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Turbulence and pressure fluctuations are key elements in the bed protection design of hydraulic structures. However, their roles in a hydraulic jump are not yet fully understood, and the nature of their relationships are not conclusive. In order to better understand the relationships between pressure fluctuations and flow characteristics of a hydraulic jump downstream of a weir, detailed measurements of flow kinematics using the nonintrusive techniques of particle image velocimetry and bubble image velocimetry and pressure using voltage-type pressure gauges were carried out in this study. The physical modeling of the hydraulic jump was carried out using the simultaneous measurements of pressure and turbulent flow properties. The distributions of flow properties, such as water level and velocity, were assessed in each case. Based on the measurements, the correlations between the pressure fluctuations and the variables were investigated by coupling the statistical values of the variables at the same points. The analysis results show that the water level and turbulence intensity are the main factors influencing the pressure fluctuations in the hydraulic jump. Using these factors, an empirical formula and dimensionless numbers are proposed to show that the pressure fluctuations depend on the bubble flow behavior.

Recently, the Republic of Korea has experienced natural disasters, such as typhoons and heavy rainfall, as well as social accidents, such as large-scale accidents and infectious diseases, which are continuously occurring. Despite repeated disasters, problems such as inefficient early response and overlapping command systems occur continuously. In this study, we analyzed the characteristics of disaster management systems by foreign countries, and the status of the damages by disasters for the past 10 years in the Republic of Korea, to suggest possible measures to improve the Republic of Korea’s integrated disaster management system. When a disaster occurs in the Republic of Korea, the Si/Gun/Gu Disaster Safety Measure Headquarters, under the command of the local governments, become the responsible agencies for disaster response while the central government supervises and controls the overall disaster support and disaster management. To improve the current disaster management system, we propose to incorporate all disaster types rather than dividing them by type into natural disasters and social disasters. To improve the disaster response and disaster management system, we propose to restructure the current administrative organization, revise the disaster-related laws, and overcome problems, such as inter-ministerial interconnectivity and overlapping regulation.

In today’s increasingly competitive coffee industry, the point of running a good coffee shop is no longer to run a coffee and beverage shop simply, but to focus on the quality of service and the value that customers feel as a result. Previous studies have mainly discussed the customer satisfaction and behavioral intention of restaurants, while few studies have explored the influencing factors of customer satisfaction and behavioral intention of chain coffee shops. Given that the perceived service quality theory and DINESERV model can effectively predict customer satisfaction and behavioral intention, this study took 385 consumers in the first Starbucks Reserve flagship store in China as survey objects. SmartPLS 3.0 software was used to explore the relationship among respondents’ perceived service quality, customer perceived value, satisfaction, and behavioral intention. The results show that service quality has a partially significant positive effect on perceived value. Perceived service quality and customers’ perceived value both have significant positive effects on satisfaction. Customers’ satisfaction has a significant positive effect on their behavioral intention. These results indicate that enterprises should strengthen the emotional bond between consumers and enterprises and improve the reliability, assurance, and empathy of perceived service quality to create a better emotional resonance between consumers and the Starbucks brand to improve customer satisfaction. At the same time, it should also promote the symbolic perceived value of Chinese consumers to Starbucks to realize the sustainable development of coffee-shop operation and consumer repurchase. This study expands the research on the service quality, perceived value, and behavioral intention of coffee chain enterprises in the context of non-habitual coffee-drinking countries. Moreover, it provides case support for the operation and research of regional cultural consumption habits of international catering chain enterprises.

In an era of environmental crisis, the world is at a perilous moment. The fight between sustainability and economical choice has been a contentious matter and the world is facing environmental uncertainties today. The main purpose of the present study is to prepare an integrated exploration of the development of consciousness in all business categories. This study also focuses on the indispensable roles and impact of top management in merging the commitment and abilities to environmental leadership and thus, adds a contemporary insight into how businesses, economic stakeholders, government authorities, and the general human sphere can mitigate the runaway menace of environmental issues. Finally, the current authors conclude that the environment is the supernatural force that is making life a possibility on the planet. Therefore, every human operation should be regulated by the approaches mentioned in this study and efforts made through the strategic principles and theories of leadership.

In recent years, sustainability concerns have gained increasing attention among countries and stakeholders worldwide. Towards the transition to sustainable rural development, the rural web framework (RWF) has become a consistent tool. Indicators from the RWF have been used to explore sustainable rural development for decision-making tasks, which improves the social, economic, and environmental performance of rural regions. However, the application of the RWF in studies is on the decline. Furthermore, there is a lack of literature reviews on the importance of the RWF and its relationship with different facets of sustainable development. We conducted a systematic literature review (SLR) (a) to explore how studies have used the RWF in the context of sustainable development and (b) to identify areas for further research. This study found that the RWF has mostly been used in developed countries, with fewer applications in developing countries. We suggest that there should be increased application of the RWF, particularly in developing countries, to broaden the rural web–sustainable development discourse and its relevance. This paper presents several areas where the indicators of the RWF can be applied to illustrate their relevance for policy decisions towards the achievement of the sustainable development goals (SDGs).

This study investigated bio-based plastic cushioning materials foamed through water phase-change characteristics using the natural by-product wheat bran. Experiments were carried out while increasing the wheat bran content from 20% to 70% in a blended composite material of polypropylene (PP) and wheat bran (WB). From the experimental results, we were able to prepare a bio-based plastic cushion that contained a high amount of natural materials, with a bran content of over 50%. This indicates the possibility of meeting the criteria for biodegradable plastics, as well as bio-based plastics. In this study, by inducing a foaming ratio of 95% or more, a volume-expansion ratio from 16 times to over 62 times was achieved. In addition, the optimal mixing condition for inducing a high-expansion foam was when the mixing ratio of PP and WB was 50/50, and the water content of the foaming agent was 25 parts per hundred resin. Finally, dynamic cushioning characteristics of PP50/WB50 composite foam prepared in this study and Polystyrene (PS) bead based commercial products were compared. The composite foam of this study showed comparable values, confirming commercialization possibility.

This study introduces a novel methodology to calculate the carbon dioxide (CO2) emission reduction related to residual emissions, calculating the CO2 emission reduction through a 2 MW (40 tCO2/day) carbon capture and utilization (CCU) plant installed at a 500 MW coal-fired power plant in operation, to evaluate the accuracy, maintainability, and reliability of the quantified reduction. By applying the developed methodology to calculate the CO2 emission reduction, the established amount of CO2 reduction in the mineral carbonation was evaluated through recorded measurement and monitoring data of the 2 MW CCU plant at the operating coal-fired plant. To validate the reduction, the accuracy, reproducibility, consistency, and maintainability of the reduction should be secured, and based on these qualifications, it is necessary to evaluate the contribution rate of nationally determined contributions (NDCs) in each country. This fundamental study establishes the concept of CCU CO2 reduction and quantifies the reduction to obtain the validation of each country for the reduction. The established concept of the CCU in this study can also be applied to other CCU systems to calculate the reduction, thereby providing an opportunity for CCU technology to contribute to the NDCs in each country and invigorate the technology.