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Transmission line analogy model of left-handed metamaterials microstructure configuration
左手材料微结构构型的传输线比拟模型

Gao Ren-Jing,Shi Peng-Fei,Liu Shu-Tian,Duan Yu-Ping,Tang Zhen-An,
高仁璟
,史鹏飞,刘书田,段玉平,唐祯安

物理学报 , 2010,
Abstract: In this paper, based on the equivalent transmission line model a method of designing left-handed metamaterials micro-structures is proposed, verified and analyzed. Firstly, according to the basic transmission line model with left and right-handed characteristics, we build a new left-handed model by analogy. Then according to the qualitative analysis of the corresponding relationship of each component in the transmission line network to the shape and size of continuous medium micro-structure configuration, the specific size of model is inferred, and thus a reasonable left-handed metamaterials micro-structure configuration and the corresponding transmission line model are established. We have conducted a series of tests including numerical simulation, which verifies that there does exist the left-handed characteristic in a certain frequency band. Finally based on the numerical simulation and experiment the effects each micro-structural parameter on left-handed frequency position and bandwidth are analyzed, and the size parameter that affects the left hand characteristic most seriously is determined.
Transmission Line Analogy for Relativistic Poynting-Flux Jets  [PDF]
R. V. E. Lovelace,P. P. Kronberg
Physics , 2012, DOI: 10.1093/mnras/stt086
Abstract: Radio emission, polarization, and Faraday rotation maps of the radio jet of the galaxy 3C 303 have shown that one knot of this jet carries a {\it galactic}-scale electric current and that it is magnetically dominated. We develop the theory of magnetically dominated or Poynting-flux jets by making an analogy of a Poynting jet with a transmission line or waveguide carrying a net current and having a potential drop across it (from the jet's axis to its radius) and a definite impedance which we derive. Time-dependent but not necessarily small perturbations of a Poynting-flux jet are described by the "telegrapher's equations." These predict the propagation speed of disturbances and the effective wave impedance for forward and backward propagating wave components. A localized disturbance of a Poynting jet gives rise to localized dissipation in the jet which may explain the enhanced synchrotron radiation in the knots of the 3C 303 jet, and also in the apparently stationary knot HST-1 in the jet near the nucleus of the nearby galaxy M87. For a relativistic Poynting jet on parsec scales, the reflected voltage wave from an inductive termination or load can lead to a backward propagating wave which breaks down the magnetic insulation of the jet giving $|{\bf E}| /|{\bf B}|\geq 1$. At the threshold for breakdown, $|{\bf E}|/|{\bf B}|=1$, positive and negative particles are directly accelerated in the ${\bf E \times B}$ direction which is approximately along the jet axis. Acceleration can occur up to Lorentz factors $\sim 10^7$. This particle acceleration mechanism is distinct from that in shock waves and that in magnetic field reconnection.
Study of parametric sensitivity of the general model of transmission line  [PDF]
Kaoutar Senhaji Rhazi,Mohamed Najmouddine
International Journal of Computer Science Issues , 2012,
Abstract: In reference to two articles previously published in the annals of telecommunications journal from; which we will quote a summary in the following paragraph, this paper provides a study of the parametric sensitivity of the transmission lines general model. Indeed, we know that the modeling project of a shielded line subject to current disruption, in any position of its length, involves several factors. Some of these factors have a major influence on the assessment of parasitic tensions; others have lesser importance. So, it is necessary to identify the effect produced on the result by each of them to perform a parametric study. This latter helps clarify some of the instructions on the previous articles about the differences that occur between calculations and measurements at high frequencies.
Maxwell’s Equations as the Basis for Model of Atoms  [PDF]
Milan Perkovac
Journal of Applied Mathematics and Physics (JAMP) , 2014, DOI: 10.4236/jamp.2014.25029
Abstract: A century ago the classical physics couldn’t explain many atomic physical phenomena. Now the situation has changed. It’s because within the framework of classical physics with the help of Maxwell’s equations we can derive Schrödinger’s equation, which is the foundation of quantum physics. The equations for energy, momentum, frequency and wavelength of the electromagnetic wave in the atom are derived using the model of atom by analogy with the transmission line. The action constant A0 = (μ0/ε0)1/2s02e2 is a key term in the above mentioned equations. Besides the other well-known constants, the only unknown constant in the last expression is a structural constant of the atom s0. We have found that the value of this constant is 8.277 56 and that it shows up as a link between macroscopic and atomic world. After calculating this constant we get the theory of atoms based on Maxwell’s and Lorentz equations only. This theory does not require knowledge of Planck’s constant h, which is replaced with theoretically derived action constant A0, while the replacement for the fine structure constant α-1 is theoretically derived expression 2s02 = 137.036. So, the structural constant s0 replaces both constants h and α. This paper also defines the stationary states of atoms and shows that the maximal atomic number is equal to Zmax = 137. The presented model of the atoms covers three of the four fundamental interactions, namely the electromagnetic, weak and strong interactions.
A Simple Modified Transmission Line Model for Inset Fed Antenna Design  [PDF]
M. Fawzi Bendahmane,Mehadji Abri,Fethi Tarik Bendimerad,Noureddine Boukli-Hacene
International Journal of Computer Science Issues , 2010,
Abstract: In this paper we propose the design of single inset fed printed antenna based on a simple modified transmission line model. The developed model is simple, accurate and takes into account all antenna characteristics and their feed system. To test the proposed model, the obtained results are compared to those obtained by the moment's method (Agilent Momentum software). Using this transmission line approach the resonant frequency, input impedance, return loss can be determined simultaneously. The paper reports several simulation results that confirm the validity of the developed model. The obtained results are then presented and discussed.
Determination of the Structural Constant of the Atom  [PDF]
Milan Perkovac
Journal of Applied Mathematics and Physics (JAMP) , 2014, DOI: 10.4236/jamp.2014.23002
Abstract:

The equations for energy, momentum, frequency, wavelength and also Schr?dinger equation of the electromagnetic wave in the atom are derived using the model of atom by analogy with the transmission line. The action constant A0 = (μ0/ε0)1/2s02e2 is a key term in the above mentioned equations. Besides the other well-known quantities, the only one unknown quantity in the last expression is a structural constant s0. Therefore, this article is dedicated to the calculation of the structural constant of the atoms on the basis of the above mentioned model. The structural constant of the atoms s0 = 8.277 56 shows up as a link between macroscopic and atomic world. After calculating this constant we get the theory of atoms based on Maxwells and Lorentz equations only. This theory does not require Planck constant h, which once was introduced empirically. Replacement for h is the action constant A0, which is here theoretically derived, while the replacement for fine structure constant α is 1/(2s02). In this way, the structural constant s0 replaces both constants, h and α. This paper also defines the stationary states of atoms and shows that the maximal atomic number is equal to 2s02 = 137.036, i.e., as integer should be Zmax=137. The presented model of the atoms covers three of the four fundamental interactions, namely the electromagnetic, weak and strong interactions.

Model of Three-Phase Transmission Line with the Theory of Modal Decomposition Implied  [PDF]
Rodrigo Cleber da Silva, Sérgio Kurokawa
Energy and Power Engineering (EPE) , 2013, DOI: 10.4236/epe.2013.54B217
Abstract:

This paper shows the development of transmission line model, based on lumped element circuit that provides answers directly in the time and phase domain. This model is valid to represent the ideally transposed line, the phases of each of the small line segments are separated in their modes of propagation and the voltage and current are calculated at the modal domain. However, the conversion phase-mode-phase is inserted in the state equations which describe the currents and voltages along the line of which there is no need to know the user of the model representation of the theory in the line modal domain.

The modeling of UPFC based on circuit elements in an exact transmission line model  [PDF]
Ali akbar Motie birjandi & Kauomars Sabzawari
International Journal of Engineering , 2010,
Abstract: UPFC is considered and known as one of the best FACTS devices. It is acombination of series and parallel quick compensation, and can thereforeprovide active and reactive control to achieve maximum power transfer, systemstability and improve power quality and reliability. Therefore, presenting asuitable model for UPFC which enables studying the network and load flow inenergy transmission lines, has gotten the experts’ attention. This paper presentsa new model of UPFC in steady state based on circuit elements in an exacttransmission line model. Considering the fact that the elements like UJT andtunnel diode in negative resistance region cause power increase, the modeldetermines the value of the active and reactive power injected by the seriesconverter into the network, and then the series converter of UPFC is simulatedby means of a negative resistor and an induction or capacitor reactance.Resistance and reactance are expressed as functions of voltage of buses, loadangle, voltage injection and fire angle of series converter. The relations of thismodel have been achieved in a two-bus system and have been simulated in 14-and 30- bus standard.
Existence of periodic solutions for the nonlinear functional differential equation in the lossless transmission line model

Wang Na,

中国物理 B , 2012,
Abstract: We study a time delay equation for the lossless transmission line model. Under suitable conditions, by using the continuation theorem of the coincidence degree theory, the existence of the periodic solution for the nonlinear functional differential equation is obtained.
Bi-Band Bow-Tie Antennas Array Design Using a Simple Equivalent Transmission Line Model  [PDF]
M. Abri,H. Abri Badaoui,H. Dib,A.S.E. Gharnaout
International Journal of Computer Networks & Communications , 2012,
Abstract: In this paper we propose a simple equivalent and accurate transmission line model for bi-band bow-tie antennas array design over a band of frequencies for satellite communications. This model uses the resistance of a square element that appears at the edges of the antenna (radiating slots). To test this model, two antennas array were simulated and results were compared with those obtained by a rigorous method (moment’s method) of the simulator ADS/Momentum. Using this transmission line approach the resonant frequency, return loss, VSWR, reflected phase, input impedance can be determined simultaneously. The results confirm the validity of the proposed model.
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