• Journal of Applied Reliability
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• v.12 no.3
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• pp.131-138
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• 2012

A design of reliability qualification test based on performance distribution is developed. In general, the performance of an item degrades as the time goes by and the failure of an item occurs when the performance degradation reaches the pre-determined critical level. This article considers the reliability qualification test based on a more tightened critical value at the earlier stage to reduce the evaluation testing time and cost. A numerical example is provided to illustrate how to use the developed reliability qualification test.

• Proceeding of Spring/Autumn Annual Conference of KHA
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• 2008.11a
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• pp.458-463
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• 2008

This study focused on the suggestion that is improved alternation with relation to construction item & assurance term in order to deal with the assurance conflict efficiently which have been happened in the apartment housing. To correspond to this purpose of research, as a first step, we introduced the add item & sub item of construction work on the basis upon construction specifications of the number of 17 on housing law as a alternation of the defects assurance construction item that is necessary to correct as soon as possible. As a second step of the research, we did cross analysis & compare the result of defects happened to the apartment housing complex of 293 with the defect' rate of construction work excepted from the supervisory item, and main performance estimation items in the HPGS(House Performance Grading System), and analysis results introduced from question survey. As the result of this research work, we became to reflect the improving schemes on the housing Law the year of 2007.

• The Mathematical Education
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• v.43 no.2
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• pp.151-162
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• 2004

For the past several years, performance assessment has been widely used by mathematics teachers. The superiority of performance assessment items compare to multiple choice items has been discussed by many researchers, however these discussions tend to be lack of empirical data. Thus, this study aims to examine the effectiveness of tree response items in comparison with multiple choice items. Using the information function in Item Response Theory(IRT), item information of free response items and multiple choice items from the Third International Mathematics and Science Study-Repeat(TIMSS-R) were obtained and compared. Test informations of the whole mathematics area as well as each content area of mathematics were computed. On average, tree response items yielded more information than multiple choice items, especially in measurement and data interpretation. This study also revealed that free response items estimated students' mathematics ability more accurately than multiple choice items with smaller number of items.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.13 no.12
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• pp.5826-5841
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• 2019

In our previous research, we proposed a tag emotion-based item recommendation scheme. The ternary associations among users, items, and tags are described as a three-order tensor in order to capture the emotions in tags. The candidates for recommendation are created based on the latent semantics derived by a high-order singular value decomposition technique (HOSVD). However, the tensor is very sparse because the number of tagged items is smaller than the amount of all items. The previous research do not consider the previous behaviors of users and items. To mitigate the problems, in this paper, the item-based collaborative filtering scheme is used to build an extended data. We also apply the probabilistic ranking algorithm considering the user and item profiles to improve the recommendation performance. The proposed method is evaluated based on Movielens dataset, and the results show that our approach improves the performance compared to other methods.

• Journal of Intelligence and Information Systems
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• v.18 no.4
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• pp.1-17
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• 2012

Personalized smart devices such as smartphones and smart pads are widely used. Unlike traditional feature phones, theses smart devices allow users to choose a variety of functions, which support not only daily experiences but also business operations. Actually, there exist a huge number of applications accessible by smart device users in online and mobile application markets. Users can choose apps that fit their own tastes and needs, which is impossible for conventional phone users. With the increase in app demand, the tastes and needs of app users are becoming more diverse. To meet these requirements, numerous apps with diverse functions are being released on the market, which leads to fierce competition. Unlike offline markets, online markets have a limitation in that purchasing decisions should be made without experiencing the items. Therefore, online customers rely more on item-related information that can be seen on the item page in which online markets commonly provide details about each item. Customers can feel confident about the quality of an item through the online information and decide whether to purchase it. The same is true of online app markets. To win the sales competition against other apps that perform similar functions, app developers need to focus on writing app descriptions to attract the attention of customers. If we can measure the effect of app descriptions on sales without regard to the app's price and quality, app descriptions that facilitate the sale of apps can be identified. This study intends to provide such a quantitative result for app developers who want to promote the sales of their apps. For this purpose, we collected app details including the descriptions written in Korean from one of the largest app markets in Korea, and then extracted keywords from the descriptions. Next, the impact of the keywords on sales performance was measured through our econometric model. Through this analysis, we were able to analyze the impact of each keyword itself, apart from that of the design or quality. The keywords, comprised of the attribute and evaluation of each app, are extracted by a morpheme analyzer. Our model with the keywords as its input variables was established to analyze their impact on sales performance. A regression analysis was conducted for each category in which apps are included. This analysis was required because we found the keywords, which are emphasized in app descriptions, different category-by-category. The analysis conducted not only for free apps but also for paid apps showed which keywords have more impact on sales performance for each type of app. In the analysis of paid apps in the education category, keywords such as 'search+easy' and 'words+abundant' showed higher effectiveness. In the same category, free apps whose keywords emphasize the quality of apps showed higher sales performance. One interesting fact is that keywords describing not only the app but also the need for the app have asignificant impact. Language learning apps, regardless of whether they are sold free or paid, showed higher sales performance by including the keywords 'foreign language study+important'. This result shows that motivation for the purchase affected sales. While item reviews are widely researched in online markets, item descriptions are not very actively studied. In the case of the mobile app markets, newly introduced apps may not have many item reviews because of the low quantity sold. In such cases, item descriptions can be regarded more important when customers make a decision about purchasing items. This study is the first trial to quantitatively analyze the relationship between an item description and its impact on sales performance. The results show that our research framework successfully provides a list of the most effective sales key terms with the estimates of their effectiveness. Although this study is performed for a specified type of item (i.e., mobile apps), our model can be applied to almost all of the items traded in online markets.

• The Journal of Korean Academy of Sensory Integration
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• v.2 no.1
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• pp.11-19
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• 2004

Objective : This study is to provide the norms of normal children when comparing the performance ability of preschool children while using the kinesthesia test of Sensory Integration and Praxis Tests(SIPT). Methods : Participants consisted of 90 normal children ranging in age from four to six years. The kinesthesia test of SIPT was utilized to investigate the performance ability. Results : 1. Regarding the kinesthesia ability according to age, the average value of kinesthesia performance error decreased as age getting older and that value showed the statistically significant differences between four and five, six age(p<0.05). 2. The kinesthesia performance ability according to gender, the accuracy of both hands and the dominant hand did not show the statistically significant differences. 3. Regarding the kinesthesia performance ability of test items, 1R item and 6R item(26.2cm), 5R item and 2L item(20.2cm) passing through the midline of body and having the large movement in distance and angle showed the difficulty to perform in all the children between 4 and 6 age. Conclusion : By providing the norms of the kinesthesia performance ability in normal children of the above results to the occupational therapists treating children, the helpful data to the hand skill development of children, exercise plan and implementation, and the performance therapy of ADL through the proper evaluation and training of kinesthesia is considered for the occupational therapists to be provided.

• Journal of information and communication convergence engineering
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• v.17 no.2
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• pp.135-141
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• 2019

Collaborative filtering algorithms often encounter data sparsity issues. To overcome this issue, auxiliary information of relevant items is analyzed and an item attribute matrix is derived. In this study, we combine the user-item attribute preference with the traditional similarity calculation method to develop an improved similarity calculation approach and use weights to control the importance of these two elements. A collaborative filtering algorithm based on user-item attribute preference is proposed. The experimental results show that the performance of the recommender system is the most optimal when the weight of traditional similarity is equal to that of user-item attribute preference similarity. Although the rating-matrix is sparse, better recommendation results can be obtained by adding a suitable proportion of user-item attribute preference similarity. Moreover, the mean absolute error of the proposed approach is less than that of two traditional collaborative filtering algorithms.

• KIEAE Journal
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• v.11 no.6
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• pp.29-35
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• 2011

This study aims to suggest improvement plans and explain about the current situation for facilitating Long-life housing, based on the results on flexibility items among 27 items consisting the "Housing Performance Grading System". From the 9th of January, 2006 to the month of July in 2011, study has analyzed evaluation results on 216 different types for each grade and reviewed evaluation criteria and methods. Current evaluation criteria applies quantitative analysis, by calculating in percentage how much bearing walls and columns, which hinder flexibility, take up space in the household. The evaluation rate for each household was assessed in relation to its structural system, and a higher grade was given to column-typed structures. In addition, to facilitate long-life housing, this study extracted harmful factors, expanding the range of evaluation. The first step was to evaluate structure, which is the basic element. The second step can to evaluate the probability of applying resources in response to the changes of structural systems. As The third step, Flexibility item will evaluate the probability of moving the water-using area, suggesting gradual approach. Thus, through evaluations of flexibility items, the study aims to improve the quality of life in household, by avoiding uniform structures and acquiring more freedom for space designs.

• Journal of the Korean Society for Railway
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• v.13 no.3
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• pp.327-332
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• 2010

In this paper we presents an approach to assessing the efficiency of freight railroad stations reflecting freight item importance weights with multiple performance indicators and multiple operational condition indicators. We evaluate 187 freight railroad stations using data envelopment analysis with assurance region. Each freight item's loading/unloading volume is used as a performance indicator. Freight labor and yard capacity are used as operational condition indicators. Freight item importance weights are reflected to the data envelopment analysis as assurance region. The evaluation results facilitates the organization's decision making by providing valuable information.

• Journal of Science Education
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• v.38 no.1
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• pp.168-181
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• 2014

The purpose of this study was to monitor evaluation in science education at primary and secondary school in Korea. In order to do this, the survey was administered. The subject was 518 teachers; 292 elementary school teachers, 110 middle school science teachers and 116 general high school science teachers. It was found that the ratio of paper examination increased while that of performance evaluation decreased according to the grade of school. In the science paper examination, the ratio of selection type item was higher than that of supply type item, and the ratio of item belonging to knowledge area was higher than that of item belonging to the inquiry area regardless of the grade of school, teaching career, and teacher's gender. The teachers recognized the necessity of supply type item, but they suffered from the reliability of the result of that item. And it was hard for them to do performance evaluation because it took much time and effort. This study suggested that the high-quality in-service teacher training be provided and laboratory assistants who help the science experiment and grading test papers be employed in order to fulfil the performance evaluation and increase the ratio of supply type item and items belonging to the inquiry area.