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Contact problems are among the most difficult ones in mechanics. Due to its practical importance, the problem has been receiving extensive research work over the years. The finite element method has been widely used to solve contact problems with various grades of complexity. Great progress has been made on both theoretical studies and engineering applications. This paper reviews some of the main developments in contact theories and finite element solution techniques for static contact problems. Classical and variational formulations of the problem are first given and then finite element solution techniques are reviewed. Available constraint methods, friction laws and contact searching algorithms are also briefly described. At the end of the paper, a bibliography is included, listing about seven hundred papers which are related to static contact problems and have been published in various journals and conference proceedings from 1976.

Recently Foster and Ryan developed a new method for the vehicle scheduling problem (VSP). This article applies their method to a practical VSP involving the delivery of pressurised fluids, and demonstrates its effectiveness.

In the last two decades Ontario’s universities have been experiencing major financial and administrative re-structuring resulting in decision-making challenges, specifically in relation to a decreasing focus on ethical leadership and good governance. Ethical decision-making in Ontario universities is multifaceted because of the variety and complexity of demands placed on the senior administrative units and the bicameral structure of many universities, which is composed of a Board of Governors and a Senate. The authors propose approaches to improve ethical leadership and governance that focus on servant leadership, reflection, and stewardship within the bicameral process to support greater trust amongst elected and appointed senior decision-makers in Ontario’s university sector.

The purpose of this paper is to compute the stress intensity factors (SIFs) of single edge interface crack for arbitrary material combinations and various relative crack lengths, and compare with those for the bonded plates subjected to tensile loading conditions. It aims to discuss the results of the shallow edge interface crack on the basis of the singular stress near the free‐edge corner without the crack.

In this study, the SIFs of interface crack in dissimilar bonded plates subjected to bending loading conditions are analyzed by the finite element method and a post‐processing technique. The use of post‐processing technique of extrapolation reduces the computational cost and improves the accuracy of the obtained result.

The empirical expressions are proposed for evaluating the SIFs of arbitrary material combinations.

Empirical functions can be used to obtain the SIFs for arbitrary material combinations for the bending loading conditions easily. It is very convenient for engineering application.

The paper's aim is to predict numerically the contact temperatures between two rough sliding bodies and to compare with the experimental results.

An elastic contact algorithm is used to analyze the normal contact between two nominally smooth surfaces. The algorithm evaluates real contact area using digitized roughness data and the corresponding contact pressure distribution. Using finite element method a steady state 3D temperature distribution at the interface between the sliding bodies is obtained. Using infrared (IR) imaging technique, experiments were carried out to measure the contact temperature distribution between rough rubbing bodies with a systematic variation of surface roughness and operating variables.

Contact temperature distributions over a wide range of normal load, sliding velocity and surface roughness have been obtained. It was seen that the maximum contact temperature expectedly increases with surface roughness (S_a values), normal load and sliding velocity. The results also indicate that the “hot spots” are located exactly at the positions where the contact pressures are extremely high. Temperatures can be seen to fall drastically at areas where no asperity contacts were established. The temperature contours at different depths were also plotted and it was observed that the temperatures fall away from the actual contact zone and relatively high temperatures persist at the “hot spot” zones much below the contact surface. Finally it is encouraging to find a good correlation between the numerical and experimental results and this indicates the strength of the present analysis.

Experimental accuracy can be improved by using a thermal imaging camera that measures emissivity in situ and uses it to find the contact temperature. The spatial resolution and the response time of the camera also need to be improved. This can improve the correlation between numerical and experimental results.

One of the major factors attributed to the failure of sliding components is the frictional heating and the resulting flash temperatures at the sliding interface. However, it is not easy to measure such temperatures owing to the inherent difficulties in accessing the contact zone. Besides, thermal imaging techniques can be applied only with such tribo‐pairs where at least one of the contacting materials is transparent to IR radiation. In practice, such cases are a rarity. However, the good correlation observed between the numerical and experimental results in this work would give the practicing engineer a confidence to apply the numerical model directly and calculate contact temperatures for any tribo‐material pairs that are generally seen around.

A good correlation between the numerical and experimental results gives credence to the fact that the numerical model can be used to predict contact temperatures between any sliding tribo‐pairs.

Gives a bibliographical review of the error estimates and adaptive finite element methods from the theoretical as well as the application point of view. The bibliography at the end contains 2,177 references to papers, conference proceedings and theses/dissertations dealing with the subjects that were published in 1990‐2000.

The purpose of this paper is to present the characteristics of elastic-plastic deformation and stress fields at the intersection of a crack front and the free surface of a three-dimensional body, referred to as corner fields.

The structures of elastic-plastic corner deformation field were assessed experimentally by looking at the corner border displacement and strain fields on the surface of a compact tension (CT) specimen using digital image correlation method. For assessment and verification purposes, the results were compared with the fields predicted through finite element analysis. The latter method was used further to assess the corner stress field.

The characteristics of displacement, strain and stress fields in the vicinity of a corner vertex in a finite geometry CT specimen in a strain hardening condition are independent of load and geometry. One of the distinctive features that becomes evident in this study is that the stress state at the corner vertex at θ=0° is a simple uniaxial tension.

This paper provides some insights on the structure of elastic-plastic corner fields that could optimistically be served as a fundamental framework towards the development of analytical solutions for elastic-plastic corner fields.

Purpose: We critically examine the idea of neurodiversity, or the uniqueness of all brains, as the foundation for the neurodiversity movement, which began as an autism rights movement. We explore the neurodiversity movement's potential to support cross-disability alliances that can transform cultures.

Methods/Approach: A neurodiverse team reviewed literature about the history of the neurodiversity movement and associated participatory research methodologies and drew from our experiences guiding programs led, to varying degrees, by neurodivergent people. We highlight two programs for autistic university students, one started by and for autistics and one developed in collaboration with autistic and nonautistic students. These programs are contrasted with a national self-help group started by and for stutterers that is inclusive of “neurotypicals.”

Findings: Neurodiversity-aligned practices have emerged in diverse communities. Similar benefits and challenges of alliance building within versus across neurotypes were apparent in communities that had not been in close contact. Neurodiversity provides a framework that people with diverse conditions can use to identify and work together to challenge shared forms of oppression. However, people interpret the neurodiversity movement in diverse ways. By honing in on core aspects of the neurodiversity paradigm, we can foster alliances across diverse perspectives.

Implications/ Values: Becoming aware of power imbalances and working to rectify them is essential for building effective alliances across neurotypes. Sufficient space and time are needed to create healthy alliances. Participatory approaches, and approaches solely led by neurodivergent people, can begin to address concerns about power and representation within the neurodiversity movement while shifting public understanding.

It has often been said that a great part of the strength of Aslib lies in the fact that it brings together those whose experience has been gained in many widely differing fields but who have a common interest in the means by which information may be collected and disseminated to the greatest advantage. Lists of its members have, therefore, a more than ordinary value since they present, in miniature, a cross‐section of institutions and individuals who share this special interest.