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排序方式: 共有329条查询结果,搜索用时 234 毫秒
61.
The diffusion process of point particles moving on regular triangular and random lattices, randomly occupied with stationary scatterers (a Lorentz lattice gas cellular automaton), is studied, for strictly deterministic scattering rules, as a function of the concentration of the scatterers. In addition to the normal and various kinds of retarded diffusion found before on the regular square lattice, straight-line propagation through the scatterers is observed. 相似文献
62.
Erica Jen 《Journal of statistical physics》1986,43(1-2):219-242
63.
本文提出了一个从随机到确定性的变测度算法,通过对不同的箱子采用不同的测度,将Monte-Carlo随机投点与确定性数论方法相结合的策略,使水平值充分地下降.最后,给出了实现算法收敛性并通过数值实验验证了其有效性. 相似文献
64.
65.
Max-Olivier Hongler Halil Mete Soner Ludwig Streit 《Applied Mathematics and Optimization》2004,49(2):113-121
We construct the explicit connection existing between a solvable model of the discrete velocities non-linear Boltzmann equation and the Hamilton-Bellman-Jacobi equation associated with a simple optimal control of a piecewise deterministic process. This study extends the known relation that exists between the Burgers equation and a simple controlled diffusion problem. In both cases the resulting partial differential equations can be linearized via a logarithmic transformation and hence offer the possibility to solve physically relevant non-linear field models in full generality. 相似文献
66.
A recent trend in local search concerns the exploitation of several different neighborhoods so as to increase the ability
of the algorithm to navigate the search space. In this work we investigate a hybridization technique, that we call Neighborhood Portfolio Approach, that consists in the interleave of local search techniques based on various combinations of neighborhoods. In particular,
we are able to select the most effective search technique through a systematic analysis of all meaningful combinations built
upon a set of basic neighborhoods. The proposed approach is applied to two practical problems belonging to the timetabling
family, and systematically tested and compared on real-world instances. The experimental analysis shows that our approach
leads to automatic design of new algorithms that provide better results than basic local search techniques. 相似文献
67.
Very High-Speed True Random Noise Generator 总被引:1,自引:0,他引:1
Ada Fort Fabrizio Cortigiani Santina Rocchi Valerio Vignoli 《Analog Integrated Circuits and Signal Processing》2003,34(2):97-105
In this work an original CMOS implementation of a discrete-time deterministic-chaos algorithm for random bit generation is presented. The proposed circuit topology prevents the degradation of the generated-sequence statistical properties that can be caused by several factors, including the parameter spreading of the technological processes. Experimental results show that, with a final rate of 3 Mbit/s, the circuit is compliant with the most recent security requirements for cryptographic modules issued by the American National Institute of Standards and Technologies. 相似文献
68.
确保信息物理融合系统(Cyber-Physical System,CPS)运行时行为正确性是至关重要的,尤其在航空航天、汽车、核电和医疗等安全攸关领域.本文针对具有随机行为且状态不可观测的CPS,提出一种基于隐马尔科夫模型的运行时安全性验证方法.首先构造状态不可观测的CPS运行时安全性验证框架,该框架通过隐马尔科夫模型表示系统,使用确定性有限自动机规约系统安全属性的否定,两者的乘积自动机作为运行时监控器,从而将CPS运行时安全性验证问题约简到监控器上的概率推断问题.然后,提出一种增量迭代安全性验证算法以及反例生成算法.实验结果表明本文算法和粒子滤波算法相比预测错误率下降了近20%,并且当系统违背安全属性时,本文的方法能给出反例. 相似文献
69.
A deterministic global optimization method is described for identifying the global minimum potential energy conformation of oligopeptides. The ECEPP/3 detailed potential energy model is utilized for describing the energetics of the atomic interactions posed in the space of the peptide dihedral angles. Based on previous work on the microcluster and molecular structure determination [21, 22, 23, 24], a procedure for deriving convex lower bounding functions for the total potential energy function is developed. A procedure that allows the exclusion of domains of the (ø, ) space based on the analysis of experimentally determined native protein structures is presented. The reduced disjoint sub-domains are appropriately combined thus defining the starting regions for the search. The proposed approach provides valuable information on (i) the global minimum potential energy conformation, (ii) upper and lower bounds of the global minimum energy structure and (iii) low energy conformers close to the global minimum one. The proposed approach is illustrated with Ac-Ala4-Pro-NHMe, Met-enkephalin, Leu-enkephalin, and Decaglycine. 相似文献
70.
Rodrigue Byrne 《Journal of Electronic Testing》1997,11(3):263-272
The aliasing probability (AP) of a Built-In Self-Test (BIST)architecture is the probability that an error response gets classified as agood response. A general technique to determine the AP for many common andalternative BIST response analysis (RA) architectures is presented here.This technique models the RA circuit as a Deterministic Finite Automaton(DFA), and determines the AP by counting the ratio of strings accepted bythe DFA to the total number of possible error strings. The strings acceptedby a DFA can be calculated by counting the paths in the DFAs statetransition graph (STG). Moreover, if the STG is complete, then theAP(k) = ((1/N)Nk-1)/(Nk-1), where k is the testlength and N is the number of states and input symbols. Thistechnique is demonstrated by determining the APs for the following RAarchitectures: Multiple-Input Shift Registers (MISRs), Cellular Automata(CA), Linear Feedback Shift Registers (LFSRs), accumulators, and a set ofalternative architectures directly based on DFAs. This paper also shows howthe adjacency matrix of the STG can be used to directly determine the AP ofany RA architecture modeled as a DFA. Finally, the eigenvalues andeigenvectors of the DFAs STG adjacency matrix are used to derive generalexpressions for the DFAs AP. 相似文献