• Journal of Positioning, Navigation, and Timing
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• v.11 no.4
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• pp.351-360
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• 2022

Autonomous vehicles require precise knowledge of their position, velocity and orientation in all weather and traffic conditions in any time. And, these information is effectively used for path planning, perception, and control that are key factors for safety of vehicle driving. For this purpose, a high precision GNSS technology is widely adopted in autonomous vehicles as a core localization and navigation method. However, due to the lack of infrastructure as well as cost issue regarding GNSS correction data communication, only a few high precision GNSS technology will be available for future commercial autonomous vehicles. Recently, a high precision GNSS sensor that is based on a Broadcast-RTK system to dramatically reduce network maintenance cost by utilizing the existing broadcasting network is released. In this paper, we present the performance test result of the broadcast-RTK-based commercial high precision GNSS receiver to test the feasibility of the system for autonomous driving in Korea. Massive measurement campaigns covering of Korea region were performed, and the obtained measurements were analyzed in terms of ambiguity fixing rate, integer ambiguity loss recovery, time to retry ambiguity fixing, average correction information update rate as well as accuracy in comparison to other high precision systems.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.4
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• pp.673-685
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• 2021

This study aims to determine theoretically the best workers layoff/training strategy that entrepreneurs should apply to manage the COVID-19 crisis successfully. It also examines the impacts of the Saudi government's emergency measures on firm performance. The paper develops a theoretical framework in which the optimal control technics is applied to model the entrepreneur's hiring, layoff, and training behaviors. The results show that, during the current COVID-19 pandemic, the entrepreneur should first lay off the less productive workers to reduce labor costs. As more and more inefficient workers quit and profit increases, the entrepreneur starts expanding his activity and training workers. In the long run, only the training activity allows the firm efficiency to grow at a constant rate. This finding suggests that the key to long-run economic recovery in Saudi Arabia will rely on training, innovation, and adaptability to the new digital environment. The paper also shows that the Saudi government initiative of covering 60% of salaries for the small- and medium-sized entrepreneurs during the COVID-19 pandemic will enhance training activities in small- and medium-sized enterprises and improve their efficiency in both the short and long run. This policy will also prevent Saudi entrepreneurs from laying off half of their staff.

• Journal of English Language & Literature
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• v.59 no.4
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• pp.569-592
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• 2013

In Reservation Blues, Sherman Alexie examines how Indians can survive successfully in contemporary America, overcoming the tragic history of colonialists' violence and the resultant traumata. For Alexie, both reassembling the parts of the colonialist history through remembrance and testifying its unjustness play important roles not only in the decolonization process which probes the remnants and the negative effects of the colonialism deeply rooted in the lives of Indians but in the procedure of healing the political, cultural, and religious traumata. However, it should be noted that the ultimate aim of Alexie's decolonization does not lie in erasing every trace of the colonialism but in transforming its legacy into a story of survivance. The recovery of the tribal voices and the preservation of Indian traditions, blood, and cultures are essential in the survivance of Indians. Yet, Alexie's tribalism should not be viewed as an exclusive one. He knows well that it is neither possible nor desirable to maintain an exclusive tribalism based on blind adherence to a mythic or "pure" past. Exclusive tribalism is a cause for alarm in the contemporary world, a dynamic place where diverse cultures consistently change through collision, exchange, and negotiation. In Reservation Blues, Alexie stresses a spiritual and cultural flexibility that makes the cultural interpenetration possible as a key element of the meaningful survivance of contemporary American Indians.

• Journal of the Korean Society of Marine Environment & Safety
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• v.27 no.3
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• pp.429-438
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• 2021

The mandatory installation of the ECDIS (Electronic Chart Display and Information System) became an important navigational equipment for navigation officer. In addition, ECDIS is a key component of the ship's digitalization in conjunction with various navigational equipment. Meanwhile, cyber-attacks emerge as a new threat along with digitalization. Damage caused by cyber-attacks is also reported in the shipping sector, and IMO recommends that cybersecurity guidelines be developed and included in International Security Management (ISM). This study analyzed the cybersecurity hazards of ECDIS, where various navigational equipment are connected. To this end, Importance-Performance Analysis (IPA) was conducted on navigation officer using ECDIS. As a result, the development of technologies for cyber-attack detection and prevention should be priority. In addition, policies related to 'Hardware and Software upgrade', 'network access control', and 'data backup and recovery' were analyzed as contents to be maintained. This paper is significant in deriving risk factors from the perspective of ECDIS users and analyzing their priorities, and it is necessary to analyze various cyber-attacks that may occur on ships in the future.

• Journal of Distribution Science
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• v.20 no.2
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• pp.91-100
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• 2022

Purpose: The sports industry is a major form of leisure and entertainment, but the industry was tremendously affected by the Covid-19 pandemic. This study gives solutions for sports leisure retail stores to the effects of the Covid-19 crisis on consumers' sports products purchasing habits and then gives a logical conclusion regarding the findings of the topic. Research design, data and methodology: Scant research is available to feedback for owners and managers of sports leisure retail stores which elements could be considered to recover their business prior to the pandemic. For achieving this, this study investigated total 284 responses in the retail stores and conducted the ANOVA analysis to compare the level of intensity on the impact Covid 19 pandemic. Results: Our findings suggests that there was a statistically recognizable difference at the significance level of probability between the mean value of the impact index of Covid 19 pandemic and key recovery strategies, indicating the high degree of Covid 19 impact can be reducing by four solutions. Conclusions: Finally, this study concludes the specific entertainment elements that influence the purchasing behavior of consumers will ensure that the Sports industry deals with its internal problems first without necessarily looking at the outside factors such as the pandemic.

• Asia-Pacific Journal of Business
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• v.12 no.2
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• pp.25-37
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• 2021

Purpose - This study analyzes the situational relationship between the components of job crafting and innovation performance, and based on this, suggests practical alternatives to the effect of the control variables of organizational support. Design/methodology/approach - For this survey, 350 questionnaires were distributed to Korean SME workers from October 5, 2020 to March 20, 2021, and 230 questionnaires were collected. In order to check the validity of the questionnaire, the questionnaire judged to be inappropriate in response was excluded. The recovery rate was 65.7%, and the effectiveness of the questionnaire was 82%. Structural equation model and hierarchical regression analysis are used to analyze those data. Findings - First, job enhancement through job redesign as well as organizational support is a key task in order to expect innovative results from field members. Innovative performance is not created by individual jobs, but is created between jobs and jobs, tasks and tasks, teams and teams, and departments and departments. This is why it is worth paying attention not to the functional approach, but to the interconnection structure of the process. Research implications or Originality - In this study, it was analyzed that structural job resource increase and social job resource increase, which are components of job crafting, had a positive effect on innovation performance, and that challenging job will had no significant effect. Challenging work will itself does not negatively affect innovation performance. Combining the survey and interview, field members who make up the majority of respondents say that they do not lack the will to work. They claim that there is no channel or opportunity to express or practice a challenging will.

• Journal of Distribution Science
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• v.21 no.3
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• pp.47-60
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• 2023

Purpose: During and after Covid-19 pandemic, technology has emerged as a key factor in supporting the recovery of the economy and the rise of living standards. This study examines seven factors affecting the intention of food delivery apps usage, which include Performance Expectancy, Effort Expectancy, Social Influence, Hedonic Motivation, Price Value, and Habit, and how much influence they have on the customers' behavioral continuance of food delivery apps after Covid-19 Pandemic. Research methodology: This research is a quantitative descriptive research with 473 qualified respondents from 550 respondents collected. Besides using the UTAUT2 model (Venkatesh et al., 2012), Information Quality was added to give a better explanation for the consumers' intention towards continuance behavior using food delivery apps. The collected data is then processed using SPSS 22.0. Results: Habit factors and Information Quality factors have significant positive effects on promoting food delivery apps usage intention, which in turn influences continuance behavior. In addition, Habit factors and Information Quality factors together have an effect of 48.57% on Behavioral Intention. Conclusion: The result proves that positive habits and food information quality can increase the usage intention towards the behavioral continuance of consumers. Higher usage frequency can be improved by increasing these two factors.

• Microbiology and Biotechnology Letters
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• v.50 no.3
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• pp.430-435
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• 2022

The infectious bursal disease (IBD) is a highly contagious and acute poultry disease caused by Birnavirus. However, the vaccination is the only disease prevention, but several factors impeded vaccine development. Thus, a need for time to develop a novel technique for managing and treating respiratory diseases in poultry birds. Passive immunization is a hope and a possible alternative used in birds to meet this need. The current research attempted to produce egg yolk-based polyclonal antibodies against the IBD virus. The benefits of IgY include ease of extraction, lack of reaction with mammalian Fc receptors, and low production cost. Commercial layers were immunized with inactivated IBD virus subcutaneously according to the treatment regimen. The eggs were gathered daily, and yolk antibodies were extracted with the ammonium sulfate precipitation technique. The use of an indirect hemagglutination test demonstrated that IgY was IBD-specific. Until the end of the experiment, the specific IgY immunoglobulins did not lose activity when stored at 4℃. The specific immunoglobulin (IgY) treated challenged birds were demonstrated 92% recovery in comparison to the control group. The study implies that the IBDV specific IgY is an easily prepared and rich source of antibodies and offers an alternative therapeutic agent to cure IBD-infected birds.

• Biomedical Science Letters
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• v.28 no.4
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• pp.211-222
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• 2022

After more than two years of efforts to end the corona pandemic, a gradual recovery is starting in countries with high vaccination rates. Easing public health policies for a full-fledged post-corona era, such as lifting the mandatory use of outdoor mask and quarantine measures in entry have been considered in Korea. However, the continuous emergence of new variants of SARS-CoV-2 and limitations in vaccine efficacy still remain challenging. Fortunately, T cells and memory T cells, which are key components of adaptive immunity appear to contribute substantially in COVID-19 control. SARS-CoV-2 specific CD4⁺/CD8⁺ T cells are induced by natural infection or vaccination, and rapid induction and activation of T cells is mainly associated with viral clearance and attenuated clinical severity. In addition, T cell responses induced by recognition of a wide range of epitopes were minimally affected and conserved against the highly infectious subsets of omicron variants. Polyfunctional SARS-CoV-2 specific T cell memory including stem cell-like memory T cells were also developed in COVID-19 convalescent patients, suggesting long lasting protective T cell immunity. Thus, a robust T-cell immune response appears to serve as a reliable and long-term component of host protection in the context of reduced efficacy of humoral immunity and persistent mutations and/or immune escape.

• The Plant Pathology Journal
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• v.39 no.6
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• pp.566-574
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• 2023

The aim of this study was to investigate the regulation of lantipeptide production in Streptomyces globisporus SP6C4, which produces the novel antifungal lantipeptides conprimycin and grisin, and to identify the role of cytochrome P450 (P450) in tis regulation. To investigate the regulation of lantipeptide production, we created gene deletion mutants, including ΔP450, ΔtsrD, ΔlanM, ΔP450ΔtsrD, and ΔP450ΔlanM. These mutants were characterized in terms of their morphology, sporulation, attachment, and antifungal activity against Fusarium oxysporum. The gene deletion mutants showed distinct characteristics compared to the wild-type strain. Among them, the ΔP450ΔlanM double mutant exhibited a recovery of antifungal activity against F. oxysporum, indicating that P450 plays a significant role in regulating lantipeptide production in S. globisporus SP6C4. Our findings highlight the significant role of P450 in the regulation of lantipeptide production and morphological processes in S. globisporus. The results suggest a potential link between P450-mediated metabolic pathways and the regulation of growth and secondary metabolism in SP6C4, thereby highlighting P450 as a putative target for the development of new antifungal agents.