634 research outputs found
On a Generalized Matching Problem Arising in Estimating the Eigenvalue Variation of Two Matrices
It is shown that if G is a graph having vertices P1, P2, ..., Pn, Q1, Q2, ..., Qn and satisfying some conditions, then there is a permutation σ of {1, 2, ..., n} such that there is a path, for i = 1, 2, ..., n connecting Pi with Qσ(i) having a length at most {n/2}. This is used to prove a theorem having applications in eigenvalue variation estimation
Thermomechanical deformation behavior and mechanisms in transition metal carbides
Mechanical testing over 2000oC is arduous because of the required heating, compliance in components, and potential specimen reactions to name a few. In this talk, the use of a non-contact means of thermomechanical loading, initially demonstrated by Gangireddy and Halloran, is applied to TaC and HfC. By passing a current through the carbide, it is resistively heated and, in the presence of a magnetic field, the specimen bends under the Lorentz force. Using a variety of loads and temperatures up to 3000oC, the thermomechanical behavior is quantified for a series of tantalum and hafnium carbides. Findings include more deflection in TaC than HfC at equivalent load/temperatures which is contributed to TaC’s ease of {111} slip. At failure, TaC exhibited abnormal grain growth with multiple slip band formations on the fractured surface. In contrast, HfC exhibited minimal grain growth and substantially less slip band formations. Additional studies determining the relationship between load at failure as a function of temperature were determined. The collective results will be discussed in terms of TEM and DFT analysis of slip mechanisms in transition metal carbides
Phone-based presentation of other commuters’ subjective experiences: impact on car-driver intentions
Previous research demonstrates that people using active modes of transport (e.g. walking or cycling) generally report more positive subjective wellbeing than car drivers. This study demonstrates an experiment investigating the impact of this information on car drivers. We designed a smartphone application (CommuterExperience), which captures drivers’ subjective experiences (via comments and ratings) after the commute and displays similar data from other people using different modes of transport. After a two week trial, participants (n=18) were interviewed and qualitative data were analysed. We evaluate how the application managed to encourage comparison, foster reflection and ultimately influence opinions, intentions to change and, potentially, behaviour
Spin induced multipole moments for the gravitational wave flux from binary inspirals to third Post-Newtonian order
Using effective field theory techniques we calculate the source multipole
moments needed to obtain the spin contributions to the power radiated in
gravitational waves from inspiralling compact binaries to third Post-Newtonian
order (3PN). The multipoles depend linearly and quadratically on the spins and
include both spin(1)spin(2) and spin(1)spin(1) components. The results in this
paper provide the last missing ingredient required to determine the phase
evolution to 3PN including all spin effects which we will report in a separate
paper.Comment: 35 pages, 7 figures. Published versio
A bayesian multilevel modeling approach for data query in wireless sensor networks
In power-limited Wireless Sensor Network (WSN), it is important to reduce the communication load in order to achieve energy savings. This paper applies a novel statistic method to estimate the parameters based on the realtime data measured by local sensors. Instead of transmitting large real-time data, we proposed to transmit the small amount of dynamic parameters by exploiting both temporal and spatial correlation within and between sensor clusters. The temporal correlation is built on the level-1 Bayesian model at each sensor to predict local readings. Each local sensor transmits their local parameters learned from historical measurement data to their cluster heads which account for the spatial correlation and summarize the regional parameters based on level-2 Bayesian model. Finally, the cluster heads transmit the regional parameters to the sink node. By utilizing this statistical method, the sink node can predict the sensor measurements within a specified period without directly communicating with local sensors. We show that this approach can dramatically reduce the amount of communication load in data query applications and achieve significant energy savings
Relationships between traditional and fundamental dough-testing methods
Two fundamental test systems were used to evaluate the visco-elastic properties of doughs from wheat samples of three varieties grown at four distinct sites. For comparison, tests were also performed with traditional equipment, namely the Mixograph, an extension tester and a Farinograph-type small-scale recording mixer. Uniaxial dough elongation (with an Instron) produced results similar to the conventional extension tester, except that results were provided in fundamental units (Pascals), the critical value recorded being the elongational stress at maximum strain. Stress relaxation measurements were performed following a small initial shear strain. With this method, it was possible to distinguish between the viscosity and the elastic components of dough visco-elasticity. In all the tests the extra dough-strength properties were evident for the variety (Guardian) that had the 5 + 10 glutenin subunits, in contrast to the other two with the 2 + 12 combination of subunits
Hamiltonian 2-forms in Kahler geometry, III Extremal metrics and stability
This paper concerns the explicit construction of extremal Kaehler metrics on
total spaces of projective bundles, which have been studied in many places. We
present a unified approach, motivated by the theory of hamiltonian 2-forms (as
introduced and studied in previous papers in the series) but this paper is
largely independent of that theory.
We obtain a characterization, on a large family of projective bundles, of
those `admissible' Kaehler classes (i.e., the ones compatible with the bundle
structure in a way we make precise) which contain an extremal Kaehler metric.
In many cases, such as on geometrically ruled surfaces, every Kaehler class is
admissible. In particular, our results complete the classification of extremal
Kaehler metrics on geometrically ruled surfaces, answering several
long-standing questions.
We also find that our characterization agrees with a notion of K-stability
for admissible Kaehler classes. Our examples and nonexistence results therefore
provide a fertile testing ground for the rapidly developing theory of stability
for projective varieties, and we discuss some of the ramifications. In
particular we obtain examples of projective varieties which are destabilized by
a non-algebraic degeneration.Comment: 40 pages, sequel to math.DG/0401320 and math.DG/0202280, but largely
self-contained; partially replaces and extends math.DG/050151
Biochemical parameters of silver catfish (Rhamdia quelen) after transport with eugenol or essential oil of Lippia alba added to the water
The transport of live fish is a routine practice in aquaculture and constitutes a considerable source of stress to the animals. The addition of anesthetic to the water used for fish transport can prevent or mitigate the deleterious effects of transport stress. This study investigated the effects of the addition of eugenol (EUG) (1.5 or 3.0 mu L L-1) and essential oil of Lippia alba (EOL) (10 or 20 mu L L-1) on metabolic parameters (glycogen, lactate and total protein levels) in liver and muscle, acetylcholinesterase activity (AChE) in muscle and brain, and the levels of protein carbonyl (PC), thiobarbituric acid reactive substances (TBARS) and nonprotein thiol groups (NPSH) and activity of glutathione-S-transferase in the liver of silver catfish (Rhamdia quelen; Quoy and Gaimard, 1824) transported for four hours in plastic bags (loading density of 169.2 g L-1). The addition of various concentrations of EUG (1.5 or 3.0 mu L L-1) and EOL (10 or 20 mu L L-1) to the transport water is advisable for the transportation of silver catfish, since both concentrations of these substances increased the levels of NPSH antioxidant and decreased the TBARS levels in the liver. In addition, the lower liver levels of glycogen and lactate in these groups and lower AChE activity in the brain (EOL 10 or 20 mu L L-1) compared to the control group indicate that the energetic metabolism and neurotransmission were lower after administration of anesthetics, contributing to the maintenance of homeostasis and sedation status.Fundacao de Amparo a Pesquisa do Estado do Rio Grande do Sul (FAPERGS/PRONEX) [10/0016-8]; Conselho Nacional de Pesquisa e Desenvolvimento Cientifico (CNPq) [470964/2009-0]; Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES); CNPqinfo:eu-repo/semantics/publishedVersio
An in vitro study to assess bioaccessibility and bioavailability of calcium from blue whiting (Micromesistius poutassou) fish bone powder
peer-reviewedThe aim of this study was to determine how well calcium-rich mineral extracts derived from blue whiting fish bone powders compare with existing calcium sources (commercially available fish bone supplement, calcium carbonate and milk powder) in terms of physicochemical properties, in vitro bioaccessibility and bioavailability using simulated gastrointestinal tract treatment and a Caco-2 cell culture model. Blue whiting calcium-rich fish bone powders (A to E) were supplied by Bio-marine Ingredients Ireland (BII) and a commercial calcium-rich fish bone powder was used as the positive control F. The BII calcium-rich fish bone powders analysed through atomic emission spectrometry were shown to have similar levels of mineral content in comparison with powder F. Solubility and rheology tests were performed on the rehydrated powders. The pH of BII calcium-rich fish bone powders in water solution (10% w/v) ranged from 6.96 to 9.09 compared to control F (pH 7.33). Following simulated oral, gastric and duodenal in vitro digestion using the COST INFOGEST standardised static adult digestion method, the fish powders A, E and F showed higher values of soluble ionic calcium than rehydrated milk powder. We compared in vitro bioavailability of the powders using the Caco-2 cell line to test the effects of calcium on human colonic epithelial cells, which confirmed that calcium from blue whiting fish bone was more bioavailable than calcium from milk and calcium carbonate. These data indicate that calcium-rich blue whiting fish bone powder compares well with existing calcium sources, in terms of physicochemical properties, bioaccessibility and bioavailability
Production and Decay of D_1(2420)^0 and D_2^*(2460)^0
We have investigated and final states and
observed the two established charmed mesons, the with mass
MeV/c and width MeV/c and
the with mass MeV/c and width
MeV/c. Properties of these final states, including
their decay angular distributions and spin-parity assignments, have been
studied. We identify these two mesons as the doublet predicted
by HQET. We also obtain constraints on {\footnotesize } as a function of the cosine of the relative phase of the two
amplitudes in the decay.Comment: 15 pages in REVTEX format. hardcopies with figures can be obtained by
sending mail to: [email protected]
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