Energy consumption and cost-benefit analysis of hybrid and electric city buses

This paper presents a cost-benefit analysis (CBA) of hybrid and electric city buses in fleet operation. The analysis is founded on an energy consumption analysis, which is carried out on the basis of extensive simulations in different bus routes. A conventional diesel city bus is used as a reference for the CBA. Five different full size hybrid and electric city bus configurations were considered in this study; two parallel and two series hybrid buses, and one electric city bus. Overall, the simulation results indicate that plug-in hybrid and electric city buses have the best potential to reduce energy consumption and emissions. The capital and energy storage system costs of city buses are the most critical factors for improving the cost-efficiency of these alternative city bus configurations. Furthermore, the operation schedule and route planning are important to take into account when selecting hybrid and electric city buses for fleet operation.     

基于专家控制系统的育苗大棚设计

基于专家控制系统的育苗大棚,以STC15F2K60S2系列单片机为核心处理器,采用包括总线拓扑结构、GSM短信报警、触屏监控、专家控制系统和网络远程监控等技术手段进行设计.详细阐述了系统整体设计,各子系统设计和育苗大棚专家系统设计.提供用户操作和控制的平台,同时完成与专家系统动态数据的交互.下位机完成环境参数的数据采集和接收监控平台控制指令操作执行机构.专家系统作为一种控制算法,通过用户输入幼苗生长状态及大棚实时环境参数作为依据,将理想环境参数作为控制目标,对育苗大棚进行智能控制.该系统解决了目前智能温室大棚控制成本高、操作复杂、故障处理困难和无法远程监控等问题.     

Reduction of capacity and projected costs associated with seat belt installation on school buses

This study examines the potential effects the installation of seat belts on school buses would have on the fleet capacity in Alabama and the resulting cost implications. The study also documents the myriad research studies and professional opinions offered on the potential safety effects of equipping school buses with safety restraints/seat belts. Four seat configurations for the school buses were analyzed. The first configuration represents the most common current bus seating configuration without seat belts, 3 seats on each side of the aisle and 12 rows (3/3-12). The physical space required for seat belt hardware may result in a loss of a row of seats and may reduce the number of students seated per row. Thus, three more configurations were studied: loss of a row of seats (3/3-11), loss of one seat per row (3/2-12), and loss of both a row of seats and a seat per row (3/2-11). The capacity for each configuration for each bus using current pupil loads was determined. The costs associated with installation of seat belts, and purchase and operation of new buses were obtained. Should school bus seat belts become mandatory in Alabama, the results obtained in this study can be used by any school system to determine the optimum configuration for their pupils, which will identify the number of additional buses that must be purchased by the school system. This study found that many of the buses that would become overloaded due to seat belt installation and the resultant loss of seating will be carrying only a few excess pupils. Transportation supervisors may be able to handle such overloads by transferring these pupils to other buses or by adjusting their bus routes to minimize purchase of new buses. Additional suggestions for handling bus overloads were offered in the body of this report.     

客车品牌整合营销传播中的项目管理应用研究

将项目管理的思想引入到客车行业的品牌整合营销传播之中,重点分析研究客车品牌整合传播中的进度控制和成本管理,以提高客车品牌营销的管理水平和传播效果。     

Locating charging infrastructure for electric buses in Stockholm

Charging infrastructure requirements are being largely debated in the context of urban energy planning for transport electrification. As electric vehicles are gaining momentum, the issue of locating and securing the availability, efficiency and effectiveness of charging infrastructure becomes a complex question that needs to be addressed. This paper presents the structure and application of a model developed for optimizing the distribution of charging infrastructure for electric buses in the urban context, and tests the model for the bus network of Stockholm. The major public bus transport hubs connecting to the train and subway system show the highest concentration of locations chosen by the model for charging station installation. The costs estimated are within an expected range when comparing to the annual bus public transport costs in Stockholm. The model could be adapted for various urban contexts to promptly assist in the transition to fossil-free bus transport. The total costs for the operation of a partially electrified bus system in both optimization cases considered (cost and energy) differ only marginally from the costs for a 100% biodiesel system. This indicates that lower fuel costs for electric buses can balance the high investment costs incurred in building charging infrastructure, while achieving a reduction of up to 51% in emissions and up to 34% in energy use in the bus fleet.     

Data Fusion-Based Traffic Density Estimation and Prediction

Traffic congestion has become a major challenge in recent years in many countries of the world. One way to alleviate congestion is to manage the traffic efficiently by applying intelligent transportation systems (ITS). One set of ITS technologies helps in diverting vehicles from congested parts of the network to alternate routes having less congestion. Congestion is often measured by traffic density, which is the number of vehicles per unit stretch of the roadway. Density, being a spatial characteristic, is difficult to measure in the field. Also, the general approach of estimating density from location-based measures may not capture the spatial variation in density. To capture the spatial variation better, density can be estimated using both location-based and spatial data sources using a data fusion approach. The present study uses a Kalman filter to fuse spatial and location-based data for the estimation of traffic density. Subsequently, the estimated data are utilized for predicting density to future time intervals using a time-series regression model. The models were estimated and validated using both field and simulated data. Both estimation and prediction models performed well, despite the challenges arising from heterogeneous traffic flow conditions prevalent in India.     

构建安全的铁路信息网络问题与对策

从网络设备、路由规划、用户隔离、防攻击、信息加密、终端安全等方面对铁路信息网络面临的各种安全问题进行了探讨。针对这些问题,作者结合实际工作提出了相应的解决方案。     

某客车底架结构局部优化设计研究

以底架局部为研究对象,抽取有代表性的局部结构建立有限元模型,提出多个改进方案;通过对比各改进方案,得到综合效果较好的优化结构。该方法在结构优化设计中简单、高效。     

CAN总线在列控地面系统中的应用和设计

本文阐述了列控地面系统中的CAN总线网络硬件设计以及为满足铁路信号的故障一安全而对CAN总线进行的故障一安全设计。     

武汉市快速公交系统适应性研究

快速公交系统(BRT)作为一种经济、高效的大容量公共交通模式,是当前优化城市交通方式的一种新理念。应用宏观和微观相结合的分析方法,从武汉市宏观环境和实际条件出发,探讨了武汉市BRT系统的适应性。