The compounding of short fibre reinforced thermoplastic composites

This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University.It is generally accepted that the mechanical properties of short fibre reinforced thermoplastics do not correspond with the high mechanical properties of fibres used to reinforce them. A study is made into the methods of compounding reinforcing fibres into thermoplastics to produce short fibre reinforced thermoplastics of enhanced properties. The initial method chosen for investigation is the twin screw extrusion compounding process. Variables such as fibre feeding arrangement and extrusion screw design are found to be factors influencing the properties of carbon and glass reinforced nylon 6,6. Use is made of computer programs to predict properties, assess compound quality and estimate fibre-matrix bond strength. Investigations indicate that the presence of reinforcing fibres with enhanced lengths does not result in the predicted property increases. The reasons for this shortfall are believed to lie in unfavourable fibre orientation in injection mouldings and the reduced strain to break of these materials. Short Kevlar reinforced thermoplastics are compounded and their mechanical properties assessed. The reasons for the poor mechanical properties for these materials are identified as a poor bond strength between fibre and matrix, the formation of points of weakness within the fibres by the compounding and moulding processes and the coiled arrangement of fibres present in injection mouldings. A method suitable for the routine assessment of fibre-matrix bond strength is used to examine combinations of fibre and thermoplastic matrix. A comparison is made of the values derived from this method with values calculated from stress-strain curves of injection mouldings. This allows an understanding of the nature of the fibre-matrix bond yielded by compounding and injection moulding steps. A description is given of a novel method designed to overcome the limitations of conventional compounding routes to produce long fibre reinforced injection moulding feedstock. Further work is necessary before this method is a feasible production technique

Education as sustainable development : Mangaia, Cook Islands

Listed in 2016 Dean's List of Exceptional ThesesSustainable development (SD) and Education for Sustainable Development (ESD) became prominent in the 1990s. Problematically, these western centric constructs have sometimes been used to justify greater economic growth despite concern about the environment. Simultaneously, greater awareness of the pivotal role culture plays in development has demanded the rethinking of SD in terms of culturally responsive and contextually relevant ‘alternatives to’ development. Using the case of Mangaia in the Cook Islands the aim of this research was to draw out Mangaians own visions for SD and their consequent expectations for the type of ESD delivered to students in the classroom. Situating the research within a hopeful postdevelopment framework a culturally responsive, open ended, critical research methodology was used to gain an understanding of what constitutes a Mangaian SD worldview. Using participatory semi structured interviews underpinned by Mangaian uriuri manako (reflective problem solving) preliminary frameworks for Mangaian SD and ESD were co-constructed. This thesis highlights that to Mangaian people SD is complex and multi modal consisting of an indigenous development centred on oraanga Mangaia and alternative modernities, embedded in culture, operating at the margins of the global economy. This Mangaian view of SD, interacting with externally driven development, is continually reinvented by the Mangaian people using both indigenous and western knowledge, in response to issues of sustainability. The study argues that current western centric ‘Education about’ and ‘Education for’ SD programmes do not reflect the cultural and contextual reality of SD in the Global South. Instead, Education as Sustainable Development (EasSD) is presented as a novel concept, which embraces learning taking place within culture and is able to respond to the context and dynamism of hopeful post-development settings: it is argued that this approach would provide students with the knowledge to be able to fashion community-based sustainable futures. An EasSD approach would expose students to a broader range of livelihoods options and have the ability to strengthen a student’s language, culture and identity while potentially improving their academic outcomes. A strength based implementation that draws on the support of all development and education stakeholders offers the best chance of actualising EasSD and so empowering students with the ability to participate in, and lead, their own communities’ SD

Towards a human resources management approach in supply chain management

Supply chain management (SCM) has grown as a discipline since the field attracted attention in the 1980s. However, it is observed that effective implementation of SCM is limited because the current focus is too task-based and information-centric. The concept is often conflated, in practice, with subcontractor management, where numerical flexibility is pertinent. At the same time, consideration of human resources management (HRM) in SCM has been limited. Strategic fit within supply chains tends to emphasise taskbased numerical flexibility, rather than genuine consideration and development of human resources. On the other hand, HRM has, until recently, rarely taken into account interorganisational characteristics that typify the construction industry. Therefore, this research intends to plug the gap by examining the use of human resources in construction supply chains, with a view of developing good practice for HRM in construction SCM. To achieve this, a two-phase research methodology comprising a scoping phase and case study phase will be ensued

Zvi Griliches on Diffusion, Lags and Productivity Growth …Connecting the Dots

The three most extensively cited papers by Zvi Griliches deal with the diffusion of innovations, distributed lags and the sources of the growth of measured total factor productivity, respectively. The close economic connections between these dynamic phenomena remained largely unexplored and were at best only implicit in his published writings until late in his career. Yet, from his later reflective writings, it is clear that Griliches not only recognized the existence of those connections, but regarded them to be critically important in understanding the determinants of the pace of economic growth. The present paper proceeds in that spirit. It examines the relationship between Gliches’ pioneering study of the diffusion of hybrid corn and the subsequent development of economic theories explaining diffusion phenomenon. Rather than offering a comprehensive survey of the literature, its aim is to expose the connections with lagged investment in capital-embodied innovations, and formalize of the micro-to macro links between technological diffusion dynamics and the pace of measured productivity growth. The heterodox, “evolutionary economics” aspects of this approach to explaining technological ‘transitions’ may be thought to be a significant yet under-appreciated part of Griliches’ intellectual legacy.

Phyllonorycter messaniella (Zeller, 1846), new record for the Maltese Islands (Lepidoptera: Gracillariidae)

Phyllonorycter messaniella is recorded for the first time from the Maltese Islands. Data about life history, ecology and distribution is included.peer-reviewe

Spatial relations, histories from below and the makings of agency: Reflections on The Making of the English Working Class at 50

In this paper we propose a conversation between work in labour history and labour geography, in part centring on the formative contribution of E.P. Thompson. We contend that the commitment to multiple and political forms of agency and working-class experience and the positioning of class as process, which are lasting contributions of The Making of the English Working Class, offer resources for re-invigorating debates on agency within labour geography and beyond. The paper scrutinizes the spatial politics at work in Thompson’s account of agency and experience through drawing on critiques of Thompson by feminist and post-colonial scholars. The paper explores the significance of Thompson’s work for asserting a spatial politics of labour and argues for attention to the diverse agentic spatial practices shaped through labour organizing and struggles. The paper concludes by setting out some key aspects of the terms of a conversation between labour geographies and labour histories