Search results

1 – 10 of over 1000
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 1 April 1981

Peter J. Neagle and Thomas D. Newton

In attempts to meet the need for low‐loss materials capable of attaining the dielectric properties that are required for rapidly developing microwave and high speed digital…

22

Abstract

In attempts to meet the need for low‐loss materials capable of attaining the dielectric properties that are required for rapidly developing microwave and high speed digital equipment, polysulphone in its various forms has been undergoing investigation. Microwave dielectric properties are examined with respect to temperature and frequency, and three types of polysulphone are studied in depth, with testing for dielectric constant and dissipation factor. The material's physical properties are listed prior to advisory comments on special processing requirements. Its feasibility in multilayer production is currently being researched.

Details

Circuit World, vol. 8 no. 1
Type: Research Article
ISSN: 0305-6120

Access Restricted. View access options
Article
Publication date: 15 November 2011

Xi Chen and Yong‐Gang Cheng

The initial stiffness method has been extensively adopted for elasto‐plastic finite element analysis. The main problem associated with the initial stiffness method, however, is…

253

Abstract

Purpose

The initial stiffness method has been extensively adopted for elasto‐plastic finite element analysis. The main problem associated with the initial stiffness method, however, is its slow convergence, even when it is used in conjunction with acceleration techniques. The Newton‐Raphson method has a rapid convergence rate, but its implementation resorts to non‐symmetric linear solvers, and hence the memory requirement may be high. The purpose of this paper is to develop more advanced solution techniques which may overcome the above problems associated with the initial stiffness method and the Newton‐Raphson method.

Design/methodology/approach

In this work, the accelerated symmetric stiffness matrix methods, which cover the accelerated initial stiffness methods as special cases, are proposed for non‐associated plasticity. Within the computational framework for the accelerated symmetric stiffness matrix techniques, some symmetric stiffness matrix candidates are investigated and evaluated.

Findings

Numerical results indicate that for the accelerated symmetric stiffness methods, the elasto‐plastic constitutive matrix, which is constructed by mapping the yield surface of the equivalent material to the plastic potential surface, appears to be appealing. Even when combined with the Krylov iterative solver using a loose convergence criterion, they may still provide good nonlinear convergence rates.

Originality/value

Compared to the work by Sloan et al., the novelty of this study is that a symmetric stiffness matrix is proposed to be used in conjunction with acceleration schemes and it is shown to be more appealing; it is assembled from the elasto‐plastic constitutive matrix by mapping the yield surface of the equivalent material to the plastic potential surface. The advantage of combining the proposed accelerated symmetric stiffness techniques with the Krylov subspace iterative methods for large‐scale applications is also emphasized.

Access Restricted. View access options
Article
Publication date: 1 June 1994

P.R. Masani

Presents the scientific methodology from the enlarged cybernetical perspective that recognizes the anisotropy of time, the probabilistic character of natural laws, and the entry…

821

Abstract

Presents the scientific methodology from the enlarged cybernetical perspective that recognizes the anisotropy of time, the probabilistic character of natural laws, and the entry that the incomplete determinism in Nature opens to the occurrence of innovation, growth, organization, teleology communication, control, contest and freedom. The new tier to the methodological edifice that cybernetics provides stands on the earlier tiers, which go back to the Ionians (c. 500 BC). However, the new insights reveal flaws in the earlier tiers, and their removal strengthens the entire edifice. The new concepts of teleological activity and contest allow the clear demarcation of the military sciences as those whose subject matter is teleological activity involving contest. The paramount question “what ought to be done”, outside the empirical realm, is embraced by the scientific methodology. It also embraces the cognitive sciences that ask how the human mind is able to discover, and how the sequence of discoveries might converge to a true description of reality.

Details

Kybernetes, vol. 23 no. 4
Type: Research Article
ISSN: 0368-492X

Keywords

Access Restricted. View access options
Article
Publication date: 1 January 1954

Aarhus Kommunes Biblioteker (Teknisk Bibliotek), Ingerslevs Plads 7, Aarhus, Denmark. Representative: V. NEDERGAARD PEDERSEN (Librarian).

120

Abstract

Aarhus Kommunes Biblioteker (Teknisk Bibliotek), Ingerslevs Plads 7, Aarhus, Denmark. Representative: V. NEDERGAARD PEDERSEN (Librarian).

Details

Aslib Proceedings, vol. 6 no. 1
Type: Research Article
ISSN: 0001-253X

Access Restricted. View access options
Article
Publication date: 2 May 2017

Guillaume Caron, Thomas Henneron, Francis Piriou and Jean-Claude Mipo

The purpose of this study is to determine the steady state of an electromagnetic structure using the finite element method (FEM) without calculation of the transient state. The…

78

Abstract

Purpose

The purpose of this study is to determine the steady state of an electromagnetic structure using the finite element method (FEM) without calculation of the transient state. The proposed method permits to reduce the computation time if the transient state is important.

Design/methodology/approach

In the case of coupling magnetic and electric circuit equations to obtain the steady state with periodic conditions, an approach can be to discretise the time with periodic conditions and to solve the equation system. Unfortunately, the computation time can be prohibitive. In this paper, the authors proposed to use the waveform relaxation method associated with the Newton method to accelerate the convergence.

Findings

The obtained results show that the proposed approach is efficient if the transient state is important. On the contrary, if the transient state is very low, it is preferable to use the classical approach, namely, the time-stepping FEM.

Research limitations/implications

The main limitation of the proposed approach is the necessity to evaluate or to know the time constant and consequently the duration of the transient state. Moreover the method requires some important memory resources.

Practical/implications

In the context of the use of the time-stepping FEM, one of the problems is the computation time which can be important to obtain the steady state. The proposed method permits avoidance of this difficulty and directly gives the steady state.

Social/implications

The proposed approach will permit to model and study the electromagnetic systems in the steady state, and particularly the transformers. Because of the gain in computing time, the use of optimisation techniques will be facilitated.

Originality/value

The novelty of this study is the proposal of the waveform relaxation–Newton method to directly obtain the steady state when applied to the three-phase transformer.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Access Restricted. View access options
Article
Publication date: 1 June 2001

Irina Munteanu, Silvia Drobny, Thomas Weiland and Daniel Ioan

This paper presents a hybrid algorithm used, in conjunction with the Finite Integration Technique (FIT), for solving static and quasistatic electromagnetic field problems in…

324

Abstract

This paper presents a hybrid algorithm used, in conjunction with the Finite Integration Technique (FIT), for solving static and quasistatic electromagnetic field problems in nonlinear media. The hybrid technique is based on new theoretical results regarding the similarities between the Picard‐Banach fixed‐point (polarization) method and the Newton method. At each iteration, the solution is obtained as a linear combination of the old solution, and the new Picard‐Banach and Newton solutions. The numerical solutions are calculated through a “triangle” (bidimensional) minimization of the residual or of the energy functional. The goal of this combination is to increase the robustness of the iterative method, without losing the quadratic speed of convergence in the vicinity of the solution. The proposed method generalizes and unifies in a single algorithm the overrelaxed Picard‐Banach and the underrelaxed Newton methods.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 20 no. 2
Type: Research Article
ISSN: 0332-1649

Keywords

Access Restricted. View access options
Article
Publication date: 26 August 2024

Thomas Ellis and Vic Newton

Previous research has evidenced that communication design students wish to engage further with sustainable practices but struggle to understand how (Newton and Ellis, HER…

49

Abstract

Purpose

Previous research has evidenced that communication design students wish to engage further with sustainable practices but struggle to understand how (Newton and Ellis, HER conference 2023). Whereas other design disciplines (fashion, product, furniture) can often focus on a “physical” output, communication design embraces multiple outcomes, distributed throughout a range of platforms, representing an area of industry and study which can prove difficult to define. This study aims to add further clarity as to how students consider sustainability aligned to their practice.

Design/methodology/approach

Previous focus group research sought to uncover how communication design students implicitly consider “sustainability”, uncovering that their knowledge is limited. Suggestions from participants emphasised that it was the role of the institution, not the student, to fully integrate sustainability into practice and to define methods they can deploy. This paper notes a subsequent workshop conducted with 33 Level 5 undergraduate students asking them to reflect on Sustainable Development Goals (SDGs) 12/13 in relation to meaningful practice and institutional responsibility.

Findings

Workshops demonstrated the need to engage with sustainable thinking throughout every stage of development. It is clear that students demand more from academic staff at programme level, and from the institution at large, to provide further solutions to sustainability concerns which are relevant to their specific practice.

Originality/value

Discussion surrounding pedagogical practice across communication design lacks interrogation, yet the discipline represents a significant aspect of both design and contemporary society. It is paramount that methods for reinforcing implicit engagement with sustainable best practice within students, their development and their future beyond university are therefore developed.

Details

International Journal of Sustainability in Higher Education, vol. 25 no. 7
Type: Research Article
ISSN: 1467-6370

Keywords

Access Restricted. View access options
Book part
Publication date: 24 July 2020

Soo-Hoon Lee, Thomas W. Lee and Phillip H. Phan

Workplace voice is well-established and encompasses behaviors such as prosocial voice, informal complaints, grievance filing, and whistleblowing, and it focuses on interactions…

Abstract

Workplace voice is well-established and encompasses behaviors such as prosocial voice, informal complaints, grievance filing, and whistleblowing, and it focuses on interactions between the employee and supervisor or the employee and the organizational collective. In contrast, our chapter focuses on employee prosocial advocacy voice (PAV), which the authors define as prosocial voice behaviors aimed at preventing harm or promoting constructive changes by advocating on behalf of others. In the context of a healthcare organization, low quality and unsafe patient care are salient and objectionable states in which voice can motivate actions on behalf of the patient to improve information exchanges, governance, and outreach activities for safer outcomes. The authors draw from the theory and research on responsibility to intersect with theories on information processing, accountability, and stakeholders that operate through voice between the employee-patient, employee-coworker, and employee-profession, respectively, to propose a model of PAV in patient-centered healthcare. The authors complete the model by suggesting intervening influences and barriers to PAV that may affect patient-centered outcomes.

Details

Research in Personnel and Human Resources Management
Type: Book
ISBN: 978-1-80043-076-1

Keywords

Access Restricted. View access options
Article
Publication date: 1 December 1913

In October, 1908, a report was issued by the Medical Officer of Health for the City of London relating to the unsatisfactory manner in which soda water was manufactured at that…

29

Abstract

In October, 1908, a report was issued by the Medical Officer of Health for the City of London relating to the unsatisfactory manner in which soda water was manufactured at that time in the London district, and to the means that had been used after official enquiry to better the methods of manufacture. The circumstances were referred to in this Journal for November, 1908. It will be remembered that at the time reputable members of the trade readily agreed that they should be bound by certain regulations. These regulations had been drawn up by the Medical Officer of Health for the City of London and related to inspection of premises and examination of plant, water, and materials. As a proof that they had complied with the regulations a certificate was issued to each firm by their trade society, “The London Bottle Exchange and Mineral Water Trade Protection Society, Limited.” This certificate was submitted to and passed by the Medical Officer of Health for the City of London before issue. The arrangement, though good in conception, appears to be faulty in design, and it is desirable, therefore, to offer some criticism.

Details

British Food Journal, vol. 15 no. 12
Type: Research Article
ISSN: 0007-070X

Access Restricted. View access options
Article
Publication date: 1 June 2002

Barrie O. Pettman and Richard Dobbins

This issue is a selected bibliography covering the subject of leadership.

29854

Abstract

This issue is a selected bibliography covering the subject of leadership.

Details

Equal Opportunities International, vol. 21 no. 4/5/6
Type: Research Article
ISSN: 0261-0159

Keywords

1 – 10 of over 1000
Per page
102050