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This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

This study examined changes in work precarity (i.e., job insecurity and income insecurity) and involuntary job loss following the start of the Great Recession in 2007 among people with and without disabilities. Using five waves of nationally representative data from the Americans' Changing Lives (ACL) panel study, the findings demonstrated that people with disabilities who had early experiences of income insecurity were more likely to experience later income insecurity than people without disabilities. Those who had a functional disability and experienced job insecurity and income insecurity at W1, in 1986, were also significantly more likely to experience involuntary job loss following the start of the Great Recession. These findings highlight the disproportionate impact of early work precarity for people with disabilities and are discussed as an application of the life-course concept of cumulative disadvantage.

This paper aims to present an analytical insight into the effect known as lift offset. This effect may be of advantage in terms of power consumption when configurations that consists of two main rotors (coaxial, tandem, etc.) are operated at high speed forward flight. Fundamentally, each of the main rotors is producing a roll moment in opposite direction that is overall canceled to allow trim. The first-order phenomena of lift offset are therefore related to the load distribution over each rotor and may be analyzed independently of the interaction between the rotors.

Using simple analytical model, this paper analytically and explicitly evaluates the lift offset effect. It also demonstrates in a closed analytical form the various phenomena involved, including the optimal values obtained.

The paper shows that the main effect of lift offset is its influence on the lift coefficient distribution over the disk. It is also demonstrated that lift offset substantially reduces both the average and the azimuthal variation of the lift coefficient.

Comparison with numerical predictions shows adequate correlation. Overall, the insight provided may be use as a guideline for advance design of rotorcraft configurations of coaxial/tandem rotor systems.

The purpose of this paper is to reveal the lived experiences of dyslexics in engaging with all kinds of alphanumeric authentication mechanisms.

A significant proportion of the world’s population experiences some degree of dyslexia, which can lead to spelling, processing, sequencing and retention difficulties. Passwords, being essentially sequences of alphanumeric characters, make it likely that dyslexics will struggle with these, even more so than the rest of the population. Here, this study explores the difficulties people with dyslexia face, their general experiences with passwords, the coping strategies they use and the advice they can provide to developers and others who struggle with passwords. This paper collects empirical data through semi-structured interviews with 13 participants. Thematic analysis was used to provide an in-depth view of each participant’s experience.

The main contribution of this paper is to provide evidence related to the inaccessibility dimensions of passwords as an authentication mechanism, especially for dyslexics and to recommend a solution direction.

There is a possible volunteer bias, as this study is dealing with self-reported data including historical and reflective elements and this paper is seeking information only from those with self-declared or diagnosed dyslexia. Furthermore, many expressed interest or curiosity in the relationship between dyslexia and password difficulties, for some a motivation for their participation. Finally, given that the participants told us that dyslexics might hide, it is possible that the experiences of those who do hide are different from those who chose to speak to us and thus were not hiding.

A few authors have written about the difficulties dyslexics face when it comes to passwords, but no one has asked dyslexics to tell them about their experiences. This paper fills that gap.

The dramatic expansion in the use and capability of electronic devices in recent years has been facilitated by the substantial development of production techniques. Modern electronic circuits as used in the computer, defence, aerospace, vehicle and domestic appliance industries contain a great many joints and these have to be made reliably and economically without degrading sensitive circuit components. This article describes the major microjoining developments currently of interest to the microelectronics industry, with emphasis on the work conducted by the microjoining section of The Welding Institute, much of which has been directly sponsored by the UK Ministry of Defence (DCVD).

This chapter reflects on how ethics was managed in Basque educational ethnographic research. Specifically, it addresses researcher positionality when relating to research collaborators in an attempt to manage inclusive ethics in situ. Nowadays, most research is evaluated by an ethical review board that ensures adequate research practice. However, unexpected fieldwork events need to be managed in the field, and this chapter addresses the impact of these events on the relationship between researchers and collaborators. Influenced by a post-qualitative stance we posit that research collaborators should be included in the research process. It reflects on the data collected during an ongoing ethnographic study with higher education students. The method used includes several interview meetings between researchers and collaborators, multimodal representations of collaborators' learning, and participants' self-observations. In the interviews, participants' discourses, representations, and self-observations were collaboratively analysed. The ethnographic data from these meetings show how researchers use a collaborative approach to practise ethics. Through such meetings, the knowledge derived from the ethnographic data is co-constructed in a research relationship where participants engage in dialogue and negotiation about the discourse created around them. Based on this relationship, we propose the concept of inclusive ethics as a process requiring an honest, inclusive, and collaborative relationship with the research subject.

The purpose of this paper is to provide an axisymmetric model of tube hydroforming using a Fourier Series based finite element method.

Fourier series interpolation function, which considerably reduces the size of the global stiffness matrix and the number of variables, is employed to approximate displacements. The material of the tube is assumed to be elastic‐plastic and to satisfy the plasticity model that takes into account the rate independent work hardening and normal anisotropy. Numerical solution obtained from an updated Lagrangian formulation of the general shell theory is employed. The axial displacement stroke (a.k.a. axial feed) during tube hydroforming is incorporated using Lagrange multipliers. Contact constraints and boundary friction condition are introduced into the formulation based on the penalty function, which imposes the constraints directly into the tangent stiffness matrix. A forming limit curve based on shear instability and experimental measurements are used as fracture criteria.

The results obtained from this new formulation are compared against the nonlinear finite element code ABAQUS and experimental measurements for isotropic and transversely anisotropic tube materials. The hoop and axial strains predicted with AXHD code compared excellently with those from ABAQUS FEM code using plane stress axisymmetric (SAX1) and four‐node shell (S4R) elements. However, in the case of aluminum, the numerically predicted maximum hoop strain underestimated the actual hoop strain measured from the tube bulging experiment.

The axisymmetric hydroforming program (AXHD) developed in this work is very efficient in simulating the free‐forming stage of the tube hydroforming process under simultaneous action of internal pressurization and displacement stroke.

Although Fourier Series based finite element method has been used in metal forming, the extended application presented in this paper is novel in the finite element analysis of tube hydroforming.

In the United States, first generation robots are doing die casting, forging, upsetting, plastic molding, machine loading, spot welding, assembly, glass tube handling, paint spraying, conveyor loading, handling explosives and radio active materials, and many other jobs which as can be seen, cover many fields and fabricating industries. Figs 7–14 illustrate first generation robots in action on some of the jobs just mentioned.

In 1970 only two manufacturers existed in the United States, namely the American Machine and Foundry (AMF) Versatran and the Unimation, Inc. Unimate. These robots, still in the forefront today, were just emerging and gaining acceptance in 1970, with approximately 200 industrial robots at work in the U.S., and an amassed 600,000 hours on the job, a negligible amount considering that the total U.S.blue collar work force puts in 200 million hours each day. However more than seventeen types of robots are now available in the U.S. at least twelve of which are manufactured in this country. They range from minirobots with payloads of only a few ounces and reaches of less than a foot to the larger universal robots which can handle payloads of up to 150 lbs., reach 3 ½ ft., and move at speeds up to 3 ft./sec. Recent additions to the U.S. arsenal are the Burch Control robot with a payload capacity of 6000 lbs. Industrial robots are easily reprogrammable, operatorless handling devices that can perform simple, repetitive jobs that require few alternative actions and minimum communications with the work environment. They are well suited to handling parts that are red hot or feezing cold, and they can function in corrosive, noxious or extremely dusty atmospheres that would be injurious to human beings. Passage in the United States of the Occupational Safety and Health Act of 1970 has provided strong impetus for the use of industrial robots. As discussed in a recent article in Assembly Engineering Magazine (Ref.1), the Act currently states that a human being cannot place his hands within punch press dies to load or remove parts, and it is imminent that OSHA standards will be extended to cover other fabricating and assembly machines, such as staking presses, spot welding machines, riveting machines, holding and clamping equipment, electron component Inserting equipment, and automatic screwdriving machines. In many cases the cost and time to retool an existing operation to conform to the standards will be prohibitive compared to the cost and time required to purchase and program an industrial robot to perform the potentially dangerous operations.