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The purpose of this study is to explore how particle shape influences the screening, including screening efficiency per unit time, and the relationship between vibration parameters and screening efficiency per unit time in discrete element method (DEM) numerical simulations.

In this paper, a three-dimensional discrete element model of vibrating screen with composite vibration form of swing and translation was proposed to simulate the screening process. In total, 11 kinds of non-spherical particles whose shapes changed in a continuous regularity gradual process were established using a multi-sphere method. In the DEM simulations, vibration parameters, including vibration frequency, vibration amplitude and stroke angle, and swing parameters, including swing frequency and swing angle, were changed to perform parametric studies.

It shows that the effect of particle shape on screening efficiency is quantitative actually. However, the trends of different shape particles’ screening efficiency per unit time are mainly consistent.

Some simple particle shapes can be expected to be explored to do screening simulation studies reasonably with modification of the simulation data in DEM numerical simulations. That may improve the computational efficiency of numerical simulations and provide guidance to the study of the screening process.

As for vibrating screen, the separation of granular materials is a very complicated process, particularly the screening with a swing trace. To study the characteristics of stratification and penetration in the swing vibrating screen, a three-dimensional numerical model was developed to simulate the screening process.

The discrete element method (DEM) was used to perform the numerical simulation, and the kinetic model of the swing screening was established. The regions of stratification and penetration were defined, and the mathematical functions relating fine particle ratio of stratification and penetration to time were presented using the least squares method.

The results show that the low value of frequency (5 and 10 Hz) has a limited effect on the stratification, while the obvious effect can be found at high frequency. A low frequencies or small swing angles may enhance the particle penetration. By studying the vibration parameters affecting the stratification and penetration rate, it is found that the frequency has more influence than the swing angle.

The higher screening efficiency and processing capacity can be further obtained for the swing vibrating screen by comparing with the linear vibrating screen. These results reveal the fundamental characteristics of particle motion in the swing screening, which will provide reliable guidance for studying the design optimization of vibrating screen.

This study aims to examine the influence of task interdependence on team members’ Moqi in virtual teams in China. The authors also aim to identify virtual collaboration as a mediator and distributive justice climate as a moderator in this relationship.

The data were collected from a sample of 87 virtual teams (including 349 individuals) from various Chinese companies through a three-wave survey. Hierarchical regression analysis, path analysis, bootstrapping method and multiple validity tests were used to examine the research model.

In virtual teams in China, task interdependence has a significantly positive influence on team members’ Moqi; Virtual collaboration mediates the relationship between task interdependence and team members’ Moqi; The distributive justice climate positively moderates the relationship between task interdependence and virtual collaboration, as well as the indirect effect of virtual collaboration on the relationship between task interdependence and team members’ Moqi.

In virtual teams, leaders can facilitate team members’ Moqi by designing highly interdependent tasks, encouraging team members to engage in virtual collaboration and cultivating a climate of high attention distributive justice.

This is one of the first studies to pay to the Moqi among team members rather than supervisor-subordinate relationships and further examine how team members’ Moqi is predicted by task interdependence via the mediation of virtual collaboration with the distributive justice climate playing a moderating role.

Business process models, while primarily intended for process documentation, communication, and improvement, are often also used as input for developing process-oriented software systems (Ouyang et al., 2009). Ensuring correctness, handling complexity, and improving reusability and maintainability of business process models are important for all these goals. The purpose of this paper is to propose an aspect-oriented business process modeling and correctness controlling method based on Petri nets to satisfy these goals.

The aspect-oriented paradigm provides a proper mechanism to modularization, and thus reduces the complexity of models, and also improves reusability and maintainability. However, weaving aspects into base processes may bring in mistakes or errors. To ensure correctness of modeling, this paper presents a formal approach to modeling aspect-oriented business processes and a method to ensure modeling correctness. Petri net is used as the process modeling language and its analysis techniques are applied to analyze the correctness of modeling. Two types of correctness, specifically, aspect-aspect correctness and base-aspect correctness are analyzed. A real banking process model is studied systematically in the case study to evaluate the approach and the performance assessments are conducted to show the cost and effect of the approach.

Designing aspect-oriented business process models help organizations reusing the model elements to reduce redundancy of their model repository, improving their maintainability, and supporting them to adapt to the changes of business requirements with flexible modeling. It is important to stress that the correctness of business process modeling is important in ensuring the quality of the models, especially in the safety-critical business domains, such as financial business domain.

In this paper, separation of concerns is used to separate the cross-cutting activities and core activities in accordance with the different functions of these activities, and an approach to modeling aspect-oriented business processes is proposed. First, the cross-cutting activities are encapsulated as aspects, while core business activities are modeled as base processes. Then, according to the correctness requirements of business process models, based on the weaving mechanisms of aspect-oriented approach, weaving correctness is defined. Weaving correctness controlling methods between multi-aspects and between aspects and base processes are designed. Errors or mistakes of aspect-oriented business process modeling are prevented during the procedure of modeling to ensure error-free business process modeling.

The meshfree node-based smoothed point interpolation method (NS-PIM) is extended to the forward and inversion analysis of a high gravelly soil core rock-fill dam during construction periods.

As one member of the meshfree methods, the NS-PIM has the advantages of “softer” stiffness and adaptability to large deformations which is quite indispensable for the stability analysis of rock-fill dams. In this work, the present method contains a reconstruction procedure to deal with the existence or nonexistence of the construction layers. After verifying the validity of the NS-PIM method for nonlinear elastic model during construction period, the convergence features of the NS-PIM and FEM methods are further investigated with different mesh schemes. Furthermore, the NS-PIM and FEM methods are applied for the forward analysis of a high gravelly soil core rock-fill dam and the convergence features under complex stress conditions are also studied using the rock-fill dam model. Finally, the NS-PIM method is used to calculate the Duncan–Chang parameters of the deep overburden under the high gravelly soil core rock-fill dam based on the back-propagation neural network method.

The results show that: the NS-PIM solution for construction analysis still possesses the property of upper bound solution even under complex stress conditions and can provide comparatively more conservative results for safety evaluation. Furthermore, it can be used to evaluate the accuracy of results and mesh quality together with the FEM solution which has the property of lower bound solution; the inversion analysis in this work provides a set of material parameters for the deep overburden under high rock-fill dam during construction period and the calculated results show good agreement with the measured displacement values and it is feasible to apply the NS-PIM to the forward and inversion analysis of high rock-fill dams on deep overburden during construction periods.

In further study, the feasibility of three-dimensional problems, elastic–plastic problems, contact problems and multipoint inversion can still be probed in the NS-PIM solution for the forward and inversion analysis of high rock-fill dams on deep overburden.

This paper introduced a method for the forward and inversion analysis of high rock-fill dams during construction period using the NS-PIM solution. The property of upper bound solution ensures that the NS-PIM can provide more conservative results for safety evaluation. The inversion analysis in this work provides a set of material parameters for the deep overburden under high rock-fill dam during construction periods.

First, the analysis from forward to inversion for high rock-fill dams during construction period using the NS-PIM solution is accomplished in this work. A procedure dealing with the existence or nonexistence of the construction layers is also developed for the construction analysis. Second, it is confirmed in this work that the NS-PIM still possesses the property of upper bound solution even under complex stress conditions (the forward analysis of high rock-fill dams during construction period). Thus, more conservative results can be provided for safety evaluation. Furthermore, it can be used to evaluate the accuracy of results and mesh quality together with the FEM solution which has the property of lower bound solution. Third, the calculated material parameters of the deep overburden in this work can be used for further studies of the high rock-fill dam.

This paper aims to study the complex behavior of a dynamical system using fractional and fractal-fractional (FF) derivative operators. The non-classical derivatives are extremely useful for investigating the hidden behavior of the systems. The Atangana–Baleanu (AB) and Caputo–Fabrizio (CF) derivatives are considered for the fractional structure of the model. Further, to add more complexity, the authors have taken the system with a CF fractal-fractional derivative having an exponential kernel. The active control technique is also considered for chaos control.

The systems under consideration are solved numerically. The authors show the Adams-type predictor-corrector scheme for the AB model and the Adams–Bashforth scheme for the CF model. The convergence and stability results are given for the numerical scheme. A numerical scheme for the FF model is also presented. Further, an active control scheme is used for chaos control and synchronization of the systems.

Simulations of the obtained solutions are displayed via graphics. The proposed system exhibits a very complex phenomenon known as chaos. The importance of the fractional and fractal order can be seen in the presented graphics. Furthermore, chaos control and synchronization between two identical fractional-order systems are achieved.

This paper mentioned the complex behavior of a dynamical system with fractional and fractal-fractional operators. Chaos control and synchronization using active control are also described.

This paper aims to discuss the precise altitude and velocity tracking control of a hypersonic vehicle, a global adaptive neural backstepping controller was studied based on a disturbance observer (DOB).

The DOB combined with a radial basis function (RBF) neural network (NN) was used to estimate the disturbance terms that are generated by the flexible modes of the hypersonic vehicle system. A global adaptive neural method was introduced to approximate the unknown system dynamics, with robust control terms pulling the system transient states back into the neural approximation domain externally.

The globally uniformly ultimately bounded for all signals of a closed-loop system can be guaranteed by the proposed control algorithm. Additionally, the command filtered backstepping methods can avoid the explosion of the complexity problem caused by the backstepping design process. In addition, the effectiveness of the proposed controller can be verified by the simulation used in this study.

Normally lateral dynamics issue should be discussed in the process of control system designed, the lateral dynamics are not included in the nonlinear dynamic model of hypersonic vehicle used in this paper, merely the longitudinal flight dynamics are discussed in this paper.

The flexible states in rigid modes are considered as the disturbance of the system, which is estimated by structuring DOB with NN approximations. The compensating tracking error and prediction error are used in the update law of RBF NN weight. The differential explosions complexity derived from the backstepping procedure is dealt with by using command filters.

This study aims to examine the effect of regional discrimination on tourists’ unethical behavior intention and the mediating role of tourist anger. Furthermore, the study examines whether the impact of regional discrimination on tourist anger is moderated by tourist self-efficacy.

Three scenario experiments were conducted to test the research hypotheses.

The results indicated an indirect effect of regional discrimination on tourists’ unethical behavior intention via tourist anger. In addition, the findings showed that tourist self-efficacy would weaken the relationship between regional discrimination and tourist anger.

This study reveals tourists’ emotional and behavioral reactions to regional discrimination. Further research can examine the influence of regional discrimination from other theoretical lens and field experiments are encouraged.

This study enriches current knowledge on regional discrimination by developing an integral framework to explore tourists’ reactions toward regional discrimination.

The purpose of this paper is to review the application of digital holography in studies of the corrosion of metallic materials.

Digital holography is used for in situ observation of the dynamic processes at the electrode | electrolyte interface and on the electrode surface during the corrosion dissolution of metallic materials.

Digital holography is an effect method to in situ observe the corrosion processes, and it can provide a direct experimental foundation for studying the corrosion mechanism.

Even though there are several challenges, digital holography will play a significant role in studying corrosion processes.

Of the studies covering culinary tourism and traditional culture, Generation Z remains an underexplored group despite being the primary consumers of future tourism. Research into young consumers’ motivations is hoped to clarify, protect, and sustain Hong Kong Tong sui among this generation. As such, this study focuses on Generation Z to understand the types of novel experiences Tong sui can create for them, and it is worth exploring in depth the diet that young people are interested in from the perspective of traditional food.

Based on Creswell’s guidelines for quantitative research, we investigated the relationships among multiple elements of Hong Kong Tong sui and Generation Z tourists. A corresponding questionnaire was designed to gather information for statistical analysis and contains five sections. The first part solicited basic respondent information. Sections 2–5 presented several key terms (nostalgic emotion, food authenticity, FCV, and purchase intention) to frame the questionnaire in terms of our hypotheses. Items were scored on 7-point Likert-type scales for ease of processing in SPSS 26.0.

All hypotheses were supported, with nostalgia having the most significant influence on Generation Z’s purchase intentions. Besides, young generations are willing to buy traditional food when exposed to the restaurants or enterprises have nostalgic elements and inspire nostalgia in consumer. Generation Z’s thoughts about food authenticity notably played a more significant role than FCV in terms of the nostalgia of traditional food. In addition, food authenticity and FCV were found to indirectly mediate the relationship between nostalgic emotion and purchase intention.

Examining these types of campaigns geared toward Generation Z tourists to advertise traditional food has enriched this tactic’s applicability. The approach also constructs a foundation to scrutinize the appeal of traditional dishes among young consumer groups to potentially strengthen such food’s influence.

This study highlights the importance of leveraging nostalgia and understanding the emotional connection that Generation Z has with traditional cuisine. It suggests that enterprises can develop new products or revive traditional recipes that cater to the nostalgic preferences of Generation Z. Marketing innovations, such as using social media influencers, can also be employed to create awareness and generate interest in traditional food. Traditional food can contribute to tourist destinations' promotion and differentiate them from competitors, boosting the tourism and catering industries and creating employment opportunities.

The promotion and preservation of traditional food can contribute to the preservation of cultural identity and heritage. By engaging local communities in culinary initiatives and fostering community pride, traditional food tourism can strengthen the connection to cultural heritage and encourage the preservation of traditional culinary practices. This engagement can lead to sustainable development by promoting local traditions and ensuring the participation of the local community in tourism activities.

This study offers novel theoretical insights into traditional food consumption and food marketing, thus narrowing gaps in research on young consumers and traditional food. Results enrich the understanding of Generation Z’s intentions to purchase traditional food by highlighting tourists’ preferences. Guidelines are also provided for the operators on creating nostalgic campaigns that appeal to young generations.