• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.3
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• pp.279-286
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• 2019

In this study, an experimental study on the tensile properties of steel fiber-reinforced ultra high strength concrete(UHSC) with a standard compressive strength of 180MPa was performed. Steel fibers with a volume ratio of 1% were mixed to prepare direct tensile strength specimens and prism specimens for the three-point bending test. The fabricated specimens were set up in the middle section of the specimen to induce cracks, and the test was carried out according to each evaluation method. First, the stress-strain curves were analyzed by performing direct tensile strength tests to investigate the behavior characteristics of concrete after cracking. In addition, the load-CMOD curve was obtained through the three-point bending test, and the inverse analysis was performed to evaluate the stress-strain curve. Tensile behavior characteristics of the direct tensile test and the three-point bending test of the indirect test were similar. In addition, the tensile stress-strain curve modeling presented in the SC structural design guidelines was performed, and the comparative analysis of the measured and predicted values was performed. When the material reduction factor of 1.0 was applied, the predicted value was similar to the measured value up to the strain of 0.02, but when the material reduction factor of 0.8 was applied, the predicted value was close to the lower limit of the measured value. In addition, when the strain was greater than 0.02, the predicted value by SC structural design guideline to underestimated the measured value.

• The Journal of the Korea Contents Association
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• v.21 no.9
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• pp.431-445
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• 2021

The purpose of this study was to provide implications for social work practice by examining the influence of career barrier on smart-phone addiction through self-esteem and depression among out-of-school adolescents. Using data from the Panel Survey of School Dropouts conducted by the National Youth Policy Institute, this study examined the research questions by analyzing the direct and indirect influences of career barrier on smart-phone addiction with the PROCESS macro method. First, the results of this study showed that out-of-school adolescents' career barrier statistically significantly increased smart-phone addiction. Also, out-of-school adolescents' depression mediated the influence of career barrier on smart-phone addiction, but out-of-school adolescents' self-esteem did not mediate the influence. However, out-of-school adolescents' self-esteem and depression dual-mediated the influence of career barrier on smart-phone addiction. The level of career barrier decreased the level of self-esteem, and in turn increased the level of depression, and finally increased the level of smart-phone addiction. Based on the findings, practical strategies to address the smart-phone addiction of out-of-school adolescents were discussed.

• Korean Journal of Labor Studies
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• v.24 no.2
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• pp.247-291
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• 2018

This study investigates the employment structure and the social safety net experience of the subcontracting cleaning workers in Korea, who have been main targets of the labor outsourcing despite the necessity and permanence of their labour. This study specifically focuses on the fact that these subcontracting cleaning workers are mostly female and in their old age, and analyzes how the combination of their age, gender, and employment structure leads to the (mis)match with the Korean social security system. Case study with in-dept interview method has been conducted to the old-aged female subcontracting cleaning workers in Korea. The result of this study is as follows. It was the income insecurity that led them to (re)enter the labour market, and the cleaning work was the almost the only wage work they could do considering their age and gender. Cleaning workers are mostly employed in the subcontracting company, and thus their labour contracts depend on the business contract period between the original and subcontracting company. Consequently, their employment relationship is mostly insecure unless they are guaranteed employment succession through the collective agreement of trade union. Moreover, it has been discovered that the employment insecurity due to the indirect employment relationship led to the poor labour conditions, low wage, and the exclusion from the social safety net.

• Journal of Science and Technology Studies
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• v.19 no.2
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• pp.1-40
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• 2019

Built upon ethnographic method such as participant observation and in-depth interview, this study analyzes the material culture of electronic flower auctions at Yangjae Flower Market. From the viewpoint of Actor-Network Theory(ANT), this research examines how human actors like dealers and auctioneers interact with nonhuman actors such as market devices and these interactions form networks called "agencement." This research is focused on three main objectives: first, to study how the performance of auctions - i.e. the interactions between auctioneers and dealers - change in the wake of new market devices in the auctions; secondly, to look into what changes artifacts bring to the social relationships between auctioneers and dealers; lastly, to analyze the influence of new market devices on auction price in the market. The results of this research are as follows. First, the appearance of new market devices generates changes in the performance of auctions, which means the change of 'agencement' of flower auctions. Direct interactions between auctioneers and dealers turned into indirect interactions through new market devices. Moreover, the changes in the agencement brought changes to the identity of auctioneers and dealers. Secondly, the new agencement caused by the inflow of new market devices formed the trust between the devices and human actors, which gave rise to the trust in electronic auction and in counterpart actors as well. In addition, new market devices lowered direct interactions between auctioneers and dealers and thus made more equal relationships between the two than before. Lastly, market devices like trading screen reduced the leverage of auctioneers by providing dealers with bidding information previously possessed by auctioneers much openly and dealers were able to decide auction prices in more reasonable and dispassionate manner. Economic agency, power, trust, price, and information in the market is material and sensory.

• The Journal of the Korea Contents Association
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• v.21 no.6
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• pp.533-551
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• 2021

The purpose of this study was to analyze the influence of participative leadership on the job commitment of employees and to investigate the mediating effect of psychological empowerment and the moderating effect of issue leadership. A survey was conducted on employees working in various industries and analyzed using PROCESS macro (Hayes, 2013). The reliability and validity of measurement tools were reviewed through a preliminary survey, and the timing of measurement of independent variable and dependent variable was separated to overcome the common method bias. The results of the study are as follows. First, it has been confirmed that participative leadership has a positive influence on employee's job commitment. Second, participative leadership strengthened the psychological empowerment of employees, and through it, the indirect effect of improving the employee's job commitment was confirmed. Third, the moderating effect of issue leadership was confirmed in the relationship between participative leadership and psychological empowerment. Fourth, the moderated mediating effect was confirmed that the effect of participative leadership on job commitment through psychological empowerment is reinforced by issue leadership. This study contributes to the expansion of existing leadership research by empirically identifying the mechanism between participative leadership and employee's job commitment. Implications regarding the results of the study, limitations of the study, and future study tasks were discussed.

• The Journal of the Convergence on Culture Technology
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• v.8 no.4
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• pp.181-186
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• 2022

This study examines the effect of parenting stress on children's social competence in relation to parenting stress, children's social competence, and parents' self-esteem, The purpose of this study is to investigate whether parental self-esteem mediates the relationship between parenting stress and children's social competence. Frequency analysis and descriptive statistical analysis were performed on the data of the 7th year of 2014 Panel Study of Korean Children(PSKC), and Pearson's moment correlation coefficient was calculated for correlation analysis between variables. In addition, in order to verify the mediating effect of parental self-esteem in the relationship between parenting stress and the child's social competence, Process Macro Model 4 was applied to verify the mediating effect, The significance of the indirect effect was verified by the bootstrapping method. As a result of this study, first, the correlations between all latent variables showed significant correlations. Second, it was confirmed that mother and father self-esteem had a mediating effect in the effect of father and mother's stress on infants' social competence. These results suggest that in order to improve children's social competence, parents should be able to increase their self-esteem so that they can have faith and confidence in themselves and control their emotions well in parenting stressful situations.

• International Journal of Computer Science & Network Security
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• v.22 no.7
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• pp.245-251
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• 2022

Educational reform in Ukraine encourages the use of multimedia technologies in the training of specialists in Physical Education and Sports, which is one of the promising directions of education development. Therefore, the article specifies the content of the terms "innovation" and "technology". For modern society, the introduction of multimedia technologies in education is not so much theoretical as pragmatic, since under condition of globalization it concerns its historical development and prospects associated with the so-called "high technologies".Our goal is to improve the training of Physical Education and Sports specialists by means of multimedia technologies. All of innovative technologies can be divided into four groups, depending on the appropriate form of educational activity for their use. The development of multimedia technologies in the training of specialists in Physical Education and Sport at the present stage of education development should be carried out in accordance with the criteria of manufacturability, which are presented in the article: scientism, to rely on the theoretical provisions of pedagogical science and methods of teaching the discipline, socially recognized educational goals, prospects for modernization of Education; consistency, which provides for the interaction of parts and the whole in the organization of the study environment, as a result of which the physical development of the young generation is an integral entity; guarantee, that is, the error between the planned and obtained results should be minimal; manageability, that is, full management of the stages of work of the teacher and students, which make up the completed cycle of actions; mass participation, for the purpose of applying the technology does not depend on the physical training of students, the pedagogical skill of the teacher and the type of educational institutions. The article presents the theory and method of organizing sports events and circuses in the training of specialists in Physical Education and Sports by means of multimedia technologies. In order to increase the level of physical development of a person, physical fitness and the state of health of students, which has a clear trend to constant deterioration, it is necessary to instill love for sports, carry out high-quality training and organize sports events using multimedia technologies. In the process of sports activities, the participants' mental education is carried out. There are two types of communication here: direct and indirect, which are described in the article.In games and sports competitions, there are many opportunities for forming rules of collective behavior. The main issues of the organization of sports activities by means of multimedia technologies have been clarified. During sports competitions, the tasks presented in Physical Education and sports classes are improved, which ensure the improvement of physical and theoretical training of the individual. The pleasure of sports, bright, emotional spectacles, confirmed by multimedia technologies, arises from the participation of the viewer in them.

• Journal of the Korean Orthopaedic Association
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• v.55 no.2
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• pp.188-192
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• 2020

An indirect reduction through the bicipital groove and allogenic iliac tricortical bone graft was performed as a treatment for a large Hill-Sachs lesion with a rotator cuff tear in an acute traumatic shoulder joint dislocation in an elderly patient. Six months after surgery, the rotator cuff healing and bone union were confirmed. The patient also showed satisfactory clinical results with 95 points of the American Shoulder and Elbow Surgeons (ASES) shoulder score and active range of motion with 155° flexion, 120° abduction, and 70° external rotation and 30° internal rotation at 90° abduction. The surgical method can be considered for a large Hill-Sachs lesion with rotator cuff tear in an acute traumatic shoulder joint dislocation in elderly patients.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.5
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• pp.7-15
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• 2022

Since the direct and indirect damage caused by the fire in the underground utility tunnel will cause great damage to society as a whole, it is necessary to make efforts to prevent and control it in advance. The most of the fires that occur in cables are caused by short circuits, earth leakage, ignition due to over-current, overheating of conductor connections, and ignition due to sparks caused by breakdown of insulators. In order to find the cause of fire at an early stage due to the characteristics of the underground utility tunnel and to prevent disasters and safety accidents, we are constantly managing it with a detection system using image analysis and making efforts. Among them, a case of developing a fire detection system using CCTV-based deep learning image analysis technology has been reported. However, CCTV needs to be supplemented because there are blind spots. Therefore, we would like to develop a high-performance acoustic-based deep learning model that can prevent fire by detecting the spark sound before spark occurs. In this study, we propose a method that can collect sound in underground utility tunnel environments using microphone sensor through development and experiment of prototype module. After arranging an acoustic sensor in the underground utility tunnel with a lot of condensation, it verifies whether data can be collected in real time without malfunction.

• Korean Journal of Culture and Social Issue
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• v.28 no.2
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• pp.163-186
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• 2022

The study was conducted to reveal the influence of variables causing post-traumatic growth and suggest ways to utilize it in the counseling and clinical field. Data from 208 youths in Korea were collected and analyzed using the SPSS 25.0 and AMOS 26,0 statistic programs. This study took the perspective that post-traumatic growth was affected by the balanced- time-perspective and social-connectedness and tried to examine the influence and relation of the two variables. A frequency-analysis was performed to identify the demographic characteristics and the trends of the variables, and a Pearson's -correlation analysis was conducted to examine the relations between variables. A hierarchical- regression- analysis was performed to examine the influence of the major variables, And path-analysis was carried out to verify the research model, and the indirect effect was confirmed by using the bootstrapping method. First, religion, among all demographic variables, showed a significant effect on the post-traumatic growth. Second, the balanced-time-perspective and social-connectedness had a significant effect on post-traumatic growth. Third, the balanced time perspective influenced social-connectedness and through this process, the path explaining how post traumatic growth occurs was revealed. This suggests that the both balanced time perspective and social connectedness are important for inducing post- traumatic growth, and the utility of the variables in the counseling and clinical field.