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This paper presents a CFD analysis of three types of axial-flow magnesium-based automotive cooling fans. The numerical modeling was conducted for geometrically modified fan designs: one with no-beads, the second one with beads at the suction-side of the fan namely reverse-beads fan, and the third one with beads installed at the pressure-side of the fan namely forward-beads fan. The effect of geometric modifications of the fan blades on the volumetric flow rate, fan efficiency, and energy efficiency was investigated using Reynolds-averaged Navier-Stokes (RANS) equations following the multiple reference frame methodology. The fan with no-beads was fabricated using 3D printing technology and tested to measure the flow velocity. Subsequently, the fans with beads along with the no-beads fan designs were numerically analyzed. The volumetric flow rate, fan efficiency, and energy efficiency were quantified as a function of fan rotating speed. The results show that the reverse-beads fan produced a relatively more volumetric flow rate and energy-efficient compared to the forward-beads fan. Moreover, to further improve the performance of the reverse-beads fan, the location and size of the bead structure were varied along the radial direction of the fan blade. The optimized reverse-beads fan significantly improves the fan performance.

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.

Abstract Wood biomass char was used in a direct carbon fuel cell (DCFC) as an alternative fuel. This has many advantages because the DCFC is a high-efficiency system and wood biomass is a carbon-free and regenerative material. Several analytical techniques were employed to analyze the characteristics of three fuels, their effects on the cell’s performance, and the electrochemical reactions between the fuels and the electrolyte in the system. The morphological and textural characteristics of biomass char were similar to those of two types of coal used as fuels for a DCFC system in spite of the char’s significantly lower carbon content. A practical evaluation of the fuels used in the DCFC system was conducted, and when using the biomass char, the maximum power density was 60–70% that of the corresponding value for coal under the same conditions. The performance of the biomass char fuel was improved by stirring. The possibility of its practical application was also discussed.

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.

Abstract This study newly introduces a complementary cooperative algorithm considering generative adversarial network (GAN)-Conditional Latent Space (CLS) combined with bidirectional long short-term memory (BLSTM) for improved and efficient lithium-ion rechargeable battery state prediction. The GAN-CLS algorithm, which is an advanced method of GAN, can generate corresponding images from an input label description. Long short-term memory (LSTM) is a specific recurrent neural network (RNN) architecture that can predict sequences more accurately than conventional RNNs. In terms of battery state prediction, the combination of two methods (GAN-CLS and LSTM) surely provides more improved and efficient rechargeable battery state prediction in contrast to conventional state predictors. The procedure of this study is as follows. First, we propose methods to enhance the data from battery charge/discharge by converting prepared data to images; then, the GAN-CLS method is used to generate corresponding battery data from previous images. Subsequently, the generated data is used to train the BLSTM model. Finally, the trained model is used to predict the battery state. By various experiments and verification, it is concluded that the proposed study can be a good solution for rechargeable battery state prediction (reduction of the time cost 50 times in modeling and 20 times in train/test, provision of a more accurate prediction mean square error (MSE) smaller than 0.0025 and the average MSE less than 0.0013).

Exterior insulation finishing systems (EIFSs) can efficiently promote energy efficiency of buildings. In this study, an EIFS with high thermal efficiency is presented to improve the insulation behavior of building enclosure. Based on heat transfer analysis results, energy simulations of buildings with fire spread prevention structures were performed. Results revealed that heat flow through the wall increased by 10.3 % when using a metal rail to fix the insulation; in contrast, using non-combustible phenolic foam reduces heat flow by 37.4 %, satisfying the requirement for fire spread prevention structures. Additionally, the energy consumption decreased by 8.8 % when both mineral wool and phenolic foam were applied. Fire spread prevention structures are essential to improve the fire safety performance of buildings. This external insulation system efficiently promote energy saving in building; additionally, leveraging a phase change material to improve the thermal storage performance of the building can reduce energy consumption by up to 11.9 %.

AbstractIn Korea, seven species belonging to five genera of the family Bostrichidae have been recorded to date. To these seven species, we are adding four other species, namely, Psoa rubripennis sp. nov., Dinoderus speculifer Lesne, 1895, Heterobostrychus hamatipennis (Lesne, 1895), and Xylothrips pekinensis (Lesne, 1902: comb. nov.) to the Korean fauna. In addition, the genus Calophagus Lesne, 1902, is synonymized with the genus Xylothrips Lesne, 1901 (syn. nov.) and Xylothrips cathaicus Reichardt, 1966, is synonymized with X. pekinensis (Lesne, 1902: syn. nov.). We herein present the key to the identification of species of the Korean Bostrichidae family and three similar Xylothrips species in Asia using their photographs.

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.