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31.
吴桂荣 《数学物理学报(A辑)》1998,18(1):116-120
该文对一般的随机变量序列及相当弱的系数条件研究了随机级数定义的整函数的奈望里纳特征函数,并证明了它是几乎必然无有限例外值的. 相似文献
32.
Keith Warren Julien C. Sprott Raymond C. Hawkins 《Nonlinear dynamics, psychology, and life sciences》2002,6(1):55-70
In recent years there has been considerable interest in the construction of nonlinear models of the dynamics of human behavior. In this exploratory article we argue that attempts at controlling problematic thoughts, emotions, or behaviors can lead to nonlinearity in mental/behavioral dynamics. We illustrate our model by fitting threshold autoregression models to self-recorded time series of the daily highs in intensity of anxiety and obsessive ruminations, kept by an individual in therapy for this problem. In our discussion, we raise the possibility that bifurcations that occur in this nonlinear model may offer insight into mental control paradoxes. 相似文献
33.
杨钟玄 《新疆大学学报(理工版)》2002,19(3):266-271
先对正项级数敛生判别法的粗细与强弱问题进行了辨析,然后建立了三个有关正项级数剑散判别的命题,分别比较了三组判别法之间的强弱关系。 相似文献
34.
35.
Feng Dejun 《分析论及其应用》2003,19(4)
1 IntroductionForany 0 <λ <1 ,letνλ denotethedistributionof ∞n=0 εnλn wherethecoefficientsεnareeither0or1 ,chosenindependentlywithprobability12 foreach .Itistheinfiniteconvo lutionproductofthedistributions 12 (δ0 +δλn) ,givingrisetotheterm“infiniteBernoulliconvolution”orsimply“Bernoulliconvolution” .TheBernoulliconvolutioncanbeexpressedasaself similarmeasureνλsatisfyingtheequationνλ =12 νλ φ- 10 + 12 νλ φ- 11,( 1 .1 )whereφ0 (x) =λxand φ1(x) =λx + 1 .Thisme… 相似文献
36.
The main objects of study in this article are two classes of Rankin–Selberg L-functions, namely L(s,f×g) and L(s, sym2(g)× sym2(g)), where f,g are newforms, holomorphic or of Maass type, on the upper half plane, and sym2(g) denotes the symmetric square lift of g to GL(3). We prove that in general, i.e., when these L-functions are not divisible by L-functions of quadratic characters (such divisibility happening rarely), they do not admit any LandauSiegel zeros. Such zeros, which are real and close to s=1, are highly mysterious and are not expected to occur. There are corollaries of our result, one of them being a strong lower bound for special value at s=1, which is of interest both geometrically and analytically. One also gets this way a good bound onthe norm of sym2(g). 相似文献
37.
John Frederick Jardine 《Mediterranean Journal of Mathematics》2006,3(2):251-258
It is shown that the groupoid of G-torsors, suitably defined, can be used to construct a model for the stack associated to G, for arbitrary sheaves of groupoids G.
This research was supported by the Natural Sciences and Engineering Research Council of Canada. 相似文献
38.
For about thirty years, time series models with time-dependent coefficients have sometimes been considered as an alternative
to models with constant coefficients or non-linear models. Analysis based on models with time-dependent models has long suffered
from the absence of an asymptotic theory except in very special cases. The purpose of this paper is to provide such a theory
without using a locally stationary spectral representation and time rescaling. We consider autoregressive-moving average (ARMA)
models with time-dependent coefficients and a heteroscedastic innovation process. The coefficients and the innovation variance
are deterministic functions of time which depend on a finite number of parameters. These parameters are estimated by maximising
the Gaussian likelihood function. Deriving conditions for consistency and asymptotic normality and obtaining the asymptotic
covariance matrix are done using some assumptions on the functions of time in order to attenuate non-stationarity, mild assumptions
for the distribution of the innovations, and also a kind of mixing condition. Theorems from the theory of martingales and
mixtingales are used. Some simulation results are given and both theoretical and practical examples are treated.
Received 2004; Final version 23 December 2004 相似文献
39.
我们定义了(H,λ)求和法,它含有(N,pn),(R^rn)和(Vmn)求和法。讨论了函数f(x)∈C^r[-1,1](r∈N0)以及f(x)∈W^rH^a(r∈N0,0<a<1)的切比晓夫-富里埃级数的逼近阶。 相似文献
40.
采用固相反应法合成A缺位的(La0.8Sr0.2)0.95MnO3(LSM95)作为阴极材料,Zr0.9Sc0.1SO1.95(SSZ)商业粉体作为电解质材料,溶胶-凝胶法合成的La0.8Sr0.2Cr0.5Mn0.5O3-(LSCrM)作为阳极电催化材料,利用流延、共烧结及浸渍法得到结构为LSCrM-CeO2|SSZ|3YSZ-LSM95的阴极支撑型固体氧化物燃料电池,分别在氢气气氛和甲烷气氛中进行电化学性能测试. 结果表明,浸渍0.11 g·cm -2 CeO2的LSCrM-CeO2|SSZ|3YSZ-LSM95单电池在以CH4为燃料时,600、650、700、750和800 oC下的功率密度分别为1.68、4.70、12.40、28.08和54.78 mW·cm -2,表现出一定的电化学性能和较好的稳定性. 相似文献