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To obtain more reliable crash simulations the history of the structure related to the forming process is considered. For this goal the variables defining the current state have to be transferred from one mesh to the other in order to maintain a consistent discretization of the whole structure consisting of several pre‐formed parts. This is accomplished here by remeshing the structure after the forming process and by transferring the current mechanical properties. In performing such a transfer a numerical error cannot be avoided; the results of this approach are therefore compared with computations in which this transfer is not applied to assess the performance of the presented procedure.

The purpose of this paper is to present a quadrilateral shell element using 16 degrees of freedom (dof) (12 translations and four rotations) which makes a pair with Morley's triangle at 12 dof. This latter has been updated by Batoz who later proposed an extension to a quadrilateral (“DKQ16”) but only with special interpolation functions for an elastic behaviour of the material. Precisely, it is in order to release from this strong limitation that a completely different formulation is proposed here.

The development of this new quadrilateral called “DKS16” involves three stages. The first one starts from Morley's triangle updated by Batoz (“DKT12”) to derive a rotation‐free (RF) triangular element (“S3”). The second stage consists in generalising this triangle to a RF quadrilateral (“S4”). During the final leg, the S4 and DKT12 main features are combined to give the quadrilateral “DKS16”.

Other parameters being equal, the type of finite element chosen for the forming stage simulation has a great influence on further springback result even in software with automatic remeshing. Particularly, it is pointed out that the RF shell elements S3 and S4 as well as the triangle DKT12 are less sensitive to the mesh size than classical shell elements with six dof per node. But, even if some improvements of in‐plane shear have been proposed, stamping codes users are reluctant to use triangles. That is why this paper presents an attempt to extrapolate a quadrilateral (DKS16) from the triangle DKT12 via S3 and S4 elements formulation. Numerous examples showing convergence and accuracy are presented: irregular meshes, large displacement analyses and deep‐drawing simulations.

The triangular “S3” element is already implemented in RADIOSS^® software and its implementation – as well as the one of “DKT12” – is in progress in Pam‐Stamp, both as “user elements”. The next step will be the implementation of the quadrilateral “S4” (RF) and, maybe, the element “DKS16” since both are cheaper in terms of computation time and are found interesting for sheet forming.

It seems obvious that curvatures are more exactly captured in RF elements (when nodes slide on die radius) since they are imposed in terms of translations instead of traditional nodal rotations not managed by contact conditions. As the neighbours are involved, a drawback of these RF elements is their complex formulation in case of branching surfaces and/or abrupt variations in material behaviour and/or thickness. This is not the case for elements such as DKT12 or DKS16, good candidates to add to the (long) list of cheap shell elements for large scale computations typical of sheet metal forming.

The aim of this paper is to present an enriched formulation of a rotation‐free (RF) triangular shell element in order to use it for shells of general shapes while, up to now, it is limited to shells without branching surfaces and progressive variations in terms of material behavior and thickness.

The formulation keeps the main characteristic of Morley's element: bending effects can be expressed with three “bending angles” only. But, for a RF element, these angles are defined with the rigid body rotations of the element itself and those of its neighbours. This usual formulation of a RF shell element can be extended provided that curvatures‐displacements relation involves the material characteristics of the element itself and of its neighbours and the same goes for thickness.

Numerous examples with regular and irregular meshes of structures involving branching surfaces point out convergence and accuracy. Large displacement analyses – including crash simulations – show the effectiveness, too. A deep‐drawing of a “U” shape and the following springback prediction highlight the fact that the curvatures are captured more exactly (when nodes slide on die radius) since they are imposed in terms of translations whereas they are traditionally computed with nodal rotations not managed by contact conditions on the tooling.

The “S3” element detailed here is implemented in RADIOSS^® software. The general conclusions are that this triangle often gives almost the same result as “DKT18” but is two times less cheaper and it is found interesting for sheet forming simulations.

Specificity of such an element clearly appears while lifting the initial restrictions quoted before.

FEM analysis has been increasingly employed to simulate sheetmetal forming processes for industrial application purposes. From the simulation results, finite element analysts are able to predict the occurrences of splits and wrinkles therefore they can make recommendations of changes to the die design and/or to the part design to avoid possible stamping failures. The number of real die tryouts can be reduced, thus, the design cycle is shortened and manufacturing costs lowered. In the early times, application analysts were mostly concentrated on simulation of the stamping process itself starting from simple models, later running full size 3D models with large number of elements.

The purpose of this paper is to compare the performance of implicit and explicit integration schemes for simulating the metal rolling process using commercial software packages ANSYS™ and LS-DYNA™.

For the industrial application of finite element method, the time discretization is one of the most important factors that determine the stability and efficiency of the analysis. An iterative approach, which is unconditionally stable in linear analyses, is the obvious choice for a quasi-static problem such as metal rolling. However, this approach may be challenging in achieving convergence with non-linear material behavior and complicated contact conditions. Therefore, a non-iterative method is usually adopted, in order to achieve computational accuracy through very small time steps. Models using both methods were constructed and compared for computational efficiency.

The results indicate that the explicit method yields higher levels of efficiency compared to the implicit method as model complexity increases. Furthermore, the implicit method displayed instabilities and numerical difficulties in certain load conditions further disfavoring the solver’s performance.

Comparison of the implicit and explicit procedures for time stepping was applied in 3D finite element analysis of the plate rolling process in order to evaluate and quantify the computational efficiency.

The purpose of this paper is to empirically investigate the role of the placement (i.e. location) of humanoid service robots (HSRs) for entertainment applications in retailing by inspecting a multitude of performance metrics along the point-of-sale conversion funnel.

The study was conducted using unobtrusive observations at a Belgian chocolate store. In total, 42 h of video observation material was collected and analyzed, with an even spread over three conditions: (1) an HSR placed outside, (2) an HSR inside the store and (3) a control condition (no robot stimuli). All passersby and their interactions with the robot and the store were systematically coded and compared.

The study found that the better placement of HSRs (inside or outside the store) is contingent on the goals the retailer prioritizes. When the goal is to create awareness and interest toward the store, the HSR should be placed outside, as it has double the stopping power. To induce consumers to enter the store, placement of the HSR inside the store is the better option. Ultimately, however, in terms of the number of transactions and total amount spent, outside placement of the HSR outperforms inside placement.

This study was not able to verify the internal emotional/cognitive state of the passersby, as the method relied on unobtrusive camera observations. A longitudinal research design would be desirable to exclude potential bias due to the novelty effect.

While research on robots in retail services is emerging, this study is the first to provide insights on how retailers can decide on the placement of robots inside or outside the store, depending on the particular goals they are aiming to reach at the point of purchase.

This paper aims to explore and review the potential of robotic rehabilitation as a treatment approach for Alzheimer’s disease (AD) and its impact on the health and quality of life of AD patients.

The present discourse endeavors to provide a comprehensive overview of extant scholarly inquiries that have examined the salience of inhibitory mechanisms vis-à-vis robotic interventions and their impact on patients with AD. Specifically, this review aims to explicate the contemporary state of affairs in this realm by furnishing a detailed explication of ongoing research endeavors. With the objective of elucidating the significance of inhibitory processes in robotic therapies for individuals with AD, this analysis offers a critical appraisal of extant literature that probes the intersection of cognitive mechanisms and assistive technologies. Through a meticulous analysis of diverse scholarly contributions, this review advances a nuanced understanding of the intricate interplay between inhibitory processes and robotic interventions in the context of AD.

According to the review papers, it appears that implementing robot-assisted rehabilitation can serve as a pragmatic and effective solution for enhancing the well-being and overall quality of life of patients and families engaged with AD. Besides, this new feature in the robotic area is anticipated to have a critical role in the success of this innovative approach.

Due to the nascent nature of this cutting-edge technology and the constrained configuration of the mechanized entity in question, further protracted analysis is imperative to ascertain the advantages and drawbacks of robotic rehabilitation vis-à-vis individuals afflicted with Alzheimer’s ailment.

The potential for robots to serve as indispensable assets in the provision of care for individuals afflicted with AD is significant; however, their efficacy and appropriateness for utilization by caregivers of AD patients must be subjected to further rigorous scrutiny.

This paper reviews the current robotic method and compares the current state of the art for the AD patient.

The circular economy (CE) represents an industry-wide transition from linear to circular processes. There has been a proliferation of literature on CE in the last decade. However, the existing studies on the adaption of CE in small and medium-sized enterprises (SMEs) are scarce. This study aims to develop a research agenda and the way forward for future researchers focusing on the adoption of CE.

This article analyses the CE concepts through a Systematic Literature Review (SLR). Coding and content analysis are performed to generate emergent themes with the help of “Atlas.ti” software.

The authors uncovered the contemporary significance of adopting CE and the state-of-the-art literature on CE. The study's findings fall into four broad themes: Technical know-how, resource and process optimization, reverse practices and technology and innovation. Ten thought-provoking questions were identified in the four themes that researchers can explore further in embracing CE to achieve sustainability in SMEs.

The study has highlighted the importance of CE adoption and CE's benefits to stakeholders across all three dimensions, i.e. social, economic and ecological. Practitioners can use the agenda in four themes to strengthen the practitioners' existing practices in SMEs to promote CE.

The study's uniqueness is the supply of current knowledge from diverse literature and practical consequences for SMEs. This study opens new lines of inquiry to adopt CE in SMEs, streamlining the existing literature into four themes to focus future research.

The purpose of this paper is to explore the use of chiral single‐walled carbon nanotubes (SWCNTs) as mass sensors. Analysis of SWCNT with chiralities is performed using an atomistic finite element model based on a molecular structural mechanics approach.

The cantilever carbon nanotube (CNT) is modeled by considering it as a space frame structure similar to three‐dimensional beams and point masses. The elastic properties of the beam element are calculated by considering mechanical characteristics of covalent bonds between the carbon atoms in the hexagonal lattice. The mass of each beam element is assumed as point mass at nodes coinciding with carbon atoms. An atomistic simulation approach is used to find the natural frequencies and to study the effects of defect like atomic vacancies in CNTs on the resonant frequency. The migration of the atomic vacancies along the length is observed for different chiralities.

A reduction in the simulated natural frequency is observed with the maximum value occurring, when the vacancy is found nearer to the fixed end. It is quite evident from the simulation results that the effect of vacancies is significant, and the effect diminishes at 10⁻² femtograms mass. Using the higher modes of vibration of SWCNT‐based mass sensors, the amount and the position of the mass on the nanotube can be identified.

CNT have been used as mass sensors extensively. The present approach is focused to explore the use of chiral SWCNT as sensing device with vacancy defect in it. The variation of the atomic vacancies in CNT along the length has been taken and is analyzed for different chiralities. The effects of defect like atomic vacancies in CNTs on the resonant frequency have been analyzed and observed that the maximum reduction in natural frequency occurs when the vacancy is found nearer to the fixed end due to large stiffness variation.

This study aims to explore how a postmodern tribe enacts and re-interprets ideologies as a part of consumers’ collective experience, to enhance our understanding of consumer communities in conjunction with ideological capacities.

The community of “presenteers” is conceptualized as a self-organized tribe with heterogeneous components that generate capacities to act. Netnographic observation was conducted on 18 presenteer accounts and lasted around six months. Real-time data were collected by taking screenshots of the posts and stories that these users created and publicly shared. Data were analysed by adopting assemblage theory, combining inductive and deductive approaches. Firstly, a qualitative visual-textual content analysis of the tribe’s defining components was conducted. Then, the process continued with the thematic analysis of the ideological underpinnings of the tribe’s enactments.

Findings shed light on the ways in which consumer communities interpret the entanglement of religious, political, and cultural ideologies in shaping their experiences. In the case of the presenteers tribe, findings reflect a novel ideological interplay between neo-Ottomanism, post-feminism and consumerism.

The study offers a deep dive into a unique tribe that is being organized around the consumer-created practice of “presenteering” and investigates consumer communalization in alignment with the ideological turn in culture-oriented interpretative research on consumers, consumption, and markets. This exploration helps to bridge the research on the communalization of consumers with the recent discussions of ideology in the postmodern market.

The study offers a deep dive into a unique tribe that is being organized around the consumer-created practice of “presenteering” and investigates consumer communalization in alignment with the ideological turn in culture-oriented interpretative research on consumers, consumption, and markets. This exploration helps to bridge the research on the communalization of consumers with the recent discussions of ideology in the postmodern market.