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一、概述 YD系列轻型交流高压试验变压器是根据机电部《试验变压器》标准在原同类产品基础上经过大量改进后而生产的,YD(JZ)系列轻型交直流高压试验变压器是在YD系列试验变压器的基础上按照国家标准《ZB...
杯突试验按照国家标准,“试验采用端部为球形的冲头,将夹紧的试样压入压模内,直至出现穿透裂缝为止,所测量的杯突深度即为试验结果。”这种试验通常是在杯突试验机上进行。试样在做过杯突试验后就像只冲压成的杯子...
(Erichsen试验)如图1所示。试验时,90mm×90mm的试样或宽度90mm的条料试样放在凹模与压边圈之间压死(压边力取10kN),测出试件刚好破裂时的凸模压入深度IE。杯突试验是模拟胀形工艺,...
参数估计法实现的互相关流量测量系统
由于传统相关流量计测量精度易受外界条件影响,故系统采用参数估计实现渡越时间的计算。其主要思想是把测量值不断地逼近理论值,从而不断地修改数学模型中的参数;当参数确定后,计算流量值。系统采用多核处理器OMAP3530,提高系统的实时性。试验数据表明,采用参数估算法实现的互相关流量计具有精度高、实时性好等优点,并具有实际的工程应用价值。
用模态参数估计剪切型建筑的损伤
提出了一种利用不完整模态多数估计结构损伤的方法。不完整模态体现在模态数少于自由度数,测点数少于自由度数。通过不完整模态参数建立了完整的剪切型模型,然后利用结构变化后产生的广义残余力来估计结构的损伤。该方法的优点:(1)不仅可以估计刚度损伤还可以估计质量的变*化;(2)利用的是不完整模态。最后用该方法对一个结构模型的振动台试验的结果做了分析。
《国外数学名著系列(续一)(影印版)40:模型参数估计的反问题理论与方法》主要内容:Prompted by recent developments in inverse theory, Inverse Problem Theory and Methods for Model Parameter Estimation is a completely rewritten version of a 1987 book by the same author. In this version there are many algorithmic details for Monte Carlo methods, least- squares discrete problems, and least-squares problems involving functions. In addition, some notions are clarified, the role of optimization techniques is underplayed, and Monte Carlo methods are taken much more seriously. The first part of the book deals exclusively with discrete inverse problems with afinite number of parameters, while the second part of the book deals with general inverse problems.
The book is directed to all scientists, including applied mathematicians, facing the problem of quantitative interpretation of experimental data in fields such as physics, chemistry, biology, image processing, and information sciences. Considerable effort has been made so that this book can serve either as a reference manual for researchers or as a textbook in a course for undergraduate or graduate students.
Prompted by recent developments in inverse theory, Inverse Problem Theory and Methods for Model Parameter Estimation is a completely rewritten version of a 1987 book by the same author. In this version there are many algorithmic details for Monte Carlo methods, leastsquares discrete problems, and least-squares problems involving functions. In addition, some notions are clarified, the role of optimization techniques is underplayed, and Monte Carlo methods are taken much more seriously. The first part of the book deals exclusively with discrete inverse problems with afinite number of parameters, while the second part of the book deals with general inverse problems.
《试验统计方法》主要内容:田间试验的设计与实施;次数分布和平均数、变异数;理论分布和抽样分布;统计假设测验;方差分析;卡平方测验;参数估计方法等等。2100433B
牵引试验的目的是测定拖拉机各项牵引指标和经济指标,画出牵引特性曲线。对于新试制的拖拉机、新引进的样机以及原有产品的质量检查,都要进行牵引试验,画出牵引特性曲线,用于指导设计、生产和使用。
牵引试验的测试方法有定距离法和定时间法两种。采用定距离法作牵引试验是指拖拉机在调整好的工况下,使其稳定行驶完规定的距离,测量并记录各项参数的实测数据;然后,调整到另一工况,重复上述测量,如此逐点进行,直至完成全部试验。定时间法则是使拖拉机在规定的路面上,不停车,连续改变工况进行试验,每改变一次工况,稳定后,随即在规定时间内:测取并记录各参数的平均值。通常走完全程,便完成一个挡位的测量。