ICALP { the International Colloquium on Automata, Languages, and Progr- ming { is a series of annual conferences of the European Association for Th- retical Computer Science (EATCS). ICALP'99 was organized by the Institute of Computer Science of the Academy of Sciences of the Czech Republic in - operation with the Action M Agency. Stimulated by the positive experience from previous meetings, the guiding idea of the ICALP'99 organization was to keep and to enhance the idea of a parallel two{track conference with invited plenary talks. Similarly to the two parts of the journal Theoretical Computer Science, Track A of the meeting is devoted to Algorithms, Automata, Complexity, and Games, and Track B to Logic, Semantics, and Theory of Programming. The Program Committee was structured along these same lines. As a further inno- tion, ICALP'99 was coordinated with the European Symposium on Algorithms (ESA'99) in such a way that both conferences took place in the same location with the former immediately followed by the latter. ICALP'99 was the 26th in the series of ICALP colloquia. Previous colloquia were held in Paris (1972), Saarbruc ] ken (1974), Edinburgh (1976), Turku (1977), Udine (1978), Graz (1979), Amsterdam (1980), Haifa (1981), Aarhus (1982), Barcelona (1983), Antwerp (1984), Nafplion (1985), Rennes (1986), Karlsruhe (1987), Tampere (1988), Stresa (1989), Warwick (1990), Madrid (1991), Vienna (1992), Lund (1993), Jerusalem (1994), Szeged (1995), Paderborn (1996), Bo- gna (1997), and Aalborg (1998). In the year 2000 ICALP will be held in Geneva."

This book constitutes the proceedings of the Second International Workshop on Mobile Agents, MA'98, held in Stuttgart, Germany, in September 1998.
The 21 revised full papers presented were carefully selected from a total of 45 submissions; also included are three invited contributions. The book is divided in topical sections on mechanisms for mobile agent systems, mobile agent architechtures, applications, mobile agent systems, security, and communication.

Although machine interfaces have been made much easier for novices to learn, still very little is known about how users progress from novice to expert performance. This volume is based upon the results of one of the largest continuous field studies ever performed in human-computer interactiona seven year study involving 4,000 students at Sydney University. The results will be valuable to software developers and researchers.

ETAPS 99 is the second instance of the EuropeanJoint Conferences on T- ory and Practice of Software. ETAPS is an annual federated conference that was established in 1998 by combining a number of existing and new conferences. This year it comprises ?ve conferences (FOSSACS, FASE, ESOP, CC, TACAS), four satellite workshops (CMCS, AS, WAGA, CoFI), seven invited lectures, two invited tutorials, and six contributed tutorials. The events that comprise ETAPS address various aspects of the system - velopment process, including speci?cation, design, implementation, analysis and improvement. The languages, methodologies and tools which support these - tivities are all well within its scope. Di?erent blends of theory and practice are represented, with an inclination towards theory with a practical motivation on one hand and soundly-based practice on the other. Many of the issues involved in software design apply to systems in general, including hardware systems, and the emphasis on software is not intended to be exclusive."

Correct Systems looks at the whole process of building a business process model, capturing that in a formal requirements statement and developing a precise specification. The issue of testing is considered throughout the process and design for test issues are fundamental to the approach. A model (language) and a methodology are presented that is very powerful, very easy to use and applicable for the "new world" of component based systems and the integration of systems from dependable components. This book discusses a new area which will be of interest to both software and hardware designers. It presents specification, design, implementation and testing in a user-oriented fashion using simple formal and diagramming techniques with a high level of user-friendliness. The first part provides a simple introduction to the method together with a complete, real case study. The second part describes, in detail, the mathematical theory behind the methods and the claims made.

This book gathers together research from three key application themes of modelling in operational research - modelling to support evaluation and change in organisations; modelling within the development and use of organisational information systems; and the use of modelling approaches to support, enable and enhance decision support in organisational contexts. The issues raised provide valuable insight into the range of ways in which operational research techniques and practices are being successfully applied in today's information-centred business world. Modelling for Added Value provides a window onto current research and practise in modelling techniques and highlights their rising importance across the business, industrial and commercial sectors. The book contains contributions from a mix of academics and practitioners and covers a range of complex and diverse modelling issues, highlighting the broad appeal of this increasingly important subject area.

User modeling researchers look for ways of enabling interactive software systems to adapt to their users-by constructing, maintaining, and exploiting user models, which are representations of properties of individual users. User modeling has been found to enhance the effectiveness and/or usability of software systems in a wide variety of situations. Techniques for user modeling have been developed and evaluated by researchers in a number of fields, including artificial intelligence, education, psychology, linguistics, human-computer interaction, and information science. The biennial series of International Conferences on User Modeling provides a forum in which academic and industrial researchers from all of these fields can exchange their complementary insights on user modeling issues. The published proceedings of these conferences represent a major source of information about developments in this area.

This book presents the thoroughly refereed post-workshop proceedings of the 9th International Workshop on Languages and Compilers for Parallel Computing, LCPC'96, held in San Jose, California, in August 1996.
The book contains 35 carefully revised full papers together with nine poster presentations. The papers are organized in topical sections on automatic data distribution and locality enhancement, program analysis, compiler algorithms for fine-grain parallelism, instruction scheduling and register allocation, parallelizing compilers, communication optimization, compiling HPF, and run-time control of parallelism.

Dependability has always been an vital attribute of operational systems, regardless of whether they are highly-specialised (like electricity generating plants) or more general-purpose (like domestic appliances). This volume provides a highly-readable overview of the topic, concentrating on dependability as a life-cycle management issue rather than as a technical subject. Specifically avoiding technical language and complex mathematics, it is designed to be accessible to readers at all levels. It will be of particular interest to project managers and software engineers in industries where dependability is of particular importance, such as aerospace, process control, and mining. It will also provide useful reading material for students taking courses with modules in dependability. Felix Redmill and Chris Dale have both worked in industry for over 15 years, and now run successful consultancy businesses.

This book presents the refereed proceedings of the First International Conference on Mobile Agents, MA '97, held in Berlin, Germany, in April 1997.
Mobile Agents offer unique opportunities for structuring and implementing distributed systems. A wide range of applications has been identified for mobile agent technology, including electronic commerce, telecommunication services, network management, group work, and workflow management.
The 18 revised full papers presented in the volume were selected out of a total of 34 submissions; all in all they reflect the state of the art in the exciting area of mobile agent technology.

This book constitutes the refereed proceedings of the First International Workshop on Communication and Architectural Support for Network-Based Parallel Computing, CANPC'97, held in San Antonio, Texas, USA, in February 1997.
The 19 revised full papers presented were carefully selected from a total of 36 submissions. Among the topics addressed are processor/network interfaces, communication protocols, high-performance network technology, operating systems and architectural issues, and load balancing techniques. All in all, the papers competently describe the state-of-the-art for network-based computing systems.

This book constitutes the refereed proceedings of the Second International Conference on Worldwide Computing and Its Applications, WWCA'98, held in Tsukuba, Japan, in March 1998.
This volume presents 14 invited and survey papers together with 20 papers selected by the conference committee. The volume is divided into topical sections on distributed objects, distributed componentware, distributed systems platforms, Internet technology, mobile computing, interculture technology, collaborative media, collaborative support, information discovery and retrieval, novel network applications.

This book constitutes the refereed proceedings of the Third International Conference of the Austrian Center for Parallel Computation, ACPC '96, held in Klagenfurt, Austria, in September 1996.
The 15 revised full papers presented together with two keynote contributions were selected from 31 submissions by authors from 13 countries. Also included are two industrial papers and six posters. The topical emphasis of the book is on parallel databases and parallel input/output aspects; however also other topics are addressed, like parallel hardware, parallel numerics, parallel languages, and tools and algorithms.

The Juniper Networks routing platforms are becoming the go-to solution for core, edge, metro and remote office networks, and JUNOS software is behind it all. The operating system is so full of industrial-strength routing protocols and IP innovations that those treading into the world of JUNOS will need clarification, explanation, and a showcase example or two. Look no further. This "JUNOS Cookbook" provides it all and more.

Yes, you can mine through the 5,000 pages of documentation or take a two-thousand-dollar training course, but JUNOS's interprocess sophistication can be baffling unless you know the shortcuts and tricks, as well as those rays of illuminating comprehension that can come only from those who live with it. "JUNOS Cookbook" is the first comprehensive book about JUNOS software and it provides over 200 time-saving step-by-step techniques including discussions about the processes and alternative ways to perform the same task. It's been tested and tech-reviewed by field engineers who know how to take JUNOS out for a spin and it's applicable to the entire line of M-, T-, and J-series routers." JUNOS Cookbook" will not only pay for itself the first few times you use it, it will make your network easier to manage and update.

"Aviva Garrett has done a tremendous job of distilling the features of JUNOS software in a form that will be useful for a wide audience-students, field engineers, network architects, and other networking professionals alike will benefit from this book. For many people, this is the only book on JUNOS they will need." Pradeep Sindhu, CTO and Founder, Juniper Networks

"This cookbook is superb. Aviva Garrett has masterfully assembled a complete setof practical real-world examples with step-by-step instructions. Security, management, routing: it's all here!" Stephen Gill, Research Fellow, Team Cymru

"A technical time-saver for any NOC or SOC working with JUNOS. It's clear, concise, and informative recipes are are an invaluable resource." Scott A. McIntyre, Security Officer, XS4ALL Internet B.V

This book presents the refereed proceedings of the International Workshop on Parallel Symbolic Languages and Systems, PSLS '95, held in Beaune, France, in October 1995.
The 21 full papers included in the book were carefully selected for presentation at the meeting and thoroughly revised afterwards. Parallel symbolic computing has gained in importance for high-performance computing; in recent years, many applications have been implemented using C, C++, and their parallel extensions. This volume is organized in sections on evaluation strategies, programming tools, irregular data structures and applications, systems, and distributed models and systems.

This book presents the refereed proceedings of the Sixth International Conference on Compiler Construction, CC '96, held in Link ping, Sweden in April 1996.
The 23 revised full papers included were selected from a total of 57 submissions; also included is an invited paper by William Waite entitled "Compiler Construction: Craftsmanship or Engineering?." The book reports the state of the art in the area of theoretical foundations and design of compilers; among the topics addressed are program transformation, software pipelining, compiler optimization, program analysis, program inference, partial evaluation, implementational aspects, and object-oriented compilers.

This book presents the refereed proceedings of the Second International Workshop on Tools and Algorithms for the Construction and Analysis of Systems, TACAS '96, held in Passau, Germany in March 1996.
The book presents 19 revised full papers selected from a total of 47 submissions together with 11 tool presentations and 3 invited papers. The collection of papers addresses all current aspects of the design and analysis of distributed systems; the volume is organized in topical sections on tools, model checking and testing, security, models and methods, case studies, and logic and programs.

This book constitutes the strictly refereed post-conference proceedings of the International Conference on Worldwide Computing and Its Applications, WWCA'97, held in Tsukuba, Japan, in March 1997.
The volume presents 15 revised full papers selected from 50 submissions as well as 15 revised invited papers by leading researchers in this emerging area and two keynotes. The papers are organized in topical sections on distributed programming languages and systems, distributed object environments, cooperative computation, collaboration support Systems, collaborative media, novel distributed applications, Internet and protocols, distributed system platforms, mobile computing, and application gateways.

This book presents the refereed proceedings of the Eighth Annual Workshop on Languages and Compilers for Parallel Computing, held in Columbus, Ohio in August 1995.
The 38 full revised papers presented were carefully selected for inclusion in the proceedings and reflect the state of the art of research and advanced applications in parallel languages, restructuring compilers, and runtime systems. The papers are organized in sections on fine-grain parallelism, interprocedural analysis, program analysis, Fortran 90 and HPF, loop parallelization for HPF compilers, tools and libraries, loop-level optimization, automatic data distribution, compiler models, irregular computation, object-oriented and functional parallelism.

This book presents 12 revised refereed papers selected as the best from 32 submissions for the First International Workshop on Tools and Algorithms for the Construction and Analysis of Systems, TACAS '95, held in Aarhus, Denmark, in May 1995.
The workshop brought together 46 researchers interested in the development and application of tools and algorithms for specification, verification, analysis, and construction of distributed systems. The papers included in the book are devoted to refinement-based and compositional verification, construction techniques, analysis and verification via theorem proving, process algebras, temporal and modal logics, techniques for real-time, hybrid and probabilistic systems, and value-passing systems.

This book is the proceedings of the Structures in Concurrency Theory workshop (STRICT) that was held from 11 th to l3th May 1995 in Berlin, Germany. It includes three invited contributions - by J. de Bakker, E. Best et aI, and E. R. Olderog and M. Schenke - and all papers which were submitted and accepted for presentation. Concurrency Theory deals with formal aspects of concurrent systems. It uses partly competing and partly complementary formalisms and structures. The aim of this workshop was to present and compare different formalisms and results in Concurrency Theory. STRICT was organized by the Humboldt-University Berlin and the ESPRIT Basic Research Working Group CALIBAN. Original papers had been sought from all scientists in the field of Concurrency Theory. The Programme Committee selected twenty contributions with various different topics, including Petri Nets, Process Algebras, Distributed Algorithms, Formal Semantics, and others. I am grateful to the Programme Committee and to the other referees for the careful evaluation of the submitted papers.

This book constitutes the refereed revised post-workshop proceedings of the 5th International Workshop on Network and Operating Systems Support for Digital Audio and Video, NOSSDAV '95, held in Durham, New Hampshire, USA in April 1995.
The 24 full papers included were selected from a total of 101 submissions; together with overviews by the session chairpersons they reflect the state of the art in networking and operating systems support for multimedia. The papers are organized in sections on advance reservation systems, operating systems support, resource management and quality of service, audio and video systems, and scheduling and synchronization.

This book constitutes the proceedings of the 8th International Conference on Modelling Techniques and Tools for Computer Performance Evaluation (Performance Tools '95) and of the 8th GI/ITG Conference on Measuring, Modelling and Evaluating Computing and Communication Systems, MMB '95, held jointly in Heidelberg, Germany in September 1995.
The volume presents 26 full refereed papers selected from a total of 86 submissions, together with two invited contributions. The scope of the papers includes measurement- and model-based approaches for quantitative systems assessment, reports on theoretical and methodological progress, and novel and improved assessment techniques and their tool implementations and applications.

Following five successful workshops in the previous five years, the Rendering Workshop is now well established as a major international forum and one of the most reputable events in the field of realistic image synthesis. Including the best 31 papers which were carefully evaluated out of 68 submissions the book gives an overview on hierarchical radiosity, Monte Carlo radiosity, wavelet radiosity, nondiffuse radiosity, and radiosity performance improvements. Some papers deal with ray tracing, reconstruction techniques, volume rendering, illumination, user interface aspects, and importance sampling. Also included are two invited papers by James Arvo and Alain Fournier. As is the style of the Rendering Workshop, the contributions are mainly of algorithmic nature, often demonstrated by prototype implementations. From these implementations result numerous color images which are included as appendix. The Rendering Workshop proceedings are certainly an obligatory piece of literature for all scientists working in the rendering field, but they are also very valuable for the practitioner involved in the implementation of state of the art rendering system certainly influencing the scientific progress in this field.

27 contributions treat the state of the art in Monte Carlo and Finite Element methods for radiosity and radiance. Further special topics dealt with are the use of image maps to capture light throughout space, complexity, volumetric stochastic descriptions, innovative approaches to sampling and approximation, and system architecture. The Rendering Workshop proceedings are an obligatory piece of literature for all scientists working in the rendering field, but they are also very valuable for the practitioner involved in the implementation of state of the art rendering system certainly influencing the scientific progress in this field.