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41.
42.
吴臻 《数学物理学报(B辑英文版)》2004,24(1):91-99
The existence and uniqueness results of fully coupled forward-backward stochastic differential equations with stopping time (unbounded) is obtained. One kind of comparison theorem for this kind of equations is also proved. 相似文献
43.
In this paper, the authors study the inclusion relations between Dirichlet type spaces DT and α-Bloch spacesβα by means of higher radial derivative. The strictness and the best possibility of the inclusion relations are shown with constructive methods.Furthermore, they sharpen one of the results when T = n, which proves that a conjecture in [7] is true. 相似文献
44.
George Stoica 《Journal of Mathematical Analysis and Applications》2007,336(2):1489-1492
We obtain a Baum-Katz-Nagaev type theorem for bounded martingale difference sequences that have more than a second moment, and prove that the celebrated Hsu-Robbins-Erd?s theorem fails for martingales. 相似文献
45.
We show that in each dimension n = 4k, k≥ 2, there exist infinite sequences of closed simply connected Riemannian n-manifolds with nonnegative sectional curvature and mutually distinct oriented cobordism type.
W. Tuschmann’s research was supported in part by a DFG Heisenberg Fellowship. 相似文献
46.
A Liouville type theorem for polyharmonic elliptic systems 总被引:1,自引:0,他引:1
Yajing Zhang 《Journal of Mathematical Analysis and Applications》2007,326(1):677-690
In this paper, we consider the polyharmonic system m(−Δ)U=Vq,m(−Δ)V=Up in RN, for m>1, N>2m, with p?1, q?1, but not both equal to 1, where m(−Δ) is the polyharmonic operator. Set α=2m(q+1)/(pq−1), β=2m(p+1)/(pq−1), for α,β∈[(N−2)/2,N−2m), we prove the nonexistence of positive solutions. 相似文献
47.
Tsuyoshi Katayama 《Queueing Systems》1992,11(3):299-306
This paper derives a conservation law for mean waiting times in a single-server multi-class service queueing system (M
X/G/1 type queue) with setup times which may be dependent on multiple customer classes and its arrival batch size by using the work decomposition property in the queueing system with vacations. 相似文献
48.
HypersurfacewithConstantMainCurvatureSymmetricFunctions¥WuBaoqiang;SongHongzao(XuzhouTeachersCollege,221009)(HenanUniversity,... 相似文献
49.
S K Deshpande S M Chaudhari Ashok Pimpale A S Nigavekar S B Ogale V G Bhide 《Pramana》1991,37(4):373-385
An automated linear laboratory EXAFS spectrometer of the Johansson type has been indigenously developed. Only two translational
motions are required to achieve the necessary Rowland circle configuration for the (fixed) X-ray source, the dispersing and
focusing bent crystal and the receiving slit. With the available crystals the spectral region from 5 to 25 keV can be scanned.
The linear motions of the crystal and receiving slit including the detector assembly are achieved by employing software-controlled
DC motors and utilizing optical encoders for position sensing. The appropriate rotation of the crystal is achieved by the
geometry of the instrument. There is a facility to place the sample alternately in the path of the X-ray beam and out of the
path to record both the incident X-ray intensityI
0 and the transmitted intensityI employing the scintillation detector. An arrangement with a two-window proportional detector before the sample to measureI
0 and the scintillation detector to recordI is also developed; in this case it is not necessary to oscillate the sample. Fast electronic circuits are employed to minimize
counting errors. The instrument is user-friendly and it is operated through a menu-driven IBM compatible PC. EXAFS spectra
of high resolution have been recorded using the spectrometer and employing the Si(111) reflecting planes; the X-ray source
being a Rigaku 12 kW rotating anode with Cu target. We describe the spectrometer and discuss its performance with a few representative
spectra. 相似文献
50.
S.V. Astashkin F.A. Sukochev 《Journal of Mathematical Analysis and Applications》2007,336(2):1231-1258
We catalogue all Marcinkiewicz function and sequence spaces with the Banach-Saks property and present necessary and sufficient conditions for a wide subclass of spaces to possess the p-Banach-Saks property, 1<p<∞. We apply our results to several open problems. 相似文献