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Since many global path planning algorithms cannot achieve the planned path with both safety and economy, this study aims to propose a path planning method for unmanned vehicles with a controllable distance from obstacles.

First, combining satellite image and the Voronoi field algorithm (VFA) generates rasterized environmental information and establishes navigation area boundary. Second, establishing a hazard function associated with navigation area boundary improves the evaluation function of the A^* algorithm and uses the improved A^* algorithm for global path planning. Finally, to reduce the number of redundant nodes in the planned path and smooth the path, node optimization and gradient descent method (GDM) are used. Then, a continuous smooth path that meets the actual navigation requirements of unmanned vehicle is obtained.

The simulation experiment proved that the proposed global path planning method can realize the control of the distance between the planned path and the obstacle by setting different navigation area boundaries. The node reduction rate is between 33.52% and 73.15%, and the smoothness meets the navigation requirements. This method is reasonable and effective in the global path planning process of unmanned vehicle and can provide reference to unmanned vehicles’ autonomous obstacle avoidance decision-making.

This study establishes navigation area boundary for the environment based on the VFA and uses the improved A* algorithm to generate a navigation path that takes into account both safety and economy. This study also proposes a method to solve the redundancy of grid environment path nodes and large-angle steering and to smooth the path to improve the applicability of the proposed global path planning method. The proposed global path planning method solves the requirements of path safety and smoothness.

Competition among higher education institutions has pushed universities to expand their competitive advantages. Based on the assumption that the core functions of universities are academic, understanding the teaching–learning process with the help of student evaluation of teaching (SET) would seem to be a logical solution in increasing competitiveness. The paper aims to discuss these issues.

The current paper presents a narrative literature review examining how SETs work within the concept of service marketing, focusing specifically on the search, experience, and credence qualities of the provider. A review of the various factors that affect the collection of SETs is also included.

Relevant findings show the influence of students’ prior expectations on SET ratings. Therefore, teachers are advised to establish a psychological contract with the students at the start of the semester. Such an agreement should be negotiated, setting out the potential benefits of undertaking the course and a clear definition of acceptable performance within the class. Moreover, connections should be made between courses and subjects in order to provide an overall view of the entire program together with future career pathways.

Given the complex factors affecting SETs and the antecedents involved, there appears to be no single perfect tool to adequately reflect what is happening in the classroom. As different SETs may be needed for different courses and subjects, options such as faculty self-evaluation and peer-evaluation might be considered to augment current SETs.

Organisational learning drives tourism organisations towards more sustainable tourism. Digital transformation also provides opportunities for sustainable tourism development. This study aims to combine these perspectives and explore how digital transformation enables organisational learning to contribute to sustainable tourism, following organisational learning theory (OLT).

Based on a critical realist paradigm, this study focuses on developing an in-depth understanding of organisational learning in tourism organisations. Thirty qualitative interviews with tourism organisations participating in an executive development programme (EDP) show how tourism organisations create, retain and transfer knowledge.

This study demonstrates that the EDP initiates knowledge creation through content transmission and exchange, triggers knowledge retention through utilisation of digital technologies and reinforces digitalisation through data value creation. Furthermore, this study enables knowledge transformation as implementation, which contributes to the three pillars of sustainable tourism and facilitates the development of networks encouraging sustainable tourism.

This study identifies approaches that enable economic, social and environmentally sustainable tourism development by facilitating collaborations via digital transformation, digital technologies that guide guest streams, online mobility offers and online environmental awareness campaigns that reduce environmental impacts. Thus, this study strengthens OLT and has implications for organisational learning and tourism policymakers.

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.

This study aims to investigate the cause of high-order wheel polygonization in a plateau high-speed electric multiple unit (EMU) train.

A series of field tests were conducted to measure the vibration accelerations of the axle box and bogie when the wheels of the EMU train passed through tracks with normal rail roughness after re-profiling. Additionally, the dynamic characteristics of the track, wheelset and bogie were also measured. These measurements provided insights into the mechanisms that lead to wheel polygonization.

The results of the field tests indicate that wheel polygonal wear in the EMU train primarily exhibits 14–16 and 25–27 harmonic orders. The passing frequencies of wheel polygonization were approximately 283–323 Hz and 505–545 Hz, which closely match the dominated frequencies of axle box and bogie vibrations. These findings suggest that the fixed-frequency vibrations originate from the natural modes of the wheelset and bogie, which can be excited by wheel/rail irregularities.

The study provides novel insights into the mechanisms of high-order wheel polygonization in plateau high-speed EMU trains. Futher, the results indicate that operating the EMU train on mixed lines at variable speeds could potentially mitigate high-order polygonal wear, providing practical value for improving the safety, performance and maintenance efficiency of high-speed EMU trains.

Complaint service management, aimed at improving customer satisfaction, provides important content for incorporation into studying a closed-loop supply chain. An analysis of the relationship between two provides the basis for probing the role of complaint management (CM) in the closed-loop supply chain to help it perform more efficiently and effectively through the application of advanced technologies. This paper considers how CM can be computed combining computer communication and information technologies. This computing process involves collection, evaluation and disposal. Using computer telephone integration technology, an integrated multi-channel system is designed; complaint and production evaluated through an intelligent decision support system; and CM processing system established to implement corresponding disposal which reflects the utility of CM. This research on the process of incorporating CM into our studies has significance for computing business service in the future. Based on exergoeconomics theory, the closed-loop supply chain is discussed, and the metric about “system negative environment effect” is introduced to system performance in terms of energy expenditures; a case study illustrates the efficacy of the process