4,808 research outputs found
A comparison of the predictions of a finite element model and multiscale model for a rough MEMS electrical contact
Rough surface contact is difficult to model effectively due to multiple scales of detail that need to be considered. This work presents the results of a multiscale rough surface contact model in comparison to a finite element based deterministic model for the electrical contact of a MEMS microswitch. The real area of contact and electrical contact resistance are predicted and compared as a function of normal load. The results show good quantitative and qualitative correlation between the two methods. As expected, the contact area increases nominally linearly with load, while the contact resistance decreases with load. It is notable though that the contact pressure is up to 16% higher than the hardness (2.8 times yield strength), and could be even higher for other surfaces
The Prioritization of and Time Spent on Fundraising Duties by Public Comprehensive University Presidents
This article focuses on the prioritization of and time spent by public comprehensive university presidents on their fundraising duties. This research is a component of a larger, more comprehensive study completed in 2012 entitled, The American Public Comprehensive University: An Exploratory Study of The President’s Role in Fundraising.
This research is timely since public universities, which educate nearly 80% of all college students in America, are going through a period of great change. They are struggling to balance their budgets as states further reduce higher education appropriations. Specifically, state appropriations for public universities are at their lowest point in 30 years, having declined by about one-third since 1980; and there is no end in sight to this funding dilemma.
Although academic fundraising has occurred for centuries, this new decline in state support for public comprehensive universities has prompted presidents to turn to alumni, friends, corporations, and foundations for private funds with new and increased fundraising efforts to redress lost state appropriations. This alteration in the funding model during the past several years has changed the primary duties of university presidents
Daze fasteners
A daze fastener system for connecting two or more structural elements wherein the structural elements and fastener parts have substantially different coefficient of thermal expansion physical property characteristics is employed in this invention. By providing frusto-conical abutting surfaces between the structural elements and fastener parts any differences in thermal expansion/contraction between the parts is translated to sliding motion and avoids deleterious thermal stresses in the connection. An essential feature for isotropic homogeneous material connections is that at least two sets of mating surfaces are required wherein each set of mating surfaces has line element extensions that pass through a common point
Cryogenic Insulation System
This invention relates to reusable, low density, high temperature cryogenic foam insulation systems and the process for their manufacture. A pacing technology for liquid hydrogen fueled, high speed aircraft is the development of a fully reusable, flight weight cryogenic insulation system for propellant tank structures. In the invention cryogenic foam insulation is adhesively bonded to the outer wall of the fuel tank structure. The cryogenic insulation consists of square sheets fabricated from an array of abutting square blocks. Each block consists of a sheet of glass cloth adhesively bonded between two layers of polymethacrylimide foam. Each block is wrapped in a vapor impermeable membrane, such as Kapton(R) aluminum Kapton(R), to provide a vapor barrier. Very beneficial results can be obtained by employing the present invention in conjunction with fibrous insulation and an outer aeroshell, a hot fuselage structure with an internal thermal protection system
The evaluation of PE Personnel 1992: a report of a values-based evaluation of a competitive employment training and placement service for people with disabilities: purpose, methodology, outcomes and recommendations
Late in 1991, the Managing Director of PE Personnel, Ms Susan Robertson, approached the Director of the Centre for the Development of Human Resources (CDHR) at Edith Cowan University, Mr Errol Cocks, to discuss the possibility of an evaluation for PE Personnel. Over a period of three or four months, the purposes and shape of a proposed evaluation developed through clarification and negotiation, and in March, 1992, an agreement was reached for Mr Cocks and Mr Bob Jackson from the CDHR to carry out the evaluation. The results of the evaluation, as described in this report, cover the period up to 30 June 1992.
A decision was made that the evaluation would be qualitative and would be underpinned by a clear values base which would focus on the use of the service users. Initially, discussion centred on the use of PASSING (Wolfensberger & Thomas, 1983), an evaluation and teaching instrument based on Social Role Valorization (Wolfensberger, 1992). Eventually it was decided to utilise some of the PASSING Ratings, but to focus particularly on the coherency of the service. The concept of coherency is contained in particular evaluation ratings in both PASSING and PASS (Wolfensberger & Glenn, 1975), an evaluation instrument which preceded the development of PASSING
Radiation therapy for neovascular age-related macular degeneration
Antivascular endothelial growth factor (anti-VEGF) therapies represent the standard of care for most patients presenting with neovascular (wet) age-related macular degeneration (neovascular AMD). Anti-VEGF drugs require repeated injections and impose a considerable burden of care, and not all patients respond. Radiation targets the proliferating cells that cause neovascular AMD, including fibroblastic, inflammatory, and endothelial cells. Two new neovascular AMD radiation treatments are being investigated: epimacular brachytherapy and stereotactic radiosurgery. Epimacular brachytherapy uses beta radiation, delivered to the lesion via a pars plana vitrectomy. Stereotactic radiosurgery uses low voltage X-rays in overlapping beams, directed onto the lesion. Feasibility data for epimacular brachytherapy show a greatly reduced need for anti-VEGF therapy, with a mean vision gain of 8.9 ETDRS letters at 12 months. Pivotal trials are underway (MERLOT, CABERNET). Preliminary stereotactic radiosurgery data suggest a mean vision gain of 8 to 10 ETDRS letters at 12 months. A large randomized sham controlled stereotactic radiosurgery feasibility study is underway (CLH002), with pivotal trials to follow. While it is too early to conclude on the safety and efficacy of epimacular brachytherapy and stereotactic radiosurgery, preliminary results are positive, and these suggest that radiation offers a more durable therapeutic effect than intraocular injections
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Isolation, characterisation and experimental evolution of phage that infect the horse chestnut tree pathogen, Pseudomonas syringae pv. aesculi
Bleeding canker of horse chestnut trees is a bacterial disease, caused by the bacterium Pseudomonas syringae pv. aesculi, estimated to be present in ~ 50% of UK horse chestnut trees. Currently, the disease has no cure and tree removal can be a common method of reducing inoculum and preventing spread. One potential method of control could be achieved using naturally occurring bacteriophages infective to the causative bacterium. Bacteriophages were isolated from symptomatic and asymptomatic horse chestnut trees in three locations in the South East of England. The phages were found to be belonging to both the Myoviridae and Podoviridae families by RAPD PCR and transmission electron microscopy. Experimental coevolution was carried out to understand the dynamics of bacterial resistance and phage infection and to determine whether new infective phage genotypes would emerge. The phages exhibited different coevolution patterns with their bacterial hosts across time. This approach could be used to generate novel phages for use in biocontrol cocktails in an effort to reduce the potential emergence of bacterial resistance
ASTRO Journals' Data Sharing Policy and Recommended Best Practices.
Transparency, openness, and reproducibility are important characteristics in scientific publishing. Although many researchers embrace these characteristics, data sharing has yet to become common practice. Nevertheless, data sharing is becoming an increasingly important topic among societies, publishers, researchers, patient advocates, and funders, especially as it pertains to data from clinical trials. In response, ASTRO developed a data policy and guide to best practices for authors submitting to its journals. ASTRO's data sharing policy is that authors should indicate, in data availability statements, if the data are being shared and if so, how the data may be accessed
21st Century STEM Reasoning
The Georgia Southern University Real STEM Project is collaborating with 10 middle and high schools on development and implementation of an interdisciplinary STEM research and design course that actively engages students in real-world problem solving. We will discuss the expected outcomes of such interdisciplinary STEM experiences which is the development of 21st century STEM reasoning. Examples of using authentic teaching strategies to promote complex systems reasoning, model-based reasoning, computational reasoning, engineering design-based reasoning, and quantitative reasoning will be shared with participants
A Plastic Stress Analysis Of Cylindrical Wafers Under Elastically Deformable Compression Plates
This paper represents an analysis of the pressure distribution occurring in axially loaded cylindrical wafers with, and without, elastic radial constraints. The purpose of this report is to demonstrate the resulting stress patterns that occur in short compression specimens frequently used in determining material properties, and in the opposed-anvil, or Bridgman-type, high-pressure cells. The influence of radial constraints, material strain hardening, wafer diameter-to-height ratio, anvil or plate deflection, and the wafer-anvil interface friction on the resulting stress distributions have been examined. The integrated normal stress distribution across the specimen surface has been verified experimentally via numerous tests in which each of the subject parameters listed above was varied. © 1967 by ASME
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