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Topologically interlocked materials are a class of materials in which individual unit elements interact with each other through contact only. Cracks and other defects occurring due to external loading are contained in the individual unit elements. Thus, topologically interlocked materials are damage tolerant and provide high structural integrity. The purpose of this paper is to investigate the concepts of remanufacturing in the context of a material for which the intended use is structural such that the material's structural integrity is of concern. In particular, the study is concerned with the mechanical behavior of a topologically interlocked material.

A topologically interlocked material based on tetrahedron unit elements is investigated experimentally. Manufacturing with aid of a robotically controlled end‐effector is demonstrated, and mechanical properties are determined for a plate configuration. A conceptual mechanical model for failure of topologically interlocked materials is developed and used to interpret the experimental results.

It is demonstrated that remanufacturing of the topologically interlocked material is possible with only a limited loss of material performance. The proposed model predicts trends in agreement with the experimental findings.

While the model predictions are qualitatively in agreement with experiments, more detailed finite element models are needed to predict the material performance accurately. Experiments were conducted on a model material obtained from a 3D printer and should be verified on other solids.

The authors demonstrate that damage containment together with the absence of binders or adhesives enables reuse through remanufacturing without loss of structural integrity.

Topologically interlocked materials emerge as attractive materials for sustainable engineering once their material performance are weighted with an environmental impact factor.

Remanufacturing experiments on a novel class of materials were conducted and a new model for the characterization of the structural integrity of topologically interlocked materials is proposed and successfully evaluated against experiments in at least qualitative form.

Circular economy (CE) is guided by principles, the key being the R-framework. All R-frameworks have a hierarchy. Although several studies have prioritized these principles, there is still an urgent call for country-specific prioritization. This study prioritized circular economy (CE) principles among Ghana's built environment (BE) professionals.

An explanatory sequential mixed methods approach was adopted. Six principles of CE were identified through a review of related literature and incorporated into a questionnaire. In total, 162 questionnaire responses were received. The quantitative data were analyzed through descriptive and inferential analyses. The data were further validated via semi-structured interviews with eight interviewees of different professional backgrounds in the BE.

The findings revealed that BE professionals in Ghana highly perceived CE principles as important. The findings further revealed the order of prioritization of the CE principles as follows: (1) recycle, (2) reuse, (3) repair/remanufacture, (4) renewable energy usage, (5) redesign and (6) reduce. To further elaborate on these prioritized principles via the qualitative phase, the interviewees agreed to and confirmed the importance of the identified principles through their verbatim comments.

Although there is a growing interest in research regarding CE in the Ghanaian construction industry, its principles have yet to be prioritized and ranked by professionals in the Ghanaian construction industry. This study unearths why, in terms of prioritization of the CE principles, the construction industry in Ghana does not follow the well-known hierarchy (i.e. reduce, reuse and recycle) in the order of high to low level of circularity.

This paper designs an optimal closed-loop supply chain network with an integrated forward and reverse logistics to examine the possibility of remanufacturing end-of-life (EoL) ships.

Explanatory variables are used to estimate the number of EoL ships available in a closed-loop supply chain network. The estimated number of EoL ships is used as an input in the model and then it is solved by a mixed-integer linear programming (MILP) model of the closed-loop supply chain network to minimise the total logistic costs. A discounted payback period formula is developed to calculate the length of time to recoup an investment based on the investment's discounted cash flows. Existing ship wrecking industry clusters in the Western region of India are used as the case study to apply the proposed model.

The MILP model has optimised the total logistics costs of the closed-loop supply network and ascertained the optimal number and location of remanufacturing for building EoL ships. The capital and variable costs required for establishing and operating remanufacturing centres are computed. To remanufacture 30 ships a year, the discounted payback period of this project is estimated to be less than two years.

Ship manufacturing businesses are yet to re-manufacture EoL ships, given high upfront capital expenditure and operational challenges. This study provides management insights into the costs and benefits of EoL ship remanufacturing; thus, informing the decision-makers to make strategic operational decisions.

The design of an optimal close loop supply chain network coupled with a Bayesian network approach and discounted payback period formula for the collection and remanufacturing of EoL ships provides a new integrated perspective to ship manufacturing.

This study examines the level of awareness and practice of the principles of circular economy (CE) among built environment (BE) professionals in Ghana.

A structured questionnaire survey was used to solicit the views of 162 BE professionals working in construction, consulting and developer firms on the issue under investigation. Data were analysed through descriptive and inferential analysis.

The findings revealed that the BE professionals possessed moderate awareness of the six CE principles (i.e. repair, recycle, reuse, renewable energy usage, reduce and redesign) examined. The findings further revealed that only two out of the six principles (i.e. repair and reuse) received some moderate level of practice among the professionals.

Practically, the findings would be relevant to government, policymakers, researchers and other construction professionals. For the government and policymakers, these findings would inform them on the laws and policies to enact to increase awareness and practice of CE principles. For researchers, these findings will assist in exploring gaps for further studies. For the construction professionals, the findings would inform them of the need to step up measures to practice the various principles of CE in their firms adequately.

This study provides insights into an under-investigated topic in the construction industry worldwide. It offers new and additional insights into the current state-of-the-art practice of CE principles among BE professionals.

There is now much emphasis in both research and practice on the principles of circular economies. In this paper remanufacturing is examined as a key enabler of circular practices, and the concept of “Product-Agnostic Manufacturing” (PAR) is proposed. This work differentiates PAR from many traditional approaches to remanufacturing by virtue of PAR's treatment of product variety. Most existing approaches to remanufacturing feature low variety and standardisation; this study instead suggests that the exploitation of flexibilities in both operations and supply chains leads to new competitive strategies for firms to exploit.

This is a conceptual study that builds on a thorough exploration of contemporary remanufacturing literature in the development of the new PAR concept.

Through a detailed literature review it is shown that there are a range of benefits, challenges, and critical success factors that underpin the remanufacturing concept. Building on this understanding and bridging literature in operations flexibility and supply chain design, a detailed discussion on the nature of PAR is provided, and an agenda for future research developed.

Whilst there has been much literature on remanufacturing, there is a general tendency to treat supply chain and remanufacturing operations quite distinctly in individual articles. Additionally, there has been little consideration of multi-product remanufacturing, and for the limited studies where this is done, the emphasis is typically on problem avoidance. This study aims to provide a detailed insight into the developed PAR concept, showing how the remanufacture of a wide range of product varieties may be achieved through flexible operations and supply chain design.

The study aims to develop and test a supply chain wide green product development framework of focal firms and their major suppliers, in the context of the Chinese automotive industry.

An in-depth case studies approach is adopted for this study. Three automotive sector upstream supply chains involving 17 firms and 51 experts as respondents were interviewed on the importance and implementation effectiveness of 6Rs (reduce, redesign, recover, remanufacture, reuse and recycle) across the manufacturer and their respective tier 1 and tier 2 suppliers.

The results indicate that the Chinese automotive sector supply chains are mainly focused on “reduce” practices with immediate environmental and economic benefits. The investigated firms however had future implementation plans for “redesign” and “recovery” practices to become comprehensive in green product development (GPD).

The study facilitates automotive firms, industry policymakers and researchers the understanding of incorporating comprehensive GSCM practices across the upstream supply chain to achieve circularity. The study focused on upstream supply chain due to the concentration of major production practices in this section of the supply chain. However, the downstream supply chain equally deserve attention as well as the need to understand the mediating and moderating roles of the different Rs to tease out the pros and cons of achieving overall environmental sustainability.

There are very limited studies on comprehensive GPD for achieving optimal GSCM and sustainability. By simultaneous looking at a focal firm and its upstream supply chains GSCM practices, this study addresses a system-wide comprehensive GPD issues from implementation of 6Rs perspectives in the supply chain.

The purpose of this study is to explore circular economy (CE) initiatives and apply the stimulus-organism-response theory to find the socio-political drivers and enablers of CE in the pharmaceutical industry. CE as a concept was relatively not studied much with respect to socio-political interests from operations management perspectives. This was especially so in the pharmaceutical industry.

This research study was anchored in the theoretical conversation of stimulus-organism-response theory to find the socio-political interests and enablers of the regenerative CE principles. These were the functions of remanufacturing, reuse and recycle. For this research study, data was collected in two steps. First, eight industry practitioners were interviewed to understand the CE practices in the pharmaceutical industry. Then 166 chiefs of production and operations functions from 124 pharmaceutical companies were surveyed. The quantitative data was empirically analyzed using SmartPLS3 software.

This research study revealed that pressure from suppliers and other public stakeholders were driving regenerative CE practices in the pharmaceutical industry. The results further stated that CE enablers such as green information technology systems and internal environmental management were critical for making pharmaceutical manufacturing operations circular.

This research study measured the constructs on a formative scale. Studies measuring socio-political interests, CE enablers and sustainability practices constructs on a formative scale were much required for the development of the CE theory. This research study output could be applied across geographies and industries to measure the indicators of CE.

This research study indicated that in the context of the pharmaceutical industry, there was an overemphasis on the remanufacture and reuse principles. However, the focus on recycling principles was mostly subdued. For managers and regulators in the pharmaceutical sector, this research study provided clear insights that for more effective CE implementation. This was based on an effective application of recycling practices in the critical functions in pharmaceutical industry.

Earlier research studies on green and environmental manufacturing were focused on linear production models. To provide clear and robust foundations for CE theory, this research study considered operations management from the perspective of the value chain. This comprised the entire circular production model. Earlier research studies had treated socio-political interests, CE enablers and sustainability practices as reflective constructs. This study was one of the foremost to measure these constructs on a formative scale.

Proposes that facilities managers can viably utilize building services components that have been designed to be more readily reused to satisfy growing client demands for adaptable buildings. In an increasingly dynamic business environment, many organizations seeking to remain competitive have focused on performing their core function in the short‐term by shedding, among other functions, responsibility for their supporting buildings to external organizations. The growth of the facilities management support industry illustrates this trend. The increasing contribution of services installations to building complexity and value means that the greatest opportunity for facilities managers to improve their efficiency in satisfying constantly changing client space use demands lies in their management of this building element. By utilizing reusable services components, facilities managers may be able to increase the adaptability of both new and existing buildings and reduce the financial impact of change. It is concluded that a new industrial sector may emerge to support services component reuse. This sector will undertake the remanufacture (reconditioning) of such component to ensure their fitness for purpose for reuse.

This paper examines how the level of low-carbon awareness (LCA) affects the remanufacturing strategy in a supply chain with an original equipment manufacturer (OEM) and an independent remanufacturer (IR) competing with each other.

Game theory and operations optimization.

The studies analytically characterize the threshold levels of the LCA in response to which the OEM and the IR will change their remanufacturing strategies from no remanufacturing to partial remanufacturing and then to full remanufacturing. In addition, the studies reveal that as compared with the OEM, the IR has more flexibility in terms of the market entry to remanufacturing with the level of LCA increasing. With the extended studies, it is exhibited that the above findings are robust to a good extent.

It can provide decision support for remanufacturing enterprises.

The purpose of this paper is to investigate the dynamic acquisition pricing strategy for collecting used products (also known as cores or returns) in a finite planning horizon. In particular, this paper studies a cost-minimization model in which a firm offers acquisition price that impacts the quantity of the returns, and remanufactures the used product to satisfy the customer demand.

This paper uses multi-period stochastic dynamic programming theory to model a remanufacturing system that faces the random demand for remanufactured products. The number of the returns at each period is uncertain and increases linearly with the acquisition price offered.

The study shows that when the uncertainty of demand for remanufactured products increases, the remanufacturer should hold a higher core stock level to minimize the expected total cost and thus a higher acquisition price is needed to attract returns. However, given demand uncertainty, the optimal price decreases in the initial core stock level in each period. It also indicates that the optimal acquisition price increases in the variance of the returns, but decreases in the mean of the returns.

The findings suggest that a remanufacturer could reduce the expected total cost by adjusting the acquisition price according to the number of returns periodically.

Introducing the impact of supply uncertainty on the acquisition price of used products, this paper uses a multi-period dynamic model, instead of single period model in previous studies, to examine the remanufacturer’s dynamic acquisition pricing policy.