2,718 research outputs found
Finite Element Programme Development for the Analysis of Precast Flooring and Roofing System
At the initial stage of this study an attempt was made to write a computer programme
for the analysis and design of precast floor slabs on the FORTRAN language, which
is compatible with FORTRAN 90 Power Station. The programme considers various
types of precast reinforced concrete slabs such as solid slab (one-way and two-way),
hollow core slab, ribbed slab and composite slab. The programme consists of a main
and several subroutines. The programme was written according to BS 8110 and was
verified by using it to analyse a few examples. The software is capable of analysing
and designing different floor slabs with a provision for generating the optimal crosssection
and plotting the cross section graphically. Further, the effect of different
design parameters on the solid slab, hollow slab and ribbed slab design had been
presented.
One of the main objectives of this study was the development of a finite element
code using the semi-loof beam and shell elements. The application of these elements
to model the precast flooring and roofing system was illustrated. The validity of the
developed programme was established by analysing some benchmark problems and comparing the results with those from a commercial package. The results indicate
that the use of the semi-loof elements resulted in a powerful programme, which is
suitable for the analysis of complex shell type structures.
Another primary objective of this investigation was the analysis of a composite slab,
which consisted of precast and insitu layers. There was a need to model two different
materials along with their interface characteristic. An interface element sandwiched
between two 16-noded isoparametric brick element has been formulated. This
interface element was used in an existing three dimensional finite element package.
The behaviour of the composite slab under load with respect to displacements,
stresses and strains was studied. It was found that it was important to model frictional
behaviour between the two different materials as in composite slabs
Narrating regions: New Storytelling technique helps increasing people's analysis and information sharing
Sound information at sub-national level and benchmarking of regions across national borders has increased in importance in the policy agenda of many countries due to higher integration driven by institutional processes and economic globalisation. Geovisual analytics techniques help illustrating complex data such as regional, spatiotemporal and multidimensional statistics. Interactive time-linked visual representations enable the users to simultaneously analyse relations among different variables. "OECD eXplorer", developed by NCVA in collaboration with OECD, is today a worldwide recognized web-enabled tool for visualizing and better understanding the socio-economic structure of OECD regions and their performance over time. Geovisual Analytics in the OECD explorer has so far focused more on tools to analyse regional economic performance than on methods that efficiently publish gained knowledge. Publication is indeed part of the analytical process and it could become a catalyst for discussion generating new value in a social setting. In this context, we introduce a novel storytelling that supports the editorial authoring process with the goal to advance technology critical to the sharing of information and publishing. With the introduction of this new technique, we are moving away from a clear distinction between authors and readers: The analyst can discuss with interested readers the visual discoveries which have been captured into snapshots together with descriptive text and hyperlinks. The author gets feedback from colleagues, adapts the story and publishes it using a "Vislet" that is embedded in blogs or wikis. This advanced storytelling technology applied to OECD eXplorer can therefore become a complete on-line publication to highlight recent trends and relevant disparities among OECD regions
High speed InAs electron avalanche photodiodes overcome the conventional gain-bandwidth product limit
High bandwidth, uncooled, Indium Arsenide (InAs) electron avalanche photodiodes (e-APDs) with unique and highly desirable characteristics are reported. The e-APDs exhibit a 3dB bandwidth of 3.5 GHz which, unlike that of conventional APDs, is shown not to reduce with increasing avalanche gain. Hence these InAs e-APDs demonstrate a characteristic of theoretically ideal electron only APDs, the absence of a gain-bandwidth product limit. This is important because gain-bandwidth products restrict the maximum exploitable gain in all conventional high bandwidth APDs. Non-limiting gain-bandwidth products up to 580 GHz have been measured on these first high bandwidth e-APDs. (C) 2011 Optical Society of Americ
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Influence of trace erythromycin and eryhthromycin-H2O on carbon and nutrients removal and on resistance selection in sequencing batch reactors (SBRs).
Three sequencing batch reactors (SBRs) were operated in parallel to study the effects of trace erythromycin (ERY) and ERY-H2O on the treatment of a synthetic wastewater. Through monitoring (1) daily effluents and (2) concentrations of nitrogen (N) and phosphorous (P) in certain batch cycles of the three reactors operated from transient to steady states, the removal of carbon, N, and P was affected negligibly by ERY (100 microg/L) or ERY-H2O (50 microg/L) when compared with the control reactor. However, through analyzing microbial communities of the three steady state SBRs on high-density microarrays (Phylo-Chip), ERY, and ERY-H2O had pronounced effects on the community composition of bacteria related to N and P removal, leading to diversity loss and abundance change. The above observations indicated that resistant bacteria were selected upon exposure to ERY or ERY-H2O. Shortterm batch experiments further proved the resistance and demonstrated that ammonium oxidation (56-95%) was inhibited more significantly than nitrite oxidation (18-61%) in the presence of ERY (100, 400, or 800 microg/L). Therefore, the presence of ERY or ERY-H2O (at microg/L levels) shifted the microbial community and selected resistant bacteria, which may account for the negligible influence of the antibiotic ERY or its derivative ERY-H2O (at microg/L levels) on carbon, N, and P removal in the SBRs
A Data-driven Approach Towards Human-robot Collaborative Problem Solving in a Shared Space
We are developing a system for human-robot communication that enables people
to communicate with robots in a natural way and is focused on solving problems
in a shared space. Our strategy for developing this system is fundamentally
data-driven: we use data from multiple input sources and train key components
with various machine learning techniques. We developed a web application that
is collecting data on how two humans communicate to accomplish a task, as well
as a mobile laboratory that is instrumented to collect data on how two humans
communicate to accomplish a task in a physically shared space. The data from
these systems will be used to train and fine-tune the second stage of our
system, in which the robot will be simulated through software. A physical robot
will be used in the final stage of our project. We describe these instruments,
a test-suite and performance metrics designed to evaluate and automate the data
gathering process as well as evaluate an initial data set.Comment: 2017 AAAI Fall Symposium on Natural Communication for Human-Robot
Collaboratio
A serious adverse surgical event: Management of suspected HSV-1 keratitis in a donor cornea.
PurposeTo describe the management of a serious adverse event in a patient undergoing penetrating keratoplasty (PK).Case reportA 68-year-old man underwent PK for an aphakic bullous keratopathy following previous complicated cataract surgery. He had no past history of herpetic disease. Storage of the corneoscleral disc in the transport bottle precluded microscopic examination. After placement of the trephined donor cornea on the open eye of the recipient, a large dendritiform geographic ulcer was noted on the donor cornea. A replacement cornea was used after changing potentially contaminated instruments. Intravenous antiviral treatment was commenced intraoperatively to reduce the risk of infection to the central nervous system. Postoperatively, oral and topical antiviral treatment was commenced and 6 months following surgery the patient developed a geographic corneal ulcer at the graft host interface.ConclusionContainers to transport corneoscleral discs should enable microscopic examination by the surgeon prior to use. High dose systemic antivirals may reduce the risk of herpetic disease involving the posterior segment of the eye and neuroretina in the aphakic eye and spread to the central nervous system
People learn other people's preferences through inverse decision-making
People are capable of learning other people's preferences by observing the choices they make. We propose that this learning relies on inverse decision-making -- inverting a decision-making model to infer the preferences that led to an observed choice. In Experiment 1, participants observed 47 choices made by others and ranked them by how strongly each choice suggested that the decision maker had a preference for a specific item. An inverse decision-making model generated predictions that were in accordance with participants' inferences. Experiment 2 replicated and extended a previous study by Newtson (1974) in which participants observed pairs of choices and made judgments about which choice provided stronger evidence for a preference. Inverse decision-making again predicted the results, including a result that previous accounts could not explain. Experiment 3 used the same method as Experiment 2 and found that participants did not expect decision makers to be perfect utility-maximizers
A High Efficiency Aluminum-Ion Battery Using an AlCl3-Urea Ionic Liquid Analogue Electrolyte
In recent years, impressive advances in harvesting renewable energy have led
to pressing demand for the complimentary energy storage technology. Here, a
high coulombic efficiency (~ 99.7%) Al battery is developed using
earth-abundant aluminum as the anode, graphite as the cathode, and a cheap
ionic liquid analogue electrolyte made from a mixture of AlCl3 and urea in 1.3
: 1 molar ratio. The battery displays discharge voltage plateaus around 1.9 V
and 1.5 V (average discharge = 1.73 V) and yielded a specific cathode capacity
of ~73 mAh g-1 at a current density of 100 mA g-1 (~ 1.4 C). High coulombic
efficiency over a range of charge-discharge rates and stability over ~150-200
cycles was easily demonstrated. In-situ Raman spectroscopy clearly showed
chloroaluminate anion intercalation/deintercalation of graphite in the cathode
side during charge/discharge and suggested the formation of a stage 2 graphite
intercalation compound when fully charged. Raman spectroscopy and nuclear
magnetic resonance suggested the existence of AlCl4-, Al2Cl7- anions, and
[AlCl2. (urea)n]+ cations in the urea/AlCl3 electrolyte when an excess of AlCl3
was present. Aluminum deposition therefore proceeded through two pathways, one
involving Al2Cl7- anions and the other involving [AlCl2.(urea)n]+ cations. This
battery is a promising prospect for a future high performance, low cost energy
storage device
Profibrinolytic effect of the epigenetic modifier valproic acid in man.
To access publisher's full text version of this article, please click on the hyperlink in Additional Links field or click on the hyperlink at the top of the page marked Files.
This article is open access.The aim of the study was to test if pharmacological intervention by valproic acid (VPA) treatment can modulate the fibrinolytic system in man, by means of increased acute release capacity of tissue plasminogen activator (t-PA) as well as an altered t-PA/Plasminogen activator inhibitor -1 (PAI-1) balance. Recent data from in vitro research demonstrate that the fibrinolytic system is epigenetically regulated mainly by histone deacetylase (HDAC) inhibitors. HDAC inhibitors, including VPA markedly upregulate t-PA gene expression in vitro.The trial had a cross-over design where healthy men (n = 10), were treated with VPA (Ergenyl Retard) 500 mg depot tablets twice daily for 2 weeks. Capacity for stimulated t-PA release was assessed in the perfused-forearm model using intra-brachial Substance P infusion and venous occlusion plethysmography. Each subject was investigated twice, untreated and after VPA treatment, with 5 weeks wash-out in-between. VPA treatment resulted in considerably decreased levels of circulating PAI-1 antigen from 22.2 (4.6) to 10.8 (2.1) ng/ml (p<0.05). It slightly decreased the levels of circulating venous t-PA antigen (p<0.05), and the t-PA:PAI-1 antigen ratio increased (p<0.01). Substance P infusion resulted in an increase in forearm blood flow (FBF) on both occasions (p<0.0001 for both). The acute t-PA release in response to Substance P was not affected by VPA (p = ns).Valproic acid treatment lowers plasma PAI-1 antigen levels and changes the fibrinolytic balance measured as t-PA/PAI-1 ratio in a profibrinolytic direction. This may in part explain the reduction in incidence of myocardial infarctions by VPA treatment observed in recent pharmacoepidemiological studies.The EU Clinical Trials Register 2009-011723-31.Swedish Heart-Lung Foundation
Swedish Research Council
Emelle Foundatio
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