distribution functions of background ions perturbed by the ion-acoustic solitons are calculated using the Sagdeev pseudopotential approach for the case of cold ions. Velocity and kinetic-energy distribution functions ...
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distribution functions of background ions perturbed by the ion-acoustic solitons are calculated using the Sagdeev pseudopotential approach for the case of cold ions. Velocity and kinetic-energy distribution functions are analyzed. Explicit expressions valid for the solitons of arbitrary amplitude are obtained. It is demonstrated that the solitons form a strongly nonequilibrium plasma in their vicinity. The results are compared with previous analytical calculations and results of simulations.
Based on the Cohen distribution function and physical spectrum concept, a new algorithm for numerical analysis of the time-frequency distribution of photon flux density of a chirped laser beam has been developed. This...
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We introduce Dirichlet Process Posterior Sampling (DPPS), a Bayesian non-parametric algorithm for multi-arm bandits based on Dirichlet Process (DP) priors. Like Thompson-sampling, DPPS is a probability-matching algori...
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Freshly injected interstellar Pickup Ions (PUIs)are expected to exhibit a simple, torus-shaped velocity distribution function. The PUIvelocity in the solar wind frame depends on the velocity of the interstellar neutra...
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Freshly injected interstellar Pickup Ions (PUIs)are expected to exhibit a simple, torus-shaped velocity distribution function. The PUIvelocity in the solar wind frame depends on the velocity of the interstellar neutral (ISN)population at the pick-up position. In this study, we aim to compare PUIvelocity distributions measured by the PLasma And SupraThermal Ion Composition (PLASTIC) instrument over the full orbit of Solar TErestrial RElations Observatory-Ahead (STEREO-A) directly. The STEREO-PLASTIC-A PUI observations are reanalysed wherein, instrumental effects of the limited Field Of View (FOV)are accounted for. We then define a new position-independent velocity measure for PUIsthat takes the local direction of the interstellar neutral inflow into account. The resulting new PUIvelocity measure corrects thereby for the position-dependent contribution of the ISNvelocity. Each position in the orbit of STEREO can be reached by ISNsfollowing one of two trajectories, which we call primary and secondary trajectories. Therein, ISNsfollowing the primary trajectory have a higher probability to reach the location before they are ionised than particles following the secondary trajectory. Our new PUIvelocity measure can be applied based on the assumption that all particles followed the primary trajectory or that all particles followed the secondary trajectory. Pitch-angle distributions are then analysed depending on the magnetic-field azimuthal angle for different orbital positions and different values of the PUIvelocity measure. The new velocity measure, ϖinj,p, shows an approximately constant cut-off over the complete orbit of STEREO-A. A torus signature is visible everywhere. Therein, a broadening of the torus signature outside the focusing cone and crescent regions and for lower ϖinj,p is observed. In addition, we illustrate the symmetry between the primary and secondary ISNtrajectory in the vicinity of the focusing cone. A torus signature associated with freshly injected P
In the phase diagram of a binary system one often encounters a compositional region in which two phases coexist. A common practice is to use the Lever Rule to describe the distributions of the two coexisting phases. H...
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In the phase diagram of a binary system one often encounters a compositional region in which two phases coexist. A common practice is to use the Lever Rule to describe the distributions of the two coexisting phases. However, if the binary system is a complete solid solution system, the Lever Rule cannot be used. A new type of distribution has been derived for a solid solution system without solubility gap. Application of the theory to pure and modified lead-zirconate-lead-titanate (PZT) systems shows excellent agreement with the experimental data. Several disputed facts about PZT are also explained satisfactorily.
We develop a biased Monte Carlo simulation technique to measure the distribution functions of the extension and the end-to-end distance of fluctuating filaments stretched by external force. The method is applicable fo...
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We develop a biased Monte Carlo simulation technique to measure the distribution functions of the extension and the end-to-end distance of fluctuating filaments stretched by external force. The method is applicable for arbitrary ratio of the persistence length to the contour length and for arbitrary forces, and also for the case of steric constraints, such as an external wall. The fundamental idea underlying the algorithm is to account explicitly for the length-scale dependence of the effective elastic moduli. We find that orientational fluctuations and wall effects produce non-Gaussian distributions for nearly rigid filaments in the small to intermediate force regime. The simulation results are tested against analytic expressions for the force-extension curves, both in the semiflexible and nearly stiff limits. (C) 2004 American Institute of Physics.
We derive analytical expressions for the one-point cumulative distribution function and probability density function of water saturation in the one-dimensional stochastic immiscible two-phase (Buckley-Leverett) proble...
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We derive analytical expressions for the one-point cumulative distribution function and probability density function of water saturation in the one-dimensional stochastic immiscible two-phase (Buckley-Leverett) problem. The sources of uncertainty are the spatial distributions of porosity and total velocity. The derived distribution functions involve integrals of the input random parameters. Comparisons with standard Monte Carlo simulation demonstrate that the method is applicable for input parameters with large variance and arbitrary correlation lengths. We also show that the proposed method is superior to the low-order statistical moment equations approach. We also outline a streamline-based strategy to extend our distribution-based method to multiple spatial dimensions.
Many proteins exhibit a sharp maximum in the heat capacity as a function of temperature as a result of the denaturation process. We have recently shown that the temperature dependence of the heat capacity can be conve...
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Many proteins exhibit a sharp maximum in the heat capacity as a function of temperature as a result of the denaturation process. We have recently shown that the temperature dependence of the heat capacity can be converted into a finite set of moments of the enthalpy distribution for the protein. Using the maximum-entropy method one can then use these moments to construct approximations to the enthalpy distribution function, the more moments used the better the approximation. We find that for many proteins the enthalpy distribution is bimodal when one expands the heat capacity in the neighborhood of the maximum in this function reflecting the presence of two distinctly different populations of molecules. In the present paper we analyze a soluble model system to test the accuracy of the approximate distribution functions obtained from the maximum-entropy method using a finite set of moments. For this purpose we pick the two-dimensional Ising model near the critical point, treating finite patches of lattice sites. In the finite system there is no true phase transition, but there is a sharp change in density and enthalpy in the neighborhood of the critical point. The distribution functions for the Ising model are in fact very similar to those for proteins. For the Ising model, we can then compare the exact distribution functions with those calculated using a finite number of moments and the maximum-entropy method and we find that the latter give excellent agreement with the exact results thus lending credibility to similar results obtained for distribution functions describing protein denaturation. (C) 2002 Elsevier Science B.V. All rights reserved.
Adsorption methods for determining the properties of stainless steel surface are presented. The relation between the actual and geometric surface is determined. The dependence of adsorption heat on the coverage logari...
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Adsorption methods for determining the properties of stainless steel surface are presented. The relation between the actual and geometric surface is determined. The dependence of adsorption heat on the coverage logarithm is derived from experimental adsorption isotherms for water at 298 K On the basis of this dependence, differential and integral distribution functions of adsorption sites by adsorption heat is calculated. It is shown that in the case of water adsorption on the surface of stainless steel at 298 K, adsorption heat for 90% of adsorption sites ranges from 4.4 x 10(7) to 7.9 x 10(7) J/kmol. (C) 2017 Elsevier Ltd. All rights reserved.
The problem of describing the distribution functions of tsunami wave heights is discussed. Data on runup heights obtained in field surveys of several tsunamis for the last decade are used to calculate the empirical di...
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The problem of describing the distribution functions of tsunami wave heights is discussed. Data on runup heights obtained in field surveys of several tsunamis for the last decade are used to calculate the empirical distribution functions. It is shown that the log-normal distribution describes the observed data well. This means that the irregular topography and coastline are major factors which influence the height distribution. The power distribution related with the geometric decay of the propagated wave is a good approximation for one event (Sulawesi, January 1, 1996) only. Results of a numerical simulation of the tsunami event in the Japan (East) Sea on July 12, 1993 are presented. It is shown that the computed wave height distribution, obtained by using the runup correction in the framework of nonlinear shallow-water theory, is in good agreement with the observed height distribution. Simulations are used to study the transformation of the distribution function on different distances from the source.
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