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This review aims to give a critical view of the wheel/rail high frequency vibration-induced vibration fatigue in railway bogie.

Vibration fatigue of railway bogie arising from the wheel/rail high frequency vibration has become the main concern of railway operators. Previous reviews usually focused on the formation mechanism of wheel/rail high frequency vibration. This paper thus gives a critical review of the vibration fatigue of railway bogie owing to the short-pitch irregularities-induced high frequency vibration, including a brief introduction of short-pitch irregularities, associated high frequency vibration in railway bogie, typical vibration fatigue failure cases of railway bogie and methodologies used for the assessment of vibration fatigue and research gaps.

The results showed that the resulting excitation frequencies of short-pitch irregularity vary substantially due to different track types and formation mechanisms. The axle box-mounted components are much more vulnerable to vibration fatigue compared with other components. The wheel polygonal wear and rail corrugation-induced high frequency vibration is the main driving force of fatigue failure, and the fatigue crack usually initiates from the defect of the weld seam. Vibration spectrum for attachments of railway bogie defined in the standard underestimates the vibration level arising from the short-pitch irregularities. The current investigations on vibration fatigue mainly focus on the methods to improve the accuracy of fatigue damage assessment, and a systematical design method for vibration fatigue remains a huge gap to improve the survival probability when the rail vehicle is subjected to vibration fatigue.

The research can facilitate the development of a new methodology to improve the fatigue life of railway vehicles when subjected to wheel/rail high frequency vibration.

Previous research has analyzed the consequence of network stability; however, little is known about how partner type diversity influence network stability in R&D network. Based on knowledge-based view and social network theory, the purpose of this paper is to unravel the internal mechanisms between partner type diversity and network stability through the mediating role of knowledge recombination in R&D network.

The authors collected an unbalanced panel patent data set from information communication technology industry for the period 1994–2016. Then, the authors tested the different dimensions of partner type variety and its relevance in the R&D network and the mediating role of knowledge recombination through adopting the multiple linear regression.

Results indicate an inverted U-shaped relationship between partner type diversity (variety and relevance) and network stability, whereas knowledge recombination partially mediate these relationships.

From the perspective of R&D networks, this paper explores that there are the under-researched phenomena the antecedent of network stability through nodal attributes (i.e. partner type variety and partner type relevance). Moreover, this paper empirically examined the mediating role of knowledge recombination in the partner type diversity–network stability relationships. The novel perspective allows focal firm to recognize importance of nodal attributes, which are critical to fully excavate the potential capabilities of cooperating partners in R&D network.

By introducing the mass customization service mode into the cloud logistics environment, this paper studies the joint optimization of service provider selection and customer order decoupling point (CODP) positioning based on the mass customization service mode to provide customers with more diversified and personalized service content with lower total logistics service cost.

This paper addresses the general process of service composition optimization based on the mass customization mode in a cloud logistics service environment and constructs a joint decision model for service provider selection and CODP positioning. In the model, the two objective functions of minimum service cost and most satisfactory delivery time are considered, and the Pareto optimal solution of the model is obtained via the NSGA-II algorithm. Then, a numerical case is used to verify the superiority of the service composition scheme based on the mass customization mode over the general scheme and to verify the significant impact of the scale effect coefficient on the optimal CODP location.

(1) Under the cloud logistics mode, the implementation of the logistics service mode based on mass customization can not only reduce the total cost of logistics services by means of the scale effect of massive orders on the cloud platform but also make more efficient use of a large number of logistics service providers gathered on the cloud platform to provide customers with more customized and diversified service content. (2) The scale effect coefficient directly affects the total cost of logistics services and significantly affects the location of the CODP. Therefore, before implementing the mass customization logistics service mode, the most reasonable clustering of orders on the cloud logistics platform is very important for the follow-up service combination.

The originality of this paper includes two aspects. One is to introduce the mass customization mode in the cloud logistics service environment for the first time and summarize the operation process of implementing the mass customization mode in the cloud logistics environment. Second, in order to solve the joint decision optimization model of provider selection and CODP positioning, this paper designs a method for solving a mixed-integer nonlinear programming model using a multi-layer coding genetic algorithm.

This paper aims to study a neural network-based fault-tolerant controller to improve the tracking control performance of an unmanned autonomous helicopter with system uncertainty, external disturbances and sensor faults, using the prescribed performance method.

To ensure that the tracking error satisfies the prescribed performance, the authors adopt an error transformation function method. A control scheme based on the neural network and high-order disturbance observer is designed to guarantee the boundedness of the closed-loop system. A simulation is performed to prove the validity of the control scheme.

The developed adaptive fault-tolerant control method makes the system with sensor fault realize tracking control. The error transformation function method can effectively handle the prescribed performance requirements. Sensor fault can be regarded as a type of system uncertainty. The uncertainty can be approximated accurately using neural networks. A high-order disturbance observer can effectively suppress compound disturbances.

The tracking performance requirements of unmanned autonomous helicopter system are considered in the design of sensor fault-tolerant control. The inequality constraint that the output tracking error must satisfy is transformed into an unconstrained problem by introducing an error transformation function. The fault state of the velocity sensor is considered as the system uncertainty, and a neural network is used to approach the total uncertainty. Neural network estimation errors and external disturbances are treated as compound disturbances, and a high-order disturbance observer is constructed to compensate for them.

Brand storytelling is an effective marketing tool. However, when choosing whether to tell more or tell less, it remains unclear which of these two narrative styles is most effective. This study aims to examine whether blank-leaving(less) leads to favourable brand attitudes and compares its effects on consumers’ story immersion, to non-blank-leaving(more).

Two experiments were conducted to test the hypotheses. In Study 1, a single-factorial design was used with 252 participants assigned at random to one of two narrative conditions: blank-leaving or non-blank-leaving. Study 2 replicated Study 1 and investigated the moderating role of implicit mindsets.

The results show that a blank-leaving narrative style increases favourable brand attitudes. Consumers present deeper immersion in the brand story that uses blank-leaving, as compared to non-blank-leaving, leading to a more favourable brand attitude. Furthermore, this effect is stronger for individuals with growth mindsets.

Telling the brand story using a blank-leaving narrative style is more effective in catching consumers’ attention than non-blank-leaving. In particular, a blank-leaving narrative is a good approach for targeting consumers who have a growth mindset.

To the best of the authors’ knowledge, this research is the first to investigate and compare the effects of blank-leaving and non-blank-leaving narrative styles on brand attitudes in the context of storytelling marketing.

The purpose of this paper is to examine the alternative accounts produced by Green Earth Volunteers (GEV), a Chinese environmental non-governmental organisation, over a 10-year period in the context of their campaign to create visibilities about hydroelectric dam projects along the Chang Jiang.

Drawing on conceptions of the human–nature relationship, including those evident in ancient Chinese philosophy and mythology, and the Chinese way of viewing and resolving conflict, this paper offers an interpretive analysis of the alternative accounts of GEV in terms of their form and content.

In terms of their content, the alternative accounts reflect elements of interrelated thinking, being underpinned by a recognition of the relationship between humans and nature, which is evident in Confucianism, Taoism and ancient Chinese mythology. The strategies adopted by GEV are a non-confrontational but feasible way to promote their ecological beliefs in the Chinese context.

The study suggests that social and environmental accounting (SEA) in developing countries is steeped in local cultural and philosophical traditions that need to be considered and incorporated into the design of alternative accounts.

The study contributes to the very limited literature that offers qualitative analyses of SEA in developing countries.

Water jet propulsion is widely used in various military and civilian fields due to its advantages of simple structure and high propulsion efficiency. The process of mooring involves utilizing specially designed equipment to secure a ship at a designated berth. During the process of water jet propulsion, the single propeller operates within a complex and turbulent three-dimensional flow. Hence, studying the coupling between the water jet propeller and the hull is critical to comprehending the characteristics of the device and the distribution of the flow field in detail.

Firstly, we conducted computational fluid dynamics (CFD)-based self-propulsion calculations to evaluate the interaction between the hull and the propeller. We subsequently analyzed the propeller's performance and the forces acting on the hull to understand how the presence or absence of the hull influenced the water jet propeller. Finally, we performed calculations and analysis of the cavitation characteristics of the coupling between the hull and the water jet propeller, considering different rotational speeds and water depths at the bottom of the pool.

The study demonstrated that the presence of the hull boundary layer under the hull-propeller coupling condition led to reduced uniformity of propeller inlet flow and lower efficiency of the propulsion pump. However, it also increased the bias toward low-flow conditions. Additionally, increasing the impeller speed led to a gradual increase in the cavitation volume within the water jet propeller, resulting in a gradual decrease in the propeller's performance.

This research provides the technical support required for effective design and operation of water jet propulsion systems. This paper involves studying and analyzing the performance and flow field of the coupling between the hull and propeller under mooring conditions with a specified hull model.

Based on cognitive appraisal theory of stress, this study develops an integrated model to examine the double-edged sword effect and boundary conditions of the impact of organizational crisis on employee behavior.

This study collected 672 employees’ data through three stages of longitudinal follow-up. Hierarchical regression analysis and SPSS macro process were used to test the hypotheses.

The paper finds that organizational crisis induces unethical pro-organizational behavior through enhanced job insecurity and foster taking charge by stimulating career calling. Employee resilience negatively moderates the relationship between organizational crisis and job insecurity as well as the indirect effects of organizational crisis on unethical pro-organizational behavior through job insecurity. Conversely, it positively moderates the association between organizational crisis and career calling and the indirect effects on taking charge through career calling.

This study not only expands the research on the mechanisms of organizational crisis' effects on employees' behaviors but also provides practical guidance for corporate managers on how to respond to organizational crisis.

The following insights are available to organizations and managers: first, this study confirms that organizational crisis can be perceived as threatening stressors that create job insecurity, which in turn leads to pro-organizational unethical behavior. Therefore, managers in organizational crisis should focus on stress regulation and guidance, pay timely attention to changes in the mindset of employees to reduce job insecurity, and strictly prohibit unethical pro-organizational behavior. They should promptly calm and control the atmosphere of panic and anxiety in the organization, do a good job of coordinating the division of labor, reduce personnel conflicts and contradictions, create a good organizational climate and reduce employees' sense of stress and negative perceptions of organizational crisis, thus reducing job insecurity and being able to meet the challenges in a better state. Secondly, this study confirms that employees also perceive organizational crisis as challenges and develop career calling, which in turn inspires proactive change behaviors. This suggests that managers in organizational crisis should promote the positive perception of organizational crisis as challenge, stimulate the career calling of employees in organizational crisis and call on and encourage employees to actively adopt taking charge. Therefore, managers should promptly give employees work affirmation, rewards and punishments, enhance the sense of participation and intrinsic motivation of subordinates, improve self-efficacy and self-confidence levels, effectively reduce the negative perception of organizational crisis, awaken positive psychological energy within individuals, increase their sense of belonging to the organization and thus, increase employees' awareness of the positive challenges of organizational crisis, stimulate employees' career calling through positive and optimistic beneficial pressure drive them to lead the corresponding changes in the crisis. Finally, this study confirms that employees' own resilience can change the double-edged sword effect of organizational crisis. Employees with high resilience are more likely to see organizational crisis as challenge and are thus more likely to develop career calling and are more inclined to initiate change, while employees with low resilience are more likely to see organizational crisis as threat, are more negatively affected by them, develop greater job insecurity and are, thus, more inclined to commit unethical pro-organizational behaviors. This reflects the fact that organizations should constantly cultivate employees' resilience and enhance their cognitive toughness at the same time. For instance, the organization can regularly use promotional lectures and scenarios to help leaders and employees establish corporate ethics, strengthen moral beliefs and correctly understand the nature of unethical affinity behavior. Managers should encourage and advocate positive and correct behaviors such as overcoming difficulties, positive innovation and positive suggestions to promote the sustainable and healthy development of the organization.

The results of this study can increase the organization’s understanding of the negative effects of crisis, help the organization take measures to manage and guide the employees in organizational crisis, more effective and targeted functional changes within the organization, reduce stress damage and improve the efficiency and effectiveness of crisis management. It is also beneficial to improve competitiveness and foresight in the organization’s industry and enhance organizations and employees’ resilience.

This study explores the double-edged sword effect of organizational crisis on employees’ behavior from the perspective of the cognitive appraisal theory of stress, which theoretically opens up a new research perspective, enriches the research in the fields of organizational crisis and taking charge, pro-organizational unethical behavior relationship and practically provides theoretical guidance for enterprises and managers on how to effectively respond to organizational crisis from the employees, which is of great practical significance.

Auxetics metamaterials show high performance in their specific characteristics, while the absolute stiffness and strength are much weaker due to substantial porosity. This paper aims to propose a novel auxetic honeycomb structure manufactured using selective laser melting and study the enhanced mechanical performance when subjected to in-plane compression loading.

A novel composite structure was designed and fabricated on the basis of an arrowhead auxetic honeycomb and filled with polyurethane foam. The deformation mechanism and mechanical responses of the structure with different structural parameters were investigated experimentally and numerically. With the verified simulation models, the effects of parameters on compression strength and energy absorption characteristics were further discussed through parametric analysis.

A good agreement was achieved between the experimental and simulation results, showing an evidently enhanced compression strength and energy absorption capacity. The interaction between the auxetic honeycomb and foam reveals to exploit a reinforcement effect on the compression performance. The parametric analysis indicates that the composite with smaller included angel and higher foam density exhibits higher plateau stress and better specific energy absorption, while increasing strut thickness is undesirable for high energy absorption efficiency.

The results of this study served to demonstrate an enhanced mechanical performance for the foam filled auxetic honeycomb, which is expected to be exploited with applications in aerospace, automobile, civil engineering and protective devices. The findings of this study can provide numerical and experimental references for the design of structural parameters.

This study examines how the different attributes of authentic leadership influence trust and employee organization fit and how such influences differ by gender and the level of positions during the COVID-19 pandemic.

The study employed a survey to examine US employees' perceptions toward different attributes of authentic leadership during the COVID-19 pandemic.

The study showed that self-awareness, balanced processing and internalized moral perspective positively relate to trust in the employer, mediated through employee–organization fit. However, relational transparency has a backfiring effect, negatively related to trust through the mediation of employee–organization fit. Additionally, this study highlights the differences in gender and level of positions in reactions to authentic leadership.

This study contributes to the understanding of internal public relations in a turbulent crisis time by proposing a mediated model that explains the effects of authentic leadership on employees' trust through their fit with the organization. Additionally, it identified that gender and position level are important factors moderating such effects.