A comprehensive method to identify the kinetics of static recrystallization using the hot torsion test results with an inverse solution

Many difficulties exist in directly following the static recrystallization of metals, particularly during hotworking. Indirect measurement of static recrystallization has been extensively performed in the literature where, for example, the recrystallization behavior of austenite in steels has commonly been measured indirectly using the fractional softening method. This method relies on the yield stress changes during recrystallization which are physically simulated by hot torsion or compression tests. However, the inherent heterogeneity of deformation during a mechanical test leads to a non-uniform static recrystallization distribution in the test sample. This, in turn, poses a serious question concerning the reliability of the measurement since the stress calculation techniques during recrystallization are not adequately developed in the existing literature. This paper develops a computer-based method to account for heterogeneous deformation during fractional softening measurements based on the hot torsion test data. The importance of the fractional softening gradient in determining the kinetics is emphasized and deficiencies in our understanding of the basic mechanisms are highlighted. A computer-based method is introduced to generate the experimental and computational components in a cost function. The cost function is then utilized by an inverse solution to calibrate the design parameters in a static recrystallization model.

Theories into practice: understanding and rethinking our work with young children and the EYLF

This book introduces and explores each of the five major groups of theories described in the Early Years Learning Framework that inform practice in the early childhood field. In doing so, it addresses the need of the early childhood educators to better understand how their practice is underpinned by theories of learning and development.Educators draw from a range of perspectives, but it can sometimes be difficult to understand the link between theorists, theories and perspectives and their own practice. This book makes these links clear and easy to understand so educators can talk with more authority to colleagues, families and communities about their work, and reflect constructively on their practice.Each chapter deals with a different group of theories, briefly outlining the major thrust of each group and what it might look like in practice. Some of the major theorists are then focused on in turn. Discussion starter topics follow each theorist to promote discussion on the main topics and threads of the theorist’s thinking. This is followed by questions for reflection that relate more to thinking about the main concepts in relation to practice.

Performing desistance: how might theories of desistance from crime help us understand the possibilities of prison theatre?

Despite the ubiquity of theatre projects in prisons there has been little (published) discussion of the application of theatre to the theories of criminology or rehabilitation of offenders, and scant examination of the potential for criminological theories to inform theatre practice in criminal justice settings. This article seeks to address this deficit and argues that positioning prison theatre within the discipline of positive criminology, specifically contemporary theories of desistance from crime, provides a theoretical framework for understanding the contribution that prison theatre might be making in the correctional setting. Through a review of related literature, the article explores how prison theatre may be motivating offenders toward the construction of a more adaptive narrative identity and toward the acquisition of capabilities that might usefully assist them in the process of desisting from crime.

Applicability of financial theories of capital structure to the Chinese cultural context: a study of privately owned SMEs

Using a new dataset of 1539 Chinese small and medium-sized enterprises this article investigates the firm-level determinants of capital structure and tests them against the predictions of financial theory. Firm size and profitability are both found to be related to leverage as posited by pecking-order theory. In contrast little support is found for the predicted relationship between asset structure and leverage. These findings are discussed in relationship to their Chinese cultural context. The managerial and policy implications of the research are then explored.

Current and future friends of the earth: assessing cross-national theories of environmental attitudes

Empirical studies of public opinion on environmental protection have typically been grounded in Inglehart’s post-materialism thesis, proposing that societal affluence encourages materially-sated publics to look beyond their interests and value the environment. These studies are generally conducted within, or at best across, Western, democratic, industrialized countries. Absence of truly cross-cultural research means the theory’s limitations have gone undetected. This article draws on an exceptionally broad dataset—pooling cross-sectional survey data from 80 countries, each sampled at up to three different points over 15 years—to investigate environmental attitudes. We find that post-materialism provides little account of pro-environment attitudes across diverse cultures, and a far from adequate explanation even in the affluent West. We suggest that unique domestic interests, more than broad value systems, are driving emerging global trends in environmental attitudes. The environment’s future champions may be the far from ‘post-material’ citizens of those developing nations most at risk of real material harm from climate change and environmental degradation.

Strain gradient plasticity modelling of high-pressure torsion

Gradient plasticity modelling combining a micro-structure-related constitutive description of the local material behaviour with a particular gradient plasticity frame is presented. The constitutive formulation is based on a phase mixture model in which the dislocation cell walls and the cell interiors are considered as separate 'phases', the respective dislocation densities entering as internal variables. Two distinct physical mechanisms, which give rise to gradient plasticity, are considered. The first one is associated with the occurrence of geometrically necessary dislocations leading to first-order strain gradients; the second one is associated with the reaction stresses due to plastic strain incompatibilities between neighbouring grains, which lead to second-order strain gradients. These two separate variants of gradient plasticity were applied to the case of high-pressure torsion: a process known to result in a fairly uniform, ultrafine grained structure of metals. It is shown that the two complementary variants of gradient plasticity can both account for the experimental results, thus resolving a controversial issue of the occurrence of a uniform micro-structure as a result of an inherently non-uniform process. © 2007 Elsevier Ltd. All rights reserved.

Enhanced ductility and reduced asymmetry of Mg-2Al-1Zn alloy plate processed by torsion and annealing

The ductility and plastic asymmetry of an as-annealed magnesium alloy plate were studied in compression through combined process of torsion and subsequent annealing by optical microscope and EBSD. The yield strength (YS) and ultimate compression strength (UCS) as well as the compression ductility (CD) were simultaneously raised by prior torsion at room temperature. The CD was further enhanced by subsequent annealing. Also, the torqued sample followed by annealing experienced a rising CD with the increase in prior strain, leading to the maximum true strain of 0.279, which is twice that of the as-annealed original one. The sample showed a largely reduced tension-compression yield asymmetry by subjecting to pre-torsion alone or combined with a subsequent annealing. The enhanced ductility and reduced asymmetry are attributed to the development of a gradient microstructure with refined grains, and also randomization of the weakened texture due to torsion and subsequent annealing.

A succession of theories : purging redundancy from disturbance theory

The topics of succession and post-disturbance ecosystem recovery have a long and convoluted history. There is extensive redundancy within this body of theory, which has resulted in confusion, and the links among theories have not been adequately drawn. This review aims to distil the unique ideas from the array of theory related to ecosystem change in response to disturbance. This will help to reduce redundancy, and improve communication and understanding between researchers. We first outline the broad range of concepts that have developed over the past century to describe community change in response to disturbance. The body of work spans overlapping succession concepts presented by Clements in 1916, Egler in 1954, and Connell and Slatyer in 1977. Other theories describing community change include state and transition models, biological legacy theory, and the application of functional traits to predict responses to disturbance. Second, we identify areas of overlap of these theories, in addition to highlighting the conceptual and taxonomic limitations of each. In aligning each of these theories with one another, the limited scope and relative inflexibility of some theories becomes apparent, and redundancy becomes explicit. We identify a set of unique concepts to describe the range of mechanisms driving ecosystem responses to disturbance. We present a schematic model of our proposed synthesis which brings together the range of unique mechanisms that were identified in our review. The model describes five main mechanisms of transition away from a post-disturbance community: (i) pulse events with rapid state shifts; (ii) stochastic community drift; (iii) facilitation; (iv) competition; and (v) the influence of the initial composition of a post-disturbance community. In addition, stabilising processes such as biological legacies, inhibition or continuing disturbance may prevent a transition between community types. Integrating these six mechanisms with the functional trait approach is likely to improve the predictive capacity of disturbance theory. Finally, we complement our discussion of theory with a case study which emphasises that many post-disturbance theories apply simultaneously to the same ecosystem. Using the well-studied mountain ash (Eucalyptus regnans) forests of south-eastern Australia, we illustrate phenomena that align with six of the theories described in our model of rationalised disturbance theory. We encourage further work to improve our schematic model, increase coverage of disturbance-related theory, and to show how the model may link to, or integrate with, other domains of ecological theory.

Radicalisation theories, policing practices, and “the future of terrorism?”

This article explores how theories of radicalisation have placed an emphasis on the development of an indicators-based approach to identify individuals who might engage in politically motivated violence. We trace how policing agencies have juxtaposed the search for indicators as a defence against criticisms of racial profiling. However, through an analysis of Canadian counter-terrorism training programmes, we demonstrate that the search for radicalisation indicators reaffirms pre-emptive and discriminatory security practices. We insist that despite efforts to theorise radicalisation outside of the practices of the “war on terror”, current trends risk rationalising prejudicial policing that affirms social exclusion and injustice.

Better the devil you know than a world you don't? Intolerance of uncertainty and worldview explanations for belief in conspiracy theories

Conspiracy Theory (CT) endorsers believe in an omnipresent, malevolent, and highly coordinated group that wields secret influence for personal gain, and credit this group with the responsibility for many noteworthy events. Two explanations for the emergence of CTs are that they result from social marginalisation and a lack of agency, or that they are due to a need-to-explain-the-unexplained. Furthermore, representativeness heuristics may form reasoning biases that make such beliefs more likely. Two related studies (N = 107; N = 120) examined the relationships between these social marginalisation, intolerance of uncertainty, heuristics and CT belief using a correlational design. Overall, intolerance of uncertainty did not link strongly to CT belief, but worldview variables did - particularly a sense of the world as (socially) threatening, non-random, and with no fixed morality. The use of both representative heuristics that were examined was heightened in those participants more likely to endorse CTs. These factors seem to contribute to the likelihood of whether the individual will endorse CTs generally, relating similarly to common CTs, CTs generally historically accepted as "true", and to the endorsement of fictional CTs that the individual would find novel. Implications are discussed.

The applicability of self-regulation theories in sport: Goal adjustment capacities, stress appraisals, coping, and well-being among athletes

We examined a model, informed by self-regulation theories from the health psychology literature, which included goal adjustment capacities, appraisals of challenge and threat, coping, and well-being. Two-hundred and twelve athletes from the United Kingdom (n 147)= or Australia (n = 65), who played team (n = 135) or individual sports (n = 77), and competed at international (n = 7), national (n = 11), county (n = 67), club (n = 84), or beginner (n = 43) levels participated in this study. Participants completed measures of goal adjustment capacities and stress appraisals two days before competing. Athletes also completed coping and well-being questionnaires within three hours of their competition ending.The way an athlete responded to an unattainable goal was associated with his or her well-being in the period leading up to and including the competition. Goal reengagement positively predicted well-being, whereas goal disengagement negatively predicted well-being. Further, goal reengagement was positively associated with challenge appraisals, which in turn was linked to task-oriented coping, and task-oriented coping positively associated with well-being.When highly-valued goals become unattainable, consultants and coaches could encourage athletes to generate alternative approaches to achieve the same goal or help them develop a completely new goal in order to promote well-being among athletes.

Big data concepts, theories, and applications

Big data is one of the hottest research topics in science and technology communities, and it possesses a great potential in every sector for our society, such as climate, economy, health, social science, and so on. Big data is currently treated as data sets with sizes beyond the ability of commonly used software tools to capture, curate, and manage. We have tasted the power of big data in various applications, such as finance, business, health, and so on. However, big data is still in her infancy stage, which is evidenced by its vague definition, limited application, unsolved security and privacy barriers for pervasive implementation, and so forth. It is certain that we will face many unprecedented problems and challenges along the way of this unfolding revolutionary chapter of human history.