# Attribut:Beschreibung DE

Aus International Center for Computational Logic

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Am 11. und 12. Februar fand der 11. Workshop der EMCL-Studenten in Wien statt.
Der Workshop wurde durch die Studenten des Europäischem Master Programm in Computational Logic der Universitäten Bozen, Dresden, Wien und Lissabon selbst organisiert und beinhaltete Vorträge der Studierenden, Alumni, Doktoranten und anderer Wissenschaftler über ihre Forschungsprojekte.
Am Workshop nahmen Studenten aus mehr als 21 Nationen teil.
Dabei wurde der Best Master Thesis Award 2015 an Adrian Rebola Pardo für seine Arbeit über die Generierung von Beweisen in SAT Solvern verliehen.
Abgerundet wurde der Workshop mit einer Tour durch die Stadt zur Domkirche St. Stephan und einem gemeinsamen Abendessen in dem ansässigen Lokal Die Halle.
[http://www.emcl-study.eu www.emcl-study.eu] +

Logics have, for many years, laid claim to providing a formal basis for the study and development of applications and systems in Artificial Intelligence. With the depth and maturity of formalisms, methodologies and logic-based systems today, this claim is stronger than ever.
The European Conference on Logics in Artificial Intelligence (or Journées Européennes sur la Logique en Intelligence Artificielle - JELIA) began back in 1988, as a workshop, in response to the need for a European forum for the discussion of emerging work in this field. Since then, JELIA has been organised biennially, with English as official language, and with proceedings published in Springer-Verlag's Lecture Notes in Artificial Intelligence. Previous meetings took place in Roscoff, France (1988), Amsterdam, Netherlands (1990), Berlin, Germany (1992), York, UK (1994), Évora, Portugal (1996), Dagstuhl, Germany (1998), Málaga, Spain (2000), Cosenza, Italy (2002), Lisbon, Portugal (2004), and Liverpool, UK (2006).
The increasing interest in this forum, its international level with growing participation from researchers outside Europe, and the overall technical quality, has turned JELIA into a major biennial forum for the discussion of logic-based approaches to artificial intelligence. +

Am 20. und 21. Februar findet der 12. Workshop der EMCL-Studenten in Dresden statt.
Der Workshop wird durch die Studenten des Europäischem Master Programm in Computational Logic der Universitäten Bozen, Dresden, Wien und Lissabon selbst organisiert und beinhaltet Vorträge der Studierenden, Alumni, Doktoranten und anderer Wissenschaftler über ihre Forschungsprojekte. Dabei wird der Best Master Thesis Award 2017 verliehen. +

Logische Programmierung ist eine besonders weitgehende Art, Probleme deklarativ zu spezifizieren. In der Form von Prolog geschieht das durch den Einsatz eines Fragments der Logik. Weitergehende Konzepte integrieren in dieses ursprünglich rein relationale Konzept auch Funktionen und Constraints. In den vergangenen Jahren hat dieses Paradigma eine hohe Attraktivität erworben, u.a. in den Bereichen Datenbanken und Verarbeitung von natürlicher Sprache und bei der Modellierung und Bearbeitung komplexer kombinatorischer Probleme. Die Logikprogrammierung ist somit ein aktives Gebiet geblieben, das sich zunehmend auch den schwierigen Thematiken der Integration in die übrige Softwarelandschaft, der Behandlung von Dynamik und des Umgangs mit Kommunikation stellt. +

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The workshops on (constraint) logic programming are the annual meeting of the Society of Logic Programming (GLP e.V.) and bring together researchers interested in logic programming, constraint programming, and related areas like databases and artificial intelligence. Previous workshops have been held in Germany, Austria and Switzerland. The technical program of the workshop will include invited talks, presentations of refereed papers and demo presentations. +

The Workshops on (Constraint) Logic Programming are the annual meeting of the German Society of Logic Programming Gesellschaft für Logische Programmierung e.V. (GLP) and brings together researchers interested in logic programming, constraint programming, answer set programming, and related areas like databases and artificial intelligence (not only from Germany).
The workshops provide a forum for exchanging ideas on declarative logic programming, nonmonotonic reasoning and knowledge representation, and facilitate interactions between research in theoretical foundations and in the design and implementation of logic-based programming systems.
The technical program of the workshop will include invited talks, presentations of refereed papers, and system demonstrations. +

The Workshops on (Constraint) Logic Programming are the annual meeting of the German Society of Logic Programming Gesellschaft für Logische Programmierung e.V. (GLP) and brings together researchers interested in logic programming, constraint programming, answer set programming, and related areas like databases and artificial intelligence (not only from Germany).
The workshops provide a forum for exchanging ideas on declarative logic programming, nonmonotonic reasoning and knowledge representation, and facilitate interactions between research in theoretical foundations and in the design and implementation of logic-based programming systems.
The technical program of the workshop will include invited talks, presentations of refereed papers, and system demonstrations. +

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Im September 2015 findet die jährliche [http://www.tu-dresden.de/inf/ki2015 KI Konferenz] in Dresden inklusive mehrerer Workshops statt. Die Konferenz wird von vielen Mitgliedern des ICCL organisiert. +

KI 2015 is the 38th edition of the German Conference on Artificial Intelligence, which traditionally brings together academic and industrial researchers from all areas of AI, providing a premier forum for exchanging news and research results on theory and applications of intelligent system technology.
In September 2015, prior to the conference, there is an international summer school on reasoning organized by the international center of computational logic. +

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Multi-Agent Systems are communities of problem-solving entities that can perceive and act upon their environment in order to achieve both their individual goals and their joint goals. The work on such systems integrates many technologies and concepts from artificial intelligence and other areas of computing as well as other disciplines. Over recent years, the agent paradigm gained popularity, due to its applicability to a full spectrum of domains, such as search engines, recommendation systems, educational support, e-procurement, simulation and routing, electronic commerce and trade, etc. Computational logic provides a well-defined, general, and rigorous framework for studying the syntax, semantics and procedures for the various tasks in individual agents, as well as the interaction between, and integration amongst, agents in multi-agent systems. It also provides tools, techniques and standards for implementations and environments, for linking specifications to implementations, and for the verification of properties of individual agents, multi-agent systems and their implementations. +

A

Regular path queries (RPQs) are a central component of graph databases. We investigate decision- and enumeration problems concerning the evaluation of RPQs under several semantics that have recently been considered: arbitrary paths, shortest paths, and simple paths.
Whereas arbitrary and shortest paths can be enumerated in polynomial delay, the situation is much more intricate for simple paths. For instance, already the question if a given graph contains a simple path of a certain length has cases with highly non-trivial solutions and cases that are long-standing open problems. We study RPQ evaluation for simple paths from a parameterized complexity perspective and define a class of simple transitive expressions that is prominent in practice and for which we can prove a dichotomy for the evaluation problem. We observe that, even though simple path semantics is intractable for RPQs in general, it is feasible for the vast majority of RPQs that are used in practice. At the heart of our study on simple paths is a result of independent interest: the two disjoint paths problem in directed graphs is W[1]-hard if parameterized by the length of one of the two paths.
'''Bio:''' Wim Martens is a professor for Theoretical Computer Science at the University of Bayreuth. He is interested in theoretical aspects of data management, formal language theory, logic, and complexity. He was an invited speaker at STOC 2017 and his research received several awards, including the ACM SIGMOD research highlight award and the Dissertation Award for Computer Science, Belgium. Currently, he is on the editorial board of ACM TODS and he is chairing the ICDT Council. His talk reports about research for which he recently received the Best Paper Award of the International Conference on Database Theory 2018. +

Abstract:
Bitcoin is currently still the most widely used cryptocurrency, judging from its market cap and trade volume. A big part of Bitcoin's appeal is the mining process, which makes sure that new transactions are being validated and processed in a distributed fashion, maintaining a distributed ledger known as the blockchain. Miners receive a fee for every block of transactions that they mine, as an incentive for their computational effort. In the long run, they can expect a reward proportional to the computational power they provide to the network.
However, Eyal and Sirer introduced a strategy for a miner to time the publishing of blocks that will give them a significant edge in profits.
This talk will present a model for the behaviour of honest and selfish mining pools in UPPAAL, that can be used for analysing properties of the mining process in the presence of network delay, and taking into account the distributed nature of the process. The analysis shows what effects selfish mining would have on the share of profits, but also on the number of orphaned blocks in the blockchain. This analysis also allows us to compares those results to real-world data, to establish if there is evidence for the presence of selfish miners.
Bio:
Ansgar Fehnker is Associate Professor for Programming Education at the Faculty of Electrical Engineeering, Mathematics, and Computer Science, at the University of Twente. He is part of the Formal Methods and Tools group and has been previously professor at the University of the South Pacific and researcher at Australia's ICT research centre NICTA, working on static analysis for C/C++ and on analysis of wireless network protocols with model checking. Prior to joining NICTA he was a PostDoc in the model-checking teams at Carnegie Mellon University, US. He received his PhD from the Radboud University Nijmegen on verification of real-time and hybrid systems. +

<b>Abstract:</b> Existential rules are a knowledge representation and reasoning formalism that extends both positive rules a la Datalog and most description logics used in ontology-based query answering. The chase is a fundamental tool for reasoning on knowledge bases composed of an instance and a set of existential rules. It is well-known that deciding, given a chase variant and a set of existential rules, whether the chase will halt for any instance is an undecidable problem. Hence, a crucial issue is whether it becomes decidable for known classes of existential rules. We focus on three main chase variants, namely semi-oblivious, restricted and core chase, and consider linear existential rules, a simple yet important subclass of existential rules. We show that the termination problem is decidable in these three variants with a novel unified approach based on a single graph and a single notion of forbidden pattern.
Joint work with M. Leclère, M.-L. Mugnier and F. Ulliana.
<b>Speaker Bio:</b> Michaël Thomazo is an INRIA researcher (CEDAR team), currently working on ontology-based query answering, and especially efficient evaluation of reformulated queries. He had been a post-doc at TU Dresden, working with S. Rudolph, and got his Ph.D from the University of Montpellier, supervised by J.-F. Baget and M.-L. Mugnier. You can find more details at http://pages.saclay.inria.fr/michael.thomazo/. +

Column stores have been a 'neglected child' relative to traditional, row-oriented, relation-focused database management systems: The systems people came up with them, and the theoreticians did not really give them the time of day. This talk will discuss what happens when we pick up the slack and formalize a model for analytic computation with columns. In addition to sound conceptual grounding being its own aesthetic reward, we will touch on some of the examples of how such a formalization enables architectural and performance improvements in real-life systems:
Seamless integration of decompression and query execution; removal of special-case handling of different column features (such as nullability and variable-length elements); closure of query execution plans to partial execution; et cetera. Central to achieving such benefits will be the discussion of what constitutes a column, how columns are to be represented, and what they can represent. +

In this talk we will take an introductory glance at the notion of "partition width", first conceived by Achim Blumensath. As partition width is also closely related to a notion of decomposition of an arbitrary structure into a tree-like shape, the so called "partition refinement", we will also take a look at the relation of both these notions to more established notions of decomposition and width measures (namely tree-decompositions, tree width, and clique width). +

A pragmatic approach to translation: Vocabulary alignment through Multiagent Interaction and Observation +

Talk by: Paula Chocrón
Institute: Artificial Intelligence Research Institute (IIIA-CSIC), Barcelona, Spain
Abstract:
"Every speaker that has been abroad knows that understanding a foreign language is easier when performing simple, well-defined interactions. For example, it is easier to ask for a coffee than to discuss politics in a language we do not master. In this talk I will discuss how this idea can be applied to help achieve meaningful communication in artificial multi-agent systems. In open, heterogeneous environments, it is likely that interlocutors with different backgrounds use different languages. Can the contextual information about the tasks being performed be used to learn a translation that allows agents to interact?"
I will start by presenting a notion of context that is based on the formal specifications of the tasks performed by agents. I will then show how this context can be used by agents to align their vocabularies dynamically, by learning mappings from the experience of previous interactions. In doing so, we will also rethink the traditional approach to semantic matching and its evaluation, tackling the following questions: What does it mean for agents to "understand each other"? When is an alignment good for a particular application? Finally, I will present an application to agents that interact using procedural protocols obtained from the WikiHow website, showing how they can infer a translation between English and Spanish without using external resources. +

Many natural combinatorial problems can be expressed as constraint satisfaction problems. This class of problems is known to be NP-complete in general, but certain restrictions on the form of the constraints can ensure tractability. The standard way to parameterize interesting subclasses of the constraint satisfaction problem is via finite constraint languages. The main problem is to classify those subclasses that are solvable in polynomial time and those that are NP-complete. It was conjectured that if a constraint language has a weak near unanimity polymorphism then the corresponding constraint satisfaction problem is tractable, otherwise it is NP-complete. The hardness result is known since 2001. We present an algorithm that solves Constraint Satisfaction Problem in polynomial time for constraint languages having a weak near unanimity polymorphism, which proves the remaining part of the conjecture. +

'''Abstract:'''
When writing today’s distributed programs, which frequently span both devices and cloud services, programmers are faced with complex decisions and coding tasks around coping with failure, especially when these distributed components are stateful. If their application can be cast as pure data processing, they benefit from the past 40-50 years of work from the database community, which has shown how declarative database systems can completely isolate the developer from the possibility of failure in a performant manner. Unfortunately, while there have been some attempts at bringing similar functionality into the more general distributed programming space, a compelling general-purpose system must handle non-determinism, be performant, support a variety of machine types with varying resiliency goals, and be language agnostic, allowing distributed components written in different languages to communicate. This talk describes the first system, publicly available on GitHub, called Ambrosia, to satisfy all these requirements. We coin the term “virtual resiliency”, analogous to virtual memory, for the platform feature which allows failure oblivious code to run in a failure resilient manner. We also introduce a programming construct, the “impulse”, which resiliently handles non-deterministic information originating from outside the resilient component. Of further interest to our community is the effective reapplication of much database performance optimization technology to make Ambrosia more performant than many of today’s non-resilient cloud solutions.
'''Bio:'''
Over the last 20 years, I have worked at Microsoft in a combination of research and product roles. In particular, I’ve spent about 15 years as a researcher at MSR, doing fundamental research in streaming, big data processing, databases, and distributed computing. My style of working is to attack difficult problems, and through fundamental understanding and insight, create new artifacts that enable important problems to be solved in vastly better ways. For instance, my work on streaming data processing enabled people with real time data processing problems to specify their processing logic in new, powerful ways, and also resulted in an artifact called Trill, which was orders of magnitude more performant than anything which preceded it. Within the academic community, I have published many papers, some with best paper awards (e.g. Best Paper Award at ICDE 2012), and two with test of time awards (e.g. SIGMOD 2011 Test of Time award and ICDT 2018 Test of Time award), and have also taken many organizational roles in database conferences. My research has also had significant impact on many Microsoft products, including SQL Server, Office, Windows, Bing, and Halo, as well as leading to the creation of entirely new products like Microsoft StreamInsight, Azure Stream Analytics, Trill, and most recently, Ambrosia. I spent 5 years building Microsoft StreamInsight, serving as a founder and architect for the product. Trill has become the de-facto standard for temporal and stream data processing within Microsoft, and years after creation, is still the most expressive and performant general purpose stream data processor in the world. I am also an inventor of 30+ patents.

Amalgamation SNP (ASNP) is a fragment of existential second-order logic that strictly contains binary connected MMSNP of Feder and Vardi and binary connected guarded monotone SNP of Bienvenu, ten Cate, Lutz, and Wolter; it is a promising candidate for an expressive subclass of NP that exhibits a complexity dichotomy. We show that ASNP has a complexity dichotomy if and only if the infinite-domain dichotomy conjecture holds for constraint satisfaction problems for first-order reducts of binary finitely bounded homogeneous structures. For such CSPs, powerful universal-algebraic hardness conditions are known that are conjectured to describe the border between NP-hard and polynomial-time tractable CSPs. The connection to CSPs also implies that every ASNP sentence can be evaluated in polynomial time on classes of finite structures of bounded treewidth. We show that the syntax of ASNP is decidable. The proof relies on the fact that for classes of finite binary structures given by finitely many forbidden substructures, the amalgamation property is decidable.
This will be a test talk for the presentation of an eponymous paper consisting of the 20 minute long prerecorded talk (like it will be presented at the conference) which will be followed up with a Q&A session to the talk where questions will be answered by Simon Knäuer, one of the authors. Feedback and suggestions in preperation for the conference talk are heavily encouraged.
This talk will be held digitally. If there is any interest in attending, please write an e-mail to thomas.feller@tu-dresden.de. +

ASPARTIX-D is a system designed to evaluate abstract argumentation frameworks. It consists of collection of answer-set programming (ASP) encodings together with an optimal ASP (resp. SAT) solver configuration for each reasoning problem. In this talk we will give an overview of the modifications and the evalutation performed to make ASPARTIX-D
ready for the first International Competition on Computational Models of Argumentation (ICCMA 2015). +