采用模糊加载控制的大功率筑机传动实验台

针对目前传动实验台存在的问题，提出了一种大功率直流合流控制方案，加载方式上采用模糊控制，减少了超调，提高了加载的平滑性，节电效果明显。     

贵州省新能源汽车销售现状调查及分析

通过对贵州省各地区新能源汽车的销售情况展开调查,从而为省内新能源汽车销售提供一些理论的科学依据。本文利用调查问卷网络平台设计问卷对新能源车主、汽车4S店销售人员和汽车维修人员等进行随机调查,分析人们偏爱哪些新能源汽车品牌、购买汽车的用途和新能源汽车销售量低的障碍及政府补贴对购车的影响。结果表明:(1)根据年龄、性别及收入来给消费者设计购买新能源汽车的计划可以提高销售成功率;(2)制约销售的主要因素是新能源汽车的动力不足,续航里程差,配套设施落后及国家扶持的力度。     

A methodology for vehicle sideslip angle identification: comparison with experimental data

Sideslip angle could provide important information concerning vehicle's stability. Unfortunately direct measurement of sideslip angle requires a complex and expensive experimental set-up, which is not suitable for implementation on ordinary passenger cars; thus, this quantity has to be estimated starting from the measurements of vehicle lateral/longitudinal acceleration, speed, yaw rate and steer angle. According to the proposed methodology, sideslip angle is estimated as a weighted mean of the results provided by a kinematic formulation and those obtained through a state observer based on vehicle single-track model. Kinematical formula is considered reliable for a transient manoeuvre, while the state observer is used in nearly quasi-state condition. The basic idea of the work is to make use of the information provided by the kinematic formulation during a transient manoeuvre to update the single-track model parameters (tires cornering stiffnesses). A fuzzy-logic procedure was implemented to identify steady state or transient conditions.     

DD6120HCI大客车热力特性的实验研究

本文对大客车热力特性进行了实验研究，实验内容包括车厢气密性，客车热力特性，空调系统制冷能力以及车围结构导热性等。本文还讨论了汽车稳太热载荷及车围结构导热的计算方法。     

Hydrodynamic damping of a circular cylinder at low KC: Experiments and an associated model

This paper investigates the hydrodynamic damping of a smooth circular cylinder undergoing forced oscillations at Keulegan-Carpenter (KC) numbers smaller than 5 and Reynolds (Re) numbers from 10³–10⁵ with and without background steady currents. A series of experiments are conducted with a circular cylinder oscillating in still water, in-line currents and cross currents. The measured drag coefficients of the smooth cylinder in the still water condition match with the well-published results and the theoretical solution of Stokes and Wang at very small KC numbers. The hydrodynamic damping increases with the in-line steady current whereas it remains almost constant at small transverse velocities and increases notably when the latter becomes large. To predict the hydrodynamic damping in in-line steady currents, the performance of the Morison equation based on relative velocity and independent velocity is explored, respectively. The latter model, by separating the drag into two independent parts, leads to a better fit of the drag force than the former, which is not surprising. However, the former is still a preferable option for engineering design due to its simplicity. The experimental data suggest that the existing design guidelines such as ISO-19902 or DNVGL-RP-C205 should be used with caution for KC < 5.     

A Stated preference freight mode choice model

Transport policy aims to assist the transport system to work more efficiently and effectively. An understanding of the reasons why people choose to move freight in a certain manner is critical to the development of appropriate policies. This article outlines a data collection approach and the development of a disaggregate mode choice model applicable to the analysis of freight shipper decision making. It focuses on the choice between rail and road in Java, Indonesia. The model indicates that safety, reliability and responsiveness are major attributes influencing rail/road freight mode choice. Transport policies aimed at improving these dimensions should increase the attractiveness of rail transport.     

复杂地应力红层泥岩隧道持续底鼓原因分析北大核心CSCD

为揭示复杂地应力红层泥岩隧道持续底鼓特征及底鼓原因,以某隧道为研究对象,通过长期变形监测、地下水位监测、隧底围岩位移监测等方法对底鼓变形特征进行了统计分析,并结合钻孔取芯岩样分析、地应力测试、围岩膨胀力测试、岩石蠕变试验、数值模拟分析等手段对可能导致隧道底鼓的因素逐一进行了分析。结果表明:受控于近水平层状泥岩以及复杂地应力,隧道部分段落呈现出底鼓时间“不收敛”、底鼓段落“不连续”、底鼓程度“不均衡”的三大特征;隧道岩层产状近水平,岩性为粉砂质泥岩,属于软质岩,未达到膨胀岩判定标准,具有中—低蠕变特性,隧址区地应力场以水平构造应力为主,水平应力在9.5~13.73 MPa之间;隧道开挖后,局部应力集中导致围岩发生蠕变,当蠕变产生的形变压力过大时,仰拱局部进入塑性状态,隧道即产生底鼓。     

小型船用柴油机排放控制的措施研究

以Z6150ZLCZ-5型船用柴油机为分析了对象,分析了供油提前角、启喷压力、海水温度等对柴油机排放、油耗的影响,在此基础上对原有机型进行了改进。通过对改进机型进行排放测试,证明各方面的改进取得了预期的效果。该试验研究为船用柴油机满足排放控制的要求拓宽了思路,为该机型的进一步改进提供了可靠依据。     

Experimental and Finite Element Analysis for Multi-lead Rubber Bearings： A Comparative Study

The mechanical properties of multi-lead rubber bearings (MLRBs) were investigated by experiment and finite element analysis. First, the vertical stiffness, horizontal stiffness and yielded shear force were tested for four MLRB specimens and two specimens of the single-lead rubber bearings (SLRBs). Then, the MLRBs were modeled by the explicit finite element analysis software ANSYS/LS-DYNA, in order to evaluate the horizontal force-displacement hysteretic curves under static vertical and dynamical horizontal loadings. The disagreement between the tested and theoretical values was less than 11.4%, and MLRBs and SLRBs were similar in vertical stiffness, pre-yield stiffness and yield stiffness.     

软基处理加固效果的试验研究及相关问题的处理

根据采用堆载预压、真空排水预压、预应力管桩、CFG桩、联合桩不同处理方式对深厚软土的加固试验,基于对现场试验测试数据的整理分析和加固前后原位测试及土工试验数据的对比研究,对加固效果初步分析,提出在实施阶段中的建议及一些问题的处理方法。