燃油经济模式的蓄电池电压控制系统研究

铅酸蓄电池通过化学能和电能的转换,能够为车辆储存电能和释放电能。如果蓄电池电量充足,在进入燃油经济模式后,可以通过控制蓄电池工作电压,使其放电为用电器供电,减少燃油消耗。本文在分析蓄电池工作原理和燃油经济模式特点的基础上,研究了基于反馈控制的蓄电池电压控制系统,设计了最优充电电压控制算法,并通过车辆在燃油经济模式的试验进行验证,进而优化参数设计,使系统和算法更加合理和稳健。     

隧道光面爆破护壁装药结构数值模拟分析

利用仿真软件,分别对PVC管与聚氨酯泡沫新型护壁结构的不耦合装药和耦合装药2种工况的炮孔爆破过程进行了数值模拟分析。结果表明:耦合装药结构爆破过程中,炮孔周边单元测点应力的变化规律与不耦合装药结构大致相同;该新型护壁结构对爆炸应力波具有衰减作用,可延长爆炸应力波的传播时间;炸药爆炸时高温高压使聚氨酯泡沫材料产生形变,消耗掉部分爆炸能量,导致传播到空气和岩体上的应力峰值衰减47.02%~53.78%。     

A bi-level model for GHG emission charge based on a continuous distribution of travelers’ value of time (VOT)

Transportation is an important source of greenhouse gas (GHG) emissions. In this paper, we develop a bi-level model for GHG emission charge based on continuous distribution of the value of time (VOT) for travelers. In the bi-level model framework, a policy maker (as the leader) seeks an optimal emission charge scheme, with tolls differentiated across travel modes (e.g., bus, motorcycles, and cars), to achieve a given GHG reduction target by shifting the proportions of travelers taking different modes. In response, travelers (as followers) will adjust their travel modes to minimize their total travel cost. The resulting mode shift, hence the outcome of the emission charge policy, depends on travelers’ VOT distribution. For the solution of the bi-level model, we integrate a differential evolution algorithm for the upper level and the “all or nothing” traffic assignment for the lower level. Numerical results from our analysis suggest important policy implications: (1) in setting the optimal GHG emission charge scheme for the design of transportation GHG emission reduction targets, policy makers need to be equipped with rigorous understanding of travelers’ VOT distribution and the tradeoffs between emission reduction and system efficiency; and (2) the optimal emission charge scheme in a city depends significantly on the average value of travelers’ VOT distribution—the optimal emission charge can be designed and implemented in consistency with rational travel flows. Further sensitivity analysis considering various GHG reduction targets and different VOT distributions indicate that plausible emission toll schemes that encourage travelers to choose greener transportation modes can be explored as an efficient policy instrument for both transportation network performance improvement and GHG reduction.     

Understanding public response to a congestion charge: A random-effects ordered logit approach

Public acceptance is consistently listed as having an enormous impact on the implementation and success of a congestion charge scheme. This paper investigates public acceptance of such a scheme in Australia. Surveys were conducted in Brisbane and Melbourne, the two fastest growing Australian cities. Using an ordered logit modeling approach, the survey data including stated preferences were analyzed to pinpoint the important factors influencing people’s attitudes to a congestion charge and, in turn, to their transport mode choices. To accommodate the nature of, and to account for the resulting heterogeneity of the panel data, random effects were considered in the models. As expected, this study found that the amount of the congestion charge and the financial benefits of implementing it have a significant influence on respondents’ support for the charge and on the likelihood of their taking a bus to city areas. However, respondents’ current primary transport mode for travelling to the city areas has a more pronounced impact. Meanwhile, respondents’ perceptions of the congestion charge’s role in protecting the environment by reducing vehicle emissions, and of the extent to which the charge would mean that they travelled less frequently to the city for shopping or entertainment, also have a significant impact on their level of support for its implementation. We also found and explained notable differences across two cities. Finally, findings from this study have been fully discussed in relation to the literature.     

盘锦市普通公路工程招标投标报价策略研究

本文分析了盘锦市普通公路工程造价构成的特点,提出了投标报价的可行策略,为投标单位确定有竞争力的投标报价提供了指导意见。     

浅谈高速公路联网收费管理

从正、反两方面论述高速公路实施联网收费的必要性 ,以及进行高速公路联网收费管理的一些建议和规划的探讨     

风火山隧道光面爆破盐水不耦合装药结构试验研究

研究目的:针对青藏铁路风火山冻土隧道特殊地质条件和气候条件,研究隧道内气温高容易引起隧道围岩融塌的问题。研究方法:理论分析引起隧道工作面温度升高的原因,针对盐水-空气复合不耦合装药结构,进行理论与模拟试验研究。研究结论:爆生气体是影响冻土热平衡的主要热源之一;盐水介质对爆生气体的降温效果十分显著,高达70%;采用NaCl盐水水炮泥封堵炮孔的技术措施,可达到降低工作面温度和有效降尘的目的;采用复合不耦合装药结构可以有效降低爆破对围岩的损伤。     

计重收费在道路管理中的应用

超载超限运输是困扰我国公路交通发展的严重问题之一,引发了交通、流通、汽车制造等领域的一系列问题,干扰了国家经济的健康发展,需综合治理。阐述了我国公路超载超限运输的危害,分析其产生的原因和实施计重收费的理论依据,重点讨论了道路管理中采用计重收费的优劣,得知计重收费是治理超载超限的有效方法,最后提出改进建议。     

有机锂皂石的膨胀性能影响规律的研究

从锂皂石原矿中提纯出精矿,经不同浓度的稀盐酸处理得到层电荷数逐渐降低的锂皂石样品,然后对其进行钠化,再与十六烷基三甲基溴化铵(CTAB)反应从而制得有机锂皂石.有机锂皂石在硝基苯中的黏度和红外光谱分析表明当盐酸浓度为0.2 moL· L-1时,锂皂石的层状结构几乎保持不变,此时层电荷数降低到了黏度最大的临界点.有机化最...     

高速客运专线基本电费交纳方式的探讨

客运专线供电系统设计以满足高峰小时供电确定变压器安装容量,但在运营初期,由于行车密度及运量关系,负荷率低,最大需量小。主要对两部制电价的两种基本电费交纳方式进行分析,提出适合我国国情的高速客运专线的基本电费交纳方式。