290 research outputs found
Investigation into the impact of integral suppressor configurations on the pressure levels within the suppressor
This paper reports on an experimental investigation supported by basic modeling in to the performance of an integral suppressor on a low power firearm. A model was developed to determine the pressure within a suppressor chamber using iterative empirical calculations of the gas properties and flow within the system. The design of a reconfigurable suppressor chamber has been undertaken allowing suppressor chamber volume to be varied through the use of baffles. Pressure transducers were used to determine the pressure within the suppressor chamber for a series of firings. The results of the firings with different configurations within the suppressor are presented allowing trends to be established. The modeling and experimental results show an increase in suppressor chamber volume results in a reduction of recorded pressure within the suppressor chamber
Degradation of fabrics used in military fragment protective clothing due to selected laundering regimes
With the introduction of fragment protective fabrics into combat clothing, there was a need to understand the effect of laundering on the performance of these fabrics. This thesis investigated the effect of typical laundering regimes on selected ballistic protective fabrics representative of those suitable for clothing applications. This study presents evidence that knitted silk and felted ultra-high molecular weight polyethylene retained their ballistic protective performance after laundering. The para-aramid fabrics showed significant improvement from laundering. The dimensional stability of the selected fabrics was affected by laundering and the effect was cumulative. The damage imparted to the fibres was determined to be due to mechanical wear. This mechanical wear was significantly increased when the fabrics were wet. This was due to the water increasing the friction between fibres during the laundering process. The fabrics investigated were shown to be suitable for use in fragment protective clothing, and were more robust than was generally considered
A sociological analysis of intermediary non-governmental organizations and land reform in contemporary Zimbabwe
The thesis offers an original sociological understanding of intermediary Non-Governmental Organizations (NGOs) in the modern world. This is pursued through a study of NGOs and land reform in contemporary Zimbabwe. The prevailing literature on NGOs is marked by a sociological behaviourism that analyses NGOs in terms of external relations and the object-subject dualism. This behaviourism has both ‘structuralist’ and ‘empiricist’ trends that lead to instrumentalist and functionalist forms of argumentation. The thesis details an alternative conceptual corpus that draws upon the epistemological and theoretical insights of Marx and Weber. The epistemological reasoning of Marx involves processes of deconstruction and reconstruction. This entails conceptualizing NGOs as social forms that embody contradictory relations and, for analytical purposes, the thesis privileges the contradiction between ‘the global’ and ‘the local’. In this regard, it speaks about processes of ‘glocalization’ and ‘glocal modernities’ in which NGOs become immersed. The social field of NGOs is marked by ambiguities and tensions, and NGOs seek to ‘negotiate’ and manoeuvre their way through this field by a variety of organizational practices. Understanding these practices necessitates studying NGOs ‘from within’ and drawing specifically on Weber’s notion of ‘meaning’. These practices often entail activities that stabilize and simplify the world and work of NGOs, and this involves NGOs in prioritizing their own organizational sustainability. In handling the tension between ‘the global’ and ‘the local’, NGOs also tend to privilege global trajectories over local initiatives. The thesis illustrates these points in relation to the work of intermediary NGOs in Zimbabwe over the past ten years. Since the year 2000, a radical restructuring of agrarian relations has occurred, and this has been based upon the massive redistribution of land. In this respect, local empowering initiatives have dramatically asserted themselves against globalizing trajectories. These changes have posed serious challenges to ‘land’ NGOs, that is, NGOs involved in land reform either as advocates for reform or as rural development NGOs. The thesis shows how a range of diverse ‘land’ NGOs has ‘handled’ the heightened contradictions in their social field in ways that maintain their organizational coherence and integrity
Reclaiming the land: the resurgence of rural movements in Africa, Asia and Latin America
In the early 1990s, Rehman Sobhan (1993) argued that after two decades in which agrarian reform was a global non-event, ‘[vjotaries of agrarian reform’ had been reduced to ‘a fringe group of romantic throwbacks left over from the 1950s and 1960s’ (1993: p.3) He offered a broad overview of post-Second World War experiences in Asia, Latin America and Africa, and distinguished between radical and non-egalitarian reforms in terms of their effect on eliminating class differentiation and modes of domination in the countryside. He concluded by arguing that ‘ [t]he political mobilization needed to realize radical reforms in the contemporary developing world remains elusive’’ (1993: p.133, my emphasis). Nearly ten years later, Deborah Bryceson (2000), after discussing the post-Second World War academic literature on the peasantry, suggested that '[pleasant theory is on the retreat’ (2000: p.29); that it was critical to bring peasants ‘back into theoretical and policy debates’ (2000: p.30); and that the ongoing reproduction of the peasantry in Latin America, Asia and Africa through contradictory processes of formation and dissolution seemed to give them an ‘enduringpresence’ (2000: p.6). She concluded also by referring to an elusiveness, speaking about the multifaceted survival strategies of the peasantry under conditions of global neo-liberalism that make the peasantry - conceptually - ‘more elusive than before’ (2000: p.30, my emphasis). These brief comments on the status of the peasantry and agrarian reform provide an important historical and theoretical backdrop to the volume under review
NGOs and rural movements in contemporary South Africa
This article provides a critical examination of relationships between non-governmental organisations (NGOs) and rural movements in post-apartheid South Africa, particularly with regard to the possible subordination of movements to NGOs. In discussing NGOs as a particular organisational form, and in reviewing some arguments pertaining to NGOs and rural movements globally, I explore whether NGOs in South Africa have a progressive role to play in agrarian transformation
Civil society and state-centred struggles
This article is about civil society and state-centred struggles in contemporary Zimbabwe. I first identify and outline three current understandings of civil society. Two understandings (one Liberal, one Radical) are state-centric and exist firmly within the logic of state discourses and state politics. A third understanding, also Radical, is society-centric and speaks about politics existing at a distance from the state and possibly beyond the boundaries of civil society. This civil society-state discussion frames the second section of the article, which looks specifically at Zimbabwe. It details civil society as contested terrain (from the late 1990s onwards) within the context of a scholarly debate about agrarian transformation and political change. This debate, which reproduces (in theoretical garb) the key political society (or party) fault-lines within Zimbabwean society, has taken place primarily within the restricted confines of state-centred discourses
Flow network controlled shape transformation of a thin membrane through differential fluid storage and surface expansion
The mechanical properties of a thin, planar material, perfused by an embedded
flow network, can be changed locally and globally by the fluid transport and
storage, resulting in small or large-scale deformation, such as out-of-plane
buckling. Fluid absorption and storage eventually cause the material to locally
swell. Different parts can hydrate and swell unevenly, prompting a differential
expansion of the surface. In order to computationally study the hydraulically
induced differential swelling and buckling of such a membrane, we develop a
network model that describes both the membrane shape and fluid movement,
coupling mechanics with hydrodynamics. We simulate the time-dependent fluid
distribution in the flow network based on a spatially explicit resistor network
model with local fluid-storage capacitance. The shape of the surface is modeled
by a spring network produced by a tethered mesh discretization, in which local
bond rest lengths are adjusted instantaneously according to associated local
fluid content in the capacitors in a quasi-static way. We investigate the
effects of various designs of the flow network, including overall hydraulic
traits (resistance and capacitance) and hierarchical architecture (arrangement
of major and minor veins), on the specific dynamics of membrane shape
transformation. To quantify these effects, we explore the correlation between
local Gaussian curvature and relative stored fluid content in each hierarchy by
using linear regression, which reveals that stronger correlations could be
induced by less densely connected major veins. This flow-controlled mechanism
of shape transformation was inspired by the blooming of flowers through the
unfolding of petals. It can potentially offer insights for other reversible
motions observed in plants induced by differential turgor and water transport
through the xylem vessels, as well as engineering applications
Webinar: A Local to Global Imperative: Powering Personal and Societal Transformation through Education for Sustainable Development
How are postsecondary institutions empowering learners to develop the competencies for environmental integrity, equitable economic viability, and a just society while also helping them fulfil their own potential? How is this interdisciplinary work supporting transcultural values and practices as well as the development of critical global citizens? The webinar includes speakers from three postsecondary institutions engaged as partners in Regional Centres of Expertise (RCE) on Education for Sustainable Development throughout the world who will address these and related themes and explain how their institutions are carrying out this critical work.
Speakers: Sabbir Saiyed, PhD., P.Eng., Manager Transportation Systems Planning/Main Contact for the Peel RCE Rehema White, BSc, MSc, PhD, Academic in sustainable development, University of St Andrews, and Chair, Scotland’s United Nations University Regional Centre of Expertise (RCE) in Education for Sustainable Development (Learning for Sustainability Scotland) Asaf Zohar, B.A., M.E.S., PhD (York), Associate Professor, School of Business; Chair, Sustainability Studies Program; Director, Entrepreneurship and Social Innovation Centre, Trent University (RCE Peterborough Kawartha Haliburton) Marisol Campos-Navarrete, BEng, MA, PhD, Impact Learning Manager, EDGE, Sheridan’s impact entrepreneurship hub (Peel RCE)
Moderated by: John Helliker, Dean of Innovation – Sheridanhttps://source.sheridancollege.ca/cgei_events/1003/thumbnail.jp
- …