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Research on the Digitial Image Based on Hyper-Chaotic And
Research on digital image watermark encryption based on hyperchaos Item Type Thesis or dissertation Authors Wu, Pianhui Publisher University of Derby Download date 27/09/2021 09:45:19 Link to Item http://hdl.handle.net/10545/305004 UNIVERSITY OF DERBY RESEARCH ON DIGITAL IMAGE WATERMARK ENCRYPTION BASED ON HYPERCHAOS Pianhui Wu Doctor of Philosophy 2013 RESEARCH ON DIGITAL IMAGE WATERMARK ENCRYPTION BASED ON HYPERCHAOS A thesis submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy By Pianhui Wu BSc. MSc. Faculty of Business, Computing and Law University of Derby May 2013 To my parents Acknowledgements I would like to thank sincerely Professor Zhengxu Zhao for his guidance, understanding, patience and most importantly, his friendship during my graduate studies at the University of Derby. His mentorship was paramount in providing a well-round experience consistent with my long-term career goals. I am grateful to many people in Faculty of Business, Computing and Law at the University of Derby for their support and help. I would also like to thank my parents, who have given me huge support and encouragement. Their advice is invaluable. An extra special recognition to my sister whose love and aid have made this thesis possible, and my time in Derby a colorful and wonderful experience. I Glossary AC Alternating Current AES Advanced Encryption Standard CCS Combination Coordinate Space CWT Continue Wavelet Transform BMP Bit Map DC Direct Current DCT Discrete Cosine Transform DWT Discrete Wavelet Transform -
Do Chaos-Based Communication Systems Really Transmit Chaotic Signals?
Signal Processing 108 (2015) 412–420 Contents lists available at ScienceDirect Signal Processing journal homepage: www.elsevier.com/locate/sigpro Do chaos-based communication systems really transmit chaotic signals? Renato Candido a, Diogo C. Soriano b, Magno T.M. Silva a,n, Marcio Eisencraft a a University of São Paulo, Brazil b Universidade Federal do ABC, Brazil article info abstract Article history: Many communication systems based on the synchronism of chaotic systems have been Received 2 May 2014 proposed as an alternative spread spectrum modulation that improves the level of privacy Received in revised form in data transmission. However, depending on the map and on the encoding function, the 24 September 2014 transmitted signal may cease to be chaotic. Therefore, the sensitive dependence on initial Accepted 2 October 2014 conditions, which is one of the most interesting properties for employing chaos in Available online 14 October 2014 telecommunications, may disappear. In this paper, we numerically analyze the chaotic Keywords: nature of signals modulated using a system that employs the Ikeda map. Additionally, we Chaos propose changes in the communication system in order to guarantee that the modulated Nonlinear systems signals are in fact chaotic. Chaos-based communication systems & 2014 Elsevier B.V. All rights reserved. Ikeda map Attractors 1. Introduction diverges from the original one. These three properties all together are necessary for a signal to be called chaotic Non-linear systems and chaos have been applied in all and are the basis for the alleged advantages of using chaos areas of engineering [1]. This fact is particularly true when in communications, as an improvement in security [15]. -
Lecture 9: Newton Method 9.1 Motivation 9.2 History
10-725: Convex Optimization Fall 2013 Lecture 9: Newton Method Lecturer: Barnabas Poczos/Ryan Tibshirani Scribes: Wen-Sheng Chu, Shu-Hao Yu Note: LaTeX template courtesy of UC Berkeley EECS dept. 9.1 Motivation Newton method is originally developed for finding a root of a function. It is also known as Newton- Raphson method. The problem can be formulated as, given a function f : R ! R, finding the point x? such that f(x?) = 0. Figure 9.1 illustrates another motivation of Newton method. Given a function f, we want to approximate it at point x with a quadratic function fb(x). We move our the next step determined by the optimum of fb. Figure 9.1: Motivation for quadratic approximation of a function. 9.2 History Babylonian people first applied the Newton method to find the square root of a positive number S 2 R+. The problem can be posed as solving the equation f(x) = x2 − S = 0. They realized the solution can be achieved by applying the iterative update rule: 2 1 S f(xk) xk − S xn+1 = (xk + ) = xk − 0 = xk − : (9.1) 2 xk f (xk) 2xk This update rule converges to the square root of S, which turns out to be a special case of Newton method. This could be the first application of Newton method. The starting point affects the convergence of the Babylonian's method for finding the square root. Figure 9.2 shows an example of solving the square root for S = 100. x- and y-axes represent the number of iterations and the variable, respectively. -
The Newton Fractal's Leonardo Sequence Study with the Google
INTERNATIONAL ELECTRONIC JOURNAL OF MATHEMATICS EDUCATION e-ISSN: 1306-3030. 2020, Vol. 15, No. 2, em0575 OPEN ACCESS https://doi.org/10.29333/iejme/6440 The Newton Fractal’s Leonardo Sequence Study with the Google Colab Francisco Regis Vieira Alves 1*, Renata Passos Machado Vieira 1 1 Federal Institute of Science and Technology of Ceara - IFCE, BRAZIL * CORRESPONDENCE: [email protected] ABSTRACT The work deals with the study of the roots of the characteristic polynomial derived from the Leonardo sequence, using the Newton fractal to perform a root search. Thus, Google Colab is used as a computational tool to facilitate this process. Initially, we conducted a study of the Leonardo sequence, addressing it fundamental recurrence, characteristic polynomial, and its relationship to the Fibonacci sequence. Following this study, the concept of fractal and Newton’s method is approached, so that it can then use the computational tool as a way of visualizing this technique. Finally, a code is developed in the Phyton programming language to generate Newton’s fractal, ending the research with the discussion and visual analysis of this figure. The study of this subject has been developed in the context of teacher education in Brazil. Keywords: Newton’s fractal, Google Colab, Leonardo sequence, visualization INTRODUCTION Interest in the study of homogeneous, linear and recurrent sequences is becoming more and more widespread in the scientific literature. Therefore, the Fibonacci sequence is the best known and studied in works found in the literature, such as Oliveira and Alves (2019), Alves and Catarino (2019). In these works, we can see an investigation and exploration of the Fibonacci sequence and the complexification of its mathematical model and the generalizations that result from it. -
Lecture 1: What Is Calculus?
Math1A:introductiontofunctionsandcalculus OliverKnill, 2012 Lecture 1: What is Calculus? Calculus formalizes the process of taking differences and taking sums. Differences measure change, sums explore how things accumulate. The process of taking differences has a limit called derivative. The process of taking sums will lead to the integral. These two pro- cesses are related in an intimate way. In this first lecture, we look at these two processes in the simplest possible setup, where functions are evaluated only on integers and where we do not take any limits. About 25’000 years ago, numbers were represented by units like 1, 1, 1, 1, 1, 1,... for example carved in the fibula bone of a baboon1. It took thousands of years until numbers were represented with symbols like today 0, 1, 2, 3, 4,.... Using the modern concept of function, we can say f(0) = 0, f(1) = 1, f(2) = 2, f(3) = 3 and mean that the function f assigns to an input like 1001 an output like f(1001) = 1001. Lets call Df(n) = f(n + 1) − f(n) the difference between two function values. We see that the function f satisfies Df(n) = 1 for all n. We can also formalize the summation process. If g(n) = 1 is the function which is constant 1, then Sg(n) = g(0) + g(1) + ... + g(n − 1) = 1 + 1 + ... + 1 = n. We see that Df = g and Sg = f. Now lets start with f(n) = n and apply summation on that function: Sf(n) = f(0) + f(1) + f(2) + .. -
Fractal Newton Basins
FRACTAL NEWTON BASINS M. L. SAHARI AND I. DJELLIT Received 3 June 2005; Accepted 14 August 2005 The dynamics of complex cubic polynomials have been studied extensively in the recent years. The main interest in this work is to focus on the Julia sets in the dynamical plane, and then is consecrated to the study of several topics in more detail. Newton’s method is considered since it is the main tool for finding solutions to equations, which leads to some fantastic images when it is applied to complex functions and gives rise to a chaotic sequence. Copyright © 2006 M. L. Sahari and I. Djellit. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, dis- tribution, and reproduction in any medium, provided the original work is properly cited. 1. Introduction Isaac Newton discovered what we now call Newton’s method around 1670. Although Newton’s method is an old application of calculus, it was discovered relatively recently that extending it to the complex plane leads to a very interesting fractal pattern. We have focused on complex analysis, that is, studying functions holomorphic on a domain in the complex plane or holomorphic mappings. It is a very exciting field, in which many new phenomena wait to be discovered (and have been discovered). It is very closely linked with fractal geometry, as the basins of attraction for Newton’s method have fractal character in many instances. We are interested in geometric problems, for example, the boundary behavior of conformal mappings. In mathematics, dynamical systems have become popular for another reason: beautiful pictures. -
Efficient Method for Detection of Periodic Orbits in Chaotic Maps And
Efficient Method for Detection of Periodic Orbits in Chaotic Maps and Flows A Thesis by Jonathan Crofts in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Department of Mathematics University of Leicester March 2007. c Jonathan J Crofts, 2007. arXiv:0706.1940v2 [nlin.CD] 13 Jun 2007 Acknowledgements I would like to thank Ruslan Davidchack, my supervisor, for his many suggestions and constant support and understanding during this research. I am also thankful to Michael Tretyakov for his support and advice. Further, I would like to acknowledge my gratitude to the people from the Department of Mathematics at the University of Leicester for their help and support. Finally, I would like to thank my family and friends for their patience and sup- port throughout the past few years. In particular, I thank my wife Lisa and my daughter Ellen, without whom I would have completed this research far quicker, but somehow, it just would not have been the same. At this point I would also like to reassure Lisa that I will get a real job soon. Leicester, Leicestershire, UK Jonathan J. Crofts 31 March 2007 i Contents Abstract iv List of figures v List of tables vi 1 Introduction 1 1.1 History,theoryandapplications . 1 1.2 Periodicorbits............................... 3 1.2.1 Periodicorbittheory . 4 1.2.2 Efficient detection of UPOs . 6 1.3 Extendedsystems............................. 9 1.4 Anoteonnumerics............................ 10 1.4.1 Intervalarithmetic . 12 1.5 Overview.................................. 14 1.6 Thesisresults ............................... 16 2 Conventional techniques for detecting periodic orbits 18 2.1 Specialcases................................ 18 2.1.1 One-dimensionalmaps . -
Transformations)
TRANSFORMACJE (TRANSFORMATIONS) Transformacje (Transformations) is an interdisciplinary refereed, reviewed journal, published since 1992. The journal is devoted to i.a.: civilizational and cultural transformations, information (knowledge) societies, global problematique, sustainable development, political philosophy and values, future studies. The journal's quasi-paradigm is TRANSFORMATION - as a present stage and form of development of technology, society, culture, civilization, values, mindsets etc. Impacts and potentialities of change and transition need new methodological tools, new visions and innovation for theoretical and practical capacity-building. The journal aims to promote inter-, multi- and transdisci- plinary approach, future orientation and strategic and global thinking. Transformacje (Transformations) are internationally available – since 2012 we have a licence agrement with the global database: EBSCO Publishing (Ipswich, MA, USA) We are listed by INDEX COPERNICUS since 2013 I TRANSFORMACJE(TRANSFORMATIONS) 3-4 (78-79) 2013 ISSN 1230-0292 Reviewed journal Published twice a year (double issues) in Polish and English (separate papers) Editorial Staff: Prof. Lech W. ZACHER, Center of Impact Assessment Studies and Forecasting, Kozminski University, Warsaw, Poland ([email protected]) – Editor-in-Chief Prof. Dora MARINOVA, Sustainability Policy Institute, Curtin University, Perth, Australia ([email protected]) – Deputy Editor-in-Chief Prof. Tadeusz MICZKA, Institute of Cultural and Interdisciplinary Studies, University of Silesia, Katowice, Poland ([email protected]) – Deputy Editor-in-Chief Dr Małgorzata SKÓRZEWSKA-AMBERG, School of Law, Kozminski University, Warsaw, Poland ([email protected]) – Coordinator Dr Alina BETLEJ, Institute of Sociology, John Paul II Catholic University of Lublin, Poland Dr Mirosław GEISE, Institute of Political Sciences, Kazimierz Wielki University, Bydgoszcz, Poland (also statistical editor) Prof. -
Chaotic Scattering in Solitary Wave Interactions: a Singular Iterated-Map Description Roy H
CHAOS 18, 023113 ͑2008͒ Chaotic scattering in solitary wave interactions: A singular iterated-map description Roy H. Goodman Department of Mathematical Sciences, New Jersey Institute of Technology, Newark, New Jersey 07102, USA ͑Received 16 October 2007; accepted 7 March 2008; published online 7 May 2008͒ We derive a family of singular iterated maps—closely related to Poincaré maps—that describe chaotic interactions between colliding solitary waves. The chaotic behavior of such solitary-wave collisions depends on the transfer of energy to a secondary mode of oscillation, often an internal mode of the pulse. This map allows us to go beyond previous analyses and to understand the interactions in the case when this mode is excited prior to the first collision. The map is derived using Melnikov integrals and matched asymptotic expansions and generalizes a “multipulse” Melnikov integral. It allows one to find not only multipulse heteroclinic orbits, but exotic periodic orbits. The maps exhibit singular behavior, including regions of infinite winding. These maps are shown to be singular versions of the conservative Ikeda map from laser physics and connections are made with problems from celestial mechanics and fluid mechanics. © 2008 American Institute of Physics. ͓DOI: 10.1063/1.2904823͔ Solitary waves are solutions to time-dependent partial generally lose their distinct identities and merge into a single differential equations (PDEs) which can be described as larger bump. At the opposite extreme are completely inte- profiles of unchanging spatial shape that move at con- grable systems whose solitary waves ͑solitons͒ survive col- stant velocity. A fundamental question is what happens lisions with their identities intact, due to a linear structure when two of them collide. -
Top 300 Semifinalists 2016
TOP 300 SEMIFINALISTS 2016 2016 Broadcom MASTERS Semifinalists 2 About Broadcom MASTERS Broadcom MASTERS® (Math, Applied Science, Technology and Engineering for Rising Stars), a program of Society for Science & the Public, is the premier middle school science and engineering fair competition. Society-affiliated science fairs around the country nominate the top 10% of sixth, seventh and eighth grade projects to enter this prestigious competition. After submitting the online application, the top 300 semifinalists are selected. Semifinalists are honored for their work with a prize package that includes an award ribbon, semifinalist certificate of accomplishment, Broadcom MASTERS backpack, a Broadcom MASTERS decal, a one year family digital subscription to Science News magazine, an Inventor's Notebook and copy of “Howtoons” graphic novel courtesy of The Lemelson Foundation, and a one year subscription to Mathematica+, courtesy of Wolfram Research. In recognition of the role that teachers play in the success of their students, each semifinalist's designated teacher also will receive a Broadcom MASTERS tote bag and a one year subscription to Science News magazine, courtesy of KPMG. From the semifinalist group, 30 finalists are selected and will present their research projects and compete in hands-on team STEM challenges to demonstrate their skills in critical thinking, collaboration, communication and creativity at the Broadcom MASTERS finals. Top awards include a grand prize of $25,000, trips to STEM summer camps and more. Broadcom Foundation and Society for Science & the Public thank the following for their support of 2016 Broadcom MASTERS: • Samueli Foundation • Robert Wood Johnson Foundation • Science News for Students • Wolfram Research • Allergan • Affiliated Regional and State Science • Computer History Museum & Engineering Fairs • Deloitte. -
Projective Synchronization of Chaotic Systems Via Backstepping Design
International Journal of Applied Mathematical Research, 1 (4) (2012) 531-540 ©Science Publishing Corporation www.sciencepubco.com/index.php/IJBAS Projective Synchronization of Chaotic Systems Via Backstepping Design 1 Anindita Tarai (Poria), 2 Mohammad Ali Khan 1 Department of Mathematics, Aligunj R.R.B. High School Midnapore (West), West Bengal, India E-mail: [email protected] 2 Department of Mathematics, Garhbeta Ramsundar Vidyabhavan, Garhbeta, Midnapore (West), West Bengal, India E-mail: [email protected] Abstract Chaos synchronization of discrete dynamical systems are investigated. An algorithm is proposed for projective synchronization of chaotic 2D Duffing map and chaotic Tinkerbell map. The control law was derived from the Lyapunov stability theory. The numerical simulation results are presented to verify the effectiveness of the proposed algorithm Keywords: Lyapunov function, Projective synchronization, Backstepping Design, Duffing map and Tinkerbell map. 1 Introduction Adjacent chaotic trajectories governed by the same nonlinear systems may evolve into a state utterly uncorrelated, but in 1990 Pecora and Carrol [1] shown that it could be synchronized through a proper coupling. Since their seminal paper in 1990, chaos synchronization is an interesting research topic of great attention. Hayes et.al. (1993)[2] have studied to some potential applications in secure communication. Blasius et.al. [3] have observed complex dynamics and phase synchronization in spatially extended ecological systems in 1999 and system identification was investigated by Kocarev et.al. in 1996 [4]. Different forms of synchronization phenomena have been observed in a variety of chaotic systems, such as identical synchronization [1]. In 1996 Rosenblum et.al. [5] have studied phase synchronization of chaotic oscillators. -
Dynamical Systems with Applications Using Mathematicar
DYNAMICAL SYSTEMS WITH APPLICATIONS USING MATHEMATICA⃝R SECOND EDITION Stephen Lynch Springer International Publishing Contents Preface xi 1ATutorialIntroductiontoMathematica 1 1.1 AQuickTourofMathematica. 2 1.2 TutorialOne:TheBasics(OneHour) . 4 1.3 Tutorial Two: Plots and Differential Equations (One Hour) . 7 1.4 The Manipulate Command and Simple Mathematica Programs . 9 1.5 HintsforProgramming........................ 12 1.6 MathematicaExercises. .. .. .. .. .. .. .. .. .. 13 2Differential Equations 17 2.1 Simple Differential Equations and Applications . 18 2.2 Applications to Chemical Kinetics . 27 2.3 Applications to Electric Circuits . 31 2.4 ExistenceandUniquenessTheorem. 37 2.5 MathematicaCommandsinTextFormat . 40 2.6 Exercises ............................... 41 3PlanarSystems 47 3.1 CanonicalForms ........................... 48 3.2 Eigenvectors Defining Stable and Unstable Manifolds . 53 3.3 Phase Portraits of Linear Systems in the Plane . 56 3.4 Linearization and Hartman’s Theorem . 59 3.5 ConstructingPhasePlaneDiagrams . 61 3.6 MathematicaCommands .. .. .. .. .. .. .. .. .. 69 3.7 Exercises ............................... 70 4InteractingSpecies 75 4.1 CompetingSpecies .......................... 76 4.2 Predator-PreyModels . .. .. .. .. .. .. .. .. .. 79 4.3 Other Characteristics Affecting Interacting Species . 84 4.4 MathematicaCommands .. .. .. .. .. .. .. .. .. 86 4.5 Exercises ............................... 87 v vi CONTENTS 5LimitCycles 91 5.1 HistoricalBackground . .. .. .. .. .. .. .. .. .. 92 5.2 Existence and Uniqueness of