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排序方式: 共有179条查询结果,搜索用时 15 毫秒
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一类离散陀螺系统特征值反问题 总被引:1,自引:1,他引:0
考虑由两个实值非奇异矩阵,一个对称,一个反对称,所定义的2n个一阶常微分方程刻画的陀螺系统特征值反问题。在给定完整谱数据及部分谱数据两种情况下,给出了可解性条件及解的表示。 相似文献
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Katharina ParryMartin L. Hazelton 《Transportation Research Part B: Methodological》2012,46(1):175-188
Estimation of origin-destination (OD) matrices from link count data is a challenging problem because of the highly indeterminate relationship between the observations and the latent route flows. Conversely, estimation is straightforward if we observe the path taken by each vehicle. We consider an intermediate problem of increasing practical importance, in which link count data is supplemented by routing information for a fraction of vehicles on the network. We develop a statistical model for these combined data sources and derive some tractable normal approximations thereof. We examine likelihood-based inference for these normal models under the assumption that the probability of vehicle tracking is known. We show that the likelihood theory can be non-standard because of boundary effects, and provide conditions under which such irregular behaviour will be observed in practice. For regular cases we outline connections with existing generalised least squares methods. We then consider estimation of OD matrices under estimated and/or misspecified models for the probability of vehicle tracking. Theoretical developments are complemented by simulation experiments and an illustrative example using a section of road network from the English city of Leicester. 相似文献
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研究了单相并联谐振中频电源的晶闸管恒反压时间控制方式,阐述了其工作原理.实验结果证明该控制方式能够在各种扰动情况下,也能确保逆变晶闸管可靠关断。 相似文献
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剩余下滑力曲线在滑坡治理设计中的应用 总被引:1,自引:0,他引:1
滑坡推力在滑坡治理设计中是一个重要的计算指标.借助滑坡剩余下滑力曲线,可以对滑坡力学参数进行反演分析.通过分析剩余下滑力曲线的不同形态,提出各种形态下的滑坡治理方案,可以用于指导滑坡治理方案的设计.工程实例证明,利用剩余下滑力曲线进行滑坡治理方案设计,方便直观. 相似文献
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n个元素组成的置换a[1],a[2],…,a[n].若i<j且a[i]>a[j],则称(a[i],a[j])是一个逆序对.置换中逆序对的个数称为置换的逆序数.按定义,计算逆序数要通过n(n-1)/2此次比较,时间复杂度是O(n2).设计了一种新的方法,利用树状数组计算逆序数,时间复杂度降为O(nlog2(n)).主要思... 相似文献
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W. Fauriat C. Mattrand N. Gayton A. Beakou T. Cembrzynski 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2016,54(5):585-605
When assessing the statistical variability of fatigue loads acting throughout the life of a vehicle, the question of the variability of road roughness naturally arises, as both quantities are strongly related. For car manufacturers, gathering information on the environment in which vehicles evolve is a long and costly but necessary process to adapt their products to durability requirements. In the present paper, a data processing algorithm is proposed in order to estimate the road profiles covered by a given vehicle, from the dynamic responses measured on this vehicle. The algorithm based on Kalman filtering theory aims at solving a so-called inverse problem, in a stochastic framework. It is validated using experimental data obtained from simulations and real measurements. The proposed method is subsequently applied to extract valuable statistical information on road roughness from an existing load characterisation campaign carried out by Renault within one of its markets. 相似文献