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1 – 10 of 16Zuqi Tang, Yvonnick Le-menach, E. Creusé, S. Nicaise, F. Piriou and N. Némitz
The purpose of this paper is to propose some a posteriori residual error estimators (REEs)to evaluate the accuracy of the finite element method for quasi-static electromagnetic…
Abstract
Purpose
The purpose of this paper is to propose some a posteriori residual error estimators (REEs)to evaluate the accuracy of the finite element method for quasi-static electromagnetic problems with mixed boundary conditions. Both classical magnetodynamic A-ϕ and T-Ω formulations in harmonic case are analysed. As an example of application the estimated error maps of an electromagnetic system are studied. At last, a remeshing process is done according to the estimated error maps.
Design/methodology/approach
The paper proposes to analyze the efficiency of numerical REEs in the case of magnetodynamic harmonic formulations. The deal is to determine the areas where it is necessary to improve the mesh. Moreover the error estimators are applied for structures with mixed boundary conditions.
Findings
The studied application shows the possibilities of the residual error estimators in the case of electromagnetic structures. The comparison of the remeshed show the improvement of the obtained solution when the authors compare with a reference one.
Research limitations/implications
The paper provides some interesting results in the case of magnetodynamic harmonic formulations in terms of potentials. Both classical formulations are studied.
Practical implications
The paper provides some informations to develop the proposed formulations in the software using finite element method.
Social implications
The paper deals with the possibility to improve the determination of the meshes in the analysis of electromagnetic structure with the finite element method. The proposed method can be a good solution to obtain an optimal mesh for a given numerical error.
Originality/value
The paper proposes some elements of solution for the numerical analysis of electromagnetic structures. More particularly the results can be used to determine the good meshes of the finite element method.
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Antoine Alexandre Journeaux, Nicolas Nemitz and Olivier Moreau
– This article presents a locally conservative projection method which aims to preserve the integral of a function and one operator among grad, div, or curl.
Abstract
Purpose
This article presents a locally conservative projection method which aims to preserve the integral of a function and one operator among grad, div, or curl.
Design/methodology/approach
After a theoretical description of the projection methods, the locally conservative projection is analytically tested and compared with the orthogonal method. In the second part, the implementation of the methods is described, and improvements are proposed. An industrial application of the present work, consisting in a magneto-thermal coupled problem, is then presented.
Findings
The implementation of the conservative method is simpler than the implementation of the orthogonal method while presenting similar behaviour in terms of accuracy and conservation.
Originality/value
The locally conservative method is extended to curl-conform and div-conform elements. Furthermore, three-dimensional studies are proposed.
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Zuqi Tang, Yvonnick Le Menach, Emmanuel Creuse, Serge Nicaise, Francis Piriou and Nicolas Nemitz
In this paper, the aim is to propose a residual‐based error estimator to evaluate the numerical error induced by the computation of the electromagnetic systems using a finite…
Abstract
Purpose
In this paper, the aim is to propose a residual‐based error estimator to evaluate the numerical error induced by the computation of the electromagnetic systems using a finite element method in the case of the harmonic A‐φ formulation.
Design/methodology/approach
The residual based error estimator used in this paper verifies the mathematical property of global and local error estimation (reliability and efficiency).
Findings
This estimator used is based on the evaluation of quantities weakly verified in the case of harmonic A‐φ formulation.
Originality/value
In this paper, it is shown that the proposed estimator, based on the mathematical developments, is hardness in the case of the typical applications.
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Van Quang Dinh and Yves Marechal
In FEM computations, the mesh quality improves the accuracy of the approximation solution and reduces the computation time. The dynamic bubble system meshing technique can provide…
Abstract
Purpose
In FEM computations, the mesh quality improves the accuracy of the approximation solution and reduces the computation time. The dynamic bubble system meshing technique can provide high-quality meshes, but the packing process is time-consuming. This paper aims to improve the running time of the bubble meshing by using the advantages of parallel computing on graphics processing unit (GPU).
Design/methodology/approach
This paper is based on the analysis of the processing time on CPU. A massively parallel computing-based CUDA architecture is proposed to improve the bubble displacement and database updating. Constraints linked to hardware considerations are taken into account. Finally, speedup factors are provided on test cases and real scale examples.
Findings
The numerical experiences show the efficiency of parallel performance reaches a speedup of 35 compared to the serial implementation.
Research limitations/implications
This contribution is so far limited to two-dimensional (2D) geometries although the extension to three-dimension (3D) is straightforward regarding the meshing technique itself and the GPU implementation. The authors’ works are based on a CUDA environment which is widely used by developers. C\C++ and Java were the programming languages used. Other languages may of course lead to slightly different implementations.
Practical implications
This approach makes it possible to use bubble meshing technique for both initial design and optimization, as excellent meshes can be built in few seconds.
Originality/value
Compared to previous works, this contribution shows that the scalability of the bubble meshing technique needs to solve two key issues: reach a T(N) global cost of the implementation and reach a very fast size map interpolation strategy.
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Drawing on his personal experience as a police officer and a range of literature, the author applies Caulkins' and Reuter's paper in this edition to the UK experience. In…
Abstract
Drawing on his personal experience as a police officer and a range of literature, the author applies Caulkins' and Reuter's paper in this edition to the UK experience. In particular he draws on the work of Goldstein, which places drug‐related crime into three categories: psychopharmacological, economic‐compulsive and systemic.
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The goal of this article is to introduce the notion of a grey relation between grey sets using grey numbers.
Abstract
Purpose
The goal of this article is to introduce the notion of a grey relation between grey sets using grey numbers.
Design/methodology/approach
This study uses the grey number to create novel ideas of grey sets. We suggest several operations that can be performed on it, including the union, intersection, join, merge, and composition of grey relations. In addition, we present the definitions of reflexive, symmetric, and transitive grey relations and analyze certain characteristics associated with them. Furthermore, we formulate the concept of the grey equivalence relation, apply it to the study of the grey equivalence class over the grey relation, and go over some of its features.
Findings
We present new algebraic aspects of grey system theory by defining grey relations and then analyzing their characteristic features.
Practical implications
This paper proposes a new theoretical direction for grey sets according to grey numbers, namely, grey relations. This paper proposes a new theoretical direction for grey sets according to grey numbers, namely, grey relations. As such, it can be applied to create rough approximations as well as congruences in algebras, topologies, and semigroups.
Originality/value
The presented notions are regarded as new algebraic approaches in grey system theory for the first time. Additionally, some fundamental operations on grey relations are also investigated. Consequently, different types of grey relations, such as reflexive, symmetric, and transitive relations, are discussed. Then, the grey equivalence class derived from the grey equivalence relation is demonstrated, and its properties are examined.
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This research study aims to explore the trends in the use of appropriate adults (AAs) for persons with mental disabilities (PMDs) during law enforcement investigation interviews…
Abstract
Purpose
This research study aims to explore the trends in the use of appropriate adults (AAs) for persons with mental disabilities (PMDs) during law enforcement investigation interviews in Singapore and examine the profile of PMDs who were supported by AAs through the investigation process. AAs play a vital role in facilitating communication and providing emotional support to PMDs during investigation interviews.
Design/methodology/approach
A descriptive analysis was conducted on data collected from 2016 to 2019.
Findings
The findings of the study indicate a growing demand for AA services to support PMDs with some variations across different geographical regions. Approximately three-quarters of all completed interviews supported PMDs who were suspects/accused. Interviewees who received AA support were largely Chinese, male, in their adolescent or early adulthood years and had an intellectual disability. More than half of the interviews supported by AAs involved offences that were sexual in nature or property related.
Originality/value
These results reflect a growing awareness of the role and importance of AAs for PMDs and have practical implications on service delivery and development. This paper’s findings on the profile of PMDs supported by AAs also set the groundwork for further research to investigate how PMDs interface with the criminal justice system.
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Iain McKinnon, Julie Thorp and Don Grubin
The purpose of this paper is twofold. First to ascertain the efficacy of current police reception screening to detect detainees with intellectual disability (ID). Second to assess…
Abstract
Purpose
The purpose of this paper is twofold. First to ascertain the efficacy of current police reception screening to detect detainees with intellectual disability (ID). Second to assess the validity of a short targeted screen for ID among police custody detainees.
Design/methodology/approach
The study comprised three stages. First, 248 police custody detainees were assessed for a range of health morbidities, including a pragmatic clinical evaluation of ID. For those with suspected ID, the police custody screens were scrutinised for evidence that this had been detected. Second, a new police health screen, incorporating a short screen for ID, was piloted. Totally, 351 detainees were assessed in the same way as in part 1 with the new screens being scrutinised for evidence that ID had been detected where relevant. Third, the new police screen for ID was validated among a sample of 64 inpatients, some with ID and some without, from forensic inpatient services. Parts 1 and 2 were carried out in the Metropolitan Police Service, London. Part 3 took place in one NHS Trust.
Findings
In parts 1 and 2, the rate of detainees with suspected ID was 2-3 per cent. The standard police screen detected 25 per cent of these detainees in part 1. When the new screen was introduced in part 2, the sensitivity for ID increased to 83 per cent. However, there was no requisite improvement in the proportion of detainees with ID receiving an Appropriate Adult. In the inpatient study, the new screen showed a good level of sensitivity (91 per cent) and reasonable specificity (63 per cent).
Practical implications
It is possible to improve the detection rate of detainees with suspected ID by introducing a short ID screen into the police custody officers’ reception health screen.
Originality/value
The Health Screening of People in Police Custody (HELP-PC) study is a project evaluating screening for health morbidity among police custody detainees. Other data from this study have been reported elsewhere, but this is the first time the data pertaining to ID screening has been reported in detail.
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Raíssa Mendes Tomaz and Jerzui Mendes Torres Tomaz
The purpose of this paper selected by ICIL 2019 committee in Rome is to demonstrate the current importance of the internet in the protection of democracy in developting countries.
Abstract
Purpose
The purpose of this paper selected by ICIL 2019 committee in Rome is to demonstrate the current importance of the internet in the protection of democracy in developting countries.
Design/methodology/approach
It is intended to make a comparison with the growing and current phenomenon of Brazilian disinformation with other contemporary phenomena related to new technologies through literature review methodology.
Findings
The Brazilian elections in 2018 represent an authentic model in a post-Cambridge Analytical phase where the myth of the sanctity of data has been broken. The big influence of the algorithmic revolution on democracies in Latin America has never been more evident. The misuse of algorithms created an artificial environment that does not put us in contact with different realities; the consequences of this conjuncture have the deepest impacts, especially in countries that rely on a deficient educational system.
Social implications
Besides that, the broad use of zero-rating on the internet delivery in developing countries is also considered a factor of fake news dissemination. The information bubbles promote political polarization to the detriment of diversity – and the diversity is par excellence one of the pillars of democracy.
Originality/value
The research about the impact that the phenomenon of disinformation has on underdeveloped countries, it is essential to analyze the new role of the legislator in the elaboration of hypercomplex laws with multi-stakeholder interests that respect the essential core of digital human rights as the freedom of expression online.
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Daniel Silva, Karen Gough and Hannah Weeks
At present, there are significant limitations to the criminal justice system’s (CJS) ability to respond appropriately to detainees or defendant with learning disabilities (LD)…
Abstract
Purpose
At present, there are significant limitations to the criminal justice system’s (CJS) ability to respond appropriately to detainees or defendant with learning disabilities (LD). The development of Liaison and Diversion Services has provided the opportunity to more easily identify people with LD in the CJS through the use of screening assessments. Therefore, the purpose of this paper is to consider why there is a need for screening assessments and review the literature on existing measures, in order to consider the next steps to develop a more effective pathway from the CJS to LD services.
Design/methodology/approach
This paper takes the form of a literature review.
Findings
The review found that there is a significant body of research defending the need for LD screening in the CJS across the UK. The aim of a screening process would be to identify individuals who possibly have LD and ensure that the correct measures are in place to assess and manage these individuals, including appropriate diversion to specialist LD services. The learning disability screening questionnaire (LDSQ) is an instrument that could be utilised in these instances and could be carried out by Liaison and Diversion Services.
Research limitations/implications
Neither of the tools reviewed in this paper have been vigorously field tested within forensic settings in the UK. It is recommended that there should be trials of the LDSQ as a screening tool within Liaison and Diversion Services with comparison against outcomes of full diagnostic assessments for LD.
Originality/value
Screening for LD is being discussed across the UK as part of Liaison and Diversion Services. This paper highlights the need for a reliable and valid screening tool and provides support for the use of the LDSQ.
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