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921.
对以强猝灭气体工作的小间隙多丝室及其放电机制进行了研究,实验表明,因为工作在饱和模式区,这种室同时具有很高的气体放大和相当快的时间特性.文中探讨了放电机制,雪崩中空间电荷效应以及电离光子的产生和作用是重要的因素,而其中后一因素又受到强猝灭气体的抑制.  相似文献   
922.
电子电路的计算机辅助设计方法是促进电子技术发展的一种有效工具。本文介绍如何将行之有效的正交优化法与国际盛行的模拟电子电路的分析程序SPICE相结合,形成了ACOD软件,将CAA扩展为CAD。  相似文献   
923.
This paper deals with the theory and estimation of the short-run supply of roundwood under nonlinear (progressive) income taxation. The theoretical part of the paper uses the two-period consumption harvesting model to introduce nonlinear income taxes into the forest management problem and presents a simple method to determine the optimal supply of roundwood in this case. In the empirical part of the paper, the model is specified in a way suitable for econometric analysis. The estimation method is the maximum likelihood method, and the estimation results seem to support the theoretical model. Finally, some results from model simulation imply that income taxation may have a nonnegligible impact on the supply of roundwood.  相似文献   
924.
Summary A review of the correlations between gravitational-wave detectors and particle detectors during SN1987A is given. The correlation between the Maryland and Rome g.w. detectors with the Mont Blanc neutrino detector is illustrated. This correlation extends during a period of one or two hours centred at 2∶45 UT of 23 February 1987, with the ?neutrino? signals delayed by (1.1±0.5) s and with a probability of the order of 10−5 to be accidental. Using the data obtained with the Kamiokande and IMB detectors, with the same statistical choices and procedures for the data analysis used previously, the above result is confirmed with a probability of the order of 10−3 or 10−4 that the additional correlation be accidental. Paper presented at the V Cosmic Physics National Conference, S. Miniato, November 27–30, 1990.  相似文献   
925.
This paper gives sufficient conditions for the existence of periodic solutions of twist type of a time-dependent differential equation of the second order. The concept of periodic solution of twist type is defined in terms of the corresponding Birkhoff normal form and, in particular, implies that the solution is Lyapunov stable. Some applications to nonlocal problems are given.  相似文献   
926.
本文提出一种利用材料Hugoniot数据研究高压下离子晶体中微观离子状态及其离子间排斥作用势的新方法。对氢化锂晶体进行研究时,我们得到Li~+和H~-离子之间排斥作用势函数,结果表明文献〔1〕中提出的离子压缩效应具有客观性。  相似文献   
927.
LetK be a quadratic Geld, and letR(N) be the number of integer ideals inK with norm at most AT. Letx with conductork be the quadratic character associated withK. Then |R(N)−NL(1,x)|⩽Bk 50/73 N 23/73(logN)461/146 forNAk, whereA andB are constants. ForNAk c,C sufficiently large, the factork 50/73 may be replaced by (d(k))4/73 k 46/73. Dedicated to the memory of Professor K G Ramanathan  相似文献   
928.
The management of voice disorders may follow one of four approaches: surgical, pharmacological, technical aid, and/or voice therapy. The latter approach offers a wide variety of techniques, each based on certain theoretical beliefs. One of these techniques is the Smith Accent Method. The principles and goals of the Accent Method are presented. The results of its application are discussed. This technique proved effective for cases of functional voice disorders, vocal nodules, and some degrees of vocal fold paralysis.  相似文献   
929.
We shall prove here that any binary relation on a base E with cardinality n > 6 is reconstructible from its restrictions of cardinality 2, 3, 4 and (n - 1). This proof needs results of part I of this paper where we characterize any pair of relations R, R' which are 2-, 3- and 4-hypomorphic. As a corollary we obtain that any binary relation is (n - 4)-reconstructible (when n > 9).  相似文献   
930.
Summary We report on the development of an adaptive optimum filter for processing the data of a resonant bar gravitational-wave detector. This filter, based on the matched-filter theory, is adaptive in the sense that the function it realizes is derived from the actual noise spectrum of the data being analysed (instead from an idealized model of the noise). Its implementation is mostly based on frequency domain techniques. We also report on the application of the new filter to the data of the cryogenic antenna Explorer of the Rome group, with particular reference to the comparison between its performance and that of an otpimum filter with fixed values of the parameters.  相似文献   
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