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1.
根据不完全封闭n端输出顺序时序机的各种定义,建立了位状态差、序状态差、表状态差运算规律,构成了不完全状态差表及自状态差表,给出了不完全状态差表的一系列重要说明。不完全状态差表在海量数据块检测,模式识别,自然语言理解等方面有广泛应用。自状态差表可成功直观简明精确定不完全封闭n端输出顺序时序机隐式软故障。  相似文献   

2.
基于顺序时序机的数字集成系统隐式软故障自状态差定位   总被引:4,自引:2,他引:2  
建立隐式软故障概念。目前国内、国际在数字领域内极为关心的重大问题是它的精确定位,利用顺序时序机产生了全部工作模式下的样本状态表、状态差表,导出了基于顺序时序机状态差的一系列重要和特别有用的性质及规律,所形成的自状态差理论要比当前使用的故障诊断方法方便简单得多,用自状态理论极为容易对待测数字集成系统工作模式进行识别。同时直观地对隐式软故障精确定位,并可确定隐式软故障数目。自状态差法无疑将为数字集成系统设计及测试带来强有力支持。  相似文献   

3.
港口门机故障在线模糊综合识别的研究   总被引:1,自引:0,他引:1  
提出了门机动态监测中多种故障症候模糊综合识别法,并结合系统在线测得的数据样本,详细说明了门机动态监测专家系统对门机工作状态及故障识别的过程。  相似文献   

4.
目的 研究模拟回波对自差式连续波多普勒引信的干扰有效性。方法 应用非线性振荡理论分析了自差式连续波多普勒引信在真实回波与模拟回波作用下的工作状态。并对两种领事的作用特性进行了比较,结果 模拟回波作用下的自差机有3种工作状态;(1)H 能量条件均满足地,自差机处于牵引状态;(2)满足能量条件,但频率条件不满足时,模拟回波将自差引信的信号处理通带滤除;(3)满足频率条件,但能量太小时,也不能产生有效的  相似文献   

5.
提出一种时序Rough逻辑,定义了时序算子及其作用于Rough逻辑公式上的意义.描述了这种逻辑的语法和语义.论述了时序Rough逻辑中的语义模型是一个无限状态序列,其中每一状态都描述了当前时刻和场景点上信息系统的信息.从当前状态到下一状态的变换是遵循时序Rough逻辑演算的,它必须保持知识不变,也就是属性和讨论的对象不变,而属性关于对象的特征值,即属性值随着时间和场景变化而可以变化.因此。在信息系统上作决策、数据约简和信息粒化等都将产生影响,由此可见时序Rough逻辑将是动态地处理信息系统的理论工具,也将是合理地解决和处理不一致信息表的较好方法.  相似文献   

6.
为满足复杂系统的动态、实时和高可靠性的故障诊断需求,克服动态不确定因果图(dynamic uncertain causality graph,DUCG)及其他概率图模型的局限,该文在DUCG理论的基础上扩展其时序因果表达与推理方法,建立了立体DUCG(Cubic DUCG)理论模型。采用动态的手段处理动态问题,以"逐步生长"的立体因果建模取消了时序模型中常见的Markov假设限制,以穿越式因果连接准确地表达动态系统下故障的产生、演变和发展;直观地刻画和处理动态负反馈等复杂故障逻辑因果关系;给出了严谨、高效的动态推理算法。宁德核电站1号机组CPR1000模拟机二回路系统上的故障实验结果表明:Cubic DUCG诊断推理准确、高效,能有效处理负反馈等复杂动态情形。  相似文献   

7.
基于支持向量域描述的多故障诊断动态模型   总被引:2,自引:0,他引:2  
为了提高多故障诊断中对新故障类别和新故障数据的适应性,提出了一种新的多故障诊断动态模型.该模型采用支持向量域描述算法(SVDD)对多类故障进行单独训练,建立独立而封闭的特征空间,满足故障类别的动态增加需要,并采用样本与各特征空间的相对距离进行了多故障的混合识别.应用在线SVDD算法,在已有的故障特征分布信息基础上,通过更新操作,学习新数据信息,从而实现了故障模式的动态调整.通过仿真和机械故障实例数据的检验,表明该模型能够动态地提取多类故障的特征信息,改善诊断学习过程的适应性.  相似文献   

8.
飞机拉杆热收口机是公司军品生产的关键设备,它承担着生产系列直升机拉杆的收口工作,我公司的一台热牧口机存在设备故障率高,杆件收口成品合格率低,工作状态不稳定等一系列问题。为此,本文就拉杆在收口时产生偏差现象分析该炉头工作状态,提出解决方案,通过方案的实施,效果良好。  相似文献   

9.
应用矩阵模型,提出了一类非完全定义时序机的映射矩阵Ai和Bi的计算方法和状态相容条件,根据状态相容坏 出Pk划分,从而得到了该类时序机状态化简的算法。  相似文献   

10.
基于核的动态聚类算法用于机械故障模式分类   总被引:1,自引:0,他引:1  
针对k均值聚类对特征样本划分存在误分类的问题,提出用基于核的动态聚类算法对风机不同工作状态进行分类识别.实验结果表明,该方法能有效地识别机器运行的异常状态,并能对不同的故障模式进行正确的区分,可应用于机械设备运行状态的动态识别.  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.
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   

13.
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   

14.
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   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
Franck-Condon factors bridge the gap between theoretical modeling and experimental observations for molecular electronic spectroscopy and electron transfer.Under the displaced harmonic oscillator approximation,multidimensional Franck-Condon factors are decomposed into a product of many one-dimensional(1D)Franck-Condon(FC)factors,and each 1D-FC factor is associated with one Huang-Rhys factor that determines the leading contribution of  相似文献   

20.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

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