Bücher der Reihe The Springer International Series in Engineering and Computer Science

arise automatically as a result of the recursive structure of the task and the continuous nature of the SRN's state space. Elman also introduces a new graphical technique for study- ing network behavior based on principal components analysis. He shows that sentences with multiple levels of embedding produce state space trajectories with an intriguing self- similar structure. The development and shape of a recurrent network's state space is the subject of Pollack's paper, the most provocative in this collection. Pollack looks more closely at a connectionist network as a continuous dynamical system. He describes a new type of machine learning phenomenon: induction by phase transition. He then shows that under certain conditions, the state space created by these machines can have a fractal or chaotic structure, with a potentially infinite number of states. This is graphically illustrated using a higher-order recurrent network trained to recognize various regular languages over binary strings. Finally, Pollack suggests that it might be possible to exploit the fractal dynamics of these systems to achieve a generative capacity beyond that of finite-state machines.

Artificial Neural Networks have captured the interest of many researchers in the last five years. As with many young fields, neural network research has been largely empirical in nature, relyingstrongly on simulationstudies ofvarious network models. Empiricism is, of course, essential to any science for it provides a body of observations allowing initial characterization of the field. Eventually, however, any maturing field must begin the process of validating empirically derived conjectures with rigorous mathematical models. It is in this way that science has always pro- ceeded. It is in this way that science provides conclusions that can be used across a variety of applications. This monograph by Michael Lemmon provides just such a theoretical exploration of the role ofcompetition in Artificial Neural Networks. There is "e;good news"e; and "e;bad news"e; associated with theoretical research in neural networks. The bad news isthat such work usually requires the understanding of and bringing together of results from many seemingly disparate disciplines such as neurobiology, cognitive psychology, theory of differential equations, largc scale systems theory, computer science, and electrical engineering. The good news is that for those capable of making this synthesis, the rewards are rich as exemplified in this monograph.

Knowledge Representation and Relation Nets introduces a fresh approach to knowledge representation that can be used to organize study material in a convenient, teachable and learnable form. The method extends and formalizes concept mapping by developing knowledge representation as a structure of concepts and the relationships among them. Such a formal description of analogy results in a controlled method of modeling `new' knowledge in terms of `existing' knowledge in teaching and learning situations, and its applications result in a consistent and well-organized approach to problem solving. Additionally, strategies for the presentation of study material to learners arise naturally in this representation. While the theory of relation nets is dealt with in detail in part of this book, the reader need not master the formal mathematics in order to apply the theory to this method of knowledge representation. To assist the reader, each chapter starts with a brief summary, and the main ideas are illustrated by examples. The reader is also given an intuitive view of the formal notions used in the applications by means of diagrams, informal descriptions, and simple sets of construction rules. Knowledge Representation and Relation Nets is an excellent source for teachers, courseware designers and researchers in knowledge representation, cognitive science, theories of learning, the psychology of education, and structural modeling.

Highly Linear Integrated Wideband Amplifiers: Design and Analysis Techniques for Frequencies from Audio to RF deals with the complicated issues involved in the design of high-linearity integrated wideband amplifiers for different operating frequencies. The book demonstrates these principles using a number of high-performance designs. New topologies for high linearity are presented, as well as a novel method for estimating the intermodulation distortion of a wideband signal. One of the most exciting results presented is an enhanced feedback configuration called feedback boosting that is capable of very low distortion. Also important is a statistical method for relating the intermodulation distortion of a wideband signal to the total harmonic distortion (THD) of a single tone. The THD, as opposed to the intermodulation distortion of the wideband signal, is easy to measure and use as a design parameter. Three different applications where high linearity is needed are identified, namely audio power amplifiers, wideband IF amplifiers and RF power amplifiers. For these applications high-performance integrated amplifier designs using novel topologies are presented together with measurement results. The audio amplifiers are built in CMOS and are capable of driving 8Omega loudspeaker loads directly without using any external components. One of the designs can operate on a supply voltage down to 1.5V. Both bipolar and CMOS wideband IF amplifiers are built; they are fully differential and have linearity from DC to 20 MHz. Finally, an RF power amplifier is built in CMOS, without using inductors, in order to investigate what performance can be achieved without them. Highly Linear Integrated Wideband Amplifiers: Design and Analysis Techniques for Frequencies from Audio to RF is an excellent reference for researchers and designers of integrated amplifiers, and may be used as a text for advanced courses on the topic.

Climate and Environmental Database Systems contains the papers presented at the Second International Workshop on Climate and Environmental Database Systems, held November 21-23, 1995, in Hamburg, Germany. Climate and environmental data may be separated into two classes, large amounts of well structured data and smaller amounts of less structured data. The large amounts are produced by numerical climate models and by satellites, handling data in the order of magnitude of 100 Tbytes for the climate modelling sites and 1000 Tbytes for the recording and processing of satellite data. Smaller amounts of poorly structured data are the environmental data, which come mainly from observations and measurements. Present-day problems in data management are connected with a variety of data types. Climate and Environmental Database Systems addresses the state of the art, practical experience, and future perspectives for climate and environmental database systems, and may be used as a text for a graduate level course on the subject or as a reference for researchers or practitioners in industry.

Discrete Event Systems: Analysis and Control is the proceedings of WODES2000 (the 5th Workshop on Discrete Event Systems, held in Ghent, Belgium, on August 21-23, 2000). This book provides a survey of the current state of the art in the field of modeling, analysis and control synthesis of discrete event systems, lecture notes for a mini course on sensitivity analysis for performance evaluation of timed discrete event systems, and 48 carefully selected papers covering all areas of discrete event theory and the most important applications domains. Topics include automata theory and supervisory control (12); Petri net based models for discrete event systems, and their control synthesis (11); (max,+) and timed automata models (9); applications papers related to scheduling, failure detection, and implementation of supervisory controllers (7); formal description of PLCs (6); and finally, stochastic models of discrete event systems (3).

Enabling Technologies for Computational Science assesses future application computing needs, identifies research directions in problem-solving environments (PSEs), addresses multi-disciplinary environments operating on the Web, proposes methodologies and software architectures for building adaptive and human-centered PSEs, and describes the role of symbolic computing in scientific and engineering PSEs. The book also includes an extensive bibliography of over 400 references. Enabling Technologies for Computational Science illustrates the extremely broad and interdisciplinary nature of the creation and application of PSEs. Authors represent academia, government laboratories and industry, and come from eight distinct disciplines (chemical engineering, computer science, ecology, electrical engineering, mathematics, mechanical engineering, psychology and wood sciences). This breadth and diversity extends into the computer science aspects of PSEs. These papers deal with topics such as artificial intelligence, computer-human interaction, control, data mining, graphics, language design and implementation, networking, numerical analysis, performance evaluation, and symbolic computing. Enabling Technologies for Computational Science provides an assessment of the state of the art and a road map to the future in the area of problem-solving environments for scientific computing. This book is suitable as a reference for scientists from a variety of disciplines interested in using PSEs for their research.

Dependable Network Computing provides insights into various problems facing millions of global users resulting from the `internet revolution'. It covers real-time problems involving software, servers, and large-scale storage systems with adaptive fault-tolerant routing and dynamic reconfiguration techniques. Also included is material on routing protocols, QoS, and dead- and live-lock free related issues. All chapters are written by leading specialists in their respective fields. Dependable Network Computing provides useful information for scientists, researchers, and application developers building networks based on commercially off-the-shelf components.

ATM Network Performance describes a unified approach to ATM network management. The focus is on satisfying quality-of-service requirements for individual B-ISDN connections. For an ATM network of output-buffer switches, the author describes how the basic network resources (switch buffer memory and link transmission bandwidth) should be allocated to achieve the required quality-of-service connections. The performance of proposed bandwidth scheduling policies is evaluated. Both single node and end-to-end performance results are given. In particular, these results are applied to resource provisioning problems for prerecorded (stored) video and video teleconferencing. The flow control problem for available bit rate traffic is also described. This book is intended for a one-term course in performance of Broadband Integrated-Services Digital Networks (B-ISDNs) based on a type of packet-switched communication network called Asynchronous Transfer Mode (ATM). The level of presentation is at the first year of graduate studies and for professionals working in the field, but it may be accessible to senior undergraduates as well. Some familiarity with ATM standards is assumed as such standards are only briefly outlined. All of the required background in discrete-time queueing theory is supplied. Exercises are given at the end of chapters. Solutions and/or hints to selected exercises are given in an Appendix.

Log-domain and translinear filters provide a competitive alternative to the challenges of ever increasing low-voltage, low-power and high frequency demands in the area of continuous-time filters. Since translinear filters are fundamentally large-signal linear, they are capable of realizing a large dynamic range in combination with excellent tunability characteristics. Large-signal linearity is achieved by exploiting the accurate exponential behavior of the bipolar transistor or the subthreshold MOS transistor. A generalization of the dynamic translinear principle exploiting the square law behavior of the MOS transistor is theoretically possible, but not practically relevant. Translinear and log-domain filters are based on the dynamic translinear principle, a generalization of the conventional (static) translinear principle. Besides their application for linear filters, dynamic translinear circuits can also be used for the realization of non-linear dynamic functions, such as oscillators, RMS-DC converters and phase-locked loops. Dynamic Translinear and Log-Domain Circuits: Analysis and Synthesis covers both the analysis and synthesis of translinear circuits. The theory is presented using one unifying framework for both static and dynamic translinear networks, which is based on a current-mode approach. General analysis methods are presented, including the large-signal and non-stationary analysis of noise. A well-structured synthesis method is described greatly enhancing the designability of log-domain and translinear circuits. Comparisons are made with respect to alternative analysis and synthesis methods presented in the literature. The theory is illustrated and verified by various examples and realizations. Dynamic Translinear and Log-Domain Circuits: Analysis and Synthesis is an excellent reference for researchers and circuit designers, and may be used as a text for advanced courses on the topic.

Scheduling in Parallel Computing Systems: Fuzzy and Annealing Techniques advocates the viability of using fuzzy and annealing methods in solving scheduling problems for parallel computing systems. The book proposes new techniques for both static and dynamic scheduling, using emerging paradigms that are inspired by natural phenomena such as fuzzy logic, mean-field annealing, and simulated annealing. Systems that are designed using such techniques are often referred to in the literature as `intelligent' because of their capability to adapt to sudden changes in their environments. Moreover, most of these changes cannot be anticipated in advance or included in the original design of the system. Scheduling in Parallel Computing Systems: Fuzzy and Annealing Techniques provides results that prove such approaches can become viable alternatives to orthodox solutions to the scheduling problem, which are mostly based on heuristics. Although heuristics are robust and reliable when solving certain instances of the scheduling problem, they do not perform well when one needs to obtain solutions to general forms of the scheduling problem. On the other hand, techniques inspired by natural phenomena have been successfully applied for solving a wide range of combinatorial optimization problems (e.g. traveling salesman, graph partitioning). The success of these methods motivated their use in this book to solve scheduling problems that are known to be formidable combinatorial problems. Scheduling in Parallel Computing Systems: Fuzzy and Annealing Techniques is an excellent reference and may be used for advanced courses on the topic.

In knowledge-based natural language generation, issues of formal knowledge representation meet with the linguistic problems of choosing the most appropriate verbalization in a particular situation of utterance. Lexical Semantics and Knowledge Representation in Multilingual Text Generation presents a new approach to systematically linking the realms of lexical semantics and knowledge represented in a description logic. For language generation from such abstract representations, lexicalization is taken as the central step: when choosing words that cover the various parts of the content representation, the principal decisions on conveying the intended meaning are made. A preference mechanism is used to construct the utterance that is best tailored to parameters representing the context. Lexical Semantics and Knowledge Representation in Multilingual Text Generation develops the means for systematically deriving a set of paraphrases from the same underlying representation with the emphasis on events and verb meaning. Furthermore, the same mapping mechanism is used to achieve multilingual generation: English and German output are produced in parallel, on the basis of an adequate division between language-neutral and language-specific (lexical and grammatical) knowledge. Lexical Semantics and Knowledge Representation in Multilingual Text Generation provides detailed insights into designing the representations and organizing the generation process. Readers with a background in artificial intelligence, cognitive science, knowledge representation, linguistics, or natural language processing will find a model of language production that can be adapted to a variety of purposes.

Parallel Numerical Computations with Applications contains selected edited papers presented at the 1998 Frontiers of Parallel Numerical Computations and Applications Workshop, along with invited papers from leading researchers around the world. These papers cover a broad spectrum of topics on parallel numerical computation with applications; such as advanced parallel numerical and computational optimization methods, novel parallel computing techniques, numerical fluid mechanics, and other applications related to material sciences, signal and image processing, semiconductor technology, and electronic circuits and systems design. This state-of-the-art volume will be an up-to-date resource for researchers in the areas of parallel and distributed computing.

Concurrent constraint programming (ccp) is a recent development in programming language design. Its central contribution is the notion of partial information provided by a shared constraint store. This constraint store serves as a communication medium between concurrent threads of control and as a vehicle for their synchronization. Objects for Concurrent Constraint Programming analyzes the possibility of supporting object-oriented programming in ccp. Starting from established approaches, the book covers various object models and discusses their properties. Small Oz, a sublanguage of the ccp language Oz, is used as a model language for this analysis. This book presents a general-purpose object system for Small Oz and describes its implementation and expressivity for concurrent computation. Objects for Concurrent Constraint Programming is written for programming language researchers with an interest in programming language aspects of concurrency, object-oriented programming, or constraint programming. Programming language implementors will benefit from the rigorous treatment of the efficient implementation of Small Oz. Oz programmers will get a first-hand view of the design decisions that lie behind the Oz object system.

Major advances in computing are occurring at an ever-increasing pace. This is especially so in the area of high performance computing (HPC), where today's supercomputer is tomorrow's workstation. High Performance Computing Systems and Applications is a record of HPCS'98, the 12th annual Symposium on High Performance Computing Systems and Applications. The quality of the conference was significantly enhanced by the high proportion of keynote and invited speakers. This book presents the latest research in HPC architecture, networking, applications and tools. Of special note are the sections on computational biology and physics. High Performance Computing Systems and Applications is suitable as a secondary text for a graduate-level course on computer architecture and networking, and as a reference for researchers and practitioners in industry.

Communication protocols are rules whereby meaningful communication can be exchanged between different communicating entities. In general, they are complex and difficult to design and implement. Specifications of communication protocols written in a natural language (e.g. English) can be unclear or ambiguous, and may be subject to different interpretations. As a result, independent implementations of the same protocol may be incompatible. In addition, the complexity of protocols make them very hard to analyze in an informal way. There is, therefore, a need for precise and unambiguous specification using some formal languages. Many protocol implementations used in the field have almost suffered from failures, such as deadlocks. When the conditions in which the protocols work correctly have been changed, there has been no general method available for determining how they will work under the new conditions. It is necessary for protocol designers to have techniques and tools to detect errors in the early phase of design, because the later in the process that a fault is discovered, the greater the cost of rectifying it. Protocol verification is a process of checking whether the interactions of protocol entities, according to the protocol specification, do indeed satisfy certain properties or conditions which may be either general (e.g., absence of deadlock) or specific to the particular protocol system directly derived from the specification. In the 80s, an ISO (International Organization for Standardization) working group began a programme of work to develop formal languages which were suitable for Open Systems Interconnection (OSI). This group called such languages Formal Description Techniques (FDTs). Some of the objectives of ISO in developing FDTs were: enabling unambiguous, clear and precise descriptions of OSI protocol standards to be written, and allowing such specifications to be verified for correctness. There are two FDTs standardized by ISO: LOTOS and Estelle. Communication Protocol Specification and Verification is written to address the two issues discussed above: the needs to specify a protocol using an FDT and to verify its correctness in order to uncover specification errors in the early stage of a protocol development process. The readership primarily consists of advanced undergraduate students, postgraduate students, communication software developers, telecommunication engineers, EDP managers, researchers and software engineers. It is intended as an advanced undergraduate or postgraduate textbook, and a reference for communication protocol professionals.

Interleaving Planning and Execution for Autonomous Robots develops a formal representation for interleaving planning and execution in the context of incomplete information. This work bridges the gap between theory and practice in robotics by presenting control architectures that are provably sound, complete and optimal, and then describing real-world implementations of these robot architectures. Dervish, winner of the 1994 AAAI National Robot Contest, is one of the robots featured. Interleaving Planning and Execution for Autonomous Robots is based on the author's PhD research, covering the same material taught in CS 224, the very popular Introduction to Robot Programming Laboratory taught at Stanford for four years by Professor Michael Genesereth and the author.

Finite Fields are fundamental structures of Discrete Mathematics. They serve as basic data structures in pure disciplines like Finite Geometries and Combinatorics, and also have aroused much interest in applied disciplines like Coding Theory and Cryptography. A look at the topics of the proceed- ings volume of the Third International Conference on Finite Fields and Their Applications (Glasgow, 1995) (see [18]), or at the list of references in I. E. Shparlinski's book [47] (a recent extensive survey on the Theory of Finite Fields with particular emphasis on computational aspects), shows that the area of Finite Fields goes through a tremendous development. The central topic of the present text is the famous Normal Basis Theo- rem, a classical result from field theory, stating that in every finite dimen- sional Galois extension E over F there exists an element w whose conjugates under the Galois group of E over F form an F-basis of E (i. e. , a normal basis of E over F; w is called free in E over F). For finite fields, the Nor- mal Basis Theorem has first been proved by K. Hensel [19] in 1888. Since normal bases in finite fields in the last two decades have been proved to be very useful for doing arithmetic computations, at present, the algorithmic and explicit construction of (particular) such bases has become one of the major research topics in Finite Field Theory.

Multimedia Database Management Systems presents the issues and the techniques used in building multimedia database management systems. Chapter 1 provides an overview of multimedia databases and underlines the new requirements for these applications. Chapter 2 discusses the techniques used for storing and retrieving multimedia objects. Chapter 3 presents the techniques used for generating metadata for various media objects. Chapter 4 examines the mechanisms used for storing the index information needed for accessing different media objects. Chapter 5 analyzes the approaches for modeling media objects, both their temporal and spatial characteristics. Object-oriented approach, with some additional features, has been widely used to model multimedia information. The book discusses two systems that use object-oriented models: OVID (Object Video Information Database) and Jasmine. The models for representing temporal and spatial requirements of media objects are then studied. The book also describes authoring techniques used for specifying temporal and spatial characteristics of multimedia databases. Chapter 6 explains different types of multimedia queries, the methodologies for processing them and the language features for describing them. The features offered by query languages such as SQL/MM (Structured Query Language for Multimedia), PICQUERY+, and Video SQL are also studied. Chapter 7 deals with the communication requirements for multimedia databases. A client accessing multimedia data over computer networks needs to identify a schedule for retrieving various media objects composing the database. The book identifies possible ways for generating a retrieval schedule. Chapter 8 ties together the techniques discussed in the previous chapters by providing a simple architecture of a distributed multimedia database management system. Multimedia Database Management Systems can be used as a text for graduate students and researchers working in the area of multimedia databases. In addition, the book serves as essential reading material for computer professionals who are in (or moving to) the area of multimedia databases.

Symbolic Analysis in Analog Integrated Circuit Design provides an introduction to computer-aided circuit analysis and presents systematic methods for solving linear (i.e. small-signal) and nonlinear circuit problems, which are illustrated by concrete examples. Computer-aided symbolic circuit analysis is useful in analog integrated circuit design. Analytic expressions for the network transfer functions contain information that is not provided by a numerical simulation result. However, these expressions are generally extremely long and difficult to interpret; therefore, it is necessary to be able to approximate them guided by the magnitude of the individual circuit parameters. Engineering has been described as `the art of making approximations'. The inclusion of symbolic analysis in analog circuit design reduces the implied risk of ambiguity during the approximation process. A systematic method based on the nullor concept is used to obtain the basic feedback transistor amplifier configurations. Approximate expressions for the locations of poles and zeros for linear networks are obtained using the extended pole-splitting technique. An unusual feature in Symbolic Analysis in Analog Integrated Circuit Design is the consistent use of the transadmittance element with finite (linear or nonlinear) or infinite (i.e. nullor) gain as the only requisite circuit element. The describing function method is used to obtain approximate symbolic expressions for the harmonic distortion generated by a soft or hard transconductance nonlinearity embedded in an arbitrary linear network. The design and implementation of a program (i.e. CASCA) for symbolic analysis of time-continuous networks is described. The algorithms can also be used to solve other linear problems, e.g. the analysis of time-discrete switched-capacitor networks. Symbolic Analysis in Analog Integrated Circuit Design serves as an excellent resource for students and researchers as well as for industry designers who want to familiarize themselves with circuit analysis. This book may also be used for advanced courses on the subject.

Multimedia Information Retrieval: Content-Based Information Retrieval from Large Text and Audio Databases addresses the future need for sophisticated search techniques that will be required to find relevant information in large digital data repositories, such as digital libraries and other multimedia databases. Because of the dramatically increasing amount of multimedia data available, there is a growing need for new search techniques that provide not only fewer bits, but also the most relevant bits, to those searching for multimedia digital data. This book serves to bridge the gap between classic ranking of text documents and modern information retrieval where composite multimedia documents are searched for relevant information. Multimedia Information Retrieval: Content-Based Information Retrieval from Large Text and Audio Databases begins to pave the way for speech retrieval; only recently has the search for information in speech recordings become feasible. This book provides the necessary introduction to speech recognition while discussing probabilistic retrieval and text retrieval, key topics in classic information retrieval. The book then discusses speech retrieval, which is even more challenging than retrieving text documents because word boundaries are difficult to detect, and recognition errors affect the retrieval effectiveness. This book also addresses the problem of integrating information retrieval and database functions, since there is an increasing need for retrieving information from frequently changing data collections which are organized and managed by a database system. Multimedia Information Retrieval: Content-Based Information Retrieval from Large Text and Audio Databases serves as an excellent reference source and may be used as a text for advanced courses on the topic.

Despite the growing interest in Real-Time Database Systems, there is no single book that acts as a reference to academics, professionals, and practitioners who wish to understand the issues involved in the design and development of RTDBS. Real-Time Database Systems: Issues and Applications fulfills this need. This book presents the spectrum of issues that may arise in various real-time database applications, the available solutions and technologies that may be used to address these issues, and the open problems that need to be tackled in the future. With rapid advances in this area, several concepts have been proposed without a widely accepted consensus on their definitions and implications. To address this need, the first chapter is an introduction to the key RTDBS concepts and definitions, which is followed by a survey of the state of the art in RTDBS research and practice. The remainder of the book consists of four sections: models and paradigms, applications and benchmarks, scheduling and concurrency control, and experimental systems. The chapters in each section are contributed by experts in the respective areas. Real-Time Database Systems: Issues and Applications is primarily intended for practicing engineers and researchers working in the growing area of real-time database systems. For practitioners, the book will provide a much needed bridge for technology transfer and continued education. For researchers, this book will provide a comprehensive reference for well-established results. This book can also be used in a senior or graduate level course on real-time systems, real-time database systems, and database systems or closely related courses.

The subject of this book is Command Control Communication and Information 3 (C I) which is the management infrastructure for any large or complex dynamic resource systems. Here command means the determination of what to do, and control means the ongoing managementofthe execution ofa command. 3 Decision making is the essence of C I which is accomplished through a phased implementation of a set of facilities, communications, personnel, equipment and procedures for monitoring, forecasting, planning, directing, allocating resources, and generating options to achieve specific and general objectives. 3 The C I system that is in question here is for a strategic military command including its subordinate commands. Although the design methodology that will be expounded in the book is for a military system, it can, to a large extent, apply also to tactical military as well as to civilian management information systems (MIS). 3 A C I system is a decision making network that reflects a hierarchical organization 3 of C I nodes. Each node is responsible for the management of some portion ofthe available resources, where the higher level nodes are responsible for a 3 correspondingly greater portion of the resources. Within a C I system both command and control decision making occur at every level of the hierarchy. Command decisions at one level determine how to satisfy the management decisions at a higher level.

Compiler technology is fundamental to computer science since it provides the means to implement many other tools. It is interesting that, in fact, many tools have a compiler framework - they accept input in a particular format, perform some processing and present output in another format. Such tools support the abstraction process and are crucial to productive systems development. The focus of Compiler Technology: Tools, Translators and Language Implementation is to enable quick development of analysis tools. Both lexical scanner and parser generator tools are provided as supplements to this book, since a hands-on approach to experimentation with a toy implementation aids in understanding abstract topics such as parse-trees and parse conflicts. Furthermore, it is through hands-on exercises that one discovers the particular intricacies of language implementation. Compiler Technology: Tools, Translators and Language Implementation is suitable as a textbook for an undergraduate or graduate level course on compiler technology, and as a reference for researchers and practitioners interested in compilers and language implementation.

Real-time systems are defined as those for which correctness depends not only on the logical properties of the produced results, but also on the temporal properties of these results. In a database, real-time means that in addition to typical logical consistency constraints, such as a constraint on a data item's value, there are constraints on when transactions execute and on the `freshness' of the data transactions access. The challenges and tradeoffs faced by the designers of real-time database systems are quite different from those faced by the designers of general-purpose database systems. To achieve the fundamental requirements of timeliness and predictability, not only do conventional methods for scheduling and transaction management have to be redesigned, but also new concepts that have not been considered in conventional database systems or in real-time systems need to be added. Real-Time Database and Information Systems: Research Advances is devoted to new techniques for scheduling of transactions, concurrency management, transaction logging, database languages, and new distributed database architectures. Real-Time Database and Information Systems: Research Advances is primarily intended for practicing engineers and researchers working in the growing area of real-time database and information retrieval systems. For practitioners, the book will provide a much needed bridge for technology transfer and continued education. For researchers, the book will provide a comprehensive reference for well-established results. The book can also be used in a senior or graduate level course on real-time systems, real-time database systems, and database systems, or closely related courses.

In electronic circuit and system design, the word noise is used to refer to any undesired excitation on the system. In other contexts, noise is also used to refer to signals or excitations which exhibit chaotic or random behavior. The source of noise can be either internal or external to the system. For instance, the thermal and shot noise generated within integrated circuit devices are in- ternal noise sources, and the noise picked up from the environment through electromagnetic interference is an external one. Electromagnetic interference can also occur between different components of the same system. In integrated circuits (Ies), signals in one part of the system can propagate to the other parts of the same system through electromagnetic coupling, power supply lines and the Ie substrate. For instance, in a mixed-signal Ie, the switching activity in the digital parts of the circuit can adversely affect the performance of the analog section of the circuit by traveling through the power supply lines and the substrate. Prediction of the effect of these noise sources on the performance of an electronic system is called noise analysis or noise simulation. A methodology for the noise analysis or simulation of an electronic system usually has the following four components: 2 NOISE IN NONLINEAR ELECTRONIC CIRCUITS * Mathematical representations or models for the noise sources. * Mathematical model or representation for the system that is under the in- fluence of the noise sources.

Multi-Threaded Object-Oriented MPI-Based Message Passing Interface: The ARCH Library presents ARCH, a library built as an extension to MPI. ARCH relies on a small set of programming abstractions that allow the writing of well-structured multi-threaded parallel codes according to the object-oriented programming style. ARCH has been written with C++. The book describes the built-in classes, and illustrates their use through several template application cases in several fields of interest: Distributed Algorithms (global completion detection, distributed process serialization), Parallel Combinatorial Optimization (A* procedure), Parallel Image-Processing (segmentation by region growing). It shows how new application-level distributed data types - such as a distributed tree and a distributed graph - can be derived from the built-in classes. A feature of interest to readers is that both the library and the application codes used for illustration purposes are available via the Internet. The material can be downloaded for installation and personal parallel code development on the reader's computer system. ARCH can be run on Unix/Linux as well as Windows NT-based platforms. Current installations include the IBM-SP2, the CRAY-T3E, the Intel Paragon, PC-networks under Linux or Windows NT. Multi-Threaded Object-Oriented MPI-Based Message Passing Interface: The ARCH Library is aimed at scientists who need to implement parallel/distributed algorithms requiring complicated local and/or distributed control structures. It can also benefit parallel/distributed program developers who wish to write codes in the object-oriented style. The author has been using ARCH for several years as a medium to teach parallel and network programming. Teachers can employ the library for the same purpose while students can use it for training. Although ARCH has been used so far in an academic environment, it will be an effective tool for professionals as well. Multi-Threaded Object-Oriented MPI-Based Message Passing Interface: The ARCH Library is suitable as a secondary text for a graduate level course on Data Communications and Networks, Programming Languages, Algorithms and Computational Theory and Distributed Computing and as a reference for researchers and practitioners in industry.

There is broad interest in feature extraction, construction, and selection among practitioners from statistics, pattern recognition, and data mining to machine learning. Data preprocessing is an essential step in the knowledge discovery process for real-world applications. This book compiles contributions from many leading and active researchers in this growing field and paints a picture of the state-of-art techniques that can boost the capabilities of many existing data mining tools. The objective of this collection is to increase the awareness of the data mining community about the research of feature extraction, construction and selection, which are currently conducted mainly in isolation. This book is part of our endeavor to produce a contemporary overview of modern solutions, to create synergy among these seemingly different branches, and to pave the way for developing meta-systems and novel approaches. Even with today's advanced computer technologies, discovering knowledge from data can still be fiendishly hard due to the characteristics of the computer generated data. Feature extraction, construction and selection are a set of techniques that transform and simplify data so as to make data mining tasks easier. Feature construction and selection can be viewed as two sides of the representation problem.

not a coincidence, but is the result of a carefully planned time of landing (sun elevation) and lander orientation (sun azimuth). * The picture was started 25 seconds after touchdown and took 15 seconds to acquire. The alternating bright and dark vertical striations at the left side of the image and the fine particles deposited on the footpad at the right side were caused by a turbulent cloud of dust raised by the lander's retrorockets. t *F. O. Huck and S. D. Wall, "e;Image quality prediction: An aid to the Viking Lander imaging investigation on Mars. "e; Appl. Opt. 15, 1748-1766 (1976). tT. A. Mutch, A. B. Binder, F. O. Huck, E. C. Levinthal, S. Liebes, Jr. , E. C. Morris, W. R. Patterson, J. B. Pollack, C. Sagan and G. R. Taylor, "e;The Surface of Mars: The view from the Viking 1 Lander. "e; Science 193, 791-801 (1976). VISUAL COMMUNICATION An Information Theory Approach Chapter 1 Introduction 1. 1 OBJECTIVE l The fundamental problem of communication, as Shannon stated it, is that of reproducing at one point either exactly or approximately a message selected at another point. In the classical model of communication (Fig. 1. 1), the infor- mation source selects a desired message from a set of possible messages which the transmitter changes into the signal that is actually sent over the commu- nication channel to the receiver. The receiver changes this signal back into a message, and hands this message to the destination.

This book will attempt to give a first synthesis of recent works con- cerning reactive system design. The term "e;reactive system"e; has been introduced in order to at'oid the ambiguities often associated with by the term "e;real-time system,"e; which, although best known and more sugges- tive, has been given so many different meanings that it is almost in- evitably misunderstood. Industrial process control systems, transporta- tion control and supervision systems, signal-processing systems, are ex- amples of the systems we have in mind. Although these systems are more and more computerized, it is sur- prising to notice that the problem of time in computer science has been studied only recently by "e;pure"e; computer scientists. Until the early 1980s, time problems were regarded as the concern of performance evalu- ation, or of some (unjustly scorned) "e;industrial computer engineering,"e; or, at best, of operating systems. A second surprising fact, in contrast, is the growth of research con- cerning timed systems during the last decade. The handling of time has suddenly become a fundamental goal for most models of concurrency. In particular, Robin Alilner 's pioneering works about synchronous process algebras gave rise to a school of thought adopting the following abstract point of view: As soon as one admits that a system can instantaneously react to events, i. e.