铁路含油废水中油的形态和粒度分布

用重量法和紫外分光光度法研究了铁路内燃机务段、蒸汽机务段和车辆段含油废水中油的形态分布规律。废水中的油有１５％￣５０％上浮至水面，４０％￣７０％随悬浮物下沉，只有４％￣３０％的油滞留水中，此外使用显微镜计数法测定了油水乳状液中的油珠粒径，废水中油珠粒径一般在３０μｍ以下，并得了油珠在粒度分布和重量分数。     

船舶火灾应急程序之探讨

探讨船舶目前普遍采用的火灾应急程序,分析存在的问题,提出解决的方法,为进一步完善船舶消防安全工作提供参考。     

关于多部图Kn(t)的{K4-e,S3}-强制分解

设n,t为正整数,以K_n(t)表示基于顶点集X=■X_i上的完全n部图。文章证明了(Kn(t),｛K4-e,S3｝)—强制分解存在当且仅当n≥3且(n,t)≠(3,2)。     

现代多媒体课堂教学若干问题浅析

随着信息化的发展与普及,仅靠传统的教学方法和课堂教学结构,已不能满足现代社会对人材培养的需求,多媒体课堂教学已经成为课堂教学的一个生力军。本文就这些年的教学情况对多媒体课堂教学中存在的几个问题进行了分析,并根据多媒体课堂教学的特点提出了自己的看法。     

Existence of simultaneous route and departure choice dynamic user equilibrium

This paper is concerned with the existence of the simultaneous route-and-departure choice dynamic user equilibrium (SRDC-DUE) in continuous time, first formulated as an infinite-dimensional variational inequality in Friesz et al. (1993). In deriving our existence result, we employ the generalized Vickrey model (GVM) introduced in Han et al., 2013a, Han et al., 2013b to formulate the underlying network loading problem. As we explain, the GVM corresponds to a path delay operator that is provably strongly continuous on the Hilbert space of interest. Finally, we provide the desired SRDC-DUE existence result for general constraints relating path flows to a table of fixed trip volumes without invocation of a priori bounds on the path flows.     

The corridor problem with discrete multiple bottlenecks

This paper presents a transparent approach to the analysis of dynamic user equilibrium and clarifies the properties of a departure-time choice equilibrium of a corridor problem where discrete multiple bottlenecks exist along a freeway. The basis of our approach is the transformation of the formulation of equilibrium conditions in a conventional “Eulerian coordinate system” into one in a “Lagrangian-like coordinate system.” This enables us to evaluate dynamic travel times easily, and to achieve a deep understanding of the mathematical structure of the problem, in particular, about the properties of the demand and supply (queuing) sub-models, relations with dynamic system optimal assignment, and differences between the morning and evening rush problems. Building on these foundations, we establish rigorous results on the existence and uniqueness of equilibria.