• Journal of Life Science
• /
• v.33 no.3
• /
• pp.242-251
• /
• 2023

The purpose of this study was to investigate the effects of 8-week β-hydroxybutyrate (β-HB) administration with and without endurance exercise training on endurance exercise performance and skeletal muscle protein synthesis and degradation using a mouse model. Forty-eight male wild-type ICR mice (8 weeks old) were randomly divided into four groups: sedentary control (Sed+Con), (Sed+Con), sedentary β-HB (Sed+β-HB), exercise control (Exe+Con), and exercise β-HB (Exe+β-HB). β-HB was dissolved in PBS (150 mg/ml) and injected subcutaneously daily (250 mg/kg) for 8 weeks. Mice performed 5 days/week of a 20 min treadmill running exercise for 8 weeks. The running exercise was carried out at a speed of 10 m/min at a 10° incline for 5 min, and then the speed was increased by 1 m/min for every 1 min of the remaining 15 min. Following 8 weeks of treatments, visceral fat mass and skeletal muscle mass, blood parameters, and the markers for autophagy and protein synthesis were analyzed. The data were analyzed with one-way ANOVA (p<0.05) using the SPSS 21 program. Eight weeks of Exe+β-HB treatment significantly lowered blood lactate levels compared with the other three groups (Sed+Con, Sed+β-HB, and Exe+β-HB) Exe+β-HB) (p<0.05). Eight weeks of Exe+β-HB significantly increased maximal running time (time to exhaustion) compared with the Sed+Con and Exe+Con groups (p<0.05). Eight weeks of β-HB administration significantly decreased autophagy flux and autophagy-related proteins in the skeletal muscle of mice (p<0.05). Conversely, the combined treatment of β-HB and endurance exercise training increased protein synthesis (mTOR signaling and translation) (p<0.05). The 8-week β-HB treatment and endurance exercise training had synergistic effects on the increase in endurance performance, increase in protein synthesis, and decrease in protein degradation in the skeletal muscle of mice.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.28 no.1
• /
• pp.1-18
• /
• 2023

The East Sea, one of the regions where the most rapid warming is occurring, is known to have important implications for the response of the ocean to future climate changes because it not only reacts sensitively to climate change but also has a much shorter turnover time (hundreds of years) than the ocean (thousands of years). However, the processes underlying changes in seawater characteristics at the sea's deep and abyssal layers, and meridional overturning circulation have recently been examined only after international cooperative observation programs for the entire sea allowed in-situ data in a necessary resolution and accuracy along with recent improvement in numerical modeling. In this review, previous studies on the physical characteristics of seawater at deeper parts of the East Sea, and meridional overturning circulation are summarized to identify any remaining issues. The seawater below a depth of several hundreds of meters in the East Sea has been identified as the Japan Sea Proper Water (East Sea Proper Water) due to its homogeneous physical properties of a water temperature below 1℃ and practical salinity values ranging from 34.0 to 34.1. However, vertically high-resolution salinity and dissolved oxygen observations since the 1990s enabled us to separate the water into at least three different water masses (central water, CW; deep water, DW; bottom water, BW). Recent studies have shown that the physical characteristics and boundaries between the three water masses are not constant over time, but have significantly varied over the last few decades in association with time-varying water formation processes, such as convection processes (deep slope convection and open-ocean deep convection) that are linked to the re-circulation of the Tsushima Warm Current, ocean-atmosphere heat and freshwater exchanges, and sea-ice formation in the northern part of the East Sea. The CW, DW, and BW were found to be transported horizontally from the Japan Basin to the Ulleung Basin, from the Ulleung Basin to the Yamato Basin, and from the Yamato Basin to the Japan Basin, respectively, rotating counterclockwise with a shallow depth on the right of its path (consistent with the bottom topographic control of fluid in a rotating Earth). This horizontal deep circulation is a part of the sea's meridional overturning circulation that has undergone changes in the path and intensity. Yet, the linkages between upper and deeper circulation and between the horizontal and meridional overturning circulation are not well understood. Through this review, the remaining issues to be addressed in the future were identified. These issues included a connection between the changing properties of CW, DW, and BW, and their horizontal and overturning circulations; the linkage of deep and abyssal circulations to the upper circulation, including upper water transport from and into the Western Pacific Ocean; and processes underlying the temporal variability in the path and intensity of CW, DW, and BW.

• Journal of Intelligence and Information Systems
• /
• v.28 no.1
• /
• pp.263-286
• /
• 2022

This study acquires NBA statistical information for a total of 32 years from 1990 to 2022 using web crawling, observes variables of interest through exploratory data analysis, and generates related derived variables. Unused variables were removed through a purification process on the input data, and correlation analysis, t-test, and ANOVA were performed on the remaining variables. For the variable of interest, the difference in the mean between the groups that advanced to the playoffs and did not advance to the playoffs was tested, and then to compensate for this, the average difference between the three groups (higher/middle/lower) based on ranking was reconfirmed. Of the input data, only this year's season data was used as a test set, and 5-fold cross-validation was performed by dividing the training set and the validation set for model training. The overfitting problem was solved by comparing the cross-validation result and the final analysis result using the test set to confirm that there was no difference in the performance matrix. Because the quality level of the raw data is high and the statistical assumptions are satisfied, most of the models showed good results despite the small data set. This study not only predicts NBA game results or classifies whether or not to advance to the playoffs using machine learning, but also examines whether the variables of interest are included in the major variables with high importance by understanding the importance of input attribute. Through the visualization of SHAP value, it was possible to overcome the limitation that could not be interpreted only with the result of feature importance, and to compensate for the lack of consistency in the importance calculation in the process of entering/removing variables. It was found that a number of variables related to three points and errors classified as subjects of interest in this study were included in the major variables affecting advancing to the playoffs in the NBA. Although this study is similar in that it includes topics such as match results, playoffs, and championship predictions, which have been dealt with in the existing sports data analysis field, and comparatively analyzed several machine learning models for analysis, there is a difference in that the interest features are set in advance and statistically verified, so that it is compared with the machine learning analysis result. Also, it was differentiated from existing studies by presenting explanatory visualization results using SHAP, one of the XAI models.

• Asia Marketing Journal
• /
• v.13 no.3
• /
• pp.183-208
• /
• 2011

After more than 25 years of accumulated research evidence, there is little doubt that leadership behavior is related to a wide variety of positive individual and organizational outcomes. Indeed, leadership behavior has been empirically linked to increased employee satisfaction, organizational commitment, extra effort, turnover intention, organizational citizenship behavior, and overall employee performance. However, it is important to point out that although leadership behavior has been linked to a number of positive organizational outcomes, research regarding the antecedents of such behavior is limited. Especially there is little research dealing with the antecedents of inter-organizational leadership behavior. Supply chain leadership can be defined as the activities undertaken by the supply chain leader to influence the management programs and strategies of supply chain members. Supply chain performance is influenced by leadership of supply chain leader. Although research on supply chain leadership can be broadly categorized, many researchers have been preoccupied with analyzing supply chain leadership by the power-influence approach measuring such as control, power, and power bases. Also they have not examined the relationship between leadership and financial performance. This study has started to overcome those research gaps. The purpose of this study is to investigate the effect of relational behaviors on supply chain leadership, and the effect of such leadership behavior on financial performance of supply chain followers. In addition, this study also try to find out moderating variable existing in the relationship. To be concrete, First, this study develops a model of the antecedents of four conceptually distinct forms of relational behaviors such as training, fair reward, offering vision, and inter-organizational communication, and tests the hypothesized differential effects of relational behavior forms on supply chain leadership. Second, this study tests the effect of supply chain leadership on financial performance. Third, this study investigates the extent to which this leadership-performance relationship is moderated by leader ethicality. The reason why this study deals with convenience store supply chain is that there is very strong inter-dependence between a franchisor and its suppliers. Their strong inter-dependence makes their relationship as the relationship between a superior and subordinates and creates an atmosphere that leadership occur without difficulty. For the purpose of empirical testing, 217 respondents of suppliers of convenience store supply chain in Korea were surveyed and the analysis utilizing partial least square model indicated that training, fair reward, inter-organizational communication had positive effects on supply chain leadership, and such leadership had positive effect on financial performance of followers. On the other hand, offering vision had no effect on supply chain leadership. In addition, leader ethicality had moderating effect on the relationship between supply chain leadership and financial performance.

• Journal of Venture Innovation
• /
• v.6 no.3
• /
• pp.149-164
• /
• 2023

Today, when innovation and creativity become increasingly important, management of human resources is a key factor for corporate performance and competitive advantage. Corporate are implementing and introducing various types of support methods for members to achieve goals and improve organizational performance. Organizational culture and organizational trust affect the cognitive and emotional state of members. Furthermore, it can bring about changes in organizational performance such as job stress and job satisfaction. From an institutional point of view, work-life balance is also a major factor affecting organizational performance. The imbalance between work and life leads to a decline in organizational performance, such as decreased morale and dissatisfaction with work. In relation to work-life balance, the low birth rate problem intensified and the importance began to emerge. Therefore, the government has implemented various policy support for workers' work-life balance, and the "52-hour workweek" is a representative example. This study analyzed the effect of organizational culture applying the competitive value model on workers' job stress. In addition, the mediating effects of overtime work per week and organizational trust were analyzed. Job stress corresponds to a prerequisite stage that affects job commitment, job satisfaction, and turnover intention. However, research measuring job stress by organizational performance is insufficient. In addition, there are few studies analyzing the relationship between overtime and organizational performance. Considering this, it is necessary to understand the influence relationship. The results of the study are as follows. First, a hierarchical culture increases the job stress of workers. On the other hand, innovation-oriented, relationship-oriented, and competition-oriented corporate culture reduce job stress. Second, a hierarchical culture has reduced trust in the organization, and other organizational cultures have increased trust in the organization. Third, relationship-oriented and competition-oriented organizational culture reduced overtime. Innovation-oriented, hierarchical-oriented culture increased overtime Fourth, organizational trust and overtime have the effect of mediating organizational culture and job stress. Based on these analysis results, this study presented academic and political implications.

• Journal of Venture Innovation
• /
• v.6 no.4
• /
• pp.41-62
• /
• 2023

Given that SME workers are the driving force of national competitiveness and the basis and cornerstone of the industry, it is meaningful to study workers' job satisfaction and the factors that affect job satisfaction. In addition to variables related to corporate competitiveness and organizational justice, this study introduced variables such as environmental(E) activities, social(S) activities, and governance(G) activities, which th national government uses as major management evaluation indicators. Therefore, a literature study and empirical analysis were conducted on how self-efficacy affects job satisfaction when workers are faced with a changed work environment. To conduct this study, 300 copies of data were collected from workers in small and medium-sized enterprises and used for analysis. For data analysis, the SPSS statistical program (Ver. 25.0) was used. The study finds, first, that product or service quality and employee competency among corporate competitiveness had a significant positive(+) effect on job satisfaction. Secondly, among ESG management activities, social(S) activities and governance(G) activities were found to have a significant positive(+) effect on job satisfaction. Third, among organizational justice, distribution justice and procedural justice were found to have a positive(+) effect on job satisfaction. Fourth, self-efficacy was found to mediate the effect of product or service quality, employee competency, social(S) and governance(G) activities among ESG management activities, and procedural justice among organizational justice on job satisfaction. The academic value of this study is that it empirically analyzed the factors that ESG management activities affect workers' jobs,. As a result, it was confirmed that workers were satisfied with their jobs by actively showing interest in social(S) activities and governance(G) activities among ESG management activities and participating in corporate management. In addition, workers sensitive to changes in the external environment can become satisfied with their jobs through self-efficacy when SMEs actively enhance corporate competitiveness, execute ESG management activities, and provide a fair organizational culture. Finally, this study suggests that there's a possibility of improving the competitiveness of SMEs through a virtuous cycle created by a change in perception of job conversion and a decrease in turnover.

• Journal of Korean Dental Hygiene Science
• /
• v.6 no.2
• /
• pp.129-139
• /
• 2023

Background: The elderly population aged 65 or older in Korea is expected to continue to increase to 18.4% in 2023, and to enter a super-aged society at 20.6% in 2025. In clinical practice, the elderly discrimination of dental hygienists may experience difficulties during dental hygiene treatment due to an increase in the number of elderly patients due to aging, which can lead to maladjustment to work and turnover, so education on the understanding of the elderly is essential for students in the Department of Dentistry, who are prospective dental hygienists. Accordingly, a study was conducted to prepare for a super-aged society by studying the relationship between elderly discrimination and the knowledge and attitudes of the elderly, and to change the curriculum of universities and develop programs related to the elderly. Method: 204 students enrolled in the Department of Dentistry in D area were analyzed using the SPSS/WIN 25.0 program. The subject's geriatric discrimination, knowledge about the elderly, and attitude toward the elderly were calculated as the mean and standard deviation. T-test and one-way ANOVA were performed to verify the difference in geriatric discrimination according to the general characteristics of the subject, with a Scheffe' test applied for post-hoc analysis. Correlation analysis was conducted on the subject's geriatric discrimination, knowledge about the elderly, and attitudes toward the elderly. Results: Geriatrics scored 2.03±0.36 out of 4. Knowledge about the elderly was categorized as follows: physical domain 0.57±0.15; social domain 0.36±0.17; and psychological domain 0.35±0.20. The attitude toward the elderly was 3.86±0.27. Knowledge of the elderly averaged 11.27±3.30 points out of 25. The question with the highest percentage of correct answers to knowledge about the elderly was 'physical strength tends to decrease with age', which was 93.1%. The attitude toward the elderly according to the general characteristics of the study subjects showed significant differences in gender (p=0.040), age (p=0.026), and life experience with grandparents (p=0.001). The elderly discrimination of the study subjects showed a negative correlation in both attitude and knowledge toward the elderly, and among the elderly discrimination, there was a high positive correlation with regard to emotional avoidance (r=.892, p<0.001). Conclusion: College students are the leading players in caring for the elderly and are directly affected by aging social problems. Therefore, it is considered necessary to apply various programs in the state, society, and educational institutions to avoid negative prejudices that lead to positive thinking and discrimination against the elderly.

• Journal of Korean Dental Hygiene Science
• /
• v.6 no.2
• /
• pp.51-64
• /
• 2023

Background: This study was conducted to determine the association with dual jobbing on dental hygienists' job satisfaction and to identify the factors that lead to dual jobs. Methods: This study was an online survey of 110 currently employed dental hygienists conducted during the month of May 2022. To determine job satisfaction, we used the 20-item Korea-Minnesota Satisfaction Questionnaire (K-MSQ). Survey questions related to dual job were adapted and supplemented from the dual job survey instrument for dental hygienists to identify intention to dual job and future intention to dual job. Descriptive statistics, independent t-test, ANOVA and Scheffe's post hoc analysis, and multiple logistic regression were performed. Results: The dual job rate and future dual job rate of the participants in this study were about 27% and 47%, respectively. The means for Intrinsic job satisfaction, Extrinsic job satisfaction, and job satisfaction were 3.44, 3.15, and 3.36, respectively. It was statistically significant that extrinsic job satisfaction increased with increasing position, and intrinsic job satisfaction, extrinsic job satisfaction, and job satisfaction increased with increasing salary. Those currently working dual jobs cited "self-actualization" as a reason for doing so, and those who intended to work dual jobs in the future cited "not being paid enough in their primary job" as a reason. We found that a one-unit increase in intrinsic job satisfaction and job satisfaction increases the odds of future intention to dual job by about 1.07 and 1.05 times, respectively (p<0.05). Conclusion: This study confirmed the influence of dental hygienists' job satisfaction on intention to dual job and future intention to dual job, and self-actualization was found to be the main factor. Therefore, the consideration of dual jobs in the future will affect the improvement of dental hygienists as professionals and the reduction of turnover through better working conditions.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.4
• /
• pp.610-618
• /
• 2015

The purpose of this study was to analyze differences in emotional labor strategies, burnout, and work engagement according to general characteristics of school foodservice employees as well as verify differential effects of two emotional labor strategies on burnout and work engagement. Our survey was administered to 400 school foodservice employees in Gyeongbuk from March 3 to April 25, 2014. A total of 358 completed questionnaires were returned, and 350 questionnaires were used for final analysis. For verification of mean differences, the mean scores for surface acting, deep acting, burnout, and work engagement were shown to be 2.38/5.00, 3.46, 2.67, and 3.41, respectively. The mean surface acting was significantly different according to cooking certification (P<0.001), turnover number (P<0.001), salary (P<0.001), and school level (P<0.01). The mean deep acting was significantly different according to educational background (P<0.001), cooking certification (P<0.001), employment status (P<0.001), salary (P<0.001), school level (P<0.01), and meal service time (P<0.05). The mean burnout was significantly different according to educational background (P<0.01), cooking certification (P<0.05), employment status (P<0.001), school level (P<0.001), and meal service time (P<0.001). The mean work engagement was significantly different according to cooking certification (P<0.001), employment satus (P<0.001), salary (P<0.001), school level (P<0.01), and meal service time (P<0.05). Verification of causal models found that surface acting and deep acting increased burnout and deep acting, respectively (research model). Additionally, surface acting did not influence work engagement, and deep acting did not influence burnout (alternative models). In other words, we identified that emotional labor strategies have differential influences on burnout and work engagement. Finally, implications and limitations of this study are discussed.

• Korean Security Journal
• /
• no.48
• /
• pp.9-33
• /
• 2016

The purpose of the present study was to find out cause-and-effect relationship between job requirements and job resources, with job burnout as a mediator variable, and the effects of these variables on organizational effectiveness. The population in the present study was private security guards employed by 13 private security companies in Seoul and Gyeonggi-do areas, and a survey was conducted on 500 security guards selected using purposive sampling technique. Out of 460 questionnaires distributed, 429 responses, excluding 31 outliers or insincere responses, were used for data analysis. For analysis, data were coded and entered into SPSS 18.0 and AMOS 18.0, which were used to analyze the data. Descriptive analyses were performed to find out sociodemographic characteristics of the respondents. The exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to test the validity of the measurement tool, and the Cronbach's Alpha coefficients were calculated to test the reliability. To find out the significance of relationships among variables, Pearson's correlation analysis was performed. Covariance Structure Analysis (CSA) was performed to test the relationship among latent factors of a model for job requirements, job resources, job burnout, and organizational effectiveness of the private security guards, and the fitness of the model analyzed with CSA was determined by the goodness-of-fit index ($x^2$, df, p, RMR, GFI, CFI, TLI, RMSEA). The level of significance was set at .05, and the following results were obtained. First, even though the effect of job requirements on job burnout was not statistically significant, it had a positive influence overall, and this result can be considered such that the higher the perception of job requirements by the member of the organization, the higher the perception of job burnout. Second, the influence of job resources on job burnout was negative, which can be considered that the higher the perception of job resources, the lower the perception of job burnout. Third, even though the influence of job requirements on organizational effectiveness was statistically nonsignificant, it had a negative influence overall, and this result can be considered that the higher the perception of job requirements, the lower the perception of organizational effectiveness. Fourth, job resources had a positive influence on organizational effectiveness, and it can be considered that the higher the perception of job resources, the higher the perception of organizational effectiveness. Fifth, the results of the analysis between job burnout and organizational effectiveness revealed that, even though the influence of job burnout on organizational effectiveness was statistically nonsignificant, it had partial negative influences on sublevels of organizational effectiveness, and this may suggest that the higher the perception of job burnout by the organization members, the lower the organizational effectiveness. Sixth, the analysis of mediating role in the relationship between job requirements and organizational effectiveness, job burnout was taking partial mediating role between job requirements and organizational effectiveness. These results suggest that reducing job burnout by managing job requirements, organizational effectiveness that leads to job satisfaction, organizational commitment, and turnover intention can be maximized. Seventh, the analysis of mediating role in the relationship among job requirements, job resources, and organizational effectiveness, job burnout was assuming a partial mediating role in the relationships among job requirements, job resources, and organizational effectiveness. These results suggest that organizational effectiveness can be maximized by either lowering job requirements or burnout management through reorganizing job resources.