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1.
The traditional probability density evolution equations of stochastic systems are usually in high dimensions. It is very hard
to obtain the solutions. Recently the development of a family of generalized density evolution equation (GDEE) provides a
new possibility of tackling nonlinear stochastic systems. In the present paper, a numerical method different from the finite
difference method is developed for the solution of the GDEE. In the proposed method, the formal solution is firstly obtained
through the method of characteristics. Then the solution is approximated by introducing the asymptotic sequences of the Dirac
δ function combined with the smart selection of representative point sets in the random parameters space. The implementation
procedure of the proposed method is elaborated. Some details of the computation including the selection of the parameters
are discussed. The rationality and effectiveness of the proposed method is verified by some examples. Some features of the
numerical results are observed. 相似文献
2.
为降低基于部分传输序列法(PTS)的峰均功率比(PAPR)抑制技术的复杂度,文中研究了OFDM时域信号最大峰值点的位置与采用部分传输序列法后最大峰值点位置之间的关联性,提出了一种寻找最优相位因子序列的简化算法,该算法用抽样序列代替原始序列进行搜索。由于新算法采用的样点数目少于原始样点数目,因此可以大幅降低PTS处理过程的计算复杂度。仿真结果表明,新算法采用的数据量只有原始数据的50%,而性能仅仅损失0.2~1 dB。 相似文献
3.
Tor Helleseth Daniel Sandberg 《Applicable Algebra in Engineering, Communication and Computing》1997,8(5):363-370
Differentially uniform power mappings of the form f (x)=x
d
over GF(p
n
) are considered. We construct an infinite family of 2-uniform mappings in the binary case. In the nonbinary case we give
two large families of k-uniform mappings with low values of k. We also show how to construct families of sequences from differentially 1-uniform power mappings, which have parameters
as good as the best presently known comparable families of sequences.
Received: November 4, 1996; revised version: February 14, 1997 相似文献
4.
This paper addresses the application of Genetic Programming (GP) to the synthesis of multicomponent product nonsharp distillation
sequences. Combined with the domain knowledge of chemical engineering, some evolutionary factors are improved, and a set of
special encoding method and solving strategy is proposed to deal with this kind of problem. The system structural variable
is optimized by GP and the continuous variable is optimized by the simulated annealing algorithm simultaneously. Because GP
has an automatic searching function, the optimal solution can be found including distillation, splitting, blending and bypassing
operations automatically without any superstructures of nonsharp distillation sequences. Three illustrative examples are presented
to demonstrate the effective computational strategies. 相似文献
5.
Besides equidistribution properties and statistical independence the lattice profile, a generalized version of Marsaglia's
lattice test, provides another quality measure for pseudorandom sequences over a (finite) field. It turned out that the lattice
profile is closely related with the linear complexity profile. In this article we give a survey of several features of the
linear complexity profile and the lattice profile, and we utilize relationships to completely describe the lattice profile
of a sequence over a finite field in terms of the continued fraction expansion of its generating function. Finally we describe
and construct sequences with a certain lattice profile, and introduce a further complexity measure. 相似文献
6.
Alev Topuzoğlu Arne Winterhof 《Applicable Algebra in Engineering, Communication and Computing》2005,16(4):219-228
Nonlinear congruential methods are attractive alternatives to the classical linear congruential method for pseudorandom number
generation. Generators of higher orders are of interest since they admit longer periods. We obtain lower bounds on the linear
complexity profile of nonlinear pseudorandom number generators of higher orders. The results have applications in cryptography
and in quasi-Monte Carlo methods. 相似文献
7.
介绍攀钢冷轧厂酸轧机组出口段工艺及自动控制顺控的组成,全自动操作的原理、实现方法及在调试中对工艺、顺控的优化。 相似文献
8.
一种新的数字图像置乱方案* 总被引:6,自引:0,他引:6
提出了一种新的数字图像置乱概念和模型,采用了矩阵的配对及移位操作技术。配对的选择方式和移位次数决定于离散Chebyshev映射系统生成的密钥混沌序列。混沌系统的特性使得该置乱方法具有随机性和变化的多样性。讨论了置乱算法的安全性问题并给出了实验结果。 相似文献
9.
The accurate measurement of the execution time of Java bytecode is one factor that is important in order to estimate the total execution time of a Java application running on a Java Virtual Machine. In this paper we document the difficulties and solutions for the accurate timing of Java bytecode. We also identify trends across the execution times recorded for all imperative Java bytecodes. These trends would suggest that knowing the execution times of a small subset of the Java bytecode instructions would be sufficient to model the execution times of the remainder. We first review a statistical approach for achieving high precision timing results for Java bytecode using low precision timers and then present a more suitable technique using homogeneous bytecode sequences for recording such information. We finally compare instruction execution times acquired using this platform independent technique against execution times recorded using the read time stamp counter assembly instruction. In particular our results show the existence of a strong linear correlation between both techniques. 相似文献
10.