郊区自驾游旅游交通指引标志设置研究

当前旅游交通指引标志设置中存在缺乏区域系统考虑、设置分散、旅游信息过于集中等问题,导致自驾游出行者难以及时、准确、连续地获得指引信息。针对这一问题,从郊区自驾游出行者的需求出发,构建区域入口、区域内部、景区附近的旅游交通三级指引系统。重点探讨二级指引标志的设计原则与方法,提出在景区重要度分类和道路节点重要度分级的基础上,确定各景区指引范围和各道路节点指引容量,对旅游交通指引标志进行选址。最后以河北省平山县为例,对提出的旅游交通指引标志设置方法进行实证研究。     

Method to simplify ship outfitting and offshore plant equipment three-dimensional (3-D) computer-aided design (CAD) data for construction of an equipment catalog

The construction of an equipment catalog is necessary in ship outfitting and offshore plant design. We investigated the present status of equipment catalogs in shipyards and revealed several requirements for the catalogs, which are manually created and time-consuming. We defined the requirements by analyzing the construction procedure of the equipment catalog and conducted interviews with shipyard employees. In addition, problems with conventional equipment catalog construction are described, and a new procedure for the construction of an equipment catalog is introduced. By analyzing shipyard requirements, criteria for simplification (including volume, ports, and the outer boundary) are defined. Further analysis of technological factors for simplification is performed, and the results of implementing the simplification system are described. The proposed system is verified using three test cases used on site.     

路用建筑垃圾击实特征试验分析

对不同配比的建筑垃圾进行重型击实试验,得到了每种配合料的最佳含水率和最大干密度曲线图,结果表明建筑垃圾的配比对最佳含水率、最大干密度影响明显。另外,通过对击实后的建筑垃圾配合料分上、中、下三层进行筛分,得到每层配合料的筛分曲线图,并且求得各层配合料的不均匀系数Cu、曲率系数Cc等。通过三层材料的筛分数据对比可知建筑垃圾材料在击实作用下各层的粒径差异,对比建筑垃圾材料击实前与击实后的粒径差异,可以清楚的得到建筑垃圾在受到击实作用后颗粒粒径的变化特征。     

Development of engine control using the in-cylinder pressure signal in a high speed direct injection diesel engine

Emission regulations are becoming more stringent and remain a principal issue for vehicle manufacturers. Many engine subsystems and control technologies have been introduced to meet the demands of these regulations. For diesel engines, combustion control is one of the most effective approaches for reducing not only engine exhaust emissions but also cylinder-by-cylinder variation. However, the high cost of pressure sensors and the complex engine head design for additional equipment present difficulties for manufacturers. In this paper, cylinder pressure-based engine control logic is introduced for a multi-cylinder high speed direct injection (HSDI) diesel engine. The time for 50% of the mass fraction to be burned (MFB50) and the IMEP are valuable for determining the combustion status. These two in-cylinder quantities are measured and applied to the engine control logic. Fuel injection timing is controlled to adjust the operating MFB50 to the target MFB50 using PID control logic, and the fuel injection quantity is controlled to adjust the measured IMEP to the desired IMEP. The control logic is demonstrated at steady state and during transient conditions and is applied to an NEDC mode test.     

超高韧性水泥基复合材料在隧道二次衬砌中的应用分析

超高韧性水泥基复合材料(UHTCC)以其良好的延性和多裂缝稳态开展性能,近年来受到工程界的青睐。通过建立模拟隧道空间开挖的二维有限元模型,对由UHTCC和普通混凝土构成的二次衬砌的内力、安全系数以及洞周位移等进行了对比分析,研究了二次衬砌厚度变化对其安全系数和结构稳定性的影响。计算结果表明,二次衬砌结构的安全系数随衬砌截面厚度呈非线性增加,由于UHTCC具有低刚度、高韧性的特点,在同等条件下,UHTCC材料的二衬支护结构的安全系数较普通混凝土材料提高2～3倍。     

轿车天窗自动开启装置的设计

装置的设计方案涉及轿车天窗控制领域,公开了一种轿车天窗自动开启的装置,其组成部分包括:天窗的控制器,用于监测车外环境温度值的车外温度传感器,用于监测车内环境温度值的车内温度传感器,用于监测车外是否下雨的雨量传感器,用于监测车辆空调器开启信号的空调信号采集装置,用于监测数据的分析对比和发送天窗装置开启/关闭信号的微处理器,控制天窗装置驱动机构工作的电磁开关。装置能够根据车内外温度、是否下雨等条件对天窗的开启进行自动调节,实现对车内温度的调节,克服了现有技术人工控制繁琐的弊端,具有结构合理,自动化程度高,运转可靠等特点,适用配有电动窗的轿车。     

钢塑一体轻量化车身结构设计研究

为实现结构优化和材料替换的混合结构设计,提出钢塑一体轻量化车身结构。以一简单试件验证了钢塑一体结构的可行性;根据灵敏度结果,在普通钣金结构车身的基础上构建了钢塑一体车身结构并对其进行尺寸优化。优化结果表明,钢塑一体车身结构在总质量降低51 kg的基础上,其静、动态特性均有不同程度的改善。最后,通过发动机罩总成试验验证了钢塑一体车身结构的轻量化优势。     

某船主推进系统建模与仿真

实船航行试验的问题是耗费高、周期长.通过构建某船用柴油机推进系统模型,包括柴油机、调速器、液力偶合器、螺旋桨及船体运动模型,在Matlab/Simulink环境下对该船的加速过程和紧急停船过程进行仿真研究.经分析对比船体在不同机桨联控策略下的运动情况,得出加速和停船过程中最佳的机桨匹配策略,为航行试验提供了理论依据.     

界面材料参数和层间状态对钢桥面铺装体系受力的影响

借助有限元数值分析方法,分析了界面材料的弹性模量和界面层厚度变化对铺装体系受力的影响及不同层间接触状态下钢桥面铺装体系受力规律,论证了钢桥面铺装中界面黏结的重要性,对于界面层材料设计和施工具有重要的指导意义。