• Communications for Statistical Applications and Methods
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• v.18 no.5
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• pp.625-636
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• 2011

This paper proposes two parametric entropy estimators, the minimum variance unbiased estimator and the maximum likelihood estimator, for the lognormal distribution for a comparison of the properties of the two estimators. The variances of both estimators are derived. The influence of the bias of the maximum likelihood estimator on estimation is analytically revealed. The distributions of the proposed estimators obtained by the delta approximation method are also presented. Performance comparisons are made with the two estimators. The following observations are made from the results. The MSE efficacy of the minimum variance unbiased estimator appears consistently high and increases rapidly as the sample size and variance, n and ${\sigma}^2$, become simultaneously small. To conclude, the minimum variance unbiased estimator outperforms the maximum likelihood estimator.

• Journal of Information Technology Services
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• v.18 no.3
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• pp.95-115
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• 2019

In recent years, social media that has emerged with the development of network technology has changed the channels of information dissemination. The social Q&A community is a platform for knowledge-sharing activities in a question-and-answer manner based on Web 2.0. In knowledge-sharing activities, valuable new knowledge continues to be produced and will surely bring great benefits to individuals or businesses. In the social Q&A community, the user's subjective factors play a crucial role in influencing the user's continued use and participation in knowledge-sharing activities. In order for users to actively participate in knowledge-sharing activities in the community, it needs to grasp their subjective ideas. This study explores the issue of sharing knowledge by users of the social Q&A community "Zhihu", or how to drive community revitalization efforts from these. The three factors self-efficacy, self-development motivation, and social comparison tendencies were derived, and identify their relationship with knowledge-sharing activities and community-boosting efforts through empirical analysis. In addition, the influence of knowledge acquisition on knowledge provision was investigated through sense of reciprocity. Implications of the study findings and the future research directions were also discussed.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.1
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• pp.102-108
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• 2004

The present experiment was conducted to assess the efficacy of methionine hydroxy analogue free fatty acid (MHAFA) in comparison to DL-methionine (DL-Met) utilizing day-old commercial broiler chicks (n=300). The chicks were randomly distributed into 30 groups of 10 chicks each. Three dietary treatments, viz. D1-maize-soybean meal based basal diet (Control), D2- control diet supplemented with DL- methionine to meet its requirements and D3-control supplemented with MHA-FA @ 1.54 times of DL-methionine used in D2, were formulated. Each dietary treatment was offered to 10 replicated groups of chicks following completely random design (CRD). The chicks fed on supplemental DL-Met had significantly higher (p<0.01) gain in body weight, followed by MHA-FA group and control during 0-3 weeks of age. During overall growth period (0-6 weeks), chicks in DL-Met and MHA-FA groups grew better (p<0.01) than those in control. Feed conversion ratio (FCR) improved (p<0.01) on supplementation of either DL- Met or MHA-FA in the basal (Control) diet during 0-3 weeks of age. The FCR for overall period, however, did not differ statistically (p>0.05) amongst the treatments. The eviscerated yields emanated from diets with DL-Met or MHA-FA were higher (p<0.01) than that in Control. Abdominal fat pad was also more (p<0.01) in broilers fed control diet than in DL-Met or MHA-FA supplemented group. Breast yield was higher (p<0.05) in MHA-FA fed broilers than those fed DL-methionine supplemented or un-supplemented diets. The efficacy of MHA-FA in comparison to DL-Met for growth was 62.11, 64.82 and 63.88% and for feed efficiency was 62.98, 67.73 and 64.01% at 0-3, 3-6 and 0-6 weeks of age, respectively, while it was 65.85, 71.40 and 67.49% for eviscerated yield, abdominal fat pad reduction and breast yield at 6 weeks of age, respectively.

• Asia-Pacific Journal of Business
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• v.1 no.2
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• pp.65-81
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• 2010

This paper examines factors like career orientation, social & cultural perception and self-efficacy that influence on entrepreneurial intention of college students, and also comparison of determinant factors of the entrepreneurial intention among Korean and Chinese students. First, in terms of technical competence orientation, security orientation, autonomy orientation, Korean students showed higher than Chinese students, while Korean students showed lower entrepreneurial creativity orientation. In terms of corporate image and entrepreneurial intention, Korean students showed lower than Chinese students. Second, entrepreneurial creativity orientation out of career orientation among Korean and Chinese Students had significant positive effects on entrepreneurial intention, while security orientation had marginally negative effects on entrepreneurial intention. Entrepreneurial self-efficacy and corporate image had the positive effects on entrepreneurial intention together. The Chinese students, however, had the positive effects in network environment for analysis in this study only.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.1
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• pp.59-67
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• 2014

Purpose: The present study was aimed to compare the results of disinfection efficacy tested by membrane filtration method with dilution-neutralization method to develop the standard methods for evaluating disinfection efficacy of contact lens care products and to provide the result of disinfection efficacy of commercially available contact lens care products in domestic market. Methods: The results of disinfection efficacy against Staphylococcus aureus, Pseudomonas aeruginosa, Serratia marcescens, Candida albicans evaluated by membrane filtration method as a FDA standard and dilution-neutralization method as newly being a KFDA standard were compared and the disinfection efficacy of 16 multi-purpose solutions was further evaluated. Results: The disinfectants and contact lens care products having strong disinfection efficacy showed same results in both membrane filtration method and dilution-neutralization method. In case of contact lens care products having weak disinfection efficacy, the number of micro-organisms was not able to count since the colony was aggregated when evaluated by membrane filtration method. However, the number of micro-organisms was able to exactly count when evaluated by dilution-neutralization method. In addition, some commercially available contact lens care products did not meet disinfection standard and especially, their disinfection effect was often weak against Serratia marcescen and Candida albicans. Conclusions: It is concluded that dilution-neutralization method will be useful to evaluate disinfection efficacy since it is possible to count micro-organisms more precisely even with small amount of sample and check the results faster compared with membrane filtration method.

• Korean Journal of Food Science and Technology
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• v.39 no.3
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• pp.342-347
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• 2007

The dried fruit of the Rubus coreanus, which is well-known in Korea and referred to as 'Bokbunja,' has been employed as a traditional medicine for centuries. This crude drug has been utilized in Korea for the management of impotence, spermatorrhea, enuresis, asthma, and allergic diseases. Our previous study demonstrated that the ethanol extracts of R. coreanus have anti-inflammatory effects. The principal objective of the present study was to conduct a comparison of the anti-inflammatory effects of the ethanol extracts of R. coreanus and R. occidentalis; here, we tested the unripe (URCE), half-ripened (HRCE), and ripened fruits (RCE) of R. coreanus, and the unripe (UROE), half-ripened (HROE), and ripened fruits (ROE) of R. occidentalis. We found that URCE, UROE, HRCE, and HROE reduced the production of nitric oxide and prostaglandin $E_{2}$ as well as pro-inflammatory cytokines in lipopolysaccharide-stimulated RAW264.7 murine macrophages. Interestingly, the R. coreanus extracts showed stronger inhibitory effects on the production of these inflammatory mediators than the R. occidentalis extracts.

• Journal of Nutrition and Health
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• v.45 no.1
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• pp.64-79
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• 2012

The purpose of this study was to compare differences in role conflict, self efficacy, job satisfaction, and job involvement perceived by school nutrition teachers and dietitians. A total of 335 female school nutrition teachers and dietitians from Incheon area were surveyed by a self-report questionnaire in November 2010. Collected data were processed using SPSS 15.0. The reliability of the questionnaire was tested and differences between the two groups were analyzed using the Student's t-test, the chi-square test, and a two-way analysis of variance (ANOVA). The job satisfaction level of nutrition teachers was higher than that of dietitians. The effect of role conflict and job satisfaction for nutrition teachers and dietitians was different according to age. In addition, self-efficacy, job satisfaction, and job involvement of nutrition teachers and dietitians were influenced by their annual salaries. The frequency of meals served also affected role conflict, job satisfaction, and job involvement of the nutrition teachers and dietitians, and the effect of job involvement by the nutrition teachers and dietitians was different according to meal service type. Therefore, it is necessary to establish strategies for resolving role conflicts among school foodservice specialists and improve their self-efficacy for enhancing consumer's satisfaction with the general quality of school food service. These efforts may contribute to job satisfaction and job involvement of food service specialists and ultimately to the productivity of food service and the establishment of food service specialist roles.

• Journal of Chest Surgery
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• v.56 no.2
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• pp.90-98
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• 2023

Background: Atrial fibrillation (AF) is the most common type of cardiac arrhythmia. Totally thoracoscopic ablation (TTA) is a surgical treatment showing a high success rate as a hybrid procedure with radiofrequency catheter ablation to control AF. This study compared the early complications of warfarin and non-vitamin K antagonist oral anticoagulants (NOACs) in patients who underwent TTA. Methods: This single-center retrospective cohort study enrolled patients who underwent planned TTA for AF from February 2012 to October 2020. All patients received postoperative anticoagulation, either with warfarin or a NOAC (apixaban, rivaroxaban, dabigatran, or edoxaban). Propensity score matching was performed for both groups. Early complications were assessed at 12 weeks after TTA and were divided into efficacy and safety outcomes. Both efficacy and safety outcomes were compared in the propensity score-matched groups. Results: Early complications involving efficacy outcomes, such as stroke and transient ischemic attack, were seen in 5 patients in the warfarin group and none in the NOAC group. Although the 2 groups differed in the incidence of efficacy outcomes, it was not statistically significant. In safety outcomes, 11 patients in the warfarin group and 24 patients in the NOAC group had complications, but likewise, the between-group difference was not statistically significant. Conclusion: Among patients who underwent TTA, those who received NOACs had a lower incidence of thromboembolic complications than those who received warfarin; however, both groups showed a similar bleeding complication rate. Using a NOAC after TTA does not reduce efficacy and safety when compared to warfarin.

• The Journal of Korean Academic Society of Nursing Education
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• v.17 no.1
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• pp.110-119
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• 2011

Purpose: This study was conducted to identify the consumption of alcohol as well as to compare drinking refusal self-efficacy and mental health between an average drinking group and a problem drinking group of Korean nursing students. Methods: A questionnaire using the Alcohol Use Disorders Identification Test (AUDIT) measuring drinking refusal self-efficacy and mental health was given to 938 students of two universities in Gyeongsangnam-do. Results: Among the respondents 381 (40.6%) were problem drinkers. The score of alcohol consumption in the AUDIT were 3.38 for the average group and 12.50 for the problem drinking group. There were significant differences between the average group and problem drinking group in age, living place, smoking, parent's drinking, age of the first drink and reasons for first drink. Participants of the average group had significantly higher drinking refusal self-efficacy than the problem drinking group. Regarding mental health, there were differences between the two groups in attempted suicide. The risk factors significantly associated with problem drinking were living place, smoking and reasons for the initial drink. Conclusion: These results provide guidance for developing strategies, such as an educational program, to promote safe alcohol consumption in nursing students.

• Korean Journal of Radiology
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• v.25 no.2
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• pp.199-209
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• 2024

Objective: This study aimed to compare therapeutic efficacy and technical outcomes between adjustable electrode (AE) and conventional fixed electrode (FE) for radiofrequency ablation (RFA) of benign thyroid nodules. Materials and Methods: Between 2013 and 2021, RFA was performed on histologically proven benign thyroid nodules. For the AE method, AE length ≥ 1 cm with higher power and < 1 cm with lower power were utilized for ablating feeding vessels and nodules, especially those near anatomical structures, respectively. The therapeutic efficacy (volume reduction rate [VRR], complication rate, and regrowth rate) and technical outcomes (total energy delivery, ablated volume/energy, RFA time, and ablated volume/time) of FE and AE were compared. Continuous parameters were compared using a two-sample t-test or Mann-Whitney U test, and categorical parameters were compared using a chi-squared test or Fisher's exact test. Results: A total of 182 nodules (FE: 92 vs. AE: 90) in 173 patients (mean age ± standard deviation, 47.0 ± 14.7 years; female, 90.8% [157/173]; median follow-up, 726 days [interquartile range, 441-1075 days]) were analyzed. The therapeutic efficacy was comparable, whereas technical outcomes were more favorable for AE. Both electrodes demonstrated comparable overall median VRR (FE: 92.4% vs. AE: 84.9%, P = 0.240) without immediate major complications. Overall regrowth rates were comparable between the two groups (FE: 2.2% [2/90] vs. AE: 1.1% [1/90], P > 0.99). AE demonstrated a shorter median RFA time (FE: 811 vs. AE: 627 seconds, P = 0.009). Both delivered comparable median energy (FE: 42.8 vs. AE: 29.2 kJ, P = 0.069), but AE demonstrated higher median ablated volume/energy and median ablated volume/time (FE: 0.2 vs. AE: 0.3 cc/kJ, P < 0.001; and FE: 0.7 vs. AE: 1.0 cc/min, P < 0.001, respectively). Conclusion: Therapeutic efficacy between FE and AE was comparable. AE demonstrated better technical outcomes than FE in terms of RFA time, ablated volume/energy, and ablated volume/time.