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排序方式: 共有383条查询结果,搜索用时 15 毫秒
41.
CHEN Shennian Department of Electronic Engineering Huaqiao University Quanzhou China 《中国科学G辑(英文版)》2005,48(3):300-318
1 Introduction Historically, circuit theory was initially considered as a part of the electromagnetic theory. Later on, it branched out to become an independent theory. After several stages of its development, Kirchhoff’s law was commonly regarded as the fundamental law of circuits[1]. Especially after the 1960s, the completely topological formulation of Kirchhoff’s law made even more important contribution to the development of moderncircuit theory. However, it has been also known for a l… 相似文献
42.
Luigi Fortuna Mattia Frasca Salvatore Graziani Salvatore Reddiconto 《Nonlinear dynamics》2006,44(1-4):55-61
In this paper, the possibility of observing strange attractors in an electronic circuit including a nonlinear ferroelectric
component has been investigated. The ferroelectric constitutes the medium interposed between the two plates of a capacitor.
A circuit including the nonlinearity of the ferroelectric has been designed, while the parameters have been found by performing
numerical integration with respect to different values of them. The circuit has been realized on a discrete components board.
Experimental results, showing that for a suitable range of parameters a chaotic attractor emerges, are reported. 相似文献
43.
44.
施绍裘 《宁波大学学报(理工版)》1988,(1)
采用传输线理论可以计算机械式UHF调谐器对应不同频率点的调谐电容量。在进行满足直线频率关系的调谐电容片形设计时,应当求出调谐电容量C_Τ与旋转角θ的显式函数关系。但对于分布参数的电路,这有一定的困难。本文采用数值计算方法完成了具有良好直线频率跟踪特性的调谐电容片形的设计,并由计算机自动绘出了片形。 相似文献
45.
M.H. Hecht A.J. Viescas I. Lindau J.W. Allen L.I. Johansson 《Journal of Electron Spectroscopy and Related Phenomena》1984,34(4):343-353
We report on the four-peak structure observed in the region of 4f photoemission in Yb metal, using synchrotron radiation in the energy range 70–200 eV. We conclude, contrary to previous reports, that the doublet associated with surface emissions results from an intrinsic surface shift on clean regions of the surface. We also demonstrate that the observed structure is consistent with earlier XPS measurements, and we set an upper limit on the width of the bulk peaks. 相似文献
46.
47.
We prove that in a tournament of odd order , the number of antidirected Hamiltonian paths starting with a forward arc and the number of Hamiltonian circuits have the same parity. 相似文献
48.
Stasys Jukna 《Discrete Mathematics》2010,310(1):184-187
A boolean circuit represents an n by n(0,1)-matrix A if it correctly computes the linear transformation over GF(2) on all n unit vectors. If we only allow linear boolean functions as gates, then some matrices cannot be represented using fewer than Ω(n2/lnn) wires. We first show that using non-linear gates one can save a lot of wires: any matrix can be represented by a depth-2 circuit with O(nlnn) wires using multilinear polynomials over GF(2) of relatively small degree as gates. We then show that this cannot be substantially improved: If any two columns of an n by n(0,1)-matrix differ in at least d rows, then the matrix requires Ω(dlnn/lnlnn) wires in any depth-2 circuit, even if arbitrary boolean functions are allowed as gates. 相似文献
49.
M. Prochaska F. A. Probst W. Mathis 《Mathematical and Computer Modelling of Dynamical Systems: Methods, Tools and Applications in Engineering and Related Sciences》2013,19(6):531-543
Emitter-coupled multivibrators play a decisive role in electrical engineering, especially for phase locked loops which are key-building blocks of analogue RF front-ends. Since multivibrators correspond to relaxation oscillators, in the following the modelling and analysis by the theory of singularly perturbed systems is presented. Models for fast and slow phenomena are derived, and the fast transients of emitter-coupled multivibrators are analysed for the first time. The results of our analysis lead to significant advantages for the design of electrical multivibrators. 相似文献
50.
S. Sabarathinam K. Thamilmaran L. Borkowski P. Perlikowski P. Brzeski A. Stefanski T. Kapitaniak 《Communications in Nonlinear Science & Numerical Simulation》2013,18(11):3098-3107
The dynamics of two coupled, dissipatively perturbed, near-integrable Hamiltonian, double-well Duffing oscillators has been studied. We give numerical and experimental (circuit implementation) evidence that in the case of small positive or negative damping there exist two different types of transient chaos. After the decay of the transient chaos in the neighborhood of chaotic saddle we observe the transient chaos in the neighborhood of unstable tori. We argue that our results are robust and they exist in the wide range of system parameters. 相似文献