• Journal of Korean Society for Quality Management
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• v.11 no.1
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• pp.10-17
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• 1983

This paper studies item-life test plans with the specified item mean life $T_1$ (MTBF) - Producer's risk ${\alpha}$ and item mean life $T_2$ (MTBF, $T_2$ < $T_1$) - Consumer's risk ${\beta}$ when the probability of item survival follows the Weibull distribution (known shape parameter) as a expansion of [1]. And Operating Characteristic Curves and Average Life-testing Times of item-life test plans are computed for this paper and [1]. Cost analysis procedures are same as [1]. These results are computed by using computer program written in Level II Basic for Apple II Plus Micro-computer. Both this paper and [6] reduce the life-testing time for Weibull distribution in comparision with Exponential distribution, but results of [6] were computed for different criterions from this paper.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.4
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• pp.877-885
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• 2011

A collaborative filtering(CF) is the most widely used technique in recommender system. However, CF has sparsity and scalability problems. These problems reduce the accuracy of recommendation and extensive studies have been made to solve these problems, In this paper, we proposed a method that uses a weight so as to solve these problems. After creating a user-item matrix, the proposed method analyzes information about users who prefer the item only by using data with a rating over 4 for enhancing the accuracy in the recommendation. The proposed method uses information about the genre of the item as well as analyzed user information as a weight during the calculation of similarity, and it calculates prediction by using only data for which the similarity is over a threshold and uses the data as the rating value of unrated data. It is possible simultaneously to reduce sparsity and to improve accuracy by calculating prediction through an analysis of the characteristics of an item. Also, it is possible to conduct a quick classification based on the analyzed information once a new item and a user are registered. The experiment result indicated that the proposed method has been more enhanced the accuracy, compared to item based, genre based methods.

• Journal of Korea Society of Industrial Information Systems
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• v.20 no.5
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• pp.61-69
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• 2015

We are in overload status of information not just in a flood of information due to the data pouring from various kinds of mobile devices, online and Social Network Service(SNS) every day. While there are many existing information already created, lots of new information has been created from moment to moment. Linkage analysis has the shortcoming in that it is difficult to find the information we want since the number of rules increases geometrically as the number of item increases with the method of finding out frequent item set where the frequency of item is bigger than minimum support in this information. In this regard, this thesis proposes WT-algorithm that represents the transaction data set as Boolean variable item and grants weight to each item by making algorithm with Quine-McKluskey used to simplify the logical function. The proposed algorithm can improve efficiency of data mining by reducing the unnecessary rules due to the advantage of simplification regardless of number of items.

• Korean Medical Education Review
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• v.20 no.1
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• pp.20-31
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• 2018

Good assessment is crucial for feedback on curriculum and to motivate students to learn. This study was conducted to perform item analysis on the Medical Education Assessment Consortium clinical knowledge mock examination (MEAC CKME) (2011-2016) and to evaluate several effects to improve item quality using both classical test theory and item response theory. The estimated difficulty index (P) and discrimination index (D) were calculated according to each course, item type, A (single best answer)/R (extended matching) type, and grading of item quality. The cut-off values used to evaluate P were: >0.8 (easy); 0.6-0.8 (moderate); and <0.6 (difficult). The cut-off value for D was 0.3. The proportion of appropriate items was defined as those with P between 0.25-0.75 and D ${\geq}0.25$. Cronbach ${\alpha}$ was used to assess the reliability and was compared with those of the Korean Medical Licensing Examination (KMLE). The results showed the recent mean difficulty and decimation index was 0.62 and 0.20 for the first MEAC CKME and 0.71 and 0.19 for the second MEAC CKME, respectively. Higher grade items evaluated by a self-checklist system had better D values than lower grade items and higher grade items gradually increased. The preview and editing process by experts revealed maintained P, decreased recall items, increased appropriate items with better D values, and higher reliability. In conclusion, the MEAC CKME (2011-2016) is deemed appropriate as an assessment to evaluate students' competence and prepare year four medical students for the KMLE. In addition, the self-checklist system for writing good items was useful in improving item quality.

• Journal of Korean Clinical Health Science
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• v.8 no.2
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• pp.1426-1435
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• 2020

Objective: This study aims to develop CFT, a screening test for dementia that can be conducted on patients with mild cognitive impairment or early dementia. Methods: This study was conducted on therapists working at occupational therapy hospital in Gyeongsangnam-do. The data collection period is two months from July to September 2020, and the research participants were briefed on the purpose, significance, and anonymity of the research in consideration of ethical issues. A total of 33 copies of the data were finally analyzed, excluding those containing insufficient answers and errors, by distributing 40 copies of the data. SPSS Data Access pack 8.0 was used for data analysis, Cronbach's α value was evaluated for internal consistency reliability of each item, and Pearson Correlation coeffient between the lower scales of the assessment tool was measured. Results: The Cronbach's α value of the CFT was shown as .892 and the reliability of the assessment paper was shown to be quite high. The Cronbach's α value for each item in the cognitive assessment tool was the highest at .899 in the subtraction item, with exercise control (mook Chi Pa) at 888, visual memory, plus .887. The correlation of each item of cognitive assessment tools was found to be most correlated with the number of sustained concentrates and word2 to .934; in the stop word-numeric item and visual memory to be .85; and in the addition to the auditory memory item .739. Conclusion: Therefore, this study developed cognitive evaluation tools that can distinguish the diversity and cognitive level of screening tests and clarify standards, which are different from the existing dementia screening tools in Korea. Furthermore, the cognitive assessment tools of this study can be verified by applying them to patients with mild cognitive impairment and early dementia, and the criteria for generalization can be established.

• Korean Management Science Review
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• v.34 no.1
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• pp.71-84
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• 2017

The purpose of this study is to extract the characteristic cost through the time series analysis of each cost from 2003 to 2014, and to grasp the performance and relevance of the enterprise. Therefore, in this section, we analyzed the time-series analysis of selling, administrative, and non-operating expenses as described above. First, depreciation cost, advertising cost, transportation cost, research cost, current research cost, and ordinary development cost were extracted as the variables of interest to be verified in the empirical analysis. However, in the analysis of non-operating expenses, we could not extract the specific cost, but we could grasp the time-series flow of cost data before and after two epochs such as financial crisis and introduction of IFRS obligation. The results of this study show that sales management costs have a positive (+) effect on firm value. Empirical analysis confirms that management is trying to increase or decrease the cost This can be confirmed by the empirical results of this paper. At present, general enterprise accounting is done through ERP system. However, since the ERP system does not have an analysis system for each sales and management cost, the current system has difficulty in knowing the budget item for each cost each time the expenditure resolution for each cost item is made, It is a reality that the expenditure plan must be managed separately and it is inconvenient to keep it. However, if this practical difficulty is solved by the cost analysis system such as sales management cost, the present accounting information system will be further developed. Furthermore, the management will increase the profit item It is thought that coordination actions can also be prevented in advance.

• Korean Journal of Child Studies
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• v.28 no.1
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• pp.115-128
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• 2007

Participants in this study to develop the Korean version of the Early Childhood Home Observation for Measurement of the Environment(EC-HOME) were 294 3- to 6- year-old children enrolled in a child care center and their parents. Results were that EC-HOME had sufficient internal reliability : Cronbach's ${\alpha}=.80$. Correlation of test-retest ranged from .76~.97. In item-analysis, 9 items with low 'corrected item-total correlation' were removed resulting in 30 items. Factor analysis confirmed 6 factors : 1) Learning Material, 2) Learning Stimulation, 3) Responsivity, 4) Physical Environment, 5) Language Stimulation, and 6) Variety of Materials. Analysis of the relation of children's home environment to their characteristic variances with parents and developmental functioning showed high internal consistency and convergent validity of the sub-scales.

• International Commerce and Information Review
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• v.8 no.4
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• pp.89-104
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• 2006

Though weight manufacturing has in national gross production is decreasing, it has still a decisive role in economic growth of Korea, and foreign competitiveness of manufacturing has a great influence on our whole economy. Therefore, as this study speculates export competitiveness of manufacturing item by item, the results can be used for selection of strategic export-oriented products. The results of the analysis are summarized as follows: first, products that are found as competitive through analysis of trade specialization indexes are plastic, rubber, fabric, home electronic appliances, computers, communication equipment, automobiles and their spare parts. Second, electronic-electric industry such as semi-conduits, communication equipment, home electronics, computers was decided as advantageous through analysis of comparative advantages at present, while paper, print and publishing, and leather industries were classified as comparatively disadvantageous. Its political implications are presented as follows: Private corporations should develop more advanced technology and government should give more support to secure export competitiveness of manufacturing toward America. Governmental policies should be prepared to induce consistent and daring investment to technology-intensive products for export products with high-added value.

• Journal of The Korean Association For Science Education
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• v.10 no.2
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• pp.11-24
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• 1990

The objectives of this study are to find out the research methodology about misconception, the types of scientific concepts to be misconcepted the analysis methodology of causes of misconception, and remediation methodology of misconception. The research methods of this study are descriptive ques tionnare, interview, classroom observation and curriculum analysis. The results of this study are: ${\circ}$ The descriptive questionnaire is sufficient to obtain children's ideas. ${\circ}$ The types of science concepts to be misconcepted are 'the invisible natural phenomena,' 'the vague Understanding', 'the contents of teachers' lecture', 'the lack of children's cognitive development,'and 'the influence of nursery stories.' ${\circ}$ The Cause analysis methods of misconception are that the analysis of the cognitive level of the questionnaire items, the examining the item concepts are taught or not and the investigation about the agreement of the cognitive level of the questionnaire item and children. ${\circ}$ Remediation methods are visualijation and instrustion of invisible natural phenomena, concrete presentation of the scientific concepts, and acceleration of the cognitive development.

• Journal of Families and Better Life
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• v.16 no.4
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• pp.155-166
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• 1998

The purpose of this study was to develop ' the Behavior Problem Scale for Children and Adolescence' The 518 subjects were selected from 5th and 6th grades of elementary schools and first and second grades of middle schools in Pusan. Statistics used for data analysis were χ2 cramer's V, factor analysis multi-regression Pearson's r, Cronbach's a. The major finding of this study were as follows 1) 80 items of the 159 item scale were acceptable through item discriminant method The discriminant coefficients of the items(Cramer's V) ranged from .48 to .81. 2) 6 factors(shyness aggression hyperactivity withdrawal anxious immature) extracted from factor analysis,. Multi-regression analysis conducted to reduce the length of scale have drawn 42 items for 'the Behavior Problem Scale Children and Adolescence' 3) Reliability coefficients(Cronbach's a) of this scale was 94.