12 resultados para Weaving
em QUB Research Portal - Research Directory and Institutional Repository for Queen's University Belfast
Resumo:
Agonistic behaviour between male orb-web spiders Metellina mengei competing for access to female webs was examined in field experiments to test the major predictions of game theory. Winners of fights were significantly larger than losers, particularly with respect to the length of the first pair of legs, which are sexually dimorphic in this species and used extensively in agonistic encounters. The size of the winning male had no influence on contest intensity or duration, and neither did relative size. However, fight intensity and duration were both positively correlated with the size of the losing male. Resident males won significantly more contests than intruders. Winning intruders were significantly larger than winning residents and it was these winning intruders that tended to produce the longer fights. Female weight and hence reproductive value had a marked influence on fight intensity and duration of fights won by the intruder but not those won by the resident. This indicates that only the resident obtains information about the female. These data are discussed with reference to the discrepancy with theory and a failure of some contestants to obtain information on resource value and relative contestant size necessary to optimize fight strategy.
Resumo:
This article investigates the damage imparted on load-bearing carbon fibers during the 3D weaving process and the subsequent compaction behavior of 3D woven textile preforms. The 3D multi-layer reinforcements were manufactured on a textile loom with few mechanical modifications to produce preforms with fibers orientated in the warp, weft, and through-the-thickness directions. Tensile tests were conducted on three types of commercially available carbon fibers, 12k HTA, 6k HTS, and 3k HTS in an attempt to quantify the effect of fiber damage induced during the 3D weaving process on the mechanical and physical performance of the fiber tows in the woven composite. The tests were conducted on fiber tows sampled from different locations in the manufacturing process from the bobbin, through the creel and loom mechanism, to the final woven fabric. Mechanical and physical testing were then conducted to quantify the tow geometry, orientation and the effect of compaction during manufacture of two styles of 3D woven composite by vacuumassisted resin transfer molding (VaRTM).
Resumo:
Product Line software Engineering depends on capturing the commonality and variability within a family of products, typically using feature modeling, and using this information to evolve a generic reference architecture for the family. For embedded systems, possible variability in hardware and operating system platforms is an added complication. The design process can be facilitated by first exploring the behavior associated with features. In this paper we outline a bidirectional feature modeling scheme that supports the capture of commonality and variability in the platform environment as well as within the required software. Additionally, 'behavior' associated with features can be included in the overall model. This is achieved by integrating the UCM path notation in a way that exploits UCM's static and dynamic stubs to capture behavioral variability and link it to the feature model structure. The resulting model is a richer source of information to support the architecture development process.
Resumo:
This research presents the development of an analytical model to predict the elastic stiffness performance of orthogonal interlock bound 3D woven composites as a consequence of altering the weaving parameters and constituent material types. The present approach formulates expressions at the micro level with the aim of calculating more representative volume fractions of a group of elements to the layer. The rationale in representing the volume fractions within the unit cell more accurately was to improve the elastic stiffness predictions compared to existing analytical modelling approaches. The models developed in this work show good agreement between experimental data and improvement on existing predicted values by models published in literature.
Resumo:
The three-dimensional (3D) weaving process offers the ability to tailor the mechanical properties via design of the weave architecture. One repeat of the 3D woven fabric is represented by the unit cell. The model accepts basic weaver and material manufacturer data as inputs in order to calculate the geometric characteristics of the 3D woven unit cell. The specific weave architecture manufactured and subsequently modelled had an angle interlock type binding configuration. The modelled result was shown to have a close approximation compared to the experimentally measured values and highlighted the importance of the representation of the binder tow path.
Resumo:
An analytical modeling approach for the prediction of the geometric characteristics of five-dimensional (5D) woven composites has been formulated. The model is driven by readily available data including the weaving parameters and constituent material properties. The new model calculates the individual proportions of fiber in each direction, areal density, overall fiber volume fraction, and laminate thickness. This information is useful for the engineer in the design and manufacture of 5D woven composites. In addition the present model outputs the mathematical definition of the 5D woven composite unit cell, which could be implemented as the geometric input for a downstream analytical model that is capable of predicting the elastic stiffness of 5D woven composites. Input parameters have been sourced from existing published work and the subsequent predictions made by the model are compared with the available experimental data on 5D woven composites.
Resumo:
This book consists of eight chapters with writings on improvisation and an introduction by one of the most intriguing improvisers of our generation – Evan Parker.
The initial discussions for this book were carried out during the “Two Thousand + TEN” symposium, which took place on the 6th of November 2010 at the Sonic Arts Research Centre in Belfast. The symposium’s theme was ‘improvisation’. Georgina Born and David Borgo gave keynote addresses, alongside many other excellent speakers, several of who are included in this book.
My contribution is a novel way of editing texts, as I have woven all chapters into an overall piece of writing, interlaced with my own contribution of around 40 pages.
Resumo:
Historically in Gaelic culture, the bard was greatly valued and admired as an important and integral part of society. Travelled, schooled and specifically trained in their art, the bard helped ensure identity and reassurance for Gaelic families by grounding them both temporarily and spatially into their landscape. Entrusted with the duty and responsibility of recording place and event, the bards worked without writing and by transgressing man-made boundaries, travelled throughout the land weaving their histories into the very fabric of society.
Now no longer with us, we find ourselves without the distinguished chronicler to undertake this duty. Yet the responsibility of the Gaelic bard is one still shared by all artists today; to facilitate memory and identity, whether good or bad. Many Ulster writers, by happenstance and geography have found themselves located in a place of painful histories. An immediate difficulty for those local writers becomes manifest by being intrinsically implicated into those histories – whilst having first-hand knowledge and comprehension beyond that of the outsider, the local writer is automatically damned by association and relationship, thereby tarnishing their voice in comparison to the perceived impartiality of others.
Some writers however have successfully sought ways to escape this limitation and have worked in ways that can transgress the restrictions of prejudgement. John Hewitt, by purposely becoming a self-imposed tourist was able to distance himself to write impartially about the past, recognising that ’the place without its ghosts is a barren place.’1 In ‘The Colony’,2 tradition, peoples and mapping of the land are all narrated by Hewitt in a similar way to the Gaelic bardic topographic poems of Sean O'Dubhagain and Giolla Na Naomh O'Huidhrin3 in compiling a rich cultural atlas.
Similarly the Belfast poet and novelist Ciaran Carson also writes and records the city from an intermediary position; that of translator. Mediating between reader and aisling,4 Carson himself takes the reader on a journey into name, meaning, time and place, focusing primarily on the city of Belfast, familiar in name but impenetrable in depth to most.
Furthermore, this once-forgotten tradition to chronicle is now being continued by the new breed of Irish crime writers where the likes of Brian McGilloway, Stuart Neville and Adrian McKinty can, by way of the crime novel, accurately record contemporary society. Thus, ghost estates, listed buildings, archaeological digs, street and city have all provided setting and subject matter for recent novels. Moreover by choosing the ‘outsider from within’ as their chief protagonist, whether detective or criminal, each author is able to transgress the boundaries of prejudice and preconception that hinder genuine understanding and knowledge.
Looking in turn at the Gaelic bard, the twentieth century Ulster poet and the new breed of Irish crime writer, the authors will outline the real value of the narrator, by being able to act as cultural transgressor beyond the seeming and alleged as the true chronicler in society, and then with specific reference to city and countryside in Ireland, as a valuable custodian of knowledge in architecture and place.
Keywords
Architecture, Crime Fiction, Cultural Atlas, Place, Poetry.
1 From ‘The Bloody Brae’, a one act play written by John Hewitt in the 1930’s.
2 Hewitt, J. (1968) published in Collected Poems 1932-67. London:McGibbon & Kee.
3 Lengthy and detailed medieval Gaelic poems composed in the fourteenth and fifteenth centuries first edited by John O'Donovan in 1862 for the Irish Archaeological and Celtic Society in Dublin.
4 The aisling is the Irish song or poem genre when the poet is visited by their muse in a daydream or dream-vision state.
Resumo:
Major ampullate silk fibers of orb web-weaving spiders have impressive mechanical properties due to the fact that the underlying proteins partially fold into helical/amorphous structures, yielding relatively elastic matrices that are toughened by anisotropic nanoparticulate inclusions (formed from stacks of beta-sheets of the same proteins). In vivo the transition from soluble protein to solid fibers involves a combination of chemical and mechanical stimuli (such as ion exchange, extraction of water and shear forces). Here we elucidate the effects of such stimuli on the in vitro aggregation of engineered and recombinantly produced major ampullate silk-like proteins (focusing on structure-function relationships with respect to their primary structures), and discuss their relevance to the storage and assembly of spider silk proteins in vivo. (C) 2009 Elsevier Inc. All rights reserved.
Resumo:
Streets are key elements of urban space; they are in essence public spaces and connect diverse areas of the city weaving the urban fabric. Once motorways replace existing streets, they tear the fabric and transform the qualities of the urban landscape. As in many cities throughout the world, in Belfast during the 1960s the growth of private car ownership took over the development of the city. The Roads Authority developed plans (1964/1969) to build a ring road surrounding most of the city. This deeply affected the use and shape of the city until today. This plan focused on encouraging the move of population to the outskirts of the city. However, the connections between the city centre and its surrounding neighbourhoods were broken. Only the southern stretch of the motorway was not built. This allowed the connection between South Belfast and the city centre to remain seamless. The current possibility of building the southern stretch of motorway threatens this continuity. This paper will highlight the very high value of streets by analysing their physical qualities.