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91.
IntroductionWith the development of modern industry, various pollutants discharge into the air,rivers, lakes and oceans, which makes the environmental qualities worse and has bad effectson the mankind’s health and the sustained development of industry an…  相似文献   
92.
Variable Order and Distributed Order Fractional Operators   总被引:1,自引:0,他引:1  
Many physical processes appear to exhibit fractional order behavior thatmay vary with time or space. The continuum of order in the fractionalcalculus allows the order of the fractional operator to be considered asa variable. This paper develops the concept of variable and distributedorder fractional operators. Definitions based on the Riemann–Liouvilledefinition are introduced and the behavior of the new operators isstudied. Several time domain definitions that assign different argumentsto the order q in the Riemann–Liouville definition are introduced. Foreach of these definitions various characteristics are determined. Theseinclude: time invariance of the operator, operator initialization,physical realization, linearity, operational transforms, and memorycharacteristics of the defining kernels.A measure (m 2) for memory retentiveness of the order history isintroduced. A generalized linear argument for the order q allows theconcept of `tailored' variable order fractional operators whose m 2 memory may be chosen for a particular application. Memory retentiveness (m 2) andorder dynamic behavior are investigated and applications are shown.The concept of distributed order operators where the order of thetime based operator depends on an additional independent (spatial)variable is also forwarded. Several definitions and their Laplacetransforms are developed, analysis methods with these operators aredemonstrated, and examples shown. Finally operators of multivariable anddistributed order are defined and their various applications areoutlined.  相似文献   
93.
The kinetics of crack growth in a viscoelastic orthotropic plate made of a composite material is analyzed. The external load is the superposition of a cyclic load and a constant tensile load. The level of the tensile load is assumed to exceed the amplitude of the cyclic load. The kinetic curves are compared with the constant tension curves. The effect of the cyclic component is studied.Translated from Prikladnaya Mekhanika, Vol. 40, No. 9, pp. 116–122, September 2004.  相似文献   
94.
The sloshing problem is considered in a half-space covered by a rigid dock with apertures. The dependence of the fundamental sloshing frequency on the shape of the free surface region is studied. It is proved that the inequality holds between the fundamental eigenvalues corresponding to two different regions if some conditions are fulfilled. These conditions are verified for particular classes of regions of a fixed area in order to demonstrate that the disk yields the maximum of the fundamental eigenvalue for each of these classes. On the other hand, examples of regions are constructed for which the fundamental eigenfrequency is larger than that for the circular aperture of the same area and even as large as one wishes. To cite this article: V. Kozlov, N. Kuznetsov, C. R. Mecanique 330 (2002) 723–728.  相似文献   
95.
IntroductionInvestigatingthefollowingboundaryprobleminordinarydifferentialequation :¨x+f(t,x(t) ) =0 ,a<t<b,αx(a) -β x(a) =0 ,γx(b) +δ x(b) =0 ,( 1 )whereα ,β,γ ,δ≥ 0 ,Δ=(b-a)αγ+αδ+ βγ>0 .f(t,s)maybesingularint =a ,b.Ithasbeendirectlyverifiedthatx(t)isthesolutionof( 1 )inC2 [a ,b]ifandonlyifx(…  相似文献   
96.
REMARK ON STABILITY OF ISHIKAWA ITERATIVE PROCEDURES   总被引:2,自引:0,他引:2  
1 IntroductionandPreliminariesSupposeEisarealBanachspaceandTisaselfmapofE .Supposex0 ∈Eandxn+1=f(T ,xn)definesaniterationprocedurewhichyieldsasequenceofpoints xn ∞n=0 inE .Foranexample ,thefunctioniterationxn+1=f(T ,xn) =Tx0 .SupposeF(T) =x∈E :Tx=x ≠ andthat xn convergess…  相似文献   
97.
This article focuses on the formulation of a hysteretic model used as anisolator restoring force model. The proposed model is based on operatorgoverning input and output functions that depend on the deflection andthe restoring force of the isolator. First, the mathematical formulationis demonstrated, then the hysteretic model proposed is applied toisolators having different types of behavior. The model parameters aresought using the experimental force-deflection loop of each of theisolators studied. Next, the transient response of a flexible structuremounted on an all-metal isolator is predicted by coupling the firstorder differential equation of the restoring force and the second orderdifferential equations of the structure's motion. The experimentalinvestigation validates the proposed hysteretic model applied to theall-metal mount.  相似文献   
98.
This paper deals with the spectral and qualitative problems associated with the one-dimensional ergodic Schrödinger equation. Let A 2 be the set of those energies for which the real projective flow admits an invariant linear measure with square integrable density function. On this set we calculate the directional derivative of the Floquet coefficient and prove the existence of a nontangential limit of the Weyl m-functions in the L 1-topology. In particular, we verify that the known Dieft–Simon inequality for the derivative of the rotation number obtained from Kotani's theory is in fact an equality. In the bounded orbit case we deduce the uniform boundedness of the Weyl m-functions and obtain necessary and sufficient conditions to assure their uniform convergence.  相似文献   
99.
We consider the Schrödinger operator on two types of domains depending on a small parameter : dumbbell domains and thin domains with varying orders of thinness. In both situations we compare the eigenvalues and eigenvectors of the Schrödinger operator with the corresponding eigenvalues and eigenvectors of a limit operator defined on the limit domain.  相似文献   
100.
An inverse problem for identification of the coefficient in heat-conduction equation is considered. After reducing the problem to a nonlinear ill-posed operator equation, Newton type iterative methods are considered. The implicit iterative method is applied to the linearized Newton equation, and the key step in the process is that a new reasonable a posteriori stopping rule for the inner iteration is presented. Numerical experiments for the new method as well as for Tikhonov method and Bakushikskii method are given, and these results show the obvious advantages of the new method over the other ones.  相似文献   
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