• Journal of Astronomy and Space Sciences
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• v.38 no.1
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• pp.65-82
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• 2021

For the vast majority of geostationary satellites currently in orbit, station keeping activities including orbit determination and maneuver planning and execution are ground-directed and dependent on the availability of ground-based satellite control personnel and facilities. However, a requirement linked to satellite autonomy and survivability in cases of interrupted ground support is often one of the stipulated provisions on the satellite platform design. It is especially important for a geostationary military-purposed satellite to remain within its designated orbital window, in order to provide reliable uninterrupted telecommunications services, in the absence of ground-based resources due to warfare or other disasters. In this paper we investigate factors affecting the robustness of a geostationary satellite's orbit in terms of the maximum duration the satellite's station keeping window can be maintained without ground intervention. By comparing simulations of orbit evolution, given different initial conditions and operations strategies, a variation of parameters study has been performed and we have analyzed which factors the duration is most sensitive to. This also provides valuable insights into which factors may be worth controlling by a military or civilian geostationary satellite operator. Our simulations show that the most beneficial factor for maximizing the time a satellite will remain in the station keeping window is the operational practice of pre-emptively loading East-West station keeping maneuvers for automatic execution on board the satellite should ground control capability be lost. The second most beneficial factor is using short station keeping maneuver cycle durations.

• Korean Journal of Organic Agriculture
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• v.29 no.3
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• pp.397-414
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• 2021

As the agricultural population continues to age, the shortage of labor is worsening. To respond to this, Machinery Operators, those who work on behalf of farmers, are on demand. This study examines the cases in Imsil, Sunchang, and Namwon in Jeollabuk-do, where such agencies are in action, and analyzes the elements of their success and customer satisfaction. A survey was circulated among the farmers who used these agricultural agencies, and a total of 180 responses were submitted. A multiple regression analysis was conducted to prove our thesis. The study shows that the agricultural assistance provided by the Machinery Operators did help in ameliorating the shortage of labor, and resulted in high customer satisfaction. In particular, it was analyzed that Assurance and responsiveness had a significant positive effect on satisfaction. In addition, satisfaction was analyzed to fully mediate between service quality and intention to reuse. This study provides further support for the need to expand the institution of Machinery Operators and to encourage agricultural agencies in order to address the shortage of labor in rural areas due to aging.

• International Journal of Computer Science & Network Security
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• v.21 no.11
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• pp.59-66
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• 2021

Many incidents of Carbon Monoxide (CO) poisoning have occurred because of people being unaware of its presence. There are currently available systems on the market, but they are limited to measuring CO in a certain area and lack vital functions. Additionally, little to no evidence-based information on their quality was available. Thus, a mobile application for detecting CO gas leakage in a vehicle and critical features to assist victims was developed. A usability and functionality test were conducted to determine the product's quality utilizing nine usability and six functionality task scenarios (n=5). Then, a System Usability Scale test was performed to obtain system satisfaction, usability, and learnability (n=50). The usability and functionality test shows that all the tasks given for both tests were 100% successful. The overall score obtained for SUS was 71.4, which indicates good acceptance and usability. Around 20% of respondents claimed that they would need the support of a technical person to be able to use the application and that they needed to learn a lot of things before they could use the application, which indicates the overall high learnability of the application. The result provides empirical evidence that the CO gas leakage detection mobile application is successful and receives good usability, functionality, acceptability, learnability, and satisfaction assessments. DetGas could benefit automobile owners and other stakeholders by mitigating the risk and harm associated with gas leaking that exceeds the safe limit.

• Journal of the Korean Society of Safety
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• v.37 no.5
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• pp.22-32
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• 2022

The domestic smart factory is being built and spread rapidly, mainly by mid-sized companies and large enterprises according to the government's active introduction and support policy. But these factories only promote production system and efficiency, so harmfulness and risk factors are not considered. Therefore, to derive harmful risk factors in terms of industrial safety for 12,983 government-supported smart factory workplaces from 2014 to 2019, industrial accident status analysis compared workplaces with automation facilities and government-supported workplaces with automation facilities. Also, to reduce risks associated with domestic smart factory processes, twenty government-supported workplaces with automation facilities underwent analysis, evaluating risks through a status survey using the process evaluation table. In addition, the status survey considered region, size, industry, construction level, and accident rate; the difference in risk according to the structure of the process was confirmed. Based on the smart factory process evaluation results, statistical analysis confirmed that serial, parallel, and hybrid structures pose different risk levels and that the risks of mixed structures are greater. Finally, safety control system application was presented for risk assessment and reduction in the smart factory process, reflecting the results of disaster analysis and actual condition investigation.

• The Journal of the Convergence on Culture Technology
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• v.8 no.2
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• pp.149-155
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• 2022

This is a descriptive study to investigate influencing factors of job satisfaction among nurses of comprehensive nursing care ward. The participants were 114 nurses working in comprehensive nursing care ward. Collected data were analyzed by using descriptive statistics, t-test, ANOVA, Pearson's correlation coefficients, and multiple linear regression analysis. The results showed that professional self-concept and teamwork were influencing factors of job satisfaction. Therefore, in order to improve job satisfaction of nurses in comprehensive nursing care ward, education and policy support to improve professional self-concept and teamwork. are needed.

• Journal of the Korea Safety Management & Science
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• v.24 no.3
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• pp.15-21
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• 2022

This study examined the certification effects of safety and health management system (SHMS) on the establishment level of SHMS and accident statistics in construction industry. This study obtained the establishment level of SHMS for 106 construction companies surveyed from our previous study. In addition, three major accident statistics (mortality rate, accidental mortality rate, and injury rate) for the companies were collected from the database in Korean Occupational Safety and Health Agency. The statistical analysis results revealed that the establishment level for SHMS certified companies was significantly higher than those for uncertified or certification preparing companies. Furthermore, SHMS certified companies showed significantly smaller accident statistics compared to uncertified or certification preparing companies. The results of this study support the positive effects of SHMS on reducing major industrial accidents in construction companies.

• International Journal of Advanced Culture Technology
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• v.10 no.3
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• pp.11-17
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• 2022

This study investigates income support, labor opportunities, and social capital by the demographic characteristics of the elderly who participate in the elderly job project, and especially the relationship between social and quality of life. We want to provide empirical data on how the elderly vocational business ultimately affects the lives of the elderly through the intervention of social capital. The intervention effect of social capital is as follows. Satisfaction with the elderly job project has a great impact on the quality of life, trust, network, and social participation. In particular, trust in the quality of life of the elderly had a great influence on the quality of life and was indirectly effective. In addition, the intervention of social participation between social capital was known, and the elderly job project increased social participation to improve the quality of life of the elderly. Therefore, it can be evaluated that the elderly job project has an important positive effect on the quality of life of the elderly, and the social capital formed through the elderly job project plays a role in directly or indirectly improving the quality of life of the elderly.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.110-116
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• 2022

The purpose of this study was to examine the effectiveness of gamification in nursing practice for undergraduate students, as well as to explore the use of gamification in nursing education. This study is a systematic review of RCTs evaluating the effectiveness of gamification in nursing practice for undergraduate students. A total of 7 articles were identified in a search of PubMed, Cochrane Library, and Embase, and the additional databases were CINAHL (in English) and RISS (in Korean) between September 28, 2022 to October 5, 2022. Themes related to the environment and personal behaviors between 2002 and 2021 were extracted. The intervention themes were blood transfusion, postoperative pediatric nursing, postoperative hemorrhage and brain trauma nursing, basic and advanced life support, disaster nursing, and neonatal resuscitation. The primary outcomes were knowledge in five studies, satisfaction in one study, and competency in one study. The secondary outcomes were satisfaction in three studies, confidence in two studies, performance in two studies, skills in two studies, and self-efficacy, motivation, professional attitude, cognition, gameful experience, and affective response in one study each. Therefore, gamification interventions can be utilized in nursing practice education instead of traditional teaching methods such as lectures and face-to-face clinical practice.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.316-321
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• 2022

Since 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly, infecting millions of people worldwide. On March 11, 2020, the World Health Organization declared coronavirus disease (COVID-19) a pandemic owing to the worldwide spread of SARS-CoV-2, which created an unprecedented burden on the global healthcare system. In this context, there are increasing concerns regarding co-infections with other respiratory viruses, such as the influenza virus. In this study, clinical data of patients infected with SARS-CoV-2 and other respiratory viruses were compared with patients infected with SARS-CoV-2 alone. The hematology and blood biochemistry results of 178 patients infected with SARS-CoV-2 , who were tested on admission, were retrospectively reviewed. In patients with SARS-CoV-2 and adenovirus co-infection, C-reactive protein levels were elevated on admission, whereas lactate dehydrogenase (LDH), prothrombin time, international normalized ratio, activated partial thromboplastin clotting time, and bilirubin values were all within the normal range. Moreover, patients with SARS-CoV-2 and human bocavirus co-infection had low LDH and high bilirubin levels on admission. These findings reveal the clinical features of respiratory virus and SARS-CoV-2 co-infections and support the development of appropriate approaches for treating patients with SARS-CoV-2 and other respiratory virus co-infections.

• International Journal of Advanced Culture Technology
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• v.10 no.4
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• pp.499-510
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• 2022

This study examines the reporting factors of crime against business in Korea and proposes a corresponding predictive model using machine learning. While many previous studies focused on the individual factors of theft victims, there is a lack of evidence on the reporting factors of crime against a business that serves the public good as opposed to those that protect private property. Therefore, we proposed a crime prevention model for the willingness factor of theft reporting in businesses. This study used data collected through the 2015 Commercial Crime Damage Survey conducted by the Korea Institute for Criminal Policy. It analyzed data from 834 businesses that had experienced theft during a 2016 crime investigation. The data showed a problem with unbalanced classes. To solve this problem, we jointly applied the Synthetic Minority Over Sampling Technique and the Tomek link techniques to the training data. Two prediction models were implemented. One was a statistical model using logistic regression and elastic net. The other involved a support vector machine model, tree-based machine learning models (e.g., random forest, extreme gradient boosting), and a stacking model. As a result, the features of theft price, invasion, and remedy, which are known to have significant effects on reporting theft offences, can be predicted as determinants of such offences in companies. Finally, we verified and compared the proposed predictive models using several popular metrics. Based on our evaluation of the importance of the features used in each model, we suggest a more accurate criterion for predicting var.