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1.
叙述了封闭式组合电器在不对称三相同壳母线结构下,快速瞬变过程三相电压测量的基本原理。在测量中需要3个电容传感器,每个传感器同时受A,B,C三相电压的电场耦合。三相电压与3个电容传感器输出电压之间的关系,可以用一个关系因子矩阵来表达,该矩阵是一个常数矩阵与电场耦合系数矩阵的乘积。通过分析电场耦合系数矩阵,提出了主导电场耦合系数的概念,并得到了它的近似解析表达式。根据电场耦合系数函数的特性,应分别将3个电容传感器安置于A,B,C三相导体在外壳上的近距点处,最后,给出了在一个不对称三相同壳母线模型上的快速瞬变过程三相电压实验测量结果。  相似文献   

2.
传感器优化配置的修正逐步累积法   总被引:11,自引:0,他引:11  
讨论了模态实验中传感器的配置问题。利用结构振型矩阵转置的QR分解得到传感器的初始配置。以模态置信度MAC矩阵的最大非对角元为目标函数,利用本文提出的修正逐步累积法得到传感器的配置,并提出传感器配置必须结合优化效果和经济性2方面综合考虑。  相似文献   

3.
基于分布式加权多维定标的节点自身定位算法   总被引:1,自引:0,他引:1  
提出了一种基于对称K最邻近(SKNN)传感器网络节点分布式精确定位算法.该算法首先采用SKNN方法选择每个节点的邻居节点,通过接收信号强度(RSS)方法测得每对节点之间的距离,构建节点距离矩阵,并以距离矩阵为输入,应用分布式多维加权算法对矩阵进行处理,从而获得传感器网络节点之间的局部映射关系.最后,根据参考节点的坐标对节点局部映射关系进行匹配,以获取节点坐标的全局映射.仿真实验表明,采用所提算法可以加强定位精度,提高计算效率,在有25个节点的传感器网络中,定位误差要比dwMDS方法低大约5%。  相似文献   

4.
提出了一种压电结构中作动/传感器优化配置的新方法.首先用有限元方法建立结构的动力学方程,并用模态方法进行降阶,然后通过Lyapunov方程分别求解扰动输入和作动器输入的能控性Grammian矩阵,通过使作动器输入的能控性矩阵向量在扰动能控性矩阵上投影长度的平方和最大值得到压电作动器的最优位置,同样的思想用于确定传感器的最优位置。  相似文献   

5.
给出了基于异质传感器的动态状态矢量融合算法,针对两个采用二维理想线性卡耳曼滤波器的异质传感器,对融合的互协方差矩阵的稳定性进行了分析,揭示了数据融合的本质。  相似文献   

6.
尹明  孙晓军 《山东科学》1998,11(4):53-56
在设计IC插座自动生产线中,计算机以传感器矩阵方式控制IC插座自动生产线的运行。以矢量方式控制电机、传感器的采样信号。整条生产线结构紧凑,操作简单,使用灵活,抗干扰能力强,常年运行可靠性高。  相似文献   

7.
本文讨论多维力传感器的两个普遍性的问题:标定及其试验设计。精密多维力传感器的标定就是辨识它的比刚度矩阵D和比柔度矩阵C。本文定义多维力传感器实验的品质指标和最优实验设计的准则,据此推导出多维力传感器结构参数所应满足的最优条件。  相似文献   

8.
结构健康监测传感器优化布置的混合算法   总被引:6,自引:1,他引:6  
提出了一种基于模型减缩和线性模型估计理论的、用于建筑结构健康监测中传感器布置的新算法.根据选定的主、从自由度,用改进减缩系统方法来减少初始结构的自由度数目.然后,基于线性模型估计,以所选定的目标模态为线性模型的设计矩阵,用奇异值分解处理设计矩阵.用分解后的前几个左奇异向量计算每一个自由度对于结构模态的贡献.最后用迭代算法来确定所需的传感器数量和位置.算例表明,此种混合算法适用于建筑结构监测的传感器布置计算.  相似文献   

9.
基于可观矩阵奇异值单元灵敏度的思想,提出了确定智能压电传感器安放位置的一种拓扑优化方法。为了获得智能结构压电传感器的优化位置,首先采用有限元方法对原系统进行了特征问题分析;第二利用奇异值分解法讨论了智能结构模态可观性的度量问题;第三推导了可观矩阵奇异值单元灵敏度公式;第四以奇异值单元灵敏度作为度量和准则并且给出一个门槛值,根据门槛值可以确定压电传感器优化位置;最后利用算例来说明本文方法的有效性。  相似文献   

10.
为了提高集中式多传感器一致性数据融合的精度,在数据融合过程中,必须考虑从各传感器获得的数据可信度.为了克服现有一致性数据融合算法中定义的距离矩阵和关系矩阵存在的不对称性和主观性等缺点,本文定义了概率距离矩阵和基于统计置信度的关系矩阵,然后讨论了多正态分布共同均值的极大似然估计的统计性质和递推特性,并根据估计量的方差统计性质提出了一种基于动态层次聚类的多传感器一致性数据融合处理的方法,数据实验的计算结果表明,该算法优于现有的多传感器一致性数据融合方法.  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.
<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   

20.
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