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1.
研究了Lurie混沌系统的脉冲控制同步问题,基于Lyapunov稳定性理论和矩阵不等式处理方法,将Lurie混沌系统的同步化问题转化为线性矩阵不等式来处理,便于实现.  相似文献   

2.
将组合同步和函数投影同步相结合,研究了由3个混沌驱动系统和2个混沌响应系统组成的驱动—响应系统的组合函数投影同步问题.首先给出组合函数投影同步的定义,将驱动—响应系统的同步问题转化为误差系统零解的稳定性问题;然后基于Lyapunov稳定性理论和自适应控制方法,设计了非线性反馈同步控制器及参数自适应律,使得混沌驱动—响应系统按照相应的函数尺度因子矩阵实现同步;最后以Lorenz混沌系统、Chen混沌系统、Lü混沌系统作为驱动系统,以Tesi混沌系统、R?ssler混沌系统作为响应系统,通过数值仿真验证了该同步控制方案的有效性.  相似文献   

3.
研究了离散Lurie系统以及离散不确定Lurie系统的混沌同步问题,基于Lyapunov稳定性理论,得到在控制律的适当选取下,Lurie混沌系统是同步的这一结论。数值算例说明了该方法的有效性。  相似文献   

4.
研究Lurie混沌系统的有限时间同步问题,同时考虑Lurie系统及其不确定系统、Lurie观测器系统及其不确定系统的有限时间同步问题,给出一个易于实现的连续非线性反馈控制器,并根据有限时间稳定性理论,指出当该控制器满足一定条件时,2个相同的Lurie系统可以快速达到有限时间同步,基于Lyapunov稳定性理论给出系统有限时间同步的充分条件,并估计出同步时间.最后数值算例说明该方法的有效性.  相似文献   

5.
以稳定性理论为基础,针对Lorenz混沌系统,采用非线性反馈控制方法,通过设计合适的控制器,研究了该系统的改进的混合投影同步(MFSHPS)问题。理论分析证明了该控制器可以使Lorenz混沌系统达到混合投影同步,数值仿真证明了该控制方法的有效性。  相似文献   

6.
利用标准的线性符号函数替换了Lorenz-Stenflo(LS)混沌系统的一个非线性项,重构得到了一个新的四维混沌系统,命名为修正的Lorenz-Stenflo(MLS)混沌系统.简化的结构使得该系统易于用电子线路实现.接着根据线性系统稳定性理论,结合非线性反馈控制方法,提出了MLS系统的广义投影同步方法.理论推导得到了2个MLS混沌系统实现广义投影同步的稳定条件.改进的投影同步控制器具有多个可变参数,可以自由设定系统的同步速度和同步形式.该方法适用范围广,应用灵活,简单易于实现.仿真结果验证了同步控制器可在多种同步形式下实现2个MLS混沌系统的广义同步,动态过程误差小.  相似文献   

7.
针对Rikitake混沌系统,以稳定性理论为基础,采用非线性反馈控制方法,通过设计合适的控制器,研究该系统改进的全状态混合投影同步(MFSHPS)问题。理论分析证明该控制器可以使Rikitake混沌系统达到投影同步。数值仿真结果表明该控制方法有效。  相似文献   

8.
针对不确定参数的分数阶混沌系统的同步问题,提出了一种自适应混合函数投影同步设计方案.基于分数阶系统稳定性理论,设计自适应控制器和参数更新律,实现分数阶Lorenz混沌系统的混合函数投影同步,并完成对响应系统所有不确定参数的辨识.数值仿真验证了该控制器和参数更新规则的有效性和正确性.  相似文献   

9.
讨论了3D混沌系统的反同步.基于Lyapunov稳定性理论,运用Active控制方法选择控制函数,将混沌系统的反同步问题转化为同步误差系统在原点的渐进稳定性问题,实现了3D混沌系统的反同步,最后用数值模拟验证了方法的有效性。  相似文献   

10.
基于自适应技巧研究了分数阶Like-Bao混沌系统滑模同步,构造出一种整数阶滑模函数和自适应规则,取得了分数阶Like-Bao混沌系统自适应滑模同步的充分条件,进而得出分数阶Like-Bao混沌系统在符合一定条件下可取得自适应滑模同步的结论.  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

20.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

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