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141.
In this paper we introduce a new class of facet-inducing inequalities for the Windy Rural Postman Problem and the Windy General
Routing Problem. These inequalities are called Zigzag inequalities because they cut off fractional solutions containing a
zigzag associated with variables with 0.5 value. Two different types of inequalities, the Odd Zigzag and the Even Zigzag inequalities,
are presented. Finally, their application to other known Arc Routing Problems is discussed. 相似文献
142.
X.S. Chen V. Dohm 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,5(3):529-542
We derive exact results for several thermodynamic quantities of the O
(
n
) symmetric field theory in the limit in a finite d-dimensional hypercubic geometry with periodic boundary conditions. Corresponding results are derived for an O
(
n
) symmetric model on a finite d-dimensional lattice with a finite-range interaction. The leading finite-size effects near Tc of the field-theoretic model are compared with those of the lattice model. For 2 <
d
< 4, the finite-size scaling functions are verified to be universal. For d
> 4, significant lattice effects are found. Finite-size scaling in its usual simple form does not hold for d
> 4 but remains valid in a generalized form with two reference lengths. The finite-size scaling functions of the field theory turn out to be nonuniversal whereas those of the lattice model are independent of the nonuniversal model parameters. In particular, the field-theoretic model exhibits finite-size
effects whose leading exponents differ from those of the lattice model. The widely accepted lowest-mode approach is shown
to fail for both the field-theoretic and the lattice model above four dimensions.
Received: 20 October 1997 / Accepted: 5 March 1998 相似文献
143.
A core-envelope model for superdense matter distribution with the feature- core consisting of anisotropic fluid distribution
and envelope with isotropic fluid distribution is reported on the background of pseudospheroidal space-time. The physical
plausibility of the model is examined analytically and numerically. 相似文献
144.
二次微分系统的中心条件和通积分 总被引:1,自引:0,他引:1
本文给出在中国分类之下二次微分系统有中心时两种情况的通积分. 相似文献
145.
P. Snabre F. Magnifotcham 《The European Physical Journal B - Condensed Matter and Complex Systems》1998,4(3):369-377
The continuous emission of gas bubbles from a single ejection orifice immersed in a viscous fluid is considered. We first
present a semi empirical model of spherical bubble growth under constant flow conditions to predict the bubble volume at the
detachment stage. In a second part, we propose a physical model to describe the rise velocity of in-line interacting bubbles
and we derive an expression for the net viscous force acting on the surrounding fluid. Experimental results for air/water-glycerol
systems are presented for a wide range of fluid viscosity and compared with theoretical predictions. An imagery technique was used to determine the bubble size and rise velocity.
The effects of fluid viscosity, gas flow rate, orifice diameter and liquid depth on the bubble stream dynamic were analyzed.
We have further studied the effect of large scale recirculation flow and the influence of a neighbouring bubble stream on
the bubble growth and rising velocity.
Received: 23 July 1997 / Revised: 16 December 1997 / Accepted: 11 May 1998 相似文献
146.
We establish the existence and stability results for periodic nonautonomous uniform forward attractors of periodic general dynamical systems (set-valued dynamical systems). We also investigate the dynamical behavior of nonautonomous periodic differential inclusion x′(t)∈f(t,x(t)) on Rm with only upper semi-continuous right-hand side by applying the abstract results. Firstly, we show that if the system has a compact uniformly attracting set, then it has a periodic nonautonomous uniform forward attractor A. Secondly, we prove that A is robust with respect to both internal and external perturbations. Finally, we apply the robustness result to discuss the effects of small time delays to asymptotic stability of the system. 相似文献
147.
Abdellah Bnouhachem Muhammad Aslam Noor 《Journal of Mathematical Analysis and Applications》2006,324(2):1195-1212
In this paper, we suggest and analyze a new inexact proximal point method for solving general variational inequalities, which can be considered as an implicit predictor-corrector method. An easily measurable error term is proposed with further relaxed error bound and an optimal step length is obtained by maximizing the profit-function and is dependent on the previous points. Our results include several known and new techniques for solving variational inequalities and related optimization problems. Results obtained in this paper can be viewed as an important improvement and refinement of the previously known results. Preliminary numerical experiments are included to illustrate the advantage and efficiency of the proposed method. 相似文献
148.
J. Iwaniszewski 《Il Nuovo Cimento D》1995,17(7-8):819-825
Summary The phenomenon of stochastic resonance is predicted in a monostable system displaying transient bimodality during the evolution.
The signal-to-noise ratio as a function of the noise intensity calculated within the rate equation theory with many simplifying
assumptions exhibits a promising peak. The numerical simulations are also reported.
Paper presented at the International Workshop ?Fluctuations in Physics and Biology: Stochastic Resonance, Signal Processing
and Related Phenomena?, Elba, 5–10 June 1994. 相似文献
149.
Summary We consider the transmission of a periodic signal by noisy threshold devices. A general expression for the input-output characteristic
is developed and applied to two particular threshold devices. It is shown that the amplitude of the signal output shows in
the subthreshold regime a maximum as a function of the noise strength—the fingerprint of stochastic resonance.
Paper presented at the International Workshop ?Fluctuations in Physics and Biology: Stochastic Resonance, Signal Processing
and Related Phenomena?, Elba 5–10 June 1994. 相似文献
150.
新一代SDH关键技术和动态带宽分配的实现 总被引:2,自引:0,他引:2
首先介绍了为解决传说SDH传输技术存在的多业务(主要是宽带数据业务)承载能力不足和带宽分配缺乏灵活性等问题而出现的一系列新技术(如虚级联、链路容量调整方案,通用成帧规程等)的基本原理和特点,并在此基础上进一步讨论了如何实现SDH带宽动态分配的问题。 相似文献