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1.
讨论了一类非线性系统观测器的构造方法 .对仿射非线性系统观测器的条件进行了讨论 ,给出了必要的假设 ,得到与原系统微分同胚的系统 (简称同胚系统 ) ,并保持仿射性不变 .对同胚系统观测器给出了适当定义 ,它表现为一个模型系统 ,并根据其输出与同胚系统输出间的误差进行修正 .给出并论证了同胚系统状态观测器的构造方法 ,其关键是选择与模型系统和同胚系统间输出误差有关的增益矩阵 .对原系统 ,只要寻求与同胚系统间的一个适当变换 ,即可实现原系统的状态观测器 .参 6 .  相似文献   

2.
基于Riemann-Liouville导数的分数阶Birkhoff系统,提出了用积分因子理论寻找分数阶Birkhoff系统的守恒量的一种新思路.先由分数阶Birkhoff系统方程,给出了其积分因子的定义;其次,建立了由该系统积分因子理论得到的该系统守恒定理.为了进一步得到该系统的守恒量,给出了分数阶Birkhoff系统的广义Killing方程.分数阶Hamilton系统的守恒定理为本文特例.最后,举例说明结果的应用.  相似文献   

3.
随着网络技术的发展,电子政务系统也在网上广为应用.针对某市公安局电子政务系统系统资源不能共享等问题,运用软件工程和数据库理论,研制了新公安电子政务系统.介绍了其特点、作用与功能.给出了系统的设计和实现方法及有关的软件程序.运行结果证明了系统的可靠性.  相似文献   

4.
工业通讯专网互联传统的方式是使用专用的通讯汇接设备,这种方式投资大,系统复杂.文章从实际情况出发,提出一种使用调度系统替代汇接设备的方案.主要论述了调度系统应用于工业企业汇接系统的可行性、设计思想、实现方法.这种应用方案简化了整体系统,节约了成本.实际使用证明这种汇接系统简化了系统的结构,节约了投资,具有很好的实用性.  相似文献   

5.
根据自主移动机器人实时导航的需要,提出了一种基于CAN总线的移动机器人声纳数据采集系统.针对自主移动机器人的工作特点,利用CAN总线技术,设计了多声纳传感器的数据采集系统.实现了机器人数据采集的网络化,降低了系统的连线数量,提高系统的可维护性.同时确定了该系统和工控机之间的CAN总线通信协议,并给出了系统硬件框图和软件流程图.实验表明,该系统具有较高的实用价值及较高的可靠性、实时性.  相似文献   

6.
提出了一个新的延迟分数阶系统.首先,对该延迟系统随延迟项变化的动力学进行了研究;然后,基于分数阶系统的稳定性理论,提出了该系统的同步方案.通过设计合适的同步控制器,实现了系统的同步.数值仿真验证了同步方案的有效性.  相似文献   

7.
一类区间切换系统的鲁棒稳定性   总被引:1,自引:1,他引:0  
讨论了一类区间切换系统的鲁棒稳定性.区间切换系统是一类含有不确定参数的切换系统.作为一个切换系统,标称系统的稳定性决定了这类区间切换系统的鲁棒稳定性.充分利用结构特点,通过标称系统各部分的稳定性获得这类系统的鲁棒稳定性.当标称系统的各子系统均渐近稳定时,给出区间切换系统在任意切换下渐近稳定的条件.进一步,在标称系统的各子系统都不渐近稳定的情形下,利用凸组合技术,讨论了实现区间切换系统在某一切换律下的渐近稳定性.  相似文献   

8.
构造了一个新的结构简单的三维连续自治混沌系统,该系统含有两个参数和两个非线性项.利用Matlab软件给出了系统处于混沌态时的相图、时间历程、功率谱、Poincaré映射、Lyapunov指数和分形维数.通过Lyapunov指数谱和分岔图分析了系统参数对该系统的影响.研究结果证实了该系统是新混沌系统,揭示了该系统具有丰富的动力学特性.  相似文献   

9.
介绍了NSRL二期工程中束流测量系统的改造,包括DCCT测量系统、闭轨测量系统、基于束流准直系统、工作点测量系统、光位置测量系统和200 MeV直线加速器能谱测量系统.这些测量系统为合肥光源的运行调试和机器研究提供了有效的手段.另外,还给出了这些系统的应用和测量结果.  相似文献   

10.
研究了一个四维分数阶新系统的隐藏吸引子.在特定条件下,此系统有一条平衡点线或无平衡点.同时讨论了系统平衡点的稳定性,证明了不同类型的隐藏吸引子.进一步通过调整系统参数和系统初始值,利用分岔图、相图得到了新系统的共存隐藏吸引子,分析了系统的复杂动力学行为,并设计了同步控制器,实现了此系统的组合同步,数值仿真结果验证了同步控制方案的有效性.  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.
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   

15.
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   

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.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

19.
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   

20.
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   

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