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BRICS Newsletter No 9

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BRICS Newsletter No 9 BRICSNewsletter Basic Research in Computer Science No 9, September 1998 In this Issue BRICS. Further details can be obtained by con- tacting the addresses on the back page. Welcome 1 BRICS has had a busy summer, with an excit- Coming Events 2 ing range of activities. They began with the first Which π-Calculus are we Talking About? 2 APPSEM workshop in May, for which Olivier Biological Concepts for Adaptive and Danvy was a chief organiser; it was due to be Distributed Algorithms ......... 2 held at Aarhus under the auspices of BRICS but A Formal Calculus for Distributed Agents 3 because of widespread strikes in Denmark had Mobile Agents in Practise .......... 3 to be moved to G¨oteborg at the last minute. Modelling and Verifying Authentication In June, Peter D. Mosses arranged possibly the Protocols ................. 3 first of a series of short workshops on Appli- Summer School in Semantics ........ 4 cations of Formal Methods, aimed mainly at Reports on Events 4 Danish attendees. The exciting list of invited speakers and satellite meetings helped attract a New Researchers, Guests and PhDs 16 large attendance to ICALP ’98 in Aalborg, organ- Dissertation Abstracts 18 ised by BRICS with Kim Guldstrand Larsen as Reasoning about Reactive Systems .... 18 programme chair and Sven Skyum and Glynn Winskel as vice chairs. Another enjoyable event, New Reports 20 also in July, was the summer school on Cryp- Notes Series 21 tography and Data Security, arranged by Ivan B. Lecture Series 21 Damg˚ard. Lars Arge and Jeffrey S. Vitter held a meeting on Massive Datasets. The workshop News 22 PTAC (Proof Theory and Complexity), organised Folder with BRICS Profile ......... 22 by Carsten Butz, Ulrich Kohlenbach and Søren Robin Milner Honorary Doctorate ..... 22 Riis, capped the end of the summer. It attracted BigWig .................... 23 many big names of the field and gave a fasci- Continuation of AQIP ............ 26 nating and broad view of the state of the art in IFIP WG1.3 .................. 27 Mathematical Logic. CASL ..................... 27 Glynn Winskel is going ahead with plans for a Calendar of Events 28 May summer school on Semantics of Compu- BRICS Address and World Wide Web 28 tation, based around lectures from some of the chapters from the Handbook of Logic and Com- puter Science. Welcome You’ll find a description of these and other recent and future BRICS activities in this newsletter. Welcome to the ninth issue of the BRICS newslet- ter. Its purpose is to inform you of appointments, publications, courses and other activities within 1 Coming Events For details, see the BRICS Activities web page: from evolutionary computing and artificial neu- www.brics.dk/Activities. ral networks, there are surprisingly few stud- ies into potential applications of other biologi- cal ideas that might be useful to IT problems and Which π-Calculus are we Talking questions. About? In this mini-course we will discuss various as- pects of biology, which could be used for novel Late October, 1998, Aarhus. Paola Quaglia, adaptive and distributed algorithms and intro- BRICS, will give a mini-course of 4 double lec- duce some existing biological models already tures on the π-calculus and related calculi. used in in artificial intelligence (AI) and artificial life (ALife). The aim of the course is to raise in- The π-calculus is considered to be the prototypi- terest for these (yet) unused biological ideas and cal calculus for the description of distributed sys- to point at problems related to their identifica- tems with a dynamically changing interconnec- tion and application in computer science. tion topology. It was introduced by R. Milner, J. Parrow, and D. Walker in 1989, and over since it In particular, we will discuss: has proliferated in a family of calculi slightly de- parting from the original one in their view about • Introduction and overview (including gen- interaction. eral introduction and motivation, organi- This will be a self-contained course, meant to be sation and origin of life, and methods for a very basic introduction to π-calculus and π- identification of significant processes) calculi. We will present late and barbed seman- • Emergent properties and self-organisation tics, and touch on polyadicity, asynchrony, and (including concept of emergent properties, their encodings. ALife, chaos theory, and virtual robotics) • Adaptive and distributed information pro- cessing (including concepts and models of Biological Concepts for Adaptive and evolution and genetics) Distributed Algorithms • Means of interaction (including perception, communication, synchronisation, and de- November 9, 10, 11, 16, 17, 1998, Aarhus. Thiemo cision making) Krink, BRICS, will give a mini-course of 5 double • Models for complex interactions in natu- lectures on biological concepts for adaptive and ral and artificial systems (including opti- distributed algorithms. mal foraging theory, game theory, coevolu- Biological ideas can serve as sophisticated mod- tion, and organisation of social systems) els for problem-solving strategies and the de- sign and management of complex computing systems. This potential, found in biological sys- Information about the speaker tems, arises from Nature’s characteristic capabil- ity of parallel processing, self-organisation, effi- Thiemo Krink is currently enrolled as a research ciency and robustness, i.e., effective behaviour assistant professor (Forskningsadjunkt) at the under unpredictably changing conditions. In- BRICS PhD school. He was trained as a com- terestingly, there are various analogies between puter scientist at the Universities of Erlangen- complex systems in computer science and biol- N¨urnberg and Hamburg (Germany), with spe- ogy, as for instance competition for resources, di- cial focus on computer simulation, AI and object- vision of labour or concurrency. However, apart oriented programming. Within these areas he 2 had specific interests in interdisciplinary re- able to an agent at a location. Resources are search, which were stimulated by his medicine themselves equipped with capabilities, and thus studies and his free lance activity as a business an agent may be given permission to send data consultant. As an MSc student, he conducted along a channel at a particular location without two interdisciplinary projects on modelling of being granted permission to read data along the animal behaviour in collaboration with the bi- same channel. ologist prof. Fritz Vollrath at Oxford. In 1994, In the presence of potentially malicious agents he received his MSc degree in computer science we show that the integrity of local resources and continued his research at the Department can still be maintained by incorporating various of Zoology, Aarhus, where he was conferred his forms of type checking into the runtime seman- PhD degree (biology) in 1997. Most of his pa- tics. pers and conference talks were focused on the design and application of virtual robots for bi- ological research. Apart from his own activ- Mobile Agents in Practise ity as a scientific author, his research has been published by public media such as newspapers January, 1999, Aarhus. Vladimiro Sassone, Dept. (e.g., Berlingske Tidende), journals (New Scien- Computer Science, Queen Mary and Westfield tist), books (R. Dawkins: Climbing Mount Im- College, University of London, UK, will give a probable) and TV (e.g. Scientific American Fron- mini-course on Mobile Agents in practise. tiers). His current research interests are in the fields of (i) applications of biological concepts for The lectures will provide an overview of some computational ideas and (ii) theoretical biology of the existing mobile agents programming sys- concerning general models for coevolution and tems, illustrating their designs, features, and behavioural ecology. some implementation issues. We might also fo- cus on few formal calculi to serve as common languages to describe and compare things at an A Formal Calculus for Distributed essential level and, possibly, provide inspiration Agents for future developments. For further information on the lecturer, please re- Late November, 1998, Aarhus. Matthew Hen- fer to his profile on page 16. nessy, School of Cognitive and Computing Sci- ences, University of Sussex, UK, will give a mini-course on a formal calculus for distributed Modelling and Verifying Authentica- agents. tion Protocols The lectures will examine a formal language for describing widely distributed open systems January–February, 1999, Aarhus. Sanjiva Prasad, where mobile agents can move from site to site IIT (Indian Institute of Technology), Delhi, India, seeking resources and effecting computations. will give a mini-course on modelling and verify- We will principally be concerned with type sys- ing authentication protocols. tems for such agents which guarantee no misuse With the growth of the internet, and commu- of local resources, even in the presence of agents nication between distributed sites, security and which may harbour malicious intentions. privacy are “hot” topics. A class of protocols, The language, Dpi, is obtained by adding to the called authentication protocols, are used to es- the π-calculus new constructs for located pro- tablish (with cryptography) secure communica- cesses and process migration. The type system tion channels between distributed agents. We is based on the notion of a location type, which will study some approaches to specifying and describes the set of resources (channels) avail- modelling such protocols, and to establish their 3 correctness, assuming perfect cryptography. The As part of this programme Glynn Winskel is or- focus of our treatment will be on process calculus ganising a Summer School on Semantics, based approaches and general theorem-proving tech- principally on part 3 of the Handbook. The Sum- niques, as opposed to belief logics and logic pro- mer School will take place here in Aarhus over a gramming approaches. A working knowledge week in May 1999 (the precise time is to be fixed of the π-calculus will be assumed. shortly). For further information on the lecturer, please re- So far the following lectures are planned: fer to his profile on page 16.
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