公路客运市场建设项目的系统评价研究

本文通过对公路客运市场的生产和经营状况、所处的经营环境以及运力和客运需求进行了分析 ,提出了客运市场建设项目的评价指标体系 ,并且利用系统评价模型进行评价 ,得出了满意的结果     

On particle transport processes: A potential theoretic approach

This article provides a potential theoretic approach to the study of particle transport stochastic processes (x ( t,w) ,Y (t ?L?:) ) where x i t ) is the temporal evolution of a non-Plarkovian particle motion and y (t) is a Markovian physical process in the medium that governs the scattering or jump of the particle.As opposed to the perturbation technique, our approach immensely enhances the applicatory value of transport processes. We begin with a sample path construction of a transport process and continue with the existence ofcertain invariant measures. Expressing the particle motion x(t) as an additive functional of the transport process (x(t),y(t)), we establish a law of large number and a functional centxal limit theorem,(a Brownian motion approximation),for the non-Markovian particle motion.     

Analysis of a Quantum Subband Model for the Transport of Partially Confined Charged Particles

This paper is devoted to the analysis of a quantum subband model, which is presented as an alternative to the standard 3D Schr?dinger-Poisson system for modeling the transport of electrons strongly confined along one direction. This subband model is composed of quasistatic 1D Schr?dinger equations in the direction of the confinement, coupled to 2D time-dependent Schr?dinger equations describing the transport in the non-confined directions. Selfconsistent electrostatic interactions are also taken into account via the Poisson equation. This system is studied in the framework of the strong partial confinement asymptotics introduced in the article “Adiabatic approximation of the Schr?dinger-Poisson system with a partial confinement”, by Ben Abdallah, Méhats and Pinaud (SIAM J. Math. Anal. 36 (2005), 986–1013).     

Analysis of a Quantum Subband Model for the Transport of Partially Confined Charged Particles

This paper is devoted to the analysis of a quantum subband model, which is presented as an alternative to the standard 3D Schr?dinger-Poisson system for modeling the transport of electrons strongly confined along one direction. This subband model is composed of quasistatic 1D Schr?dinger equations in the direction of the confinement, coupled to 2D time-dependent Schr?dinger equations describing the transport in the non-confined directions. Selfconsistent electrostatic interactions are also taken into account via the Poisson equation. This system is studied in the framework of the strong partial confinement asymptotics introduced in the article “Adiabatic approximation of the Schr?dinger-Poisson system with a partial confinement”, by Ben Abdallah, Méhats and Pinaud (SIAM J. Math. Anal. 36 (2005), 986–1013).     

Characterization of optimal shapes and masses through Monge-Kantorovich equation

We study some problems of optimal distribution of masses, and we show that they can be characterized by a suitable Monge-Kantorovich equation. In the case of scalar state functions, we show the equivalence with a mass transport problem, emphasizing its geometrical approach through geodesics. The case of elasticity, where the state function is vector valued, is also considered. In both cases some examples are presented. Received February 10, 2000 / final version received July 21, 2000?Published online November 8, 2000     

Improving harvesting and transport planning within a sugar value chain

Recent economic pressures have forced the Australian sugar industry to achieve better integration and optimization of the cane harvesting and transport sectors of the value chain. The logistical and economic complexity of the harvesting and transport system was captured through the development of a modelling framework that effectively links several component models that describe the parts of the system. Through engaging in participatory research with representatives of a sugar region located at the north-east coast of Australia, we use this modelling framework to address some key industry issues in rationalizing rail track infrastructure and re-organizing harvesting. These issues were addressed by building component models for the modelling framework in the field of location science, namely the capacitated P-Median problem and spatial clustering. By applying the modelling framework and its component models to the case-study region, we explored a range of scenarios with a net cost reduction of up to AU$2?260?000 per year.     

运输问题的退化解及表解中0元的添加

在运输问题表上作业法中,有时会遇到退化解问题,这样在给调运方案时需要在调运表上添加0元,可是0应添在何处?大多数文献中均未具体给出或给出的结论有误,0元的添加不当有时会导致一系列问题出现,本文将讨论这些问题,且给出一个0元添加的确定的答案.     

Mass transportation and rough curvature bounds for discrete spaces

We introduce and study rough (approximate) lower curvature bounds for discrete spaces and for graphs. This notion agrees with the one introduced in [J. Lott, C. Villani, Ricci curvature for metric-measure spaces via optimal transport, Ann. of Math. 169 (2009), in press] and [K.T. Sturm, On the geometry of metric measure spaces. I, Acta Math. 196 (2006) 65-131], in the sense that the metric measure space which is approximated by a sequence of discrete spaces with rough curvature ?K will have curvature ?K in the sense of [J. Lott, C. Villani, Ricci curvature for metric-measure spaces via optimal transport, Ann. of Math. 169 (2009), in press; K.T. Sturm, On the geometry of metric measure spaces. I, Acta Math. 196 (2006) 65-131]. Moreover, in the converse direction, discretizations of metric measure spaces with curvature ?K will have rough curvature ?K. We apply our results to concrete examples of homogeneous planar graphs.     

Embedding optimal transports in statistical manifolds

We consider Monge-Kantorovich optimal transport problems on ? ^d , d ≥ 1, with a convex cost function given by the cumulant generating function of a probability measure. Examples include theWasserstein-2 transport whose cost function is the square of the Euclidean distance and corresponds to the cumulant generating function of the multivariate standard normal distribution. The optimal coupling is usually described via an extended notion of convex/concave functions and their gradient maps. These extended notions are nonintuitive and do not satisfy useful inequalities such as Jensen’s inequality. Under mild regularity conditions, we show that all such extended gradient maps can be recovered as the usual supergradients of a nonnegative concave function on the space of probability distributions. This embedding provides a universal geometry for all such optimal transports and an unexpected connection with information geometry of exponential families of distributions.     

SPIRAL SOLUTION TO THE TWO-DIMENSIONAL TRANSPORT EQUATIONS

The existence of spiral solution for the two-dimensional transport equations is considered in the present paper. Based on the notion of generalized solutions in the sense of Lebesgue-stieltjes integral, the global weak solution of transport equations which includes δ-shocks and vacuum is constructed for some special initial data.     

Fractional monodromy: parallel transport of homology cycles

A 2n-dimensional completely integrable system gives rise to a singular fibration whose generic fiber is the n-torus Tⁿ. In the classical setting, it is possible to define a parallel transport of elements of the fundamental group of a fiber along a path, when the path describes a loop around a singular fiber, it defines an automorphism of π₁(Tⁿ) called monodromy transformation [J.J. Duistermaat, On global action-angle coordinates, Communications on Pure and Applied Mathematics 33 (6) (1980) 687–706]. Some systems give rise to a non-classical setting, in which the path can wind around a singular fiber only by crossing a codimension 1 submanifold of special singular fibers (a wall), in this case a non-classical parallel transport can be defined on a subgroup of the fundamental group. This gives rise to what is known as monodromy with fractional coefficients [N. Nekhoroshev, D. Sadovskiì, B. Zhilinskiì, Fractional monodromy of resonant classical and quantum oscillators, Comptes Rendus Mathematique 335 (11) (2002) 985–988]. In this article, we give a precise meaning to the non-classical parallel transport. In particular we show that it is a homologic process and not a homotopic one. We justify this statement by describing the type of singular fibers that generate a wall that can be crossed, by describing the parallel transport in a semi-local neighbourhood of the wall of singularities, and by producing a family of 4-dimensional examples.     

Optical Tomography for Variable Refractive Index with Angularly Averaged Measurements

In optical tomography one seeks to use near-infrared light to determine the optical absorption and scattering properties of a medium X ? ? ⁿ . If the refractive index is constant throughout the medium, the steady-state case is modeled by the stationary linear transport equation in terms of the Euclidean metric. In this work we consider the case of variable refractive index where the dynamics are modeled by writing the transport equation in terms of a Riemannian metric; in the absence of interaction, photons follow the geodesics of this metric. In particular we study the problem where our measurements allow the application of an in-going flux depending on both position and direction, but we allow only a weighted average measurement of the out-going flux. We show that making measurements on all of ? X determines the extinction coefficient and that once this is known, under additional assumptions, measurements at a single point on ? X determine the scattering kernel.     

Global Small Solutions to an MHD‐Type System: The Three‐Dimensional Case

In this paper, we consider the global well‐posedness of a three‐dimensional incompressible MHD type system with smooth initial data that is close to some nontrivial steady state. It is a coupled system between the Navier‐Stokes equations and a free transport equation with a universal nonlinear coupling structure. The main difficulty of the proof lies in exploring the dissipative mechanism of the system due to the fact that there is a free transport equation of ? in the coupled equations and only the horizontal derivatives of ? is dissipative with respect to time. To achieve this, we first employ anisotropic Littlewood‐Paley analysis to establish the key L¹(? ⁺ ; Lip(?³)) estimate to the third component of the velocity field. Then we prove the global well‐posedness to this system by the energy method, which depends crucially on the divergence‐free condition of the velocity field. © 2014 Wiley Periodicals, Inc.     

Simulation and optimisation of intermodal barge transport networks

This is a summary of the author??s PhD thesis supervised by Gerrit Janssens and Cathy Macharis and defended on 7 May 2010?at the Hasselt University, Belgium. The thesis is written in English and is available from the author upon request. This work deals with two key aspects in the competitiveness of intermodal transport making use of inland navigation. The first part of the thesis studies bundling of freight in intermodal barge transport networks. Alternative bundling strategies for container barge transport are compared by means of discrete event simulation. Cooperation between inland barge terminals to bundle freight flows is modelled as a service network design problem. The second part relates to the initial and final journey by road in the intermodal barge transport chain. Pre- and end-haulage by road is modelled as a Full Truckload Pickup and Delivery Problem with Time Windows. A local search algorithm and deterministic annealing algorithm are proposed to find near-optimal solutions.     

Heat Transport Equations with Phonons and Electrons

In the framework of Extended Irreversible Thermodynamics, a model of heat transport due to phonons and electrons is developed. Compatibility with Second Law of Thermodynamics is exploited through a generalized Coleman-Noll procedure. A?system of nonlinear partial differential equations, ruling the evolution of the partial heat fluxes, is derived. Propagation of temperature waves through one-dimensional heat conductors is investigated as well.     

On the Evolution of Large Clusters in the Becker-D?ring Model

Summary. We consider the Becker-D?ring equations for large times. It is well-known [2] that if the total density of monomers exceeds a critical value, the excess density is contained in larger and larger clusters as time proceeds. We rigorously derive for general coefficients that the evolution of these large clusters is described by a nonlocal transport equation, which is for specific coefficients the classical coarsening model by Lifshitz, Slyozov, and Wagner (LSW). Our proof exploits the estimate of the energy and the energy dissipation rate given by the Lyapunov functional for the Becker-D?ring equations. We also provide a detailed asymptotic expansion of the higher-order dynamics.     

运输碳排放税及其分摊比例对制造商最优策略的影响

本文研究了政府收取运输碳排放税且排放责任由制造商和第三方物流(3PL)共同承担的环境下,处于卖方垄断地位的制造商如何制定生产策略和选择运输模式。重点分析了碳排放税和制造商承担的碳排放责任对运输模式选择策略的影响;进一步给出了碳排放税能够促使运输模式转移的条件以及碳排放分摊比例。研究结果显示,当3PL通过调整碳排放分摊比例来鼓励制造商选择清洁运输模式时,政府收取较小的碳排放税就能促使制造商转移运输模式。同时也发现,当碳排放税等于运输模式转移阈值时,虽然制造商选择两种运输模式的利润相同,但选择更清洁的运输模式能够大大降低碳排放总量,进一步 在企业的环保意识驱动下,制造商会选择更清洁的运输模式。因此,我们的研究结果为制造商可持续运作和政府制定合理的碳排放税提供一定的决策参考。     

A Riemannian interpolation inequality à la Borell, Brascamp and Lieb

A concavity estimate is derived for interpolations between L ¹(M) mass densities on a Riemannian manifold. The inequality sheds new light on the theorems of Prékopa, Leindler, Borell, Brascamp and Lieb that it generalizes from Euclidean space. Due to the curvature of the manifold, the new Riemannian versions of these theorems incorporate a volume distortion factor which can, however, be controlled via lower bounds on Ricci curvature. The method uses optimal mappings from mass transportation theory. Along the way, several new properties are established for optimal mass transport and interpolating maps on a Riemannian manifold. Oblatum 1-XII-2000 & 3-V-2001?Published online: 13 August 2001     

Adiabatic charge transport and the Kubo formula for Landau‐type Hamiltonians

The adiabatic charge transport is investigated in a two‐dimensional Landau model perturbed by a bounded potential at zero temperature. We show that if the Fermi level lies in a spectral gap, then in the adiabatic limit the accumulated excess Hall charge is given by the linear response Kubo‐?treda formula. The proof relies on the expansion of Nenciu, some generalized phase space estimates, and a bound on the speed of propagation. © 2004 Wiley Periodicals, Inc.     

From the Schrödinger problem to the Monge–Kantorovich problem

The aim of this article is to show that the Monge–Kantorovich problem is the limit, when a fluctuation parameter tends down to zero, of a sequence of entropy minimization problems, the so-called Schrödinger problems. We prove the convergence of the entropic optimal values to the optimal transport cost as the fluctuations decrease to zero, and we also show that the cluster points of the entropic minimizers are optimal transport plans. We investigate the dynamic versions of these problems by considering random paths and describe the connections between the dynamic and static problems. The proofs are essentially based on convex and functional analysis. We also need specific properties of Γ-convergence which we didn?t find in the literature; these Γ-convergence results which are interesting in their own right are also proved.