Hide menu

AIICS Publications: Other Publications

Hide abstracts BibTeX entries
[43] Full text  Oleg Burdakov, Patrick Doherty and Jonas Kvarnström. 2014.
Optimal Scheduling for Replacing Perimeter Guarding Unmanned Aerial Vehicles.
Technical Report. In series: LiTH-MAT-R #2014:09. Linköping University Electronic Press. 16 pages.

Guarding the perimeter of an area in order to detect potential intruders is an important task in a variety of security-related applications. This task can in many circumstances be performed by a set of camera-equipped unmanned aerial vehicles (UAVs). Such UAVs will occasionally require refueling or recharging, in which case they must temporarily be replaced by other UAVs in order to maintain complete surveillance of the perimeter. In this paper we consider the problem of scheduling such replacements. We present optimal replacement strategies and justify their optimality.

[42] Full text  Oleg Burdakov, Patrick Doherty and Jonas Kvarnström. 2014.
Local Search for Hop-constrained Directed Steiner Tree Problem with Application to UAV-based Multi-target Surveillance.
Technical Report. In series: LiTH-MAT-R #2014:10. Linköping University Electronic Press. 25 pages.

We consider the directed Steiner tree problem (DSTP) with a constraint on the total number of arcs (hops) in the tree. This problem is known to be NP-hard, and therefore, only heuristics can be applied in the case of its large-scale instances. For the hop-constrained DSTP, we propose local search strategies aimed at improving any heuristically produced initial Steiner tree. They are based on solving a sequence of hop-constrained shortest path problems for which we have recently developed ecient label correcting algorithms. The presented approach is applied to nding suitable 3D locations where unmanned aerial vehicles (UAVs) can be placed to relay information gathered in multi-target monitoring and surveillance. The eciency of our algorithms is illustrated by results of numerical experiments involving problem instances with up to 40 000 nodes and up to 20 million arcs.

[41] Luc De Raedt, Christian Bessiere, Didier Dubois, Patrick Doherty, Paolo Frasconi, Fredrik Heintz and Peter Lucas. 2012.
Proceedings of the 20th European Conference on Artificial Intelligence (ECAI).
Conference Proceedings. In series: Frontiers in Artificial Intelligence and Applications #242. IOS Press. 1056 pages. ISBN: 978-1-61499-097-0.

[40] Bernhard Nebel and Alexander Kleiner. 2012.
Multi-Agenten-Systeme in der Intralogistik - Erster Teil: Gemeinsam denken.
IEE - Elektrische Automatisierung + Antriebstechnik, -(4):48–53. Hüthig Verlag.
Link to journal: http://www.iee-online.de/2012/

Nicht nur in der Logistik und in der Produktion setzt es sich immer mehr durch, die Steuerung und Überwachung von Aufgaben zu verteilen. Für eine solche Vorgehens- weise sind sogenannte Multi-Agenten-Systeme (MAS) geeignet, bei denen mehrere ei- genständige Systeme miteinander kommunizieren, sich koordinieren und kooperieren. Eine spezielle Form solcher MAS sind Multi-Roboter-Systeme.

[39] Bernhard Nebel and Alexander Kleiner. 2012.
Multi-Agenten-Systeme in der Intralogistik - Zweiter Teil: Effizient transportieren.
IEE - Elektrische Automatisierung + Antriebstechnik, -(5):34–37. Hüthig Verlag.
Link to journal: http://www.iee-online.de/2012/

In der Logisitk, in der Produktion und und in anderen Bereichen setzt es sich immer mehr durch, zentrale Instanzen zu vermeiden und die Steuerung und Überwachung von Aufgaben zu verteilen. Für eine solche Vorgehensweise sind so genannte Multi-Agenten-Systeme (MAS) ideal geeignet, bei denen mehrere eigenständige Systeme miteinander kommunizieren, sich koordinieren und kooperieren. Eine spezielle Form solcher MAS sind Multi-Roboter-Systeme, bei denen die einzelnen Agenten sich selbständig bewegende physikalische Einheiten sind, wie z.B. bei einer Gruppe von Reinigungsrobotern, einem Roboterfußballteam oder im Logistiksystem KARIS.

[38] Full text  Erik Sandewall. 2012.
Maintaining Live Discussion in Two-Stage Open Peer Review.
Frontiers in Computational Neuroscience, 6(9):????. Frontiers Research Foundation.
DOI: 10.3389/fncom.2012.00009.
Note: funding agencies|Knut and Alice Wallenberg Foundation||
fulltext:print: http://liu.diva-portal.org/smash/get/div...

Open peer review has been proposed for a number of reasons, in particular, for increasing the transparency of the article selection process for a journal, and for obtaining a broader basis for feedback to the authors and for the acceptance decision. The review discussion may also in itself have a value for the research community. These goals rely on the existence of a lively review discussion, but several experiments with open-process peer review in recent years have encountered the problem of faltering review discussions. The present article addresses the question of how lively review discussion may be fostered by relating the experience of the journal Electronic Transactions on Artificial Intelligence (ETAI) which was an early experiment with open peer review. Factors influencing the discussion activity are identified. It is observed that it is more difficult to obtain lively discussion when the number of contributed articles increases, which implies difficulties for scaling up the open peer review model. Suggestions are made for how this difficulty may be overcome.

[37] Anders Kofod-Peteresen, Fredrik Heintz and Langseth Helge. 2011.
Elevent Scandinavian Conference on Artifical Intelligence SCAI 2011.
Conference Proceedings. In series: Frontiers in Artificial Intelligence and Applications #227. IOS Press. 197 pages. ISBN: 978-1-60750-753-6.

[36] Anna Pernestål, Mattias Nyberg and Håkan Warnquist. 2009.
Modeling and Efficient Inference for Troubleshooting Automotive Systems.
Technical Report. In series: LiTH-ISY-R #2921. Linköpings universitet.

We consider computer assisted troubleshooting of automotive vehicles, where the objective is to repair the vehicle at as low expected cost as possible.The work has three main contributions: a troubleshooting method that applies to troubleshooting in real environments, the discussion on practical issues in modeling for troubleshooting, and the efficient probability computations.The work is based on a case study of an auxiliary braking system of a modern truck.We apply a decision theoretic approach, consisting of a planner and a diagnoser.Two main challenges in troubleshooting automotive vehicles are the need for disassembling the vehicle during troubleshooting to access parts to repair, and the difficulty to verify that the vehicle is fault free. These facts lead to that probabilities for faults and for future observations must be computed for a system that has been subject to external interventions that cause changes the dependency structure. The probability computations are further complicated due to the mixture of instantaneous and non-instantaneous dependencies.To compute the probabilities, we develop a method based on an algorithm, <em>updateBN</em>, that updates a static BN to account for the external interventions.

[35] Oleg Burdakov, Kaj Holmberg, Patrick Doherty and Per-Magnus Olsson. 2009.
Optimal placement of communications relay nodes.
Technical Report. In series: LiTH-MAT-R #2009:3. Linköpings universitet. 21 pages.

We consider a constrained optimization problem with mixed integer and real variables. It models optimal placement of communications relay nodes in the presence of obstacles. This problem is widely encountered, for instance, in robotics, where it is required to survey some target located in one point and convey the gathered information back to a base station located in another point. One or more unmanned aerial or ground vehicles (UAVs or UGVs) can be used for this purpose as communications relays. The decision variables are the number of unmanned vehicles (UVs) and the UV positions. The objective function is assumed to access the placement quality. We suggest one instance of such a function which is more suitable for accessing UAV placement. The constraints are determined by, firstly, a free line of sight requirement for every consecutive pair in the chain and, secondly, a limited communication range. Because of these requirements, our constrained optimization problem is a difficult multi-extremal problem for any fixed number of UVs. Moreover, the feasible set of real variables is typically disjoint. We present an approach that allows us to efficiently find a practically acceptable approximation to a global minimum in the problem of optimal placement of communications relay nodes. It is based on a spatial discretization with a subsequent reduction to a shortest path problem. The case of a restricted number of available UVs is also considered here. We introduce two label correcting algorithms which are able to take advantage of using some peculiarities of the resulting restricted shortest path problem. The algorithms produce a Pareto solution to the two-objective problem of minimizing the path cost and the number of hops. We justify their correctness. The presented results of numerical 3D experiments show that our algorithms are superior to the conventional Bellman-Ford algorithm tailored to solving this problem.

[34] Fredrik Heintz and Jonas Kvarnström. 2009.
Proceedings of the Swedish AI Society Workshop 2009.
Conference Proceedings. In series: Linköping Electronic Conference Proceedings #35. Linköping University Electronic Press, Linköpings universitet. 65 pages.
Link to Book: http://www.ep.liu.se/ecp/035/

[33] Full text  Rickard Karlsson, Thomas Schön, David Törnqvist, Gianpolo Conte and Fredrik Gustafsson. 2008.
Utilizing Model Structure for Efficient Simultaneous Localization and Mapping for a UAV Application.
Technical Report. In series: LiTH-ISY-R #2836. Linköping University Electronic Press. 10 pages.

This contribution aims at unifying two recent trends in applied particle filtering (PF). The first trend is the major impact in simultaneous localization and mapping (SLAM) applications, utilizing the FastSLAM algorithm. Thesecond one is the implications of the marginalized particle filter (MPF) or the Rao-Blackwellized particle filter (RBPF) in positioning and tracking applications. Using the standard FastSLAM algorithm, only low-dimensional vehicle modelsare computationally feasible. In this work, an algorithm is introduced which merges FastSLAM and MPF, and the result is an algorithm for SLAM applications, where state vectors of higher dimensions can be used. Results using experimental data from a UAV (helicopter) are presented. The algorithmfuses measurements from on-board inertial sensors (accelerometer and gyro) and vision in order to solve the SLAM problem, i.e., enable navigation over a long period of time.

[32] Full text  Erik Sandewall. 2008.
A Review of the Handbook of Knowledge Representation.
Artificial Intelligence, 172(18):1965–1966. Elsevier.
DOI: 10.1016/j.artint.2008.10.002.

The newly appeared Handbook of Knowledge Representation is an impressive piece of work. Its three editors and its forty-five contributors have produced twenty-five concise, textbook-style chapters that introduce most of the major aspects of the science of knowledge representation. Reading this book is a very positive experience: it demonstrates the breadth, the depth and the coherence that our field has achieved by now.

[31] Oleg Burdakov, Kaj Holmberg and Per-Magnus Olsson. 2008.
A Dual Ascent Method for the Hop-constrained Shortest Path with Application to Positioning of Unmanned Aerial Vehicles.
Technical Report. In series: Report / Department of Mathematics, Universitetet i Linköping, Tekniska högskolan #2008:7. Linköping University Electronic Press. 30 pages.

We study the problem of positioning unmanned aerial vehicles (UAVs) to maintain an unobstructed flow of communication from a surveying UAV to some base station through the use of multiple relay UAVs. This problem can be modeled as a hopconstrained shortest path problem in a large visibility graph. We propose a dual ascent method for solving this problem, optionally within a branch-and-bound framework. Computational tests show that realistic problems can be solved in a reasonably short time, and that the proposed method is faster than the classical dynamic programming approach.

[30] Mariusz Wzorek and Patrick Doherty. 2007.
A framework for reconfigurable path planning for autonomous unmanned aerial vehicles.
Manuscript (preprint).

[29] Ewa Orlowska, Alberto Policriti and Andrzej Szalas. 2006.
Algebraic and Relational Deductive Tools.
Conference Proceedings. In series: Journal of Applied Non-Classical Logics #??. Éditions Hermès-Lavoisier.
Note: Special Issue

[28] Patrick Doherty, John Mylopoulos and Christopher Welty. 2006.
Proceedings of the 10th International Conference on Principles of Knowledge Representation and Reasoning.
Conference Proceedings. AAAI Press. ISBN: 978-1-57735-281-5.

he National Conference on Artificial Intelligence remains the bellwether for research in artificial intelligence. Leading AI researchers and practitioners as well as scientists and engineers in related fields present theoretical, experimental, and empirical results, covering a broad range of topics that include principles of cognition, perception, and action; the design, application, and evaluation of AI algorithms and systems; architectures and frameworks for classes of AI systems; and analyses of tasks and domains in which intelligent systems perform. The Innovative Applications of Artificial Intelligence conference highlights successful applications of AI technology; explores issues, methods, and lessons learned in the development and deployment of AI applications; and promotes an interchange of ideas between basic and applied AI. This volume presents the proceedings of the latest conferences, held in July, 2006.

[27] Erik Johan Sandewall. 2005.
Leonardo, an Approach towards the Consolidation of Computer Software System.

Note: Research Article, CAISOR Archival Website, Number 2005-016

[26] Patrick Doherty, W. Lukaszewicz, Skowron Andrzej and Andrzej Szalas. 2003.
Knowledge Representation and Approximate Reasoning.
Conference Proceedings. In series: Fundamenta Informaticae #2003(57):2-4. IOS Press.
Note: Special Issue

[25] Full text  Madelaine Engström, Anders Haraldsson, Tove Mattsson and Minna Salminen-Karlsson. 2003.
Studenter genusgranskar sin utbildning: Projekt med elektro- och dataprogrammen och lärarutbildningen vid Linköpings universitet.
Technical Report. In series: CUL-rapporter #2003:5. Linköping University Electronic Press. 56 pages.

I huvudsak kvinnliga studenter från elektro- och dataprogrammen och lä-rarutbildningen utbildades i genuskunskap och fick i uppdrag att under ett läsår studera sina utbildningar ur ett genusperspektiv gällande inne-håll, kurslitteratur, undervisnings- och examinationsformer samt bemö-tande från lärare och andra studenter. Studenterna från respektive utbild-ningsområde bildade var sin projektgrupp under ledning av en handledare.De huvudsakliga resultaten är dels att de kvinnliga studenterna efter utbildningen i genuskunskap och alla diskussioner ser sina utbildningar på ett nytt sätt, genom att självmant observera och reflektera över förete-elser de inte varit medvetna om. Dels har vi fått ökad kunskap om genus-aspekter i själva utbildningsprogrammen genom de observationer som studenterna gjort under läsåret. Dessutom kan man se projektet som en mall för andra program som man vill studera och genomlysa ur ett ge-nusperspektiv. Ett annat intressant resultat från projektet var bildandet av det kvinnliga nätverket Grace för elektro- och datastudenterna.<em>Rapporten beskriver projektet, dess uppläggning och genomförande, re-sultaten från respektive utbildningsområde och avslutas med en reflektion av projektet och de funna resultaten i ett större perspektiv med jämförelser med resultat från andra undersökningar om genus i högskoleutbildning.</em>

[24] Ewa Orlowska and Andrzej Szalas. 2001.
Relational Methods for Computer Science Applications.
In series: Studies in Fuziness and Soft Computing #??. Springer Physica Verlag. 297 pages. ISBN: 37-9081-365-6, 978-37-9081-365-4.
Find book in another country/Hitta boken i ett annat land: http://www.worldcat.org/search?q=37-9081...

This volume addresses all current aspects of relational methods and their applications in computer science. It presents a broad variety of fields and issues in which theories of relations provide conceptual or technical tools. The contributions address such subjects as relational methods in programming, relational constraints, relational methods in linguistics and spatial reasoning, relational modelling of uncertainty. All contributions provide the readers with new and original developments in the respective fields.The reader thus gets an interdisciplinary spectrum of the state of the art of relational methods and implementation-oriented solutions of problems related to these areas

[23] Erik Johan Sandewall. 2000.
M. Shanahan, Solving the Frame Problem.
Artificial Intelligence, 123(1-2):271–273.
DOI: 10.1016/S0004-3702(00)00058-8.

[22] Full text  Fredrik Tjärnström, Mattias Duppils, Patrik Haslum, David Byers, Gundars Kulups and Dan Lawesson. 1999.
ENSYM-Project Oriented Studies of spring 98 - team 1.
Technical Report. In series: LiTH-ISY-R #2094. Linköping University Electronic Press. 14 pages.

The report is description of the ENSYM Project Oriented Studies(POS) of spring 1998. The project goal was to control a toy cararound a not beforehand given track as fast as possible.

[21] Full text  Thord Andersson, Silvia Coradeschi and Alessandro Saffiotti. 1999.
Fuzzy matching of visual cues in an unmanned airborne vehicle.
Technical Report. Linköping University, Department of Electrical Engineering.

Computer vision systems used in autonomous mobile vehicles are typically linked to higher-level deliberation processes. One important aspect of this link is how to connect, or anchor, the symbols used at the higher level to the objects in the vision system that these symbols refer to. Anchoring is complicated by the fact that the vision data are inherently affected by uncertainty. We propose an anchoring technique that uses fuzzy sets to represent the uncertainty in the perceptual data. We show examples where this technique allows a deliberative system to reason about the objects (cars) detected by a vision system embarked in an unmanned helicopter, in the framework of the Witas project.

[20] Full text  Patrick Doherty and Joakim Gustafsson. 1998.
Delayed effects of actions = direct effects + causal rules.
Technical Report. In series: Linköping Electronic Articles in Computer and Information Science #98-001. Linköping University Electronic Press.
Link: http://www.ep.liu.se/ea/cis/1998/001/

<strong></strong> We propose an approach to modeling delayed effects of actions which is based on the use of causal constraints and their interaction with the direct effects of actions. The approach extends previous work with a causal approach used to deal with the ramification problem. We show the similarity between solutions to the modeling of indirect effects and delayed effects of actions by example. The base logic PMON+ is a temporal logic for reasoning about action and change and uses circumscription. It is shown that the extension for delayed effects of actions retains the first-order reducibility property shown previously for successfully dealing with the frame and ramification problems for a large class of action scenarios. We also consider the “causal qualification” problem, \"natural death\" of fluents and causal lag, each of which is closely related to the use of delayed effects.

[19] Erik Sandewall. 1997.
Strategies and policies of Linköping University Electronic Press.
Technical Report. In series: Linköping Electronic Articles on Academic Policies and Trends #1 Vol. 1. Linköping University Electronic Press. 15 pages.

Linköping University has recently created a separate entity, called <em>Linköping University Electronic Press</em>, for the <em>unrefereed electronic publication</em> of research articles and other university-related materials over the Internet. The present article presents the background for why the E-Press was created and the strategies which have been chosen for its operation at least during its initial period. The article identifies three key problems in the context of this strategy: <ul><li>The purely <em>formal problems</em> concerning what counts as a publication;</li><li>The <em>persistence problem</em> of making sure that an electronically published article does not change over time;</li><li>The <em>reception problems</em> concerning how fellow researchersand the academic community regard electronically published articles.</li></ul>We describe how the formal problems and the persistence problems have been addressed in the E-Press initiative. With respect to the reception problems, we argue that scientific journals and journal-like conferences presently perform four distinct functions, and that these functions can be performed better if they are “unbundled” and addressed by other means. The four functions are:<ul><li>Publication in the narrow sense - making the article publicly available;</li><li>Scientific quality control through reviewing;</li><li>Selection of relevant articles for the benefit of the researcher-reader;</li><li>Promotion of the scientific results of the author.</li></ul>The Electronic Press focusses on the first one of these four functions. We discuss how the other three functions can be separated and performed by other means than through a conventional journal or quality conference proceedings.

[18] Full text  Erik Sandewall. 1997.
A Neo-Classical Structure for Scientific Publication and Reviewing.
Technical Report. In series: Linköping Electronic Articles on Academic Policies and Trends #1 Vol, 2. Linköping University Electronic Press. 28 pages.

I propose a <em>neo-classical</em> structure for publishing and reviewing of scientific works. This proposal has the following characteristic components:<ul><li>Electronic “preprint archives” and other similar mechanisms where research articles are made publicly available without prior formal review are considered as true and full-fledged <em>publication</em> of research from the point of view of priority of results.</li><li>Large parts of the reviewing process is done publicly and in the form of published review letters and other contributions to the scientific debate, rather than through anonymous and confidential review statements which dominate today. There is a switch from anonymous “pass-fail” reviewing towards <em>open reviewing</em> where the identity and the comments of the reviewers are made public.</li><li>Since open reviewing happens <em>after</em> publication, rather than before, there is a second step where articles are promoted to “recommended” or “certified” status through the decision of a review committee. The requirements for certification are set at least as high as for the formally published journal articles of today, so that it counts like journal publication in a CV.</li><li>Several techniques are foreseen for facilitating the selection process of the individual reader as well as for improving communication as such between researchers.</li><li>One should accept that there are good reasons why there may be several articles (from the same author) presenting the same result. This suggests the introduction of a formal concept of a “result” which is represented by several publications, and to allow citations to refer to results rather than to some specific publication of the result.</li></ul>I refer to this system as <em>neo-classical</em> because it assumes that peer review is done <em>openly</em> and <em>after</em> an article has been published. It is of course only proposed as a complement which can easily co-exist with the modern system, allowing each author to choose which of the two systems he or she wishes to use for a particular article.

[17] Wojciech Penczek and Andrzej Szalas. 1996.
Proceedings of the 21st International Symposium on Mathematical Foundations of Computer Science (MFCS).
Conference Proceedings. In series: Lecture Notes in Computer Science #1113. Springer Verlag. ISBN: 978-3-540-61550-7.
Link: http://www.springer.com/computer/foundat...

[16] Full text  Patrick Doherty. 1996.
PMON+: A fluent logic for action and change - formal specification, version 1.0.
Technical Report. In series: LITH-IDA-R #33. Department of Computer and Information Science, Linköping University.

This report describes the current state of work with PMON, a logic for reasoning about action and change, and its extensions. PMON has been assessed correct for the K-IA class using Sandewall's Features and Fluents framework which provides tools for assessing the correctness of logics of action and change. A syntactic characterization of PMON has previously been provided in terms of a circumscription axiom which is shown to be reducible to a first-order formula. This report introduces a number of new extensions which are also reducible and deal with ramification. The report is intended to provide a formal specification for the PMON family of logics and the surface language L(SD) used to represent action scenario descriptions. It should be considered a working draft. The title of the report has a version number because both the languages and logics used are continually evolving. Since this document is intended as a formal specification which is used by our group as a reference for research and implementation, it is understandably brief as regards intuitions and applications of the languages and logics defined. We do provide a set of benchmarks and comments concerning these which can serve as a means of comparing this formalism with others. The set of benchmarks is not complete and is only intended to provide representative examples of the expressivity and use of this particular family of logics. We describe its features and limitations in other publications by our group which can normally be found at \"http://www.ida.liu.se/labs/kplab/\".

[15] Full text  Patrick Doherty, Witold Lukaszewicz and Andrzej Szalas. 1996.
Declarative ptime queries to relational databases.
Technical Report. In series: LITH-IDA-R #34. Department of Computer and Information Science, Linköping University.

[14] Full text  John-Jules Meyer and Patrick Doherty. 1996.
Preferential action semantics, preliminary report.
Technical Report. In series: LITH-IDA-R #??. Department of Computer and Information Science, Linköping University.

In this paper, we propose a new way of considering reasoning about action and change. Rather than placing a preferential structure onto the models of logical theories, we place such a structure directly on the semantics of the actions involved. In this way, we obtain a preferential semantics of actions by means of which we can not only deal with several of the traditional problems in this area such as the frame and ramification problems, but can generalize these solutions to a context which includes both nondeterministic and concurrent actions. In fact, the net result is an integration of semantical and verificational techniques from the paradigm of imperative and concurrent programs in particular, as known from traditional programming, with the AI perspective. In this paper, the main focus is on semantical (i.e. model theoretical) issues rather than providing a logical calculus, which would be the next step in the endeavor.

[13] Full text  Patrick Doherty, Witold Lukaszewicz and Andrzej Szalas. 1996.
General domain circumscription and its first-order reduction.
Technical Report. In series: LITH-IDA-R #1. Department of Computer and Information Science, Linköping University.

[12] Leonard Bolc and Andrzej Szalas. 1995.
Time and Logic: A Computational Approach.
CRC Press. 325 pages. ISBN: 1-85728-233-7, 978-18-5728-233-7.
Find book at a Swedish library/Hitta boken i ett svenskt bibliotek: http://libris.kb.se/hitlist?d=libris&q= ...
Find book in another country/Hitta boken i ett annat land: http://www.worldcat.org/search?q= 978-18...

Time and logic are central driving concepts in science and technology. In this book, some of the major current developments in our understanding and application of temporal logic are presented in computational terms. \"Time and Logic: A Computational Approach\" should be a useful sourcebook for those within the specific field of temporal logic, as well as providing valuable introductory material for those seeking an entry into this increasingly important area of theoretical computing.; The emphasis of the book is on presenting a broad range of approaches to computational applications. The techniques used will also be applicable in many cases to formalize beyond temporal logic alone, and it is hoped that adaptation to many different logics of programmes will be facilitated. Throughout, the authors have kept implementation-oriented solutions in mind.; The book begins with an introduction to the basic ideas of temporal logic. Successive chapters then examine particular aspects of the temporal theoretical computing domain, relating their applications to familiar areas of research, such as stochastic process theory, automata theory, established proof systems, model checking, relational logic and classical predicate logic. This should be a useful addition to the library of all theoretical computer scientists, providing a synthesis of well established results in temporal logic with the most up-to-date findings of some of the world's leading theoreticians.

[11] Full text  Patrick Doherty, Witold Lukaszewicz and Andrzej Szalas. 1995.
A characterization result for circumscribed normal logic programs. Revised version accepted for publication: Special issue of honor of H. Rasiowa, Fundamenta Informaticae.
Technical Report. In series: LITH-IDA-R #20. Department of Computer and Information Science, Linköping University.

[10] Full text  Patrick Doherty, Witold Lukaszewicz and Andrzej Szalas. 1994.
Computing circumscription revisited: A reduction algorithm.
Technical Report. In series: LITH-IDA-R #94-42. Department of Computer and Information Science, Linköping University.

In recent years, a great deal of attention has been devoted to logics of \"commonsense\" reasoning. Among the candidates proposed, circumscription has been perceived as an elegant mathematical technique for modeling nonmonotonic reasoning, but difficult to apply in practice. The major reason for this is the nd-order nature of circumscription axioms and the difficulty in finding proper substitutions of predicate expressions for predicate variables. One solution to this problem is to compile, where possible, nd-order formulas into equivalent 1st-order formulas. Although some progress has been made using this approach, the results are not as strong as one might desire and they are isolated in nature. In this article, we provide a general method which can be used in an algorithmic manner to reduce circumscription axioms to 1st-order formulas. The algorithm takes as input an arbitrary 2nd-order formula and either returns as output an equivalent 1st-order formula, or terminates with failure. The class of 2nd-order formulas, and analogously the class of circumscriptive theories which can be reduced, provably subsumes those covered by existing results. We demonstrate the generality of the algorithm using circumscriptive theories with mixed quantifiers (some involving Skolemization), variable constants, non-separated formulas, and formulas with n-ary predicate variables. In addition, we analyze the strength of the algorithm and compare it with existing approaches providing formal subsumption results.

[9] Patrick Doherty. 1994.
Notes on PMON circumscription.
Technical Report. In series: LITH-IDA-R #43. Department of Computer and Information Science, Linköping University.

[8] Patrick Doherty and Witold Lukaszewicz. 1992.
FONML3 - A first-order non-monotonic logic with explicit defaults.
Technical Report. In series: LITH-IDA-R #20. Department of Computer and Information Science, Linköping University.

[7] Patrick Doherty, Dimiter Driankov and H. Hellendoorn. 1992.
Fuzzy if-then-unless rules and their implementation.
Technical Report. In series: LITH-IDA-R #21. Department of Computer and Information Science, Linköping University.

[6] Patrick Doherty, Dimiter Driankov and A. Tsoukias. 1992.
Partiality, para-consistency and preference modeling: Preliminary version.
Technical Report. In series: LITH-IDA-R #18. Department of Computer and Information Systems, Linköping University.

[5] Patrick Doherty. 1992.
A constraint-based approach to proof procedures for multi-valued logics.
Technical Report. In series: LITH-IDA-R #2. Department of Computer and Information Science, Linköping university, Linköping, Sweden.

[4] Patrick Doherty and Witold Lukaszewicz. 1991.
NML3 - A non-monotonic logic with explicit defaults.
Technical Report. In series: Användarrapport #13. Department of Computer and Information Science, Linköping University.

[3] Patrick Doherty. 1990.
NM3 - A three-valued non-monotonic formalism. Preliminary report.
Technical Report. In series: LITH-IDA-R #44. Department of Computer and Information Science, Linköping University.

[2] Patrick Doherty. 1990.
A correspondence between inheritance hierarchies and a logic of preferential entailment.
Technical Report. In series: LITH-IDA-R #??. Department of Computer and Information Science, Linköping University.

[1] Patrick Doherty. 1985.
A rule interpreter for an emycin-like expert system tool.
Technical Report. In series: Aslab Memo #85-05. Linköpings tekniska högskola.

Page responsible: Patrick Doherty
Last updated: 2014-04-30