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This paper aims to propose a methodology to assist manufacturing companies in the implementation of condition-based maintenance (CBM) to their equipment. The developed methodology intends to consider the use of sensors already installed on the equipment and, when required, to support the selection of sensors available on the market. Since CBM using sensors is not always feasible, the information gathered for the feasibility study of CBM implementation is also used to assign other maintenance strategies.

Based on the literature review, requirements and specifications were established for endowing the methodology with relevant and distinctive characteristics. The structure of the methodology and the associated steps were defined based on this information. Then, the methodology was validated and refined using a case study.

In the case study company, following the methodology and the respective steps, appropriate maintenance strategies were assigned to a selected manufacturing machine, considering information related to the failure modes with the most significant impact, and CBM was applied to a selected component for which the benefit outweighs the costs involved, using data acquired by sensors subsequently installed on the analyzed machine.

Due to its comprehensiveness, this methodology can contribute to make CBM implementation accessible to a high number of companies and encourage the application of a wide variety of monitoring techniques.

This new methodology can be easily integrated into a computerized maintenance management system and has the advantage of facilitating the collection, organization and standardization of technical knowledge required to support CBM implementation and define the most appropriate maintenance strategy systematically and automatically. It guides the prioritization of equipment and failure modes, and the decision-making regarding the selection of sensors and the allocation of maintenance strategies with the aim of reducing costs.

This paper aims to investigate the vertical cooperative relationship between the core enterprise and the manufacturer within the platform ecosystem, specifically analyzing the optimal decision-making processes of both parties under the original equipment manufacturer (OEM) and original brand manufacturer (OBM) modes.

This paper uses game theory to analyze the problem, considering factors such as brand value difference, cross-selling and platform empowerment. It constructs the game models for both OEM and OBM modes and discusses the selection strategies for the cooperation mode.

The results indicate that the choice of cooperation mode by the manufacturer and the core enterprise depends on the relative size of their brand values. In cases of inconsistent choices, cooperation can be improved by designing a transfer payment contract. When the brand value is constant, the product price is comprehensively affected by cross-selling revenue, price elasticity coefficient, cost coefficient of sales effort and cost coefficient of platform empowerment. The enterprise reduces the price only when the potential revenue brought by increasing product sales exceeds the marginal profit brought by increasing product pricing; otherwise, it raises the sales price.

The platform ecosystem is emerging as a future direction for business mode development. However, there is a paucity of research on the cooperation modes between manufacturers and core enterprises within the platform ecosystem.

A transmission tower usually experiences bolt loosening under long-term alternating cyclic load, which may lead to collapse of the tower in extreme operating conditions. The paper aims to propose a data-driven identification method for bolt looseness of complicated tower structures based on reduced-order models and numerical simulations to perceive and evaluate the health state of a tower in operation.

The equivalent stiffnesses of three types of bolt joints under various loosening scenarios are numerically determined by three-dimensional finite element (FE) simulations. The order of the FE model of a tower structure with bolt loosening is reduced by means of the component modal synthesis method, and the dynamic responses of the reducer-order model under calibration loads are simulated and used to create the dataset. An identification model for bolt looseness of the tower structure based on convolutional neural networks driven by the acceleration sensors is constructed.

An identification model for bolt looseness of the tower structure based on convolutional neural networks driven by the acceleration sensors is constructed and the applicability of the model is investigated. It is shown that the proposed method has a high identification accuracy and strong robustness to data noise and data missing. Meanwhile, the method is less dependent on the number and location of sensors and is easier to apply in real transmission lines.

This paper proposes a data-driven identification method for bolt looseness of a complicated tower structure based on reduced-order models and numerical simulations. Non-linear relationships between equivalent stiffness of bolted joints and bolt preload depicting looseness are obtained and reduced-order model of tower structure with bolt looseness is established. Finally, this paper investigates applicability of identification model for bolt looseness.

The purpose of this paper is the dynamic analysis and seismic damage assessment of steel sheet pile quay wall with inelastic behavior underground motions using several accelerograms.

Finite element analysis is conducted using the Plaxis 2D software to generate the numerical model of quay wall. The extension of berth 25 at the port of Bejaia, located in northeastern Algeria, represents a case study. Incremental dynamic analyses are carried out to examine variation of the main response parameters under seismic excitations with increasing Peak ground acceleration (PGA) levels. Two global damage indices based on the safety factor and bending moment are introduced to assess the relationship between PGA and the damage levels.

The results obtained indicate that the sheet pile quay wall can safely withstand seismic loads up to PGAs of 0.35 g and that above 0.45 g, care should be taken with the risk of reaching the ultimate moment capacity of the steel sheet pile. However, for PGAs greater than 0.5 g, it was clearly demonstrated that the excessive deformations with material are likely to occur in the soil layers and in the structural elements.

The main contribution of the present work is a new double seismic damage index for a steel sheet pile supported quay wharf. The numerical modeling is first validated in the static case. Then, the results obtained by performing several incremental dynamic analyses are exploited to evaluate the degradation of the soil safety factor and the seismic capacity of the pile sheet wall. Computed values of the proposed damage indices of the considered quay wharf are a practical helping tool for decision-making regarding the seismic safety of the structure.

To prevent the coil from burning or getting damaged, it is necessary to estimate the duration of its operation as long as its temperature does not exceed the permissible limit. This paper aims to investigate the effect of switching on the thermal behavior of impregnated and nonimpregnated windings. Also, the safe operating time for each winding is determined.

The power loss of the winding is expressed as a function of the winding specifications. Using homogenization techniques, the equivalent thermal properties for the homogenized winding are calculated and used in a proposed thermal equivalent circuit for winding modeling and analysis. The validity and accuracy of the proposed model are determined by comparing its analysis results and simulation and measurement results.

The results show that copper windings have better thermal behavior and lower temperature compared to aluminum windings. On the other hand, by impregnating or increasing the packing factor of the winding, the thermal behavior is improved. Also, by choosing the right duty cycle for the winding current source, it is possible to prevent the burning or damage of the winding and increase its lifespan. Comparing the measurement results with the analysis results shows that the proposed equivalent circuit has an error of less than 4% in the calculation of the winding center temperature.

In this paper, the effect of temperature on the electrical resistance of the coil is ignored. Also, rectangular wires were not investigated. Research in these topics are considered as future work.

By calculating the thermal time constant of the winding, its safe operation time can be calculated so that its temperature does not exceed the tolerable value (150 °C). The proposed method analyzes both impregnated and nonimpregnated windings with various schemes. It investigates the effects of switching on their thermal behavior. Additionally, it determines the safe operating time for each type of winding.

Packaging-free shopping disrupts the usual retailing and consumption patterns in which packaging usually plays a central role. When manufacturers no longer offer predetermined packaging, how do retailers and consumers ensure packaging functions? Investigating the way packaging-free actors appropriate packaging functions during use is particularly important because they exert a new power over these functions, which can be challenging to appropriate. The purpose of this study is to contribute to a deeper understanding of why packaging-free shopping can be perceived as constraining.

Drawing from the literature on packaging functions and adopting Miller’s conceptual framework of appropriation, this research uses a qualitative method with a variety of discursive and visual data, including 54 interviews with experts from packaging-free product stores and consumers, 190 Instagram consumer posts and 428 in-store and at-home photographs.

This research shows that packaging-free actors jointly appropriate packaging functions through two modes of appropriation (assimilation and accommodation) each encompassing distinct strategies and highlights the misappropriation that actors can experience, especially when prioritizing one function over another.

This research contributes to the literature on packaging-free shopping, an emergent and growing trend that challenges conventional shopping models. The research reveals dark sides of packaging-free shopping – namely, the damaging effects on health and the environment and social exclusion. In particular, it discusses the ambivalence of the packaging-free shopping environmental function. This research also deepens insight into how individual acts of appropriation may lead to misappropriation.

This study presents a systematic literature review (SLR) of the interdisciplinary literature on drones in last-mile delivery (LMD) to extrapolate pertinent insights from and into the logistics management field.

Rooting their analytical categories in the LMD literature, the authors performed a deductive, theory refinement SLR on 307 interdisciplinary journal articles published during 2015–2022 to integrate this emergent phenomenon into the field.

The authors derived the potentials, challenges and solutions of drone deliveries in relation to 12 LMD criteria dispersed across four stakeholder groups: senders, receivers, regulators and societies. Relationships between these criteria were also identified.

This review contributes to logistics management by offering a current, nuanced and multifaceted discussion of drones' potential to improve the LMD process together with the challenges and solutions involved.

The authors provide logistics managers with a holistic roadmap to help them make informed decisions about adopting drones in their delivery systems. Regulators and society members also gain insights into the prospects, requirements and repercussions of drone deliveries.

This is one of the first SLRs on drone applications in LMD from a logistics management perspective.

The use of recycled coarse aggregate in concrete structures promotes environmental sustainability; however, performance of these structures might be negatively impacted when it is used as a replacement to traditional aggregate. This paper aims to simulate recycled concrete beams strengthened with carbon fiber-reinforced polymer (CFRP), to advance the modeling and use of recycled concrete structures.

To investigate the performance of beams with recycled coarse aggregate concrete (RCAC), finite element models (FEMs) were developed to simulate 12 preloaded RCAC beams, strengthened with two CFRP strengthening schemes. Details of the modeling are provided including the material models, boundary conditions, applied loads, analysis solver, mesh analysis and computational efficiency.

Using FEM, a parametric study was carried out to assess the influence of CFRP thickness on the strengthening efficiency. The FEM provided results in good agreement with those from the experiments with differences and standard deviation not exceeding 11.1% and 3.1%, respectively. It was found that increasing the CFRP laminate thickness improved the load-carrying capacity of the strengthened beams.

The developed models simulate the preloading and loading up to failure with/without CFRP strengthening for the investigated beams. Moreover, the models were validated against the experimental results of 12 beams in terms of crack pattern as well as load, deflection and strain.

This study was aimed at clarifying the post-fire shear strength of self-drilling screws and the load-bearing capacity of single overlapped screwed connections using steel sheets and self-drilling screws. The self-drilling screws for shear tests were made of high-strength, martensitic-stainless and austenitic stainless-steel bars.

Shear loading tests were conducted on self-drilling screws to obtain basic information on post-fire shear strength. Tensile tests were conducted on the screwed connections to examine the transition of failure modes depending on the test temperature after experiencing the heating and cooling procedures.

The post-fire shear strengths and reduction factors of self-drilling screws of each steel grade were quantified. Furthermore, heated temperature-dependent sheet bearing failure, net sheet failure and screw shear failure modes were observed for the screwed connections.

The transition of the failure modes of the screwed connection could be explained using the equations of the post-fire shear strength proposed in this study. The basic experimental data required to evaluate the post-fire shear strength of screws were obtained.

We focus on multi-level heterogeneity in board interlocks by accounting for the experience of the “tied-to” firm and the efficacy of the channel for knowledge transfer. Specifically, we study the role of board interlocks of a focal firm with cross-border acquirers and their implications on the entry mode decision (greenfield vs acquisitions). While studying board interlocks, we also consider the type of directors (inside vs independent) that form the interlocks. We situate our research within the context of knowledge-intensive industries in emerging markets. By focusing on heterogeneity in board interlocks, we consider the interplay between experiential and vicarious learning and its implication on a firm’s foreign market entry mode choice.

We conduct our analysis on a propriety dataset of 450 foreign market entries by Indian firms belonging to knowledge-intensive industries during the period 2003 to 2013. We use a binomial logistic regression model to analyze the choice between greenfield ventures and cross-border acquisitions.

We find that firms are more likely to choose cross-border acquisitions over greenfield ventures when connected to other cross-border acquirers through inside and independent director interlocks. However, this effect is more substantial for inside director interlocks. Foreign institutional investors’ shareholding weakens the impact of inside director interlocks but strengthens the effect of independent director interlocks. A firm’s cross-border acquisition experience weakens the impact of independent director interlocks. Still, it enhances the effect of inside director interlocks on the likelihood of choosing cross-border acquisitions over greenfield ventures.

The study highlights heterogeneity in board interlocks and the effectiveness of channels of transfer of learning. It also highlights boundary conditions of board interlocks’ effectiveness in shaping the entry mode decision by elucidating the biases within different actors in the organizational learning process.