteristics and the price zone should be varied.