Spatial competition and regulatory change in the grain handling and transportation system in western Canada

The grain handling and transportation system (GHTS) has been a defining component of the western Canadian economy since the early part of the last century. Only two major railways serve the grain handling industry, so the potential for the exercise of market power in transportation appears to be significant. In fact, spatially oriented regulations applicable to railways exist in Canada to mitigate this, but to date they have not often been used by shippers. While the reasons for this are not completely clear, we suggest that the regulations are now inadequate for the current state of the GHTS. Using a unique data set from the year 2000, we assess the effect on the grain handling industry of modifications to these regulations, and find that significant gains for shippers from these modifications are possible. These gains are computed to be on the order of C$10–15 million per year for grain shippers alone. We would like to thank conference and presentation participants (Transportation Research Board, Canadian Agricultural Economics Society, University of British Columbia, University of Leeds and California State University, Long Beach) as well as the anonymous reviewers who commented on the earlier versions of this paper. We would also like to acknowledge support from the Saskatchewan Department of Highways.     

工字形铝合金偏心压杆平面外稳定承载力研究

运用ANSYS软件对工字形铝合金偏心压杆平面外稳定承载力进行了研究,分别讨论初弯曲、残余应力和截面厚度偏差等缺陷对杆件平面外稳定承载力的影响,提出稳定系数曲面的概念,指出平面外稳定系数是相对偏心率e′和相对长细比λ的二元函数,在空间上为一连续的曲面。并对不同截面尺寸杆件的平面外稳定系数进行大量计算分析,以此为基础拟合出了平面外稳定系数曲面=f(λ,e′)的函数表达式,可供设计参考。     

Fluid filling of a membrane tube with self-weight

The filling of a membrane tube with self-weight by a fluid is studied theoretically for the first time. The fundamental problem depends on two non-dimensional parameters, $\beta$ and $\gamma$ which represent the importance of internal pressure and membrane self-weight respectively. The nonlinear equations are solved by an efficient numerical integration method. It is found that membrane self-weight has considerable effect on the tube geometry and the tension of the membrane at low filling pressures.     

岩土工程档案的利用需求及管理对策

本文通过作者多年对岩土工程档案管理工作的实践,结合岩土工程档案本身的特点,总结了岩土工程档案利用需求的相关特性。     

大型商场家电类商品火灾蔓延特性研究

采用实尺实验的方法，针对模拟家电类商品的标准组件，就商品货架摆放和堆垛摆放的不同形式，研究在无水喷淋保护的条件下火灾发展和火焰传播的特性。得出该类商品发生火灾时达到旺盛期的时间、垂直方向和水平方向火焰传播速度以及火灾载荷对火灾发展影响的规律。     

CFRP筋作体外预应力束的简支梁桥设计研究

本文介绍了c筋在预应力混凝土公路梁桥建设中的应用。该桥为整体现浇25m跨径简支梁,采用CFRP筋中的碳绞线(Carbon Fiber Composite Cable)作为体外预应力束。文中论述了设计中应关注的主要问题,运用理论方法和有限元方法对结构作了全面分析,并在造价上与普通预应力混凝土梁桥作了比较。     

从民居建筑布局看“堂文化”的神圣表述——“堂文化”所呈现的中国文化思维模式论之一

民居里的堂屋是民居建筑里的“神圣空间”,在我们阅读这种神圣空间的同时,我们不仅能够读出中国文化的核心思想观念,而且可以读出中国文化里的思维模式,以及中国文化的结构体系。而这些与中国民居建筑手法融合,使得民居的“堂”成为中国文化中典型的神圣“话语”符号。     

淮河防汛调度设施工程结构抗震设计

以“淮河防汛调度设施工程”这一具有复杂体型的高层建筑结构为实例,从理论分析和抗震设计上对其进行了详细的分析和讨论,重点介绍了结构抗震设计过程中的特殊处理措施,得出了关于该类结构抗震设计的几点结论。     

奢华的简约

香港,繁华而喧嚣,漫步在大街上,萦绕在耳际永远是无边的噪杂声,而汹涌而至的人群又仿佛随时都有淹没我们的可能,这让生活在大都市中的男女备感压抑和厌倦,时时有逃离城市的冲动,但习惯了繁华的我们却已经不能够再忍受生活在别处了,纯粹而简单的生活仿佛已和我们绝缘。自然美SPA     

德化陶瓷学院图书馆建筑设计随笔

德化陶瓷学院图书馆的建筑设计以突出以人为本及突出人、建筑、环境三者的和谐组合为主导思想,强调使用功能空间的优化组合及空间的深化,和建筑造型、景观环境相结合的整体设计。构筑建筑的自身魅力及良好的环境效应。