5G通信技术下的汽车无人驾驶技术之研究

信息化技术升级体系下5G通信技术逐渐走入人们的生活,物联网产业的高速进步也带动了其他领域的发展,汽车无人驾驶受到了越来越多的关注,将5G通信技术和汽车无人驾驶技术予以融合,能进一步推动行业的成长.本文简要介绍了5G通信技术和无人驾驶导航方式,并着重讨论5G通讯技术下汽车无人驾驶技术的应用.     

真空密封法测定沥青混合料毛体积相对密度试验

使用真空密封法,测定了不同碾压次数成型试件的毛体积相对密度,探讨了测定时产生误差的原因;与传统表干法以及蜡封法测定的结果进行对比分析。结果表明:真空密封状态与密封袋的材质是影响试验误差的主要因素;使用真空密封法测定的结果重复性较好,其测定值与表干法以及蜡封法测定值间有良好的线性关系,但测定值间存在显著性差异。     

论秘书的气质养成

现代社会对秘书这一职业提出了更高的要求.秘书不仅应具备多方面的基本素质,还应在实际工作中形成独特的气质特点.养成良好的气质会对秘书实际工作的开展有所裨益.     

Dynamics and interactions between spot and forward freights in the dry bulk shipping market

Analyzing the interactions between spot and forward freight agreement (FFA) prices in the dry bulk shipping is important as they play a significant role for shipping companies to secure their profits and avoid potential risks in the volatile market. By applying the vector autoregression (VAR) and the vector error correction model (VECM), this paper identifies the long-run and mutual causal relationship between the spot and FFA prices on the BPI T/C and BCI C7 routes. Along with these cointegrating rates, exogenous factors such as the market demand and supply and some economic indices are also recognized as contributing variables for the dynamic movement of the spot and FFA prices. Importantly, the mean-reverting process is justified on both routes with different mechanisms. When the spot and FFA prices deviate from their equilibrium level in the short run, they will be adjusted to their long-run equilibrium more directly and clearly on the BPI T/C route than those on the BCI C7 route. It also indicates that this adjusting power has direction and size asymmetries on both routes. In addition, the impulse analysis indicates that the spot rate is more volatile than its corresponding FFA prices confronting innovations. The results of this study provide a reference to the participants in the dry bulk shipping market on the causes of fluctuation in spot and FFA prices and their interactions, which can be used to promote the risk management in the market.     

城市轨道车辆运行中纵向冲击对人体振动影响的仿真研究

建立了人体与轨道车辆振动耦合模型,并在模型基础上进行仿真研究.从仿真结果中得到车体、人体头部及人体内脏在横向、垂向和纵向上的振动响应及其能量集中的主要频率段,并从功率谱密度图得知人体头部和内脏的振动响应频率基本相同.当冲击力越大速度越高时,车体和人体所产生的响应加速度越大,但垂向和横向的响应比较小,纵向响应比较大.     

多载波通信系统中脉冲噪声抑制技术研究

作为一种解决码间干扰的有效手段,正交频分复用技术(OFDM)已成为各种数据通信标准诸如AD-SL(DMT)、数字音频/视频广播(DAB/DVB)的核心技术,但是脉冲噪声影响仍然是限制其应用的一个重要问题。文中分析了几种DVB系统脉冲噪声抑制算法,对输入解调器前的数字信号进行非线性处理,以限制脉冲噪声的幅度。仿真表明,对输入信号中幅度较大的样值点进行限幅比置零效果更好。     

基于LGSVL/Apollo的网络延迟攻击下自动驾驶车辆定位估算

为提高网络延迟攻击下自动驾驶车辆定位估计算法的精确度,研究了延迟模型下自动驾驶车辆定位的无偏差有限脉冲响应(UFIR)估计器设计方法,并仿真实验.搭建延迟攻击下的车辆运动学模型,拓展模型至有限长度的时间窗口,推导UFIR算法按批处理式与迭代式表达形式,分析Apollo系统各功能模块的数据流动,基于LG开源自动驾驶仿真器...     

典型舱内爆炸载荷对加筋板的毁伤特性

[目的]为研究典型舱内爆炸载荷对加筋板的毁伤特性,将舱内爆炸载荷分为初始爆炸冲击波载荷和准静态气压载荷,利用有限元分析软件LS-DYNA开展爆炸载荷下固支单向加筋板毁伤特性的数值模拟.[方法]主要模拟载荷冲量相等和载荷峰值相等时固支单向加筋板的变形特性,以及加筋板分别在初始爆炸冲击波载荷、准静态气压载荷及2种载荷联合作...     

STUDY ON MAXIMUM SPECIFIC SLUDGE ACTIVITY OF DIFFERENT ANAEROBIC GRANULAR SLUDGE BY BATCH TESTS

IntroductionGranular sludge UASB (Up- flow AnaerobicSludge Bed) reactor is the most widely used anaer-obic waste water treatmentreactor in the world.Itbelongs to the second generation of modern anaero-bic reactor. EGSB(Expanded Granular SludgeBed) reactor is an even higher efficient anaerobicwastewater treatment reactor,which is developedin the past ten years based on the UASB technolo-gy.It belongs to the third generation of modernanaerobic reactor. EGSB includes two kinds oftypes:I…     

基于复合信号特征的崩塌落石监测方法

行车限界内的崩塌落石灾害监测是保障山区铁路行车安全的重点研究课题.若干基于单信号特征的监测方法已经投入应用,其固有的误报率和漏报率超出了铁路运输所能容忍的限度.考虑到崩塌落石会产生侵限目标和冲击波等多种信号特征,提出了一种基于复合信号特征的监测方法,对信号源不同的多种信号特征进行提取,同时要求这些特征必须具备高度的时空域相关性.理论分析和各山区路局的实践表明,此方法可以使监测系统的误报率和漏报率同时降低到若干数量级以下.