• Geomechanics and Engineering
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• v.18 no.4
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• pp.417-426
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• 2019

Gangue filling in the goaf is an effective measure to control the surface subsidence. However, due to the obvious deformation of gangue compression, the filling effect deserves to be further studied. To this end, the deformation of coal gangue filling in the goaf is analyzed by theoretical analysis, large-scale crushed rock compression test, and field investigation. Through the compression test of crushed rock, the deformation behaviour characteristics and energy dissipation characteristics is obtained and analysed. The influencing factors of gangue filling and predicted amount of main deformation are summarized. Besides, the predicted equation and filling subsidence coefficients of gangue are obtained. The gangue filling effect was monitored by the movement observation of surface rock. Gangue filling can support the roof of the goaf, effectively control the surface subsidence with little influence on the ground villages. The premeter and equations of the main deformation in the gangue filling are verified, and the subsidence coefficient is further reduced by adding cemented material or fine sand. This paper provides a practical and theoretical reference for further development of gangue filling.

• Safety and Health at Work
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• v.10 no.2
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• pp.151-165
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• 2019

Background: Despite improvements in safety performance, the number and severity of mining-related injuries remain high and unacceptable, indicating that further reduction can be achieved. This study examines occupational accident statistics of the Ghanaian mining industry and identifies priority areas, warranting intervention measures and further investigations. Methods: A total of 202 fatal and nonfatal injury reports over a 10-year period were obtained from five mines and the Inspectorate Division of the Minerals Commission of Ghana, and they were analyzed. Results: Results of the analyses show that the involvement of mining equipment, the task being performed, the injury type, and the mechanism of injury remain as priorities. For instance, mining equipment was associated with 85% of all injuries and 90% of all fatalities, with mobile equipment, component/part, and hand tools being the leading equipment types. In addition, mechanics/repairmen, truck operators, and laborers were the most affected ones, and the most dangerous activities included maintenance, operating mobile equipment, and clean up/clearing. Conclusion: Results of this analysis will enable authorities of mines to develop targeted interventions to improve their safety performance. To improve the safety of the mines, further research and prevention efforts are recommended.

• Advances in nano research
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• v.13 no.2
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• pp.165-174
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• 2022

In the present study, a hybrid model of artificial neural network (ANN) and internet of things (IoT) is proposed to overcome the difficulties in deriving governing equations and numerical solutions of the dynamical behavior of the nano-systems. Nano-structures manifest size-dependent behavior in response to static and dynamic loadings. Nonlocal and length-scale parameters alongside with other geometrical, loading and material parameters are taken as input parameters of an ANN to observe the natural frequency and damping behavior of micro sensors made from nanocomposite material with piezoelectric layers. The behavior of a micro-beam is simulated using famous numerical methods in literature under base vibrations. The ANN was further trained to correlate the output vibrations to the base vibration. Afterwards, using IoT, the electrical potential conducted in the sensors are collected and converted to numerical data in an embedded mini-computer and transferred to a server for further calculations and decision by ANN. The ANN calculates the base vibration behavior with is crucial in mechanical systems. The speed and accuracy of the ANN in determining base excitation behavior are the strengths of this network which could be further employed by engineers and scientists.

• Clinics in Shoulder and Elbow
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• v.26 no.2
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• pp.191-204
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• 2023

Avascular necrosis (AVN) of the humeral head is a rare, yet detrimental complication. Left untreated, humeral head AVN frequently progresses to subchondral fracturing and articular collapse. Cases of late-stage humeral head AVN commonly require invasive procedures including humeral head resurfacing, hemiarthroplasty, and total shoulder arthroplasty (TSA) to improve clinical outcomes. However, in cases of early-stage AVN, core decompression of the humeral head is a viable and efficacious short-term treatment option for patients with pre-collapse AVN of the humeral head to improve clinical outcomes and prevent disease progression. Several techniques have been described, however, a percutaneous, arthroscopic-assisted technique may allow for accurate staging and concomitant treatment of intraarticular pathology during surgery, although further long-term clinical studies are necessary to assess its overall outcomes compared with standard techniques. Biologic adjunctive treatments, including synthetic bone grafting, autologous mesenchymal stem cell/bone marrow grafts, and bone allografts are viable options for reducing the progression of AVN to further collapse in the short term, although long-term follow-up with sufficient study power is lacking in current clinical studies. Further long-term outcome studies are required to determine the longevity of core decompression as a conservative measure for early-stage AVN of the humeral head.

• Journal of Korean Academy of Nursing
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• v.33 no.2
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• pp.265-274
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• 2003

Purpose: The purpose of this study is to investigate the role of social support in the experience of job stress among hospital nurses. Method: This study was carefully designed to overcome methodological shortcomings found in past research, and examined two organizational effectiveness variables(job satisfaction and organizational commitment) as outcome variables. The sample used in this study consisted of 602 nurses from 5 general hospitals. Data were collected with self-administered questionnaires and analyzed using hierarchical regression and LISREL technique. Result: It was found that: (a) three job stress variables(workload, role conflict and conflict with other medical staff) have negative effects on job satisfaction and organizational commitment; (b) social support have positive main effects on the two output variables; (c) the negative effects of job stress variables on job satisfaction and organizational commitment are not buffered by social support, and (d) social support mediates the effects of job stress on job satisfaction and organizational commitment, and the size of the mediating effects is small. Conclusion: Further research needs to be done to further refine this study.

• Korea Journal of Hospital Management
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• v.24 no.4
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• pp.43-56
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• 2019

Purpose: Importance of patient satisfaction related to patient-centeredness has been emphasized, and it is known to have effect on various health outcomes including health resource utilization. However, the effect of patient satisfaction has been discussed mostly in terms of hospital marketing in Korea. This study aims to examine the effect of patient satisfaction in patient-physician communication on healthcare utilization in a nationally representative adult population of South Korea. Method: Patient satisfaction with physician communication is assessed using 4 items in the 2011 Korea Health Panel Survey. Generalized linear regression analysis is conducted using 9,325 adults' healthcare utilization in 2012. Findings: Adjusting for the socio-demographic, economic factors, individual health status, health behaviors and healthcare utilization in 2011, more satisfied individuals, more likely to utilize the outpatient service, especially in clinical setting. Practical Implications: The study findings suggests that in context of South Korea healthcare system such as insufficient medical consultation time and the absence of health delivery system, patient satisfaction as a subjective healthcare quality indicator would have effect on the individual's outpatient visit. This study contributes to stimulate patient satisfaction research and discussion in South Korea to further explore its relationship with potential and various health related outcomes. Further implications of the study are discussed.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.6 no.2
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• pp.149-166
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• 2011

This study investigates how the job satisfaction of the recipients with working ability is transformed into employment under the recent trends. The objects of this research are 15-19 years old. I used the data of YP2007. This survey were analyzed F-test by using SPSS PC win 12.0. This result maintain the importance about the policy of the recipients with working ability : (1) its bridging gaps between theory and reality, (2) focus on the Job satisfaction of the recipients with working ability, (3) developing new recipients with working ability education program, (4) elaborating the study methods. In this paper I describe one line of research focused on the job satisfaction of the recipients with working ability in view of their professional life as it is currently developed and expressed. This study also requires further studies and this study will be supplemented.

• Journal of Engineering Education Research
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• v.15 no.5
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• pp.54-59
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• 2012

It is reported that the constructivistic learning method (CLM) enhances the understanding of the students in the learning process, especially in engineering classes. In CLM-based classes, the students can take the initiative in the learning process, which is called the student-centered model of the learning process. This is different from the traditional learning method based on the teacher-centered model, where a teacher plays the central role in the learning process of students. The authors have applied the method of CLM to one of the Engineering classes, namely production planning and inventory control (PPIC) class for undergraduate students. The PPIC class provides multimedia-based study materials and factory visits as well as regular lecture sections to cover the whole subject of inventory control theory and practice. In the review sessions, students are divided into several groups, and question-and-answer discussions were actively carried out among these groups under the support of the teacher as a facilitator. It was observed that the student engagement in the class was very active compared to the conventional lecture-based classes. As for further support of students understanding on the subject, simulation-based materials are also under study for the class. This paper presents the review of case study of CLM-based PPIC class and discusses the feasibility of simulation-based study materials for further improvement of the class.

• The Journal of Industrial Distribution & Business
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• v.5 no.1
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• pp.27-37
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• 2014

Purpose - This study analyzed the characteristics of social networking sites (SNSs) using related literatures, and researched the models discussed in precedent studies, to investigate the effects of SNS characteristics upon consumers'awareness, purchase intention, and recommendation. The purpose of the study was to investigate the use of SNSs as a marketing tool. Design, methodology, and approach - For an empirical analysis, the author distributed questionnaires online and offline, to verify the models and hypotheses. Respondents were persons aged 17 or older, who were frequent users of SNSs. The questionnaire survey was conducted for 11 days from September 30, 2013 to October 10, 2013. The author distributed 450 copies and received 430 responses. Finally, 412 copies were used for the analysis after excluding 18 copies having poor answers. Results - The findings about SNS users' behavior could be used as material in the future use of SNS as a marketing tool. Further, the study provided not only theories about SNS characteristics, but also variables and items that were verified during the empirical study. Conclusions - Further studies are needed to overcome the limitations and to establish various kinds of SNS marketing strategies in detail.

• Journal of the Korean Society of Safety
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• v.25 no.1
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• pp.62-64
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• 2010

Since 1990 in South Korea, the considerable concern for the safety of construction sights has been increased due to serious accidents. There have been numerous big improvements in preventing the accidents by strengthening legal enforcement and by continuing to emphasize the safety management. Further, the safety standards and criteria for temporary constructional work have been enacted and established in order to maintain safe work environments in temporary construction and structure settings. However, the death rate from fall accidents is still high in the temporary constructional and structural settings in comparison to other work places in construction. According to the analysis of accidents in the field of construction between 2000 and 2007, the death rate from fall accidents in the temporary constructional settings was highest. In addition, there have been more fall accidents in the work setting by small or medium construction enterprises rather than large enterprises due to the relative lack of the safety management. Thus, in this study, the analysis of the causes of fall accidents in the temporary constructional and structural settings between 2000 and 2007 was conducted. Moreover, a survey study was carried out in order to investigate further causes based on the analysis. Finally, this study was also conducted in order to provide basic information and knowledge about the prevention of future accidents.