• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.50 no.10
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• pp.709-716
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• 2022

In this paper the Gamma guidance law, which was used for IUS (Inertial Upper Stage), is applied for solid-motor guidance of a upper stage of a satellite launch vehicle. The RCS (Reaction Control System), which activates after burnout of the upper stage, is employed for the convergence of the guidance algorithm and compensation of velocity errors induced by the solid motor. The algorithm is also simplified by replacing the time-consuming numerical integration process to predict final vehicle states with Keplerian trajectories. The performance of the algorithm is evaluated by conducting 3-DOF computer simulations for off-nominal flight conditions. The numerical results show that Gamma guidance can reduce the orbit injection accuracy in comparison with that obtained by applying open-loop commands.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.22 no.5
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• pp.111-116
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• 2022

The causes of motor burnout include overload, phase loss, restraint, interlayer short circuit, winding ground fault, instantaneous overvoltage, and the rotor contacting the stator, leading to insulation breakdown, leading to breakdown or electrical accidents. Therefore, equipment failure causes not only loss due to cost required for equipment maintenance/repair, but also huge economic loss due to productivity decrease due to process stop because the process itself including the motor is stopped. The current level of technology for diagnosing motor failures uses vibration, heat, and power analysis methods, but there is a limit to analyzing the problems only after a considerable amount of time has passed according to the failure. Therefore, in this paper, a device and algorithm for measuring insulation resistance using DC AMP signal was applied to an industrial motor to solve this problem. And by following the insulation resistance state value, we propose a diagnosis of deterioration and failure of the motor that cannot be solved by the existing method.

• Journal of the Korea Safety Management & Science
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• v.24 no.4
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• pp.85-93
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• 2022

Today's customer service providers, who have the greatest impact on customer satisfaction, are experiencing severe stress and job burnout due to various causes. Unlike general companies, the corporation has a relatively high level of dissatisfaction with customer service since there is a large conflict between the provision of kindness and the reasonable handling of civil complaints according to laws and regulations. In order to analyze the environment of the NPS' customer service providers, 5.583 branch employees working at the National Pension Service and 407 call center employees were surveyed online using the questionnaire function of the Enterprise resource planning system. The contents of the survey consisted of a survey on customer-facing employees, the level of awareness of customer-facing workers protection measures, and opinions on improvement and supplementation related to customer-facing workers protection measures. As a result of the survey, 72.8% of the total respondents experienced grievance complaints, and the proportion of call center employees was even higher at 89.0%. In addition, both the branch and the call center had the largest share of complaints about obstruction of business, unreasonable demands, abusive language, and verbal abuse. More than 40% of call center employees in their 20s and 30s experienced the highest frequency of complaints 13 or more times a year. The most difficult thing in the process of responding to complaints was that both branch offices and call centers had insufficient psychological recovery time, lack of space, and lack of help from colleagues and superiors. Based on the survey analysis, it is suggested to establish a countermeasure through case analysis rather than the right to suspend work for civil complaints that cannot be handled, such as customized manuals and action strategies for the age group with high grievance complaints.

• Journal of the Korea Society of Computer and Information
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• v.27 no.8
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• pp.177-183
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• 2022

The purpose of this study is to examine the current status of the elderly welfare ordinances currently enacted and operated by local governments, analyze the actual conditions and problems of the contents, and suggest the direction of enactment and revision of the elderly welfare ordinances for actively responding to the demand for various welfare services for the elderly. To this end, the scope of the study was specified by ordinances in Gwangju Metropolitan City, five autonomous districts, Jeollanam-do, and 22 cities and counties, and the criteria for content analysis of the elderly welfare ordinance of these local governments were selected and compared and analyzed in the four major areas of elderly welfare: income and jobs, care, health, leisure activities, and social participation. According to the analysis results, the direction of enacting the ordinance is to secure financial resources for the elderly welfare budget, develop differentiated welfare policies for the elderly that reflect the characteristics of each local government, expand ordinances related to infectious diseases, enact ordinances for medical support for non-infectious diseases, and enact customized ordinances for the elderly living alone. Finally, the limitations on the research subject and analysis scope of this study and future research directions were presented.

• Asia Marketing Journal
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• v.17 no.2
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• pp.39-62
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• 2015

Relatively little studies have investigated employee recovery from internal service failure, especially from the employees' perspective. When handling customer complaints, employees must not only deal with legitimate customer demands after a service failure, such as providing an apology, rectifying the problem, and offering compensation, but they must also manage illegitimate dysfunctional customers, who may yell, threaten, and even physically harm the employee. These negative experiences can have strong effects, and employees can exhibit higher levels of stress such as burnout and emotional labor, which have been linked to dissatisfaction, tension and anxiety, reduced performance and effectiveness, and a greater propensity to leave the firm, ultimately leading to negative financial consequences for the firm. These conditions result in internal service failure and create the need to recover employees-in other words, internal service recovery. However, little research has examined this issue so far. The purpose of the current study, therefore, is to investigate the relationship between internal service recovery and employee outcomes. A pre-test, post-test between-subjects experimental design was developed. Participants were 166 part-time students who were working full-time. The average age of the participants was 36.74 years, and 57.50% of them were female. The average length of employment was 13 years. Participants were randomly assigned to one of four groups of approximately equal size. Three of the groups were subjected to an experimental situation involving an internal service failure, while one group was not exposed to failure, thereby acting as a control group. This study contributes to the service marketing literature in several ways. First, the study extends service failure and/or recovery research by examining recovery in an employee context. Second, this study attempts to measure internal service recovery and to empirically demonstrate its relationship to employee outcomes. Third, this investigation emphasizes the managerial importance of internal service recovery. For example, understanding the nature of the relationships between internal service recovery and its consequences can improve the effectiveness and efficiency of managers' resource allocation decisions.

• Progress in Superconductivity and Cryogenics
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• v.9 no.3
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• pp.37-40
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• 2007

Large critical current is one of the prerequisites for the design of superconducting electrical equipments with large power capacity. To enlarge the critical current. multiple parallel connection is inevitable. In multiple parallel superconducting coils. the difference in normal resistance of each shunt leads to unequal current distribution. which may yield burnout. Therefore. uniform current distribution is required for a stable operation of multiple parallel superconducting coils. In this paper, Rogowski coils were fabricated to measure each shunt current of a 4-parallel superconducting coil. Four Rogowski coils were installed at the copper bars, which are used as current leads in superconducting coils. As a result, linearity of the Rogowski coils was ascertained and coefficients of each coil, the ratio of voltage and current, were derived. The coefficients were compared with theoretically calculated values. Based on the coefficients, each shunt current was calculated in a 4-parallel superconducting coil, where uniform current. distribution was confirmed. This paper verified the feasibility of the fabricated Rogowski coils as well as operational stability of the 4-parallel superconducting coil in 77K.

• Safety and Health at Work
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• v.13 no.4
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• pp.394-400
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• 2022

Background: Impacts of exposure are generally monitored and recorded after injuries or illness occur. Yet, absence of conventional after-the-effect impacts (i.e., lagging indicators), tend to focus on physical health and injuries, and fail to inform if workers are not exposed to safety and health hazards. In contrast to lagging indicators, leading indicators are proactive, preventive, and predictive indexes that offer insights how effective safety and health. The present study is to validate an extended Voluntary Protection Programs (VPP) that consists of six leading indicators. Methods: Questionnaires were distributed to 13 organizations (response rate = 93.1%, 1,439 responses) in Taiwan. Cronbach α, multiple linear regression and canonical correlation were used to test the reliability of the extended Voluntary Protection Programs (VPP) which consists of six leading indicators (safe climate, transformational leadership, organizational justice, organizational support, hazard prevention and control, and training). Criteria-related validation strategy was applied to examine relationships of six leading indicators with six criteria (perceived health, burnout, depression, job satisfaction, job performance, and life satisfaction). Results: The results showed that the Cronbach's α of six leading indicators ranged from 0.87 to 0.92. The canonical correlation analysis indicated a positive correlation between the six leading indicators and criteria (1st canonical function: correlation = 0.647, square correlation = 0.419, p < 0.001). Conclusions: The present study validates the extended VPP framework that focuses on promoting safety and physical and mental health. Results further provides applications of the extended VPP framework to promote workers' safety and health.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.33 no.2
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• pp.206-214
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• 2023

Objectives: To determine the effect of the various type and number of shift work on sociopsychological stress in the university hospital nurses in Seoul, South Korea. Methods: Data was collected through a self-administered questionnaire that included general characteristics, the type and number of shift work in the past 4 weeks and the an sociopsychological stress based on PWI-SF. Logistic regression analysis was conducted to analyze the effect of shift work by types on sociopsychological stress of university hospital nurses using SAS 9.4 and it adjusted general characteristics by the additional models. Results: When the number of night shift work 3 or 4 compared to 0, sociopsychological stress was significantly high(OR=2.16, 95% CI=1.29-3.65). When 5 or more, it was higher(OR=2.39, 95% CI=1.55-3.72). Two continuous night shift work compared to 0 increased sociopsychological stress(OR=2.37, 95% CI=1.49-3.81) and 3 or more even more(OR=2.70, 95% CI=1.72-4.27). If the shift work type changes 14 or 15 times compare to below 11, sociopsychological stress is increased and even higher when 15 or more times but it's not significant after adjusting for covariates. Conclusions: It suggests that workplace with nurse expose to shift work should be on lookout for more than three night shift work, more than two continuous night shift work and more than 14 shift work change which can lead to burnout, absenteeism, depression and decreased productivity.

• Journal of Korean Academy of Rural Health Nursing
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• v.18 no.1
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• pp.27-39
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• 2023

Purpose: This study is a mixed methods research that was conducted to verify factors affecting the working experience of community-based long-term care hospital workers during the COVID-19 pandemic. Methods: The study was carried out from July 19 to November 3, 2021 for 340 nurses who worked at 10 long-term care hospitals located in G city. Results: As the study results, factors that affected job stress of the workers working at community-based long-term care hospitals included job satisfaction (β=-.27, p<.001), work demand (β=-.25, p<.001), fatigue (β=.19, p=.001), and cooperation and leadership (β=-.12, p=.049). It was found that the participants were struggling with physical and mental stress caused by the increased workload due to the preventative measures taken to stop the infection and spread of COVID-19. Despite this, they accepted their situation as necessary to overcome the pandemic and shared the quarantine guidelines of the government and community health centers while actively responding to prevent the spread of COVID-19 under the leadership of their supervisors. However, they were experiencing psychological and emotional burnout in the prolonged pandemic situation. Conclusion: It is considered necessary to help relieve their stress and provide psychological and mental support by adopting a policy to develop and apply comprehensive programs.

• Journal of Korean Academy of Rural Health Nursing
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• v.18 no.1
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• pp.57-71
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• 2023

Purpose: This study aims to provide primary data for policy alternatives by identifying the problem of the nursing workforce shortage. Methods: For quantitative data, 446 questionnaires were analyzed. The mean and standard deviation were used for content description. ANOVA analysis and Scheffe? test were used to compare the differences according to the hospital level. For qualitative data, 1:1 in-depth and group interviews were conducted for six participants. Results: The factors nurses prioritized when choosing a workplace were salary, commuting distance, and work-life balance. Clinical nurses cited low wages, heavy workloads, and burnout as the most considerable difficulties in performing their duties. Factors influencing nurse's turnover intention were low wages, unmanageable workload, and rotation to unwanted departments in that order. New nurses tend not to apply to small-medium-sized hospitals, experienced nurses in their 30s-40s leave hospitals due to childcare and shift work difficulties, and nurses in their 50s and older tend to move to nursing homes rather than acute hospital settings. Conclusion: In this study, wage and workload were mentioned as the most critical factors in nurses' workplace selection, job performance difficulties, and turnover intention, so it is necessary to pay attention to this aspect when improving treatment for nurses.