R. DE BORST, L.J. SLUYS, H.‐B. MUHLHAUS and J. PAMIN
Classical continuum models, i.e. continuum models that do not incorporate an internal length scale, suffer from excessive mesh dependence when strain‐softening models are used in…
Abstract
Classical continuum models, i.e. continuum models that do not incorporate an internal length scale, suffer from excessive mesh dependence when strain‐softening models are used in numerical analyses and cannot reproduce the size effect commonly observed in quasi‐brittle failure. In this contribution three different approaches will be scrutinized which may be used to remedy these two intimately related deficiencies of the classical theory, namely (i) the addition of higher‐order deformation gradients, (ii) the use of micropolar continuum models, and (iii) the addition of rate dependence. By means of a number of numerical simulations it will be investigated under which conditions these enriched continuum theories permit localization of deformation without losing ellipticity for static problems and hyperbolicity for dynamic problems. For the latter class of problems the crucial role of dispersion in wave propagation in strain‐softening media will also be highlighted.
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Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the…
Abstract
Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.
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The aim of this paper is to extend the Element Free Galerkin method (EFGM) in order to perform the elasto‐plastic analysis of isotropic plates.
Abstract
Purpose
The aim of this paper is to extend the Element Free Galerkin method (EFGM) in order to perform the elasto‐plastic analysis of isotropic plates.
Design/methodology/approach
The EFGM shape‐function construction is briefly presented. The Newton‐Raphson method and the elasto‐plastic algorithm adapted to the EFGM, are described. Several plate bending non‐linear material problems are solved and the obtained solutions are compared with available finite element method (FEM) solutions.
Findings
The paper finds that the developed EFGM approach is a good alternative to the FEM for the solution of non‐linear problems, once the obtained results with the EFGM show a high similarity with the obtained FEM results.
Research limitations/implications
Comparing the FEM and the EFGM there are some drawbacks for the EFGM. The computational cost of the EFGM is higher, the imposition of the essential boundary conditions is more complex and there is a high sensitivity of the method in what concerns the choice of the influence domain and the choice of the weight function.
Practical implications
The knowledge that the EFGM formulation can be treated almost as the FEM formulation once the EFGM parameters are calibrated and optimized.
Originality/value
The extension of the EFGM to the elasto‐plastic analysis of isotropic plates.
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D. Brancherie and A. Ibrahimbegovic
The purpose of this paper is to present a finite element model capable of describing both the diffuse damage mechanism which develops first during the loading of massive brittle…
Abstract
Purpose
The purpose of this paper is to present a finite element model capable of describing both the diffuse damage mechanism which develops first during the loading of massive brittle structures and the failure process, essentially due to the propagation of a macro‐crack responsible for the softening behaviour of the structure. The theoretical developments for such a model are presented, considering an isotropic damage model for the continuum and a Coulomb‐type criterion for the localized part.
Design/methodology/approach
This is achieved by activating subsequently diffuse and localized damage mechanisms. Localized phenomena are taken into account by means of the introduction of a displacement discontinuity at the element level.
Findings
It was found that, with such an approach, the final crack direction is predicted quite well, in fact much better than the prediction made by the fracture mechanics type of models considering combination of only elastic response and softening.
Originality/value
The presented model has the potential to describe complex damage phenomena in a cyclic and/or non‐proportional loading program, such as crack closing and re‐opening, cohesive resistance deterioration due to tangential sliding, by using only a few parameters compared to the traditional models for cyclic loading.
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R. de Borst, G.N. Wells and L.J. Sluys
The formulation of finite elements with incompatible discontinuous modes is examined rigorously. Both weak and strong discontinuities are considered. Starting from a careful…
Abstract
The formulation of finite elements with incompatible discontinuous modes is examined rigorously. Both weak and strong discontinuities are considered. Starting from a careful elaboration of the kinematics for both types of discontinuities a comprehensive finite element formulation is derived based on a three‐field variational statement. Similarities and differences are highlighted between the various formulations which ensue.
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Alice F. Stuhlmacher, Treena L. Gillespie and Matthew V. Champagne
In negotiation, pressures to reach an agreement are assumed to influence both the processes and the outcomes of the discussions. This paper metaanalytically combined different…
Abstract
In negotiation, pressures to reach an agreement are assumed to influence both the processes and the outcomes of the discussions. This paper metaanalytically combined different forms of time pressure to examine its effects on negotiator strategy and impasse rate. High time pressure was more likely to increase negotiator concessions and cooperation than low pressure as well as make agreements more likely. The effect on negotiator strategy, however, was stronger when the deadline was near or when negotiations were simple rather than complex. The effects were weaker when the opponent was inflexible and using a tough negotiation strategy. The effects on cooperative strategies were weaker when incentives for good performance were available than when they were not. Although time pressure in negotiation has significant effects, situational factors play a major role on its impact.
Jan Halvor Natlandsmyr and Jørn Rognes
Previous research on international negotiations has primarily examined cross‐cultural differences in behavioral styles. Supplementing this prior research, we focused on outcome in…
Abstract
Previous research on international negotiations has primarily examined cross‐cultural differences in behavioral styles. Supplementing this prior research, we focused on outcome in negotiations. The study examined relationships between culture and outcome in contract negotiations, and analyzed how negotiation behavior mediates between culture and outcome. Sixty Mexican and Norwegian subjects participated in a negotiation simulation with potentially integrative outcomes. The study included 12 Mexican dyads, 12 Norwegian dyads, and 6 cross‐cultural dyads. Two aspects of outcome: joint benefit and distribution of benefit between negotiators, and two aspects of process: progression of offers and verbal communication, were examined Results indicated an effect of culture on integrative results, but not on distribution of benefit. Process differences found were related to the progression of offers over time, and not to verbal communication. Managerial implications are discussed and directions for future research indicated.
This paper explores the relationship between integrative potential, information exchange, and behavioral and perceptual indicators of negotiation outcome. A measure of integrative…
Abstract
This paper explores the relationship between integrative potential, information exchange, and behavioral and perceptual indicators of negotiation outcome. A measure of integrative potential is introduced that allows the researcher to quantify how much potential for integrativeness is contained in various bargaining scenarios. An experiment using a variant of Pruitt's (1981) bargaining scenario was conducted to investigate the usefulness of the measure. In particular, competitiveness interacted with information exchange to affect joint benefit. It is concluded that integrative potential can help develop useful theories of integrative bargaining.
Tessa Withorn, Jillian Eslami, Hannah Lee, Maggie Clarke, Carolyn Caffrey, Cristina Springfield, Dana Ospina, Anthony Andora, Amalia Castañeda, Alexandra Mitchell, Joanna Messer Kimmitt, Wendolyn Vermeer and Aric Haas
This paper presents recently published resources on library instruction and information literacy, providing an introductory overview and a selected annotated bibliography of…
Abstract
Purpose
This paper presents recently published resources on library instruction and information literacy, providing an introductory overview and a selected annotated bibliography of publications covering various library types, study populations and research contexts.
Design/methodology/approach
This paper introduces and annotates English-language periodical articles, monographs, dissertations, reports and other materials on library instruction and information literacy published in 2020.
Findings
The paper provides a brief description of all 440 sources and highlights sources that contain unique or significant scholarly contributions.
Originality/value
The information may be used by librarians, researchers and anyone interested in a quick and comprehensive reference to literature on library instruction and information literacy.
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Steven J Karau and Janice R Kelly
Despite the potentially vital implications of time pressure for group performance in general and team effectiveness in particular, research has traditionally neglected the study…
Abstract
Despite the potentially vital implications of time pressure for group performance in general and team effectiveness in particular, research has traditionally neglected the study of time limits and group effectiveness. We examine the small, but growing, body of research addressing the effect of time pressure on group performance and introduce our Attentional Focus Model of group effectiveness (Karau & Kelly, 1992). We examine recent research on the utility of the model and identify selected implications of the model for how time pressure may interact with other factors such as task type, group structure, and personality to influence team performance. Finally, we discuss methodological issues of studying attention, interaction processes, and team performance.