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SeCOND-ORDeR TRANSIeNT STANDING WAVeS IN A ReCTANGULAR TANK

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Journal of Hydrodynamics 1995年第2期7卷 67-75页

作者： Wu G. X.(Department of Mechanical engineering ,Uniersity College London, Torrington Place,London WC1e 7je,U. K.) Univ of College London London United Kingdom

Analytical solution are derived based on the Fourier series for the three dimensional transient free surface problem in a rectangular tank. The analysis is based on the Stokes Perturbation and the second order result ... 详细信息

关键词： rectangular tank transient standing wave analytical solution

Conditional Independence Leads to Satisfaction of the Bell Inequality without Assuming Non-Locality or Non-Reality

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Advances in Pure Mathematics 2022年第5期12卷 405-417页

作者： Louis sica Institute for Quantum Studies Chapman University Orange USA Inspire Institute Inc. Alexandria USA

The original Bell inequality was obtained in a statistical derivation assuming three mutually cross-correlated random variables (four in the later version). Given that observations destroy the particles, the physical realization of three variables from an experiment producing two particles per trial requires two separate trial runs. One assumed variable value (for particle 1) occurs at a fixed instrument setting in both trial runs while a second variable (for particle 2) occurs at alternative instrument settings in the two trial runs. Given that measurements on the two particles occurring in each trial are themselves correlated, measurements from independent realizations at mutually exclusive settings on particle 2 are conditionally independent, i.e., conditionally dependent on particle 1, through probability. This situation is realized from variables defined by Bell using entangled particle pairs. Two correlations have the form that Bell computed from entanglement, but a third correlation from conditionally independent measurements has a different form. When the correlations are computed using quantum probabilities, the Bell inequality is satisfied without recourse to assumptions of non-locality, or non-reality.

关键词： Bell Theorem Bell Inequality entanglement Cross-Correlations Conditional Independence

Structure,stability,catalytic activity,and polarizabilities of small iridium clusters

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Chinese Physics B 2018年第6期27卷 225-230页

作者： Francisco e Jorge José R da Costa Venaancio Unidade Academica dc Ffsica Universidade Federal de Campina Grande 58429-900 Campina Grande Brazil Departamento de Ffsica Universidade Federal do Espfrito Santo 29060-900 Vitoria Brazil

At the second order Douglas–Kroll–Hess（DKH2） level, the B3 PW91 functional in conjunction with the relativistic all-electron basis set of valence triple zeta quality plus polarization functions are employed to compute bond lengths, dissociation energies, vertical ionization potentials, and the highest occupied molecular orbital-lowest unoccupied molecular orbital energy gaps of the small iridium clusters（Irn, n≤8）. These results are compared with the experimental and theoretical data available in the literature. Our results confirm the theoretical predictions made by Feng et al. about the catalytic activities of the Ir4 and Ir6 clusters. From the optimized geometries, DKH2 calculations of static electric mean dipole polarizabilities and polarizability anisotropies are also carried out. It is the first time that the polarizabilities of small iridium clusters have been studied. For n≤4, the mean dipole polarizabilities per atom present an odd–even oscillatory behavior,whereas from Ir5 to Ir8, they decrease with the cluster size increasing. The dependence of the polarizability anisotropy on the structure symmetry of the iridium cluster is verified.

关键词： B3PW91 functional all-electron basis sets DKH2 calculations iridium clusters polarizabilities

The nature of the companion of PSR J1719-1438: a white dwarf or an exotic object?

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Research in Astronomy and Astrophysics 2012年第7期12卷 813-816页

作者： J. e. Horvath Instituto de Astronomia Geofísica e Ciências Atmosfricas - Universidade de So Paulo

We raise the possibility that the very dense, compact companion of PSR J1719-1438, which has a Jupiter-like mass, is an exotic quark object rather than a light helium or carbon white dwarf. The exotic hypothesis naturally explains some of the observed features, and provides quite strong predictions for this system, to be confirmed or refuted in feasible future studies.

关键词： binary pulsars -- exotic matter-- pulsars: individual (PSR J1719-1438)

Numerical Study of the Injection of Carbon Dioxide in a Homogeneous Porous Media

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Open Journal of Fluid Dynamics 2018年第1期8卷 115-132页

作者： Luiz Umberto Rodrigues sica Independent Researcher Rio de Janeiro Brazil

This work proposes a locally conservative and less restrictive algorithm to solve the problem dealt with in [1], i.e. a two-phase flow in a homogeneous porous medium (water and CO2), with mass absorption between the fluid phases and reaction between the CO2 phase and the rock. The latter is modeled by two non-linear hyperbolic equations that represent the transport of the flowing phases for a given velocity field (equations of saturation and concentration). From the numerical point of view, we use the operator splitting technique to properly treat the time scale of each physical phenomenon and a high-order non-oscillatory central-scheme finite volume method for nonlinear hyperbolic equations proposed by [2] that was extended for a system of equations with source terms to treat the equations that govern the saturation and concentration of phases. In addition, with respect to source terms, the mass flux between fluid phases was handled using the flash methodology, whereas kinetic theory was applied for reproducing the changes in porosity and permeability that are caused by the reaction of CO2 with the rock. The same physical trends observed in [1] were obtained in our numerical results which indicate a good predictive capability. Furthermore, this method avoids the difficulties that arise when adopting small time steps enforced by CFL stability restrictions. Finally, the results obtained show that the applicability of the KT method is beyond just a single nonlinear conservation law with the absence of source terms.

关键词： Finite Volume Method Mass Absorption between Phases Flow in Porous Media Carbon Dioxide Sequestration

Bacterial microcosms obey Taylor’s law:effects of abiotic and biotic stress and genetics on mean and variance of population density

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ecological Processes 2012年第1期1卷 77-82页

作者： Oliver Kaltz Patricia escobar-Páramo Michael e Hochberg Joel e Cohen Institut des Sciences de l’evolution UMR CNRS-UM2-IRD5554CC 065UniversitéMontpellier 2Place Eugène BataillonMontpellier Cedex 0534095France Centro Internacional de Física(CIF) Biotechnology GroupUniversidad Nacional de ColombiaCra 30 N°45-03BogotáDCColombia Laboratory of Populations Rockefeller and Columbia Universities1230 York AvenueBox 20New YorkNY10065-6399USA

Introduction:According to the empirical regularity called Taylor’s law,the variance of population density in samples of populations is a power of the mean population *** exponent is often between 1 and *** experiments investigated how genetics,evolution,and environment shape Taylor’s ***:Genetically different strains(wild type and hypermutator)of the bacterium Pseudomonas fluorescens evolved and were assayed under different environmental conditions(with and without antibiotic rifampicin and bacteriophage SBW252,separately and in combination).Results:experimental treatments altered the exponent b,but not the power law form,of the relation between variance and mean population *** populations treated only with rifampicin had a narrow range of mean population densities and exponent b=*** exposed to rifampicin plus phage had b=*** ancestral,control,and phage-exposed populations,mean abundance varied widely and b was not significantly different from *** factors(mutation rate,selection)and ecological factors(abiotic,biotic)jointly influenced ***:Taylor’s power law relationship accurately and robustly described variance as a function of mean population density,with overall exponent b=*** and other experiments with different factors acting on bacterial population size support the relevance of models that predict‘universal’patterns of fluctuation scaling.

关键词： Taylor’s law Pseudomonas fluorescens rifampicin bacteriophage genetics

Point of Zero Salt effect: Relationships with Clay Mineralogy of Representative Soils of the So Paulo State, Brazil

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Pedosphere 2005年第5期15卷 545-553页

作者： M. e. ALVeS A. LAVOReNTI Departamento de Física e Informática Institute de Física de So Carlos-IFSC/USP So Carlos (SP) 13560-970(Brazil). Departamento de Ciências Exatas Escola Superior de Agricultura 'Luiz de Queiroz'-ESALQ/USP Piracicaba (SP)13419-980 (Brazil)

The point of zero salt effect （PZSe） is the soil pH value at which the magnitude of the variable surface charges is not changed due to variations in the ionic concentration of the soil solution. This property influences not only electrochemical phenomena occurring at the solid-solution interface but also the flocculation degree of the soil particles. In this study we investigated the relationships between the clay mineralogy and the PZSe values of representative soils of the Sāo Paulo State, Brazil. The results confirmed the usefulness of the difference between the soil pH values measured in 1 mol L^-1 KCl （pHKCl） and in water （pHH2O）（2 pHKCl-pHH2O） for estimating the PZSe of tropical soils, except for the ones rich in exchangeable Al; furthermore, the ApH index （pHKC1 - pHH2O） was highly correlated with the difference between the PZSe and pHH2O values, reiterating the △pH utility for estimating both the signal and the magnitude of the net surface charge of tropical soils. Finally, correlation and multiple regression analyses showed that the PZSe value of weathered non-allophanic tropical soils tends to increase and to equal the soil pH due to the weathering-induced kaolinite destabilization and concomitant Fe- and Al-oxide accumulation.

关键词： electrochemical properties iron oxides kaolinite tropical soils weathered soils

Stability analysis for time delay control of nonlinear systems in discrete-time domain with a standard discretisation method

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Control Theory and Technology 2020年第1期18卷 92-106页

作者： Jinoh Lee Gustavo A.MeDRANO-CeRDA je Hyung JUNG Advanced Robotics Istituto Italian.di TecnologiaVia Morego 30Genoa16163Italy Tecnalia Research and Innovation Mikeletegi Pasealekua1-3E-20009Donostia-San SebastianSpain

This paper provides stability analysis results for discretised time delay control(TDC)as implemented in a sampled data system with the standard form of zero-order *** first substantiate stability issues in discrete-time TDC using an example and propose sufficient stability criteria in the sense of *** parameters significantly affecting the overall system stability are the sampling period,the desired trajectory and the selection of the reference model dynamics.

关键词： Time delay control(TDC) discretisation stability analysis zero-order hold

The supernova remnant CTB 37B and its associated magnetar CXOU J171405.7-381031:evidence for a magnetar-driven remnant

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Research in Astronomy and Astrophysics 2011年第6期11卷 625-630页

作者： J.e.Horvath M.P.Allen Instituto de Astronomia Geofísica e Ciências Atmosféricas-Universidade de So PauloRua do Mato122605508-900 Cidade Universitria So Paulo SPBrazil CeFeT So Paulo Rua Pedro Vicente 62501109-010Caninde'So Paulo SPBrazil

We discuss the association between the candidate magnetar CXOU J171405.7-381031 and the supernova remnant CTB *** recent detection of the period derivative of the object allowed an estimation of a young characteristic age of only ～ *** value is too small to be compatible even with the minimum radius of the remnant being ≥ 10 pc,the value corresponding to the lower limit of the estimated distance of 10.2 ± 3.5 kpc,unless the true distance happens to be even smaller than the lower *** argue that a consistent scenario for the remnant＇s origin,in which the latter is powered by the energy injected by a young magnetar,is indeed more accurate to explain the young age,and demonstrates its non-standard（***-driven） nature.

关键词： stars:supernova — stars:neutron