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82.
杨殿海 《鞍山科技大学学报》2004,27(1):31-33
桥头跳车会增加行车风险并且会大大增加每年的养护费用.本文作者根据多年的养护管理及施工经验,对桥头跳车的成因从设计、施工及运营使用几方面进行了分析并提出了几种处理方法,尤其是对桥头搭板和土工格栅网两种目前工程界常用方法从设计机理到施工实践进行了比较详细的论述,同时对设计机理方面引入了相应的数学模型. 相似文献
83.
连铸板坯外形的在线检测方法 总被引:2,自引:1,他引:1
介绍了板坯外形在线检测的测量原理,计算方法,并给出了实验测量方法,过程及计算机图像处理系统的处理结果,该方法简单,实用,精度较高。 相似文献
84.
一类4阶Feigenbaum映射的拟极限集 总被引:5,自引:2,他引:3
讨论一类4阶Feigenbaum映射的拟极限集及其Hausdorff维数, 并证明对任意t∈(0,log31/2+12), 总存在一类具有简单轨 的4阶非单谷Feigenbaum映射, 它有一个以t为Hausdorff维数的拟极限集. 相似文献
85.
Jonathan M. Borwein 《Optimization Letters》2007,1(1):21-32
This paper is a companion to a lecture given at the Prague Spring School in Analysis in April 2006. It highlights four distinct variational methods of proving that a finite dimensional Chebyshev set is convex and hopes to inspire renewed work on the open question of whether every Chebyshev set in Hilbert space is convex. 相似文献
86.
Monia Belhabri Jack Legrand Nathalie LeSauze Abdellah Arhaliass 《Particle & Particle Systems Characterization》2004,21(5):365-371
Emulsions are of great importance to industry. They are involved in many engineering operations, including chemical reactions, extraction, emulsification and suspension polymerization, etc. However, an important problem for these processes is how to control the size distribution of the dispersed phase. Indeed, off‐line analysis of the emulsion may generate uncertainties due to sampling and dilution of the product, which are likely to change the dispersion state and physico‐chemical properties. In this work, an on‐line optical method is proposed to characterize dispersed media in real flowing conditions. This method is based on the time‐analysis of back‐scattered light fluctuations. The present paper deals with the development of this method and its application to dispersions of alumina in water. The results obtained with the on‐line optical method are compared with those acquired by classical laser light scattering and microscopy. 相似文献
87.
Ekatherina A. Karatsuba 《Numerical Algorithms》2007,45(1-4):127-137
A new approach to the study of the Jaynes–Cummings sum, which determines the atomic inversion in quantum model of a single
two-level atom interacting with a single mode of the quantized radiation field, based on the number theory theorems on approximation
of trigonometric sums is presented.
相似文献
88.
A. Vukics H. Ritsch 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2007,44(3):585-599
We present a framework for efficiently performing Monte Carlo
wave-function simulations in cavity QED with moving particles. It
relies heavily on the object-oriented programming paradigm as realised
in C++, and is extensible and applicable for simulating open
interacting qua
ntum dynamics in general. The user is provided with a
number of “elements”, e.g. pumped moving particles, pumped lossy
cavity modes, and various interactions to compose complex interacting
systems, which contain several particles moving in electromagnetic
fields of various configurations, and perform wave-function
simulations on such systems. A number of tools are provided to
facilitate the implementation of new elements. 相似文献
89.
Joe Warren Scott Schaefer Anil N. Hirani Mathieu Desbrun 《Advances in Computational Mathematics》2007,27(3):319-338
In this paper we provide an extension of barycentric coordinates from simplices to arbitrary convex sets. Barycentric coordinates
over convex 2D polygons have found numerous applications in various fields as they allow smooth interpolation of data located
on vertices. However, no explicit formulation valid for arbitrary convex polytopes has been proposed to extend this interpolation
in higher dimensions. Moreover, there has been no attempt to extend these functions into the continuous domain, where barycentric
coordinates are related to Green’s functions and construct functions that satisfy a boundary value problem. First, we review
the properties and construction of barycentric coordinates in the discrete domain for convex polytopes. Next, we show how
these concepts extend into the continuous domain to yield barycentric coordinates for continuous functions. We then provide
a proof that our functions satisfy all the desirable properties of barycentric coordinates in arbitrary dimensions. Finally,
we provide an example of constructing such barycentric functions over regions bounded by parametric curves and show how they
can be used to perform freeform deformations.
相似文献
90.
An extremum problem is embedded in a parametric scheme which contains, as a particular case, the classic perturbation function. The introduction of the image of the embedded problem allows one to derive a generalized duality and, in particular, Lagrangian and Fenchel duality. 相似文献