含水率对路用水泥混凝土的影响及微波在线测湿系统

在讨论了含水率对路用土质量的影响因素后，通过对不同种类测试器的分析，确定了较为适用的微波传感器，并给出了微波传感器的输出电压与集料含水率之间的关系式，进而对测试准确度进行计算。     

茅草街大桥368 m跨钢管拱肋制作与安装工艺介绍

介绍了茅草街大桥368m大跨径钢管拱肋制作、安装工艺.     

帕萨特B5轿车电路--发动机控制系统(续完)

2发动机故障码及其故障码的读取和删除 在发动机控制单元J220内配备了故障存储器，当系统或元件发生故障时，能将故障按相应的故障类型存入故障存储器。用大众汽车专用的故障阅读仪V．A．G1551或车辆系统测试仪V．A．G1552或汽车诊断测试和信息系统V．A．S5051可以读取和删除故障码。下面以故障阅读仪V．A．G1551为例，说明故障码的读取和删除程序。     

帕萨特B5轿车电路-自动变速器控制系统(Ⅰ)

在帕萨特B5轿车布线图的基础上改画成该车电路原理图——自动变速器控制系统,并介绍该系统的主要功能,自动变速器故障码及其读取方法,自动变速器测量数据块及其读取方法。     

老化因素对沥青性能的影响

通过SHRP试验，分析沥青在老化过程中，各因素(时间、温度、氧、水)对其高、低温性能的影响，从而为沥青的再生提供依据。     

Study on dynamic characteristics of vehicle gearbox under multi-boundary conditions

With the development of vehicle gearbox to high-power-density and high-speed, how to predict and optimize the dynamic characteristics of vehicle gearbox becomes increasingly prominent. Aiming at the vehicle gearbox, this paper comprehensively and deeply studies the dynamic characteristics under the multi-boundary conditions. The generation mechanism of the multi-source excitations triggering the gearbox vibration is analyzed firstly. The vibration transfer path of the gearbox is explored. Secondly, the engine excitation, the gear meshing excitation and the bearing support load are numerically calculated. According to the finite element method, a fluid-solid coupling finite element model of the gearbox body is established to predict the gearbox dynamic responses based on the Galerkin method and the Hamiltonian variational principle. Finally, the effects of the excitation condition, oil height and reinforcement forms on the vibration responses of the gearbox body are thoroughly studied by simulation. The analysis indicates that it not only helps to modify and improve the method of forecasting the gearbox dynamic response, and also provides the theoretical and technical guidance for the gearbox design and optimization.     

Target priority determination methods by interval-valued intuitionistic fuzzy sets with unknown attribute weights

The paper aims at the problem of multi-targets threat degree being hard to be evaluated accurately in complex air defense battlefield environments. Combined with multi-sensors information fusion and interval-valued intuitionistic fuzzy sets (IVIFS) theories, the target priority determination is studied. The score and accuracy functions of IVIFS are improved with thinking about the hesitating information in order to increase the rationality. Then, the influence factors of target priority and the nonlinear relationship between the influence factors and target priority are analyzed. Next, the algorithms for calculating the factor weights and sensor weights are given. Based on the theory of IVIFS and technique for order preference by similarity to an ideal solution (TOPSIS), two methods of target priority determination based on the IVIFS and TOPSIS are proposed. At last, an application example verifies the effectiveness and flexibility of the proposed algorithms.     

Exploring the impact of walk–bike infrastructure,safety perception,and built-environment on active transportation mode choice: a random parameter model using New York City commuter data

This study estimates a random parameter (mixed) logit model for active transportation (walk and bicycle) choices for work trips in the New York City (using 2010–2011 Regional Household Travel Survey Data). We explored the effects of traffic safety, walk–bike network facilities, and land use attributes on walk and bicycle mode choice decision in the New York City for home-to-work commute. Applying the flexible econometric structure of random parameter models, we capture the heterogeneity in the decision making process and simulate scenarios considering improvement in walk–bike infrastructure such as sidewalk width and length of bike lane. Our results indicate that increasing sidewalk width, total length of bike lane, and proportion of protected bike lane will increase the likelihood of more people taking active transportation mode This suggests that the local authorities and planning agencies to invest more on building and maintaining the infrastructure for pedestrians. Further, improvement in traffic safety by reducing traffic crashes involving pedestrians and bicyclists, will increase the likelihood of taking active transportation modes. Our results also show positive correlation between number of non-motorized trips by the other family members and the likelihood to choose active transportation mode. The model would be an essential tool to estimate the impact of improving traffic safety and walk–bike infrastructure which will assist in investment decision making.     

Tool for Predicting the Ultimate Bending Moment of Ship and Ship-Shaped Hull Girders

The present paper presents a historical review associated with the research works on hull girder strength of ship and ship-shaped structures. Then, a new program is developed to determine the ultimate vertical bending moment of hull girder by applying direct method, stress distribution method, and progressive collapse analysis method. Six ships and ship-shaped structures used in the benchmark study of International Ship and Offshore Structures Congress (ISSC) in 2012 are adopted as examples. The calculation results by applying the developed program are analyzed and compared with the existing results. Finally, the roles of the developed program and its further development are discussed.     

A Simplified Model for the Effect of Weld-Induced Residual Stresses on the Axial Ultimate Strength of Stiffened Plates

The present work investigates the compressive axial ultimate strength of fillet-welded steel-plated ship structures subjected to uniaxial compression, in which the residual stresses in the welded plates are calculated by a thermo-elasto-plastic finite element analysis that is used to fit an idealized model of residual stress distribution. The numerical results of ultimate strength based on the simplified model of residual stress show good agreement with those of various methods including the International Association of Classification Societies (IACS) Common Structural Rules (CSR), leading to the conclusion that the simplified model can be effectively used to represent the distribution of residual stresses in steel-plated structures in a wide range of engineering applications. It is concluded that the widths of the tension zones in the welded plates have a quasi-linear behavior with respect to the plate slenderness. The effect of residual stress on the axial strength of the stiffened plate is analyzed and discussed.