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排序方式: 共有3267条查询结果,搜索用时 15 毫秒
31.
马庭松 《安徽电子信息职业技术学院学报》2014,(3):17-19
用电负载开启时,车载蓄电池的正极输出电流会发生变化,电流值通过智能电流钳进行测量,ICP的原理是使用补偿法的感应测量(霍尔效应)。这样的优势在于测量时不影响车辆的电流。电流钳通过蓝牙将电流数据实时传输给手持诊断仪,ECOS系统软件通过预设的参数,对电流数据进行统计分析,从而获得用电负载的工作电流,用于判断用电负载是否满足设计要求。 相似文献
32.
Surface hardening of Ti-6Al-4V alloy was achieved by carburization in a molten salt bath containing BaCO3 as the carbon-yielding agent with electrolysis within the temperature range 790–930°C. The hardness of the total carburizing layer (TCD) is influenced by the bath temperature, the applied current density and the carburizing period. The major hardening effect is considered to be the formation of a solid solution of carbon in -Ti. The oxide film wrapping at the outermost surface of cathodically charged specimens, identified to be mainly BaTiO3, was formed irrespective of the bath temperature during the quenching process and has no effect on the surface hardening. The optimal carburizing parameters obtained in this study for surface hardening are carburizing at 930±10°C (bath temperature) and 0.3 A/Cm2 (applied current density) for 90 min (carburizing period), while those for tribological properties improvement are carburizing at 860±5°C and 0.3 A/Cm2 for 90 min. 相似文献
33.
研究了脉冲电流对Al-4.5Cu合金定向凝固过程及组织的影响。结果表明,随着脉冲电流峰值和频率的增大,Al—4.5Cu合金柱状晶被熔断,形态由细条状变为不连续,失去其定向凝固的取向性;且柱状晶间距随电流峰值和频率的增大而减小。由脉冲电流的引入而产生的脉冲磁压力及焦耳热效应在固液界面处造成的强烈扰动是定向凝固组织失去取向性的主要原因。 相似文献
34.
王雷 《计算机光盘软件与应用》2011,(16)
创新是国家兴旺发达的不竭动力,是一个民族进步的灵魂。一个民族没有过硬的创新能力,是不可能长久地立于民族之林的。计算机课程作为高校的基础课程,内容更新速度快,实践性和操作性都很强。计算机教师不仅要引导学生掌握计算机基础知识,还要培养学生的创新能力。本文就如何在高校计算机教学中培养学生的创新能力展开探讨,具有一定的现实意义和指导意义。 相似文献
35.
Zeyad A. Almutairi Tomasz Glawdel Carolyn L. Ren David A. Johnson 《Microfluidics and nanofluidics》2009,6(2):241-251
This study presents a new Y-channel design for measuring the zeta potential and surface conductance of a solid-liquid pairing
using the current monitoring technique. The new design improves the throughput and reliability of the testing apparatus since
the displacement between two solutions can be repeated many times without interfering with the experiments. It also increases
the accuracy of the measurement by producing sharper start and end transitions for the current–time plot of the solution displacement
process. In this design, efforts have been made to minimize the effects of electrolysis, Joule heating and undesired pressure
driven flow on the measurements. An improvement on the current–time slope analysis is also presented. The Y-channel design
was validated by comparing zeta potential measurements to published results. The zeta potential of several biological buffers
relevant to the microfluidic community in plasma treated PDMS/PDMS and PDMS/Glass microchannels are presented. Preliminary
studies of surface conductivity measurements using the Y-channel design were also conducted and are briefly discussed. 相似文献
36.
多分支平行双线输电线故障定位算法的研究 总被引:3,自引:1,他引:2
本文针对多分支平行双线输电线提出了一种新的故障定位方法。应用相同的算法对全部分支进行逐条搜索,故障分支和故障点位置可以一并被确定。经仿真证明,该方法是有效的。 相似文献
37.
38.
In the last few decades the continuous monitoring of complex dynamic systems has become an increasingly important issue across diverse engineering areas. This paper presents a pattern recognition based system that uses visual-based efficient invariants features for continuous monitoring of induction motors. The procedures presented here are based on the image identification of the 3-D current state space patterns that allow the identification of distinct fault types and, furthermore, their corresponding severity. This automatic fault detection system deals with time-variant electric currents and is based on the identification of three-phase stator currents specified patterns. Several simulation and experimental results are also presented in order to verify the effectiveness of the proposed methodology. 相似文献
39.
Dong-Suk Hong Hong-Koo Kang Dong-Oh Kim Jae-Kwan Yun Ki-Joon Han 《The Journal of supercomputing》2007,42(3):321-337
There is rapidly increasing interest in Location Based Service (LBS) which utilizes location data of moving objects. To efficiently
manage the huge amounts of location data in LBS, the GALIS (Gracefully Aging Location Information System) architecture, a
cluster-based distributed computing architecture, is proposed. The GALIS using the non-uniform 2-level grid algorithm performs
load balancing and indexing for nodes. However, the non-uniform 2-level grid algorithm has a problem creating unnecessary
nodes when moving objects are crowded in a certain region. Therefore, a new node split algorithm, which is more efficient
for various distribution of moving objects, is proposed in this paper. Because the algorithm proposed in this paper considers
spatial distribution for the current location of moving objects, it can perform efficient load balancing without creating
unnecessary nodes even when moving objects are congested in a certain region. Besides, the various data distribution configuration
for moving objects has been experimented by implementing node split simulators and it’s been verified that the proposed algorithm
can split nodes more efficiently than the existing algorithm.
相似文献
Ki-Joon Han (Corresponding author)Email: |
40.
Current variability in a wide and open lacustrine embayment in Lake Geneva (Switzerland) 总被引:1,自引:0,他引:1
A.M. Razmi D.A. Barry R. Bakhtyar N. Le Dantec A. Dastgheib U. Lemmin A. Wüest 《Journal of Great Lakes research》2013
Field measurements and numerical simulations were used to determine the effects of dominant meteorological conditions on the hydrodynamics of a wide (aspect ratio ~ 2), relatively deep (seasonally stratified) and open lake embayment (Vidy Bay, Lake Geneva). A three-dimensional hydrodynamic model (Delft3D-FLOW) was employed to simulate flow in the lake. High-resolution maps of wind, temperature and humidity (over the lake) were applied as input to drive the model. Because wind was the main force driving flow in the lake, currents in the embayment were investigated systematically for different wind conditions and seasonal stratification. Satisfactory model validation was achieved using drifter and moored measurements within the embayment. Markedly different circulation patterns were measured within the embayment, with the transition from one pattern to another occurring abruptly for small changes in wind direction. These distinct patterns resulted from relatively small changes in the large gyre of Lake Geneva's main basin, especially the angle between the current in front of the embayment and the embayment shoreline. The boundary between the embayment and the pelagic zone was defined by the largest gyre within the embayment. This study shows that, (i) in a large lake, complex current patterns can occur even within a minor embayment, and (ii) that these patterns can transition rapidly over a small range of wind directions. Near-shore gyre can occur for lengthy periods, which has implications for flushing of discharges within the embayment. 相似文献