• Communications for Statistical Applications and Methods
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• v.28 no.2
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• pp.189-204
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• 2021

In a regression analysis, a single best model is usually selected among several candidate models. However, it is often useful to combine several candidate models to achieve better performance, especially, in the prediction viewpoint. Model combining methods such as stacking and Bayesian model averaging (BMA) have been suggested from the perspective of averaging candidate models. When the candidate models include a true model, it is expected that BMA generally gives better performance than stacking. On the other hand, when candidate models do not include the true model, it is known that stacking outperforms BMA. Since stacking and BMA approaches have different properties, it is difficult to determine which method is more appropriate under other situations. In particular, it is not easy to find research papers that compare stacking and BMA when regression model assumptions are violated. Therefore, in the paper, we compare the performance among model averaging methods as well as a single best model in the linear regression analysis when standard linear regression assumptions are violated. Simulations were conducted to compare model averaging methods with the linear regression when data include outliers and data do not include them. We also compared them when data include errors from a non-normal distribution. The model averaging methods were applied to the water pollution data, which have a strong multicollinearity among variables. Simulation studies showed that the stacking method tends to give better performance than BMA or standard linear regression analysis (including the stepwise selection method) in the sense of risks (see (3.1)) or prediction error (see (3.2)) when typical linear regression assumptions are violated.

• Nuclear Engineering and Technology
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• v.54 no.3
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• pp.909-916
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• 2022

To study the developments and variations of unsafe behaviors in nuclear power plants thus reduce the possibility of human-related accidents, this paper, based on the Game Theory, focused on the changes in benefits of the Department of Management, Operational and Emergency in a nuclear power plant, and established the expected revenue functions of these departments. Additionally, the preventive measures of unsafe behaviors in nuclear power plants were also presented in terms of these 3 departments. Results showed that the violations of the Operation Department (OD) and the Emergency Department (ED) were not only relevant with the factors such as their own risks, costs, and the responsibility-sharing due to accidents, but also affected by the safety investments from the Management Department (MD). Furthermore, results also showed that the accident-induced responsibility-sharing of both the OD and the ED would rise, if the MD increased the investments in safety. As a result, the probability of violation behaviors of these 3 departments would be attenuated consciously, which would reduce the unsafe behaviors in the nuclear power plants significantly.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.1
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• pp.51-58
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• 2023

Geofencing supports unmanned aerial vehicle (UAV) operation by defining stay-in and stay-out regions. National Aeronautics and Space Administration (NASA) has developed a prototype of the geofencing function, SAFEGUARD, which prevents stayout region violation by utilizing position estimates. Thus, SAFEGUARD depends on navigation system performance, and the safety risk associated with the navigation system uncertainty should be considered. This study presents a methodology to compute the safety risk assessment-based along-track position error bound under nominal and Global Navigation Satellite Systems (GNSS) failure conditions. A Kalman filter system using pseudorange measurements as well as pseudorange rate measurements is considered for determining the position uncertainty induced by velocity uncertainty. The worst case pseudorange and pseudorange rate fault-based position error bound under the GNSS failure condition are derived by applying a Receiver Autonomous Integrity Monitor (RAIM). Position error bound simulations are also conducted for different GNSS fault hypotheses and constellation conditions with a GNSS/INS integrated navigation system. The results show that the proposed along-track position error bounds depend on satellite geometries caused by UAV attitude change and are reduced to about 40% of those of the single constellation case when using the dual constellation.

• Journal of Chest Surgery
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• v.55 no.1
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• pp.85-87
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• 2022

Diaphragmatic hernias have been reported in 0.8%-1.6% of patients who experience blunt chest trauma. The hernia is assumed to form as a result of direct diaphragmatic violation or significant intraabdominal or intrathoracic pressure caused by the trauma. Some reports have described cases of delayed diaphragmatic hernia and subsequent stomach perforation that occurred a few days to several years after an accident. We report an extremely rare case of diaphragmatic herniation in which the process from initial blunt trauma to visceral organ perforation took only 2 days, without any evidence of herniation on the initial X-ray or computed tomography. Delayed diaphragmatic herniation and subsequent visceral organ perforation should not be missed during the period immediately after blunt chest trauma.

• Child Health Nursing Research
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• v.28 no.2
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• pp.91-102
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• 2022

Purpose: This study systematically analyzed cases in South Korea wherein nurses were prosecuted for involuntary manslaughter or injury due to professional negligence in pediatric care. Methods: We analyzed the precedents using the methodology of Hall and Wright (2008) and Austin (2010). Of the 618 cases retrieved from the Supreme Court Decisions Retrieval System in South Korea, we selected the 12 cases in which children were the victims and nurses were the defendants, using a case screening methodology. Results: The most frequent penalty was a fine, and newborns were the most frequent victims. The distribution of cases according to Austin's violation categories was: improper administration of medications (n=5), failure to monitor for and report deterioration (n=4), ineffective communication (n=4), failure to delegate responsibly (n=4), failure to know and follow facility policies and procedures (n=1), and improper use of equipment (n=1). Conclusion: To ensure the safety of children, nurses are required to teach and practice a high standard of care. Nursing education programs must improve nurses' awareness of their legal obligations. Nursing organizations and leaders should also work towards enacting effective nursing laws and ensuring that nurses are aware of their legal rights and responsibilities.

• Journal of Arbitration Studies
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• v.32 no.4
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• pp.33-51
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• 2022

According to the CISG, there are no special regulations for a reasonable period of time among the obligations to notify the contractual suitability of the goods. As a result, many disputes arise in 'notification within a reasonable period' despite being the most important treaty in practice in defining the obligation to notify nonconformities according to the suitability of goods for each case. Regarding the interpretation of Article 39 of the CISG, various judgments and arbitration decisions are being made in each country for a reasonable period to notify that the goods are not suitable for the contract.There are criticisms that these various views are too harsh on the buyer in the buyer's obligation to notify.It is important to create a unified principle because courts or arbitration agencies of the Contracting States of this Convention interpret in various ways the reasonable period of violation of the contract of goods stipulated in the Convention. Since most of the international commodity trading transactions around the world are regulated by the CISG, it is necessary to analyze and interpret cases in which this Convention is applied in court or arbitral tribunal of each country to derive a unified principle.

• Progress in Superconductivity
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• v.4 no.1
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• pp.19-26
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• 2002

We have earlier developed a 40-channel SQUID system. An important figure of merit of a MEG system is the localization error, within which the underlying current source can be localized. With this system, we investigated the localization error in terms of the standard deviation of the coordinates of the ECDs and the systematic error due to inadequate modeling. To do this, we made localization of single current dipoles from tangential components of auditory evoked fields. Equivalent current dipoles (ECD) at N1m peak were estimated based on a locally fitted spherical conductor model. In addition, we made skull phantom and simulation measurements to investigate the contribution of various errors to the localization error. It was found that the background noise was the main source of the errors that could explain the observed standard deviation. Further, the amount of systematic error, when modeling the head with a spherical conductor, was much less than the standard deviation due to the background noise. We also demonstrated the performance of the system by measuring the evoked fields to grammatical violation in sentence comprehension.

• Journal of the Korean Society of Clothing and Textiles
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• v.47 no.1
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• pp.152-170
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• 2023

Although ugliness had long been considered a negative form of beauty, it has become an independent aesthetic category. However, most previous art studies have focused on Rosenkranz's theory, making its application to contemporary fashion analysis challenging. Therefore, it is necessary to redefine ugliness. This study highlighted four modern ugliness categories from a modern perspective following the examination of the historical considerations of the ugliness concept, namely ugliness as a violation of taboo, ugliness as an unpleasant emotion, ugliness as a vulgar taste, and ugliness as an ethical flaw. From this perspective, SHOWstudios for fashion films were analyzed in the present study. The results of our analysis showed that ugliness in the film was related to socially sensitive subjects and stimulating images. Whereas costumes in the film were used as a tool to convey the subject and to enhance the visual effect of the image. In addition, clothing was identified as a core subject element of the video, particularly when considering ugliness as an ethical defect. This study provides further insights into contemporary fashion analysis, expanding the ugliness perspective, which had been limited to the specific perspectives of scholars.

• Journal of Wellbeing Management and Applied Psychology
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• v.5 no.4
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• pp.57-67
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• 2022

Purpose: The purpose of this study is to identify what research ethics issues are related to chemical incidents at the level of national disasters in Korea, and then to secure clear research ethics to prevent similar incidents from recurring. Research design, data and methodology: The study design was a case study of the humidifier disinfectant disaster in Korea. The humidifier disinfectant incident is a worldwide issue that has never occurred in the world. The main cause of the humidifier disinfectant incident that occurred only in Korea was the toxicity of the humidifier disinfectant contained in the humidifier spray. In this regard, research ethics will be derived through related laws and systems, research ethics status, incident damage and compensation, prosecution's investigation status, and the final precedent of the Supreme Court. Results: Although the lack of laws and systems of government departments related to humidifiers is important in the research results, the violation of ethics regulations by researchers during research experiments has become a decisive problem. Conclusions: In conclusion, the most important thing is that the research bioethics of researchers at the forefront should take precedence over any other values, especially during experiments and research related to public health.

• Journal of the Korean Society of Food Culture
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• v.23 no.2
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• pp.214-221
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• 2008

This study analyzed the survey results of 302 college students from a coed university in Korea. The following three research components were examined: relationships among different eating styles, violation behaviors after unwanted eating, and consumption behaviors for three different food types. The analysis results showed that restrained eating was positively related to emotional eating, but negatively related to external eating. And emotional and external eating displayed a positive relationship. Body shape dissatisfaction was a significant variable in explaining restrained eating behavior. After unwanted eating, the restrained eaters expressed more regrets and stronger determination to diet than the less restrained eaters. The emotional eaters and external eaters responded that they could not stop eating and performed binge eating behaviors when they failed their diet. With regard to food attitudes and eating styles, snacks were favorably related to emotional eating. Fast food attitudes were negatively associated with restrained eating. Preference was the only significant variable in explaining snack consumption frequency; however sex, preference, and restrained eating were significant for fast foods. Finally, vegetarian foods were explained by preference and sex.