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A new approach to estimate vehicle tire forces and road maximum adherence is presented. Contrarily to most of the previous works on this subject, it is not an asymptotic observer-based estimation, but a combination of elementary diagnosis tools and new algebraic techniques for filtering and estimating derivatives of noisy signals. In a first step, instantaneous friction and lateral forces will be computed within this framework. Then, extended braking stiffness concept is exploited to detect which braking efforts allow to distinguish a road type from another. A weighted Dugoff model is used during these ‘distinguishable’ intervals to estimate the maximum friction coefficient. Very promising results have been obtained in noisy simulations and real experimentations for most of the driving situations.  相似文献   
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4 Finishing The purpose of finishing leather is to improve its serviceability by protecting it from damage by water, soil and mechanical action. Finishing modifies the shade, gloss and handle of the leather, improves its physical properties such as its lightfasthess and rubfastness, and hides any defects and  相似文献   
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The perception westerners have of ruins underwent drastic transformations in the second half of the twentieth century. The realities of World War Two and the growing number of environmental problems made everyone realise that a ruin can be more than some enchanting reminder of distant cultures. Ruins stopped being objects of desire, precious anachronisms for adventurers to appropriate. This paper surveys emerging sensibilities towards ruins in literature, arts, archaeology and architecture. It presents a new vision, quite opposite to, but as powerful as the Beaux-Arts perspective.  相似文献   
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The initiating ability of tetramethylene zwitterions formed from cyclobutane adducts of donor olefins with TCNE was investigated. Polar solvents increased the ability of vinyl ether-TCNE cyclobutane adducts to initiate the cationic polymerization of N-vinylcarbazole. The concept of charge separation in the tetramethylene zwitterions was also investigated.  相似文献   
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The microstructure and magnetic properties of binary hypo- and hyper-eutectoid Fe–C alloys were studied. The investigations have been carried out on the samples in the as-cast state, after a long annealing at 725 °C and on the specimens after the high-pressure torsion (HPT). The deformation was carried out at the ambient temperature and the pressure of 5 GPa. The grain size after HPT is in the nanometer range. Long annealing leads to a drastic decrease of the coercivity in comparison with the as-cast alloys. In all alloys the coercivity H c increases with increasing carbon content. The distance L between pinning points for domain walls decreases with increasing carbon content. Increase of the coercivity and decrease of L are more pronounced below the eutectoid concentration. The coercivity of the nanostructured samples is higher than that of the as-cast alloys. Due to the pinning of domain walls by the cementite particles, the hysteresis loop in the coarse-grained alloys both in as-cast and annealed states has a narrowing near the zero magnetization.  相似文献   
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For networks that are directed or can be represented by a directed network,reversing one or more of the uni-directional links may provide the ability to reconnect a network that has been disconnected by link failure.In this paper,a new approach to reconfigure such networks is proposed.We develop a linear time algorithm which,when reachability has been destroyed by the removal of a single link,optimally restores reachability through the reversal of selected links.Multi-link failure reconnectability is discussed and an algorithm with polynomial complexity is given which provides a nearly optimum solution to reconnect the network.We show that the reliability of a network that allows reversals is at least twice more than that in which reversals are not permitted.Unfortunately,the reconnection of some networks cannot be established.Therefore,we discuss the maximization of reachability of such networks so that each node can reach maximum number of the other nodes.  相似文献   
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The reachability of a strongly connected network may be destroyed after link damage,Since many networds have directed links with the potential for reversal,the reachability may be restored by reversing the direction of links.In this paper,the reliability of a network that allows reversal of links in discussed.  相似文献   
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