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Self‐inductance calculations are presented for coils of modular construction. Individual modules have a fixed winding density, so that a complete multi‐module coil will be characterized by larger inter‐turn spacing at its extremities to provide suitable insulation strength under impulse voltage conditions. Gives inductance computations using finite‐element analysis, so that empirical correction factors to take account of end‐effects and inter‐turn spacing are unnecessary. Comparison where possible with established empirical methods shows consistency. Gives an example of oscillatory high‐voltage tests.

SINCE man first aspired to fly the desire to take‐off and land vertically and to hover in flight has always presented a challenge to the engineer. To date only the rotary wing aircraft has achieved these aims in service but their shortcomings in terms of speed, range and economy have encouraged engineers to search for more elegant ways of achieving vertical flight.

Crack tip stresses are used to relate the ability of structures to perform under the influence of cracks and defects. One of the methods to determine three-dimensional crack tip stresses is through the J-T_z method. The J-T_z method has been used extensively to characterize the stresses of cracked geometries that demonstrate positive T-stress but limited in characterizing negative T-stresses. The purpose of this paper is to apply the J-T_z method to characterize a three-dimensional crack tip stress field in a changing crack length from positive to negative T-stress geometries.

Elastic-plastic crack border fields of deep and shallow cracks in tension and bending loads were investigated through a series of three-dimensional finite element (FE) and analytical J-T_z solutions for a range of crack lengths ranging from 0.1⩽a/W⩽0.5 for two thickness extremes of B/(W − a)=1 and 0.05.

Both the FE and the J-T_z approaches showed that the combined in-plane and the out-of-plane constraint loss were differently affected by the T-stress and the out-of-plane size effects when the crack length changed from deep to shallow cracks. The conditions of the J-T_z dominance on the three-dimensional crack front tip were shown to be limited to positive T-stress geometries, and the J-T_z-Q^2D approach can extend the crack border dominance of the three-dimensional deep and shallow bend models along the crack front tip until perturbed by an elastic-plastic corner field.

The paper reports the limitation of the J-T_z approach, which is used to calculate the state of three-dimensional crack tip stresses in power law hardening materials. The results from this paper suggest that the characterization of the three-dimensional crack tip stress in power law hardening materials is still an open issue and requires other suitable solutions to solve the problem.

This paper demonstrates a thorough analysis of a three-dimensional elastic-plastic crack tip fields for geometries that are initially either fully constrained (positive T-stress) or unconstrained (negative T-stress) crack tip fields but, subsequently, the T-stress sign changes due to crack length reduction and specimen thickness increase. The J-T_z stress-based method has been tested and its dominance over the crack tip field is shown to be affected by the combined in-plane and the out-of-plane constraints and the corner field effects.

THE “escalator” method of solving frequency equations, developed by Morris and Head (Ref. 1), and the natural extension of a Lemma by Professor Temple, together enable simple proofs to be given of two important fundamental theorems:

Research has long focused on the notion of access and the trajectory towards a healthcare encounter but has neglected what happens to patients after these initial encounters. This paper focuses attention on what happens after an initial healthcare encounter leading to a more nuanced understanding of how patients from a diverse range of backgrounds make sense of medical advice, how they mix this knowledge with other forms of information and how they make decisions about what to do next.

Drawing on 160 in-depth interviews across four European countries the paper problematizes the notion of access; expands the definition of “decision partners”; and reframes the medical encounter as a journey, where one encounter leads to and informs the next.

This approach reveals the significant unseen, unrecognised and unacknowledged work that patients undertake to solve their health concerns.

De-centring the professional from the healthcare encounter allows us to understand why patients take particular pathways to care and how resources might be more appropriately leveraged to support both patients and professionals along this journey.

The current outbreak of COVID-19 is an unprecedented event in air transportation. In this study, we investigate the impact of COVID-19 on global air transportation through the lens of complex networks different at different scales, ranging from worldwide airport networks where airports are nodes and links between airports exist when direct flights exist, to international country networks where countries are contracted as nodes, and to domestic airport networks for representative countries/regions. We focus on the spatial-temporal evolutionary dynamics of COVID-19 in air transportation networks, discovering hidden patterns on flight frequency reduction. Our study provides a comprehensive empirical analysis on the impact of the COVID-19 pandemic on aviation from a complex system perspective.

This paper explores how task characteristics in terms of trigger type and task topic influence individual participation in community-based free/libre open source software (FLOSS) development by considering participation in individual tasks rather than entire projects.

A quantitative study was designed using choose tasks that were carried out via the email discourse on the developers' email fora in five FLOSS projects. Choice process episodes were selected as the unit of analysis and were coded for the task trigger and topic. The impact of these factors on participation (i.e. the numbers of participants and messages) was assessed by regression.

The results reveal differences in participation related to different task triggers and task topics. Further, the results suggest the mediating role of the number of participants in the relationships between task characteristics and the number of messages. The authors also speculate that project type serves as a boundary condition restricting the impacts of task characteristics on the number of participants and propose this relationship for future research.

Empirical support was provided to the important effects of different task characteristics on individual participation behaviors in FLOSS development tasks.

The findings can help FLOSS participants understand participation patterns in different tasks and choose the types of tasks to attend to.

This research explores the impact of task characteristics on participation in FLOSS development at the task level, while prior research on participation in FLOSS development has focused mainly on factors at the individual and/or project levels.

The purpose of this paper is to engage in a thought experiment, exploring the use of Wikipedia or similar content‐malleable systems for the review and dissemination of academic knowledge.

By looking at other sources, the paper considers the current state of the academic peer‐review process, discusses Wikipedia and reflects on dynamic content creation and management applications currently in use in academia.

The traditional peer review process must be updated to match the rapid creation and diffusion of knowledge that characterises the 21st century. The Wikipedia concept is a potential model for more rapid and reliable dissemination of scholarly knowledge. The implications of such a concept would have a dramatic effect on the academic community.

This paper promotes a radical idea for changing the methods by which academic knowledge is both constructed and disseminated.

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.

The age‐old question of “what's in a name?” is analysed from a marketing standpoint. The author studies the manifold effects of different names upon us, in a general context, and isolates two opposing principle's for evaluating brand nomenclature: the Juliet principle, in which a name is justified by its traditional associations; and the Joyce principle, where names depend on their phonetic symbolism to communicate an idea. Certain groups of letters have been shown, by experiment, to possess qualities of “darkness” or “lightness”, “largeness” or “smallness”, etc., to a concensus of people. A word can also have a symbolic function arising from the associations it produces in the minds of consumers. The author proceeds from these suggestions to evolve guidelines for those engaged in the creation of new brand names. He discusses the evaluation of not only “traditional” names, but also apparently meaningless names like “Omo” or “Kleenex”, and shows how certain names work, or might be expected to work, in the market situation. The name is the one unchangeable part of the marketing mix. This psycholinguistic approach helps to put the question of the “naming of brands” into perspective, giving criteria for a “good” name, and elucidating the stages of arriving at it. Finally, the author points out that wholeness of approach is necessary —the felicity of the name chosen will be conditioned by the depth of involvement of relevant personnel concerned with the new product.