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A fully recursive approach to the computation of higher order sensitivities of linear active circuits

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS I-FUNDAMENTAL THEORY AND APPLICATIONS 1999年第8期46卷 907-919页

作者： Vallette, F Vasilescu, G Alquié, G Univ Paris 06 F-75252 Paris 05 France

This paper presents a new recursive method to compute the higher order sensitivities of any node voltage, as well as of the circuit performances (gain, input/output impedance, or reflection coefficients) with respect to all circuit parameters, The starting point is the adjoint system approach and the expressions obtained for the first-order sensitivities when using nodal analysis. Instead of further differentiating them, the images of the higher order derivatives are generated by recursion up to any given order. The procedure is illustrated with three examples.

关键词： Circuit optimization recursion method recursion Recursive Active circuits antimicrobial susceptibility circuit parameter higher-order

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SIMULATION OF MULTIPATH IMPULSE-RESPONSE FOR INDOOR WIRELESS OPTICAL CHANNELS

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 1993年第3期11卷 367-379页

作者： BARRY, JR KAHN, JM KRAUSE, WJ LEE, EA MESSERSCHMITT, DG UNIV CALIF BERKELEY DEPT EECS BERKELEY CA 94720 USA

We present a recursive method for evaluating the impulse response of an indoor free-space optical channel with Lambertian reflectors. The method, which accounts for multiple reflections of any order, enables accurate analysis of the effects of multipath dispersion on high-speed indoor optical communication systems. We present a simple algorithm for computer implementation of the technique. We present computer simulation results for both line-of-sight and diffuse transmitter configurations. In both cases, we find that reflections of multiple order are a significant source of intersymbol interference. We also report experimental measurements of optical multipath, which help verify the accuracy of our simulations.

关键词： INDOORS recursion method OPTICAL CHANNEL simulating wireless multiple reflections IMPULSE RESPONSE Reflection intersymbolic interference

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An estimation method for the semiparametric mixed effects model

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BIOMETRICS 1999年第1期55卷 102-110页

作者： Tao, NG Palta, M Yandell, BS Newton, MA Univ Wisconsin Dept Stat Madison WI 53706 USA Univ Wisconsin Dept Prevent Med Madison WI 53705 USA Univ Wisconsin Dept Biostat Madison WI 53792 USA

A semiparametric mixed effects regression model is proposed for the analysis of clustered or longitudinal data with continuous, ordinal, or binary outcome. The common assumption of Gaussian random effects is relaxed by using a predictive recursion method (Newton and Zhang, 1999) to provide a nonparametric smooth density estimate. A new strategy is introduced to accelerate the algorithm, Parameter estimates are obtained by maximizing the marginal profile likelihood by Powell's conjugate direction search method. Monte Carlo results are presented to show that the method can improve the mean squared error of the fixed effects estimators when the random effects distribution is not Gaussian. The usefulness of visualizing the random effects density itself is illustrated in the analysis of data from the Wisconsin Sleep Survey. The proposed estimation procedure is computationally feasible for quite large data sets.

关键词： generalized linear models longitudinal data mixture model recursion method random effects semiparametric mixed effects model

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Dynamic phase transition in the kinetic spin-3/2 Blume-Emery-Griffiths model in an oscillating field

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JOURNAL OF PHYSICS-CONDENSED MATTER 2006年第29期18卷 6635-6653页

作者： Canko, Osman Deviren, Bayram Keskin, Mustafa Erciyes Univ Dept Phys TR-38039 Kayseri Turkey

The dynamic phase transitions are studied, within a mean-field approach, in the kinetic Blume-Emery-Griffiths model under the presence of a time varying ( sinusoidal) magnetic field by using the Glauber-type stochastic dynamics. The behaviour of the time-dependence of the order parameters and the behaviour of the average order parameters in a period, which is also called the dynamic order parameters, as a function of reduced temperature, are investigated. The nature ( continuous and discontinuous) of transition is characterized by studying the average order parameters in a period. The dynamic phase transition points are obtained and the phase diagrams are presented in the reduced magnetic field amplitude and reduced temperature plane. The phase diagrams exhibit one, two, or three dynamic tricritical points and a dynamic double critical end point, and besides a disordered and two ordered phases, seven coexistence phase regions exist, which strongly depend on interaction parameters. We also calculate the Liapunov exponent to verify the stability of solutions and the dynamic phase transition points.

关键词： CAPEL MODEL ISING-MODEL recursion method MULTICRITICAL BEHAVIOR HYSTERESIS LOOPS SQUARE LATTICE BEG MODEL DIAGRAMS SYSTEMS SUSCEPTIBILITY

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Theoretical evidence of a significant modification of the electronic structure of double-walled carbon nanotubes due to the interlayer interaction

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CARBON 2020年 170卷 30-36页

作者： Popov, Valentin N. Univ Sofia Fac Phys BG-1164 Sofia Bulgaria

The recently reported experimental optical spectra of double-walled carbon nanotubes exhibit more peaks than it could be expected based on the layers alone. The appearance of excess peaks has been attributed to the interlayer interaction. In order to elucidate the origin of the excess peaks, we perform calculations of the optical absorption of a particular nanotube using the recursion method with non-orthogonal tight-binding basis functions. Our study shows that the interlayer interaction can give rise to major changes in the electronic structure of this nanotube, manifesting themselves with shifts of the optical transitions and appearance of new optical transitions. The derived absorption spectrum is found to be in excellent agreement with the available experimental data, which justifies the use of the proposed approach for double-walled carbon nanotubes. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Double-walled carbon nanotubes Density of states Optical absorption recursion method

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Nonparametric density estimation of streaming data using orthogonal series

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COMPUTATIONAL STATISTICS & DATA ANALYSIS 2009年第12期53卷 3980-3986页

作者： Caudle, Kyle A. Wegman, Edward George Mason Univ Dept Computat & Data Sci Fairfax VA 22030 USA USN Acad Dept Math Annapolis MD 21402 USA

Streaming data represent a serious challenge because implicit in the nature of streaming data, data are not exchangeable and are not storable. This means data must be processed on the fly. Density estimation is an essential tool used to make sense of data collected by large scale systems. In this paper, we present a recursive method for constructing and updating an estimate of the nonstationary probability density function. Our approach is shown to work well with simulated data as well as with real data. (C) 2009 Elsevier B.V. All rights reserved.

关键词： challenge approach estimation Implicit observational data recursion method large-scale systems simulated data Kernel Density Estimation orthogonal series Streaming

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Study on Modification Mechanism of Rare Earth in ZA27 Cast Alloy with Electronic Theory and Molecular Dynamics method

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Journal of Materials Science & Technology 2004年第5期20卷 586-588页

作者： Guili LIU, Rongde LI and Zhenping ZHOUSchool of Materials Science and Engineering, Shenyang University of Technology, Shenyang 110023, China Sch. of Mat. Sci. and Eng. Shenyang Univ. of Technol. Shenyang 110023 China

A model of liquid ZA27 cast alloy is established according to molecular dynamics theory and an atomic structural model of co-existent a phase and liquid is also presented by means of computer programming. recursion method is adopted to calculate the electronic structure of RE (rare earth) in grains and around phase boundaries respectively. The calculation shows that RE is more stable around phase boundaries than in grains, which explains the fact that the solution of RE in a phase is less, and RE mainly aggregates in front of phase boundary. The calculations of bonding order integrals also show that RE in front of phases hardly solidify onto the grain surfaces as active element so as to prevent grains growth and refine the grains. As a result, the modification mechanism of RE may be explained from the view of electronic structure.

关键词： Atomic structural model recursion method Electronic structure Modification mechanism Rare easth

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Recursive method for generating weight enumerating functions of trellis codes

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ELECTRONICS LETTERS 2001年第12期37卷 773-774页

作者： Huang, XL Phamdo, N Ping, L SUNY Stony Brook Dept Elect & Comp Engn Stony Brook NY 11794 USA City Univ Hong Kong Dept Elect Engn Hong Kong Hong Kong Peoples R China

A simple recursive method for generating weight enumerating functions of trellis codes with finite lengths is presented. The proposed technique is conceptually simple and yet computationally efficient. It provides a c... 详细信息

关键词： Concatenated codes recursion method finite length Trellis codes

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Electronic structure of Zr-based metallic glasses

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JOURNAL OF ALLOYS AND COMPOUNDS 2009年第1-2期483卷 638-641页

作者： Hasegawa, M. Sato, H. Takeuchi, Bt. Soda, K. Mizutani, U. Nagoya Univ Dept Mat Sci & Engn Nagoya Aichi 4648603 Japan Aichi Univ Educ Dept Phys Kariya Aichi 4488542 Japan Nagoya Univ Ecotopia Sci Inst Nagoya Aichi 4648603 Japan Nagoya Univ Dept Quantum Engn Nagoya Aichi 4648603 Japan Toyota Phys & Chern Res Inst Nagakute Aichi 4801192 Japan

The electronic structure and phase stability of the Zr(66.7)Ni(33.3) and Zr(66.7)Cu(33.3) metallic glasses has been investigated by the recursion calculations method using a giant atom-cluster, of which arrangements of constituent atoms were determined by the Reverse Monte Carlo experimental structural studies reported before [T. Fukunaga, K. Itoh, T. Otomo, K. Mori, M. Sugiyama, H. Kato, M. Hasegawa, A. Hirata, Y. Hirotsu, Intermetallics 14(2006)893]. The electronic structure of the former is similar to that of the relevant Zr(2)Ni compound, while that of the latter is completely different from that of the relevant Zr(2)Cu compound. We have also calculated the band energy of the characteristic clusters in these metallic glasses. The smaller and Zr-richer these clusters are, the lower the band energy at the center of the cluster tends to be. The stability of these characteristic clusters of both metallic glasses can be explained by the total band energy based on the calculated local density of states and is consistent with the reported experimental Volonoi analysis. (C) 2008 Elsevier B.V. All rights reserved.

关键词： Metallic glass Electronic structure recursion method Cluster Band energy

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Theoretical study of the density of states and magnetic properties of electron-doped Sr_1-xCe_xCoO₃ compounds

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PHYSICA B-CONDENSED MATTER 2008年第10-11期403卷 1927-1932页

作者： Sun Aimin Zhang Xiue Kang Yonggang Yang Guofeng Wang Shunqing Zhang Tao Huang Guohai Zhu Haibin NW Normal Univ Coll Phys & Elect Engn Lanzhou 730070 Peoples R China Inst Disaster Prevent Sci & Technol Sanhe 065201 Hebei Peoples R China

Within the unrestricted Hartree-Fock approximation and the real space recursion method, we calculated the electronic structure of the Sr1-xCexCoO3 in the whole doping range 0.0 <= x <= 1.0. Various spin states in an enlarged double cell are investigated and five of them are the ground states at different doping concentration. The magnetic ground state of the doped system takes an intermediate-spin state for x < 0.02, a low-spin-intermediate-spin ferromagnetically ordered state for 0.02,<= x <= 0.38, and a low-spin-high-spin ferromagnetically ordered state for 0.38 <= x <= 0.79. For 0.79 <= x <= 0.9, the ground state of the system is the intermediate-spin chain-type anti-ferromagnetically ordered state, which is followed by the intermediate-spin nearest neighbor anti-ferromagnetically ordered state up to x = 1.0. The densities of states of all magnetic ground states are computed and their electronic and magnetic properties are discussed. (c) 2007 Elsevier B.V. All rights reserved.

关键词： recursion method Hartree-Fock approximation density of state doping concentration spin state magnetic ground state

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