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A Networked Robotic System and Its Use in an Oil Spill Monitoring Exercise
A Networked Robotic System and its Use in an Oil Spill Monitoring Exercise El´oiPereira∗† Co-authors: Pedro Silvay, Clemens Krainerz, Christoph Kirschz, Jos´eMorgadoy, and Raja Sengupta∗ cpcc.berkeley.edu, eloipereira.com [email protected] Swarm at the Edge of the Could - ESWeek'13, Montreal, Canada September 29, 2013 ∗ - Systems Engineering, UC Berkeley y - Research Center, Portuguese Air Force Academy z - Computer Science Dept., University of Salzburg Programming the Ubiquitous World • In networked mobile systems (e.g. teams of robots, smartphones, etc.) the location and connectivity of \machines" may vary during the execution of its \programs" (computation specifications) • We investigate models for bridging \programs" and \machines" with dynamic structure (location and connectivity) • BigActors [PKSBdS13, PPKS13, PS13] are actors [Agh86] hosted by entities of the physical structure denoted as bigraph nodes [Mil09] E. Pereira, C. M. Kirsch, R. Sengupta, and J. B. de Sousa, \Bigactors - A Model for Structure-aware Computation," in ACM/IEEE 4th International Conference on Cyber-Physical Systems, 2013, pp. 199-208. Case study: Oil spill monitoring scenario • \Bilge dumping" is an environmental problem of great relevance for countries with large area of jurisdictional waters • EC created the European Maritime Safety Agency to \...prevent and respond to pollution by ships within the EU" • How to use networked robotics to monitor and take evidences of \bilge dumping" Figure: Portuguese Jurisdiction waters and evidences of \Bilge dumping". -
Annual Report 2019/2020
Annual Report 2019/2020 Contents 6 About VCLA 7 In Memoriam 8 Organization 9 Obituary Edmund M. Clarke 11 Activities 12 LogicLounge 12 LogicLounge: Working as Intended: Surveillance Capitalism is not a Rogue Capitalism 13 Conferences 13 QONFEST 2020 15 CPAIOR 2020 17 Workshops 17 First Vienna Workshop on Computational Social Choice 18 The Helmut-Veith-Memorial Workshop 19 Science Education 19 Project ADA - Algorithms Think Differently 20 Workshop: Introduction to Scratch 21 24h Hackathon: DigiEduHack 2019 22 Hackathon 4 Good Artificial Intelligence 2019 23 Digital Days 2019 24 eEducation Austria Praxistage 2019 25 Hexagonal Debate 2020: How to inspire girls for technology & com puter science? 26 Workshop series: Diary of a computer scientist 28 Distinction 28 VCLA International Student Awards 30 Helmut Veith Stipend Winner 31 Cooperations 31 Workshop Women in Logic 32 Vienna Ball of Sciences 33 Logical Methods in Computer Science 34 Invited Speakers and Visitors 36 Media Coverage 41 VCLA Chairs About VCLA The Vienna Center for Logic and of computer science research, using a Algorithms (VCLA) is a globally unique variety of channels. competence center in the field of logic These objectives are realized through and algorithm research. various activities which include: It was founded in September 2011 and officially opened in January 2012 in the • The VCLA International Student presence of the rector of the Technische Awards for Outstanding Theses Universität Wien (TU Wien) Sabine Se- • The LogicLounge series idler and Turing Award laureate Edmund • The VCLA Workshop Series M. Clarke. The Center was founded by • The VCLA series of winter and Stefan Szeider and Helmut Veith and led summer schools by both until Helmut Veith passed away • The VCLA Visitor Program in March 2016. -
The Space and Motion of Communicating Agents
The space and motion of communicating agents Robin Milner December 1, 2008 ii to my family: Lucy, Barney, Chloe,¨ and in memory of Gabriel iv Contents Prologue vii Part I : Space 1 1 The idea of bigraphs 3 2 Defining bigraphs 15 2.1 Bigraphsandtheirassembly . 15 2.2 Mathematicalframework . 19 2.3 Bigraphicalcategories . 24 3 Algebra for bigraphs 27 3.1 Elementarybigraphsandnormalforms. 27 3.2 Derivedoperations ........................... 31 4 Relative and minimal bounds 37 5 Bigraphical structure 43 5.1 RPOsforbigraphs............................ 43 5.2 IPOsinbigraphs ............................ 48 5.3 AbstractbigraphslackRPOs . 53 6 Sorting 55 6.1 PlacesortingandCCS ......................... 55 6.2 Linksorting,arithmeticnetsandPetrinets . ..... 60 6.3 Theimpactofsorting .......................... 64 Part II : Motion 66 7 Reactions and transitions 67 7.1 Reactivesystems ............................ 68 7.2 Transitionsystems ........................... 71 7.3 Subtransitionsystems .. .... ... .... .... .... .... 76 v vi CONTENTS 7.4 Abstracttransitionsystems . 77 8 Bigraphical reactive systems 81 8.1 DynamicsforaBRS .......................... 82 8.2 DynamicsforaniceBRS.... ... .... .... .... ... .. 87 9 Behaviour in link graphs 93 9.1 Arithmeticnets ............................. 93 9.2 Condition-eventnets .. .... ... .... .... .... ... .. 95 10 Behavioural theory for CCS 103 10.1 SyntaxandreactionsforCCSinbigraphs . 103 10.2 TransitionsforCCSinbigraphs . 107 Part III : Development 113 11 Further topics 115 11.1Tracking................................ -
The Origins of Structural Operational Semantics
The Origins of Structural Operational Semantics Gordon D. Plotkin Laboratory for Foundations of Computer Science, School of Informatics, University of Edinburgh, King’s Buildings, Edinburgh EH9 3JZ, Scotland I am delighted to see my Aarhus notes [59] on SOS, Structural Operational Semantics, published as part of this special issue. The notes already contain some historical remarks, but the reader may be interested to know more of the personal intellectual context in which they arose. I must straightaway admit that at this distance in time I do not claim total accuracy or completeness: what I write should rather be considered as a reconstruction, based on (possibly faulty) memory, papers, old notes and consultations with colleagues. As a postgraduate I learnt the untyped λ-calculus from Rod Burstall. I was further deeply impressed by the work of Peter Landin on the semantics of pro- gramming languages [34–37] which includes his abstract SECD machine. One should also single out John McCarthy’s contributions [45–48], which include his 1962 introduction of abstract syntax, an essential tool, then and since, for all approaches to the semantics of programming languages. The IBM Vienna school [42, 41] were interested in specifying real programming languages, and, in particular, worked on an abstract interpreting machine for PL/I using VDL, their Vienna Definition Language; they were influenced by the ideas of McCarthy, Landin and Elgot [18]. I remember attending a seminar at Edinburgh where the intricacies of their PL/I abstract machine were explained. The states of these machines are tuples of various kinds of complex trees and there is also a stack of environments; the transition rules involve much tree traversal to access syntactical control points, handle jumps, and to manage concurrency. -
Purely Functional Data Structures
Purely Functional Data Structures Chris Okasaki September 1996 CMU-CS-96-177 School of Computer Science Carnegie Mellon University Pittsburgh, PA 15213 Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy. Thesis Committee: Peter Lee, Chair Robert Harper Daniel Sleator Robert Tarjan, Princeton University Copyright c 1996 Chris Okasaki This research was sponsored by the Advanced Research Projects Agency (ARPA) under Contract No. F19628- 95-C-0050. The views and conclusions contained in this document are those of the author and should not be interpreted as representing the official policies, either expressed or implied, of ARPA or the U.S. Government. Keywords: functional programming, data structures, lazy evaluation, amortization For Maria Abstract When a C programmer needs an efficient data structure for a particular prob- lem, he or she can often simply look one up in any of a number of good text- books or handbooks. Unfortunately, programmers in functional languages such as Standard ML or Haskell do not have this luxury. Although some data struc- tures designed for imperative languages such as C can be quite easily adapted to a functional setting, most cannot, usually because they depend in crucial ways on as- signments, which are disallowed, or at least discouraged, in functional languages. To address this imbalance, we describe several techniques for designing functional data structures, and numerous original data structures based on these techniques, including multiple variations of lists, queues, double-ended queues, and heaps, many supporting more exotic features such as random access or efficient catena- tion. In addition, we expose the fundamental role of lazy evaluation in amortized functional data structures. -
Insight, Inspiration and Collaboration
Chapter 1 Insight, inspiration and collaboration C. B. Jones, A. W. Roscoe Abstract Tony Hoare's many contributions to computing science are marked by insight that was grounded in practical programming. Many of his papers have had a profound impact on the evolution of our field; they have moreover provided a source of inspiration to several generations of researchers. We examine the development of his work through a review of the development of some of his most influential pieces of work such as Hoare logic, CSP and Unifying Theories. 1.1 Introduction To many who know Tony Hoare only through his publications, they must often look like polished gems that come from a mind that rarely makes false steps, nor even perhaps has to work at their creation. As so often, this impres- sion is a further compliment to someone who actually adds to very hard work and many discarded attempts the final polish that makes complex ideas rel- atively easy for the reader to comprehend. As indicated on page xi of [HJ89], his ideas typically go through many revisions. The two authors of the current paper each had the honour of Tony Hoare supervising their doctoral studies in Oxford. They know at first hand his kind and generous style and will count it as an achievement if this paper can convey something of the working style of someone big enough to eschew competition and point scoring. Indeed it will be apparent from the following sections how often, having started some new way of thinking or exciting ideas, he happily leaves their exploration and development to others. -
The EATCS Award 2020 Laudatio for Toniann (Toni)Pitassi
The EATCS Award 2020 Laudatio for Toniann (Toni)Pitassi The EATCS Award 2021 is awarded to Toniann (Toni) Pitassi University of Toronto, as the recipient of the 2021 EATCS Award for her fun- damental and wide-ranging contributions to computational complexity, which in- cludes proving long-standing open problems, introducing new fundamental mod- els, developing novel techniques and establishing new connections between dif- ferent areas. Her work is very broad and has relevance in computational learning and optimisation, verification and SAT-solving, circuit complexity and communi- cation complexity, and their applications. The first notable contribution by Toni Pitassi was to develop lifting theorems: a way to transfer lower bounds from the (much simpler) decision tree model for any function f, to a lower bound, the much harder communication complexity model, for a simply related (2-party) function f’. This has completely transformed our state of knowledge regarding two fundamental computational models, query algorithms (decision trees) and communication complexity, as well as their rela- tionship and applicability to other areas of theoretical computer science. These powerful and flexible techniques resolved numerous open problems (e.g., the su- per quadratic gap between probabilistic and quantum communication complex- ity), many of which were central challenges for decades. Toni Pitassi has also had a remarkable impact in proof complexity. She in- troduced the fundamental algebraic Nullstellensatz and Ideal proof systems, and the geometric Stabbing Planes system. She gave the first nontrivial lower bounds on such long-standing problems as weak pigeon-hole principle and models like constant-depth Frege proof systems. She has developed new proof techniques for virtually all proof systems, and new SAT algorithms. -
A Brief Scientific Biography of Robin Milner
A Brief Scientific Biography of Robin Milner Gordon Plotkin, Colin Stirling & Mads Tofte Robin Milner was born in 1934 to John Theodore Milner and Muriel Emily Milner. His father was an infantry officer and at one time commanded the Worcestershire Regiment. During the second world war the family led a nomadic existence in Scotland and Wales while his father was posted to different parts of the British Isles. In 1942 Robin went to Selwyn House, a boarding Preparatory School which is normally based in Broadstairs, Kent but was evacuated to Wales until the end of the war in 1945. In 1947 Robin won a scholarship to Eton College, a public school whose fees were a long way beyond the family’s means; fortunately scholars only paid what they could afford. While there he learned how to stay awake all night solving mathematics problems. (Scholars who specialised in maths were expected to score 100% on the weekly set of problems, which were tough.) In 1952 he won a major scholarship to King’s College, Cambridge, sitting the exam in the Examinations Hall which is 100 yards from his present office. However, before going to Cambridge he did two years’ national military service in the Royal Engineers, gaining a commission as a second lieutenant (which relieved his father, who rightly suspected that Robin might not be cut out to be an army officer). By the time he went to Cambridge in 1954 Robin had forgotten a lot of mathematics; but nevertheless he gained a first-class degree after two years (by omitting Part I of the Tripos). -
Chaining and the Process of Scientific Innovation
Chaining and the process of scientific innovation Emmy Liu ([email protected]) Computer Science and Cognitive Science Programs University of Toronto Yang Xu ([email protected]) Department of Computer Science, Cognitive Science Program University of Toronto Abstract Steyvers, 2004; Prabhakaran, Hamilton, McFarland, & Ju- rafsky, 2016), the evolution of citation frames and net- A scientist’s academic pursuit can follow a winding path. Starting with one topic of research in earlier career, one may works (Jurgens, Kumar, Hoover, McFarland, & Jurafsky, later pursue topics that relate remotely to the initial point. 2018; Zeng, Shen, & Zhou, 2019), and the propagation of Philosophers and cognitive scientists have proposed theories innovation in a specific scientific field (Jurafsky, 2015). about how science has developed, but their emphasis is typi- cally not on explaining the processes of innovation in individ- Our focus here differs from the existing array of work. We ual scientists. We examine regularity in the emerging order of a explore whether there is regularity in a scientist’s innovative scientist’s publications over time. Our basic premise is that sci- research outputs as they emerge over time. Although scien- entific papers should emerge in non-arbitrary ways that tend to follow a process of chaining, whereby novel papers are linked tists vary widely in the subjects they study, we hypothesize to existing papers with closely related ideas. We evaluate this how scientists conceive novel ideas over time should exhibit proposal with a set of probabilistic models on the historical shared tendencies that reflect basic principles of human in- publications from 70 Turing Award winners. -
Computer Laboratory
An introduction to Computer Laboratory Ross Anderson Professor of Security Engineering 1/40 An introduction to Computer Laboratory An academic Department within the University that encompasses Computer Science, along with related aspects of Mathematics, Engineering, and Technology. 1/40 Menu I Some history I Teaching I Research I Entrepreneurship I 2009 Research Students Fund 2/40 Some history 3/40 Mathematical Laboratory (1937-69) In the beginning: one Director. J.E. Lennard-Jones (Prof. Theoretical Chemistry) . and one staff member, M.V. Wilkes (University Demonstrator). 4/40 Mathematical Laboratory (1937-69) In the beginning: Mechanical calculators 4/40 Electronic Delay Storage Automatic Calculator (EDSAC) Maurice Wilkes, May 1949 Practical computer: I 650 instructions/s I 1k x 17 bits I paper tape input I teletype output I 4m x 3m I 3000 valves I 12kW 5/40 Mathematical Laboratory (1937-69) Post-war: One computer to rule them all. EDSAC (’49–’58) EDSAC II (’58–’65) Titan (’64–’73) First ever book on computer programming: Wilkes, Wheeler, and Gill (Addison-Wesley, 1951) 6/40 Professors Wilkes, Wheeler, and Needham in 1992 7/40 Bosses and Buildings 1937 Lennard-Jones 1946 Maurice Wilkes 1970 Computer Laboratory, New Museums Site 1980 Roger Needham 1995 Robin Milner 1999 Ian Leslie 2001 Move to the William Gates Building (Computer Lab and Computing Service get divorced.) 2004 Andy Hopper 8/40 William Gates Building 9/40 Computer Laboratory today Part of the School of Technology and the Faculty of Computer Science & Technology. Staff I 35 -
From Transitions to Executions
From Transitions to Executions? Eleftherios Matsikoudis and Edward A. Lee University of California, Berkeley Abstract. Interleaving theories have traditionally failed to integrate a satisfactory treatment of the so-called “finite delay property". This is generally attributed to the expansion law of such theories, but in truth, the problem is rooted in the concept of labelled transition system. We introduce a new type of system, in which, instead of labelled transitions, we have, essentially, sequences of labelled transitions. We call systems of this type labelled execution systems. We use a coalgebraic representation to obtain, in a canonical way, a suitable concept of bisimilarity among such systems, study the conditions under which that concept agrees with the intuitive understanding of equivalence of branching structure that one has for these systems, and examine their relationship with labelled transition systems, precisely characterizing the difference in expressive power and branching complexity between the two kinds of systems. 1 Introduction The process algebra literature is dominated by the concept of labelled transition system. And to some extent, this is understandable. For process algebra emerged from the marriage of Plotkin's structural operational semantics (see [38]) and Keller's named transition systems (see [27]) (see [34, chap. 12], [9], [39], [7]). This marriage was the work of Robin Milner, and is most clearly expounded in [34], but was already present in [30], where the so-called \expansion law" was stated for the first -
On the Automated Verification of Web Applications with Embedded
On the automated verification of web applications with embedded SQL Shachar Itzhaky1, Tomer Kotek2, Noam Rinetzky3, Mooly Sagiv3, Orr Tamir3, Helmut Veith2, and Florian Zuleger2 1 Massachusetts Institute of Technology 2 Vienna University of Technology 3 Tel Aviv University Abstract A large number of web applications is based on a relational database together with a program, typically a script, that enables the user to interact with the database through embedded SQL queries and commands. In this paper, we introduce a method for formal automated verification of such systems which connects database theory to mainstream program analysis. We identify a fragment of SQL which captures the behavior of the queries in our case studies, is algorithmically decidable, and facilitates the construction of weakest preconditions. Thus, we can integrate the analysis of SQL queries into a program analysis tool chain. To this end, we implement a new decision procedure for the SQL fragment that we introduce. We demonstrate practical applicability of our results with three case studies, a web administrator, a simple firewall, and a conference management system. 1998 ACM Subject Classification D.3.2 Database Management Languages, F.3.1 Specifying and Verifying and Reasoning about Programs Keywords and phrases SQL; Scripting language; Web services; Program verification; Two- variable fragment of First Order logic; Decidability; Reasoning Digital Object Identifier 10.4230/LIPIcs.xxx.yyy.p 1 Introduction Web applications are often written in a scripting language such as PHP and store their data in a relational database which they access using SQL queries and data-manipulating commands [36]. This combination facilitates fast development of web applications, which exploit the reliability and efficiency of the underlying database engine and use the flexibility of the script language to interact with the user.