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Partial Improvement of Traditional Grey-Markov Model and Its Application on Fault Prediction

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第4期34卷 449-455页

作者： Li Yongping Jia Cili Air Transportation College Shanghai University of Engineering Science

Modeling experiences of traditional grey-Markov show that the prediction results are not accurate when analyzed data are rare and *** it is necessary to revise or improve the original modeling procedure of the grey-Markov(GM)***,a new idea is brought forward that the Markov theory is used twice,where the first time is to extend the original data and the second to calculate and estimate the residual *** by comparing the original data sequence from a fault prediction case with the simulation sequence produced by the use of GM(1,1) and the new GM method,results are conforming to the original ***,an assumption of GM model is put forward as the future work.

关键词： grey-Markov model GM(1,1) residual error

Series Solution for Rotating Flow of an Upper Convected Maxwell Fluid over a Stretching Sheet

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Communications in Theoretical Physics 2011年第10期56卷 740-744页

作者： M.Sajid Z.Iqbal T.Hayat S.Obaidat Theoretical Plasma Physics Division PINSTECHP.O.Nilore Islamabad 44000Pakistan Department of Mathematics Quaid-i-Azam University 45320 Islamabad 44000Pakistan Department of Mathematics College of ScienceKing Saud UniversityP.O.Box.2455Riyadh 11451Saudi Arabia

The equations for two-dimensional flow of an upper convected Maxwell （UCM） fluid in a rotating frame are modeled. The resulting equations are first simplified by a boundary layer approach and then solved by a homotopy analysis method （HAM）. Convergence of series solution is discussed through residual error curves. The results of the influence of viscoelastic and rotation parameters are plotted and discussed.

关键词： rotating flow stretching sheet UCM fluid HAM solution residual error

Effects of residual motion compensation errors on the performance of airborne along-track interferometric SAR

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Frontiers of Information Technology & Electronic Engineering 2016年第10期17卷 1095-1105页

作者： Hui ZHANG Jun HONG Xiao-lan QIU Ji-chuan LI Fang-fang LI Feng MING Institute of Electronics Chinese Academy of Sciences Beoing 100190 China University of the Chinese Academy of Sciences Beijing 100190 China Key Laboratory of Technology in Geo-spatial Information Processing and Application Systems Beijing 100190 China Science and Technology on Millimeter-Wave Laboratory Beijing 100854 China

Two approximations, center-beam approximation and reference digital elevation model （DEM） approximation, are used in synthetic aperture radar （SAR） motion compensation procedures. They usually introduce residual motion compensation errors for airborne single-antenna SAR imaging and SAR interferometry. In this paper, we investigate the effects of residual uncompensated motion errors, which are caused by the above two approximations, on the performance of airborne along-track interferometric SAR （ATI-SAR）. The residual uncompensated errors caused by center-beam approximation in the absence and in the presence of elevation errors are derived, respectively. Airborne simulation parameters are used to verify the correctness of the analysis and to show the impacts of residual uncompensated errors on the interferometric phase errors for ATI-SAR. It is shown that the interferometric phase errors caused by the center-beam approximation with an accurate DEM could be neglected, while the interferometric phase errors caused by the center-beam approximation with an inaccurate DEM cannot be neglected when the elevation errors exceed a threshold. This research provides theoretical bases for the error source analysis and signal processing of airborne ATI-SAR.

关键词： Synthetic aperture radar (SAR) Along-track interferometric Motion compensation residual error Interferometric phase

An Effcient Computational Method for Differential Equations of Fractional Type

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Computer Modeling in Engineering & Sciences 2022年第10期 47-65页

作者： Mustafa Turkyilmazoglu Department of Mathematics Hacettepe UniversityAnkara06532Turkey Department of Medical Research China Medical University HospitalChina Medical UniversityTaichung40447Taiwan

An effective solution method of fractional ordinary and partial differential equations is proposed in the present *** standard Adomian Decomposition Method(ADM)is modified via introducing a functional term involving both a variable and a parameter.A residual approach is then adopted to identify the optimal value of the embedded parameter within the frame of L^(2) *** experiments on sample problems of open literature prove that the presented algorithm is quite accurate,more advantageous over the traditional ADM and straightforward to implement for the fractional ordinary and partial differential equations of the recent focus of mathematical *** performance of the method is further evidenced against some compared commonly used numerical techniques.

关键词： Fractional differential equations Adomian decomposition method optimal data residual error

Microwave-Assisted Transition Metal Nanostructure Synthesis: Power-Law Signature Verification

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American Journal of Analytical Chemistry 2023年第8期14卷 326-349页

作者： Victor J. Law Denis P. Dowling School of Mechanical and Materials Engineering University College Dublin Dublin Ireland

A power-law (y = cxn) signature between process energy budget (kJ) and process energy density (kJ·ml-1) of microwave-assisted synthesis of silver and gold nanostructures has been recently described [Law and Denis. AJAC, 14(4), 149-174, (2023)]. This study explores this relation further for palladium, platinum, and zinc oxide nanostructures. Parametric cluster analysis and statistical analysis is used to test the power-law signature of over four orders of magnitude as a function of six microwave applicator-types metal precursor, non-Green Chemistry synthesis and claimed Green Chemistry. It is found that for the claimed Green Chemistry, process energy budget ranges from 0.291 to 900 kJ, with a residual error ranging between −33 to +25.9 kJ·ml-1. The non-Green Chemistry synthesis has a higher process energy budget range from 3.2 kJ to 3.3 MJ, with a residual error of −33.3 to +245.3 kJ·ml-1. It is also found that the energy profile over time produced by software controlled digestion applicators is poorly reported which leads to residual error problematic outliers that produce possible phase-transition in the power-law signature. The original Au and Ag database and new Pd, Pt and ZnO database (with and without problematic outliers) yield a global microwave-assisted synthesis power-law signature constants of c = 0.7172 ± 0.3214 kJ·ml-1 at x-axes = 0.001 kJ, and the exponent, n = 0.791 ± 0.055. The information in this study is aimed to understand variations in historical microwave-assisted synthesis processes, and develop new scale-out synthesis through process intensification.

关键词： Microwave-Assisted Synthesis Pd Ag Pt Au ZnO Power-Law residual error Statistical Analysis Parametric Cluster Analysis