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Saturation spectroscopy of vibronic transitions in single molecules

CHEMICAL PHYSICS LETTERS 2002年第5-6期357卷 397-402页

作者： Plakhotnik, T Nonn, T Palm, V ETH Zentrum Swiss Fed Inst Technol Chem Phys Lab CH-8092 Zurich Switzerland

A novel technique of saturation spectroscopy is applied to study the individual vibronic spectra of single impurity molecules embedded in a low-temperature solid matrix, Homogeneous linewidths and vibrational frequencies for two lower vibronic levels of the excited electronic state S-1 are determined for several terrylene single molecules in a naphthalene crystal, which indicates a noticeable distribution of these parameters. A certain correlation can be pointed out between vibrational frequency and a purely electronic transition frequency of a terrylene molecule. (C) 2002 Elsevier Science B.V. All rights reserved.

关键词： Vibrational frequencies Spectrography vibronic Vibronic level molecules single molecule Saturated distributed parameter Vibronic spectra Vibronic transition Excited electronic state

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A series of proton flares in July 1985 from observations by the Prognoz-10 satellite and Vega-1, 2 spacecraft

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COSMIC RESEARCH 2003年第1期41卷 19-27页

作者： Lyubimov, GP Tulupov, VI Moscow MV Lomonosov State Univ Skobeltsyn Inst Nucl Phys Moscow 119899 Russia

The enhancements of solar protons with an energy of more than 30 MeV, originating from flares in one active region and observed simultaneously aboard three spacecraft Vega-1, 2 and Prognoz-10 in July 1985, are analyzed and approximated in this work by using the reflection model [2]. The numerical values of several physical parameters (the parameters of distribution of solar cosmic ray (SCR) particles inside heliosphere traps, the coefficients of trap transparency) that are not observed by direct measurements are estimated.

关键词： DIRECT METERING hydrogen ions solar protons Spacecraft distress signal satellites distributed parameter Heliosphere

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Stabilization of the multi-asset Black-Scholes PDE using differential flatness theory

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IFAC-PapersOnLine 2016年第8期49卷 180-185页

作者： Rigatos, Gerasimos Siano, Pierluigi Unit of Industrial Automation Industrial Systems Institute Rion Patras 26504 Greece Department of Industrial Engineering University of Salerno Fisciano84084 Italy

A method for feedbsck control of the multi-asset Black-Scholes PDE is developed. By applying semi-discretization and a finite differences scheme the multi-asset Black-Scholes PDE is transformed into a state-space model consisting of ordinary nonlinear differential equations. For this set of differential equations it is shown that differential flatness properties hold. This enables to solve the associated control problem and to succeed stabilization of the options’ dynamics. For the local subsystems, into which the multi-asset Black-Scholes PDE is decomposed, it becomes possible to apply boundary-based feedback control. For each subsystem which is related to a nonlinear ODE, a virtual control input is computed, that can invert the subsystem's dynamics and can eliminate the subsystem's tracking error. From the last row of the state-space description, the control input (boundary condition) that is actually applied to the multi-asset Black-Scholes PDE system is found. The stability of the proposed control scheme is confirmed with the use of the Lyapunov method. © 2016

关键词： Nonlinear equations Boundary conditions Feedback control Lyapunov methods Nonlinear feedback Ordinary differential equations Stabilization State space methods Black Scholes PDE Differential flatness Differential flatness theories differential flatnss theory distributed parameter Nonlinear differential equation State space models State space description

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Numerical Solution of a Zonal Feedback Control Problem for the Heating Process

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IFAC-PapersOnLine 2018年第30期51卷 251-256页

作者： Guliyev, Samir Z. Institute of Control Systems of ANAS Azerbaijan Baku Azerbaijan State Oil and Industrial University Baku Azerbaijan

We consider a feedback control problem for an object with distributed parameters using continuous observation of the object's phase state at its particular points, by the example of controlling the process of heating a tubular heat exchanger in a steam jacket. To solve the feedback control problem, we propose to use first order numerical methods. To this purpose we derive formulas for the components of the gradient of the objective functional in the space of optimized parameters. We have developed the corresponding software, on the basis of which numerous numerical experiments were carried out. © 2016

关键词： Process control Feedback control Heat exchangers Numerical methods Continuous observation distributed parameter distributed systems Feedback control problem Heating process Numerical experiments Tubular heat exchangers Zonal control

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MATHEMATICAL-MODELING OF 3-PHASE ELECTRODE SALT-BATH FURNACE WITH THE TWO-DIMENSIONAL ELECTRIC-FIELD

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ARCHIV FUR ELEKTROTECHNIK 1988年第1期71卷 19-25页

作者： JANDA, S KALIC, D Tehnicki fakultet

After a short historical survey of the attempts to solve the problem of designing and determining the dimensions of a three-phase electrode salt-bath furnace, the authors apply the theory of the three-phase transmission line with uniformly distributed parameters to the phenomena in the electrode furnace. Taking all necessary boundary conditions and permissible simplifications, formulae for most widely sprcad types of the furnaces are derived, which allow the calculation of input admittance and input power of the furnace, as well as other important electric quantities.

关键词： mathematical modeling input admittance Electrodes Furnaces Electric fields Boundary conditions distributed parameter PHENOMENON

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Natural selection associated with color vision defects in some population groups of Eurasia

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RUSSIAN JOURNAL OF GENETICS 2014年第1期50卷 71-81页

作者： Evsyukov, A. N. Russian Acad Sci Vavilov Inst Gen Genet Moscow 119991 Russia

Fitness coefficients and other quantitative parameters of selection associated with the generalized color blindness gene CB+ were obtained for three ethnogeographic population groups, including Belarusians from Belarus, ethnic populations of the Volga-Ural region, and ethnic populations of Siberia and the Far East of Russia. All abnormalities encoded by the OPN1LW and OPN1MW loci were treated as deviations from normal color perception. Coefficients were estimated from an approximation of the observed CB+ frequency distributions to the theoretical stationary distribution for the Wright island model. This model takes into account the pressure of migrations, selection, and random genetic drift, while the selection parameters are represented in the form of the distribution parameters. In the populations of Siberia and Far East, directional selection in favor of normal color vision and the corresponding allele CB- was observed. In the Belarusian and ethnic populations of the Volga-Ural region, stabilizing selection was observed. The selection intensity constituted 0.03 in the Belarusian;0.22 in the ethnic populations of the Volga-Ural region;and 0.24 in ethnic populations of Siberia and Far East.

关键词： distribution migrations parameters natural selection selection intensity Far East Population Groups Color Vision Defects Siberia Eurasia normal color distributed parameter OPN1LW gene

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Hardware and Software Methods for Restoring Input Signals of Dynamic Systems with distributed parameters. Reduction to the Perfect Device

Hardware and Software Methods for Restoring Input Signals of...

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International Conference on Complex Systems: Control and Modeling Problems

作者： Ilia Boikov Nikolay Krivulin Penza State University PenzaRussia

ISBN: (纸本)9781728167015

The paper presents a brief review of the authors' results on methods for reconstructing input signals of dynamic systems. Continuous and discrete systems with distributed and lumped parameters are considered. Mathematical models of these systems are differential and difference equations, as well as integral equations. The main focus of the work is on methods for reconstructing input signals based on the results of preliminary parametric identification of systems. In this regard, a separate section is devoted to the authors' results review on the methods of parametric identification of dynamic systems. Methods for the precise determination of the impulse response functions of continuous and discrete stationary systems using two input signals are considered. A number of approximate methods are presented. Methods of parameters identification and restoration of input signals in systems modeled by Volterra series are investigated. A separate section is devoted to the results application in thing of specific technical systems.

关键词： approximation theory differential equations discrete systems integral equations parameter estimation signal restoration Volterra series Discrete systems Volterra series Signal restoration Dynamic systems Integral equations Approximation Theory IMPULSE RESPONSE parameter estimation Differential equations Computer hardware signals DIFFERENTIAL-DIFFERENCE EQUATIONS input signal distributed parameter

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MAXIMUM-LIKELIHOOD-ESTIMATION OF K-DISTRIBUTION parameterS FOR SAR DATA

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IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 1993年第5期31卷 989-999页

作者： JOUGHIN, IR PERCIVAL, DB WINEBRENNER, DP Applied Physics Laboratory University of Washington Seattle WA USA

The K distribution has proven to be a promising and useful model for backscattering statistics in synthetic aperture radar (SAR) imagery. However, most studies to date have relied on a method of moments technique involving second and fourth moments to estimate the parameters of the Ii distribution. The variance of these parameter estimates is large in cases where the sample size is small and/or the true distribution of backscattered amplitude is highly non-Rayleigh. In this paper, we apply a maximum likelihood estimation method directly to the K distribution. We consider the situation for single look SAR data as well as a simplified model for multilook data. We investigate the accuracy and uncertainties in maximum likelihood parameter estimates as functions of sample size and the parameters themselves. We find improved results compared with those obtained by the method of moments for sample sizes of 1000 or less. We also compare our results with those from a new method given by Raghavan and from a nonstandard method of moments technique;maximum likelihood parameter estimates prove to be at least as accurate as those from the other estimators in all cases tested, and are more accurate in most cases. Finally, we compare the simplified multilook model with nominally four-look SAR data acquired by the Jet Propulsion Laboratory AIRSAR over sea ice in the Beaufort Sea during March 1988. We find that the model fits data from both first-year and multiyear ice well and that backscattering statistics from each ice type are moderately non Rayleigh. We note that the distributions for our data set differ too little between ice types to allow discrimination based on differing distribution parameters.

关键词： Ice Types Synthetic aperture radar Beaufort Sea METHOD OF MOMENTS maximum likelihood estimation K-distribution Specific absorption rate Sample Size distributed parameter Rescue maximum likelihood

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Bayesian optimum designs for discriminating between models with any distribution

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COMPUTATIONAL STATISTICS & DATA ANALYSIS 2010年第1期54卷 143-150页

作者： Tommasi, C. Lopez-Fidalgo, J. Univ Milan Dept Econ Business & Stat I-20122 Milan Italy Univ Castilla La Mancha Dept Math E-13071 Ciudad Real Spain

The Bayesian KL-optimality criterion is useful for discriminating between any two statistical models in the presence of prior information. If the rival models are not nested then, depending on which model is true, two different Kullback-Leibler distances may be defined. The Bayesian KL-optimality criterion is a convex combination of the expected values of these two possible Kullback-Leibler distances between the competing models. These expectations are taken over the prior distributions of the parameters and the weights of the convex combination are given by the prior probabilities of the models. Concavity of the Bayesian KL-optimality criterion is proved, thus classical results of Optimal Design Theory can be applied. A standardized version of the proposed criterion is also given in order to take into account possible different magnitudes of the two Kullback-Leibler distances. Some illustrative examples are provided. (C) 2009 Elsevier B.V. All rights reserved.

关键词： discriminating between distribution Kullback-Leibler Convexity Bayesian inference distributed parameter Optimal design

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Electron transport: Multiple and plural elastic scattering

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NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS 1996年第1-2期108卷 23-34页

作者： Kawrakow, I Clinic for Radiation Therapy and Oncology Radiological Center Leipzig University Liebigstr. 20a 04103 Leipzig Germany

We present a new approach to small angle multiple and plural scattering of electrons applicable for all step sizes in atomic and compound matter Using the screened Rutherford law to describe single scattering and the momentum transfer as the ''angular'' variable, a simple analytical expression for the multiple scattering distribution is found. The parameters of this distribution are fixed by a chi(2)-fit to the distribution calculated by the Monte Carlo technique. The validity of the small angle approximation is investigated. It is found, that at very large step sizes, the multiple scattering distribution becomes a Gaussian. The new approach is implemented in the EGS4 code system and tested in a variety of geometries. It is found, that the new multiple scattering subroutine is 2-3 times faster as the standard EGS4 one.

关键词： Momentum transfer single scattering Scattering multiples step size Angle subroutine Atomicity Monte Carlo technique broadcasting Small angle approximation distributed parameter

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