Polymer fibre composites : investigation into performance enhancement through viscoelastically generated pre-stress

In this research, the performance and further development of viscoelastically pre-stressed polymer matrix composites (VPPMCs) was investigated. Pre-stressed composite samples with continuous unidirectional fibres are produced by applying a tensile load to polymeric fibres to induce tensile creep. After removing the load, the fibres are moulded in a polyester resin. Following resin curing, compressive stresses are imparted by the viscoelastically strained fibres as they attempt to recover their strain against the surrounding solid matrix material. Prior to this study, VPPMCs using nylon 6,6 fibres increased impact energy absorption and flexural modulus by 30-50% relative to control (un-stressed) counterparts. The current work contributes to ongoing efforts in VPPMC research by expanding the knowledge of existing VPPMC materials and identifying the potential for an alternative, mechanically superior polymeric fibre.For nylon 6,6 fibre-based VPPMCs, the effects of Charpy impact span settings and fibre volume fraction (3-17% Vf) were investigated. The effects of commingling nylon pre-stressing fibres with Kevlar fibres to produce hybrid VPPMCs was also evaluated. Moreover, as an alternative to nylon fibre, the viscoelastic characteristics and subsequent VPPMC performance of polyethylene (UHMWPE) fibre was investigated. Charpy impact and three-point bend tests were used to evaluate VPPMC samples against control (un-stressed) counterparts. In addition, microscopy techniques were applied to impact-tested samples, to analyse fracture behaviour.For the nylon fibre-based VPPMCs, it was found that improvements in impact energy absorption from pre-stress depended principally on shear stresses activating fibre-matrix debonding during the impact process. Scanning electron microscopy of impact-tested samples revealed visual evidence of pre-stress impeding crack propagation. A short span setting (24 mm) showed greater increases in energy absorption of 25-40%, compared with samples tested at a larger span (60 mm) which gave increases of 0-13%. The results suggest that there is an increasing contribution to energy absorption from elastic deflection at larger span settings; this causes lower energy absorption as well as reducing any improvements from pre-stress effects. However, this effect was suppressed by the addition of Kevlar fibres (to produce hybrid VPPMCs), which promoted more effective energy absorption at the larger span. Moreover, bend tests on the hybrid composites demonstrated that pre-stressing further enhanced flexural modulus by ~35%.The viscoelastic characteristics of UHMWPE fibres indicated that these fibres could release stored energy for pre-stressing over a long time period. This was effectively demonstrated with UHMWPE fibre-based VPPMCs using three-point bend tests, i.e. flexural modulus increased by 25-35% from pre-stressing with no deterioration observed over the time scale investigated (~2 years). Also, these VPPMCs absorbed ~20% more impact energy than their control counterparts, with some batches reaching 30-40%. Although fibre-matrix debonding is known to be a major energy absorption mechanism, this was not evident in the UHMWPE fibre-based VPPMCs. Instead, evidence of debonding at the skin-core interface within the UHMWPE fibres was found. This is believed to be a previously unrecognised energy absorption mechanism.This work contributes to a further understanding of the viscoelastic properties of polymeric fibres and insight into the field of pre-stressed composite materials. The findings support the view that VPPMCs can provide a means to improve impact toughness and other mechanical characteristics for composite applications

Islam and the Trajectory of Globalization

The book examines the growing tension between social movements that embrace egalitarian and inclusivist views of national and global politics, most notably classical liberalism, and those that advance social hierarchy and national exclusivism, such as neoliberalism, neoconservatism, and national populism. In exploring issues relating to tensions and conflicts around globalization, the book identifies historical patterns of convergence and divergence rooted in the monotheistic traditions, beginning with the ancient Israelites that dominated the Near East during the Axial age, through Islamic civilization, and finally by considering the idealism-realism tensions in modern times. One thing remained constant throughout the various historical stages that preceded our current moment of global convergence: a recurring tension between transcendental idealism and various forms of realism. Transcendental idealism, which prioritize egalitarian and universal values, pushed periodically against the forces of realism that privilege established law and power structure. Equipped with the idealism-realism framework, the book examines the consequences of European realism that justified the imperialistic venture into Africa, the Middle East, and Latin America in the name of liberation and liberalization. The ill-conceived strategy has, ironically, engendered the very dysfunctional societies that produce the waves of immigrants in constant motion from the South to the North, simultaneously as it fostered the social hierarchy that transfer external tensions into identity politics within the countries of the North. The book focuses particularly on the role played historically by Islamic rationalism in translating the monotheistic egalitarian outlook into the institutions of religious pluralism, legislative and legal autonomy, and scientific enterprise at the foundation of modern society. It concludes by shedding light on the significance of the Muslim presence in Western cultures as humanity draws slowly but consistently towards what we may come to recognize as the Global Age. The Open Access version of this book, available at http://www.taylorfrancis.com/books/e/9781003203360, has been made available under a Creative Commons Attribution-Non Commercial-No Derivatives 4.0 license

Transnational Archipelago

The island nation of Cape Verde has given rise to a diaspora that spans the four continents of the Atlantic Ocean. Migration has been essential to the island since the birth of its nation. This volume makes a significant contribution to the study of international migration and transnationalism by exploring the Cape Verdean diaspora through its geographic diversity and with a broad thematic range.De eilandgemeenschap Kaapverdië heeft een diaspora veroorzaakt die zo ver strekt als de vier continenten rond de Atlantische Oceaan. Sinds het ontstaan van de gemeenschap is migratie een essentieel onderdeel van het dagelijkse leven op Kaapverdië gebleken. Verbindingen met een gebied dat ver weg ligt, blijft ook vandaag de dag het dagelijkse leven op het eiland domineren. Dit boek draagt in belangrijke mate bij aan de studie naar internationale migratie en transnationalisme door de diaspora van de bewoners van Kaapverdië te onderzoeken op geografische diversiteit vanuit een breed thematisch perspectief. Transnational Archipelago is tot stand gekomen met bijdragen van twintig wetenschappers uit verschillende disciplines

Transnational Archipelago

The island nation of Cape Verde has given rise to a diaspora that spans the four continents of the Atlantic Ocean. Migration has been essential to the island since the birth of its nation. This volume makes a significant contribution to the study of international migration and transnationalism by exploring the Cape Verdean diaspora through its geographic diversity and with a broad thematic range

Power from the people: the empowerment of distributed generation of solar electricity for rural communities in Malaysia

This paper describes the decreasing energy security in Malaysia and the likely impact on maintaining power supplies to low income groups. The most vulnerable group is the low-income people in the rural areas, who have limited access to generate their own power supplies. The paper reviews the potential of distributed generation (DG) using photovoltaics as a means of mitigating this problem. Examples from other countries are reviewed and alternative methods of funding PV installations are discussed. Strategies such as community-based approach and innovative financing scheme will be introduced and discussed. The main objective is to utilize solar energy as the main energy resources for generating electricity and places rural people as the main stakeholder to deploy the strategic model. This model is also ideal to be integrated with the distributed generation (DG) system as one of the key components in developing a suitable energy policy that can helps to sustain the energy development of rural community in the future. The paper concludes that distributed generation (DG) is feasible and that innovative funding schemes are required based on local knowledge

Sustainability through subsistence: the case for de-urbanization in Malaysia

Industrialization was the catalyst for the growth of cities in Southeast Asia, in particular Malaysia. However, in many cities industrialization has peaked and is now declining. This raises the issue of increased urban poverty as a significant problem facing these cities in the 21st century. Evidence from other developing countries is that faced with the choice of urban poverty or rural subsistence, there appears to be a trend towards de-urbanization. As Malaysia is unique in imposing laws that protect rural land ownership, this study investigates the capacity of the available land to absorb migrants from the city and seeks to identify whether the returning migrants have the capabilities required to maintain a subsistence lifestyle. This paper presents a case study analyzing the trends of urban to rural migration in Malaysia. An audit of land capacity was carried out in a typical kampong and an investigation of the capability of migrants has been done in both urban and rural areas. In conclusion, this study has found that the land abandoned by the rural-urban migration of the 1970s is available and remains accessible for future use. The findings also identified several examples of returnees who have shown that they have adapted well to a rural lifestyle. The results indicate that there is evidence that de-urbanization can result in a sustainable lifestyle through subsistence living in Malaysia

Crisis communication and framing: A study of the food safety issues in Taiwan

This study examines the three food oil crises that occurred in Taiwan between 2013 and 2014, when over a thousand food products were recalled and more than two hundred supermarkets, restaurants and food makers were affected; these crises led the Taiwanese government to revise food production regulations. The main purpose of this study is to explore how the Taiwanese government, the three companies involved (the Chang Chi company, the Chang Guann company, and the Ting Hsin company), and the Taiwanese media framed the crises and what crisis response strategies were embedded in the frames. This study draws upon crisis communication theories and framing theory to develop a theoretical framework, and applies a qualitative framing analysis method to examine the three companies’ and the Taiwanese government’s official press releases and three Taiwanese daily newspapers. Five frames have been identified in the public communication of the three main actors during the crises: ‘health’, ‘economy’, ‘responsibility’, ‘denial’, and ‘blame’. The study finds that the three edible oil companies intensely relied on the ‘denial’, ‘blame’ and ‘responsibility’ frames to respond to the crises. The Taiwanese government focused on the ‘blame’, ‘health’ ‘responsibility’ and ‘economy’ frames when framing the crises. Besides, the ‘blame’, ‘health’ and ‘economy’ frames were presented in the media reports. In addition, the study finds that the three main actors in this study adjusted their crisis response on the basis of other actors’ crisis responses. Finally, the study suggests redefining the crisis response strategy of ‘apology’, and including ‘silence’ as a crisis response strategy when research is based on Taiwanese or Chinese culture

The linguistic doctrine of Thomas Aquinas and its relevance to modern linguistics.

This thesis compares the traditional logico-philosophic approach to language as found in the writings of Thomas Aquinas, with contemporary scientific linguistics, for the first time. To date, only two authors, P. Manthey and V. Warnach, have dealt with Aquinas' linguistic doctrine in detail. Their works are cited in the bibliography. Neither of these authors is acquainted with scientific linguistics, and neither evaluates or criticizes Aquinas' work. By giving the historical background of the questions about language which Aquinas discussed, and by putting his views into the complex of philosophic, psychological, logical, grammatical and scientific work which was their setting, some of the criteria still implicit in traditional grammar become clearer. By setting out the difference between descriptive and explanatory categories as Aquinas saw it, some of the methodological differences between traditional grammar and scientific linguistics, as well as the possibility of their synthesis, emerge. This study should be of interest to linguists for the following reasons; (a) it is clear that the findings of scientific linguistics are readily assimilable into Aquinas' synthesis; (b) Aquinas' principles supply a justification for the autonomy of linguistic science; (c) Aquinas' position is mid-way between the "God's Truth" and "Hocus-pocus" attitudes toward linguistic description, and (d) a knowledge of Aquinas' work is helpful in clarifying some problems of interest to linguists, such as the status of linguistic abstractions and the treatment of meaning