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In this paper, a novel class of normal realizations for discrete-time systems is derived and characterized. It is shown that these realizations are free of self-sustained oscillations and yield a minimal error propagation gain. The optimal realization problem, defined as to find those normal realizations that minimize roundoff noise gain, is solved analytically. Based on Schur-form, a procedure is...
In this paper, we propose a new method of time-scale modification (TSM) of audio signal. In the proposed GWSOLA algorithm, we introduce the gain control into the standard WSOLA technique which could adjust the level of the audio segments for overlap and add in order to maintain the audio signal level consistent. We perform a time-scale modification (TSM) using a waveform similarity overlap-add (WSOLA)...
Motivated by the operational need of eliminating the potential single point of failure (SPOF) of a communications network, a cooperative team communication (CTC) approach is proposed for distributed, wireless sensor and team networks. We assume that the communication system uses a spread spectrum waveform, and each radio implements the Rake processing capability to combat channel fading effects. The...
Simulink is one of the most widely used industrial tools to design embedded systems. Applying formal methods sooner in the cycle of development is an important industrial challenge in order to reduce the cost of bug fixing. In this article, we introduce a new method, called abstract simulation and based on abstract interpretation of Simulink models. Abstract simulation uses several numerical domains...
The oscillator, inherently, turns the phase noise of its internal components into frequency noise, which results into a multiplication by 1/f2 in the phase-noise power spectral density. This phenomenon is known as the Leeson effect. This article extends the Leeson effect to the analysis of amplitude noise. This is done by analyzing the slow-varying complex envelope, after freezing the carrier. In...
A ray optics based statistical multipath channel model has been developed to describe the indoor multipath propagation including the important parameters such as path gain, time-of-arrival, angle-of-arrival and number of multipath components. Development of such a model is crucial for performance evaluation of indoor positioning systems. Based on a comprehensive ray-tracing database obtained on the...
This paper presents a new approach to rejection of sinusoidal disturbances acting at the output of a discrete-time complex-valued linear stable plant (e.g. acoustic channel) with unknown and possibly time-varying dynamics. It is assumed that the instantaneous frequency of the sinusoidal disturbance may be slowly varying with time and that the output signal is contaminated with wideband measurement...
The nonlinear PI parameter adjustment method by RBFN was considered in this research. When the decision of the parameter of the controlled object with a nonlinear characteristic changed the target value by doing by RBFN, an excellent result was obtained. The adjustment method of the intermediate value of the hidden layer of this RBFN is scheduled to be considered in the future.
Firstly, the flow fields downstream one axisymmetric nozzles and a nozzle with four tabs were simulated with four different turbulent models, and the results were compared with experimental data. Then the flow fields downstream nozzles with tabs of varied orientation angles were predicted for different orientation angles of the tabs while the projected blockage of tabs was kept unchanged. The predictions...
This paper studies the bifurcation behavior of the probe tip of an atomic force microscope with a proportional-plus-derivative (PD) feedback control using the DT (differential transformation) method. The dynamic behavior of the probe tip with PD control law is characterized by reference to maximum Lyapunov exponent plots produced using the time-series data obtained from differential transformation...
This paper presents an adaptive control design method for a class of multi-input multi-output uncertain nonlinear systems. It is shown that the proposed controller has guaranteed transient and steady state performance in the presence of parametric and non-parametric uncertainties and bounded disturbances. The approach guarantees arbitrary close tracking of the states and state derivatives of a given...
Generalized predictive control (GPC) achieves a robust tracking for step-type reference signal by including an integrator in advance. Although author has proposed a design scheme of two degree-of-freedom GPC system which reveals an effect of integral compensation only if there exists modeling error or disturbance, a gain for integral compensation must be selected by trial and error. In this paper,...
In this paper, a new tuning method of the multi-loop PID controller for loop shaping is proposed. The loop shaping problem of maximizing the integral gain of the PID controller under the maximum sensitivity constraint is reduced to a linear programming problem. The constraints on the PID gains are directly derived from many data obtained by filtering the plant responses with many bandpass filters...
This paper deals with robust control problem of an electropneumatic system subjected to parameters uncertainties and load disturbances. The control strategies are based on passivity control approaches. First, the nonlinear model of the electropneumatic system is presented. Then, a nonlinear control law is developed without depending on the mass of the carriage, to track desired position. Experimental...
The paper details the application and handling qualities evaluation through computer-based simulation of an adaptive model reference controller acting on the longitudinal modes of a fighter-type aircraft. Whereas classical control designs depend largely on a priori knowledge of the system dynamics, adaptive control algorithms do not require the same degree of a priori sophistication, or alternately...
A parametric study of a wide-band Vivaldi antenna is presented. Four models were simulated using a finite element method design and analysis package Ansoft HFSS v 10.1. The simulated return loss and realized gain of each model for a frequency range of 12 to 20 GHz is studied. The location of the phase centre, represented as the distance d (in cm) from the bottom of the antenna, with respect to which...
The TWT mathematical model on wavy bent rectangular waveguide is described taking into account losses and dielectric filling of a waveguide. Features of formation of TWT frequency characteristics in submillimeter range are noted. The reasons of TWT self-excitation are analyzed and methods of its suppression are offered.
In system LSIs, costs of analog circuits are getting increased relatively for rapid cost reduction of digital circuits. To satisfy given specifications in the analog design, including low power and small area, designers have to select an optimal solution among large combination of the following alternatives: which architecture should be adopted; what type of transistors should be taken; and whether...
In present work we aimed to develop a NN based approach to translate the design parameter from a submicron technology to a long channel one. The proposed approach is able to find the superseded design parameters in 1.2 mum technology using the input information, which are design parameters of Gain, Phase Margin, Unity Gain Bandwidth and Power in TCMS 0.18 mum. The training data are obtained by various...
The Authors present a new approach of finding out unreasonable activity loops. The approach was named as SRM (string reachable matrix) which intended to analyze business processes effectively. This matrix stemmed from reachable matrix and could show activity loops and paths directly in elements of the matrix. The definition, operating rules of SRM and others related to SRM were also described in this...
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