Rashba control to minimize circuit cost of quantum Fourier algorithm in ballistic nanowires

2019 ◽  
Vol 383 (12) ◽  
pp. 1247-1254
Author(s):  
A.H. Homid ◽  
M.R. Sakr ◽  
A.-B.A. Mohamed ◽  
M. Abdel-Aty ◽  
A.-S.F. Obada
Keyword(s):  
Fourier Algorithm

The extended Fourier algorithm: Application in discrete optics and electron holography

1994 ◽  
Vol 52 ◽  
pp. 918-919
Author(s):  
E. Voelkl ◽  
L. F. Allard
Keyword(s):  
Fourier Transform ◽  
Fourier Transforms ◽  
Sampling Rate ◽  
Electron Holography ◽  
Optical Bench ◽  
Fourier Space ◽  
Ccd Cameras ◽  
Simulated Image ◽  
Initial Sampling ◽  
Fourier Algorithm

The conventional discrete Fourier transform can be extended to a discrete Extended Fourier transform (EFT). The EFT allows to work with discrete data in close analogy to the optical bench, where continuous data are processed. The EFT includes a capability to increase or decrease the resolution in Fourier space (thus the argument that CCD cameras with a higher number of pixels to increase the resolution in Fourier space is no longer valid). Fourier transforms may also be shifted with arbitrary increments, which is important in electron holography. Still, the analogy between the optical bench and discrete optics on a computer is limited by the Nyquist limit. In this abstract we discuss the capability with the EFT to change the initial sampling rate si of a recorded or simulated image to any other(final) sampling rate sf.

Practical Tools for Reasoning About Linear Constraints

1991 ◽  
Vol 15 (3-4) ◽  
pp. 357-379
Author(s):  
Tien Huynh ◽  
Leo Joskowicz ◽  
Catherine Lassez ◽  
Jean-Louis Lassez
Keyword(s):  
Logic Programming ◽  
Intelligent Systems ◽  
Optimization Problem ◽  
Spatial Reasoning ◽  
Quantifier Elimination ◽  
Canonical Representation ◽  
Linear Constraints ◽  
Practical Applications ◽  
Variable Elimination ◽  
Fourier Algorithm

We address the problem of building intelligent systems to reason about linear arithmetic constraints. We develop, along the lines of Logic Programming, a unifying framework based on the concept of Parametric Queries and a quasi-dual generalization of the classical Linear Programming optimization problem. Variable (quantifier) elimination is the key underlying operation which provides an oracle to answer all queries and plays a role similar to Resolution in Logic Programming. We discuss three methods for variable elimination, compare their feasibility, and establish their applicability. We then address practical issues of solvability and canonical representation, as well as dynamical updates and feedback. In particular, we show how the quasi-dual formulation can be used to achieve the discriminating characteristics of the classical Fourier algorithm regarding solvability, detection of implicit equalities and, in case of unsolvability, the detection of minimal unsolvable subsets. We illustrate the relevance of our approach with examples from the domain of spatial reasoning and demonstrate its viability with empirical results from two practical applications: computation of canonical forms and convex hull construction.

Thermal Overload Protection for AC Asynchronous Motor Based on Complex Morlet Wavelet

2015 ◽  
Vol 740 ◽  
pp. 364-367
Author(s):  
Su Wang ◽  
Lei Sun ◽  
Wei Cong Huang
Keyword(s):  
Asynchronous Motor ◽  
Morlet Wavelet ◽  
Algorithm Analysis ◽  
Full Wave ◽  
Overload Protection ◽  
Dc Component ◽  
Complex Morlet Wavelet ◽  
Fourier Algorithm ◽  
Wavelet Algorithm ◽  
Better Than

Conventionally, the fault signal of motor thermal overload in a non-periodic component is not effectively filtered with Full-wave Fourier Algorithm (or FFA). In this paper, a design which combined Complex Morlet Wavelet Algorithm with Subtraction (or CMWAS) filter is presented. The design gives system model of overload and algorithm analysis It is verified that the new algorithm is better than the FFA algorithm in terms of filtering decaying DC component.

Interdiffusion in MBE-Grown Symmetrically and Asymmetrically Strained Si/Si1−xGex Superlattices Investigated by Ion Scattering

1992 ◽  
Vol 263 ◽  
Author(s):  
B. Holländer ◽  
R. Butz ◽  
S. Mantl
Keyword(s):  
Thermal Annealing ◽  
Rapid Thermal Annealing ◽  
Rutherford Backscattering Spectrometry ◽  
Buffer Layers ◽  
Arrhenius Law ◽  
Ion Scattering ◽  
Strained Si ◽  
The Individual ◽  
Interdiffusion Coefficients ◽  
Fourier Algorithm

ABSTRACTThe interdiffusion in MBE-grown Si/Si1−xGex superlattices was measured by Rutherford backscattering spectrometry. The superlattices consisted of 5 periods of 100 !A Si and 100 !A Si1−xGex layers with Ge concentrations, x, between 0.20 and 0.70. Both, asymmetrically strained superlattices, grown on Si(100), as well as symmetrically strained superlattices, grown on relaxed Si1−y.Gey buffer layers were investigated. Rapid thermal annealing in the temperature range between 900°C and 1125°C leads to significant interdiffusion between the individual layers, indicated by a decrease of the amplitudes of the backscattering spectra. Interdiffusion coefficients were deduced using a Fourier algorithm. The interdiffusion coefficients follow an Arrhenius law for a given Ge concentration. The interdiffusivity increases significantly with increasing Ge concentration.

Simulation of Supercontinuum Generation by Using Modified Split-Step Fourier Algorithm

2009 ◽  
Vol 36 (8) ◽  
pp. 2046-2051
Author(s):  
崔秀艳 Cui Xiuyan ◽  
赵建林 Zhao Jianlin ◽  
杨德兴 Yang Dexing ◽  
李鹏 Li Peng ◽  
赵卫 Zhao Wei ◽  
...  
Keyword(s):  
Supercontinuum Generation ◽  
Fourier Algorithm

Research and Improvement of Fourier Algorithm in the Microcomputer Relay Protection

2013 ◽  
Vol 347-350 ◽  
pp. 1945-1948
Author(s):  
Jian Xu ◽  
Xin Yao
Keyword(s):  
Power System ◽  
Harmonic Component ◽  
Relay Protection ◽  
High Accuracy ◽  
Computer Algorithms ◽  
Full Wave ◽  
Dc Component ◽  
Fourier Algorithm ◽  
Improved Algorithm ◽  
Microcomputer Relay Protection

Fourier algorithm can be effective utilized in the Microcomputer relay protection to filter out Harmonic component in the AC signal .but the drawback is that not filter attenuation DC component. it may be affect the computation accuracy of the entire system .and it is also reduce the efficiency of the system. In this paper ,we combined with the actual project ,on the basis of analysis of the full-wave Fourier algorithm ,for the problem of it can not filter decaying a periodic component ,we proposed an improved algorithm, and combined with MATLAB simulation ,the results show that the improved algorithm has the advantages of high accuracy and the algorithm is simple. In the microcomputer relay protection of the power system need to handle all kinds of signals, provide the necessary information for the implementation of protection. however, With the rapid development of computer technology and the continuous research of computer algorithms, a lot of actual power system protection device has been widely used in our life, on the one hand, these devices reduce the complexity of building hardware circuit, on the other hand ,it can make full use of the filter function about some algorithms have itself. The most important is that it can avoid the problem of instability and low efficiency with some filter circuit. But, this characteristic need the algorithms has a high precision [2,3]. The algorithm is set up in the microcomputer protection is a mathematical model for achieve some specific function. and write the corresponding computer applications according to this model. Then do some specific mathematical operations with these digital signals will achieve the purpose of protection. At present, the widely used full wave Fourier algorithm has a function of filtering DC component and harmonic component[4],but it can not filtering the decaying DC component in the system. It will be cause a certain interference and influence to the whole system in the practical application, the result is that led to the precision of the operation drop and lose the meaning of the protecting. In this paper, combined with specific engineering example give an improved calculation method. Through example of simulation has proved that using this algorithm can accurately figure out fundamental component and harmonic component, and it has the advantage of algorithm simple and high accuracy [5].

SNOCRAFT: A Learning-Oriented Shorthand Notation for Creating, Representing, and Analyzing Fast Fourier Transform Algorithms

1980 ◽  
Vol 17 (3) ◽  
pp. 284-284
Author(s):  
Robert J. Meir ◽  
Sathyanarayan S. Rao
Keyword(s):  
Fourier Transform ◽  
Fast Fourier Transform ◽  
Fourier Transforms ◽  
Reduced Form ◽  
Fast Fourier Transform Algorithm ◽  
Signal Flow Graph ◽  
Shorthand Notation ◽  
The Matrix ◽  
Fourier Algorithm ◽  
Fft Analysis

This paper presents a full and well-developed view of the Fast Fourier Transform (FFT). It is intended for the reader who wishes to learn and develop his own fast Fourier algorithm. The approach presented here utilizes the matrix description of fast Fourier transforms. This approach leads to a systematic method for greatly reducing the complexity and the space required by variety of signal flow graph descriptions. This reduced form is called SNOCRAFT. From this representation, it is then shown how one can derive all possible fast Fourier transform algorithms, including the Weinograd Fourier transform algorithm. It is also shown from the SNOCRAFT representation that one can easily compute the number of multiplications and additions required to perform a specified fast Fourier transform algorithm. After an elementary introduction to matrix representation of fast Fourier transform algorithm, the method of generating all possible fast Fourier transform algorithms is presented in detail and is given in three sections. The first section discusses the Generation of SNOCRAFT and the second section illustrates how Operations on SNOCRAFT are made. These operations include inversion and rotation. The last section deals with the FFT Analysis. In this section, examples are provided to illustrate how one counts the number of multiplications and additions involved in performing the transform that one has developed.

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