• Industrial Engineering and Management Systems
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• v.13 no.4
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• pp.454-462
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• 2014

Retention of possible churning customer is one of the most important issues in customer relationship management, so companies try to predict churn customers using their large-scale high-dimensional data. This study focuses on dealing with large data sets by reducing the dimensionality. By using six different dimension reduction methods-Principal Component Analysis (PCA), factor analysis (FA), locally linear embedding (LLE), local tangent space alignment (LTSA), locally preserving projections (LPP), and deep auto-encoder-our experiments apply each dimension reduction method to the training data, build a classification model using the mapped data and then measure the performance using hit rate to compare the dimension reduction methods. In the result, PCA shows good performance despite its simplicity, and the deep auto-encoder gives the best overall performance. These results can be explained by the characteristics of the churn prediction data that is highly correlated and overlapped over the classes. We also proposed a simple out-of-sample extension method for the nonlinear dimension reduction methods, LLE and LTSA, utilizing the characteristic of the data.

• Journal of Korean Physical Therapy Science
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• v.9 no.2
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• pp.77-85
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• 2002

Patient satisfaction is an important factor in evaluating the quality of care. Patient satisfaction may be used to evaluate provider services and facilities, and used to predict the patient returns to a facility. The patients decision whether the patient returns to a facility or whether the patient recommends the facility to other people may be affected by a variety of factors of patient satisfaction. This study is to develop and test of a translated and modified Goldstein's instrument that measures patient satisfaction among physical therapists patients and clients. A self-administered questionnaire survey was conducted in Seoul, Chung-Joo and Bu-Cheon cities. Survey data was obtained from 743 patients who visited the physical therapy practice at university hospitals, general hospitals and clinics. The instrument developed by Goldstein was used and translated into Korean. Several items were added to the instrument. Patient's opinions of service in each domain measured using 5-point Likert-type scales that ranged from strongly disagree to strongly agree. Principal components analysis with varimax rotation was used to indicate which questions examined similar components of patient satisfaction. Component analysis indicated eight scales (kindness, scheduling, recommendation, convenience of parking, privacy, and waiting time). Different types of validity were established well. The coefficient of reliability (Cronbach alpha =.97) obtained for the instrument was clearly within a desired range.

• Research in Community and Public Health Nursing
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• v.31 no.2
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• pp.130-142
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• 2020

Purpose: The purpose of this study was to verify the validity and reliability of the Korean version of the Pain in Older Adults Knowledge Survey (K-POAKS) to assess knowledge of pain in older adults including people with dementia for use in long-term care hospital nurses. Methods: Survey data were collected from a convenience sample of 179 nurses who have worked in long-term care hospitals in B, D and U cities. The Kuder-Richardson Formula 20 for internal consistency for test reliability was conducted. The content, criterion-related and construct validity were evaluated using SPSS/WIN 22.0. Results: The KR 20 was .75 and Content Validity Ratio (CVR) was a range of 0.84~1.00. The criterion-related validity was positively correlated with attitudes (r=.28, p<.001) and performance (r=.21, p=.004). The construct validity of K-POAKS was analyzed by conducting the principal component method using the exploratory factor analysis varimax rotation, and seven factors were derived above the eigenvalue of 1.0. The seven factors explained 58.5% of the total variation. Conclusion: The Korean version of the POAKS showed satisfactory internal reliability, content validity, criterion-related validity and construct validity. These results suggest that the K-POAKS could be used as a suitable tool to measure the knowledge of the aged people's pain, including that of dementia patients for long-term care hospital nurses.

• Journal of Korean Critical Care Nursing
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• v.8 no.1
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• pp.50-61
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• 2015

Purpose: The purpose of this study was to develop a valid tool for measuring the work environment of Korean nurses and test the validity and reliability of the instrument. Methods: This is a methodological study for developing and testing a measurement tool. The conceptual framework for the tool was formed through a literature review and in-depth interviews with clinical nurses. 260 meaningful statements were derived through this process, and 59 of the primary items were generated out of these statements. On the basis of the content validity test, 41 items were selected for the preliminary tool. A total of 350 nurses from 7 hospitals responded to the preliminary questionnaire in October 2011. Results: After the item analysis and the principal component analysis using varimax rotation methods, 11 items were deleted. Considering the conceptual framework and the scree plot, we extracted 4 factors from the final 30 items. These factors were organizational support, head nurse's leadership, support system, and relationship with coworkers, and their total variance was 54.4%. The value of Cronbach's ${\alpha}$ of the final tool was 0.92. Conclusion: The above findings revealed that the Korean Nursing Work Environment Scale (K-NWES) is an appropriate, valid, and reliable tool for evaluating the work environment of Korean nurses. Further research to perform a criterion validity test of the K-NWES is needed.

• Journal of Korean Academy of Nursing
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• v.41 no.1
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• pp.129-140
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• 2011

Purpose: This study was done to develop an instrument for measuring intellectual capital and assess its validity and reliability in identifying the components, human capital, structure capital and customer capital of intellectual capital in hospital nursing organizations. Methods: The participants were 950 regular clinical nurses who had worked for over 13 months in 7 medical hospitals including 4 national university hospitals and 3 private university hospitals. The data were collected through a questionnaire survey done from July 2 to August 25, 2009. Data from 906 nurses were used for the final analysis. Data were analyzed using descriptive statistics, Cronbach's alpha coefficients, item analysis, factor analysis (principal component analysis, Varimax rotation) with the SPSS $PC^+$ 17.0 for Windows program. Results: Developing the instrument for measuring intellectual capital in hospital nursing organizations involved a literature review, development of preliminary items, and verification of validity and reliability. The final instrument was in a self-report form on a 5-point Likert scale. There were 29 items on human capital (5 domains), 21 items on customer capital (4 domains), 26 items on structure capital (4 domains). Conclusion: The results of this study may be useful to assess the levels of intellectual capital of hospital nursing organizations.

• Journal of the Korean Society of Costume
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• v.51 no.1
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• pp.87-96
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• 2001

This study, dealing with obese bodily figures from the viewpoint of garment shape, was conducted with obese male children of late school ages(nine to eleven years old) to provide data for making ready-made clothing for obese children by directly measuring and analysing the bodily figure of the upper body of them. The results of the study are summarized as follows. 1. According to the basic statistics, for most of obese children the values of the measuring items by ages appeared to be large, and the results of comparison with the National Anthropometric Survey of Korea made in 1997 showed that the values were more large than those of standard physical conditions. 2. It was shown that in the correlation between items the upper breast circumference had a high correlation with all items, and the weight did with the following items such as circumference, height, width and thickness. 3. The results of the principal component analysis showed that six main components hand an explainable power of more than 75.60% for all materials. The first factor was thickness and obesity of the upper body, the second one the height, the third one the length of front and rear sides, the fourth one the width of neck, the fifth one the length of shoulder, and the sixth one the breast width and the wrist circumference.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.920-925
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• 2001

A study on the topology optimization of a multi-spectral camera for space-use is presented. A multi-spectral camera for space-use experiences degradation of optical image in the space, which can not be detected on the optical test bench on the earth. An optical surface deformation of a primary mirror, which is a principal component of the camera system, under the self-weight loading is an important factor affecting the optical performance of the whole camera system. In this study, topology optimization of the primary mirror of the camera is presented. Total mass of the primary mirror is given as a constraint to the optimization problem. The sensitivities of the objective function and constraint are calculated by direct differentiation method. Optimization procedure is carried out by an optimality criterion method using the sensitivities of the objective function and the constraint. As a preliminary example, topology optimization considering a self-weight loading is treated. For practical use, the polishing pressure is included as a loading in the topology optimization of the primary mirror. Results of the optimized design topology for the primary mirror with varying mass ratios are presented.

• Asian Journal of Business Environment
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• v.5 no.3
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• pp.5-15
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• 2015

Purpose - This paper aims to identify and rank factors that influence impulse buying behavior among shoppers in Dubai. Research design, data, and methodology - Questionnaires were collected from 168 Dubai shoppers using non-probability quota sampling. Factor Analysis was completed to identify factors triggering impulse buying traits. Results - Six antecedent factors were identified: hedonism, in-store influences, product related influences, socialization, promotional activities, and convenience. Surprisingly, product related influences were the most significant in stimulating impulse buying behavior. Conclusions - This research suggests that a multitude of factors affect shopper propensity for impulse buying, with non-economic factors like product and in-store related influences having a significant impact. Hence, retail managers should concentrate on these in merchandising and promotional efforts. Against the backdrop of Dubai, one of the biggest retail destinations, this study contributes to present knowledge on impulse buying behavior. In terms of shopper inclinations and likeliness to purchase products, it highlights how shoppers respond to special in-store displays and discount offerings. For marketers, the findings regarding relative significance of various factors may help in strategies to attract consumers.

• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.587-593
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• 2010

Three hundred and seventy-four rhizobacteria were isolated from the rhizosphere soil (RS) or rhizoplane (RP) of Echinochloa crus-galli, Carex leiorhyncha, Commelina communis, Persicaria lapathifolia, Carex kobomugi, and Equisetum arvense, grown in contaminated soil with petroleum and heavy metals. The isolates were screened for plant growth-promoting trait (PGPT), including indole acetic acid (IAA) productivity, 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity, and siderophore(s) synthesis ability. IAA production was detected in 86 isolates (23.0%), ACC deaminase activity in 168 isolates (44.9%), and siderophore(s) synthesis in 213 isolates (57.0%). Among the rhizobacteria showing PGPT, 162 isolates had multiple traits showing more than two types of PGPT. The PGPT-possesing rhizobacteria were more abundant in the RP (82%) samples than the RS (75%). There was a negative correlation (-0.656, p<0.05) between the IAA producers and the ACC deaminase producers. Clustering analysis by principal component analysis showed that RP was the most important factor influencing the ecological distribution and physiological characterization of PGPT-possesing rhizobacteria.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.6 no.5
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• pp.777-782
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• 2002

This study will offer multimodal recognition instead of an existing monomodal bioinfomatics by using facial multi-feature to improve the accuracy of recognition and to consider the convenience of user . Each bioinfomatics vector can be found by the following ways. For a face, the feature is calculated by principal component analysis with wavelet multiresolution. For a lip, a filter is used to find out an equation to calculate the edges of the lips first. Then by using a thinning image and least square method, an equation factor can be drawn. A feature found out the facial parameter distance ratio. We've sorted backpropagation neural network and experimented with the inputs used above. Based on the experimental results we discuss the advantage and efficiency.