The clinical analysis of three methods in the treatment of intracranial bacterial infection

Objective To analyze the effect of three therapeutic methods to find an optimal approach to the treatment of intracranial bacterial infection by retrospectively reviewing 33 intracranial bacterial infection patients who were admitted from 1995 to 2008 in oar hospital. Methods The treatments by intermittent lumbar puncture,continuous lumbar subarachnoid space drainage, and embedment of Ommaya cyst for continuous drainage from the ventricles were performed in 15 cases, 12 cases, and 6 cases respectively along with intravenous application of full dose of antibiotics. Results Nineteen cases were cured and the best prognosis was from the group of Ommaya cyst embedment and continuous drainage from the ventricles. Conclusion Management goals are prompt recognition of the central nervous system (CNS) infection, rapid identification of causative organisms and initiation of treatment with the optimal management methods for complications. Embedment of Ommaya cyst for continuous drainage from the ventricle is a safe and effective treatment for intracranial bacterial infection.     

On the application of hydraulic theory to the deep-water flow through the Irbe Strait

A flow-dependent critical-point method for investigating topographically controlled flow in natural channels is applied to the bottom current through the Irbe Strait connecting the Baltic proper and the Gulf of Riga. This approach is based on the functional formalism due to Gill [Gill, A.E., 1977. The hydraulics of rotating-channel flow. J. Fluid Mech., 80, 641–671.], and here is used for the stratified flow structure observed during the IRBEX-95 field campaign. A critical section of the realizable flow regime was found to be located slightly downstream of the most pronounced horizontal constriction of the channel. The predicted baroclinic volume flux 7200 m³ s⁻¹ overestimates the observed mean bottom-water transport by around 30%, a discrepancy which most likely can be explained by the lack of sea level conditions and friction in the model.     

基于OpenFOAM的发动机舱回流计算方法研究

研究车辆在怠速工况下的发动机舱热空气回流问题，基于OpenFOAM 软件进行回流计算方法的开发。通过设置监控面及组分转换面来重新定义格栅新空气和舱内回流热空气等组分，可直接计算出回流在监控面上的分布及回流率和回流量。根据开发的方法对某款插电式混合动力汽车（Plug-in Hybrid Electric Vehicle，PHEV）车型进行计算并提出不同的优化方案，使其发动机舱回流率从32.7% 分别降低至24.0%和9.3%，回流量从0.169 kg/s分别降低至0.128 kg/s和0.048 kg/s，从而降低了冷凝器等散热器的进风温度，提高了怠速工况下热管理系统的性能。     

Flow-field guided steering control for rigid autonomous ground vehicles in low-speed manoeuvring

ABSTRACT

This paper studies the low-speed manoeuvring problem for autono-mous ground vehicles operating in complex static environments. Making use of the intrinsic property of a fluid to naturally find its way to an outflow destination, a novel guidance method is proposed. In this approach, a reference flow field is calculated numerically through Computational Fluid Dynamics, based on which both the reference path topology and the steering reference to achieve the path are derived in a single process. Steering control considers three constraints: obstacle and boundary avoidance, rigidity of the vehicle, plus the non-holonomic velocity constraints due to the steering system. The influences of the parameters used during the flow field simulation and the control algorithm are discussed through numerical cases. A divergency field is defined to evaluate the quality of the flow field in guiding the vehicle. This is used to identify any problematic branching features of the flow, and control is adapted in the neighbourhood of such branching features to resolve possible ambiguities in the control reference. Results demonstrate the effectiveness of the method in finding smooth and feasible motion paths, even in complex environments.     

Assessment of the volume of fluid method for free-surface wave flow

This study was concerned with the free-surface wave flow around a surface-piercing foil. The volume of fluid method implemented in a Navier–Stokes computational fluid dynamics code was employed. Three widely used discretization schemes for the volume of fluid method were assessed for a test case that involved general ship waves, spilling breaking waves in front of the leading edge, and bubbly free surfaces in separated regions. A single computational approach was selected for the comparison, and a grid-dependence study was carried out. The computational results were validated against existing experimental data, showing good agreement. The validation results suggest that all three discretization schemes perform well, but the best and most efficient results were obtained using the high-resolution interface capturing scheme.     

RIGOROUS PROOF FOR CHARACTERISTICS OF PRACTICABLE MAGNETIC POTENTIOMETERS AND THEIR APPLICATION

IntroductionThe magnetic potentiometer or Rogowski coilhas been widely applied for measuring the heavyAC- current and pulsed current[1～ 3 ] . It has variousadvantages among which the following are of vitalimportance:1 The relation between the inducedoutput voltage in secondary winding and the differ-ential of the primary currents is exactly linear;2The output voltage is independent of the positionof the primary circuit;3 The outputvoltage is un-affected by stray fields of the current which …     

磁电式速度传感器设计与应用

分析磁电式速度传感器早期产品故障现象,对传感器进行了改进设计,得出设计要点,阐述了传感器应用须注意的问题。改进设计已成功应用于为GE公司开发的3款磁电式速度传感器上。     

轮胎压路机驱动方式的对比分析

通过对现有市场上的轮胎压路机机械传动、液力传动、液压传动3种传动方式的对比分析，归纳出其优缺点，综合分析得出液压传动的轮胎压路机在性能、工作效率、维护保养、驾驶的舒适性方面有着较为明显的优势。     

船用柴油机磁场仿真计算及验证

介绍了采用电磁场数值计算方法,利用有限元分析软件ANSYS对柴油机磁场进行仿真计算的过程,并将计算结果与实验测量的数据进行了比较,说明该方法完全可以用于工程实践.     

上海地铁13号线车辆底架线槽与布线设计探究

由于地铁车辆的大部分重要电缆都位于车体下方,电缆的外部环境相当恶劣,为了有效防护电缆以减少安全隐患,在地铁车辆上使用了线槽。在模块化概念深入企业设计与生产理念的现状下,结合上海地铁13号线车辆项目,对线槽设计、布线要求、电磁兼容、有限元分析等进行了分析。