探讨TDCS的发展

本文简单回顾了TDCS的发展历程，提出了今后其他信息化系统建设可供参考的建议，探讨了TDCS功能的进一步扩展。     

小底坡梯形明渠临界水深的加权逼近法

用两小加权迭代法计算小底坡梯形明渠的临界水深，计算简便，而精度很高；迭代两步所得结果的相对误差为１０＾－５数量级，迭代三步为１０＾－６数量级，适用范围也较宽，能满足一般水利工程的需要。     

Dynamic pricing for managed lanes with multiple entrances and exits

Priced managed lanes are increasingly being used to better utilize the existing capacity of the roadway to relieve congestion and offer reliable travel time to road users. In this paper, we investigate the optimization problem for pricing managed lanes with multiple entrances and exits which seeks to maximize the revenue and minimize the total system travel time (TSTT) over a finite horizon. We propose a lane choice model where travelers make online decisions at each diverge point considering all routes on a managed lane network. We formulate the problem as a deterministic Markov decision process and solve it using the value function approximation (VFA) method for different initializations. We compare the performance of the toll policies predicted by the VFA method against the myopic revenue policy which maximizes the revenue only at the current timestep and two heuristic policies based on the measured densities on the managed and general purpose lanes (GPLs). We test the results on four different test networks. The primary findings from our research suggest the usefulness of the VFA method for determining dynamic tolls. The best-found objective value from the method at its termination is better than other heuristics for all test networks with average improvements in the objective ranging between 10% and 90% for revenue maximization and 0–27% for TSTT minimization. Certain VFA initializations obtain best-found toll profiles within first 5–50 iterations which warrants computational time savings. Our findings also indicate that the revenue-maximizing optimal policies follow the “jam-and-harvest” behavior where the GPLs are pushed towards congestion in the earlier time steps to generate higher revenue in the later time steps, a characteristic not observed for the policies minimizing TSTT.     

平坦海底界面上圆形平板的高频回声特性

用物理声学方法(Kirchhoff近似)结合镜像原理给出了计算界面附近目标声反射的方法.研究了泥砂类沉积物构成的平坦海底界面上不同倾斜角度的刚性圆形平板某一面在不同入射掠射角的高频回声特性.计算中考虑了圆形平板在某些倾斜角度存在的遮挡影响.结果表明,圆形平板垂直于海底界面时,在大部分掠射角范围内的目标强度最大.若要减小回波强度,则圆形平板应倾斜放置.     

美国联邦公路局路阻函数探讨

路阻函数在交通分配过程中左右着路径的选择，目前广泛采用的路阻函数是美国公路局提出的BPB函数．但在交通分配的实践过程中使用美国公路局推荐BPB参数得到的结果并不理想。论文对国内外关于BPB函数的修正模型研究进行了介绍；分析了现存BPB模型的优点与缺陷；提出了BPB函数适用情况的思考。     

基于不确定需求的电动汽车共享系统规划方法

电动汽车共享有助于解决交通拥堵和环境污染问题。为提高电动汽车共享系统效率,保 障系统的可持续性,本文考虑共享需求的不确定性,提出单向电动汽车共享系统最优配置方法。 首先,以多情景处理共享需求的不确定性,以车站和状态集计车辆和调度员,考虑需求价格弹性, 构建共享电动汽车系统配置模型。然后,针对3类共享出行需求价格弹性函数,根据需求为整数 的特点,设计基于割线的外逼策略,提出用于模型求解的外点法。最后,算例证实了考虑共享需 求不确定性的必要性,分析了共享需求方差、弹性以及需求量对共享电动汽车系统利润的影响。 研究结果表明,共享电动汽车系统利润随需求量和需求方差的增加而增加,随需求弹性绝对值的 增加而减少。     

VLOOKUP函数在学生信息管理中的应用

电子表格Excel软件作为一种功能强大的数据处理工具，在高校学生管理工作中的应用日益广泛。本文以举例分析的方式探讨Excel工作表中VLOOKUP函数在学生信息管理工作中的运用，证明使用该函数在进行不同数据库的对接和交叉引用时能显著提高工作效率。     

基于优化小波基的电力故障暂态数据压缩研究

在论述基于 辨分析的小波基构造方法和小波分解理论的基础上,针对电力故障信号富含瞬时性强、衰减快暂态成分的特点,研究了基于信号离用小波逼近品质,即离散逼近时域二范数最大的小波基优化方法。分析表明,基于优化小波基的离散小波变换对电力故障暂态数据具有较主的压缩比和较小的重构误差。     

巴尔姆流的模拟与应用

巴尔姆流是交通运输生产与控制过程中普遍存在的一种事件流; 通过对巴尔姆流的模拟, 提出了一种将排队服务系统马尔可夫化的方法; 运用该方法能科学定量地分析排队服务系统的各项运营指标; 所提出的理论在交通运输生产过程与控制的研究中有广泛的应用价值     

Re-parameterization of Bézier Curves by Square Approximation with Endpoint Constraints

In order to get an approximation with better effect of parameterization of Bozier curves, we proposed a method for arc-length parameterization and the corresponding algorithms by square approximation for the discrete even de-parameterization of the curves. This method is simple and easy to implement, and the property of the approximation has no change compared with the original curve. A quantitative criterion for estimating the effect of parameterization is also built to quantitatively characterize the parameterization effect of the algorithms. As a result, the nearly arc-length parameterized curve has a smaller relative deviation using either the algorithm with point constraint at endpoints or the algorithm with point constraint plus the first derivative constraint at endpoints. Experiments show that after re-parameterization with our algorithms, the relative deviation will have at least a 20% reduction.