Calculating scaling function coefficients from system response data for new discrete wavelet families

2012 ◽  
Vol 27 ◽  
pp. 362-369 ◽  
Author(s):  
Andrew J. Dick ◽  
Quan M. Phan ◽  
Jason R. Foley ◽  
Pol D. Spanos
Keyword(s):  
Scaling Function ◽  
System Response ◽  
Discrete Wavelet ◽  
Response Data

Wavelet analysis on developable surface base on area preserving projection

2015 ◽  
Vol 13 (01) ◽  
pp. 1550007 ◽  
Author(s):  
Bao Qin Wang ◽  
Gang Wang ◽  
Xiao Hui Zhou ◽  
Yu Su
Keyword(s):  
Wavelet Transform ◽  
Discrete Wavelet Transform ◽  
Scaling Function ◽  
Discrete Wavelet ◽  
Developable Surface ◽  
Simple Method ◽  
Multi Resolution Analysis ◽  
Resolution Analysis ◽  
Area Preserving ◽  
The Scaling Function

In this paper, a simple method is given in order to construct an area preserving mapping from a developable surface M to a plane. Based on the area preserving projection, we give some important formulas on M, and define a multi-resolution analysis on L2(M). We provide the conditions to further discuss the continuous wavelet transform and discrete wavelet transform on developable surface. At the same time, we derived two-scale equations that the scaling function and wavelet function on developable surface satisfied, we also define and discuss the orthogonality, and several important theorems are given. Finally, we construct the numerical examples. The focus of this paper is the area preserving mapping that from developable surface M to a plane, and the discrete wavelet transform on developable surface.

scholarly journals METHOD FOR CONSTRUCTING NONLINEAR WAVELET CODE TO ENSURE DATA INTEGRITY IN COMMUNICATION CHANNELS

T-Comm ◽  
2021 ◽  
Vol 15 (2) ◽  
pp. 26-32
Author(s):  
Nikolay A. Kuznetsov ◽  
Keyword(s):  
Wavelet Transform ◽  
Wavelet Transforms ◽  
Scaling Function ◽  
Communication Channels ◽  
Data Integrity ◽  
Necessary Condition ◽  
Discrete Wavelet ◽  
Integrable Functions ◽  
Computational Calculations ◽  
Dynamic Stochastic

A method for constructing a nonlinear wavelet code (NVC) to ensure data integrity in communication channels, taking into account current threats to information security in a modern dynamic stochastic environment, is proposed. A special place among the methods of combating threats to the integrity of information is occupied by noise-resistant encoding. The article presents a computationally effective method for ensuring data integrity in communication channels by using nonlinear transformations and wavelets. The approximation of the wavelet transform refers to the division of the signal into approximating and detailing components. Continuous and discrete wavelet transforms are widely used [2] for signal analysis in modern communication channels. The set of functions defining the wavelet transform belongs to the space of square-integrable functions on a straight line and provides a necessary condition for constructing constructions of nonlinear codes based on the theory of wavelet decomposition. As is known, in the process of wavelet analysis, the signal is decomposed along the orthogonal basis formed by shifts of the wavelet function. A distinctive feature of this approach is that convolution of the signal with wavelets allows us to identify the characteristic features of the signal in the area of localization of these wavelets. To perform computational calculations, you need a set of scaling function coefficients and a wavelet. The wavelet transform matrix depends on the coefficients of the scaling function. The results presented in the article describe a new approach to ensuring data integrity in communication channels using nvcs. A computational example is presented.

Stochastic Linearization by Data Dependent Systems

1977 ◽  
Vol 99 (4) ◽  
pp. 221-226 ◽  
Author(s):  
S. M. Pandit
Keyword(s):  
Furnace Operation ◽  
System Response ◽  
Ticket Sales ◽  
Response Data ◽  
Machine Tool Chatter ◽  
Chatter Vibrations ◽  
Stochastic Linearization ◽  
Airline Passenger ◽  
Prediction And Control ◽  
And Control

The paper presents and illustrates a method of stochastic linearization of nonlinear systems. The system response to white noise excitation is modeled by a differential equation, which provides the necessary transfer function. The linearization is optimal in the mean squared sense within the statistical limits imposed by the response. Since the linearization is accomplished purely from the response data, governing equations of the system need not be known. An application to machine tool chatter vibrations illustrates stability assessment and modal analysis. The ease with which optimal prediction and control equations can be derived and implemented is shown by an application to blast furnace operation. Detection and verification of limit cycles are illustrated by a model for airline passenger ticket sales data.

scholarly journals PID-Based Design of DC Motor Speed Control

2021 ◽  
Vol 2 (1) ◽  
pp. 7
Author(s):  
Irfan Irhamni ◽  
Riries Rulaningtyas ◽  
Riky Tri Yunardi
Keyword(s):  
Transient Response ◽  
Pid Controller ◽  
Speed Control ◽  
Dc Motor ◽  
System Response ◽  
Motor Speed ◽  
Proportional Integral ◽  
Response Data ◽  
Dc Motors

DC motor is an easy-to-apply motor but has inconsistent speed due to the existing load. PID (Proportional Integral Differential) is one of the standard controllers of DC motors. This study aimed to know the PID controller's performance in controlling the speed of a DC motor. The results showed that the PID controller could improve the error and transient response of the system response generated from DC motor speed control. Based on the obtained system response data from testing and tuning the PID parameters in controlling the speed of a DC motor, the PID controller parameters can affect the rate of a DC motor on the setpoint of 500, 1000, 1500: Kp = 0.05, Ki = 0.0198, Kd = 0.05.

scholarly journals Forensic Engineering Analysis Of Trailer Sway Accidents

2008 ◽  
Vol 25 (1) ◽  
Author(s):  
Mark A.M. Ezra ◽  
Landiss Danel J.
Keyword(s):  
Data Reduction ◽  
Damping Ratio ◽  
Experimental System ◽  
Second Order ◽  
Coupled Systems ◽  
Order System ◽  
System Response ◽  
Statistical Validation ◽  
Response Data ◽  
Data Reduction Method

This Paper Describes A Method For The Reduction Of System Response Data For Second Order Electrical Or Mechanical Systems When That Data Is Available Only In Graphical Format. The Method Of Data Reduction Described Allows Quantitative Evaluation Of Generally Accepted Second Order System Parameters Such As: System Time Constant, Damped Natural Frequency, Damping Ratio, And Exponential Decay Time. The Discussion Includes The Application Of The Described Graphical Technique To Experimental System Response Data Of Coupled Systems, But Whose Experimental Response Approximates That Of An Isolated Second Order System. A Practical Application Of The Described Data Reduction Method Is Covered In Detail. The Described Technique Is Applied To The Analysis Of Data Obtained Experimentally For The Response Of A Tow Vehicle And Trailer System To A Standardized Steering Disturbance. Finally, The Statistical Validation For Experimental System Response Data And The Results Obtained From The Analysis Of Such Data, Using The Described Graphical Method, Is Discussed.

Identification of Multiple Damages in a Structure Using Embedded Sensitivity Functions and Optimization Techniques

2011 ◽  
Author(s):  
Chulho Yang ◽  
Douglas E. Adams
Keyword(s):  
Optimization Techniques ◽  
System Response ◽  
Story Structure ◽  
Response Data ◽  
Sensitivity Functions ◽  
Suggested Technique ◽  
Taylor Series Expansions ◽  
Measured Frequency Response ◽  
The Difference ◽  
Two Degree Of Freedom

A new method for identifying multiple damages in a structure using embedded sensitivity functions and optimization algorithms is presented in this work. Optimization techniques are used to minimize the difference between the measured frequency response functions from a damaged structure and the predicted FRFs from the baseline structure. The predicted FRF functions are calculated directly from the undamaged system response data using the embedded sensitivity functions and their Taylor series expansions. The optimal damage parameters are identified in engineering units as changes in stiffness, damping, or mass through the optimization process for minimizing the difference between those two FRFs. The method is applied to a two degree of freedom analytical model to determine the accuracy of the diagnostic results. Finite element analyses are then conducted on a three-story structure with damages in the form of stiffness and mass perturbations to demonstrate the applicability of this method to more complicated structural systems. It is shown that the suggested technique can detect and quantify multiple damages in a structure with high numerical accuracy in the level of the estimated damages.

scholarly journals Pressure drop test as a hydroinformatic tool for preliminary network topology validation

2018 ◽  
Vol 19 (2) ◽  
pp. 502-510
Author(s):  
M. Milašinović ◽  
D. Prodanović ◽  
M. Stanić
Keyword(s):  
Pressure Drop ◽  
Network Topology ◽  
Distribution Systems ◽  
Water Distribution ◽  
Pressure Change ◽  
Drop Test ◽  
System Response ◽  
Response Data ◽  
Reliable Model ◽  
Validation Tests

Abstract Usage of the appropriate model of water distribution systems (WDS) enables easier everyday operations and management decisions. Creating a reliable model of WDS requires a large amount of system response data for different case scenarios. Commonly used software for creating models of WDS is EpaNet. Ongoing processes in WDS, such as pipe bursts, permanently closed valves which are not registered in the data base and other inconsistencies will change WDS network topology, so WDS validation tests are to be applied from time to time. This paper presents the WDS network topology validation test conducted on one district metered area of Belgrade with two inflows. The pressure drop test combined with genetic algorithm and ant colony optimization are simple hydroinformatic tools available for network topology validation. The system's reaction under a pressure change during the isolation test was measured at two observation points. Obtained results are then compared with assumed WDS topology using 55 potential locations of inconsistencies in the EpaNet model. This step is repeated until a good enough match between results from the real system and the created model's version is obtained. Heuristic optimization algorithms are used for speeding up the process of finding a satisfactory match (unknown locations of inconsistencies) by minimizing or maximizing the defined criteria function.

Control of High Speed Milling Chatter in Simultaneous Time-Frequency Domain

2011 ◽  
Author(s):  
Meng-Kun Liu ◽  
C. Steve Suh
Keyword(s):  
Frequency Domain ◽  
Dynamic Stability ◽  
High Speed ◽  
Adaptive Controller ◽  
System Response ◽  
Discrete Wavelet ◽  
Line System ◽  
High Speed Milling ◽  
Time Frequency ◽  
Milling Chatter

The dynamics governing high speed milling has been extensively explored for decades, both numerically and experimentally. The process loses its dynamic stability and becomes chaotic through either Neimark-Sacker or period doubling bifurcation. While its associated response is still bounded in the time domain, however, it could become unstably broadband in the frequency domain, thus causing the uneven cutting surface on the workpiece and tool damage. A discrete-wavelet-based feedforward adaptive controller is developed to stabilize system response in the time and frequency domains simultaneously. An adaptive controller along with an adaptive filter effective for on-line system identification is implemented in the wavelet domain. By controlling both time and frequency responses, the presented controller design is demonstrated to effectively suppress milling chatter and restore the system back to dynamic stability.

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