• Microbiology and Biotechnology Letters
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• v.51 no.4
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• pp.403-415
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• 2023

This study aimed to isolate and identify L-(+)-lactic acid-producing bacteria from tree barks collected in Thailand and evaluate the potential strain as probiotics. Twelve strains were isolated and characterized phenotypically and genotypically. The strains exhibited a rod-shaped morphology, high-temperature tolerance, and the ability to ferment different sugars into lactic acid. Based on 16S rRNA gene analysis, all strains were identified as belonging to Weizmannia coagulans. Among the isolated strains, BKMTCR2-2 demonstrated exceptional lactic acid production, with 96.41% optical purity, 2.33 g/l of lactic acid production, 1.44 g/g of lactic acid yield (per gram of glucose consumption), and 0.0049 g/l/h of lactic acid productivity. This strain also displayed a wide range of pH tolerance, suggesting suitability for the human gastrointestinal tract and potential probiotic applications. The whole-genome sequence of BKMTCR2-2 was assembled using a hybridization approach that combined long and short reads. The genomic analysis confirmed its identification as W. coagulans and safety assessments revealed its non-pathogenic attribute compared to type strains and commercial probiotic strains. Furthermore, this strain exhibited resilience to acidic and bile conditions, along with the presence of potential probiotic-related genes and metabolic capabilities. These findings suggest that BKMTCR2-2 holds promise as a safe and effective probiotic strain with significant lactic acid production capabilities.

• Journal of the Korean Applied Science and Technology
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• v.41 no.2
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• pp.498-507
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• 2024

In the field of mental health care, long-term healing programs have gained widespread recognition for their effectiveness in promoting well-being. However, the efficacy of shorter-term interventions, such as 1-night 2-day programs, remains relatively understudied. The primary objective of this initiative is twofold: firstly, to enhance the overall well-being and resilience of participants, and secondly, to investigate the program's potential to ameliorate specific mental health indicators. These indicators include physical stress levels, autonomic nervous system health, brain activity, brain stress, and concentration. A 1-night 2-day mental health healing program was implemented for 560 civil servants from Jeollanam-do (mean age 47.87 yrs). The focus was on measuring changes through baseline assessments before participation and post-program assessments upon completion. Measurements included physical stress index, autonomic nervous system health, brain activity level, brain stress, and brain concentration. There was a significant decrease in physical stress, as well as a significant decrease in autonomic nervous system health (p<0.05). Although there was no significant difference in brain activity level, there was a tendency for brain activity level to stabilize in the high-frequency range. Additionally, a significant decrease in stress levels and an improvement in concentration were observed. Incorporating 1-night 2-day relaxation programs into our daily lives offers a holistic approach to caring for both our physical and mental health, providing essential moments of rejuvenation and self-care that contribute to overall well-being and fulfillment.

• Convergence Security Journal
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• v.23 no.4
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• pp.101-108
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• 2023

Military organizations have stricter ranks than other organizations, and the age of retirement is lower than that of civil servants in other fields. In a rapidly changing society with a high unemployment rate, it is very important to prepare psychological resources for self-management by improving individual positive strengths throughout life, including job search activities. Various studies are being attempted on positive psychological capital, employment, and productivity that emphasize the strength of positive resources and, from this point of view, contribute to productivity improvement. In this study, the effect of the positive psychological capital of discharged soldiers on their will to re-employment was investigated through questionnaires targeting actual veterans. As a result, it is found that hope, self-efficacy, resilience, and optimism influenced the will to re-employment in the order.

• Earthquakes and Structures
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• v.26 no.4
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• pp.261-267
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• 2024

With the increase in the exploitation depth of offshore oil and gas, it is possible to control the global buckling of deep-sea pipelines by the snake lay method. Previous studies mainly focused on the analysis of critical buckling force and critical temperature of pipelines under the snake-like laying method, and pipelines often suffer structural failure due to seismic disasters during operation. Therefore, seismic action is a necessary factor in the design and analysis of submarine pipelines. In this paper, the seismic action of steel pipes in the operation stage after global buckling has occurred under the active control method is analyzed. Firstly, we have established a simplified finite element model for the entire process cycle and found that this modeling method is accurate and efficient, solving the problem of difficult convergence of seismic wave and soil coupling in previous solid analysis, and improving the efficiency of calculations. Secondly, through parameter analysis, it was found that under seismic action, the pipe diameter mainly affects the stress amplitude of the pipeline. When the pipe wall thickness increases from 0.05 m to 0.09 m, the critical buckling force increases by 150%, and the maximum axial stress decreases by 56%. In the pipe soil interaction, the greater the soil viscosity, the greater the pipe soil interaction force, the greater the soil constraint on the pipeline, and the safer the pipeline. Finally, the pipeline failure determination formula was obtained through dimensionless analysis and verified, and it was found that the formula was accurate.

• Computers and Concrete
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• v.33 no.4
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• pp.341-348
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• 2024

Ultra-high-performance concrete (UHPC) has received remarkable attentions in civil infrastructure due to its unique mechanical characteristics and durability. UHPC gains increasingly dominant in essential structural elements, while its unique properties pose challenges for traditional inspection methods, as damage may not always manifest visibly on the surface. As such, the need for robust inspection techniques for detecting cracks in UHPC members has become imperative as traditional methods often fall short in providing comprehensive and timely evaluations. In the era of artificial intelligence, computer vision has gained considerable interest as a powerful tool to enhance infrastructure condition assessment with image and video data collected from sensors, cameras, and unmanned aerial vehicles. This paper presents a computer vision-based approach employing deep learning to detect cracks in UHPC beams, with the aim of addressing the inherent limitations of traditional inspection methods. This work leverages computer vision to discern intricate patterns and anomalies. Particularly, a convolutional neural network architecture employing transfer learning is adopted to identify the presence of cracks in the beams. The proposed approach is evaluated with image data collected from full-scale experiments conducted on UHPC beams subjected to flexural and shear loadings. The results of this study indicate the applicability of computer vision and deep learning as intelligent methods to detect major and minor cracks and recognize various damage mechanisms in UHPC members with better efficiency compared to conventional monitoring methods. Findings from this work pave the way for the development of autonomous infrastructure health monitoring and condition assessment, ensuring early detection in response to evolving structural challenges. By leveraging computer vision, this paper contributes to usher in a new era of effectiveness in autonomous crack detection, enhancing the resilience and sustainability of UHPC civil infrastructure.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.26 no.6
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• pp.97-115
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• 2023

Ecosystem services (ES) are the benefits that people obtain from ecosystems. Traditional ES assessment methods have focused on the supply of ES, using biophysical data. However, these methods often fail to capture the full value of ES, which is also determined by social and cultural factors. This study proposes a new approach to ES assessment that incorporates socio-cultural perspectives. The study was conducted in Seoul, South Korea. A survey was conducted of 1,805 residents of Seoul to assess their satisfaction with ecosystem services. Exploratory factor analysis was used to identify bundles of ES that were perceived as important by residents. A revised importance-satisfaction analysis was used to calculate the urgency level of each bundle. The results of the study showed that the 21 ES that were considered in the survey could be grouped into three bundles: urban green area-based, biodiversity-based, and resilience-based. The urgency level analysis showed that some bundles were more important than others, and that some bundles were more urgent than others. The findings of this study have several implications. First, they suggest that a socio-cultural approach to ES assessment can provide a more comprehensive and accurate assessment of ES. Second, they show that this approach can be used to identify areas where ES management is most needed. Third, they suggest that this approach could be used to inform ES management and policy decisions.

• Journal of Ecology and Environment
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• v.48 no.1
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• pp.74-84
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• 2024

Background: Despite many environmental problems, plastic waste emissions have been a significant surge during last few decades in the Republic of Korea. Furthermore, the emergence of the coronavirus disease 2019 (COVID-19) pandemic has lead to an increased use and disposal of plastic waste worldwide. This paper tried to present summarized data related to the production and disposal of plastics especially before and after the COVID-19 pandemic with environmental impacts of plastics. Also, review of plastic waste reduction policies and feasible policies to promote an act for a safe, sustainable environment are presented. Results: Plastics cause many environmental problems due to their non-degrading properties and have a huge direct and indirect impact on Ecosystems and Public Health. Microplastics need a lot of attention because their environmental effects are not yet fully identified. Despite plastic's significant impact on climate change, the impact is not yet widely known to the public. Since the COVID-19 pandemic, the use of plastic has surged and recycling has decreased due to the increase in delivery food and online shopping. Korea is introducing very active plastic and waste management policies, but it is necessary to implement more active policies by referring to the cases of other countries. Conclusions: In this article, we have scrutinized the evolution of plastic waste generation in the aftermath of the COVID-19 pandemic and delved into policy frameworks adopted by other nations, which South Korea can draw valuable lessons from. The formidable challenges posed by plastic waste, the remarkable shifts witnessed during the COVID-19 era, and the multifaceted response strategies elucidated in this paper all play a pivotal role in steering South Korea toward a sustainable future.

• Journal of Microbiology and Biotechnology
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• v.34 no.5
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• pp.1051-1058
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• 2024

This study investigated the impact of inulin (INL) on viability of L. plantarum D-2 (LPD2) by encapsulation through spray drying (SD) and its commercialization potential to alternative of conventional wall material maltodextrin (MD). LPD2, derived from sea tangle (Saccharina japonica) kimchi, is probiotics exhibiting significant attributes like cholesterol reduction, antioxidant properties, and resilience to acidic and bile environments. To enhance storage viability and stability of LPD2, encapsulation was applied by SD technology. The optimum encapsulation condition with MD was 10% MD concentration (MD10) and inlet temperature (96℃). The optimum concentration ratio of MD and INL was 7:3 (INL3) for alternative of MD with similar encapsulation yield and viability of LPD2. Viability of LPD2 with INL3 exhibited almost 8% higher than that with MD10 after 50 days storage at 25℃. Physicochemical characteristics of the encapsulated LPD2 (ELPD2) with MD10 and INL3 had no significant different between flowability and morphology. But, ELPD2 with INL3 had lower water solubility and higher water absorption resulting in extension of viability of LPD2 compared to that with MD10. The comprehensive study results showed that there was no significant difference in the encapsulation yield and physicochemical properties between ELPD2 with MD10 and INL3, except of water solubility index (WSI) and water absorption index (WAI). INL have the potential to substitute of MD as a commercial wall material with prebiotic functionality to enhance the viability of LPD2 by encapsulation.

• Journal of Information Science Theory and Practice
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• v.12 no.3
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• pp.14-35
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• 2024

This qualitative study explores cyberbullying among college students through Habermas's Theory of Communicative Action to examine the dissonance between online interactions and principles of rational discourse. Cyberbullying is a pervasive issue in digital communication that undermines logical, evidence-based conversation, fostering environments where misinformation, manipulation, and harm thrive. By analyzing case studies from three universities, the research identifies the characteristics, dynamics, and emotional impacts of cyberbullying on victims, highlighting the role of social media platforms in facilitating these negative interactions. The findings reveal significant challenges to authentic and equal online conversations, driven by power imbalances and a lack of genuine communication, leading to psychological distress, erosion of self-esteem, and changes in behavior among victims. The study underscores the potential of social media design and policy interventions to mitigate cyberbullying, emphasizing the need for educational programs, technological solutions, and community support to promote a safer, more respectful digital environment. Key themes include the dynamics of cyberbullying, the suppression of rational discourse, the psychological and emotional consequences of inauthentic communication, and strategies for resilience and recovery. The research contributes to understanding cyberbullying's complexities and suggests a multifaceted approach to addressing it, aligning with Habermas's ideal of communicative rationality to foster healthier online communities. Future research should further explore the intersection of technology design, user behavior, and regulatory policies to combat cyberbullying effectively.

• Korean Journal of Psychosomatic Medicine
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• v.28 no.1
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• pp.42-52
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• 2020

Objectives : Firefighters are always under stress due to their job environment, and they are likely to become psychologically vulnerable due to continuous exposure to traumatic events, which is a stressful situation that requires emergency standby at all times. The aims of this study were to examine mental health factors for each division of firefighters and to see the relationship between sleep and somatization symptoms among them. Methods : General characteristics and related inspections were conducted through self-reporting questionnaires for 1,264 firefighters working at Chungbuk fire stations. Several mental health factors were investigated by the Insomnia Severity Index, Severity of somatic symptoms, Impact of Event Scale, Perceived Stress Scale, Resilience Scale, Alcohol Dependent Screening Scale, and the Center for Epidemiologic Studies Depression Scale Depression Scale and Mini-International Neuropsychiatric Interview. Results : Among the mental health variables, the relationship between insomnia and somatization varies significantly depending on types of work. It was reported that the first aid team was significantly higher than the fire suppression and rescue team. Post-traumatic stress, depression and drinking also differ significantly depending on types of work. The first aid team reported more posttraumatic stress than the fire suppression team and more depressed mood than the rescue team. The administration part had more alcohol consumption than the fire suppression or first aid team. Resilience was significantly higher in the rescue team than the first aid team. No significant differences between the types of work about stress and suicide risks. Insomnia, stress, and post-traumatic stress were significant predictors of somatization among firefighters. Above all, insomnia was significant mental health variable affecting somatization. Conclusions : Various mental health factors were different according to the types of work in firefighters. The First aid team was more vulnerable to mental health variables such as insomnia and somatization than other divisions. Insomnia is the most important cause of somatization in firefighters, so it is recommended that they be treated for insomnia and to prepare institutional policies.