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1 – 10 of 85José I.V. Sena, Cedric Lequesne, L Duchene, Anne-Marie Habraken, Robertt A.F. Valente and Ricardo J Alves de Sousa
Numerical simulation of the single point incremental forming (SPIF) processes can be very demanding and time consuming due to the constantly changing contact conditions between…
Abstract
Purpose
Numerical simulation of the single point incremental forming (SPIF) processes can be very demanding and time consuming due to the constantly changing contact conditions between the tool and the sheet surface, as well as the nonlinear material behaviour combined with non-monotonic strain paths. The purpose of this paper is to propose an adaptive remeshing technique implemented in the in-house implicit finite element code LAGAMINE, to reduce the simulation time. This remeshing technique automatically refines only a portion of the sheet mesh in vicinity of the tool, therefore following the tool motion. As a result, refined meshes are avoided and consequently the total CPU time can be drastically reduced.
Design/methodology/approach
SPIF is a dieless manufacturing process in which a sheet is deformed by using a tool with a spherical tip. This dieless feature makes the process appropriate for rapid-prototyping and allows for an innovative possibility to reduce overall costs for small batches, since the process can be performed in a rapid and economic way without expensive tooling. As a consequence, research interest related to SPIF process has been growing over the last years.
Findings
In this work, the proposed automatic refinement technique is applied within a reduced enhanced solid-shell framework to further improve numerical efficiency. In this sense, the use of a hexahedral finite element allows the possibility to use general 3D constitutive laws. Additionally, a direct consideration of thickness variations, double-sided contact conditions and evaluation of all components of the stress field are available with solid-shell and not with shell elements. Additionally, validations by means of benchmarks are carried out, with comparisons against experimental results.
Originality/value
It is worth noting that no previous work has been carried out using remeshing strategies combined with hexahedral elements in order to improve the computational efficiency resorting to an implicit scheme, which makes this work innovative. Finally, it has been shown that it is possible to perform accurate and efficient finite element simulations of SPIF process, resorting to implicit analysis and continuum elements. This is definitively a step-forward on the state-of-art in this field.
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Stéphane Becuwe and Bertrand Blancheton
The principle of tariffs dispersion, or differential tariffs depending on country of origin, is well known. For instance, Canada adapted a double column of tariffs after 1846…
Abstract
The principle of tariffs dispersion, or differential tariffs depending on country of origin, is well known. For instance, Canada adapted a double column of tariffs after 1846, Spain in 1877, and Switzerland in the 1880–1890s. But there has never before been a comprehensive measure for any national economy, to our knowledge. This contribution proposes an original and exhaustive measure of customs tariffs dispersion depending on the origin of imported products for France between 1850 and 1913. Part of this dispersion arises indirectly as the result of compiling the nomenclature – or the schedule of categories – for France’s general trade chart. Our study nevertheless reveals the existence of direct discriminatory practices applied to certain countries for certain products. The creation of this measure yields important insights. First, tariff dispersion’s evolution completes the analysis of the chronology of trade policy. Second, it is possible to link tariff discrimination, imports in particular sectors, and national production. In our opinion, the paper should pave the way to work that reintroduces a country-specific dimension into the study of late 19th century commercial policy.
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Sheet metal forming is a process of shaping thin sheets of metal by applying pressure through male or female dies or both. In most of used sheet‐formating processes the metal is…
Abstract
Sheet metal forming is a process of shaping thin sheets of metal by applying pressure through male or female dies or both. In most of used sheet‐formating processes the metal is subjected to primarily tensile or compressive stresses or both. During the last three decades considerable advances have been made in the applications of numerical techniques, especially the finite element methods, to analyze physical phenomena in the field of structural, solid and fluid mechanics as well as to simulate various processes in engineering. These methods are useful because one can use them to find out facts or study the processes in a way that no other tool can accomplish. Finite element methods applied to sheet metal forming are the subjects of this paper. The reason for writing this bibliography is to save time for readers looking for information dealing with sheet metal forming, not having an access to large databases or willingness to spend own time with uncertain information retrieval. This paper is organized into two parts. In the first one, each topic is handled and current trends in the application of finite element techniques are briefly mentioned. The second part, an Appendix, lists papers published in the open literature. More than 900 references to papers, conference proceedings and theses/dissertations dealing with subjects that were published in 1995‐2003 are listed.
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To provide a selective bibliography for researchers working with bulk material forming (specifically the forging, rolling, extrusion and drawing processes) with sources which can…
Abstract
Purpose
To provide a selective bibliography for researchers working with bulk material forming (specifically the forging, rolling, extrusion and drawing processes) with sources which can help them to be up‐to‐date.
Design/methodology/approach
A range of published (1996‐2005) works, which aims to provide theoretical as well as practical information on the material processing namely bulk material forming. Bulk deformation processes used in practice change the shape of the workpiece by plastic deformations under forces applied by tools and dies.
Findings
Provides information about each source, indicating what can be found there. Listed references contain journal papers, conference proceedings and theses/dissertations on the subject.
Research limitations/implications
It is an exhaustive list of papers (1,693 references are listed) but some papers may be omitted. The emphasis is to present papers written in English language. Sheet material forming processes are not included.
Practical implications
A very useful source of information for theoretical and practical researchers in computational material forming as well as in academia or for those who have recently obtained a position in this field.
Originality/value
There are not many bibliographies published in this field of engineering. This paper offers help to experts and individuals interested in computational analyses and simulations of material forming processes.
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Usman Tariq, Ranjit Joy, Sung-Heng Wu, Muhammad Arif Mahmood, Asad Waqar Malik and Frank Liou
This study aims to discuss the state-of-the-art digital factory (DF) development combining digital twins (DTs), sensing devices, laser additive manufacturing (LAM) and subtractive…
Abstract
Purpose
This study aims to discuss the state-of-the-art digital factory (DF) development combining digital twins (DTs), sensing devices, laser additive manufacturing (LAM) and subtractive manufacturing (SM) processes. The current shortcomings and outlook of the DF also have been highlighted. A DF is a state-of-the-art manufacturing facility that uses innovative technologies, including automation, artificial intelligence (AI), the Internet of Things, additive manufacturing (AM), SM, hybrid manufacturing (HM), sensors for real-time feedback and control, and a DT, to streamline and improve manufacturing operations.
Design/methodology/approach
This study presents a novel perspective on DF development using laser-based AM, SM, sensors and DTs. Recent developments in laser-based AM, SM, sensors and DTs have been compiled. This study has been developed using systematic reviews and meta-analyses (PRISMA) guidelines, discussing literature on the DTs for laser-based AM, particularly laser powder bed fusion and direct energy deposition, in-situ monitoring and control equipment, SM and HM. The principal goal of this study is to highlight the aspects of DF and its development using existing techniques.
Findings
A comprehensive literature review finds a substantial lack of complete techniques that incorporate cyber-physical systems, advanced data analytics, AI, standardized interoperability, human–machine cooperation and scalable adaptability. The suggested DF effectively fills this void by integrating cyber-physical system components, including DT, AM, SM and sensors into the manufacturing process. Using sophisticated data analytics and AI algorithms, the DF facilitates real-time data analysis, predictive maintenance, quality control and optimal resource allocation. In addition, the suggested DF ensures interoperability between diverse devices and systems by emphasizing standardized communication protocols and interfaces. The modular and adaptable architecture of the DF enables scalability and adaptation, allowing for rapid reaction to market conditions.
Originality/value
Based on the need of DF, this review presents a comprehensive approach to DF development using DTs, sensing devices, LAM and SM processes and provides current progress in this domain.
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Aditi Agrawal, Rayah Touma Sawaya, Margaret Ojeahere, Vanessa Padilla and Samer El Hayek
This study aims to review the presentation of substance use disorders in older adults, how addiction intertwines with neurocognitive disorders and how to approach this vulnerable…
Abstract
Purpose
This study aims to review the presentation of substance use disorders in older adults, how addiction intertwines with neurocognitive disorders and how to approach this vulnerable population.
Design/methodology/approach
Electronic data searches of PubMed, Medline and the Cochrane Library (years 2000–2021) were performed using the keywords “neurocognitive,” “dementia,” “substance use,” “addiction,” “older adults” and “elderly.” The authors, in consensus, selected pivotal studies and conducted a narrative synthesis of the findings.
Findings
Research about substance use disorders in older adults is limited, especially in those with superimposed neurocognitive disorders. Having dual diagnoses can make the identification and treatment of either condition challenging. Management should use a holistic multidisciplinary approach that involves medical professionals and caregivers.
Originality/value
This review highlights some of the intertwining aspects between substance use disorders and neurocognitive disorders in older adults. It provides a comprehensive summary of the available evidence on treatment in this population.
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Constance L Coogle and Myra G Owens
In recent years, Screening and Brief Intervention (SBI) has become increasingly available to older adults who engage in at-risk drinking behaviors. The results of SBI training…
Abstract
Purpose
In recent years, Screening and Brief Intervention (SBI) has become increasingly available to older adults who engage in at-risk drinking behaviors. The results of SBI training sessions that targeted hospital-based healthcare providers, as well as mental health service providers in community-based clinics, are reported. The paper aims to discuss these issues.
Design/methodology/approach
In total, 93 participants attended SBI active learning training sessions. The responses of physicians/physicians in training about their intentions to apply the information in professional practice and their willingness to recommend the training to others in their profession were compared to practitioners in other professions.
Findings
Although there were no differences in terms of commitment to apply the information or level of comfort using the techniques, physicians/physicians in training were less interested in promoting the SBI training among their colleagues.
Research limitations/implications
The results are limited with respect to the number of training participants engaged and the geography entailed, yet implications for addressing barriers to widespread implementation and training challenges are explored.
Practical implications
Although it may be more difficult to promote SBI training in locations that do not primarily provide mental health services, hospitals, and other primary care settings are precisely where training may be most useful.
Social implications
The importance of training approaches to SBI that are disseminated within the context of a public health model of clinical preventive services is highlighted.
Originality/value
Original research is presented to highlight the need to improve training receptivity and facilitate the translation into practice.
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Beatriz Picazo Rodríguez, Antonio Jose Verdú-Jover, Marina Estrada-Cruz and Jose Maria Gomez-Gras
To understand how organizations, public or private, must increase their productivity perception (PP), independently of the sector. This article aims to analyze PP in the digital…
Abstract
Purpose
To understand how organizations, public or private, must increase their productivity perception (PP), independently of the sector. This article aims to analyze PP in the digital transformation (DT) process to determine how it is affected by technostress (TS) and work engagement (WE), two concepts that seem to be forces opposing PP.
Design/methodology/approach
The authors use data from a questionnaire addressed to personnel in two organizations (public and private). The analysis applies partial least squares technique to the 505 valid responses obtained from these organizations. This analysis is based not on representativeness but on uniqueness.
Findings
The results suggest a positive, significant relationship between DT and PP. This article integrates DT and its effects on aspects of people's health, PP and WE. The model thus includes interactions of technology with human elements. In both business and administrative environments, PP is key to optimizing resources and survival of organizations.
Research limitations/implications
DT processes are different and complex because every organization is different. The authors recommend expanding this study to other sectors in both spheres, public and private. Aligning the objectives of the institutions for aid with DT is also quite complicated.
Practical implications
This study contributes to improving participating organizations. It also provides government institutions with a clear foundation from which to encourage actions that promote the health and WE of their workforce without reducing productivity. In addition, this study adds novelty to the research line.
Originality/value
The authors have deepened this line of research by developing fuller knowledge of the relationships among novel and necessary variables in organizations. The authors provide complementary, different and inspiring value in addressing this line of research.
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Ashlee Curtis, Keith McVilly and Andrew Day
The purpose of this paper is to identify and evaluate treatment for adult fire setters with an intellectual disability, given the specific risks they present, the complexities of…
Abstract
Purpose
The purpose of this paper is to identify and evaluate treatment for adult fire setters with an intellectual disability, given the specific risks they present, the complexities of criminal proceedings associated with their behaviour, and subsequent rehabilitation. However, the review also took into account programmes for fire setters in the wider population, including those for children and adolescents, given that such research might also inform the development of programmes for offenders with an intellectual disability.
Design/methodology/approach
A systematic review of the literature was undertaken.
Findings
Only four studies which evaluated treatment programmes specifically for arsonists with an intellectual disability were identified. Although each of these studies reported a reduction in fire‐setting behaviour following programme completion, all employed relatively weak research designs. An additional 12 studies investigating programmes for arsonists without intellectual disability were also identified. It is concluded that there is a lack of evidence regarding treatment programme outcomes for arsonists with an intellectual disability. The extent to which such programmes can be adapted to suit adult offenders with an intellectual disability is discussed, with recommendations made for the design and evaluation of arson treatment programmes for offenders with intellectual disabilities.
Originality/value
Currently, minimal treatments programs exist for fire setting in offenders with intellectual disability. This review highlights the importance of further research into treatment programs for this specialised population.
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J.I.V. Sena, R.J. Alves de Sousa and R.A.F. Valente
Incremental sheet forming represents a promising process in the manufacturing of metallic components, particularly its variant known as single point incremental forming (SPIF)…
Abstract
Purpose
Incremental sheet forming represents a promising process in the manufacturing of metallic components, particularly its variant known as single point incremental forming (SPIF). The purpose of this paper is to test and validate the results coming from numerical simulation of SPIF processes using the reduced enhanced solid‐shell formulation, when compared to the solid finite elements available in ABAQUS software. The use of SPIF techniques in the production of small batch components has a potential wide application in fields such as rapid prototyping and biomechanical devices.
Design/methodology/approach
Incremental forming processes differ from conventional stamping by not using a press and by requiring a lower number of tools, since no dedicated punches and dies are necessary, which lowers the overall production costs. In addition, it shows relative simplicity and flexible setup for complex parts, when compared with conventional technologies. However, the low speed of production and low‐dimensional accuracy levels are still the main obstacles for a wider application of this technique in the context of large production batches.
Findings
In this sense, the use of numerical simulation tools based on the finite element method (FEM) can provide a better understanding of the process' peculiarities. However, there are differences on using distinct finite element formulations, regarding accuracy as well as CPU times during simulations, which can be prohibitive in some cases.
Originality/value
Aiming to provide sounding improvements in these two fields (robustness and cost effectiveness of FEM solutions), the present work encloses a preliminary study about some relevant parameters in the FEM simulation of SPIF. Special focus is given to the use of solid‐shell and solid finite elements, for the sake of generality in modelling, as well as implicit solution schemes for the sake of accuracy. Finally, results coming from both experimental data and commercial FEM packages are compared to those obtained by a reliable and cost‐effective solid‐shell finite element formulation developed and implemented by the authors.
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