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1.
本文建立了广义系统解耦控制问题与正常系统相应问题的等价条件,从而更一般而深入地研究了这个问题.给出了广义系统在状态反馈、输出反馈和动态补偿下解耦的充要条件,描述了反馈律中系数阵的特征及补偿器的设计方法.还深入讨论了解耦系统能控能观性及其它性质,并给出了数值实例.  相似文献   

2.
健合图模型是描述动态物理系统的一种新的图示模型.通过该模型很容易得到系统的状态空间描述。特别适宜于系统的数字仿真.本文以一个典型的随动系统的实例说明了该方法的建模过程及其仿真.其结果表明该建模过程及仿真简单、可靠.  相似文献   

3.
本文论述步长联控式数据自动采集原理和数据处理方法,提出拟合直线与拟合曲线在联接点处保持连续与相切的一种实用方法,给出了与另外二种拟合方法的对比图形,列出了这三种不同回归方法的优缺点及适用范围.本方法已成功地应用于材料的拉伸试验、断裂韧性K_(IC)测试及σ_(0.2)系列(诸如σ_(0.1),σ_(0.5)等)的微机自动测试.  相似文献   

4.
本文以T.Shedlovsky法为例,对电导法测定离解常数的经典数据处理方法进行了改进,通过计算机的应用,大大地减少了实验工作量,简化了数据处理过程,使结果变得更为准确、可靠。  相似文献   

5.
本文讨论动态投入产出分析中的线性集结问题.对于具有多年时滞环节的动态投入产出经济系统,在原系统的最终产品作为外生变量即控制变量时。通过所构造的二次型性能指标,求出了使原系统的最终产品尽可能满足已规划的最终产品量时,集结偏差最小的条件.  相似文献   

6.
本文提出了一个适用于计算机程控扫描等离子体发射光谱仪的谱线选择的新方法及相应的计算机程序,实验结果表明该方法准确、快速、经济、方便,具有一定的实用价值.  相似文献   

7.
从Einstein引力场理论的Schwarzschild解出发,根据经典规范场理论构造了Schwarzschild场的规范势、场强,计算了场的外源流、守恒的外源流和自源流,讨论了场的化约条件和自对偶性.  相似文献   

8.
本文对常用炸药在ODS柱上的保留行为进行了系统研究,初步揭示了它们的变化规律,为炸药混合样品的快速分离分析提供了理论依据.  相似文献   

9.
金相图象特征信息提取是进行金相分析的关键.本文在分析金相图象的区域和边缘(晶界)二类特征信息基础上,指出采用基于熵概念的图象阈值化技术可实现区域特征提取.用微分算子实现边缘(晶界)提取后,采用适合晶界及网状结构的滤波方法进行滤波,从而实现边缘(晶界)的准确提取,并通过实验验证了上述方法的有效性.  相似文献   

10.
本文运用信息量负熵原理给出了热力学第二定律的信息论表示式——孤立系的信息量减少原理.把热力学观点和信息论观点结合起来进一步阐述了热力学第二定律的本质.通过对单原子理想气体的扩散问题的简单讨论,结合Shanonn的信息量公式,定量地说明了热力学第二定律的熵增加原理和信息量减少原理两种表述的一致性.本文还应用信息量减少原理为光速c作为极限速率提供了一种新的论证方法.  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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

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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