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This paper aims to develop a novel type of bionic underwater robot (BUR) with multi-flexible caudal fins. With the coordinate movement of multi-caudal fins, BUR will combine the undulation propulsion mode of carangiform fish and jet propulsion mode of jellyfish together organically. The use of Computational Fluid Dynamics (CFD) and experimental method helps to reveal the effect of caudal fin stiffness and motion parameters on its hydrodynamic forces.

First, the prototype of BUR was given by mimicking the shape and propulsion mechanism of both carangiform fish and jellyfish. Besides, the kinematics models in both undulation and jet propulsion modes were established. Then, the effects of caudal fin stiffness on its hydrodynamic forces were investigated based on the CFD method. Finally, an experimental set-up was developed to test and verify the effects of the caudal fin stiffness on its hydrodynamic forces under different caudal fin actuation frequency and amplitude.

The results of this paper demonstrate that BUR with multi-flexible caudal fins combines the hydrodynamic characteristics of undulation and jet propulsion modes. In addition, the caudal fin with medium stiffness can generate larger thrust force and reduce the reactive power.

This paper implies that robotic fish can be equipped with both undulation and jet propulsion modes to optimize the swimming performance in the future.

This paper provides a BUR with multi-propulsion modes, which has the merits of high propulsion efficiency, high acceleration performance and overcome the head shaken problem effectively.

Distribution and occurrence of aromatic compounds and elements in the coal gangue dump from Fengfeng Coal Mine 5 and their influences on the environments have been studied in this paper. The samples were taken from the coal gangue dump, coal waste water stream and soil surface samples. These samples were analyzed by organic and inorganic methods. The results indicate that the coal gangues contain abundant harmful substances like aromatic hydrocarbon compounds, sulfur and trace elements. These harmful substances have influenced around area. In the soil surface, they influence the environments at least 750 m far from the coal gangue dump. In the waste water stream, they influence the water quality at least 2500 m far from the coal gangue dump.

This chapter aims to contribute to the literature on sustainability in the public sector by discussing how human resource and human resource management can help to integrate environmental management into organizations and improve environmental performance. Public sector scholars have neglected the study of Green Human Resource Management (GHRM) until now. Nevertheless, implementing such practices could lead to positive outcomes regarding awareness of environmental issues, organizational reputation and attractiveness, job satisfaction and organizational performance. The authors discuss the relevance and the necessity of developing a field of research on GHRM in public organizations. Starting from a conceptual review of the main literature on GHRM, this chapter provided some directions for future research.

The relation between metal corrosion behavior and double-layer capacity remains unclear. This study aims to put forward a novel method to measure double-layer capacity.

A novel model based on generalized Frumkin–Butler–Volmer equation was put forward. Combining this model with potentiodynamic polarization test and electrochemical impedance spectroscopy, the structure of double-layer capacity can be characterized.

This study found that the corrosion rate of iron increased with NaCl solution concentration and temperature at the experimental range, but an essential difference existed. The capacity of the diffuse layer and Stern layer increased with temperature and decreased with NaCl solution concentration. The ratio of diffuse layer capacity and Stern layer capacity influences the corrosion rate directly, which can be regarded as one of the judging criteria for corrosion resistance of metal materials.

The convenient means of double-layer structure characterization is still blank. With this method, the corrosion behavior of metal materials can be further analyzed, especially in high-temperature and pressure environments.

Drawing on the self-cognitive theory, this study aims to propose a conceptual model that links customer mistreatment with different types of helping behaviors through the self-efficacy mechanism.

The empirical analysis made use of the original data of three hotels located in southern China. The authors tested the hypotheses with a three-wave survey of a sample of 430 frontline workers in 95 groups.

Customer mistreatment may reduce employees’ self-efficacy, which has both positive and negative effects depending on the type of helping. Moreover, the coworkers’ supporting climate buffered the influence of self-efficacy on autonomous and dependent helping.

The authors resolve the ambiguity surrounding customer mistreatment-helping and self-efficacy-helping relations. Thus, the authors extend the knowledge on the influence of customer mistreatment and self-efficacy on helping behaviors by establishing that both positive and negative effects may exist depending on the type of helping. Moreover, this study identifies the predictive role of self-efficacy in autonomous and dependent helping.

This study aims to determine whether smartphones create the best communication fit with a young audience.

To validate the hypotheses, a task-based laboratory study was conducted. And smartphone film and television (TV) film were provided in the laboratory. Young respondents were recruited in the classroom and brief introduction and film were broadcasted. After watching the film, levels of respondent’s emotional experience was measured via questionnaire.

The results indicate that when the text of the film matches the young audience’s schema, the young audience uses, mainly, imagery coding to interpret the text and achieve an emotional experience. Conversely, when the text and schema do not match, the young audience uses both proposition coding and imagery coding.

Based on the results found in this study, companies should use different texts to match the different schema of young audiences to ensure that audiences can process coding and enjoy emotional experiences when using smartphone.

Dual-coding theory is applied to determine which coding system the audience use to interpret the new-media text, such as smartphone films.

The purpose of this study is to collect and assess the evidence available on the effect of non nutritive sweeteners on appetite, weight and glycemic regulation. As a replacement for sugars, non-nutritive sweeteners (NNSs) are widely being used in different food products with the assumption that these would lower calorie intake and help to manage weight and blood sugar levels better. However, studies using animal models have reported that chronic exposure to NNSs leads to increased food consumption, weight gain and insulin resistance.

Evidence was acquired from systematic reviews or meta-analyses (2016–2021) of relevant clinical studies, especially randomized control trials using Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines.

The review showed NNSs exposure did not conclusively induce increased food intake or change in subjective appetite ratings. Appetite biomarkers like ghrelin, gastric inhibitory peptide, C-peptide levels and Peptide YY remained mostly unaffected by NNSs. Meta-analyses of human randomized control studies showed a reduced energy intake and body weight. No significant change was seen in blood glucose levels, post-prandial glycemic or insulin response after consumption of NNSs. Adequate evidence is not available to conclusively say that NNSs influence gut health at doses relevant to human use.

Most studies which are prospective cohort, observational and cross-sectional studies suggest that use of NNSs may promote obesity and metabolic syndrome in adults. Such studies are plagued by confounding variables and reverse causation. Mechanistic evidence is mostly based on in-vitro and in-vivo studies. The same causal pathways may not be operative or relevant in humans.

This review of available literature concludes that to achieve specific public health and clinical goals, the safe use of NNSs for the reduction of intakes of free sugars and energy should be explored. This would be possible by educating the consumer about energy compensation and understanding the nutritional content of artificially sweetened products in terms of calories coming from fat and complex carbohydrates used in the product.

This study was, thus, designed with the objective of examining the usefulness of NNSs in human population, especially with respect to insulin regulation, glycemic control and weight management. Well-designed randomized control trials which control for confounding variables are needed to generate high quality evidence.

The purpose of this study to investigate the organized porous network zinc (OPNZ) scaffolds. Their mechanical characteristics, surface roughness and fracture mechanism were assessed in relation to their structural properties. The prospects of fused deposition modeling (FDM) for printing metal scaffolds via rapid tooling have also been studied.

Zn scaffolds with different pore and strut sizes were manufactured via the rapid tooling method. This method is a multistep process that begins with the 3D printing of a polymer template. Later, a paraffin template was obtained from the prepared polymer template. Finally, this paraffin template was used to fabricate the Zn scaffold using microwave sintering. The characterization of prepared Zn samples involved structural characterization, microstructural study, surface roughness testing and compression testing. Moreover, based on the Gibson–Ashby model analysis, the model equations’ constant values were evaluated, which can help in predicting the mechanical properties of Zn scaffolds.

The scanning electron microscopy study confirmed that the fabricated sample pores were open and interconnected. The X-ray diffraction analysis revealed that the Zn scaffold contained hexagonal closed-packed Zn peaks related to the a-Zn phase, validating that scaffolds were free from contamination and impurity. The range for ultimate compressive strength, compressive modulus and plateau stresses for Zn samples were found to be 6.75–39 MPa, 0.14–3.51 GPa and 1.85–12.6 MPa by adjusting their porosity, which are comparable with the cancellous bones. The average roughness value for the Zn scaffolds was found to be 1.86 µm.

This research work can widen the scope for extrusion-based FDM printers for fabricating biocompatible and biodegradable metal Zn scaffolds. This study also revealed the effects of scaffold structural properties like porosity, pore and strut size effect on their mechanical characteristics in view of tissue engineering applications.

A numerical simulation of the test beam was carried out with Abaqus and compared with test data to ensure that the modeling method is accurate. An analysis of the effects of the angle between the U-hoop and horizontal direction, the pre-crack height, the pre-crack spacing, and the strength of the geopolymer adhesive on the cracking load and ultimate load of the reinforced beam is presented.

Load tests and finite element simulations were conducted on carbon fiber reinforced polymer-reinforced concrete beams bonded with geopolymer adhesive. The bond-slip effect of geopolymer adhesive was taken into account in the model. The flexural performances, the flexural load capacities, the deformation capacities, and the damage characteristics of the beams were observed, and the numerical simulation results were in good agreement with the experimental results. An analysis of parametric sensitivity was performed using finite element simulation to investigate the effects of different angles between U-hoop and horizontal direction, pre-crack heights, pre-crack spacing, and strength of geopolymer adhesive on cracking load and ultimate load.

Under the same conditions, the higher the height of the pre-crack, the lower the bearing capacity; increasing the pre-crack spacing can delay cracking, but reduce ultimate load. By increasing the strength of the geopolymer adhesive, the flexural resistance of the beam is improved, and crack development is also delayed; the angle between the u-hoop and horizontal direction does not affect the cracking of reinforced beams; a horizontal u-hoop has a better effect than an oblique u-hoop, and 60° is the ideal angle between the u-hoop and horizontal direction for better reinforcement.

According to the experimental study in this paper, Abaqus was used to simulate the strength of different angles between U-hoop and horizontal direction, pre-crack heights, pre-crack spacings, and geopolymer adhesives, and the angles' effects on the cracking load and load carrying capacity of test beams were discussed. Since no actual tests are required, the method is economical. This paper offers data support for the promotion and application of environmentally friendly reinforcement technology, contributes to environmental protection, and develops a new method for reinforcing reinforced concrete beams and a new concept for finite element simulations.

With the rapid development of e-commerce in China, the third-party payment system greatly improved the efficiency and volume of the entire trading market. The purpose of this paper is to put forward a suitable prediction model to analyse its development trend.

The authors analyse internet third-party payments in China, taking into account online payment transaction values coupled with an ARMA model and the fractional grey model (FGM). First, the rolling FGM model is applied in order to characterise the trends of the transaction volume. The influence of the initial value change on the FGM model is analysed. The optimisation mean absolute percentage error (MAPE) model is constructed to determine the optimal translational values, the corresponding optimal accumulation order and optimal inverse accumulation order.

This paper uses China’s recent third-party online payment data to quantify its development trend. The authors find the coupling model suitable for the development trend of third-party online payment transaction. The results show that the model is suitable to quantify its development trend of China’s recent third-party online payment.

Considering the complex influence factors that lead to the third-party online payment volume data of time-varying grey feature, this paper combines the FGM with ARMA model to describe the development of third-party payment mode.