光纤陀螺干扰信号探测

介绍了一种利用小波模极大值检测光纤陀螺干扰信号的方法。对实测的光纤陀螺干扰信号采用连续小波变换,通过分析小波变换模极大值线的特点,提出了光纤陀螺扰动信号探测的小波模极大值线方法,并进行了实验验证。结果表明：小波模极大值方法能够有效的对光纤陀螺干扰信号进行检测和定位。     

某型调距桨装置桨毂强度有限元分析研究

对某型调距桨桨毂机构进行有限元建模,在最大持续功率(MCR)工况下进行仿真分析,并把重要零件的应力与传统理论计算结果进行了分析比较.结合传统的理论计算,分析结果可为桨毂机构工程设计、结构优化提供更好的依据.     

水下清淤取样检测器具的研究与应用

基槽清淤质量目前尚无可直接采用的成熟检测方法,为解决这一难题,经过大量现场调研,结合本项目特点和以往的施工经验,研制了“封闭旋进取泥器”和“潜底定位取浆器”两项专利技术,并针对深圳机场扩建工程提出了可供实际操作的准确定量的基槽清淤检测方法,从而解决了这一工程难题。通过深圳机场扩建工程清淤质量的检测,证实该技术的可靠性,并可在类似的工程中推广应用。     

舰船复杂结构电力系统故障区域快速定位研究

本文提出了复杂结构舰船电力系统在并网条件下进行保护区域的划分,并在此基础上引入汇入电流的概念。在利用保护区域差动电流幅值特征的基础上,引入相位特征,并对舰船电力系统故障区域快速定位的问题提出了相应的解决方法。     

Determining the number and location of winter road maintenance depots – a case study of the district road network in Serbia

Determining the number and location of depots for winter road maintenance (WRM) represents one of the important strategic decisions while planning WRM activities. However, most organizations dealing with WRM make empirically based decisions. Optimizing the number and location of WRM depots has the potential to achieve considerable cost savings, improve mobility and efficiency, as well as reduce environmental impacts. This paper presents two optimization models. The first model determines the location of WRM depots by minimizing the total distance travelled by maintenance vehicles. The second model determines the optimum number and location of WRM depots by minimizing total transportation costs and capital expenditure and operational expenditure of the depots. The models are then applied to the district road network in Serbia. Results show that their application could lead to significant reductions in WRM costs.     

船用低速柴油机主轴承盖预紧实验研究

某型低速柴油机主轴承盖在设计时,采用与竖直方向倾斜的轴承盖螺栓,其目的在于:轴承盖螺栓预紧时产生的水平分力使主轴承盖两侧张开,以实现主轴承盖的自动居中定位作用.本文通过主轴承盖张紧和安装实验,验证了主轴承盖在螺栓预紧力作用下能够实现自动居中定位的作用.然后通过有限元分析,研究螺栓预紧载荷与主轴承盖变形量之间的规律,并得到主轴承盖与轴承座接触面之间的摩擦系数,对实验结果进行很好的验证和补充.     

Locating refuelling stations for alternative fuel vehicles: a review on models and applications

The recent concerns on environmental issues have expedited the technological development of alternative fuel vehicles (AFVs), but the deployment of AFVs still remains at the initial stage mainly because of the lack of refuelling facilities. Recognising this, researchers have conducted various studies, proposing a variety of approaches to strategically locating refuelling stations. This paper presents a comprehensive review of the approaches, focusing more on applications than computational issues. The review identifies two main elements of the approaches: location modelling and refuelling demand estimation. Examining how the elements were handled in refuelling location studies, this paper suggests that future refuelling location models should properly reflect the intricate and various perspectives of three major AFV stakeholders: drivers, government agencies and refuelling service providers. This study is expected to help researchers efficiently set up their refuelling location problems and identify critical factors for seeking the solutions.     

On seat capacity in traffic assignment to a transit network

Seating or standing make distinct on‐board states to a transit rider, yielding distinct discomfort costs, with potential influence on the passenger route choice onto the transit network. The paper provides a transit assignment model that captures the seating capacity and its occupancy along any transit route. The main assumptions pertain to: the seat capacity by service route, selfish user behaviour, a seat allocation process with priority rules among the riders, according to their prior state either on‐board or at boarding. To each transit leg from access to egress station is associated a set of ‘service modes’, among which the riders are assigned in a probabilistic way, conditionally on their priority status and the ratio between the available capacity and the flow of them. Thus the leg cost is a random variable, with mean value to be included in the trip disutility. Computationally efficient algorithms are provided for, respectively, loading the leg flows and evaluating the leg costs along a transit line. At the network level, a hyperpath formulation is provided for supply‐demand equilibrium, together with a property of existence and an method of successive averages equilibration algorithm. It is shown that multiple equilibria may arise. Copyright © 2010 John Wiley & Sons, Ltd.     

基于VMD和RBF的舰船管路泄漏识别和定位

针对工作环境恶劣、维护保养不便的舰船管路难以迅速定位泄漏点并对其进行损害管制,提出了一种基于VMD和RBF的舰船管路泄漏识别和定位方法。首先,对管路泄漏产生的空化现象、湍流和流体与管路的摩擦进行分析,研究影响泄漏产生激励的因素;然后,提出一种基于变分模态分解(VMD)与径向基函数(RBF)神经网络的管路泄漏识别和定位方法,通过VMD得到有效分量的中心频率和能量值分别构造特征向量,输入RBF神经网络以达到泄漏识别和定位目的;最后,模拟舰船环境,搭建泄漏管路试验平台,分析泄漏管路不同工况下的振动信号,并对RBF神经网络的诊断准确率进行验证。实测舰船管路故障信号分析表明,泄漏识别的准确率为90%,泄漏定位的准确率为87.5%。     

西江长洲水利枢纽至界首河段航道碍航分析及整治措施

针对西江航运干线长洲水利枢纽至界首河段枯水期航道碍航问题,收集近年来实测的水文和地形图资料进行研究。通过对工程河段进行水文特性和河床演变分析,得知水位普遍下降与航道冲淤变化是引起枯水期航道水深不足的主要原因,弯道横流对船舶航行安全也有影响,为此针对性提出疏浚炸礁、回填深槽、调顺航线等工程措施。平面二维水流数学模型研究结果表明,实施航道整治以后,航道水深和流态得到改善。研究思路和成果可为类似工程提供借鉴。