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Snap fits are crucial in automotive applications for rapid assembly and disassembly of mating components, eliminating the need for fasteners. This study aims to focus on designing and analyzing serviceable cantilever fit snap connections used in automobile plastic components. Snap fits are classified into permanent and semi-permanent fittings, with permanent fittings having a snap clipping angle between 0° and 5° and semi-permanent fittings having a clipping angle between 15° and 45°. Polypropylene random copolymer is chosen for its exceptional fatigue resistance and elasticity.

The design process includes determining dimensions, computing assembly, disassembly pressures and creating three-dimensional computer-aided design models. Finite element analysis (FEA) is used to evaluate the snap-fit mechanism’s stress, deformation and general functionality in operational scenarios.

The study develops a modified snap-fit mechanism with decreased bending stress and enhanced mating force optimization. The maximum bending stress during assembly is 16.80 MPa, requiring a mating force of 7.58 N, while during disassembly, it is 37.3 MPa, requiring a mating force of 16.85 N. The optimized parameters significantly improve the performance and dependability of the snap-fit mechanism. The results emphasize the need of taking into account both the assembly and disassembly processes in snap-fit design, because the research demonstrates greater forces during disassembly. The approach developed integrates FEA and design for assembly (DFA) concepts to provide a solution for improving the efficiency and reliability of snap-fit connectors in automotive applications.

The research paper’s distinctiveness comes from the fact that it presents a thorough and realistic viewpoint on snap-fit design, emphasizes material selection, incorporates DFA principles and emphasizes the specific requirements of both assembly and disassembly operations. These discoveries may enhance the efficiency, reliability and sustainability of snap-fit connections in plastic automobile parts and beyond. In conclusion, the idea that disassembly needs to be done with a lot more force than installation in a snap-fit design can have a good effect on buzz, squeak and rattle and noise, vibration and harshness characteristics in automobiles.

Although disassembly balancing lines has been studied for over two decades, there is a gap in the robotic disassembly. Moreover, combination of problem with heterogeneous employee assignment is also lacking. The hazard related with the tasks performed on disassembly lines on workers can be reduced by the use of robots or collaborative robots (cobots) instead of workers. This situation causes an increase in costs. The purpose of the study is to propose a novel version of the problem and to solve this bi-objective (minimizing cost and minimizing hazard simultaneously) problem.

The epsilon constraint method was used to solve the bi-objective model. Entropy-based Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) and Preference Ranking Organization methods for Enrichment Evaluation (PROMETHEE) methods were used to support the decision-maker. In addition, a new criterion called automation rate was proposed. The effects of factors were investigated with full factor experiment design.

The effects of all factors were found statistically significant on the solution time. The combined effect of the number of tasks and number of workers was also found to be statistically significant.

In this study, for the first time in the literature, a disassembly line balancing and employee assignment model was proposed in the presence of heterogeneous workers, robots and cobots to simultaneously minimize the hazard to the worker and cost.

In recent times, reverse logistics (RL) is gaining significant traction in various automobile industries to recapture returned vehicles’ value. A good RL program can lower manufacturing costs, establish a green supply chain, enhance customer satisfaction and provide a competitive advantage. However, reducing disruptions and increasing operational efficiency in the automobile RL requires implementing innovative technology to improve information flow and security. Thus, this manuscript aims to examine the hurdles in automobile RL activities and how they can be effectively tackled by blockchain technology (BCT). Merging BCT and RL provides the entire automobile industry a chance to generate value for its consumers through effective vehicle return policies, manufacturing cost reduction, maintenance records tracking, administration of vehicle information and a clear payment record of insurance contracts.

This research is presented in three stages to accomplish the task. First, previous literature and experts' opinions are examined to highlight certain factors that are an aggravation to BCT implementation. Next, this study proposed an interval-valued intuitionistic fuzzy set (IVIFS) – decision-making trial and evaluation laboratory (DEMATEL) with Choquet integral framework for computing and analyzing the comparative results of factor interrelationships. Finally, the causal outline diagrams are plotted to determine the influence of factors on one another for BCT implementation in automobile RL.

This study has categorized the barriers to BCT implementation into five major factors – operational and strategical, technical, knowledge and behavioral, financial and infrastructural, and government rules and regulations. The results revealed that disreputable technology, low-bearing capacity of IT systems and operational inefficiency are the most significant factors to be dealt with by automobile industry professionals for finer and enhanced RL processes utilizing BCT. The most noticeable advantage of BCT is its enormous amount of data, permitting automobile RL to develop client experience through real-time data insights.

This study reveals several factors that are hindering the implementation of BCT in RL activities of the automobile industry. The results can assist experts and policymakers improve their existing decision-making systems while making an effort to implement BCT into the automobile industry's RL activities.

Although there are several studies on the benefits of BCT in RL and the adoption of BCT in the automobile industry, individually, none have explicated the use of BCT in automobile RL. This is also the first kind of study that has used IVIFS-DEMATEL with the Choquet integral framework for computing and analyzing the comparative results of factor interrelationships hindering BCT implementation in automobile RL activities.

There is a renowned interest in adaptability as an important principle for achieving circularity in the built environment. Circular building adaptability (CBA) could enable long-term building utilisation and flexible use of space with limited material flows. This paper identifies and analyses design strategies facilitating CBA to propose a framework for enhancing the implementation of the concept.

Interviews were conducted with professionals experienced in circular building design to explore the questions “How do currently applied design strategies enable CBA?” and “How can CBA be implemented through a conceptual design framework?”. The interviews encircled multi-residential building examples to identify currently applied circular design strategies. The interviews were analysed through qualitative content analysis using CBA determinants as a coding framework.

The results show that all ten CBA determinants are supported by design strategies applied in current circular building design. However, some determinants are more supported than others, and design strategies are often employed without explicitly considering adaptability. The design strategies that enable adaptability offer long-term solutions requiring large-scale modifications rather than facilitating low-impact adaptation by dwelling occupants. The proposed conceptual design framework could aid architects in resolving these issues and implementing CBA in their circular building design.

This paper’s contribution to CBA is threefold. It demonstrates design strategies facilitating CBA, proposes a conceptual design framework to apply the concept and identifies the need for a more comprehensive application of available adaptability strategies.

Inventory is a crucial part of a systematic supply chain of a business. Small firms mostly neglect inventory management (IM) by accumulating excessive inventory for a time. The study aims to examine the IM practices of small and medium enterprises (SMEs) in Bangladesh.

The study applied a qualitative case study design. Data were collected from ten SME owners in Bangladesh. The study employed a purposive sampling technique to collect data. This study used semi-structured interviews to generate data. The NVivo software was used to analyze the data.

The findings show that most SME business owners collect raw materials from the local market. Along with the local sources, they collect raw materials from international markets. Some SME entrepreneurs collect raw materials throughout the country as they dealt with recycled products. Frequently, they used digital technologies and online media to manage raw materials. SME owners could not buy many raw materials due to financial crisis, wastage, and damage, leading to a ratio of 10–15% losses.

This research contributes greatly to the government, SME Foundation, and trade associations concerning the SME IM system. The study recommends the government should reduce the tax rate on importing SME raw materials and inventories and exporting SME products.

This is the first study that focuses on the IM systems of SMEs in Bangladesh.

The purpose of this paper is to investigate and quantify the impact of product complexity, including architectural complexity, on operator learning, productivity and quality performance in both assembly and disassembly operations. This topic has not been extensively investigated in previous research.

An extensive experimental campaign involving 84 operators was conducted to repeatedly assemble and disassemble six different products of varying complexity to construct productivity and quality learning curves. Data from the experiment were analysed using statistical methods.

The human learning factor of productivity increases superlinearly with the increasing architectural complexity of products, i.e. from centralised to distributed architectures, both in assembly and disassembly, regardless of the level of overall product complexity. On the other hand, the human learning factor of quality performance decreases superlinearly as the architectural complexity of products increases. The intrinsic characteristics of product architecture are the reasons for this difference in learning factor.

The results of the study suggest that considering product complexity, particularly architectural complexity, in the design and planning of manufacturing processes can optimise operator learning, productivity and quality performance, and inform decisions about improving manufacturing operations.

While previous research has focussed on the effects of complexity on process time and defect generation, this study is amongst the first to investigate and quantify the effects of product complexity, including architectural complexity, on operator learning using an extensive experimental campaign.

The reuse of timber building parts, when designing new buildings, has become a topic of increasing discussion as a proposed circular solution in support of sustainable development goals. Designers face the difficulty of identifying and applying different design strategies for reuse due to multiple definitions, which are used interchangeably. The purpose of this study is to propose a taxonomy to define the relationships between various concepts and practices that comprise the relevant strategies for reuse, notably design for disassembly (DfD) and design for adaptability (DfA).

Literature reviews were conducted based on research publications over the previous 12 years and located through the Web of Science and Scopus.

A taxonomy for the design process grounded on two strategies for reuse is presented: DfD and DfA. Based on previous work, the taxonomy aims to build a vocabulary of definitions in DfD and DfA to support other researchers and practitioners working in the field.

The research is limited to the design phase of timber-based buildings. It does not take into account the other phases of the construction process, neither other kind of construction methods.

The application of the taxonomy can facilitate communication between different actors and provide a way for building product manufacturers to demonstrate their reuse credentials, enabling them to produce and promote compliant products and thereby support design for reuse strategies.

This paper could contribute to a closer collaboration of all stakeholders involved in the building process since the very early phases of the conceptual design.

This paper contributes a comprehensive taxonomy to support the deployment of circular reuse strategies and assist designers and other stakeholders from the earliest of phases in the building’s life cycle. The proposed definition framework provided by the taxonomy resolves the longstanding lack of a supporting vocabulary for reuse and can be used as a reference for researchers and practitioners working with the DfD and DfA.

This study proposes a garment modularization model based on an interactive genetic algorithm. The suggested model consists of extraction and identification of parts and the determination and implementation of connections. Rules and corresponding mathematical equations have been formulated for the part's extractions from the discarded products and connections for the redesigned products.

Sustainability entices scholars and practitioners while referring to reducing waste to control environmental degradation. One of the ways to safeguard natural resources is to increase the reuse of old or discarded products. The current study focuses on the redesign process to improve the reuse of products.

The intelligent system proposed based on the modularization techniques is expected to simplify and quantify the redesign process. The model can further help in the minimization of wastage and environmental degradation.

Presently, manual decisions are taken by the designers based on their memory, experience and intuition to extract and join the parts.

This study aims to identify in literature the role of construction stakeholders in the implementation of circular economy (CE) in the construction industry (CI). This study also sought to identify the status quo and research trend, “hot themes”, areas requiring more research and future research direction of stakeholders’ role in CE implementation in the CI.

A literature search was conducted using the Scopus search engine, augmented by Google Scholar to produce 50 relevant articles for the identification of stakeholders’ roles using content analysis. The scientometric study was undertaken using VOSviewer on 42 articles obtained from Scopus search to identify the status quo, “hot themes”, knowledge gaps and future research direction of the role of stakeholders in CE implementation.

Through content analysis, the identified roles of government as a stakeholder are to develop efficient policy instruments, legislation support and financial investment in research and development activities that will promote the smooth implementation of CE. The role of academia/research is to engage in research aimed at investigating both the short-term behaviour and the durability of recycled materials and products. In addition, the roles of professionals in the consultant/design/procurement team are to design with life cycle assessment and reused materials, design for deconstruction and disassembly, etc. The role of the user/consumer is to ensure knowledge diffusion and awareness exchange that recognize the available opportunities for long-term material usage (including repair, reuse, refurbishment and recycling). The research status quo identified from the scientometric analysis include how stakeholders can come up with innovative ways in demolition that will ensure that more of the materials can be reused. Stakeholders should focus on enacting policies and laws that can promote the use of recycled materials in buildings, etc. Research that focuses on how to engage the various construction stakeholders to come up with specific public policy that will promote CE implementation, identifying the specific roles to be played by stakeholders during policy enactment as well as managing the environment, laws and legislations towards CE implementation. The role of stakeholders in the extension of the life span of projects, the use of strategies to minimize waste generation and standardization of building materials, components and connectors with the purpose of simplifying disassembly are the research gaps and areas for future research studies. Some of the research “hot themes” include “circular business models in the CI”, “environmental sustainability policy implementation”, “environmental, economic and social sustainability”, “policy, laws and legislations on waste management” and “environmental and industrial economics” towards CE implementation.

The findings from this study serve as a valuable reference for construction stakeholders to assess their specific roles as stakeholders and to identify the status quo and research trend, “hot themes”, areas requiring more research and future research directions on stakeholders’ roles in CE implementation in the CI.

Identifying the role of stakeholders for CE implementation is one bold step towards the achievement of CE implementation in the CI.

This paper aims to explore UAE's transition towards circular economy (CE) through construction and demolition waste (CDW) management in the pre-construction stage. The extent of circularity is assessed by five key aspects of CE, such as policies and strategic frameworks, design for waste prevention, design for disassembly or deconstruction, use of prefabricated elements and CDW management plans.

Multiple case studies were conducted in the context of the Dubai construction industry (UAE). Three significant and unique construction projects were selected as the cases. Semi-structured interviews were carried out to collect data, and the thematic analysis technique and NVIVO 12 software were used for data analysis.

Findings reveal several positive initiatives towards CE in the UAE context; yet it is identified that the transition is still at the initial stage. Selected case studies, the best-case scenarios of UAE (i.e. influential cases), demonstrated adequate measures in relation to four key CE aspects out of five. For instance, (a) policies and strategic frameworks such as lean standards, green building standards and standards developed by the local authorities, (b) design for waste prevention (e.g. adherence to the 3R principle, and construction planning with BIM), (c) use of prefabricated elements and application of innovative construction technologies (e.g. 3DPC, DfMA) and (d) CDW management planning such as 3R principle were evident. However, the selected cases hardly showcase designing for disassembly or deconstruction.

The existing CDW practices are mostly conventional, as most constructions in UAE are procured through conventional building materials and methods. Therefore, there is a necessity of encouraging CE principles in CDW management. Even though the transition towards CE was evident in four key CE aspects out of five, the UAE construction industry has yet to adopt more effective CE-based CDW management practices to accelerate the circularity. Hence, it is necessary to enforce standard waste management guidelines, including the 3R principle, to standardise CDW management in UAE and encourage construction practitioners to adhere to CE principles.

The findings of this study provide valuable insights for decision-making processes around CDW management towards a CE. This paper contributes to the literature by bridging the CE concept with CDW management in the pre-construction stage. The study provides insights for industry practitioners for planning CE in terms of policies and strategic frameworks, CDW management planning, construction planning and application of innovative construction technologies.