properties of discrete time fourier transform pdf

... on the “freezing” technique for discrete- time systems. This method has been used to investigate properties as well as to the construction of solutions for systems of linear Rigoberto Medina 3 It ... stability of time- dependent difference equations in Banach spaces,” Journal of the Institute of Mathematics and Its Applications, vol. 14, no. 3, pp. 335–346, 1974. 11 S. Zhang, “Estimate of total ... majo- rants. Based on the “freezing” technique to discrete- time systems, we derive explicit conditions for the absolute stability of the zero solution of such systems. Copyright q 2008 Rigoberto Medina....

Ngày tải lên: 22/06/2014, 06:20

... Trong miền tần số: phương pháp Fourier Transform. - Trong miền thời gian và tần số: STFT( Short Time Fourier Transform) . 2.4.1. Phương pháp Fourier: 2.4.1.1. Biến đổi Fourier: Cho một hàm f(t) ... triển chuỗi Fourier của F(t) () () = = k tjk ekFtf 0 (2.18) vi () () = 2 2 0 1 T T tjk dtetf T kF ã Phân tích liên tục: PDF created with pdfFactory Pro trial version www.pdffactory.com ... kết thúc của sự kiện thì Fourier không phát hiện được. 2.4.2. Phương pháp STFT: Để đạt được một biến đổi Fourier cục bộ, chúng ta có thể định nghĩa một biến đổi Fourier cửa sổ. Tín hiệu đầu...

Ngày tải lên: 01/04/2013, 16:14

... infinite set of possible signals is converted into a finite set. The next step of encoding maps the finite set of discrete time, continuous amplitude signals into a finite set of discrete time, discrete amplitude ... as its domain. A discrete time, continuous amplitude signal has R as its range. A discrete time, discrete amplitude signal has Z as its range. Here, the focus is on discrete time signals. Quantization ... discrete time signals. Quantization is the process of approximating any discrete time, continuous amplitude signal into one of a finite set of discrete time, continuous amplitude signals based on a particular...

Ngày tải lên: 18/10/2013, 04:15

... terms of efficiency of communication. 2 Principles of Content Selection in the Real Time Discourse 2.1 Maximization of Total Information A discourse is most effective when the amount of information ... effectively address the problem of when-to-say any piece of information. However, in MIKE we have only an implicit model of when-to-say. Rather, a collection of game analysis modules and ... piece of information directly affect the importance of the remaining unuttered comments. To separate these processes cause significant time delays that would not be tolerable in our time- critical...

Ngày tải lên: 20/02/2014, 18:20

... compared with those of flavin derivatives. The retention time of the prosthetic group bound to recom- binant flavoredoxin was identical to that of FMN (Fig. S3). The A 448 : A 268 ratio of the holoprotein ... both of which confer reduction of a flavin by receiving elec- trons from NADH or NADPH; however, these activi- ties of flavoredoxin were much lower than those of A. fulgidus FeR. The FeR activity of ... linear regression analysis of the logarithms of the concentration ratios for oxidized and reduced forms of the mediator versus that of recombinant flavoredoxin. Reduction titration of flavoredoxin by NAD(P)H The...

Ngày tải lên: 07/03/2014, 02:20

... http://www.translational-medicine.com/content/7/1/41 Page 6 of 10 (page number not for citation purposes) Diagram of the kinetics of wound closure (A)Figure 3 Diagram of the kinetics of wound closure (A). VEGF 165 and QK accelerate the closure of ... evalu- ation of data were performed using GraphPad Prism ver- sion 5.01 (GraphPad Software, San Diego, California, USA). Results Properties of QK were first assessed in ex vivo experiments of vascular ... proangiogenic properties of QK, suggesting that also in vivo this peptide resembles the full VEGF protein. These data open to new fields of investigation on the mechanisms of activation of VEGF receptors,...

Ngày tải lên: 18/06/2014, 15:20

... paper. 2 Simplified Fractional Fourier Transform (FrFT) The FrFT is a generalizatio n of regular Fourier trans- form in that the Fourier transform transforms a signal from time- domain to frequency-domain, ... fractional Fourier transform and time- frequency representations. IEEE Transactions on Signal Processing 42 (10), 3084–3091 (1992) 21. SC Pei, JJ Ding, Simplified fractional Fourier transform. ... μ)du. (3) Given that F is the Fourier transform operator and F α r is the fractional Fourier transform operator, then the FrFT possesses the following important properties. 1) Zero rotation: F 0 r =...

Ngày tải lên: 20/06/2014, 22:20

... nonlinear optical properties of semi-spherical quantum dots Jefferson Flórez * and Ángela Camacho Abstract We study the excitonic effects on the second-order nonlinear optical properties of semi-spherical ... from few nanometers to tens of nanometers. We find that the second-order nonlinear coefficients exhibit not only a blue-shift of the order of meV but also a change of intensity compared with the ... eigenstates of Hamiltonian (8) by a finite elements method for the two frequencies mentioned above. We have used the soft- ware COM-SOL Multiphysics, which offers the possibi- lity of defining...

Ngày tải lên: 21/06/2014, 04:20

... The porosity of the nanowires is restricted by etchant concentration, etching time and doping lever of the silicon wafer. The diffusion of silver ions could lead to the nucleation of silver nanoparti- cles ... H 2 O 2 concentration of 0.3 M, but different etching times from 30 min to 3 h. The morphology of these SiNWs is sum- marized in Fig. 2. The variable morphology of the SiNWs with etching time is similar ... lengths of the porous SiNWs depend on a H 2 O 2 concentrations and b etching times Nanoscale Res Lett (2010) 5:1822–1828 1825 123 times. As the increase in the H 2 O 2 concentrations or etching times,...

Ngày tải lên: 21/06/2014, 08:20

... introduced, such as the wavelet transform, the Wigner-Ville distribution, the Radon-Wigner transform, and the Fractional Fourier transform. Fractional Fourier transform, as a new time- frequency analysis ... take advantage of the special characteristics of speech. In this work, we show that the representation of the time- varying properties of speech may benefit from using the values of pitch and formants ... and fractional Fourier transform, ” Transactions of Beijing Institute of Technology, vol. 23, no. 3, pp. 371–377, 2003. [39] Y. R. Chao, Ed., A Grammar of Spoken Chinese, University of California...

Ngày tải lên: 21/06/2014, 20:20

... 2, pp. 521–542, 1999. 10 E. K. Boukas, “State feedback stabilization of nonlinear discrete- time systems with time- varying time delay,” Nonlinear Analysis: Theory, Methods & Applications, ... for discrete- time systems,” IEEE Transactions on Automatic Control, vol. 41, no. 6, pp. 903–907, 1996. 12 E. N. Chukwu, Stability and Time- Optimal Control of Hereditary Systems, vol. 188 of ... the global exponential stabilizability of discrete- time systems with time- delayed states. Finally, as an application, we consider the global stabilization of the nonlinear control systems. 2. Preliminaries In...

Ngày tải lên: 21/06/2014, 20:20

... representation. Of these modes, the ones that transform according to C t ẳ A 1 ẩ E 1 ẩ E 2 (the tensor representation) or C v are Raman- or IR-active, respectively. Out of the 12 N modes, four (which transform as ... T R2 to a 2 . An example of each type of BC 2 N nanotubes is given in Fig. 1b–f. Symmetry of BC 2 N Nanotubes We first consider the achiral carbon nanotubes with the rotation axis of order n, i.e., zigzag ... symmetries at the C point of the 12 N (N is the number of unit cells in the tube and N = n for ZZ-1 BC 2 N nanotubes) of phonons in ZZ-1 BC 2 N nanotubes and the number of Raman- or IR-active modes,...

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