遗传算法优化的模糊神经网络在故障诊断中的应用

本文针对船舶柴油机故障诊断系统提出了一种基于遗传算法优化训练的模糊神经网络诊断方法,介绍了这种模糊神经网络故障诊断系统的结构及其参数形式,通过遗传优化算法对它的权值和阈值进行了学习优化训练。这种方法可以有效地避免通常所选BP算法训练易陷于局部极值的问题,最后将该遗传算法优化训练的模糊神经网络系统应用到船舶柴油机的故障诊断中,通过仿真研究,说明了该方法的有效性。     

天然气烤漆室风机变频节能技术改造

简要介绍利用燃烧机信号控制变频器调整风机输出功率,在满足工艺要求的同时实现节能。     

预应力混凝土变宽箱梁偏载系数研究

介绍了单箱多室变宽箱梁在偏心荷载作用下的力学行为、偏载系数简化计算的原理和简化计算方法.并通过工程实例,将各种方法的计算结果与空间有限元法计算结果进行比较,最后推荐了在设计过程中应采用的较合理的计算方法.     

An Investigation into Regenerative Braking Control Strategy for Hybrid Electric Vehicle

Energy regeneration during braking is an important technique for hybrid electric vehicle （HEV） to improve their fuel economy and extend their driving range. Due to the effect of regenerative braking torque which is added by electric motor, the braking torque distribution between front and rear axles should be changed and the control logic of anti-lock braking system （ABS） ought to be adjusted according to the regenerative braking torque. This paper put forward a braking control strategy for hybrid electric vehicle; the control strategy is implemented with eight DOFs （Degree-of-Freedom） nonlinear vehicle forward simulation model which is built under the environment of Matlab/Simulink. Based on target wheel slip ratio, a fuzzy logic approach was applied to maintain the optimal target slip ratio so that best compromise between hydraulic torque and regenerative torque can be obtained for the vehicle.     

基于PXI和虚拟仪器的汽车发动机电控单元测试系统

论述了基于PXI总线和虚拟仪器的自动化测试系统的实现方案,采用标准的数据采集卡、DMM卡、模拟输入输出（AIO）卡以及专门设计的信号调理电路等资源组成了测试系统的硬件系统．本文自动测试系统的软件开发采用了虚拟仪器软件平台上最流行的LabVIEW,LabVIEW开发的特点是软件结构简单、容易上手,广泛为各行业的工程师所使用．由于整个发动机电控单元的测试项目很多,并且需要进行多个产品的并行测试,因此本文外选用了TestStand作为测试执行管理软件．实验运行表明,本系统运行稳定,测试结果可靠．     

A vehicle traveling time prediction method based on grey theory and linear regression analysis

Vehicle traveling time prediction is an important part of the research of intelligent transportation system. By now, there have been various kinds of methods for vehicle traveling time prediction. But few consider both aspects of time and space. In this paper, a vehicle traveling time prediction method based on grey theory (GT) and linear regression analysis (LRA) is presented. In aspects of time, we use the history data sequence of bus speed on a certain road to predict the future bus speed on that road by GT. And in aspects of space, we calculate the traffic affecting factors between various roads by LRA. Using these factors we can predict the vehicle's speed at the lower road if the vehicle's speed at the current road is known. Finally we use time factor and space factor as the weighting factors of the two results predicted by GT and LRA respectively to find the fina0l result, thus calculating the vehicle's travehng time. The method also considers such factors as dwell time, thus making the prediction more accurate.     

浅谈高速公路限速问题

针对高速公路普遍存在的超速行驶现象,通过简要分析超速行驶原因,以及速度对交通事故和成本、时间、安全效益的影响,从而为高速公路确定一个科学的限速数据,这对于高速公路使用者和我国汽车产业发展具有重要的意义。     

平陆运河牛江河下底河入汇方案研究*

支流与干流的交汇区水流流态复杂,而人工开挖运河存在交角大、汇入流量大的特点,对航道通航影响显著,需对支流口实施河道治理工程。针对平陆运河中牛江河、下底河支流汇入运河后入汇河段的干流通航问题,进行入汇河段水流运动特性的研究。基于RNG k - ε紊流模型,采用三维数值模拟方法模拟不同设计工况下支流入汇情况,结果表明原设计方案不满足通航条件。因此,在设计方案基础上提出调整入汇方向、扩大入汇断面的优化措施,显著改善了通航水流条件,达到规范要求。研究成果可为类似工程提供借鉴。     

单相感应子发电机电压控制研究

单相感应子发电机广泛地应用于舰船的中频电源系统中,其输出电压受电网电压和负载影响较大。通过分析感应子发电机的工作原理,采用PI调节和脉宽调整技术相结合的方法来调整其励磁电流,从而使其输出电压稳定。试验验证了这一技术的可行性。