湖北武麻高速公路橡胶沥青路面设计与应用

通过室内试验和现场施工相结合的方法研究了橡胶沥青SMA-16和AC-20沥青混合料力学性能,提出了在中上面层之间设置橡胶沥青+单级配碎石粘接层的新方法,并对其使用效果进行了试验验证,采用BISAR软件计算了各结构层层底拉应力,据此进行了武麻高速公路橡胶沥青路面优化设计。研究结果和实体工程应用表明,橡胶沥青路面优化设计提高了抗裂性能和抗水损坏能力,并节约了工程造价。     

基于ANP方法的公交车实时调度策略选择研究

给出了公交车的4种实时调度策略,包括滞站调度、跳站调度、短掉头和发车调度.4种调度策略各有优缺点,但是在特殊环境之下,如何考虑选择不同的调度策略是管理者面临的重要问题.文中建立了ANP方法,选择12个指标对4种不同的调度策略进行对比,考虑指标与因素之间的反馈与关联,更接近于决策的实际情况,有助于提供更好的方案选择.     

串联式混合动力公交车的参数选择

根据城市公交车的工作特点,对串联式混合动力公交车动力系统主要部件发动机、电动机、电池组等,提出了选择和设计原则,实现优化匹配,提高动力性、燃油经济性以及降低排放性能.     

关于公交线路线形及对位编码的思考

把城市公交线路站点进行线性回归,将其归纳为纵线、横线、左斜线、右斜线和环(含弧)线,并对社区公交提出新的见解.同时采用了分线形按方位区间分别对位编码的方法,对普通的公交线路番号的每个代码赋予特定的含义,使其具有明确的线路走向和方位识别功能.还对“线形布线及对位编码法”在实施中可能出现的问题及应对措施提出了自己的意见.该...     

自动锁止—自由轮毂工作原理解析

简述现有四轮驱动车型接合轮毂的类型,以及自动型接合轮毂的特性及操作方法。通过分析自动轮毂结构及各零部件的功能和操作要求,阐述自动轮毂的工作原理。结合实际使用过程中各种不正常操作导致的响声,依据原理及图片直观阐述噪音产生原因。最后描述常见故障及故障排除方法,明确自动轮毂的使用方法及故障判断要点。     

再生混凝土骨料沥青混合料级配设计新方法探讨

为了解决再生混凝土骨料应用于沥青混凝土级配设计时出现的新情况、新问题,应用拉格朗日乘数法和Excel规划求解建立了适于再生混凝土骨料沥青混合料级配设计的精确计算模型及应用程序。结果表明拉格朗日乘数法是解决问题的理论基础,也是建模的核心,而Excel规划求解是对前者的改进和延伸,从而从理论与实践两方面有效地解决了该问题,并使之在工程的质量控制方面得到推广。     

N掺杂的ZnO薄膜发光性质研究

以醋酸锌为前驱体、醋酸铵为掺杂源,采用溶胶—凝胶法制备出N掺杂的ZnO薄膜,研究了其表面形貌、晶体结构和变温下的光致发光光谱,探讨了N作为受主掺杂的热力学性质。结果表明,掺杂后的薄膜是六角纤锌矿结构,光谱中表现出和N相关的受主束缚激子、自由激子—受主和施主—受主对发光现象。通过理论计算得到,N作为受主的电离能大小为0.255~0.310 eV,表明N是一种有效的浅受主,其能级上的电子在较小的能量下就能够电离。     

A selection scheme for optimum number of cooperative secondary users in spectrum sensing

An optimization scheme for choosing the optimum number of secondary users in cooperative spectrum sensing based on the cyclostationary feature detection with Neyman-Pearson criterion is proposed in this paper. The optimal soft combination test statistic for the cooperative spectrum sensing based on cyclostationary feature detection is derived according to the generalized likelihood ratio test and its corresponding detection performance is deduced. A target function, considering two important parameters as the resource use efficiency and the number of samples employed by each cooperative secondary user in the system design, is constructed to obtain the optimum number of cooperative secondary users. It can be found that the selection scheme is to make a tradeoff between the system complexity of the cognitive radio network and the global sensing performance of the cooperative spectrum sensing.     

External equality and absolute equality coincide in finite CCS and <Emphasis Type="Italic">π</Emphasis> calculus without summation

External equality and absolute equality are defined model independently by Fu. It is interesting and important to know whether these two equalities coincide or not. There are some results in Fu’s paper for this issue. It is relatively easy to prove the coincidence if the summation operator is in the language, otherwise it is harder. In fact Fu proposed it as an open problem whether the two equalities coincide in some languages without summation. In this paper, the proofs of the coincidence in finite CCS and π calculus without summation are given.     

Development and application of thermal mathematical model of iron ore pellet bed in grate

Based on the analysis of heat transfer mechanics, physical and chemical change of pellet drying and preheating process in grate, the mathematical model is established and solved by three-diagonal matrix algorithm. With Visual Basic 6.0 a simulation software is developed. The model is verified by measurements at a domestic pellet plant, and the temperature distribution of pellet bed is gained. Meanwhile, the influence of different operation parameters on the pellet thermal process is studied. The results can be taken as a basis of practical production control and the grate optimizing design.