379 research outputs found
Interview with Doug Hall on the Role of Training in Innovation
In this interview, Doug Hall gives his current thinking on the teaching of innovation and the urgency for doing so. Hall has been working in the field of innovation for most of his career. He has served as partner and mentor in the University of Maine’s program which offers an Innovation Engineering minor open to undergraduate students in any major and a certificate for graduate students. Hall says that “the world of the guru is done” and that “companies, colleges, and countries need to empower their people to lead the transformation from the inside out.
Patterns of tobacco smoking among illicit drug users in Australia 2001-2010
Introduction and AimsThis study aimed to investigate whether there were changes from 2001 to 2010 in the characteristics of young adults who used party drugs or other illicit drugs and to determine if the prevalence of tobacco smoking differed depending on the type of drugs used
PVP2008-61905 EFFECTS OF NEGATIVE BIAXIAL LOADINGS AND NOTCH ON FAILURE ASSESSMENT DIAGRAMS
ABSTRACT The Failure Assessment Diagram (FAD) is a simplified and robust flaw assessment methodology which simultaneously connects two dominant failure criteria: Linear Elastic Fracture mechanics (LEFM) on one end and Plastic collapse on other end. This interaction is the realm of Elastic Plastic Fracture Mechanics (EPFM.) It is popularly known as the R6 approach which graphically characterizes the impact of plasticity on crack driving force. In the recent years, there has been continuous interest in using Failure Assessment Diagrams (FAD) to assess the failure of cracked structures subjected to biaxial loadings. Biaxiality is defined as the ratio of stress applied parallel and normal to the crack. Some aircraft components operate under negative biaxial ratios up to -0.5. In this paper, a detailed study on FAD was conducted using FEA computed J-integral methods to investigate the effect of biaxial loading using different FAD approaches for geometries with notches. Geometries with a crack that emanates at a fillet region were simulated with various biaxial loading ratios from -0.5 to +0.5 using 2014-T6 material. FAD curves were numerically generated for cracks at notched regions subjected to various biaxial loadings using J-integral values from finite element analyses and validated its practical application. Comparison studies were made between uniaxial and biaxial loading cases with FAD curves created using standard approaches for four different crack sizes. Under small scale yielding, this study clearly shows that FAD curves are not influenced by negative biaxial loading at low load (up to 40% of yield strength). It was clearly confirmed that the majority of previously developed analytical FAD curves do not effectively account for notch and plasticity effects due to negative biaxilaity. Based on this study, tension normal to the crack and compression parallel to the crack is the worst combination and it has a very pronounced effect on FAD curve shapes. The standard analytical FAD curves are nonconservative compared to the approach recommended here, particularly under the worst case condition. The proposed method is expected to predict lower failure loads relative to currently accepted analytical methods. . INTRODUCTION There are several structural integrity assessment methodologies available in predicting a critical state of cracked structural components. The Failure Assessment Diagram (FAD) is one of the popular two criteria failure approaches which represent the range of material behavior from brittle fracture to plastic collapse. In the recent past, there have been increasing interest on FAD [1-3] subjected to biaxial loading but most are based on uniaxial or positive biaxial loading conditions. Biaxiality is defined as the ratio of stress applied parallel and normal to the crack. A large amount of information is available in the open literature but the majority are based on uniaxial stress state condition
Supporting Learning and Teaching in Primary Education
The book is aimed at all those studying on Foundation Degrees in supporting primary and early years teaching and learning, and particularly those working at levels 4 and 5. It is written in an accessible style with a focus on work-based professional development and encourages critical reflection throughout. It starts with a discussion of reflective practice, and includes helpful guidance on developing effective study skills. Each chapter then focuses on a key topic in education, learning and development, considers any relevant policies and legislation, examines educational theories in relation to professional practice and provides concise case studies to contextualise the learning. It provides up-to-date and relevant material on supporting the new national curriculum, safeguarding, SEN and inclusion issues, and schools as organisations. It also covers the competencies for Higher Level Teaching Assistants
All twist and no bend makes raft edges splay: Spontaneous curvature of domain edges in colloidal membranes
Using a combination of theory and experiments we study the interface between
two immiscible domains in a colloidal membrane composed of rigid rods of
different lengths. Geometric considerations of rigid rod packing imply that a
domain of sufficiently short rods in a background membrane of long rods is more
susceptible to twist than the inverse structure, a long-rod domain in a
short-rod membrane background. The tilt at the inter-domain edge forces splay,
which in turn manifests as a spontaneous edge curvature whose energetics are
controlled by the length asymmetry of constituent rods. A thermodynamic model
of such tilt-curvature coupling at inter-domain edges explains a number of
experimental observations, including a non-monotonic dependence of the edge
twist on the domain radius, and annularly shaped domains of long rods. Our work
shows how coupling between orientational and compositional degrees of freedom
in two-dimensional fluids give rise to complex shapes and thermodynamics of
domains, analogous to shape transitions in 3D fluid vesicles.Comment: 36 pages, 8 figure
Strategic analysis of the drought resilience of water supply systems
Severe droughts can result in shortages of water supplies, with widespread social and economic consequences. Here we use a coupled simulation model to assess the reliability of public water supplies in England, in the context of changing scenarios of water demand, water regulation and climate change. The coupled simulation model combines climate simulations, a national-scale hydrological model and a national-scale water resource systems model to demonstrate how extreme meteorological droughts translate into hydrological droughts and water shortages for water users. We use this model to explore the effectiveness of strategic water resource options that are being planned in England to secure water supplies to most of England's population up to a drought return period of 1 in 500 years. We conclude that it is possible to achieve a 1-in-500-years standard in locations where strategic resource options are used, while also reducing water abstraction to restore the aquatic environment. However, the target will be easier to achieve if effective steps are also taken to reduce water demand. This article is part of the Royal Society Science+ meeting issue ‘Drought risk in the Anthropocene’
BAL Outflow Contribution to AGN Feedback: Frequency of S iv Outflows in the SDSS
We present a study of Broad Absorption Line (BAL) quasar outflows that show S
IV ?1063 and S IV* ?1073 troughs. The fractional abundance of S IV and C IV
peak at similar value of the ionization parameter, implying that they arise
from the same physical component of the outflow. Detection of the S IV* troughs
will allow us to determine the distance to this gas with higher resolution and
higher signal-to-noise spectra, therefore providing the distance and energetics
of the ubiquitous C IV BAL outflows. In our bright sample of 156 SDSS quasars
14% show C IV and 1.9% S IV troughs, which is consistent with a fainter
magnitude sample with twice as many objects. One object in the fainter sample
shows evidence of a broad S IV trough without any significant trough present
from the excited state line, which implies that this outflow could be at a
distance of several kpc. Given the fractions of C IV and S IV, we establish
firm limits on the global covering factor on S IV that ranges from 2.8% to 21%
(allowing for the k-correction). Comparison of the expected optical depth for
these ions with their detected percentage suggests that these species arise
from common outflows with a covering factor closer to the latter.Comment: Published in ApJ (2012 ApJ, 750, 143
DONALD:<i>A 2.5 T wide sample space permanent magnet</i>
The permanent magnet apparatus described herein is based upon the C-shaped permanent magnet. It is designed to maximise field strength while increasing the pole gap to 5 mm, providing a sample volume large enough for wide applicability. The production of this equipment aims to provide a homogeneous, high field (∼2.5 T) magnetic sample environment with a volume large enough to accommodate solution crystallisation experiments in sample chambers such as NMR tubes and cuvettes whilst simultaneously allowing direct observation of the sample from a wide angle. Although the resulting rig is not lightweight at 26.5 kg it is eminently more portable than an equivalent electromagnet system (of the order of 625 kg), and provides a max field strength of 2.468 T with relatively low stray field. Keywords: Permanent magnet, Sample environment, Horse-shoe magne
Alzheimer\u27s disease and vascular dementia in developing countries: prevalence, management, and risk factors
Despite mortality due to communicable diseases, poverty, and human conflicts, dementia incidence is destined to increase in the developing world in tandem with the ageing population. Current data from developing countries suggest that age-adjusted dementia prevalence estimates in 65 year olds are high (≥5%) in certain Asian and Latin American countries, but consistently low (1–3%) in India and sub-Saharan Africa; Alzheimer\u27s disease accounts for 60% whereas vascular dementia accounts for ∼30% of the prevalence. Early-onset familial forms of dementia with single-gene defects occur in Latin America, Asia, and Africa. Illiteracy remains a risk factor for dementia. The APOE ε4 allele does not influence dementia progression in sub-Saharan Africans. Vascular factors, such as hypertension and type 2 diabetes, are likely to increase the burden of dementia. Use of traditional diets and medicinal plant extracts might aid prevention and treatment. Dementia costs in developing countries are estimated to be US$73 billion yearly, but care demands social protection, which seems scarce in these regions
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