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991.
992.
The effective signal in x-ray diffraction analysis of material properties often contains high frequency (noise) and low frequency
(trend) components as additive parts. It is necessary to extract the effective signal from the noise to ensure high quality
of signal processing. Digital filters of Volterra type are proposed for filtering purposes and a comparison of Volterra filtration
implemented on x-ray diffraction data versus results from a set of other digital filters is given. 相似文献
993.
The educational system has gradually shifted from a face-to-face to an e-learning system, which has become prevalent in advanced countries with the advance of information technology, and connection of global networks. Accordingly, a growing demand is emerging for more reliable individual certification with technical precision in order to measure and record learning achievements and credentials of participants. The present system has a limit in terms of registration capacity, therefore, its accuracy has often been questioned. Against this background, an individual certification system is proposed particularly for access control in e-learning. Under our proposed system, a compact optical correlator for facial recognition is employed. This correlator was previously tested for of biometrics authentication accuracy and proved highly reliable, having recorded remarkably low error rates (below 1%). The recorded error rate is sufficiently robust that the system itself can be regarded as a valid and practical viable attestation system. 相似文献
994.
He Renyi 《Southeast Asian Bulletin of Mathematics》2003,26(2):215-221
In this paper, we get some properties in the dual space of Lk-UR and k-SS Banach space.AMS Subject Classification: 46B09 相似文献
995.
针对带约束的凸多面体线性不确定模型,提出了一种新型鲁棒预测控制方法,它采用离散化的不确定模型构造最小-最大优化控制问题,并在其中直接引入状态反馈机制,与其他最小-最大预测控制方法相比,这种方法等效于增加了控制序列的长度,为优化问题增加了更多的自由度,从而扩大了可行域,作为最小化目标的是离散化不确定系统在整个预测时域上二次型成本函数的最大值,而不是各预测阶段应成本项的上界之和,从而减少了与最小-最大优化相关的方程个数,有利于降低计算复杂性,文中进一步证明了不确定系统的闭环稳定性取决于优化问题在初始时刻的可行性,并将优化问题转化为线性矩阵不等式形式。最后,以数值仿赵例子验证了方法的有效性。 相似文献
996.
Franz Merkl 《Probability Theory and Related Fields》2003,126(3):307-338
This article describes the almost sure infinite volume asymptotics of the ground state energy of random Schr?dinger operators
with scaled Gibbsian potentials. The random potential is obtained by distributing soft obstacles according to an infinite
volume grand canonical tempered Gibbs measure with a superstable pair interaction. There is no restriction on the strength
of the pair interaction: it may be taken, e.g., at a critical point. The potential is scaled with the box size in a critical
way, i.e. the scale is determined by the typical size of large deviations in the Gibbsian cloud. The almost sure infinite
volume asymptotics of the ground state energy is described in terms of two equivalent deterministic variational principles
involving only thermodynamic quantities. The qualitative behaviour of the ground state energy asymptotics is analysed: Depending
on the dimension and on the H?lder exponents of the free energy density, it is identified which cases lead to a phase transition
of the asymptotic behaviour of the ground state energy.
Received: 24 June 2002 / Revised version: 17 February 2003
Published online: 12 May 2003
Mathematics Subject Classification (2000): Primary 82B44; Secondary 60K35
Key words or phrases: Gibbs measure – H?lder exponents – Random Schr?dinger operator – Ground state – Large deviations 相似文献
997.
Non-additivity effects in coupled dynamic-stochastic systems are investigated. It is shown that there is a mapping of the
replica approach to disordered systems with finite replica indexn on Tsallis non-extensive statistics, if the average thermodynamic entropy of the dynamic subsystem differs from the information
entropy for the probability distribution in the stochastic subsystem. The entropic indexq is determined by the entropy difference ΔS. In the case of incomplete information, the entropic indexq=1−n is shown to be related to the degree of lost information. 相似文献
998.
用溶胶-凝胶法制备了在可见光照射下具有光催化活性的掺杂P(t Ⅳ)离子的非晶态微孔TiO2,表面积为160~200 m2/g;含3.0%Pt(Ⅳ)的AMM-Ti具有最大的光催化活性. X射线精细结构分析(EXAFS)表明,单个的PtCl4分子均匀地分布在非晶态二氧化钛表面;用这种光催化剂降解2,4-二氯苯氧基乙酸时,2,4-二氯苯酚是主要的中间物,通过Langmuir-Hinshelwood 方程的线性形式估算了反应速率常数k 和吸附平衡常数K,研究了光催化起始反应速率和反应物起始浓度之间的关系,同时,提 相似文献
999.
We prove that there exists a maximal ideal of a BCI-algebra X in which each subalgebra is an ideal.AMS Subject Classification (1991): 06F35, 03G25.The second author was supported by the LG Yonam Foundation (1995). 相似文献
1000.