414 research outputs found
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Wavelet approach to accelerator problems. 3: Melnikov functions and symplectic topology
This is the third part of a series of talks in which the authors present applications of methods of wavelet analysis to polynomial approximations for a number of accelerator physics problems. They consider the generalization of the variational wavelet approach to nonlinear polynomial problems to the case of Hamiltonian systems for which they need to preserve underlying symplectic or Poissonian or quasicomplex structures in any type of calculations. They use the approach for the problem of explicit calculations of Arnold-Weinstein curves via Floer variational approach from symplectic topology. The loop solutions are parameterized by the solutions of reduced algebraical problem--matrix Quadratic Mirror Filters equations. Also they consider wavelet approach to the calculations of Melnikov functions in the theory of homoclinic chaos in perturbed Hamiltonian systems
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Wavelet approach to accelerator problems. 1: Polynomial dynamics
This is the first part of a series of talks in which the authors present applications of methods from wavelet analysis to polynomial approximations for a number of accelerator physics problems. In the general case they have the solution as a multiresolution expansion in the base of compactly supported wavelet basis. The solution is parameterized by solutions of two reduced algebraical problems, one is nonlinear and the second is some linear problem, which is obtained from one of the next wavelet constructions: Fast Wavelet Transform, Stationary Subdivision Schemes, the method of Connection Coefficients. In this paper the authors consider the problem of calculation of orbital motion in storage rings. The key point in the solution of this problem is the use of the methods of wavelet analysis, relatively novel set of mathematical methods, which gives one a possibility to work with well-localized bases in functional spaces and with the general type of operators (including pseudodifferential) in such bases
Effects of nanodispersed iron on the morphofunctional parameters of the blood system
The effects of nanodispersed iron forms on the morphology and function of the blood system were studied. Maghemite and lepidocrocite caused a leukocytic shift towards segmented neutrophil forms, reduction of lymphocyte rigidity, and stimulated their compactization. In addition, the counts of small hyperchromatic erythrocytes with high rigidity increased in the blood flow. The results indicated that a single dose of nanodispersed iron-containing drugs improved the blood respiratory function and its microrheolog
Measurement of the Flux of Ultrahigh Energy Cosmic Rays from Monocular Observations by the High Resolution Fly's Eye Experiment
We have measured the cosmic ray spectrum above 10^17.2 eV using the two air
fluorescence detectors of the High Resolution Fly's Eye observatory operating
in monocular mode. We describe the detector, photo-tube and atmospheric
calibrations, as well as the analysis techniques for the two detectors. We fit
the spectrum to a model consisting of galactic and extra-galactic sources.Comment: 4 pages, 4 figures. Uses 10pt.rtx, amsmath.sty, aps.rtx, revsymb.sty,
revtex4.cl
Search for Point Sources of Ultra-High Energy Cosmic Rays Above 40 EeV Using a Maximum Likelihood Ratio Test
We present the results of a search for cosmic ray point sources at energies
above 40 EeV in the combined data sets recorded by the AGASA and HiRes stereo
experiments. The analysis is based on a maximum likelihood ratio test using the
probability density function for each event rather than requiring an a priori
choice of a fixed angular bin size. No statistically significant clustering of
events consistent with a point source is found.Comment: 7 pages, 7 figures. Accepted for publication in The Astrophysical
Journa
Highly Porous Carbon Materials Filled with Nickel Hydroxide Nanoparticles; Synthesis, Study, Application in Electrochemistry
Nickel hydroxide was deposited on the surface of the porous carbon to obtain a cathode material for supercapacitors. This work is the first part of the study of Ni(OH)2/С composite, which considers the conditions of its synthesis using two types of porous carbon matrices with a highly developed specific surface area (1000–3000 m2/g) and two types of precursors (NiCl2*6H2O and Ni(N3)2). The morphology of the systems, in particular the shape and size characteristics of the hydroxide filler particles, was examined using the scanning electron microscopy, X-ray diffraction, and nitrogen adsorption-desorption at 77 K. The measurements of capacity of the Ni(OH)2/С-electrodes were made in 6 M KOH using an asymmetric two-electrode cell (a porous carbon material with known electrode characteristics was employed as the counter electrode). The capacity was shown to decrease by 22–56% with increasing the scanning rate from 10 to 80 mV/s. A maximum capacity of the composite was obtained at a scanning rate of 10 mV/s was 346 F/g
Lipid Peroxidation in the Pre-Reactive Period of Cold Injury
Pathological processes in the pre-reactive period of cold injury have not been studied.The purpose of this study is to assess the morphological and biochemical parameters of blood in the body of patients in the pre-reactive period of cold injury.Material and methods. We examined patients with cold injury in the pre-reactive period. Determined: diene conjugates, malonic dialdehyde, the total content of low molecular weight antioxidants, superoxide dismutase activity, catalase,glutathione peroxidase, glutathione reductase, using a SPECORD 40 spectrophotometer. The serum biochemical parameters in the serum were determined by biochemical automator analysis. Statistical processing of the data was performed using IBM SPSS Statistics 19.Results and discussion. Features of the biochemical profile of blood in the pre-reactive period of cold injury in the human body are an increase in concentration of glucose and triacylglycerides in blood, an increase in transaminase activity, as aresult of inflammatory and destructive processes, a decrease in the cholesterol concentration in the blood of patients. At the same time, the pre-reactive period of cold injury is characterized by an increase in monocytes compared with the control, which, in combination with hypoxia, leads to an intensification of lipid peroxidation processes. In addition, the antioxidant protection in the pre-reactive period in the body of patients increased slightly.Conclusion. According to the results of our research, already at the stage of the pre-reactive period of cold injury there is a significant intensification of free radical lipid oxidation processes
An upper limit on the electron-neutrino flux from the HiRes detector
Air-fluorescence detectors such as the High Resolution Fly's Eye (HiRes)
detector are very sensitive to upward-going, Earth-skimming ultrahigh energy
electron-neutrino-induced showers. This is due to the relatively large
interaction cross sections of these high-energy neutrinos and to the
Landau-Pomeranchuk-Migdal (LPM) effect. The LPM effect causes a significant
decrease in the cross sections for bremsstrahlung and pair production, allowing
charged-current electron-neutrino-induced showers occurring deep in the Earth's
crust to be detectable as they exit the Earth into the atmosphere. A search for
upward-going neutrino-induced showers in the HiRes-II monocular dataset has
yielded a null result. From an LPM calculation of the energy spectrum of
charged particles as a function of primary energy and depth for
electron-induced showers in rock, we calculate the shape of the resulting
profile of these showers in air. We describe a full detector Monte Carlo
simulation to determine the detector response to upward-going
electron-neutrino-induced cascades and present an upper limit on the flux of
electron-neutrinos.Comment: 13 pages, 3 figures. submitted to Astrophysical Journa
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