• Journal of Cardiovascular Imaging
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• v.30 no.4
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• pp.307-319
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• 2022

BACKGROUND: Current guidelines indicate electrical dyssynchrony as the major criteria for selecting patients for cardiac resynchronization therapy, and 25-35% of patients exhibit unfavorable responses to cardiac resynchronization therapy (CRT). We aimed to evaluate different cardiac mechanical dyssynchrony parameters in heart failure patients using current echo-Doppler modalities and we analyzed their association with electrical dyssynchrony. METHODS: The study included 120 heart failure with reduced ejection fraction (HFrEF) who underwent assessments for left ventricular mechanical dyssynchrony (LVMD) and interventricular mechanical dyssynchrony (IVMD). RESULTS: Patients were classified according to QRS duration: group I with QRS < 120 ms, group II with QRS 120-149 ms, and group III with QRS ≥ 150 ms. Group III had significantly higher IVMD, LVMD indices, TS-SD speckle-tracking echocardiography (STE) 12 segments (standard deviation of time to peak longitudinal strain speckle tracking echocardiography in 12 LV-segments), and LVMD score compared with group I and group II. Group II and group III were classified according to QRS morphology into left bundle branch block (LBBB) and non-LBBB subgroups. LVMD score, TS-SD 12 TDI, and TS-SD 12 STE had good correlations with QRS duration. CONCLUSIONS: HFrEF patients with wide QRS duration (> 150 ms) had more evident LVMD compared with patients with narrow or intermediate QRS. Those patients with intermediate QRS duration (120-150 ms) had substantial LVMD assessed by both TDI and 2D STE, regardless of QRS morphology. Subsequently, we suggest that LVMD indices might be employed as additive criteria to predict CRT response in that patient subgroup. Electrical and mechanical dyssynchrony were strongly correlated in HFrEF patients.

• Bulletin of the Korean Mathematical Society
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• v.52 no.2
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• pp.619-626
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• 2015

This paper considers regularity for the p-harmonic and Ostwald-de Waele flows. Some Serrin's type regularity criteria are established for 1 < p < 2.

• Architectural research
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• v.14 no.4
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• pp.143-152
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• 2012

A form-finding procedure is presented for planar tensegrity structures. Notably, a simple decision criteria is proposed to select the desirable candidate position vector from the unitary matrix produced by the eigenvalue decomposition of force density matrix. The soundness of the candidate position vector guarantees faster convergence and produces a desirable form of tensegrity without any member having zero-length. Several numerical examples are provided to demonstrate the capability of the proposed form-finding process.

• Journal of the Ergonomics Society of Korea
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• v.29 no.3
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• pp.287-296
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• 2010

The purpose of this research is to analyze priority of the elderly user interface (UI) evaluation criteria based on user's lifestyle. Since the elderly population will occupy over 20% of the all Korean population in the near future, we need to know older users' needs and information because elderly users will be main customers in the super-aged society. This paper investigated the definition of elderly users and characteristics demographically, socio-economically, and physically/cognitively. A total of 238 questionnaires from older users were analyzed based on a segmentation table for the elderly developed by the previous study. According to factor analysis and cluster analysis, 6 types of lifestyle and 4 groups of the elderly users were classified, respectively. The priority of UI evaluation criteria for large electronic home appliances and mobile products was analyzed by analyses of variance (ANOVAs). The results indicated that the priority of (physical, emotional, and cognitive) UI criteria was significantly different among elderly users' lifestyles for both home appliances and mobile products. Consequently, the results of this study may help the company develop some competitive silver products and give higher satisfaction to the elderly users by suggesting different priority of UI evaluation criteria according to the target elderly group. The results may also contribute to revitalize national economy by significantly increasing senior market shares.

• Journal of Family Resource Management and Policy Review
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• v.11 no.4
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• pp.1-20
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• 2007

The purpose of this study was to identify the criteria of evaluating a price-comparison website, and to investigate the consumers' perceived importance and satisfaction of each criterion. Also, it compared both the importance and satisfaction levels based on consumers' socio-economic and Internet-usage characteristics. Data for this study came from a questionnaire completed by consumers (n=417), who had used the price-comparison website, and were analyzed through factor analysis, t-test, and ANOVA. The findings of the study were as follows: First, the evaluation criteria of the price-comparison website were categorized into five variety of information, accuracy, convenience, credibility, and the website system. Second, convenience of searching information was seen by consumers as both the most important and most satisfactory criterion. Variety of information was also considered important. For most of the evaluation criteria, the level of consumers' satisfaction was significantly lower than the level of consumers' recognized importance. Third, consumers in their 20s, students, and housewives were less likely to be satisfied by the price-comparison website overall. Older people were less likely to be satisfied with the convenience of the website, and the higher-income group was less likely to be satisfied with the variety of information on hand.

• Safety and Health at Work
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• v.3 no.2
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• pp.110-116
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• 2012

Establishing a causal relationship between factors at work and disease is difficult for occupational physicians and researchers. This paper seeks to provide arguments for the judgement of evidence of causality in observational studies that relate work factors to disease. I derived criteria for the judgement of evidence of causality from the following sources: the criteria list of Hill, the approach by Rothman, the methods used by International Agency for Research on Cancer (IARC), and methods used by epidemiologists. The criteria are applied to two cases of putative occupational diseases; breast cancer caused by shift work and aerotoxic syndrome. Only three of the Hill criteria can be applied to an actual study. Rothman stresses the importance of confounding and alternative explanations than the putative cause. IARC closely follows Hill, but they also incorporate other than epidemiological evidence. Applied to shift work and breast cancer, these results have found moderate evidence for a causal relationship, but applied to the aerotoxic syndrome, there is an absence of evidence of causality. There are no ready to use algorithms for judgement of evidence of causality. Criteria from different sources lead to similar results and can make a conclusion of causality more or less likely.

• Journal of Korean Academy of Nursing
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• v.34 no.3
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• pp.525-533
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• 2004

Purpose: The purpose of this study was to develop a program promoting adjustment to hospital life and determining its effectiveness for school aged children. Method: The sample group consisted of 76 hospitalized children in 2 University Hospitals located in Busan. The experimental group was given the program on admission and feedback was obtained on the 3rd day and again 24 hours later. Data was analyzed using t-test and ANOVA in the SPSS program package. Result: There were significant differences, in information(t=4.235, p=0.000) and coping effort criteria (t=2.922, p=0.005) between the experimental and control groups. There was a non-significant difference in attitude criteria between the two groups(t=1.009, p=0.316). Conclusion: It was found that the adjustment promoting program for hospital life for school aged children was effective, but not enough to promote self-esteem. The program, based on a learning theory, was improved and shown to be an effective and strong method to promote adjustment of school-aged children.

• Knowledge Management Research
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• v.9 no.1
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• pp.1-21
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• 2008

The present study investigatesthe reliability and validity of the innovation leadership scale. Originally the seven factors with 25 items were developed through literature review. With a sample of 177 employees in a large company, the results of factor analyses showed that the five-factor model with 14 items had a better fit to the data than the seven-factor model. These five factors were innovativeness pursue, problem solving, vision presentation, risk-taking, and showing initiative. All of these factors were significantly related to various criteria such as identification with the group, attachment to the group, organizational commitment, and supervisor satisfaction, confirming criterion-related validity of the scale. Results of multiple regression analyses showedthat risk taking and showing initiative were more important predictors in explaining criteria. Finally, implications and limitations were discussed. The findings suggest that the key factors of innovation leadership were initiative and risk-taking.

• English Language & Literature Teaching
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• v.15 no.2
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• pp.169-184
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• 2009

The purpose of this study is to identify the most important factor(s) that contribute(s) to the overall oral proficiency and to examine whether the factor(s) play(s) a different role depending on the proficiency level of learners. Learners were divided into novice group and advanced group and were asked to produce an oral recording of a story based on a comic strip. The recordings were transcribed and graded by three raters. According to the results, the raters attained high inter-rater reliability when assessing advanced learners. However, the reliability level became considerably lower in the assessment of novice learners. The best predictor of oral proficiency among novice learners was sociolinguistic competence and fluency, while grammatical competence and fluency were the strongest predictors for advanced learners. The results suggest the need for a separate assessment tool for different proficiency levels and the need for a different focus in the classroom depending on the learners' proficiency level.

• Journal of the Korean Home Economics Association
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• v.39 no.11
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• pp.145-160
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• 2001

The purpose of this study was to classify consumer groups according to shopping attitude and analyze buying intention and evaluation criteria of apparel product, opinion to CATV home shopping among consumer groups. The subjects of this study were 270 women living in Chonbuk and Chonnam regardless their experiene in CATV home shopping. For data analysis frequency, percentage, mean,1-test, factor analysis, Cluster Analysis, Duncan Multiple Range test, were conducted. The results were as follows; First, the type of shopping attitude were classified into the following subdivisions: merchandise assortment oriented type, adventure oriented type, indifferent type, economy oriented group, recreational oriented group. Second, shopping attitude were shown to have the significant differences according to education, the structure of family, working in double hamess. Third, the significant differences among the classified shopping attitude groups were found in buying intention, evaluation criteria of apparel product, and opinion to CATV home shopping.