247 resultados para Ultimate bearingcapacity
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The notion of sovereignty is central to any international tax issue. While a nation is free to design its tax laws as it sees fit and raise revenue in accordance with the needs of its citizens, it is not possible to undertake such a task in isolation. Tax interactions between sovereign states cannot be avoided. Ultimately, the interactions mean that a nation must decide whether or engage in both collaboration and co ordination with other nations and supranational bodies alike or maintain a unilateral stance in relation to its tax policy. This article considers a modern conceptualisation of sovereignty to argue that a move towards a more unified approach to addressing international base erosion and profit sharing may be the ultimate exercise of national fiscal sovereignty.
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Synthetic hydrogels selectively decorated with cell adhesion motifs are rapidly emerging as promising substrates for 3D cell culture. When cells are grown in 3D they experience potentially more physiologically relevant cell-cell interactions and physical cues compared with traditional 2D cell culture on stiff surfaces. A newly developed polymer based on poly(2-oxazoline)s has been used for the first time to control attachment of fibroblast cells and is discussed here for its potential use in 3D cell culture with particular focus on cancer cells towards the ultimate aim of high throughput screening of anti-cancer therapies. Advantages and limitations of using poly(2-oxazoline) hydrogels are discussed and compared with more established polymers, especially polyethylene glycol (PEG).
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Nanostructured high strength Mg-5%Al-x%Nd alloys were prepared by mechanical alloying. Microstructural characterization reveled average crystalline size to be about 30 nm after mechanical alloying while it increased to about 90 nm after sintering and extrusion. Mechanical properties showed increase in 0.2% yield stress, ultimate tensile strength was attributed to reduction in gain size as well as to the enhanced diffusion after mechanical activation. Although ultra high yield stress was observed from the specimen with 5% Nd, its ductility was reduced to about 1.6%.
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Convective downburst wind storms generate the peak annual gust wind speed for many parts of the non-cyclonic world at return periods of importance for ultimate limit state design. Despite this there is little clear understanding of how to appropriately design for these wind events given their significant dissimilarities to boundary layer winds upon which most design is based. To enhance the understanding of wind fields associated with these storms a three-dimensional numerical model was developed to simulate a multitude of idealised downburst scenarios and to investigate their near-ground wind characteristics. Stationary and translating downdraft wind events in still and sheared environments were simulated with baseline results showing good agreement with previous numerical work and full-scale observational data. Significant differences are shown in the normalised peak wind speed velocity profiles depending on the environmental wind conditions in the vicinity of the simulated event. When integrated over the height of mid- to high rise structures, all simulated profiles are shown to produce wind loads smaller than an equivalent 10 m height matched open terrain boundary layer profile. This suggests that for these structures the current design approach is conservative from an ultimate loading standpoint. Investigating the influence of topography on the structure of the simulated near-ground downburst wind fields, it is shown that these features amplify wind speeds in a manner similar to that expected for boundary layer winds, but the extent of amplification is reduced. The level of reduction is shown to be dependent on the depth of the simulated downburst outflow.
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This paper presents the details of an experimental study of a cold-formed steel hollow flange channel beam known as LiteSteel Beam (LSB) subject to web crippling actions (ETF and ITF). Due to the geometry of the LSB, as well as its unique residual stress characteristics and initial geometric imperfections resultant of manufacturing processes, much of the existing research for common cold-formed steel sections is not directly applicable to LSB. Experimental and numerical studies have been carried out to evaluate the behaviour and design of LSBs subject to pure bending actions, predominant shear actions and combined actions. To date, however, no investigation has been conducted into the web crippling behaviour and strength of LSB sections under ETF and ITF load conditions. Hence experimental studies were conducted to assess the web crippling behaviour and strengths of LSBs. Twenty eight web crippling tests were conducted and the results were compared with the current AS/NZS 4600[1] and AISI S100 [2]design equations. Comparison of the ultimate web crippling capacities from tests showed that AS/NZS 4600[1] and AISI S100 [2] design equations are unconservative for LSB sections under ETF and ITF load cases. Hence new equations were proposed to determine the web crippling capacities of LSBs. Suitable design rules were also developed under the DSM format.
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The role of Bone Tissue Engineering in the field of Regenerative Medicine has been the topic of substantial research over the past two decades. Technological advances have improved orthopaedic implants and surgical techniques for bone reconstruction. However, improvements in surgical techniques to reconstruct bone have been limited by the paucity of autologous materials available and donor site morbidity. Recent advances in the development of biomaterials have provided attractive alternatives to bone grafting expanding the surgical options for restoring the form and function of injured bone. Specifically, novel bioactive (second generation) biomaterials have been developed that are characterised by controlled action and reaction to the host tissue environment, whilst exhibiting controlled chemical breakdown and resorption with an ultimate replacement by regenerating tissue. Future generations of biomaterials (third generation) are designed to be not only osteo- conductive but also osteoinductive, i.e. to stimulate regeneration of host tissues by combining tissue engineer- ing and in situ tissue regeneration methods with a focus on novel applications. These techniques will lead to novel possibilities for tissue regeneration and repair. At present, tissue engineered constructs that may find future use as bone grafts for complex skeletal defects, whether from post-traumatic, degenerative, neoplastic or congenital/developmental “origin” require osseous reconstruction to ensure structural and functional integrity. Engineering functional bone using combinations of cells, scaffolds and bioactive factors is a promising strategy and a particular feature for future development in the area of hybrid materials which are able to exhibit suitable biomimetic and mechanical properties. This review will discuss the state of the art in this field and what we can expect from future generations of bone regeneration concepts.
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Finite element method (FEM) relies on an approximate function to fit into a governing equation and minimizes the residual error in the integral sense in order to generate solutions for the boundary value problems (nodal solutions). Because of this FEM does not show simultaneous capacities for accurate displacement and force solutions at node and along an element, especially when under the element loads, which is of much ubiquity. If the displacement and force solutions are strictly confined to an element’s or member’s ends (nodal response), the structural safety along an element (member) is inevitably ignored, which can definitely hinder the design of a structure for both serviceability and ultimate limit states. Although the continuous element deflection and force solutions can be transformed into the discrete nodal solutions by mesh refinement of an element (member), this setback can also hinder the effective and efficient structural assessment as well as the whole-domain accuracy for structural safety of a structure. To this end, this paper presents an effective, robust, applicable and innovative approach to generate accurate nodal and element solutions in both fields of displacement and force, in which the salient and unique features embodies its versatility in applications for the structures to account for the accurate linear and second-order elastic displacement and force solutions along an element continuously as well as at its nodes. The significance of this paper is on shifting the nodal responses (robust global system analysis) into both nodal and element responses (sophisticated element formulation).
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The motion response of marine structures in waves can be studied using finite-dimensional linear-time-invariant approximating models. These models, obtained using system identification with data computed by hydrodynamic codes, find application in offshore training simulators, hardware-in-the-loop simulators for positioning control testing, and also in initial designs of wave-energy conversion devices. Different proposals have appeared in the literature to address the identification problem in both time and frequency domains, and recent work has highlighted the superiority of the frequency-domain methods. This paper summarises practical frequency-domain estimation algorithms that use constraints on model structure and parameters to refine the search of approximating parametric models. Practical issues associated with the identification are discussed, including the influence of radiation model accuracy in force-to-motion models, which are usually the ultimate modelling objective. The illustration examples in the paper are obtained using a freely available MATLAB toolbox developed by the authors, which implements the estimation algorithms described.
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The physical, emotional, educational and social developmental challenges of adolescence can be associated with high levels of emotional vulnerability. Thus, the development of effective emotion-regulation strategies is crucial during this time period. Young people commonly use music to identify, express and regulate their emotions. Modern mobile technology provides an engaging, easily accessible means of assisting young people through music. A systematic contextual review identified 20 iPhone applications addressing emotions through music and two independent raters, using the Mobile App Rating Scale (MARS), evaluated the quality of the apps. Their characteristics, key features and overall quality will be presented. Three participatory design workshops (N=13, 6 males, 7 females; age 15-25) were conducted to explore young people’s use of music to enhance wellbeing. Young people were also asked to trial existing mood and music apps and to conceptualise their ultimate mood targeting music application. A thematic analysis of the participatory design workshops content identified the following music affect-regulation strategies: relationship building, modifying cognitions, modifying emotions, and immersing in emotions. The application of the key learnings from the mobile app review and participatory design workshops and the design and development of the music eScape app were presented and implications for future research was discussed.
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Epithelial mesenchymal transition (EMT) and cancer stem cells (CSC) have been associated with resistance to chemotherapy. Eighty percent of ovarian cancer patients initially respond to platinum-based combination therapy but most return with recurrence and ultimate demise. To better understand such chemoresistance we have assessed the potential role of EMT in tumor cells collected from advanced-stage ovarian cancer patients and the ovarian cancer cell line OVCA 433 in response to cisplatin in vitro. We demonstrate that cisplatin-induced transition from epithelial to mesenchymal morphology in residual cancer cells correlated with reduced E-cadherin, and increased N-cadherin and vimentin expression. The mRNA expression of Snail, Slug, Twist, and MMP-2 were significantly enhanced in response to cisplatin and correlated with increased migration. This coincided with increased cell surface expression of CSC-like markers such as CD44, α2 integrin subunit, CD117, CD133, EpCAM, and the expression of stem cell factors Nanog and Oct-4. EMT and CSC-like changes in response to cisplatin correlated with enhanced activation of extracellular signal-regulated kinase (ERK)1/2. The selective MEK inhibitor U0126 inhibited ERK2 activation and partially suppressed cisplatin-induced EMT and CSC markers. In vivo xenotransplantation of cisplatin-treated OVCA 433 cells in zebrafish embryos demonstrated significantly enhanced migration of cells compared to control untreated cells. U0126 inhibited cisplatin-induced migration of cells in vivo, suggesting that ERK2 signaling is critical to cisplatin-induced EMT and CSC phenotypes, and that targeting ERK2 in the presence of cisplatin may reduce the burden of residual tumor, the ultimate cause of recurrence in ovarian cancer patients.
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If there is a silver lining to the adversarial, dispute-prone nature of the building and construction industry, it can be found in the concomitant rise of innovative dispute resolution mechanisms. Time, cost and relationship concerns have meant that the formal adversarial system holds little appeal for disputing parties. As these alternative forms of dispute avoidance/resolution have matured in Australia over the last 20 years, attention has turned to the key characteristics of each process and their suitability to the building and construction industry. This article considers the role of dispute review boards (DRBs) and mediation as two alternative methods for avoiding/resolving disputes in the construction industry. Criteria are established for evaluating the efficacy of these procedures and their sensitivity to the needs of construction industry disputants. The ultimate conclusion reached is that DRBs represent a powerful, yet underutilised dispute resolution tool in Australia, and possess many industry-specific advantages that more traditional forms of alternative dispute resolution (particularly mediation) do not provide.
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FROM KCWS 2011 CHAIRS AND SUMMIT PROCEEDING EDITORS In recent years, with the impact of global knowledge economy, a more comprehensive development approach has gained significant popularity. This new development approach, so called ‘knowledgebased development’, is different from its traditional predecessor. With a much more balanced focus on all of the four key development domains – economic, enviro-urban, institutional, and sociocultural – this contemporary approach, aims to bring economic prosperity, environmental sustainability and local institutional competence with a just socio-spatial order to our cities and regions. The ultimate goal of knowledge-based development is to produce a city purposefully designed to encourage the continuous production, circulation and commercialisation of social and scientific knowledge – this will in turn establish a ‘knowledge city’. A city following the ‘knowledge city’ concept embarks on a strategic mission to firmly encourage and nurture locally focussed innovation, science and creativity within the context of an expanding knowledge economy and society. In this regard a ‘knowledge city’ can be seen as an integrated city, which physically and institutionally combines the functions of a science and technology park with civic and residential functions and urban amenities. It also offers one of the effective paradigms for the sustainable cities of our time. This fourth edition of KCWS – The 4th Knowledge Cities World Summit 2011 – makes an important reminder that the 'knowledge city' concept is a key notion in the 21st Century development. Considering this notion, the Summit sheds light on the multi-faceted dimensions and various scales of building a ‘knowledge city’ via 'knowledge-based development' paradigm by particularly focusing on the overall Summit theme of ‘Knowledge Cities for Future Generations’. At this summit, the theoretical and practical maturing of knowledge-based development paradigms are advanced through the interplay between the world’s leading academics’ theories and the practical models and strategies of practitioners’ and policy makers’ drawn from around the world. This summit proceeding is compiled in order to disseminate the knowledge generated and shared in KCWS 2011 with the wider research, governance, and practice communities the knowledge cocreated in this summit. All papers of this proceeding have gone through a double-blind peer review process and been reviewed by our summit editorial review and advisory board members. We, organisers of the summit, cordially thank the members of the Summit Proceeding Editorial Review and Advisory Board for their diligent work in the review of the papers. We hope the papers in this proceeding will inspire and make a significant contribution to the research, governance, and practice circles.
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As research has become an important indicator of TEFL academics’ overall performance in Chinese higher education institutions, it is critical that TEFL academics are able to meet the expectation of conducting research. This mixed-method study (an initial survey followed by a qualitative collective case study)investigated research productivity of Chinese TEFL academics and associated influences, with the ultimate objective of constructing a framework to help build their research capacity in the future. The findings from this study revealed that the 182 Chinese TEFL academics’ research productivity during 2004-2008 was relatively low. Four influences were identified that impacted on thier research productivity: TEFL disciplinary influences, institutional and departmental research environments, individual characteristics desirable for research, and TEFL academics’ perceptions about research. Drawing upon the above findings, a Framework towards Enhancing Chinese TEFL Academics’ Research Productivity (FECTARP) was constructed. The FECTAR presented a framework for Chinese institutions and TEFL departments to enhance their TEFL academics' research capacity.
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A simple, uniquely plasma-enabled and environment-friendly process to reduce the thickness of vertically standing graphenes to only 4–5 graphene layers and arranging them in dense, ultra-large surface area, ultra-open-edge-length, self-organized and interconnected networks is demonstrated. The approach for the ultimate thickness reduction to 1–2 graphene layers is also proposed. The vertical graphene networks are optically transparent and show tunable electric properties from semiconducting to semi-metallic and metallic at room and near-room temperature, thus recovering semi-metallic properties of a single-layer graphene.
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Multiscale, multiphase numerical modeling is used to explain the mechanisms of effective control of chirality distributions of single-walled carbon nanotubes in direct plasma growth and suggest effective approaches to further improvement. The model includes an unprecedented combination of the plasma sheath, ion/radical transport, species creation/loss, plasma–surface interaction, heat transfer, surface/bulk diffusion, graphene layer nucleation, and bending/lift-off modules. It is shown that the constructive interplay between the plasma and the Gibbs–Thomson effect can lead to the effective nucleation and lift-off of small graphene layers on small metal catalyst nanoparticles. As a result, much thinner nanotubes with narrower chirality distributions can nucleate at much lower process temperatures and pressures compared to thermal CVD. This approach is validated by a host of experimental results, substantially reduces the amounts of energy and atomic matter required for the nanotube growth, and can be extended to other nanoscale structures and materials systems, thereby nearing the ultimate goal of energy- and matter-efficient nanotechnology.