1,095 research outputs found
The classification of all single travelling wave solutions to Calogero-Degasperis-Focas equation
Under the travelling wave transformation, Calogero-Degasperis-Focas equation
was reduced to an ordinary differential equation. Using a symmetry group of
one-parameter, this ODE was reduced to a second order linear inhomogeneous ODE.
Furthermore, we applied the change of the variable and complete discrimination
system for polynomial to solve the corresponding integrals and obtained the
classification of all single travelling wave solutions to
Calogero-Degasperis-Focas equation.Comment: 9 page
Solving Inverse Conductivity Problems In Doubly Connected Domains By the Homogenization Functions of Two Parameters
In the paper, we make the first attempt to derive a family of two-parameter homogenization functions in the doubly connected domain, which is then applied as the bases of trial solutions for the inverse conductivity problems. The expansion coefficients are obtained by imposing an extra boundary condition on the inner boundary, which results in a linear system for the interpolation of the solution in a weighted Sobolev space. Then, we retrieve the spatial- or temperature-dependent conductivity function by solving a linear system, which is obtained from the collocation method applied to the nonlinear elliptic equation after inserting the solution. Although the required data are quite economical, very accurate solutions of the space-dependent and temperature-dependent conductivity functions, the Robin coefficient function and also the source function are available. It is significant that the nonlinear inverse problems can be solved directly without iterations and solving nonlinear equations. The proposed method can achieve accurate results with high efficiency even for large noise being imposed on the input data
Mössbauer study of nanodimensional nickel ferrite-mechanochemical synthesis and catalytic properties
Iron-nickel spinel oxide NiFe2O4 nanoparticles have been prepared by the combination of chemical precipitation and subsequent mechanical milling. For comparison, their analogue obtained by thermal synthesis is also studied. Phase composition and structural properties of iron-nickel oxides are investigated by X-ray diffraction and Mössbauer spectroscopy. Their catalytic behavior in methanol decomposition to CO and methane is tested. An influence of the preparation method on the reduction and catalytic properties of iron-nickel samples is established
Large Kinetic Power in FRII Radio Jets
We investigate the total kinetic powers (L_{j}) and ages (t_{age}) of
powerful jets of four FR II radio sources (Cygnus A, 3C 223, 3C 284, and 3C
219) by the detail comparison of the dynamical model of expanding cocoons with
observed ones. It is found that these sources have quite large kinetic powers
with the ratio of L_{j} to the Eddington luminosity (L_{Edd}) resides in . Reflecting the large kinetic powers, we also find that the
total energy stored in the cocoon (E_{c}) exceed the energy derived from the
minimum energy condition (E_{min}): . This implies that
a large amount of kinetic power is carried by invisible components such as
thermal leptons (electron and positron) and/or protons.Comment: 5 pages, accepted for publication in Astrophysics and Space Scienc
Mass and number size distributions of particulate matter components : comparison of an industrial site and an urban background site
AbstractSize-resolved composition of particulate matter (PM) sampled in the industrial town of Port Talbot (PT), UK was determined in comparison to a typical urban background site in Birmingham (EROS). A Micro-Orifice Uniform Deposit Impactor (MOUDI) sampler was deployed for two separate sampling campaigns with the addition of a Grimm optical spectrometer at the PT site. MOUDI samples were analysed for water-soluble anions (Cl−, NO3− and SO42−) and cations (Na+, NH4+, K+, Mg2+ and Ca2+) and trace metals (Al, V, Cr, Mn, Fe, Cu, Zn, Sb, Ba and Pb). The PM mass distribution showed a predominance of fine particle (PM2.5) mass at EROS whereas the PT samples were dominated by the coarse fraction (PM2.5-10). SO42−, Cl−, NH4+, Na+, NO3−, and Ca2+ were the predominant ionic species at both sites while Al and Fe were the metals with highest concentrations at both sites. Mean concentrations of Cl−, Na+, K+, Ca2+, Mg2+, Cr, Mn, Fe and Zn were higher at PT than EROS due to industrial and marine influences. The contribution of regional pollution by sulphate, ammonium and nitrate was greater at EROS relative to PT. The traffic signatures of Cu, Sb, Ba and Pb were particularly prominent at EROS. Overall, PM at EROS was dominated by secondary aerosol and traffic-related particles while PT was heavily influenced by industrial activities and marine aerosol. Profound influences of wind direction are seen in the 72-hour data, especially in relation to the PT local sources. Measurements of particle number in 14 separate size bins plotted as a function of wind direction and speed are highly indicative of contributing sources, with local traffic dominant below 0.5μm, steelworks emissions from 0.5 to 15μm, and marine aerosol above 15μm
Moyal Representation of the String Field Star Product in the Presence of a B-background
In this paper we show that in the presence of an anti-symmetric tensor
-background, Witten's star algebra for open string fields persists to
possess the structure of a direct product of commuting Moyal pairs. The
interplay between the noncommutativity due to three-string overlap and that due
to the -background is our main concern. In each pair of noncommutative
directions parallel to the -background, the Moyal pairs mix string modes in
the two directions and are labeled, in addition to a continuous parameter, by
{\it two} discrete values as well. However, the Moyal parameters are
-dependent only for discrete pairs. We have also demonstrated the large-
contraction of the star algebra, with one of the discrete Moyal pairs dropping
out while the other giving rise to the center-of-mass noncommutative function
algebra.Comment: minor notation chang
A scheme with two large extra dimensions confronted with neutrino physics
We investigate a particle physics model in a six-dimensional spacetime, where
two extra dimensions form a torus. Particles with Standard Model charges are
confined by interactions with a scalar field to four four-dimensional branes,
two vortices accommodating ordinary type fermions and two antivortices
accommodating mirror fermions. We investigate the phenomenological implications
of this multibrane structure by confronting the model with neutrino physics
data.Comment: LATEX, 24 pages, 9 figures, minor changes in the tex
Prognostic value of symptom burden for overall survival in patients receiving chemotherapy for advanced nonsmall cell lung cancer
BACKGROUND: Patient-reported outcomes have shown independent prognostic value for patients with nonsmall cell lung cancer (NSCLC). However, translating patient-reported outcomes into useful prognostic information for individual patients has been problematic. METHODS: A total of 94 patients with advanced NSCLC and an Eastern Cooperative Oncology Group performance status (PS) of 0 to 2 who qualified for chemotherapy rated symptom severity using the M. D. Anderson Symptom Inventory before and after their first chemotherapy cycle. Prognostic values of baseline symptoms and changes in symptom severity were examined by Cox proportional hazards models. RESULTS: In multivariate analysis, controlled for demographic and other factors, baseline coughing rated ≤4 independently predicted significantly higher risk for shorter survival (hazards ratio [HR], 8.69; P < .0001). Patients with coughing ≤4 and a PS of 2 were more likely to have shorter survival (HR, 20.6; P < .0001) than patients with coughing <4 and a PS of 0 to 1. A 1-point or greater increase in severity of fatigue (P < .05), shortness of breath, or poor appetite (P < .01) from baseline to the end of the first chemotherapy cycle was also found to be independently associated with higher risk for poor survival. CONCLUSIONS: An increased risk for shorter survival was indicated by moderate to severe coughing at baseline or by increased fatigue or shortness of breath during the first chemotherapy cycle in patients with advanced NSCLC. Although cross-validation is needed, these data suggest that an individual patient's symptom severity scores, quickly obtainable in the clinic, might contribute clinically useful information for treatment planning for that patient
Pair production of the heavy leptons in future high energy linear e^{+}e^{-} colliders
The littlest Higgs model with T-parity predicts the existence of the T-odd
particles, which can only be produced in pair. We consider pair production of
the T-odd leptons in future high energy linear collider ().
Our numerical results show that, as long as the T-odd leptons are not too
heavy, they can be copiously produced and their possible signals might be
detected via the processes in future
experiments.Comment: Discussions added, typos and references correcte
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