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991.
992.
We consider a strongly coupled PDE–ODE system that describes the influence of a slow and large vehicle on road traffic. The model consists of a scalar conservation law accounting for the main traffic evolution, while the trajectory of the slower vehicle is given by an ODE depending on the downstream traffic density. The moving constraint is expressed by an inequality on the flux, which models the bottleneck created in the road by the presence of the slower vehicle. We prove the existence of solutions to the Cauchy problem for initial data of bounded variation. 相似文献
993.
《Journal of Differential Equations》2014,257(8):2950-2983
We present a rigorous numerical proof based on interval arithmetic computations categorizing the linearized and nonlinear stability of periodic viscous roll waves of the KdV–KS equation modeling weakly unstable flow of a thin fluid film on an incline in the small-amplitude KdV limit. The argument proceeds by verification of a stability condition derived by Bar–Nepomnyashchy and Johnson–Noble–Rodrigues–Zumbrun involving inner products of various elliptic functions arising through the KdV equation. One key point in the analysis is a bootstrap argument balancing the extremely poor sup norm bounds for these functions against the extremely good convergence properties for analytic interpolation in order to obtain a feasible computation time. Another is the way of handling analytic interpolation in several variables by a two-step process carving up the parameter space into manageable pieces for rigorous evaluation. These and other general aspects of the analysis should serve as blueprints for more general analyses of spectral stability. 相似文献
994.
浙江杜鹃花属植物的研究 总被引:3,自引:0,他引:3
本文报道了浙江产杜鹃花属植物16 种及 1 变型其中白花满山红为新变型,丁香杜 鹃和江西杜码为浙江分布新记录.根据最新分类系统,本属分为 5 个亚属,在浙江都有 它们的代表,说明浙江的杜鹃花属植物在该属系统研究中的地位,此外,文中还附有分种 检 索表和种类列举 ( 分布、用途 ) 相似文献
995.
A collocation method based on the Bessel functions of the first kind for singular perturbated differential equations and residual correction 下载免费PDF全文
Şuayip Yüzbaşı 《Mathematical Methods in the Applied Sciences》2015,38(14):3033-3042
In this paper, a collocation method is given to solve singularly perturbated two‐point boundary value problems. By using the collocation points, matrix operations and the matrix relations of the Bessel functions of the first kind and their derivatives, the boundary value problem is converted to a system of the matrix equations. By solving this system, the approximate solution is obtained. Also, an error problem is constructed by the residual function, and it is solved by the presented method. Thus, the error function is estimated, and the approximate solutions are improved. Finally, numerical examples are given to show the applicability of the method, and also, our results are compared by existing results. Copyright © 2014 JohnWiley & Sons, Ltd. 相似文献
996.
Exact constants in Poincaré type inequalities for functions with zero mean boundary traces 下载免费PDF全文
In this paper, we investigate Poincaré type inequalities for the functions having zero mean value on the whole boundary of a Lipschitz domain or on a measurable part of the boundary. We find exact and easily computable constants in these inequalities for some basic domains (rectangles, cubes, and right triangles) and discuss applications of the inequalities to quantitative analysis of partial differential equations. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
997.
Let be a densely defined operator on a Banach space X. Characterizations of when generates a C0‐semigroup on X are known. The famous result of Lumer and Phillips states that it is so if and only if is dissipative and is dense in X for some . There exists also a rich amount of Banach space results concerning perturbations of dissipative operators. In a recent paper Tyran–Kamińska provides perturbation criteria of dissipative operators in terms of ergodic properties. These results, and others, are shown to remain valid in the setting of general non–normable locally convex spaces. Applications of the results to concrete examples of operators on function spaces are also presented. 相似文献
998.
A Model for Evaluation of Transport Policies in Multimodal Networks with Road and Parking Capacity Constraints 总被引:1,自引:0,他引:1
Zhi-Chun Li Hai-Jun Huang William H. K. Lam S. C. Wong 《Journal of Mathematical Modelling and Algorithms》2007,6(2):239-257
This paper presents a model for evaluation of transport policies in multimodal networks with road and parking capacity constraints.
The proposed model simultaneously considers choices of travelers on route, parking location and mode between auto and transit.
In the proposed model, it is assumed that auto drivers make a simultaneous route and parking location choice in a user equilibrium
manner, and the modal split between auto and transit follows a multinomial logit formulation. A mathematical programming model
with capacity constraints on road link and parking facilities is proposed that generates optimality conditions equivalent
to the requirements for multimodal network equilibrium. An augmented Lagrangian dual algorithm embedded by partial linearization
approach is developed to solve the proposed model. Numerical results on two example networks are presented to illustrate the
proposed methodology. The results show that the service level of transit, parking charges, road link and parking capacities,
and addition of a new parking location may bring significant impacts on travelers’ behavior and network performance. In addition,
transport policies may result in paradoxical phenomenon. 相似文献
999.
Iva Franjić 《Mathematische Nachrichten》2015,288(17-18):2016-2027
This paper aims to contribute to the exploration of quadrature formulae by proving that the error of a quadrature formula has the Schur‐convexity property. The emphasis is on the quadrature formulae with the maximum degree of precision. The Schur‐convexity of the error has an interesting implication – the monotonicity of the error. Namely, it turns out that the absolute value of the error is always smaller on a smaller interval (of the two which share the same midpoint). 相似文献
1000.
The existence of invariant generators for distributions satisfying a compatibility condition with the symmetry algebra is proved. 相似文献