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961.
本文介绍的机载激光测距器采用一体化设计和风冷、高重复率激光器。突出介绍了本机的机载特点和采用8031单片机对整机性能的提高。 相似文献
962.
963.
Pricing early exercise contracts in incomplete markets 总被引:1,自引:0,他引:1
We present a utility-based methodology for the valuation of early exercise contracts in incomplete markets. Incompleteness stems from nontraded assets on which the contracts are written. This methodology takes into account the individuals attitude towards risk and yields nonlinear pricing rules. The early exercise indifference prices solve a quasilinear variational inequality with an obstacle term. They are also shown to satisfy an optimal stopping problem with criterion given by their European indifference price counterpart. A class of numerical schemes are developed for the variational inequalities and a general approach for solving numerically nonlinear equations arising in incomplete markets is discussed.Accepted: May 2003, AMS Classification:
93E20, 60G40, 60J75The second author acknowledges partial support from NSF Grants DMS 0102909 and DMS 0091946. 相似文献
964.
The well-preserved bivalved microfossils collected from the Lower Cambrian limestone at theXiaoyang section in Zhenba, Shaanxi, have proved the oldest known radiolarians by meansof the electron probing analysis and morphological study under the electron scanning miroscopeand the observation of the thin section. The present discovery has shaken the theory thatThaeodaria originated from Spumellaria. Unlike the Mesozoic and Cenozoic radiolarians that areplanktonic, the Cambrian ones lived as benthos. On the basis of the chemical composition andmorphological features of these radiolarians a new genus Eoconcharium and a new family Eocon-chariidae are erected. 相似文献
965.
近程反巡航导弹雷达技术初探 总被引:1,自引:0,他引:1
针对巡航导弹的战术使用特点,结合我国中,近程防空情报雷达和火控雷达的现状与研究方向,对近以巡航导弹雷达技术研究,提出一些初步看法。 相似文献
966.
967.
Dispersal points and points on the barrier are located for a class of pursuit-evasion and interception problems. These points are determined by constructing cross sections of the isochrones, and hence by obtaining the barrier, dispersal, and control-level surfaces. The method is illustrated through examples from minimum-time interception of a target moving in a straight line in a horizontal plane.The authors are indebted to F. Neuman, M. Sidar, J. Shinar, H. Erzberger, and G. Leitmann for their comments. The first author wishes to acknowledge the financial support of the National Research Council. 相似文献
968.
A comprehensive review of the chemistry of polyhedral cluster complexes in whichs,p,d, andf-block metals are incorporated into C2B4-carborane cages to form the respective metallacarboranes is presented. The main focus of the review is directed toward systematizing the chemistry of metallacarboranes in order to promote their use as possible electronic, ceramic, and/or catalytic materials in addition to providing information on which we can test and expand our knowledge about the fundamental interactions that are at work in determining the structures and properties of these cluster complexes. 相似文献
969.
Anders Larsson 《Comptes Rendus Physique》2002,3(10):848
Roughly speaking, every commercial airliner is struck by lightning once per year. Thus, the lightning strike to aircraft is not uncommon and it poses an appreciable threat to flight safety. The understanding of the lightning strike to aircraft has been greatly enhanced during the last years thanks to a comprehensive analysis of data collected from instrumented aircraft that have been flown into thunderstorm regions. In this article, we will start with the phenomenology of the lightning strike to aircraft and continue with going deeper into the underlying physics of selected processes during the strike. To cite this article: A. Larsson, C. R. Physique 3 (2002) 1423–1444. 相似文献
970.