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61.
许力 《港口科技》2011,(10):34-38,42
为进一步实现节能减排,研发了集装箱装卸机械电能控制系统。介绍了该电能监控系统的整体结构、系统配置、软件系统、系统网络图等情况。阐述了系统的作用。指出:通过电能监控系统实现对分类能耗、分项电能的远程监测与管理成为港口机械管理发展的必然趋势。  相似文献   
62.
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.  相似文献   
63.
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.  相似文献   
64.
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。  相似文献   
65.
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.  相似文献   
66.
目前运营时速160 km以下(双箱运输)有砟轨道隧道内轮廓难以满足大型养护机械(特别是大型清筛机)作业空间需求,通过对新建时速160 km以下电气化铁路(双箱运输)有砟轨道隧道的建筑限界、接触网悬挂方式及布置、大型养护机械空间需求、轨道结构形式、侧沟及电缆槽设置等内轮廓影响因素进行综合分析,确定单双线铁路有砟轨道隧道内轮廓控制性尺寸、拟定内轮廓方案,通过对各型内轮廓方案的结构安全性、经济性及施工便利性比较,给出推荐方案,为通用图编制和纳入规范奠定基础。  相似文献   
67.
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.  相似文献   
68.
液压油过滤技术在工程机械中的应用   总被引:1,自引:0,他引:1  
针对工程机械液压油污染等级问题,探讨了液压油过滤技术根据液压油过滤工艺设计了一种具有三级滤芯的过滤机和管路组成的过滤系统,使用快换接头将过滤系统与工程机械液压油箱连接,能满足大批量工程机械液压油过滤作业的需要。用检测仪检测证明:该过滤系统过滤后的液压油污染等级优于行业要求标准  相似文献   
69.
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。  相似文献   
70.
文章介绍了机械设备发生故障后,电气故障的查找与分析方法,对分析故障原因的状态分析法、图形分析法、单元分析法、回路分析法等方法以及故障点查找的手段和方法进行了分析和阐述,对工程机械常见机械和电气设备故障的检查与排除提供了经验。  相似文献   
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