城市公交车辆底盘集中润滑系统的应用与维护

<正>城市公交车辆底盘集中润滑系统可以定时定量润滑,降低城市公交车辆的维修费用,减少过量油脂对环境的污染,延长车辆寿命,提高车辆操控的舒适性和安全性。1城市公交车辆底盘集中润滑系统结构与工作原理城市公交车辆底盘集中润滑系统主要由电动润滑泵、分配器、连接管路、车载程控器等组成。电动润滑泵的主要功能是存储润滑脂,并将润滑脂输送到各润滑点;分配器的主要功能是保证各润滑点都能得到充足的润滑     

图象处理在脉冲加热红外热成像定量检测中的应用

在红外热图象的分析研究中，由于噪声和热扩散效应，引起图象模糊物边缘扩散，影响了图象的进一步分析和面积大小的确定。     

BP神经网络在铁路运量预测模型中的应用

将神经网络中的BP算法应用到货运运量预测方面,对铁路货运运量进行了预测,并对该模型在预测时产生的误差进行了分析.目的在于提高铁路货运运量预测能力,实现铁路货运的合理运输.     

Assessment of levator hiatus by 3D ultrasound volume contrast imaging in normal nulliparas

The ability of 3D ultrasound volume contrast imaging in C-plane (VCI-C) in the assessment of female levator hiatus was analyzed in eighty normal nulliparas. Interoperator variability in levator hiatus measurements was analyzed. The comparison of the axial image of magnetic resonance imaging (MRI) and C-plane image of volume contrast imaging (VCI) in thirty normal nulliparas was also done. It shows that VCI-C can clearly demonstrate the structure and accurately quantitates the size of the levator hiatus. It is reliable, convenient and without contraindication in assessment of female levator hiatus. The technology opens up entirely new modality for assessing female pelvic floor. Foundation item: the Scientific Research Project of Shanghai Municipal Health Bureau (No. 2008083)     

山区双车道公路事故预测模型研究及在安全性评价中的应用

根据采集的双车道公路的事故、线形、交通等数据,考虑公路横向干扰、路侧情况等,将双车道公路划分为普通路段、村庄路段和交叉口,分别建立了事故总数、一般以上事故次数以及碰撞、追尾和路侧等不同形态的事故次数与道路和交通要素关系的双车道公路事故预测基础模型.然后,应用统计分析方法进行了路基宽度等事故修正因子(AMF)的研究;使用基础模型经过AMF修正、经验贝叶斯过程(EB过程)、标定等进行双车道公路机体事故预测.最后,介绍了双车道公路事故预测模型在安全性评价中的应用.     

水泥砂浆的塑性收缩定量研究

采用自行设计的水泥砂浆塑性收缩量测量装置,通过对掺加不同引气剂(ZY—99、AE2、BT—4006)、不同配比的水泥砂浆,进行正交试验研究,分析了水灰比、含气量和粉煤灰掺量对水泥砂浆塑性收缩的定量影响,讨论了水泥砂浆塑性收缩的变化机理。     

基于瞬态冲击响应的混凝土路面板脱空识别

为开发混凝土路面板脱空检测专用仪器,降低检测费用和简化检测方法,在现有脱空检测方法的基础上,根据脱空板振动频率及在定量冲击激励下振幅的变化规律,提出了混凝土路面板脱空识别的瞬态冲击响应法.该方法可以根据板上测点功率谱图中共振峰的数量和基频大小(分析频带0~1 000 Hz),对脱空状态进行初步定量判别;结合定量激励下测点振幅拟合曲线斜率的变化,实现脱空区边界的识别.通过若干不同脱空状态路面板的模型试验和对实际混凝土路面的检测,阐述了它的检测原理和操作流程,并验证了其可行性和有效性.     

A water-fat separation imaging method for the brain on low field magnetic resonance imaging

Water-fat separation is a particularly important problem for magnetic resonance imaging. Although many methods have been proposed, the reliability is still challenging. In this work, we have presented a method based on the combination of the branch-cut method and multigrid algorithm to get a more robust performance of water-fat separation. First, the branch-cut method is applied to identify residues, which violates the requirement that the interacting phase gradient around a closed path be zero. Residues and branches are marked to be zeros and filled to the weighting factor array. Then, the unwrapped phase array can be given by the multigrid algorithm. Finally, the Dixon method for water-fat separation is applied to the unwrapped phase array. Experiments for brain scanning on the 0.3T low field MRI system demonstrate the successful application of the proposed method.