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Driven by sustainable production, mobile robots are introduced as a new clean-energy material handling tool for mixed-model assembly lines (MMALs), which reduces energy consumption and lineside inventory of workstations (LSI). Nevertheless, the previous part feeding scheduling method was designed for conventional material handling tools without considering the flexible spatial layout of the robotic mobile fulfillment system (RMFS). To fill this gap, this paper focuses on a greening mobile robot part feeding scheduling problem with Just-In-Time (JIT) considerations, where the layout and number of pods can be adjusted.

A novel hybrid-load pod (HL-pod) and mobile robot are proposed to carry out part feeding tasks between material supermarkets and assembly lines. A bi-objective mixed-integer programming model is formulated to minimize both total energy consumption and LSI, aligning with environmental and sustainable JIT goals. Due to the NP-hard nature of the proposed problem, a chaotic differential evolution algorithm for multi-objective optimization based on iterated local search (CDEMIL) algorithm is presented. The effectiveness of the proposed algorithm is verified by dealing with the HL-pod-based greening part feeding scheduling problem in different problem scales and compared to two benchmark algorithms. Managerial insights analyses are conducted to implement the HL-pod strategy.

The CDEMIL algorithm's ability to produce Pareto fronts for different problem scales confirms its effectiveness and feasibility. Computational results show that the proposed algorithm outperforms the other two compared algorithms regarding solution quality and convergence speed. Additionally, the results indicate that the HL-pod performs better than adopting a single type of pod.

This study proposes an innovative solution to the scheduling problem for efficient JIT part feeding using RMFS and HL-pods in automobile MMALs. It considers both the layout and number of pods, ensuring a sustainable and environmental-friendly approach to production.

As an important connecting component, the reliability of aluminium alloy welded joints influences the whole structural effectiveness and stability of equipment. The purpose of this paper is to propose a novel reliability estimation approach to the welded joints based on time-transformed Wiener process with automatic image measurement of crack growth. The crack length information of the welded joints is incorporated into reliability analysis to reflect the product time-varying characteristics.

The proposed approach is superior to other crack growth estimations in that it innovatively introduce a non-contact and flexible photogrammetry technique.First, on-line crack growth images of aluminium alloy welded joints are acquired by the designed monitor system. Second, crack length is calculated with image measurement, then the crack growth data during the manufacturing process is prepared. Finally, a time-transformed Wiener process is used to modeling the degradation, and reliability estimation is carried out with Wiener model. The approach has been validated on five 7075-T7351 welded joint samples.

The method has a twofold task: first, the extraction of crack length growth data by a sequence of image processing. The main step is to model the crack skeleton with crack skeleton tree, and remove it edges to calculate the length of crack; second, the prediction of crack growth and reliability estimation.

The limitation of proposed method should not be ignored. The pixel/mm scale should be calibrated in advance that means once we have built the monitor system, the relative position of the CCD camera and the surveyed crack cannot change anymore. It has reduced the flexibility. To improve this, we can obtain binocular vision in crack image measurement. The 3-D measurements could solve calibration problem and provide more information, such as the depth and the orientation of crack to research. Therefore, future work can be centered on the improvement of monitor system and measurement precision.

In the paper a novel method to estimate reliability of crack growth from welded joint based on image measurement has been presented. This method could be widely applied in different filed of manufacturing systems, reliability engineering and structural analysis.

This paper systematically reviews and scrutinises the current development of studies concerning digital platform use in firms’ internationalisation. It also provides a research agenda for future work. Despite more than two decades of research, the study of how traditional firms enter foreign markets using digital platforms remains in its infancy. This paper contributes insights into the academic and managerial relevance of this field.

A systematic review of the literature based on content analysis was undertaken, drawing from peer-reviewed journal articles in international business, international marketing, information systems, and electronic commerce. The articles were published between 1999 and 2023, and the review employed a vote-counting method.

This analysis of 61 papers indicates that research on digital platform use in firms’ internationalisation is growing rapidly. However, the field itself is fragmented, and the research findings are inconsistent. This dynamic area reflects a growing trend, is dominated by several theories, relies primarily on survey data, and frequently uses China as a research context.

In acknowledging the vibrancy and managerial importance of this field, the authors offer a comprehensive overview of the existing studies to serve as a repository of knowledge on digital platform use in internationalisation for both academics and practitioners. Based on the aforementioned analysis, this study develops a reconciling framework to address current research gaps and identify future study directions.

Regarding the important roles of accuracy and robustness of tightly-coupled micro inertial measurement unit (MIMU)/global navigation satellite system (GNSS) for unmanned aerial vehicle (UAV). This study aims to explore the efficient method to improve the real-time performance of the sensors.

A covariance shaping adaptive Kalman filtering method is developed. For optimal performance of multiple gyros and accelerometers, a distribution coefficient of precision is defined and the data fusion least square method is applied with fault detection and identification using the singular value decomposition. A dual channel parallel filter scheme with a covariance shaping adaptive filter is proposed.

Hardware-in-the-loop numerical simulation was adopted, the results indicate that the gain of the covariance shaping adaptive filter is self-tuning by changing covariance weighting factor, which is calculated by minimizing the cost function of Frobenius norm. With the improved method, the positioning accuracy with tightly-coupled MIMU/GNSS of the adaptive Kalman filter is increased obviously.

The method of covariance shaping adaptive Kalman filtering is efficient to improve the accuracy and robustness of tightly-coupled MIMU/GNSS for UAV in complex and dynamic environments and has great value for engineering applications.

A covariance shaping adaptive Kalman filtering method is presented and a novel dual channel parallel filter scheme with a covariance shaping adaptive filter is proposed, to improve the real-time performance in complex and dynamic environments.

In order to understand the status of the bridge reinforcement process, the construction process monitoring of the reinforced bridge is carried out. The T-beam bridge was tested using the truck loading test. The displacements and concrete strains of the bridge at mid-span were measured during the test.

This paper describes an innovative technique, external prestressing, used to strengthen a 36-year-old prestressed T-beam bridge. This paper introduces the construction process of the prestressed reinforcement method, and makes a theoretical analysis of the reinforced bridge through the establishment of the reinforcement model.

This study showed that the structural capacity and performance of the bridge were enhanced with externally prestressed steel strand strengthening.

The innovative reinforcement method of prestressed T-shaped bridge is put forward, which has guiding significance for similar bridge reinforcement and maintenance.

The paper aims to investigate effectiveness of the strengthening method, the construction process monitoring, fielding-load tests before and after strengthening, and health monitoring after reinforcement were carried out. The results of concrete strain and deflection show that the flexural strength and stiffness of the strengthened beam are improved.

This paper describes prestressed steel strand as a way to strengthen a 25-year-old continuous rigid frame bridge. High strength, low relaxation steel strand with high tensile strain and good corrosion resistance were used in this reinforcement. The construction process for strengthening with prestressed steel strand and steel plate was described. Ultimate bearing capacity of the bridge after strengthening was discussed based on finite element model.

The cumulative upward deflection of the second span the third span was 39.7 mm, which is basically consistent with the theoretical value, and the measured value is smaller than the theoretical value. The deflection value of the second span during data acquisition was −20 mm–10 mm, which does not exceed the maximum deflection value of live load, and the deflection of the bridge is in a safe state during normal use. Thus, this strengthened way with prestressed steel wire rope is feasible and effective.

This paper describes prestressed steel strand as a way to strengthen a 25-year-old continuous rigid frame bridge. To investigate effectiveness of the strengthening method, the construction process monitoring, fielding-load tests before and after strengthening and health monitoring after reinforcement were carried out.

Tour guides often use humor to entertain tourists, but the process of tour guide humor (TGH) affecting tourists’ positive word of mouth (PWOM) remains unclear. To fill the gap, this study aims to investigate how TGH enhances tourists’ PWOM through perceived relationship investment, perceived wellness value and trust in tour guides.

A comprehensive mediation model was proposed based on social exchange theory (SET). Data were obtained from 335 tour group tourists and analyzed using structural equation modeling.

Results present that TGH positively predicts tourists’ PWOM. Perceived relationship investment, perceived wellness value and trust in tour guides not only play mediating roles between TGH and tourists’ PWOM, respectively, but also jointly provide two sequential mediation paths (TGH → perceived relationship investment → trust in tour guides → tourists’ PWOM and TGH → perceived wellness value → trust in tour guides → tourists’ PWOM).

The findings have practical value for tour guides and travel agencies to use TGH to improve tourists’ PWOM.

The major contribution is that a reciprocity-based framework rooted in SET was proposed to parse the complex process of TGH promoting tourists’ PWOM. Furthermore, this study enriches current knowledge by confirming that perceived wellness value is not only available in wellness tourism but can be experienced from TGH in mass tourism.

The application of smart contract can greatly reduce transaction costs and improve transaction efficiency. The existing smart contract are expensive, single application scenario and inefficient. This paper aims to propose a new smart contract model to solve these problems.

By investigating the research history, models and platforms, this paper summarizes the shortcomings of existing smart contracts. Based on the content and architecture of traditional contract, a smart contract model with wider application scope is designed.

In this paper, several models are used to describe the operation mechanism of smart contracts. To facilitate computer execution, a decomposition method is proposed, which divides smart contracts into several sub-contracts. Then, the advantages and deployment methods of smart contract are discussed. On this basis, a specific example is given to illustrate how the application of smart contract will change our life.

Smart contract is gradually applied to more fields. In this paper, the structure and operation mechanism of smart contract system in reality are given, which will be beneficial to the application of smart contract to more complex systems.

Although research on how the downstream calculations of a patent’s profit potential influence invention renewal decisions is extensive, the impact of the upstream knowledge creation stages is overlooked. The purpose of this study is to address this theoretical vacuum by examining the intra-organizational configuration of knowledge networks and collaboration networks.

The data consist of 491 global pharmaceutical firms that patent in the USA. Drawing on patent records, the authors simultaneously construct intra-organizational knowledge networks and collaboration networks and identify network cohesion features (i.e. local and global). The authors employ panel fixed-effects models to test the hypotheses.

The results show that local knowledge cohesion and local social cohesion decrease invention renewals, while global knowledge cohesion and global social cohesion increase renewals. Moreover, the marginal effects of local and global social cohesion are stronger than those of local and global knowledge cohesion, respectively.

The hypotheses are tested using the pharmaceutical industry as a research setting, which limits the generalizability of our findings. In addition, potential formal and informal contingencies are not considered.

Despite its limitations, this study provides valuable implications. First, managers are cautioned against the adverse effects of local cohesion structures on invention renewal. Second, firms can dynamically adjust their local and global network configuration strategies to harmonize the generation of valuable inventions and the retention of good ideas.

Complementary to previous research that focused on inventions’ performance feedback, this study delves into upstream knowledge creation stages to understand invention renewals.

Sustainability is of growing significance in the contemporary business landscape as organizations strive to minimize their environmental impact and optimize supply chain (SC) operations. Gaining insights into the influence of Triple A SC practices on sustainable performance can offer valuable perspectives for practitioners and policymakers. This study aims to comprehensively review existing academic literature on Triple A supply chain management (SCM) and sustainability, examining its impact on sustainable performance while identifying key influencing factors.

This review follows the six steps and 14 decisions of conducting a systematic literature review to comprehensively review 57 papers published between 2004 and 2023.

Based on the content analysis of the selected papers, this study summarizes the antecedents, practices and outcomes of Triple A SCM, with a particular focus on its implications for sustainability. This paper builds a conceptual framework from the descriptive and thematic findings to enrich the relevant aspects of Triple A SCM.

This study establishes a connection between Triple A SCM and sustainable performance by examining its impact on economic, social and environmental aspects. This review identifies research gaps and acknowledges the lack of specificity in implementing Triple A SCM across diverse industries, regions and competitive markets with varying external environments. It emphasizes the necessity to customize approaches based on contextual factors and provides valuable recommendations for future research to advance the concept of Triple A SCM.