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101.
NBR/PP热塑性弹性体研究进展 总被引:12,自引:0,他引:12
阐述了NBR/PP共混热塑性弹性体动态硫化胶的国内外研究进展、微观相态结构、性能、应用及展望。 相似文献
102.
PENGLiming MAOXiemin XUKuangdi DINGWenjiang 《稀有金属(英文版)》2002,21(1):62-66
In order to develop a new type of contact cable with high strength and high electrical conductivity, Cu-Cr alloy series were selected as materials and Cu-Cr alloy castings were produced by means of directional solidification continuous casting (DSCC) process. The results show that the fibrillar strengthening phase, 13-Cr, orderly arranges among the copper matrix phase along the wire direction; and a microstructure of in-situ composite forms, which retains the basic property of good conductivity of the copper matrix and meanwhile obtains the strengthening effect of [3-Cr phase. The production technology as well as the mechanical property, electrical property, and synthetic property of the in-situ composite contact cables was discussed. 相似文献
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Behaviour of a series of lubricant oils and the effect of a non stoichiometric inorganic compound, as solid extreme pressure additive, on rolling fatigue life are studied using the rolling four-ball accelerated service simulation test proposed by Barwell and Scott. The results show, in all tested cases, the remarkable efficacy of this type of additive. The Total Acidity Number (tan) was found to increase with performance time for the case of the base lubricant, while for the oils with additives, it remained at its constant low value. This led to a proposal of a possible mechanism of the additive performance in the rolling process. 相似文献
106.
Hong Jeong Jeong‐Ho Park 《International Journal of Adaptive Control and Signal Processing》2002,16(1):1-23
Tracking targets of interest is one of the major research areas in radar surveillance systems. We formulate the problem as incomplete data estimation and apply EM to the MAP estimate. The resulting filter has a recursive structure analogous to the Kalman filter. The advantage is that the measurement‐update deals with multiple measurements in parallel and the parameter‐update estimates the system parameters on the fly. Experiments tracking separate targets in parallel show that tracking maintenance ratio of the proposed system is better than that of NNF and RMS position error is smaller than that of PDAF. Also, the system parameters are correctly obtained even from incorrect initial values. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
107.
战术弹道导弹落点预报的一种方法 总被引:1,自引:0,他引:1
根据椭圆弹道理论,提出了一种可以用于反战术弹道导弹作战的预测弹道及预报落点的方法,给出了算例,并分析了产生误差的原因和对预测结果的影响程度。 相似文献
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In this paper we describe, from a theoretical point of view, critical configurations for the projective reconstruction of
a set of points, for a single view, i.e. for calibration of a camera, in the case of projections from ℙk to ℙ2 for k ≥ 4. We give first a general result describing these critical loci in ℙk, which, if irreducible, are algebraic varieties of dimension k−2 and degree 3. If k=4 they can be either a smooth ruled surface or a cone and if k = 5 they can be a smooth three dimensional variety, ruled in planes, or a cone. If k≥ 6, the variety is always a cone, the
vertex of which has dimension at least k − 6. The reducible cases are studied in Appendix A.
These results are then applied to determine explicitly the critical loci for the projections from ℙk which arise from the dynamic scenes in ℙ3 considered in [13].
Marina Bertolini is currently Associate Professor of Geometry at the Department of Mathematics at the Università degli Studi di Milano, Italy.
Her main field of research is Complex Projective Algebraic Geometry, with particular interest for the classification of projective
varieties and for the geometry of Grassmann varieties. On these topics M. Bertolini has published more than twenty reviewed
papers on national and international journals. She has been for some years now interested also in applications of Algebraic
Geometry to Computer Vision problems.
Cristina Turrini is Associate Professor of Geometry at the Department of Mathematics of Università degli Studi di Milano, Italy. Her main
research interest is Complex Projective Algebraic Geometry: subvarieties of Grassmannians, special varieties, automorphisms,
classification. In the last two years she has started to work on applications of Algebraic Geometry to problems of Computer
Vision. She is author or co-author of about thirty reviewed papers. She is also involved in popularization of Mathematics,
and on this subject she is co-editor of some books. 相似文献