Structuring in liquid alkanes between solid surfaces : force measurements and mean-field theory

Measurements have been made of the solvation forces between mica surfaces in the even-numbered n-alkanes from hexane to hexadecane. In all cases the force law is qualitatively very similar, characterized by a decaying oscillatory function of distance, as occurs for simple isotropic liquids. The spacing between successive minima in the force does not increase with carbon number, and is comparable to the width of a linear alkane molecule rather than its length or any average diameter. This suggests that the alkanes have some tendency towards a parallel orientation near the mica surfaces. The measurements give no indication of any strong repulsive component expected from mean-field theories of higher alkanes or polymers. The results of one such theory are presented, and the reasons for its failure to match the experimental data are discussed.

Stability theory and numerical analysis of non-autonomous dynamical systems

The development and use of cocycles for analysis of non-autonomous behaviour is a technique that has been known for several years. Initially developed as an extension to semi-group theory for studying rion-autonornous behaviour, it was extensively used in analysing random dynamical systems [2, 9, 10, 12]. Many of the results regarding asymptotic behaviour developed for random dynamical systems, including the concept of cocycle attractors were successfully transferred and reinterpreted for deterministic non-autonomous systems primarily by P. Kloeden and B. Schmalfuss [20, 21, 28, 29]. The theory concerning cocycle attractors was later developed in various contexts specific to particular classes of dynamical systems [6, 7, 13], although a comprehensive understanding of cocycle attractors (redefined as pullback attractors within this thesis) and their role in the stability of non-autonomous dynamical systems was still at this stage incomplete. It was this purpose that motivated Chapters 1-3 to define and formalise the concept of stability within non-autonomous dynamical systems. The approach taken incorporates the elements of classical asymptotic theory, and refines the notion of pullback attraction with further development towards a study of pull-back stability arid pullback asymptotic stability. In a comprehensive manner, it clearly establishes both pullback and forward (classical) stability theory as fundamentally unique and essential components of non-autonomous stability. Many of the introductory theorems and examples highlight the key properties arid differences between pullback and forward stability. The theory also cohesively retains all the properties of classical asymptotic stability theory in an autonomous environment. These chapters are intended as a fundamental framework from which further research in the various fields of non-autonomous dynamical systems may be extended. A preliminary version of a Lyapunov-like theory that characterises pullback attraction is created as a tool for examining non-autonomous behaviour in Chapter 5. The nature of its usefulness however is at this stage restricted to the converse theorem of asymptotic stability. Chapter 7 introduces the theory of Loci Dynamics. A transformation is made to an alternative dynamical system where forward asymptotic (classical asymptotic) behaviour characterises pullback attraction to a particular point in the original dynamical system. This has the advantage in that certain conventional techniques for a forward analysis may be applied. The remainder of the thesis, Chapters 4, 6 and Section 7.3, investigates the effects of perturbations and discretisations on non-autonomous dynamical systems known to possess structures that exhibit some form of stability or attraction. Chapter 4 investigates autonomous systems with semi-group attractors, that have been non-autonomously perturbed, whilst Chapter 6 observes the effects of discretisation on non-autonomous dynamical systems that exhibit properties of forward asymptotic stability. Chapter 7 explores the same problem of discretisation, but for pullback asymptotically stable systems. The theory of Loci Dynamics is used to analyse the nature of the discretisation, but establishment of results directly analogous to those discovered in Chapter 6 is shown to be unachievable. Instead a case by case analysis is provided for specific classes of dynamical systems, for which the results generate a numerical approximation of the pullback attraction in the original continuous dynamical system. The nature of the results regarding discretisation provide a non-autonomous extension to the work initiated by A. Stuart and J. Humphries [34, 35] for the numerical approximation of semi-group attractors within autonomous systems. . Of particular importance is the effect on the system's asymptotic behaviour over non-finite intervals of discretisation.

The mediatization of the knowledge based economy : an Australian field based account

This paper presents an empirical account of mediatization from a Bourdieuian perspective, based on the development of a number of new concepts, such as cross-field effects and the rescaling of such effects as linked to processes of globalization. Built on an Australian empirical case relating to educational policy and the knowledge based economy, this paper argues that mediatization can be understood in relation to the cross-field effects of different fields of journalism on subsequent fields, which have their genesis in forms of practice that cross different social fields. Specifically, the case analysis details interactions between the field of print journalism and the field of policy over the course of an Australian science capability review, chaired by the then chief scientist, Dr Robin Batterham, which led to Australia adopting a national version of the knowledge economy. The empirical case also leads us to consider the impact of both global and national fields of journalism on fields of educational policy in relation to mediatization.

Sharpening the focus of force field analysis

The purpose is to explore the inherent complexity of Kurt Lewin's force field theory through applied analysis of organizational case examples and related methods. The methodology applies a range of tools from the consultancy research domain, including force field analysis of complex organizational scenarios, and applies bricolage and corroboration to emerging discoveries from semi-structured interviews, author experience, critical reflection and literature survey. Findings are that linear representation of internal and external forces in organizational applications of field theory does not fully explain the paradox of inverse vectors in the forces of change. The force field is not an impermeable thing; instead, it morphs. Examples of the inverse principle and its effects are detailed and extended in this analysis. The implications of the research are that force field analysis and related change processes promoted in organizational change literature run the risk of missing key complexities. The inclusion of the inverse principle can provide enhanced, holistic understanding of the prevailing forces for change. The augmentation of the early work of Kurt Lewin, and extension of previous analyses of his legacy in the Journal of Change Management and elsewhere, provide, in this article, change analysis insights that align well with current organizational environments.

A dynamic ratio-based model for signalling corporate collapse

The recognition of behavioural elements in finance has caused major shifts in the analytic framework pertaining to ratio-based modeling of corporate collapse. The modeling approach so far has been based on the classical rational theory in behavioural economics, which assumes that the financial ratios (i.e., the predictors of collapse) are static over time. The paper argues that, in the absence of rational economic theory, a static model is flawed, and that a suitable model instead is one that reflects the heuristic behavioural framework, which is what characterises behavioural attributes of company directors and in turn influences the accounting numbers used in calculating the financial ratios. This calls for a dynamic model: dynamic in the sense that it does not rely on a coherent assortment of financial ratios for signaling corporate collapse over multiple time periods. This paper provides empirical evidence, using a data set of Australian publicly listed companies, to demonstrate that a dynamic model consistently outperforms its static counterpart in signaling the event of collapse. On average, the overall predictive power of the dynamic model is 86.83% compared to an average overall predictive power of 69.35% for the static model.

The determination of the local conditions for void initiation in front of a crack tip for materials with second-phase particles

A procedure is proposed to determine, for second-phase particles near a crack tip, the maximum particle stresses at the moment of void initiation by either particle fracture or particle/matrix interface separation. A digital image analysis system is applied to perform a quantitative analysis of corresponding fracture surface regions from stereo image pairs taken in the scanning electron microscope. The fracture surface analysis is used to measure, for individual particles, the crack tip opening displacement at the moment of void initiation and the particle location with respect to the crack tip. From these data, the stress tensor at the moment of void initiation is calculated from the Hutchinson–Rice–Rosengren (HRR) field theory. The corresponding average local stresses within the particle are evaluated by a non-linear Mori–Tanaka-type approach. These stresses are compared to estimates according to the models by Argon et al. [A.S. Argon, J. Im, R. Safoglu, Metall. Trans. 6 (1975) 825] and Beremin [F.M. Beremin, Metall. Trans. 12 (1981) 723]. The procedure is demonstrated on an Al6061–10% Al2O3 metal matrix composite.

Bringing Bourdieu to policy sociology : codification, misrecognition and exchange value in the UK context

The task of social scientists is to find ways of investigating and understanding the social, political and economic world, in order to offer insights into everyday and public life in the past, present and future. Bourdieu’s tool kit offers a particular way of theorizing the rules, narratives and self-held truths of social phenomena and of educational policy as a specific object of analysis. In this article I develop a series of propositions about the ways in which field theory might be applied to explain the abrupt public policy shift effected by the Thatcher government and the adjustments made to it by the Blair government. I suggest that a Bourdieuian approach shows policy working as a means of codification, as a doxa of misrecognition and as currency exchange within and across fields. I conclude with some thoughts about the difficulties of explicating interactions between fields.

Compression and extrusion of metals using rotating dies

Experimental and theoretical investigations of compression and extrusion of metals with steadily or cyclically rotating dies were carried out. Reasonably simple models were produced by classical plasticity theory and analytical equations were developed to establish a theoretical basis for the associated phenomena. Analytical solutions agreed well with the experimental results.

Assessment of movement participation for children with developmental coordination disorders

The Caregiver Assessment of Movement Participation was developed to identify children of 5-10 years old for movement participation difficulties in home contexts. Its psychometric properties were investigated including its usefulness as a screening instrument using both classical test theory methods and Rasch analysis. Results confirmed its validity and reliability.

Colloidal interaction between a rigid solid and a fluid drop

We present results of a theoretical study of the effect of surface deformation on a macroscopic system composed of a solid surface interacting with a fluid drop through electrostatic double-layer forces. The analysis involves numerically solving a Laplace equation suitably modified to describe the shape of a liquid drop subjected to a repulsive double-layer force. The latter is evaluated in nonlinear mean-field theory. Some analytical results are also given. The results indicate that although deformation need not be significant on the macroscopic scale, its effect on the interaction is significant and modifies the picture usually presented in DLVO theory. The decay length of the exponential repulsion deviates marginally from the Debye length, dependent on the interfacial tension of the drop. More significantly, at separations where the double-layer force becomes comparable to the internal pressure of the drop, the net force between the two bodies, the local radius of curvature of the drop, and the amount of deformation grow abruptly. The results of this work are relevant to emulsion stability, micelle, vesicle, and cell interactions, and recent experiments on bubble-particle interaction.

Flexural vibration analysis of symmetric honeycomb panel with 4 sides simply supported

The free flexural vibration of symmetric honeycomb sandwich panel with 4 sides simply supported is analyzed by CPT (classical plate theory), FSDPT (first-order shear deformation plate theory) and TSDPT (third-order shear deformation plate theory). In the analysis the honeycomb core of cells is regarded equivalently as a layer of orthotropic material whose equivalent elastic parameters are determined by the modified Gibson's formula to deduce the equation of natural frequency of the sandwich panel. As shown by an example, the calculation of natural frequency of an aluminum honeycomb panel by use of TSDPT is higher accuracy than using either CPT or FSDPT.

Bourdieu and educational research: thinking tools, relational thinking, beyond epistemological innocence

The main aim of this chapter is to provide an introduction to the theoretical work of Pierre Bourdieu, and to outline different ways in which Bourdieu’s work is influential and has been engaged with in education research and to suggest implicitly the usefulness of this work for educational researchers. In order to do this, we draw on a range of Bourdieu’s own writing published singly or with colleagues, emphasising in particular his engagements with education. Part of our treatment also deals with his wider writing that has subsequently been influential for education researchers, and in particular Bourdieu’s anthropological writing and account of practice (Bourdieu 1977, 1990), his approach to social class and cultural issues, his account of the judgement of taste and distinctions (Bourdieu, 1984), and his later politically focused writing (Bourdieu, 1989/1996, 2003, 2004c, 2005a).

Mediatization and education: a sociological account

This chapter presents an account of the mediatization of education policy through a focus on the development and uptake of the knowledge economy discourse in national education policy and research settings. During the late 20th and early part of the 21st century, Australia, like other nation states around the globe, came to adopt the knowledge economy discourse as a kind of meta-policy that would help connect a variety of statistical indicators and provide direction for a number of policy areas, including education, science, and research funding. In Australia the adoption of a knowledge economy discourse was preceded by coverage from specialized sections of the quality print media, discussed broadly as a debate about the social contract that was afforded to fields charged with developing and producing national capacities for knowledge production. Such a debate mirrored similar claims by Michael Gibbons in the late 1990s, where he argued for a new social contract between science and society. Given the media coverage surrounding the uptake of the knowledge economy discourse and the promotion of the concept by the OECD, this chapter presents an account of the emergence of the knowledge economy discourse through a focus on the mediatization of the concept. The broad argument presented in this account is that what could be called “mediatization effects”, related to the promotion and adoption of policy concepts, are variable, and reach the broader public in inconsistent, time-bound, and sporadic patterns. In order to understand mediatization effects in respect of policy, the paper draws on a broad Bourdieuian informed conceptual framework to understand different kinds of fields, their logics of practice, and importantly here, cross-field effects. Specifically, the focus is on those cross-field effects related to the impact of practices within both national and global fields of journalism on national and global fields of education policy. While the case is an Australian one, the account explores general and more broadly applicable ways to understand links between the globalization and the mediatization of policy.

A new computerized adaptive test advancing the measurement of health-related quality of life (HRQoL) in children: the Kids-CAT

Purpose: Assessing health-related quality of life (HRQoL) via Computerized Adaptive Tests (CAT) provides greater measurement precision coupled with a lower test burden compared to conventional tests. Currently, there are no European pediatric HRQoL CATs available. This manuscript aims at describing the development of a HRQoL CAT for children and adolescents: the Kids-CAT, which was developed based on the established KIDSCREEN-27 HRQoL domain structure. Methods: The Kids-CAT was developed combining classical test theory and item response theory methods and using large archival data of European KIDSCREEN norm studies (n = 10,577–19,580). Methods were applied in line with the US PROMIS project. Item bank development included the investigation of unidimensionality, local independence, exploration of Differential Item Functioning (DIF), evaluation of Item Response Curves (IRCs), estimation and norming of item parameters as well as first CAT simulations. Results: The Kids-CAT was successfully built covering five item banks (with 26–46 items each) to measure physical well-being, psychological well-being, parent relations, social support and peers, and school well-being. The Kids-CAT item banks proved excellent psychometric properties: high content validity, unidimensionality, local independence, low DIF, and model conform IRCs. In CAT simulations, seven items were needed to achieve a measurement precision between.8 and.9 (reliability). It has a child-friendly design, is easy accessible online and gives immediate feedback reports of scores. Conclusions: The Kids-CAT has the potential to advance pediatric HRQoL measurement by making it less burdensome and enhancing the patient–doctor communication.

Erratum to: A new computerized adaptive test advancing the measurement of health-related quality of life (HRQoL) in children: the Kids-CAT

Abstract
Purpose
Assessing health-related quality of life (HRQoL) via Computerized Adaptive Tests (CAT) provides greater measurement precision coupled with a lower test burden compared to conventional tests. Currently, there are no European pediatric HRQoL CATs available. This manuscript aims at describing the development of a HRQoL CAT for children and adolescents: the Kids-CAT, which was developed based on the established KIDSCREEN-27 HRQoL domain structure.
Methods
The Kids-CAT was developed combining classical test theory and item response theory methods and using large archival data of European KIDSCREEN norm studies (n=10,577–19,580). Methods were applied in line with the US PROMIS project. Item bank development included the investigation of unidimensionality, local independence, exploration of Differential Item Functioning (DIF), evaluation of Item Response Curves (IRCs), estimation and norming of item parameters as well as first CAT simulations.
Results
The Kids-CAT was successfully built covering five item banks (with 26–46 items each) to measure physical well-being, psychological well-being, parent relations, social support and peers, and school well-being. The Kids-CAT item banks proved excellent psychometric properties: high content validity, unidimensionality, local independence, low DIF, and model conform IRCs. In CAT simulations, seven items were needed to achieve a measurement precision between .8 and .9 (reliability). It has a child-friendly design, is easy accessible online and gives immediate feedback reports of scores.
Conclusions
The Kids-CAT has the potential to advance pediatric HRQoL measurement by making it less burdensome and enhancing the patient–doctor communication.