带曲率补偿的带隙基准电流源的设计

简单介绍了带隙基准源的基本原理,给出了一款基于Widlar结构的带曲率补偿的带隙基准电压电流源的设计方法,通过采用TSMC₀.5μm工艺库对电路进行仿真,在-40～150℃的温度范围内,其带隙基准的输出具有12ppm/℃的温度系数,电流基准的输出具有42ppm/℃。此外,文中还对曲率补偿电路的工作原理进行了分析,并且通过仿真波形对曲率补偿的工作机制进行了讨论。     

基于一种混合的节点定位算法的研究

针对基本的DV-Hop节点定位算法会产生不良的节点和多级跳带来的累积误差以及未知节点的坐标没有进行修正等缺点,提出了一种改进的混合节点定位算法WHDV-Hop算法,改进后的算法定位误差率明显比改进前的定位误差率小,通过MATLAB软件对节点定位误差方面进行仿真验证,仿真实验结果证明该改进后的算法稳定、可靠,易于实现。与DV-Hop算法相比,定位精确度提高了4.65%,计算量减少,降低了能量消耗水平,实现预期的目标。     

基于C/S架构电动汽车数据管理系统的开发

电动汽车示范运营考核是大规模推广电动汽车的基础性工作,对相关政策的制定以及促进电动汽车的全面应用意义重大。针对电动汽车运营考核的各项参数要求,利用Visual Basic 6.0和Access数据库,开发电动汽车运营考核数据管理系统。该系统实现了电动汽车数据的收发,数据的存储﹑显示,历史数据图表的显示等功能,为电动汽车的研究开发以及运行工况分析提供了有力的帮助。     

DM-CTSA: a discriminative multi-focused and complementary temporal/spatial attention framework for action recognition

Neural Computing and Applications - Video-based human action recognition remains a challenging task. There are three main limitations: (1) Most works are only restricted to single temporal scale...     

AFDX网络协议研究

介绍了AFDX网络的产生背景及发展历程;解析了ARINC664规范各个部分的功能及与开放式系统参考模型的关系;总结了AFDX网络相对于商用以太网的特点和AFDX网络与机载系统的关系,通过对AFDX在A380等飞机上的应用研究,归纳了基于AFDX网络的航空电子系统的特点;AFDX网络已成功应用于工程实践,该网络具有完整的协议结构,具有高实时性、高确定性和高可靠性的特点,是一种新型的机载网络总线。     

五自由度上肢康复机器人动力学建模及仿真

分析了五自由度上肢康复机器人的系统结构,构建出新的系统简化模型,并利用拉格朗日动力学法建立康复机器人简化动力学方程,提出了一类机器人简化建模的新方法.在Matlab中用V-realm Builder工具建立5-DOF上肢康复机器人三维虚拟仿真模型并进行虚拟仿真.仿真结果表明,简化的动力学模型在康复机器人控制中应用效果良好,理论响应曲线与实际响应曲线误差较小.该方法建模过程简单、快捷、有效,适合现代计算技术的发展,为康复机器人系统的优化设计及运动控制提供了理论依据.     

A Polynomial Algorithm for Computing Elementary Siphons in a Class of Petri Nets

A set of elementary siphons plays a key role in the development of deadlock prevention policies for automated manufacturing systems. This paper addresses the computation problem for elementary siphons in a subclass of Petri nets which are basic systems of simple sequential processes with resources (BS³PR) and can model many automated manufacturing systems. An algorithm for enumerating elementary siphons is established by the one‐to‐one relationship between maximal perfect resource‐transition circuits (MPCs) and strict minimal siphons. A set of MPCs is first computed, followed by a set of elementary siphons in a BS³PR. The presented algorithm is proved to have polynomial‐time complexity. An example is used to illustrate the algorithm.     

Optimal Path Problems with Second-Order Stochastic Dominance Constraints

This paper studies optimal path problems integrated with the concept of second order stochastic dominance. These problems arise from applications where travelers are concerned with the trade off between the risks associated with random travel time and other travel costs. Risk-averse behavior is embedded by requiring the random travel times on the optimal paths to stochastically dominate that on a benchmark path in the second order. A general linear operating cost is introduced to combine link- and path-based costs. The latter, which is the focus of the paper, is employed to address schedule costs pertinent to late and early arrival. An equivalent integer program to the problem is constructed by transforming the stochastic dominance constraint into a finite number of linear constraints. The problem is solved using both off-the-shelf solvers and specialized algorithms based on dynamic programming (DP). Although neither approach ensures satisfactory performance for general large-scale problems, the numerical experiments indicate that the DP-based approach provides a computationally feasible option to solve medium-size instances (networks with several thousand links) when correlations among random link travel times can be ignored.     

Robust Redundancy Scheme for the Repair Process: Hierarchical Codes in the Bandwidth-Limited Systems

High performance computing can be well supported by the Grid or cloud computing systems. However, these systems have to overcome the failure risks, where data is stored in the “unreliable” storage nodes that can leave the system at any moment and the nodes’ network bandwidth is limited. In this case, the basic way to assure data reliability is to add redundancy using either replication or erasure codes. As compared to replication, erasure codes are more space efficient. Erasure codes break data into blocks, encode these blocks and distribute them into different storage nodes. When storage nodes permanently or temporarily abandon the system, new redundant blocks must be created to guarantee the data reliability, which is referred to as repair. Later when the churn nodes rejoin the system, the blocks stored in these nodes can reintegrate the data group to enhance the data reliability. For “classical” erasure codes, generating a new block requires to transmit a number of k blocks over the network, which brings lots of repair traffic, high computation complexity and high failure probability for the repair process. Then a near-optimal erasure code named Hierarchical Codes, has been proposed that can significantly reduce the repair traffic by reducing the number of nodes participating in the repair process, which is referred to as the repair degree d. To overcome the complexity of reintegration and provide an adaptive reliability for Hierarchical Codes, we refine two concepts called location and relocation, and then propose an integrated maintenance scheme for the repair process. Our experiments show that Hierarchical Code is the most robust redundancy scheme for the repair process as compared to other famous coding schemes.     

动载作用下机场刚性道面模态参数识别研究

关于机场道面刚性结构参数识别问题,研究移动荷载作用下机场刚性道面识别系统中,传统弹性、粘弹性解析识别精度的不足,建立了移动荷载作用下弹性支承边界、弹性嵌固边界和实际边界条件下的道面板的运动方程,提出了一种基于变分法、功互等定理的Kelvin粘弹性地基上道面板系统的识别方法。同时根据最小二乘法准则进行反演,拟合实测动挠度和理论动挠度,从而识别出地基反应模量K。经仿真与实测结果可知,改进方法在保证识别速度的前提下可以显著提高识别精度,具有很好的应用价值,为机场刚性道面的设计、参数识别和质量评价等提供理论依据。