An Introduction to Neural Networks
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An introduction to Neural Networks .. Ben Krose Patrick van der Smagt Eighth edition November c The Universityof Amsterdam Permission is granted to distribute single copies of this book for noncommercial use as long as it is distributed as a whole in its original form and the names of the authors and the University of Amsterdam are mentioned Permission is also granted to use this book for noncommercial courses provided the authors are notied of this b eforehand The authors can b e reached at Ben Krose Patrickvan der Smagt Faculty of Mathematics Computer Science Institute of Rob otics and System Dynamics University of Amsterdam German Aerospace Research Establishment Kruislaan NL SJ Amsterdam POBox D Wessling THE NETHERLANDS GERMANY Phone Phone Fax Fax email krosefwiuvanl email smagtdlrde URL httpwwwfwiuvanlresearchneuro URL httpwwwopdlrdeFFDRRS Contents Preface I FUNDAMENTALS Intro duction Fundamentals A framework for distributed representation Pro cessing units Connections b etween units Activation and output rules Network top ologies Training of articial neural networks Paradigms of learning Mo difying patterns of connectivity Notation and terminology Notation Terminology II THEORY Perceptron and Adaline Networks with threshold activation functions Perceptron learning rule and convergence theorem Example of the Perceptron learning rule Convergence theorem The original Perceptron The adaptive linear element Adaline Networks with linear activation functions the delta rule ExclusiveOR problem Multilayer p erceptrons can do everything Conclusions BackPropagation Multilayer feedforward networks The generalised delta rule Understanding backpropagation Working with backpropagation An example Other activation functions CONTENTS Deciencies of backpropagation Advanced algorithms How go o d are multilayer feedforward networks The eect of the numb er of learning samples The eect of the numb er of hidden units Applications Recurrent Networks The generalised deltarule in recurrentnetworks The Jordan network The Elman network Backpropagation in fully recurrentnetworks The Hopeld network Description Hopeld network as asso ciative memory Neurons with graded resp onse Boltzmann machines SelfOrganising Networks Comp etitive learning Clustering Vector quantisation Kohonen network Principal comp onent networks Intro duction Normalised Hebbian rule Principal comp onent extractor More eigenvectors Adaptive resonance theory Background Adaptive resonance theory ART The simplied neural network mo del ART The original mo del Reinforcement learning The critic The controller network Bartos approach the ASEACE combination Asso ciativesearch Adaptive critic The cartp ole system Reinforcementlearningversus optimal control III APPLICATIONS Rob ot Control Endeector p ositioning Camerarob ot co ordination is function approximation Rob ot arm dynamics Mobile rob ots Mo del based navigation Sensor based control CONTENTS Vision Intro duction Feedforward typ es of networks Selforganising networks for image compression Backpropagation Linear networks Principal comp onents as features The cognitron and neo cognitron Description of the cells Structure of the cognitron Simulation results Relaxation typ es of networks Depth from stereo Image restoration and image segmentation Silicon retina IV IMPLEMENTATIONS General Purp ose Hardware The Connection Machine Architecture Applicability to neural networks Systolic arrays Dedicated NeuroHardware General issues Connectivity constraints Analogue vs digital Optics Learning vs nonlearning Implementation examples Carver Meads silicon retina LEPs LNeuro chip References Index CONTENTS List of Figures The basic comp onents of an articial neural network Various activation functions for a unit Single layer network with one output and two inputs Geometric representation of the discriminant function and the weights Discriminant function b efore and after weight up date The Perceptron The Adaline .