• Journal of Service Research and Studies
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• v.13 no.4
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• pp.1-23
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• 2023

Tablet PCs are gaining increasing popularity in today's context, offering convenience in store operations. However, some customers may have complaints. From the perspective of shadow labor, customers may perceive using tablet PCs as additional tasks, implying that tasks have been transferred from service staff to customers themselves. Therefore, this study aims to investigate the causes of customers' perception of shadow labor when using tablet PCs (perceived difficulty of use and perceived compulsion to use) and how these perceptions can influence their intention to reuse tablet PC ordering services. Additionally, the study examines whether customers' perception of shadow labor is influenced by digital literacy and information overload and investigates the positive impact of benefits arising from using tablet PCs on their perception of shadow labor. This research conducted an online survey through the Chinese survey specialist website "Wenjuanxing," targeting customers who use tablet PCs to place orders in restaurants. After collecting a total of 376 valid data points, demographic characteristics, frequency analysis, reliability analysis, validity analysis, correlation analysis, and regression analysis were conducted using SPSS 24.0. The empirical results from the 376 respondents reveal that digital literacy and information overload affect the perception of shadow labor and also influence the intention to reuse tablet PC ordering services. Furthermore, benefits showed significant moderating effects on these relationships.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.33 no.6
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• pp.1099-1110
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• 2023

The recognition system of autonomous driving and robot navigation performs vision work such as object recognition, tracking, and lane detection after multi-sensor fusion to improve performance. Currently, research on a deep learning model based on the fusion of a camera and a lidar sensor is being actively conducted. However, deep learning models are vulnerable to adversarial attacks through modulation of input data. Attacks on the existing multi-sensor-based autonomous driving recognition system are focused on inducing obstacle detection by lowering the confidence score of the object recognition model.However, there is a limitation that an attack is possible only in the target model. In the case of attacks on the sensor fusion stage, errors in vision work after fusion can be cascaded, and this risk needs to be considered. In addition, an attack on LIDAR's point cloud data, which is difficult to judge visually, makes it difficult to determine whether it is an attack. In this study, image scaling-based camera-lidar We propose an attack method that reduces the accuracy of LCCNet, a fusion model (camera-LiDAR calibration model). The proposed method is to perform a scaling attack on the point of the input lidar. As a result of conducting an attack performance experiment by size with a scaling algorithm, an average of more than 77% of fusion errors were caused.

• Journal of Venture Innovation
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• v.4 no.2
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• pp.1-16
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• 2021

It can be said that it has various effects on the organization depending on the leadership of the boss, including the CEO, who is the main agent of management. In this study, Servant Leadership is the subject of research, and the concept of Servant Leadership is established as Servant Leadership, in which subordinates who are members of a corporate organization perceive their bosses in the course of performing their duties. In this study, we examined the impact of Servant leadership on job satisfaction and non-financial organizational performance, analyzed the impact of Servant leadership on subordinates, and analyzed the mediated effects of ethics in relation to Servant leadership and job performance. The subjects of this study conducted a survey of 300 workers at small and medium-sized enterprises nationwide from March 15 to April 20, 2021, and used 273 data as empirical analysis data. Data analysis uses the SPSS 24.0 and AMOS 24.0 Statistical Analysis programs. Research has shown that Servant leadership is affecting job satisfaction and non-financial organizational performance. These results are absolutely necessary for management practice in various ways, such as strengthening servant leadership, to enhance job satisfaction and non-financial organizational performance, so it is necessary to develop and implement a program to feel unity with the organization. Therefore, organizational leaders need to create new ideas and actions to suit their objectives. To do so, it suggests that it is important to create a horizontal organizational structure in which fresh views can be derived rather than a vertical organizational structure that follows only the command system.

• Journal of Korea Port Economic Association
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• v.39 no.3
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• pp.91-105
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• 2023

This paper identified the difference in perception of the consignment system between the freight company and the consigned vehicle owners, derived factors that urgently need to improve the difference in perception, and presented the basis for establishing a management model based on this. A management model based on the difference in perception of consigned borrowers was established, and research hypotheses were established to conduct reliability, validity, and confirmatory factor analysis, path analysis, and mediation effect verification. As a result of the analysis, out of 58 questions, 56 of the total 65 questions showed a difference in perception of the consignment system between trucking companies and consigned vehicle owners, and the questions were input as management model factors. As a result of conducting confirmatory factor analysis, path analysis, and mediating effect verification using only recognition data, 5 hypotheses were adopted, and it was analyzed that the factor had no mediating effect. It can be analyzed that the appropriateness of the compensation system affects the improvement of each other's relationship, and the improvement of each other's relationship leads to the improvement of transportation services. However, since the mediating effect was rejected because it was not significant, this effect should not be exaggerated.

• Pediatric Infection and Vaccine
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• v.31 no.1
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• pp.55-63
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• 2024

Purpose: A 2-dose varicella vaccination strategy has been introduced in many countries worldwide, aiming to increase vaccine effectiveness (VE) against varicella infection. In this network meta-analysis, we aimed to provide a comprehensive evaluation and an overall estimated effect of varicella vaccination strategies, via a Bayesian model. Methods: For each eligible study, we collected trial characteristics, such as: 1-dose vs. 2-dose, demographic characteristics, and outcomes of interest. For studies involving different doses, we aggregated the data for the same number of doses delivered into one arm. The preventive effect of 1-dose vs. 2-dose of varicella vaccine were evaluated in terms of the odds ratio (OR) and corresponding equal-tailed 95% confidence interval (95% CI). Results: A total of 903 studies were retrieved during our literature search, and 25 interventional or observational studies were selected for the Bayesian network meta-analysis. A total of 49,265 observed individuals were included in this network meta-analysis. Compared to the 0-dose control group, the OR of all varicella infections were 0.087 (95% CI, 0.046-0.164) and 0.310 (95% CI, 0.198-0.484) for 2-doses and one-dose, respectively, which corresponded to VE of 69.0% (95% CI, 51.6-81.2) and VE of 91.3% (95% CI, 83.6-95.4) for 1- and 2-doses, respectively. Conclusions: A 2-dose vaccine strategy was able to significantly reduce varicella burden. The effectiveness of 2-dose vaccination on reducing the risk of infection was demonstrated by sound statistical evidence, which highlights the public health need for a 2-dose vaccine recommendation.

• Journal of the Korean Geotechnical Society
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• v.40 no.3
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• pp.41-54
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• 2024

Regular monitoring plays a crucial role in ensuring the safety of geotechnical structures. Currently, nondestructive methods are employed to monitor such structures to minimize the impact, e.g., sensor-based accelerometers, displacement meters, image-based lasers, and drone imaging. These technologies can observe surface changes; however, they frequently suffer difficulties in terms of identifying changes in internal properties. To monitor changes in internal properties, in situ geotechnical investigations can be employed. A nondestructive test that can be used for this purpose is the spectral analysis of surface wave (SASW) test using geophones. The SASW test is a nondestructive method; however, due to the time required for data interpretation and the difficulty in analyzing the data, it is challenging to use the SASW test for monitoring applications that require frequent observations. However, it is possible to apply the first-step analysis, which yields the dispersion curve, for monitoring rather than the complete SASW analysis, which yields the shear wave velocity. Thus, this paper presents a fundamental study on the phase difference that derives the dispersion curve to utilize the SASW test for monitoring. The reliability of each phase difference interval is examined to determine the boundary to the subjected monitor. The study used phase difference data obtained using a geophone from a single-layered, homogeneous ground site to evaluate reliable boundaries. The findings of this study are expected to improve the utility of monitoring by identifying the ideal boundary for phase difference data.

• Journal of Navigation and Port Research
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• v.47 no.6
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• pp.350-357
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• 2023

Marine accidents frequently occur due to the unreasonable operation of ships excluded from ship departure control during marine special weather warnings within smooth water areas. Coastal wave buoys installed in smooth water areas are major reference indicators for ship departure control and can be seen as being directly connected to the safety of ships navigating smooth water areas and the coast. In this study, the location appropriateness of currently operating coastal wave buoys and additional installation in the smooth water areas were assessed by analyzing coastal marine accidents over the past 30 years (1991-2020), the main wind direction and wind speed of each major trading port, and the GICOMS ship track data in 2018. The study results showed that an additional coastal wave buoy should be installed at each of the major trading ports(Inchon Port, Pohang Port, Ulsan Port, and Busan Port) and that the location of the coastal wave buoy needs to be moved in the case of Busan Port. Based on various data analysis in this study, the suggestion for an additional installation and movement of the coastal wave buoy presented in this study is expected to contribute to improving the reliability of ship departure control and resolving safety blind spots.

• Journal of the Korean Society of Radiology
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• v.82 no.3
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• pp.613-623
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• 2021

Purpose To evaluate the MRI findings and clinical factors that are characteristic of patients who ultimately undergo surgery for medial epicondylitis. Materials and Methods Fifty-two consecutive patients who were diagnosed with medial epicondylitis and underwent an elbow MRI between March 2010 and December 2018 were included in this retrospective study. The patients' demographic information, clinical data, and MRI findings were evaluated. All variables were compared between the conservative treatment and surgical treatment groups. Logistic regression analyses were conducted to identify which factors were associated with surgical treatment. Results Common flexor tear (CFT) tear size showed a statistically significant difference in both the transverse and longitudinal planes (p < 0.001, p = 0.013). The CFT abnormality grade significantly differed in both the transverse and longitudinal planes (p = 0.022, p = 0.003). A significant difference was also found in the medial collateral ligament abnormality (p = 0.025). Logistic regression analyses showed that only the transverse diameter of the CFT tear size (odds ratio: 1.864; 95% confidence interval: 1.264-2.750) was correlated with surgical treatment. Conclusion Of patients diagnosed with medial epicondylitis, patients with a larger transverse CFT tear size tend to undergo surgical treatment ultimately.

• Information Systems Review
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• v.19 no.4
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• pp.43-62
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• 2017

This study investigates the effect of bonding and bridging social capital on the technological innovation performance in the Pangyo Techno Valley. In particular, we consider the information technology (IT) usage in industrial cluster as an antecedent of social capital. IT instigates the intra and extra communication and information sharing between employees, thereby promoting the formation of a network of various members. Results show that the IT usage factor positively affects both bridging and bonding social capital, but an evident difference exists among the effects of social capital on the technological innovation performance. In case of Pangyo industrial cluster, bridging social capital exerts significant effect on the technological innovation performance, whereas bonding social capital shows insignificance. Bridging social capital is composed of the interactions of various networks. Bonding social capital is based on the strong tie from trust and internal cooperation. Results are related with the characteristics of Pangyo Techno Valley, where various IT ventures need active communication and information sharing with other organizations for technological innovation performance.

• Journal of the Korean Society of Radiology
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• v.18 no.3
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• pp.239-248
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• 2024

Radiation therapy uses high energy, which can have side effects on the human body. Therefore, it is important to ensure that the appropriate dose is set for irradiation and to have confidence in the radiation produced by the generator. The EPR/Alanine dosimetry system is characterized by water equivalence, dose response linearity, and low fading, which makes it useful for quality control of radiation therapy equipment. In this study, we compared the signal and dose response curves of EPR/Alanine dosimetry by mass of alanine using 6 MV energy of a LINAC. An alanine dosimeter and EPR spectrometer from Burker, and a LINAC from Elekta, were used. A dose response curve and a 1st order regression equation were constructed from the irradiated dose and the EPR signal from the alanine dosimeter. We compared the signal magnitude and dose response curve with mass and checked the confidence through the measurement uncertainty of the dose response curve. As a result, it was found that the magnitude of the EPR signal increased by about 1.3 times at 64.5 mg, and the sensitivity of the dose response curve increased as the mass increased. The measurement uncertainty was evaluated to be between 5.84 % and 8.93 %. Through this study, it is expected that the EPR/alanine dosimetry system can be applied to the quality assurance and quality control of a LINAC.