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Social Impact Bonds and the Perils of Aligned InterestsMaier, Florentine, Meyer, Michael 15 July 2017 (has links) (PDF)
Social impact bonds (SIBs) have been welcomed enthusiastically as a new funding tool for social innovation, yet also condemned as an instrument that neglects beneficiaries' and taxpayers' interests, opening profit opportunities in the field of social politics for smart private investors. We will shed a more analytical light on SIBs, assuming that, like any contract, SIBs try to align interests between partners with partly converging, partly diverging goals. Thus, it remains mainly a matter of negation, and non-profit social service providers as well as public agencies should avoid particular perils and pitfalls.
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Fluid characterisation and drop impact in inkjet printing for organic semiconductor devicesJung, Sungjune January 2011 (has links)
An inkjet printer can deposit a very small volume of liquid with high positional accuracy, high speed and low cost. As a maskless, non-contact additive patterning method, inkjet printing technology is increasingly being explored as an alternative to lithography, etching and vapour deposition processes to pattern electrical conductors and thin films with applications in printed electronic devices. The functional inks used in many of the applications involve non-linear viscoelasticity and their behaviours in the context of inkjet printing have not been fully understood. This thesis aims to characterise Newtonian and non-Newtonian properties of inkjet fluids and identify the key parameters affecting drop impact and spreading processes. Various fluid characterisation techniques such as the filament stretching rheometer and piezoelectric axial vibrator are explored. We propose an experimental method to assess the jettability of non-Newtonian inkjet fluids, without using an inkjet print head. The oblique collision of two continuous liquid jets leads to the formation of a thin oval liquid sheet bounded by a thicker rim which disintegrates into ligaments and droplets. Under certain conditions the flow structure exhibits a remarkably symmetrical 'fishbone' pattern composed of a regular succession of longitudinal ligaments and droplets. Good correlation was found between the maximum included angle of the fishbone pattern and the maximum ligament length in the jetting experiments, which suggests that a test based on oblique impinging jets may be useful in the development of fluids for ink jet printing. High-speed imaging is used to analyse the impact and spreading of sub-30 μm drops of diethyl phthalate or polystyrene solutions in diethyl phthalate on to smooth glass surfaces with controlled wettability at speeds from 3 to 8 m s-1, under conditions representative of drop-on-demand inkjet printing. Data on drop height and spreading diameter are generated with high time and spatial resolution, over eight orders of magnitude in timescale. The effects of fluid viscosity and elasticity, which significantly affect jetting performance, are negligible throughout the whole deposition process, with no significant difference between spreading curves. The values of the fluid surface tension and the substrate wettability also have no effect on the kinematic, spreading or relaxation phases, but a marked influence on the wetting phase, in terms of the speed of expansion of the contact diameter and the final spreading factor.
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Effect of microstructure on mechanical properties of high strength steel weld metalsKeehan, Enda January 2004 (has links)
The effects of variations in alloying content on the microstructure and mechanical properties of high strength steel weld metals have been studied. Based on neural network modelling, weld metals were produced using shielded metal arc welding with nickel at 7 or 9 wt. %, manganese at 2 or 0.5 wt. % while carbon was varied between 0.03 and 0.11 wt. %. From mechanical testing, it was confirmed that a large gain in impact toughness could be achieved by reducing the manganese content. Carbon additions were found to increase strength with only a minor loss to impact toughness as predicted by the modelling. The highest yield strength (912 MPa) in combination with good impact toughness (over 60 J at -100 °C) was achieved with an alloying content of 7 wt. % nickel, 0.5 wt. % manganese and 0.11 wt. % carbon. Based on thermodynamic calculations and observed segregation behaviour it was concluded that the weld metals solidify as austenite. The microstructure was characterised using optical, transmission electron and high resolution scanning electron microscopy. At interdendritic regions mainly martensite was found. In dendrite core regions of the low carbon weld metals a mixture of upper bainite, lower bainite and a novel constituent - coalesced bainite - formed. Coalesced bainite was characterised by large bainitic ferrite grains with cementite precipitates and is believed to form when the bainite and martensite start temperatures are close to each other. Carbon additions were found to promote a more martensitic microstructure throughout the dendrites. Mechanical properties could be rationalised in terms of microstructural constituents and a constitutional diagram was constructed summarising microstructure as a function of manganese and nickel contents.
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Speed and temperature effects in the energy absorption of axially crushed composite tubesFontana, Quentin P. V. January 1990 (has links)
Tubes of glass reinforced thermosetting resins have been tested in axial compression between steel platens with one end chamfered to prevent critically high loads causing catastrophic centre failure. By testing in such a manner these tubes crush in a progressive and controlled manner, and are capable of exhibiting high levels of energy absorption, particularly when related to the material mass involved. Polymers are known to display viscoelastic behaviour and polymer composites are similarly sensitive to test speed and temperature. Energy absorption in tube crushing has been shown to be speed and temperature sensitive and the purpose of this project has been to understand the variability of the energy absorption and the associated mechanisms. The main aim has been to show how the two variables interrelate. The materials used have been produced by hot rolling of pre-preg cloth or by resinjection into closed moulds. Reinforcement has consisted of woven glass cloth or random glass mat; matrix materials have been epoxy and polyester resins. Trends to higher values of specific energy absorption with increasing speed have been observed for epoxy matrix tubes, while polyester matrix tubes have shown less certain trends and give lower values of specific energy absorption at high speeds. All the tubes have shown a rapid drop in specific energy absorption with increasing temperature above normal room temperature, with changes in crush mode being very apparent. At temperatures in excess of about 100 degrees C the tubes have failed by centre buckling, the transition temperature from normal crushing to buckling being sensitive to the crush speed. The interrelation between speed and temperature effects has been examined. Three factors that prevent simple interrelation have been identified; these are inertial effects of crush debris, residual stresses in the hoop direction of the tube and frictional heating in the crush zone. Speed sensitivity of the energy absorption has been determined over a range of temperatures and various features of these responses related to the responses of the material properties. Frictional temperature rises have been modelled mathematically and the predictions have been shown to be reasonably consistent with experimental measurements. These temperature rises have been shown to be important in determining the speed sensitive behaviour of the energy absorption levels, particularly for polyester resin matrix tubes tested at high speeds.
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The Economic Impact of Recurrent Coagulopathy in Crotaline EnvenomationsHolden-Traynor, Leslie January 2008 (has links)
Class of 2008 Abstract / Objectives: To determine the ecomomic impact of recurrent coagulopathy with crotaline envenomation, using the current standard of care (crotalinae polyvalent immune Fab antivenom), and establish a model of pharmacoeconmic assessment for future studies. Methods: Design of recurrent coagulopathy cost assessment tool including payor costs and patient costs. Using medical and medical billing references, government websites, business websites, and published studies, determine average costs for major variables affecting the cost of recurrent coagulopathy to the payor and the patient.
Results: A prospective study has been designed to take place during the historic height of Arizona snake bite season in 2008.
Conclusions: Based on previous studies of recurrent coagulopathy an estimated 45-53% of crotaline envenomation patients can expect to experience recurrent coagulopathy after treatment with crotalinae polyvalent immune Fab antivenom. The economic impact to the payor is expected to be high with laboratory costs of $49.45 each, doctor visits costing $66.02, emergency room visits costing $351, and $3563.75 per vial of crotalinae polyvalent immune Fab antivenom. Historically the cost of recurrent coagulopathy to the patient has not been evaluated. Considering lost wages, transportation to and from medical care, and the cost of additional household help and child care, this cost is expected to be great enough to adversely impact individuals and families.
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Environmental impact assessment and its role in regional development planningTanner, Diane Janet January 1985 (has links)
This study documents strengths and weaknesses inherent in Environmental Impact Assessment (EIA), as currently practiced at the federal level in Canada. Two case studies are examined—the Beaufort Sea hydrocarbon development and production Environmental Assessment and Review Process (EARP), and the West Coast offshore hydrocarbon exploration EIA (a joint federal/provincial review). By examining current strengths and weaknesses valuable lessons can be learned and utilized in adapting the role of EIA within wider planning processes. The major objective of this study is to determine how the West Coast EIA can contribute to a more considered approach to development planning in the West Coast region.
The study reviews relevant literature on planning and EIA to provide information on theoretical relationships between EIA and planning. This provided a basis for evaluating strengths and weaknesses of the Beaufort Sea EARP. The West Coast EIA was compared and contrasted to the Beaufort Sea EARP to determine what lessons had been learned from the latter review. Based on this evaluation, suggestions were made on ways in which the West Coast EIA, principally through the panel's recommendations, could contribute both to improvements in EARP, and to effective planning and management of West Coast offshore hydrocarbon resources.
Evaluation of the two case studies revealed that there are both strengths and weaknesses evident in EIA. Major strengths are the comprehensive scope of the reviews, public involvement, and, in the case of the Beaufort Sea EARP, the provision of intervenor funding, and, a unique opportunity to examine government's management capability.
Both EIAs are affected by similar external circumstances--the lack of a coordinated policy and planning framework, and outstanding native claims. The Beaufort Sea EARP panel failed to make the most of its opportunity to address the partial policy and planning vacuum. The West Coast EIA panel still has an opportunity to address the partial vacuum within which it is operating.
The Beaufort Sea EARP and West Coast EIA both examine preliminary project proposals associated with hydrocarbon activities. However, the Beaufort Sea EARP panel provided little guidance on how such preliminary EIAs should be handled in future, or recommendations on subsequent project specific EIA requirements. The thesis suggests ways in which the West Coast EIA can avoid repeating this deficiency.
There is a definite weakness in EARP procedure. As a one-shot approach, EARP focuses on the product (the Environmental Impact Statement) rather than on environmental management as an ongoing, continuous process. Thus, the Beaufort Sea EIA process ended after the panel submitted its Final Report, and it appears that the same will apply for the West Coast. EIA review. Consequently, there is no guarantee that management-oriented monitoring, which should be an integral part of EIA, will be undertaken. This study concludes that if the West Coast EIA is to make a valuable contribution to regional development planning the panel should more fully utilize the information it receives than previous panels have done. Moreover, it must clearly establish and document in its Final Report the major issues and concerns impeding orderly development of the region. How will these concerns interfere with hydrocarbon exploration and other resource uses? How can governments act to resolve these outstanding issues? This requires going beyond merely documenting future data and research requirements to a consideration of the policy, planning and institutional requirements for rational development of West Coast resources.
I suggest several major issues deserving of focused attention: lack of a coordinated regional planning framework; project need assessment; jurisdictional dispute; outstanding native claims; future project specific EIA requirements; community involvement in future assessments; monitoring; intervenor funding; and compensation. The panel, of course, may uncover other issues and concerns. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
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The causes of scientific disputes in impact assessment and management : the Utah mines caseMartin, Brian Randall January 1985 (has links)
This thesis identifies the causes of disputes between scientists who are involved in environmental impact assessment and management (EIAM), and suggests some critical elements of scientific dispute resolution processes, particularly peer review. It does this within the context of a case study, the environmental assessment, monitoring, and management of the Island Copper Mine marine tailings discharge into Rupert Inlet, B.C. The events of this case are analysed, drawing on literature on the scientist's role in impact assessment and management, and on the philosophy and sociology of science literature.
The case study and literature review indicate that the causes of such scientific disputes are complex. The complexity and uncertainty of the physical and biological processes of a fjord system are one cause. Logistical failings in integrating scientists into the process are another: poor timing of scientists' efforts; failures of communication; and lack of accountability are examples. Poor methodology and inadequate research design also caused disputes. The transdisciplinary nature of the scientific problems common to EIAM causes disagreements of a different nature-- over the relevance of various disciplines' research foci to the problem at hand, and over what constitutes acceptable scientific practice. Value and interest conflicts between scientists, which influence both the trajectory of research and the interpretation of its results, complete the typology of the causes of disputes.
The thesis recommends the elements of peer review processes necessary to resolve these disputes. Peer review should be pre-emptive, by focussing on research design where possible, and should be representative of the range of relevant scientific disciplines, and should facilitate constructive solutions rather than the defense of positions. / Applied Science, Faculty of / Community and Regional Planning (SCARP), School of / Graduate
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An Overview of Body Armor and Single Plate Impact DynamicsMatzinger, Thomas 01 February 2018 (has links)
In the past, personal body armor was constructed of simple plates of high- strength alloys. However, with the advancement of modern combat and weaponry, particularly armor-piercing ammunition, personal body armor has evolved into more complex and effective metal, ceramic, and composite structures. This paper lays the groundwork for experimental and modeling methods used to understand the effectiveness of new armor designs. Focusing on the first layer of modern body armor, the ”High Impedance” layer. Experiments measuring the change in velocity of bullets passing through aluminum and titanium plates were conducted. These experiments were then replicated through FEA simulation.
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High Speed Imaging of Splashing by Fuel Droplet Impacts inside Combustion EngineAldawood, Hussain 12 1900 (has links)
The impact of fuel drops on the walls of combustion chambers is unavoidable in direct-injection automotive engines. These drop-solid interactions can lead to splashing of the lubrication oil, its dilution or removal, which can damage the piston or the liner from dewetting. This can also cause irregular and inferior combustion or soot formation. Understanding the drop-splashing dynamics is therefore important, especially as modern IC engines are being down-sized to achieve higher thermal efficiency. Typical cylinders of IC engines contain metal liners on their walls, which have fine azimuthal grooves to support the lubricating oil as the piston moves inside the cylinder. In this thesis we study how these grooves affect the deposition or splashing of impacting diesel drops, while the solid surface is kept dry without the lubricating oil. For these experiments we use sections of actual cylinder liners and apply high-speed video imaging to capture the details of the drop impacts.
The first set of experiments used normal impacts on horizontal substrates. These experiments include a range of drop sizes and impact velocities, to identify impact conditions in Reynolds and Weber number space where the transition from deposition to splashing occurs. We also study the maximum radial spreading factor of the impact lamella, finding about 8% larger spreading along the grooves than perpendicular to them.
In the second set of experiments we look at the impact on inclined substrates, where the inclination angle is between 30o–60o. This produces strong asymmetry in the maximum spreading, with the tangential velocity governing the maximum radial motion.
The inclined impacts change the splashing threshold, requiring larger impact velocities for splashing. The splashing threshold deviates quantitatively from earlier theories, but shows the same qualitative trends. Furthermore, a new splashing mechanism is observed, where the impact forms a prominent ejecta crown from the downstream edge. This crown ruptures first from the grooves at the sides and subsequently the capillarity detaches the downstream levitated liquid sheet from the substrate generating a myriad of splashed droplets.
Preliminary observations with impacts on wet substrates show much stronger crown-formation from the lubricating oil film, with potential for dewetting.
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Porovnání výše obvyklého nájemného z bytů ve vybrané lokalitě / Comparison of Rents of Flats in a Chosen AreaIvanič, Matej January 2010 (has links)
The thesis deals with leases in the region of Brno, the breakdown of the various districts and particularly in the various locations, including characteristics that affect these leases. In each selected municipality of 10 flats are selected in each category for the winter and examined 10 categories of housing for the summer period. Districts were selected to best represent the geographical breakdown of the city of Brno to the north and south. The data are statistically evaluated and incorporated into the graphics. Thus, the data obtained are intended for practical use for the valuation of yield method.
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