57 resultados para warp knitted fabric


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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.

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This paper presents a practical algorithm for the simulation of interactive deformation in a 3D polygonal mesh model. The algorithm combines the conventional simulation of deformation using a spring-mass-damping model, solved by explicit numerical integration, with a set of heuristics to describe certain features of the transient behaviour, to increase the speed and stability of solution. In particular, this algorithm was designed to be used in the simulation of synthetic environments where it is necessary to model realistically, in real time, the effect on non-rigid surfaces being touched, pushed, pulled or squashed. Such objects can be solid or hollow, and have plastic, elastic or fabric-like properties. The algorithm is presented in an integrated form including collision detection and adaptive refinement so that it may be used in a self-contained way as part of a simulation loop to include human interface devices that capture data and render a realistic stereoscopic image in real time. The algorithm is designed to be used with polygonal mesh models representing complex topology, such as the human anatomy in a virtual-surgery training simulator. The paper evaluates the model behaviour qualitatively and then concludes with some examples of the use of the algorithm.

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The hawari (local communities) of Old Cairo resemble a unique societal context whose history is actively involved in the contemporary everyday production of local habits, traditions and social practice. By the virtue of its durability and ability to survive, Architecture brings events and traditions of the past alive into the present through the spatial transformation, social practice and the value of the historical-fabric. The presence of buildings and houses from different historical periods has helped the local community’s memory to carry social practices over from one generation to another. This article explores the relationship between architecture, memory and everyday social practices through determining the way architecture moderates community experiences and communicates narratives among generations in haret al-Darb al-Asfar in old Cairo. Architecture emerges as a moderator of cross-time communication and as physical elements that help visualize history, situate values and materialize local traditions in old Cairo. Architecture, as process and product this article reports, works as agent of continuity, which in conjunction with the narrators, brings the full experience of the past alive in the present and helps guide future generations.

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Despite the compelling parallels between George Sand’s Laura; ou, le voyage dans le cristal and Jules Verne’s Voyage au centre de la Terre (both 1864), Sand’s place within the intertextual fabric of Verne’s novel has been occluded. By shifing the terms of the debate away from the vexed issues of borrowing, influence, or inspiration, and focusing on Verne’s sustained engagement with Sand’s work as a specifically geological fiction, this article sheds new light on the imbrication of the scientific and the fictional in Voyage au centre de la Terre, whereby geological and palaeontological references not only guarantee the text’s verisimilitude and underwrite its didactic objectives, but also fulfil an important metatextual function.

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We propose a new approach for the inversion of anisotropic P-wave data based on Monte Carlo methods combined with a multigrid approach. Simulated annealing facilitates objective minimization of the functional characterizing the misfit between observed and predicted traveltimes, as controlled by the Thomsen anisotropy parameters (epsilon, delta). Cycling between finer and coarser grids enhances the computational efficiency of the inversion process, thus accelerating the convergence of the solution while acting as a regularization technique of the inverse problem. Multigrid perturbation samples the probability density function without the requirements for the user to adjust tuning parameters. This increases the probability that the preferred global, rather than a poor local, minimum is attained. Undertaking multigrid refinement and Monte Carlo search in parallel produces more robust convergence than does the initially more intuitive approach of completing them sequentially. We demonstrate the usefulness of the new multigrid Monte Carlo (MGMC) scheme by applying it to (a) synthetic, noise-contaminated data reflecting an isotropic subsurface of constant slowness, horizontally layered geologic media and discrete subsurface anomalies; and (b) a crosshole seismic data set acquired by previous authors at the Reskajeage test site in Cornwall, UK. Inverted distributions of slowness (s) and the Thomson anisotropy parameters (epsilon, delta) compare favourably with those obtained previously using a popular matrix-based method. Reconstruction of the Thomsen epsilon parameter is particularly robust compared to that of slowness and the Thomsen delta parameter, even in the face of complex subsurface anomalies. The Thomsen epsilon and delta parameters have enhanced sensitivities to bulk-fabric and fracture-based anisotropies in the TI medium at Reskajeage. Because reconstruction of slowness (s) is intimately linked to that epsilon and delta in the MGMC scheme, inverted images of phase velocity reflect the integrated effects of these two modes of anisotropy. The new MGMC technique thus promises to facilitate rapid inversion of crosshole P-wave data for seismic slownesses and the Thomsen anisotropy parameters, with minimal user input in the inversion process.

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This paper investigates the limitations of postcolonial planning practices that aimed to modernise Cairo’s urban spaces during Gamal Abdel Nasser rule (1952–70). Following the Free Officers revolution of 1952, ambition to display urban order through forceful change in the city’s built environment was in action. Nasser’s visions of modernity were explicit in a series of attempts to reshape several prime locations in central Cairo, which included the old traditional waterfront quarter, in Bulaq Abul Ela. An analysis of the Bulaq planning scheme drafted in 1966 reveals insights into how notions of order were spatialised to integrate with Cairo’s complex urban fabric. The official plans to regularise Bulaq also strongly demonstrates how this was a top-down, centralised process in terms of governance, with full utilisation of state resources, namely the military and the media. From a wider perspective, planning practices under Nasser demonstrated an evident break with the past to eliminate memories of colonisation and disorder. Drawing on original resources, archival material, meeting minutes and maps of this historical but dilapidated quarter of Cairo, this paper gives an insight into how Nasser’s government attempted to convey a sense of order in a revolutionary country without, however, having an understanding of order as a coherent, multilayered and sequential process of change.

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This chapter examines Cairo’s path towards reassembling a modern spatial order in one of its oldest quarters, Bulaq Abul Ela, and the implications of this on the spatial experience of its inhabitants. The ambitions of space reproduction in Cairo are revealed during the attempt to engender a debate as to how this vision affected Bulaq’s riverfront zone as its periphery; how it was spatialised and to what extent the planners’ conception of urban space actually responded to the people’s needs when creating a new spatial reality. It uncovers the peripheral/central position that residents assume with regards to their living spaces to reveal new meanings, images, stories and places to replace the increasingly undesirable authentic fabric of Bulaq.

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Abstract: A vibrant inner city parish needed space for meetings, language classes, children’s play and other support accommodation as well as a clearer link between the interior of the listed church and the space outside.

The project builds itself about the entrance to the church. The form is manipulated such that the intervention recedes from those entering the church, drawing them into the plan before becoming readable as an addition. The resultant poché between this entrance sequence and the fabric of the church is hollowed out to provide the required accommodation. These rooms are insulated and lined in cork to allow for their use separate to the main body of the church. With budget at a premium the construction methodology was developed from an analysis of traditional Irish boat building techniques, which allowed the use of the solid timber to act as the primary structure with no additional material support.

Constructed in solid walnut the intervention reads with the existing brick interior and yet is clearly identifiable as a contemporary addition.

Aims / Objectives Questions

1 To accommodate new space inside an existing protected structure.
2 To form a new threshold between interior and exterior.
3 To develop an affordable means of construction that would be durable and rapid to erect.
4 To make a contemporary addition in sympathy with the qualities of the existing protect structure, in line with best conservation practice and research.
5 Traditional forms of construction as a model for contemporary technologies.

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Violence can threaten individual wellbeing and tear at the social fabric of communities. At the same time, suffering can mobilize social coping and mutual support. Thus, the backdrop of political violence increases risk factors and stimulates resilience. The current study examined the moderating role of social coping as reflective of risk and resiliency in Northern Ireland, a setting of protracted conflict. Specifically, structural equation modeling was used to investigate whether social coping protects from or exacerbates the negative impact of sectarian crime and nonsectarian crime on maternal mental health (N?=?631). Nonsectarian crime predicted greater psychological distress for mothers in Belfast. Mixed support was found for the buffering and depletion moderation hypotheses; social coping functioned differently for nonsectarian crime and sectarian crime. Greater social coping buffered mothers' psychological distress from the negative effects of nonsectarian crime, but exacerbated maternal mental health problems when facing sectarian crime. Results suggest that social coping is a complex phenomenon, particularly in settings of protracted political violence. Implications for interventions aimed at alleviating psychological distress by enhancing mothers' social coping in contexts of intergroup conflict are discussed. We would like to thank the many families in Northern Ireland who have participated in the project. We would also like to express our appreciation for the project staff, graduate students, and undergraduate students at the University of Notre Dame and the University of Ulster. A special thanks to Cindy Bergeman and Dan Lapsley for feedback on earlier drafts of this manuscript. This research was supported by NICHD grant 046933-05 to the E. Mark Cummings.

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Groundwater flow in hard-rock aquifers is strongly controlled by the characteristics and distribution of structural heterogeneity. A methodology for catchment-scale characterisation is presented, based on the integration of complementary, multi-scale hydrogeological, geophysical and geological approaches. This was applied to three contrasting catchments underlain by metamorphic rocks in the northern parts of Ireland (Republic of Ireland and Northern Ireland, UK). Cross-validated surface and borehole geophysical investigations confirm the discontinuous overburden, lithological compartmentalisation of the bedrock and important spatial variations of the weathered bedrock profiles at macro-scale. Fracture analysis suggests that the recent (Alpine) tectonic fabric exerts strong control on the internal aquifer structure at meso-scale, which is likely to impact on the anisotropy of aquifer properties. The combination of the interpretation of depth-specific hydraulic-test data with the structural information provided by geophysical tests allows characterisation of the hydrodynamic properties of the identified aquifer units. Regionally, the distribution of hydraulic conductivities can be described by inverse power laws specific to the aquifer litho-type. Observed groundwater flow directions reflect this multi-scale structure. The proposed integrated approach applies widely available investigative tools to identify key dominant structures controlling groundwater flow, characterising the aquifer type for each catchment and resolving the spatial distribution of relevant aquifer units and associated hydrodynamic parameters.

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With increasing demands on storage devices in the modern communication environment, the storage area network (SAN) has evolved to provide a direct connection allowing these storage devices to be accessed efficiently. To optimize the performance of a SAN, a three-stage hybrid electronic/optical switching node architecture based on the concept of a MPLS label switching mechanism, aimed at serving as a multi-protocol label switching (MPLS) ingress label edge router (LER) for a SAN-enabled application, has been designed. New shutter-based free-space multi-channel optical switching cores are employed as the core switch fabric to solve the packet contention and switching path conflict problems. The system-level node architecture design constraints are evaluated through self-similar traffic sourced from real gigabit Ethernet network traces and storage systems. The extension performance of a SAN over a proposed WDM ring network, aimed at serving as an MPLS-enabled transport network, is also presented and demonstrated.

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Weathering of stone is one of the major reasons for the damage of stone masonry structures and it takes place due to interlinked chemical, physical and biological processes in stones. The key parameters involved in the deterioration processes are temperature, moisture and salt. It is now known that the sudden variations in temperature and moisture greatly accelerate the weathering process of the building stone fabric. Therefore, in order to monitor these sudden variations an effective and continuous monitoring system is needed. Furthermore, it must consist of robust sensors which are accurate and can survive in the harsh environments experienced in and around masonry structures. Although salt penetration is important for the rate of deterioration of stone masonry structures, the processes involved are much slower than the damage associated with temperature and moisture variations. Therefore, in this paper a novel fibre optic temperature cum relative humidity sensor is described and its applicability in monitoring building stones demonstrated. The performance of the sensor is assessed in an experiment comprising wetting and drying of limestone blocks. The results indicate that the novel fibre optic relative humidity sensor which is tailor made for applications in masonry structures performed well in wetting and drying tests, whilst commercial capacitance based sensors failed to recover during the drying regime for a long period after a wetting regime. That is, the fibre optic sensor has the capability to measure both sorption and de-sorption characteristics of stone blocks. This sensor is used in a test wall in Oxford and the data thus obtained strengthened the laboratory observations.

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A vibrant inner city parish needed space for meetings, language classes, children’s play and other support accommodation as well as a clearer link between the interior of the listed church and the space outside.

The project builds itself about the entrance to the church. The form is manipulated such that the intervention recedes from those entering the church, drawing them into the plan before becoming readable as an addition. The resultant poché between this entrance sequence and the fabric of the church is hollowed out to provide the required accommodation. These rooms are insulated and lined in cork to allow for their use separate to the main body of the church. With budget at a premium the construction methodology was developed from an analysis of traditional Irish boat building techniques, which allowed the use of the solid timber to act as the primary structure with no additional material support.

Constructed in solid walnut the intervention reads with the existing brick interior and yet is clearly identifiable as a contemporary addition.

Aims / Objectives Questions

1 To accommodate new space inside an existing protected structure.
2 To form a new threshold between interior and exterior.
3 To develop an affordable means of construction that would be durable and rapid to erect.
4 To make a contemporary addition in sympathy with the qualities of the existing protect structure, in line with best conservation practice and research.
5 Traditional forms of construction as a model for contemporary technologies.


Principal Investigator: Clancy Moore Architects –Colm Moore

Co-investigator(s): Andrew Clancy, Mathew O’Malley

Funding partner/ Client: Select Vestry of St George and St Thomas

Finance. €35’000

Date (start – finished) Start June 2008 – Completed December 2008

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Egypt’s Revolution of 1952 presented a major historical change to its political and economic structure, its society, and its institutions. This paper examines how Nasser’s regime operated through the state apparatus to exhibit features of modernity. Under the pretext of modernization, renovating Cairo’s authentic urban fabric was one of the channels that displayed the new ambitions to unveil a centralized system of governance and ideologies of socialism. The paper particularly looks at the city’s resurgence attempts, promoted by upgrading practices that displayed Western ideals of planning. Eventually, the contradictory planning legislative system introduced by the government raised early alarms at the problems encountered in the planning institution that was not only unable to liberate Cairo’s urban districts from its long-rooted decay, but also struggled to implement the regime’s flagship policy of social justice in a context wherein it was much needed.

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The commonly used British Standard constant head triaxial permeability (BS) test, for permeability testing of fine grained soils, is known to have a relatively long test duration. Consequently, a reduction in the required time for permeability test provides potential cost savings, to the construction industry (specifically, for use during Construction Quality Control (CQA) of landfill mineral liners). The purpose of this article is to investigate and evaluate alternative short duration testing methods for the measurement of the permeability of fine grained soils.

As part of the investigation the feasibility of an existing method of short duration permeability test, known as the Accelerated Permeability (AP) test was assessed and compared with permeability measured using British Standard method (BS) and Ramp Accelerated Permeability (RAP). Four different fine grained materials, of a variety of physical properties were compacted at various moisture contents to produced analogous samples for testing using three the three different methodologies. Fabric analysis was carried out on specimens derived from post-test samples using Mercury Intrusion Porosimetry (MIP) and Scanning Electron Microscope (SEM) to assess the effects of testing methodology on soil structure. Results showed that AP testing in general under predicts permeability values derived from the BS test due to large changes in structure of the soil caused by AP test methodology, which is also validated using MIP and SEM observations. RAP testing, in general provides an improvement to the AP test but still under-predicts permeability values. The potential savings in test duration are shown to be relatively minimal for both the AP and RAP tests.