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101.
Sliding mode control problem of a class of Ito type partial differential equations with delay is probed. The variable structure controller is designed. The existence of motion of sliding mode is shown. And the character of invariance of sliding control system about uncertainty on the sliding switching surface and stability are analyzed.  相似文献   
102.
The expected value and generating function of the number of overlapping occurrences of a pattern P in a Markov chain until the first occurrence of a member from a finite collection of patterns that start with P is obtained. A martingale technique is employed to address the problem.   相似文献   
103.
IntroductionTheductile brittletransition (DBT )ofsteelalloysisinfluencedbythematerialmicrostructureandtestingtemperature[1].Availablereferencesrangingfromanalyticalapproachtoempiricaltestsaretoonumeroustolist.Mostofthesemodesaredeterministic ,whichdidnottaketherandomnessoftheparametersandman_madeerrorintoconsideration .Thebasicproposesofthispaperistounderstandthetransitionbyanewrandom_fuzzymodel.Theductile brittletransitioninvolvestheductilefracture ,brittlefractureandthetransition .Inacerta…  相似文献   
104.
Mathematical foundation of a new complexity measure   总被引:4,自引:0,他引:4  
For many continuous bio-medieal signals with both strong nonlinearity and non-stationarity, two criterions were proposed for their complexity estimation : (1) Only a short data set is enough for robust estimation; (2) No over-coarse graining preproeessing, such as transferring the original signal into a binary time series, is needed. Co complexity measure proposed by us previously is one of such measures. However, it lacks the solid mathematical foundation and thus its use is limited. A modified version of this measure is proposed, and some important properties are proved rigorously. According to these properties, this measure can be considered as an index of randomness of time series in some senses, and thus also a quantitative index of complexity under the meaning of randomness finding complexity. Compared with other similar measures, this measure seems more suitable for estimating a large quantity of complexity measures for a given task, such as studying the dynamic variation of such measures in sliding windows of a long process, owing to its fast speed for estimation.  相似文献   
105.
Summary: In order to investigate the influence of reactivity ratios and initial feed composition on the microstructure of macromolecules in free radical copolymerization, a comprehensive study was carried out using a Monte Carlo simulation method. As a result, a new procedure was introduced to modify the works of others on the initiation step. The variation of the copolymer composition and the fashion of the arrangement of monomers in simulated chains were evaluated as a function of copolymerization parameters. The model was capable of monitoring any change in azeotropy as well as the magnitude and direction of composition drift from the azeotrope point. The maximum reachable conversion (MRC) was predicted for different combinations of initial feed compositions and reactivity ratios. According to the simulation results, a critical conversion where the macromolecules produced inherited the maximum allowed alternation was obtained for the reactivity ratios given.

Change of sequence distribution of simulated copolymer chains with conversion for various initial feed compositions on a triangular graph (rA = 0.5, rB = 0.9).  相似文献   

106.
从探究物理机制的视角对混凝土疲劳研究进行了逻辑上的梳理,表明既有研究可分为3 类主要模型:基于疲劳试验分析的现象学模型、基于断裂力学的疲劳裂纹扩展模型和基于损伤力学的疲劳损伤演化模型. 通过解析具有典型性的研究,论述了不同类型研究的特点. 进而,从还原论的角度出发,阐明了速率过程理论可以作为解释混凝土材料疲劳损伤演化的物理基础. 注意到疲劳试验结果所表现出的显著随机性,阐述了应以物理随机系统思想研究混凝土疲劳问题的观点.  相似文献   
107.
Recently Lloyd and Zurek studied the algorithmic complexity of the spin-echo effect and concluded that the overall complexity of spins together with the magnetic field grew slowly even during the rephasing stage. In this paper we show that, in contrast to their conclusion, the complexity decreases during the rephasing stage. We also clarify the origin of the disagreement.  相似文献   
108.
We examine the randomness and triviality of reals using notions arising from martingales and prefix‐free machines. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
109.
The primary aim of this paper is to expose the use and the value of spatial statistical analysis in business and especially in designing economic policies in rural areas. Specifically, we aim to present under a unified framework, the use of both point and area‐based methods, in order to analyze in‐depth economic data, as well as, to drive conclusions through interpreting the analysis results. The motivating problem is related to the establishment of women‐run enterprises in a rural area of Greece. Moreover, in this article, the spatial scan statistic is successfully applied to the spatial economic data at hand, in order to detect possible clusters of small women‐run enterprises in a rural mountainous and disadvantaged region of Greece. Then, it is combined with Geographical Information System based on Local Indicator of Spatial Autocorrelation scan statistic for further exploring and interpreting the spatial patterns. The rejection of the random establishment of women‐run enterprises and the interpretation of the clustering patterns are deemed necessary, in order to assist government in designing policies for rural development. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
110.
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