@phdthesis{Chen2023, author = {Chen, Junchao}, title = {A self-adaptive resilient method for implementing and managing the high-reliability processing system}, doi = {10.25932/publishup-58313}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-583139}, school = {Universit{\"a}t Potsdam}, pages = {XXIII, 167}, year = {2023}, abstract = {As a result of CMOS scaling, radiation-induced Single-Event Effects (SEEs) in electronic circuits became a critical reliability issue for modern Integrated Circuits (ICs) operating under harsh radiation conditions. SEEs can be triggered in combinational or sequential logic by the impact of high-energy particles, leading to destructive or non-destructive faults, resulting in data corruption or even system failure. Typically, the SEE mitigation methods are deployed statically in processing architectures based on the worst-case radiation conditions, which is most of the time unnecessary and results in a resource overhead. Moreover, the space radiation conditions are dynamically changing, especially during Solar Particle Events (SPEs). The intensity of space radiation can differ over five orders of magnitude within a few hours or days, resulting in several orders of magnitude fault probability variation in ICs during SPEs. This thesis introduces a comprehensive approach for designing a self-adaptive fault resilient multiprocessing system to overcome the static mitigation overhead issue. This work mainly addresses the following topics: (1) Design of on-chip radiation particle monitor for real-time radiation environment detection, (2) Investigation of space environment predictor, as support for solar particle events forecast, (3) Dynamic mode configuration in the resilient multiprocessing system. Therefore, according to detected and predicted in-flight space radiation conditions, the target system can be configured to use no mitigation or low-overhead mitigation during non-critical periods of time. The redundant resources can be used to improve system performance or save power. On the other hand, during increased radiation activity periods, such as SPEs, the mitigation methods can be dynamically configured appropriately depending on the real-time space radiation environment, resulting in higher system reliability. Thus, a dynamic trade-off in the target system between reliability, performance and power consumption in real-time can be achieved. All results of this work are evaluated in a highly reliable quad-core multiprocessing system that allows the self-adaptive setting of optimal radiation mitigation mechanisms during run-time. Proposed methods can serve as a basis for establishing a comprehensive self-adaptive resilient system design process. Successful implementation of the proposed design in the quad-core multiprocessor shows its application perspective also in the other designs.}, language = {en} } @phdthesis{Nordmann2020, author = {Nordmann, Paul-Patrick}, title = {Fehlerkorrektur von Speicherfehlern mit Low-Density-Parity-Check-Codes}, doi = {10.25932/publishup-48048}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-480480}, school = {Universit{\"a}t Potsdam}, pages = {IV, 99, XII}, year = {2020}, abstract = {Die Fehlerkorrektur in der Codierungstheorie besch{\"a}ftigt sich mit der Erkennung und Behebung von Fehlern bei der {\"U}bertragung und auch Sicherung von Nachrichten. Hierbei wird die Nachricht durch zus{\"a}tzliche Informationen in ein Codewort kodiert. Diese Kodierungsverfahren besitzen verschiedene Anspr{\"u}che, wie zum Beispiel die maximale Anzahl der zu korrigierenden Fehler und die Geschwindigkeit der Korrektur. Ein g{\"a}ngiges Codierungsverfahren ist der BCH-Code, welches industriell f{\"u}r bis zu vier Fehler korrigiere Codes Verwendung findet. Ein Nachteil dieser Codes ist die technische Durchlaufzeit f{\"u}r die Berechnung der Fehlerstellen mit zunehmender Codel{\"a}nge. Die Dissertation stellt ein neues Codierungsverfahren vor, bei dem durch spezielle Anordnung kleinere Codel{\"a}ngen eines BCH-Codes ein langer Code erzeugt wird. Diese Anordnung geschieht {\"u}ber einen weiteren speziellen Code, einem LDPC-Code, welcher f{\"u}r eine schneller Fehlererkennung konzipiert ist. Hierf{\"u}r wird ein neues Konstruktionsverfahren vorgestellt, welches einen Code f{\"u}r einen beliebige L{\"a}nge mit vorgebbaren beliebigen Anzahl der zu korrigierenden Fehler vorgibt. Das vorgestellte Konstruktionsverfahren erzeugt zus{\"a}tzlich zum schnellen Verfahren der Fehlererkennung auch eine leicht und schnelle Ableitung eines Verfahrens zu Kodierung der Nachricht zum Codewort. Dies ist in der Literatur f{\"u}r die LDPC-Codes bis zum jetzigen Zeitpunkt einmalig. Durch die Konstruktion eines LDPC-Codes wird ein Verfahren vorgestellt wie dies mit einem BCH-Code kombiniert wird, wodurch eine Anordnung des BCH-Codes in Bl{\"o}cken erzeugt wird. Neben der allgemeinen Beschreibung dieses Codes, wird ein konkreter Code f{\"u}r eine 2-Bitfehlerkorrektur beschrieben. Diese besteht aus zwei Teilen, welche in verschiedene Varianten beschrieben und verglichen werden. F{\"u}r bestimmte L{\"a}ngen des BCH-Codes wird ein Problem bei der Korrektur aufgezeigt, welche einer algebraischen Regel folgt. Der BCH-Code wird sehr allgemein beschrieben, doch existiert durch bestimmte Voraussetzungen ein BCH-Code im engerem Sinne, welcher den Standard vorgibt. Dieser BCH-Code im engerem Sinne wird in dieser Dissertation modifiziert, so dass das algebraische Problem bei der 2-Bitfehler Korrektur bei der Kombination mit dem LDPC-Code nicht mehr existiert. Es wird gezeigt, dass nach der Modifikation der neue Code weiterhin ein BCH-Code im allgemeinen Sinne ist, welcher 2-Bitfehler korrigieren und 3-Bitfehler erkennen kann. Bei der technischen Umsetzung der Fehlerkorrektur wird des Weiteren gezeigt, dass die Durchlaufzeiten des modifizierten Codes im Vergleich zum BCH-Code schneller ist und weiteres Potential f{\"u}r Verbesserungen besitzt. Im letzten Kapitel wird gezeigt, dass sich dieser modifizierte Code mit beliebiger L{\"a}nge eignet f{\"u}r die Kombination mit dem LDPC-Code, wodurch dieses Verfahren nicht nur umf{\"a}nglicher in der L{\"a}nge zu nutzen ist, sondern auch durch die schnellere Dekodierung auch weitere Vorteile gegen{\"u}ber einem BCH-Code im engerem Sinne besitzt.}, language = {de} } @article{TavakoliAlirezazadehHedayatipouretal.2021, author = {Tavakoli, Hamad and Alirezazadeh, Pendar and Hedayatipour, Ava and Nasib, A. H. Banijamali and Landwehr, Niels}, title = {Leaf image-based classification of some common bean cultivars using discriminative convolutional neural networks}, series = {Computers and electronics in agriculture : COMPAG online ; an international journal}, volume = {181}, journal = {Computers and electronics in agriculture : COMPAG online ; an international journal}, publisher = {Elsevier}, address = {Amsterdam [u.a.]}, issn = {0168-1699}, doi = {10.1016/j.compag.2020.105935}, pages = {11}, year = {2021}, abstract = {In recent years, many efforts have been made to apply image processing techniques for plant leaf identification. However, categorizing leaf images at the cultivar/variety level, because of the very low inter-class variability, is still a challenging task. In this research, we propose an automatic discriminative method based on convolutional neural networks (CNNs) for classifying 12 different cultivars of common beans that belong to three various species. We show that employing advanced loss functions, such as Additive Angular Margin Loss and Large Margin Cosine Loss, instead of the standard softmax loss function for the classification can yield better discrimination between classes and thereby mitigate the problem of low inter-class variability. The method was evaluated by classifying species (level I), cultivars from the same species (level II), and cultivars from different species (level III), based on images from the leaf foreside and backside. The results indicate that the performance of the classification algorithm on the leaf backside image dataset is superior. The maximum mean classification accuracies of 95.86, 91.37 and 86.87\% were obtained at the levels I, II and III, respectively. The proposed method outperforms the previous relevant works and provides a reliable approach for plant cultivars identification.}, language = {en} } @phdthesis{Morozov2005, author = {Morozov, Alexei}, title = {Optimierung von Fehlererkennungsschaltungen auf der Grundlage von komplement{\"a}ren Erg{\"a}nzungen f{\"u}r 1-aus-3 und Berger Codes}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-5360}, school = {Universit{\"a}t Potsdam}, year = {2005}, abstract = {Die Dissertation stellt eine neue Herangehensweise an die L{\"o}sung der Aufgabe der funktionalen Diagnostik digitaler Systeme vor. In dieser Arbeit wird eine neue Methode f{\"u}r die Fehlererkennung vorgeschlagen, basierend auf der Logischen Erg{\"a}nzung und der Verwendung von Berger-Codes und dem 1-aus-3 Code. Die neue Fehlererkennungsmethode der Logischen Erg{\"a}nzung gestattet einen hohen Optimierungsgrad der ben{\"o}tigten Realisationsfl{\"a}che der konstruierten Fehlererkennungsschaltungen. Außerdem ist eins der wichtigen in dieser Dissertation gel{\"o}sten Probleme die Synthese vollst{\"a}ndig selbstpr{\"u}fender Schaltungen.}, subject = {logische Erg{\"a}nzung}, language = {de} } @article{GerberGoessel1994, author = {Gerber, Stefan and G{\"o}ssel, Michael}, title = {Detection of permanent faults of a floating point adder by pseudoduplication}, year = {1994}, language = {en} } @article{BhattacharyaDimitrievGoessel2000, author = {Bhattacharya, M. K. and Dimitriev, Alexej and G{\"o}ssel, Michael}, title = {Zero-aliasing space compresion using a single periodic output and its application to testing of embedded}, year = {2000}, language = {en} } @article{DimitrievSaposhnikovSaposhnikovetal.1999, author = {Dimitriev, Alexej and Saposhnikov, V. V. and Saposhnikov, Vl. V. and G{\"o}ssel, Michael}, title = {Concurrent checking of sequential circuits by alternating inputs}, year = {1999}, language = {en} } @article{KuentzerKrstić2020, author = {Kuentzer, Felipe A. and Krstić, Miloš}, title = {Soft error detection and correction architecture for asynchronous bundled data designs}, series = {IEEE transactions on circuits and systems}, volume = {67}, journal = {IEEE transactions on circuits and systems}, number = {12}, publisher = {Institute of Electrical and Electronics Engineers}, address = {New York}, issn = {1549-8328}, doi = {10.1109/TCSI.2020.2998911}, pages = {4883 -- 4894}, year = {2020}, abstract = {In this paper, an asynchronous design for soft error detection and correction in combinational and sequential circuits is presented. The proposed architecture is called Asynchronous Full Error Detection and Correction (AFEDC). A custom design flow with integrated commercial EDA tools generates the AFEDC using the asynchronous bundled-data design style. The AFEDC relies on an Error Detection Circuit (EDC) for protecting the combinational logic and fault-tolerant latches for protecting the sequential logic. The EDC can be implemented using different detection methods. For this work, two boundary variants are considered, the Full Duplication with Comparison (FDC) and the Partial Duplication with Parity Prediction (PDPP). The AFEDC architecture can handle single events and timing faults of arbitrarily long duration as well as the synchronous FEDC, but additionally can address known metastability issues of the FEDC and other similar synchronous architectures and provide a more practical solution for handling the error recovery process. Two case studies are developed, a carry look-ahead adder and a pipelined non-restoring array divider. Results show that the AFEDC provides equivalent fault coverage when compared to the FEDC while reducing area, ranging from 9.6\% to 17.6\%, and increasing energy efficiency, which can be up to 6.5\%.}, language = {en} } @article{SaposhnikovOtscheretnijSaposhnikovetal.1998, author = {Saposhnikov, Vl. V. and Otscheretnij, Vitalij and Saposhnikov, V. V. and G{\"o}ssel, Michael}, title = {Design of Fault-Tolerant Circuits by self-dual Duplication}, year = {1998}, language = {en} } @article{MoschaninSaposhnikovSaposhnikovetal.1996, author = {Moschanin, Wladimir and Saposhnikov, Vl. V. and Saposhnikov, Va. V. and G{\"o}ssel, Michael}, title = {Synthesis of self-dual multi-output combinational circuits for on-line Teting}, year = {1996}, language = {en} } @article{SeuringGoesselSogomonyan1998, author = {Seuring, Markus and G{\"o}ssel, Michael and Sogomonyan, Egor S.}, title = {Ein strukturelles Verfahren zur Kompaktierung von Schaltungsausgaben f{\"u}r online-Fehlererkennungen und Selbstests}, year = {1998}, language = {de} } @article{SogomonyanGoessel1996, author = {Sogomonyan, Egor S. and G{\"o}ssel, Michael}, title = {Concurrently self-testing embedded checkers for ultra-reliable fault-tolerant systems}, year = {1996}, language = {en} } @article{MorosovGoesselHartje1999, author = {Morosov, Andrej and G{\"o}ssel, Michael and Hartje, Hendrik}, title = {Reduced area overhead of the input party for code-disjoint circuits}, year = {1999}, language = {en} } @article{SeuringGoessel1999, author = {Seuring, Markus and G{\"o}ssel, Michael}, title = {A structural method for output compaction of sequential automata implemented as circuits}, year = {1999}, language = {en} } @book{SeuringGoessel1998, author = {Seuring, Markus and G{\"o}ssel, Michael}, title = {A structural approach for space compaction for sequential circuits}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Informatik}, volume = {1998, 05}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Informatik}, publisher = {Univ.}, address = {Potsdam}, issn = {0946-7580}, pages = {16 Bl. : graph. Darst.}, year = {1998}, language = {en} } @article{HlawiczkaGoesselSogomonyan1997, author = {Hlawiczka, A. and G{\"o}ssel, Michael and Sogomonyan, Egor S.}, title = {A linear code-preserving signature analyzer COPMISR}, isbn = {0-8186-7810-0}, year = {1997}, language = {en} } @article{BogueGoesselJuergensenetal.1998, author = {Bogue, Ted and G{\"o}ssel, Michael and J{\"u}rgensen, Helmut and Zorian, Yervant}, title = {Built-in self-Test with an alternating output}, isbn = {0-8186-8359-7}, year = {1998}, language = {en} } @article{OtscheretnijGoesselSaposhnikovetal.1998, author = {Otscheretnij, Vitalij and G{\"o}ssel, Michael and Saposhnikov, Vl. V. and Saposhnikov, V. V.}, title = {Fault-tolerant self-dual circuits with error detection by parity- and group parity prediction}, year = {1998}, language = {en} } @article{SogomonyanSinghGoessel1998, author = {Sogomonyan, Egor S. and Singh, Adit D. and G{\"o}ssel, Michael}, title = {A multi-mode scannable memory element for high test application efficiency and delay testing}, year = {1998}, language = {en} } @article{DimitrievSaposhnikovGoesseletal.1997, author = {Dimitriev, Alexej and Saposhnikov, Vl. V. and G{\"o}ssel, Michael and Saposhnikov, V. V.}, title = {Self-dual duplication - a new method for on-line testing}, year = {1997}, language = {en} } @article{SaposhnikovMoshaninSaposhnikovetal.1997, author = {Saposhnikov, Vl. V. and Moshanin, Vl. and Saposhnikov, V. V. and G{\"o}ssel, Michael}, title = {Self-dual multi output combinational circuits with output data compaction}, year = {1997}, language = {en} } @book{SeuringGoesselSogomonyan1997, author = {Seuring, Markus and G{\"o}ssel, Michael and Sogomonyan, Egor S.}, title = {A structural approach for space compaction for concurrent checking and BIST}, series = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Informatik}, volume = {1997, 01}, journal = {Preprint / Universit{\"a}t Potsdam, Institut f{\"u}r Informatik}, publisher = {Univ. Potsdam}, address = {Potsdam [u.a.]}, issn = {0946-7580}, pages = {19 S. : Ill.}, year = {1997}, language = {en} } @article{GoesselSogomonyan1998, author = {G{\"o}ssel, Michael and Sogomonyan, Egor S.}, title = {On-line Test auf der Grundlage eines die Parit{\"a}t erhaltenden Signaturanalysators}, year = {1998}, language = {de} } @article{MorosovSaposhnikovGoessel1998, author = {Morosov, Andrej and Saposhnikov, V. V. and G{\"o}ssel, Michael}, title = {Self-Checking circuits with unidiectionally independent outputs}, year = {1998}, language = {en} } @article{KrstićWeidlingPetrovicetal., author = {Krstić, Miloš and Weidling, Stefan and Petrovic, Vladimir and Sogomonyan, Egor S.}, title = {Enhanced architectures for soft error detection and correction in combinational and sequential circuits}, series = {Microelectronics Reliability}, volume = {56}, journal = {Microelectronics Reliability}, issn = {0026-2714}, pages = {212 -- 220}, abstract = {In this paper two new methods for the design of fault-tolerant pipelined sequential and combinational circuits, called Error Detection and Partial Error Correction (EDPEC) and Full Error Detection and Correction (FEDC), are described. The proposed methods are based on an Error Detection Logic (EDC) in the combinational circuit part combined with fault tolerant memory elements implemented using fault tolerant master-slave flip-flops. If a transient error, due to a transient fault in the combinational circuit part is detected by the EDC, the error signal controls the latching stage of the flip-flops such that the previous correct state of the register stage is retained until the transient error disappears. The system can continue to work in its previous correct state and no additional recovery procedure (with typically reduced clock frequency) is necessary. The target applications are dataflow processing blocks, for which software-based recovery methods cannot be easily applied. The presented architectures address both single events as well as timing faults of arbitrarily long duration. An example of this architecture is developed and described, based on the carry look-ahead adder. The timing conditions are carefully investigated and simulated up to the layout level. The enhancement of the baseline architecture is demonstrated with respect to the achieved fault tolerance for the single event and timing faults. It is observed that the number of uncorrected single events is reduced by the EDPEC architecture by 2.36 times compared with previous solution. The FEDC architecture further reduces the number of uncorrected events to zero and outperforms the Triple Modular Redundancy (TMR) with respect to correction of timing faults. The power overhead of both new architectures is about 26-28\% lower than the TMR.}, language = {en} } @phdthesis{Klockmann2022, author = {Klockmann, Alexander}, title = {Modifizierte Unidirektionale Codes f{\"u}r Speicherfehler}, pages = {92}, year = {2022}, abstract = {Das Promotionsvorhaben verfolgt das Ziel, die Zuverl{\"a}ssigkeit der Datenspeicherung und die Speicherdichte von neu entwickelten Speichern (Emerging Memories) mit Multi-Level-Speicherzellen zu verbessern bzw. zu erh{\"o}hen. Hierf{\"u}r werden Codes zur Erkennung von unidirektionalen Fehlern analysiert, modifiziert und neu entwickelt, um sie innerhalb der neuen Speicher anwenden zu k{\"o}nnen. Der Fokus liegt dabei auf sog. Berger-Codes und m-aus-n-Codes. Da Multi-Level-Speicherzellen nicht mehr bin{\"a}r, sondern mit mehreren Leveln arbeiten, k{\"o}nnen bisher verwendete Codes nicht mehr verwendet werden, bzw. m{\"u}ssen entsprechend angepasst werden. Auf Basis der Berger-Codes und m-aus-n-Codes werden in dieser Arbeit neue Codes abgeleitet, welche in der Lage sind, Daten auch in mehrwertigen Systemen zu sch{\"u}tzen.}, language = {de} } @misc{Fandino2019, author = {Fandi{\~n}o, Jorge}, title = {Founded (auto)epistemic equilibrium logic satisfies epistemic splitting}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1060}, issn = {1866-8372}, doi = {10.25932/publishup-46968}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-469685}, pages = {671 -- 687}, year = {2019}, abstract = {In a recent line of research, two familiar concepts from logic programming semantics (unfounded sets and splitting) were extrapolated to the case of epistemic logic programs. The property of epistemic splitting provides a natural and modular way to understand programs without epistemic cycles but, surprisingly, was only fulfilled by Gelfond's original semantics (G91), among the many proposals in the literature. On the other hand, G91 may suffer from a kind of self-supported, unfounded derivations when epistemic cycles come into play. Recently, the absence of these derivations was also formalised as a property of epistemic semantics called foundedness. Moreover, a first semantics proved to satisfy foundedness was also proposed, the so-called Founded Autoepistemic Equilibrium Logic (FAEEL). In this paper, we prove that FAEEL also satisfies the epistemic splitting property something that, together with foundedness, was not fulfilled by any other approach up to date. To prove this result, we provide an alternative characterisation of FAEEL as a combination of G91 with a simpler logic we called Founded Epistemic Equilibrium Logic (FEEL), which is somehow an extrapolation of the stable model semantics to the modal logic S5.}, language = {en} } @article{CabalarFandinoFarinasdelCerro2021, author = {Cabalar, Pedro and Fandi{\~n}o, Jorge and Fari{\~n}as del Cerro, Luis}, title = {Splitting epistemic logic programs}, series = {Theory and practice of logic programming / publ. for the Association for Logic Programming}, volume = {21}, journal = {Theory and practice of logic programming / publ. for the Association for Logic Programming}, number = {3}, publisher = {Cambridge Univ. Press}, address = {Cambridge [u.a.]}, issn = {1471-0684}, doi = {10.1017/S1471068420000058}, pages = {296 -- 316}, year = {2021}, abstract = {Epistemic logic programs constitute an extension of the stable model semantics to deal with new constructs called subjective literals. Informally speaking, a subjective literal allows checking whether some objective literal is true in all or some stable models. As it can be imagined, the associated semantics has proved to be non-trivial, since the truth of subjective literals may interfere with the set of stable models it is supposed to query. As a consequence, no clear agreement has been reached and different semantic proposals have been made in the literature. Unfortunately, comparison among these proposals has been limited to a study of their effect on individual examples, rather than identifying general properties to be checked. In this paper, we propose an extension of the well-known splitting property for logic programs to the epistemic case. We formally define when an arbitrary semantics satisfies the epistemic splitting property and examine some of the consequences that can be derived from that, including its relation to conformant planning and to epistemic constraints. Interestingly, we prove (through counterexamples) that most of the existing approaches fail to fulfill the epistemic splitting property, except the original semantics proposed by Gelfond 1991 and a recent proposal by the authors, called Founded Autoepistemic Equilibrium Logic.}, language = {en} } @misc{AguadoCabalarFandinoetal.2019, author = {Aguado, Felicidad and Cabalar, Pedro and Fandi{\~n}o, Jorge and Pearce, David and Perez, Gilberto and Vidal, Concepcion}, title = {Revisiting explicit negation in answer set programming}, series = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Postprints der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {1104}, issn = {1866-8372}, doi = {10.25932/publishup-46969}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-469697}, pages = {908 -- 924}, year = {2019}, abstract = {A common feature in Answer Set Programming is the use of a second negation, stronger than default negation and sometimes called explicit, strong or classical negation. This explicit negation is normally used in front of atoms, rather than allowing its use as a regular operator. In this paper we consider the arbitrary combination of explicit negation with nested expressions, as those defined by Lifschitz, Tang and Turner. We extend the concept of reduct for this new syntax and then prove that it can be captured by an extension of Equilibrium Logic with this second negation. We study some properties of this variant and compare to the already known combination of Equilibrium Logic with Nelson's strong negation.}, language = {en} } @phdthesis{Frank2024, author = {Frank, Mario}, title = {On synthesising Linux kernel module components from Coq formalisations}, doi = {10.25932/publishup-64255}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-642558}, school = {Universit{\"a}t Potsdam}, pages = {IX, 78}, year = {2024}, abstract = {This thesis presents an attempt to use source code synthesised from Coq formalisations of device drivers for existing (micro)kernel operating systems, with a particular focus on the Linux Kernel. In the first part, the technical background and related work are described. The focus is here on the possible approaches to synthesising certified software with Coq, namely the extraction to functional languages using the Coq extraction plugin and the extraction to Clight code using the CertiCoq plugin. It is noted that the implementation of CertiCoq is verified, whereas this is not the case for the Coq extraction plugin. Consequently, there is a correctness guarantee for the generated Clight code which does not hold for the code being generated by the Coq extraction plugin. Furthermore, the differences between user space and kernel space software are discussed in relation to Linux device drivers. It is elaborated that it is not possible to generate working Linux kernel module components using the Coq extraction plugin without significant modifications. In contrast, it is possible to produce working user space drivers both with the Coq extraction plugin and CertiCoq. The subsequent parts describe the main contributions of the thesis. In the second part, it is demonstrated how to extend the Coq extraction plugin to synthesise foreign function calls between the functional language OCaml and the imperative language C. This approach has the potential to improve the type-safety of user space drivers. Furthermore, it is shown that the code being synthesised by CertiCoq cannot be used in kernel space without modifications to the necessary runtime. Consequently, the necessary modifications to the runtimes of CertiCoq and VeriFFI are introduced, resulting in the runtimes becoming compatible components of a Linux kernel module. Furthermore, justifications for the transformations are provided and possible further extensions to both plugins and solutions to failing garbage collection calls in kernel space are discussed. The third part presents a proof of concept device driver for the Linux Kernel. To achieve this, the event handler of the original PC Speaker driver is partially formalised in Coq. Furthermore, some relevant formal properties of the formalised functionality are discussed. Subsequently, a kernel module is defined, utilising the modified variants of CertiCoq and VeriFFI to compile a working device driver. It is furthermore shown that it is possible to compile the synthesised code with CompCert, thereby extending the guarantee of correctness to the assembly layer. This is followed by a performance evaluation that compares a naive formalisation of the PC speaker functionality with the original PC Speaker driver pointing out the weaknesses in the formalisation and possible improvements. The part closes with a summary of the results, their implications and open questions being raised. The last part lists all used sources, separated into scientific literature, documentations or reference manuals and artifacts, i.e. source code.}, language = {en} } @article{AguadoCabalarFandinoetal.2019, author = {Aguado, Felicidad and Cabalar, Pedro and Fandi{\~n}o, Jorge and Pearce, David and Perez, Gilberto and Vidal, Concepcion}, title = {Forgetting auxiliary atoms in forks}, series = {Artificial intelligence}, volume = {275}, journal = {Artificial intelligence}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0004-3702}, doi = {10.1016/j.artint.2019.07.005}, pages = {575 -- 601}, year = {2019}, abstract = {In this work we tackle the problem of checking strong equivalence of logic programs that may contain local auxiliary atoms, to be removed from their stable models and to be forbidden in any external context. We call this property projective strong equivalence (PSE). It has been recently proved that not any logic program containing auxiliary atoms can be reformulated, under PSE, as another logic program or formula without them - this is known as strongly persistent forgetting. In this paper, we introduce a conservative extension of Equilibrium Logic and its monotonic basis, the logic of Here-and-There, in which we deal with a new connective '|' we call fork. We provide a semantic characterisation of PSE for forks and use it to show that, in this extension, it is always possible to forget auxiliary atoms under strong persistence. We further define when the obtained fork is representable as a regular formula.}, language = {en} } @article{AguadoCabalarFandinoetal.2019, author = {Aguado, Felicidad and Cabalar, Pedro and Fandi{\~n}o, Jorge and Pearce, David and Perez, Gilberto and Vidal-Peracho, Concepcion}, title = {Revisiting Explicit Negation in Answer Set Programming}, series = {Theory and practice of logic programming}, volume = {19}, journal = {Theory and practice of logic programming}, number = {5-6}, publisher = {Cambridge Univ. Press}, address = {New York}, issn = {1471-0684}, doi = {10.1017/S1471068419000267}, pages = {908 -- 924}, year = {2019}, language = {en} } @misc{Ziemann2024, type = {Master Thesis}, author = {Ziemann, Felix}, title = {Entwicklung und Evaluation einer prototypischen Lernumgebung f{\"u}r das systematische Debugging logischer Fehler in Quellcode}, doi = {10.25932/publishup-63273}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-632734}, school = {Universit{\"a}t Potsdam}, pages = {x, 98}, year = {2024}, abstract = {Wo programmiert wird, da passieren Fehler. Um das Debugging, also die Suche sowie die Behebung von Fehlern in Quellcode, st{\"a}rker explizit zu adressieren, verfolgt die vorliegende Arbeit das Ziel, entlang einer prototypischen Lernumgebung sowohl ein systematisches Vorgehen w{\"a}hrend des Debuggings zu vermitteln als auch Gestaltungsfolgerungen f{\"u}r ebensolche Lernumgebungen zu identifizieren. Dazu wird die folgende Forschungsfrage gestellt: Wie verhalten sich die Lernenden w{\"a}hrend des kurzzeitigen Gebrauchs einer Lernumgebung nach dem Cognitive Apprenticeship-Ansatz mit dem Ziel der expliziten Vermittlung eines systematischen Debuggingvorgehens und welche Eindr{\"u}cke entstehen w{\"a}hrend der Bearbeitung? Zur Beantwortung dieser Forschungsfrage wurde orientierend an literaturbasierten Implikationen f{\"u}r die Vermittlung von Debugging und (medien-)didaktischen Gestaltungsaspekten eine prototypische Lernumgebung entwickelt und im Rahmen einer qualitativen Nutzerstudie mit Bachelorstudierenden informatischer Studieng{\"a}nge erprobt. Hierbei wurden zum einen anwendungsbezogene Verbesserungspotenziale identifiziert. Zum anderen zeigte sich insbesondere gegen{\"u}ber der Systematisierung des Debuggingprozesses innerhalb der Aufgabenbearbeitung eine positive Resonanz. Eine Untersuchung, inwieweit sich die Nutzung der Lernumgebung l{\"a}ngerfristig auf das Verhalten von Personen und ihre Vorgehensweisen w{\"a}hrend des Debuggings auswirkt, k{\"o}nnte Gegenstand kommender Arbeiten sein.}, language = {de} } @article{SchickBojahrHerzogetal.2014, author = {Schick, Daniel and Bojahr, Andre and Herzog, Marc and Shayduk, Roman and von Korff Schmising, Clemens and Bargheer, Matias}, title = {Udkm1Dsim-A simulation toolkit for 1D ultrafast dynamics in condensed matter}, series = {Computer physics communications : an international journal devoted to computational physics and computer programs in physics}, volume = {185}, journal = {Computer physics communications : an international journal devoted to computational physics and computer programs in physics}, number = {2}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0010-4655}, doi = {10.1016/j.cpc.2013.10.009}, pages = {651 -- 660}, year = {2014}, abstract = {The UDKM1DSIM toolbox is a collection of MATLAB (MathWorks Inc.) classes and routines to simulate the structural dynamics and the according X-ray diffraction response in one-dimensional crystalline sample structures upon an arbitrary time-dependent external stimulus, e.g. an ultrashort laser pulse. The toolbox provides the capabilities to define arbitrary layered structures on the atomic level including a rich database of corresponding element-specific physical properties. The excitation of ultrafast dynamics is represented by an N-temperature model which is commonly applied for ultrafast optical excitations. Structural dynamics due to thermal stress are calculated by a linear-chain model of masses and springs. The resulting X-ray diffraction response is computed by dynamical X-ray theory. The UDKM1DSIM toolbox is highly modular and allows for introducing user-defined results at any step in the simulation procedure. Program summary Program title: udkm1Dsim Catalogue identifier: AERH_v1_0 Program summary URL: http://cpc.cs.qub.ac.uk/summaries/AERH_v1_0.html Licensing provisions: BSD No. of lines in distributed program, including test data, etc.: 130221 No. of bytes in distributed program, including test data, etc.: 2746036 Distribution format: tar.gz Programming language: Matlab (MathWorks Inc.). Computer: PC/Workstation. Operating system: Running Matlab installation required (tested on MS Win XP -7, Ubuntu Linux 11.04-13.04). Has the code been vectorized or parallelized?: Parallelization for dynamical XRD computations. Number of processors used: 1-12 for Matlab Parallel Computing Toolbox; 1 - infinity for Matlab Distributed Computing Toolbox External routines: Optional: Matlab Parallel Computing Toolbox, Matlab Distributed Computing Toolbox Required (included in the package): mtimesx Fast Matrix Multiply for Matlab by James Tursa, xml io tools by Jaroslaw Tuszynski, textprogressbar by Paul Proteus Nature of problem: Simulate the lattice dynamics of 1D crystalline sample structures due to an ultrafast excitation including thermal transport and compute the corresponding transient X-ray diffraction pattern. Solution method: Restrictions: The program is restricted to 1D sample structures and is further limited to longitudinal acoustic phonon modes and symmetrical X-ray diffraction geometries. Unusual features: The program is highly modular and allows the inclusion of user-defined inputs at any time of the simulation procedure. Running time: The running time is highly dependent on the number of unit cells in the sample structure and other simulation parameters such as time span or angular grid for X-ray diffraction computations. However, the example files are computed in approx. 1-5 min each on a 8 Core Processor with 16 GB RAM available.}, language = {en} } @phdthesis{Videla2014, author = {Videla, Santiago}, title = {Reasoning on the response of logical signaling networks with answer set programming}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-71890}, school = {Universit{\"a}t Potsdam}, year = {2014}, abstract = {Deciphering the functioning of biological networks is one of the central tasks in systems biology. In particular, signal transduction networks are crucial for the understanding of the cellular response to external and internal perturbations. Importantly, in order to cope with the complexity of these networks, mathematical and computational modeling is required. We propose a computational modeling framework in order to achieve more robust discoveries in the context of logical signaling networks. More precisely, we focus on modeling the response of logical signaling networks by means of automated reasoning using Answer Set Programming (ASP). ASP provides a declarative language for modeling various knowledge representation and reasoning problems. Moreover, available ASP solvers provide several reasoning modes for assessing the multitude of answer sets. Therefore, leveraging its rich modeling language and its highly efficient solving capacities, we use ASP to address three challenging problems in the context of logical signaling networks: learning of (Boolean) logical networks, experimental design, and identification of intervention strategies. Overall, the contribution of this thesis is three-fold. Firstly, we introduce a mathematical framework for characterizing and reasoning on the response of logical signaling networks. Secondly, we contribute to a growing list of successful applications of ASP in systems biology. Thirdly, we present a software providing a complete pipeline for automated reasoning on the response of logical signaling networks.}, language = {en} } @article{DimopoulosGebserLuehneetal.2019, author = {Dimopoulos, Yannis and Gebser, Martin and L{\"u}hne, Patrick and Romero Davila, Javier and Schaub, Torsten}, title = {plasp 3}, series = {Theory and practice of logic programming}, volume = {19}, journal = {Theory and practice of logic programming}, number = {3}, publisher = {Cambridge Univ. Press}, address = {New York}, issn = {1471-0684}, doi = {10.1017/S1471068418000583}, pages = {477 -- 504}, year = {2019}, abstract = {We describe the new version of the Planning Domain Definition Language (PDDL)-to-Answer Set Programming (ASP) translator plasp. First, it widens the range of accepted PDDL features. Second, it contains novel planning encodings, some inspired by Satisfiability Testing (SAT) planning and others exploiting ASP features such as well-foundedness. All of them are designed for handling multivalued fluents in order to capture both PDDL as well as SAS planning formats. Third, enabled by multishot ASP solving, it offers advanced planning algorithms also borrowed from SAT planning. As a result, plasp provides us with an ASP-based framework for studying a variety of planning techniques in a uniform setting. Finally, we demonstrate in an empirical analysis that these techniques have a significant impact on the performance of ASP planning.}, language = {en} } @article{KaminskiSchaubSiegeletal.2013, author = {Kaminski, Roland and Schaub, Torsten and Siegel, Anne and Videla, Santiago}, title = {Minimal intervention strategies in logical signaling networks with ASP}, series = {Theory and practice of logic programming}, volume = {13}, journal = {Theory and practice of logic programming}, publisher = {Cambridge Univ. Press}, address = {New York}, issn = {1471-0684}, doi = {10.1017/S1471068413000422}, pages = {675 -- 690}, year = {2013}, abstract = {Proposing relevant perturbations to biological signaling networks is central to many problems in biology and medicine because it allows for enabling or disabling certain biological outcomes. In contrast to quantitative methods that permit fine-grained (kinetic) analysis, qualitative approaches allow for addressing large-scale networks. This is accomplished by more abstract representations such as logical networks. We elaborate upon such a qualitative approach aiming at the computation of minimal interventions in logical signaling networks relying on Kleene's three-valued logic and fixpoint semantics. We address this problem within answer set programming and show that it greatly outperforms previous work using dedicated algorithms.}, language = {en} } @article{SchaubBrueningNicolas1996, author = {Schaub, Torsten and Br{\"u}ning, Stefan and Nicolas, Pascal}, title = {XRay : a prolog technology theorem prover for default reasoning: a system description}, isbn = {3-540-61511-3}, year = {1996}, language = {en} } @article{BesnardSchaub1996, author = {Besnard, Philippe and Schaub, Torsten}, title = {A simple signed system for paraconsistent reasoning}, isbn = {3-540-61630-6}, year = {1996}, language = {en} } @article{GebserSchaubTompitsetal.2007, author = {Gebser, Martin and Schaub, Torsten and Tompits, Hans and Woltran, Stefan}, title = {Alternative characterizations for program equivalence under aswer-set semantics : a preliminary report}, year = {2007}, language = {en} } @phdthesis{Konczak2007, author = {Konczak, Kathrin}, title = {Preferences in answer set programming}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus-12058}, school = {Universit{\"a}t Potsdam}, year = {2007}, abstract = {Answer Set Programming (ASP) emerged in the late 1990s as a new logic programming paradigm, having its roots in nonmonotonic reasoning, deductive databases, and logic programming with negation as failure. The basic idea of ASP is to represent a computational problem as a logic program whose answer sets correspond to solutions, and then to use an answer set solver for finding answer sets of the program. ASP is particularly suited for solving NP-complete search problems. Among these, we find applications to product configuration, diagnosis, and graph-theoretical problems, e.g. finding Hamiltonian cycles. On different lines of ASP research, many extensions of the basic formalism have been proposed. The most intensively studied one is the modelling of preferences in ASP. They constitute a natural and effective way of selecting preferred solutions among a plethora of solutions for a problem. For example, preferences have been successfully used for timetabling, auctioning, and product configuration. In this thesis, we concentrate on preferences within answer set programming. Among several formalisms and semantics for preference handling in ASP, we concentrate on ordered logic programs with the underlying D-, W-, and B-semantics. In this setting, preferences are defined among rules of a logic program. They select preferred answer sets among (standard) answer sets of the underlying logic program. Up to now, those preferred answer sets have been computed either via a compilation method or by meta-interpretation. Hence, the question comes up, whether and how preferences can be integrated into an existing ASP solver. To solve this question, we develop an operational graph-based framework for the computation of answer sets of logic programs. Then, we integrate preferences into this operational approach. We empirically observe that our integrative approach performs in most cases better than the compilation method or meta-interpretation. Another research issue in ASP are optimization methods that remove redundancies, as also found in database query optimizers. For these purposes, the rather recently suggested notion of strong equivalence for ASP can be used. If a program is strongly equivalent to a subprogram of itself, then one can always use the subprogram instead of the original program, a technique which serves as an effective optimization method. Up to now, strong equivalence has not been considered for logic programs with preferences. In this thesis, we tackle this issue and generalize the notion of strong equivalence to ordered logic programs. We give necessary and sufficient conditions for the strong equivalence of two ordered logic programs. Furthermore, we provide program transformations for ordered logic programs and show in how far preferences can be simplified. Finally, we present two new applications for preferences within answer set programming. First, we define new procedures for group decision making, which we apply to the problem of scheduling a group meeting. As a second new application, we reconstruct a linguistic problem appearing in German dialects within ASP. Regarding linguistic studies, there is an ongoing debate about how unique the rule systems of language are in human cognition. The reconstruction of grammatical regularities with tools from computer science has consequences for this debate: if grammars can be modelled this way, then they share core properties with other non-linguistic rule systems.}, language = {en} } @article{GebserObermeierSchaubetal.2018, author = {Gebser, Martin and Obermeier, Philipp and Schaub, Torsten and Ratsch-Heitmann, Michel and Runge, Mario}, title = {Routing driverless transport vehicles in car assembly with answer set programming}, series = {Theory and practice of logic programming}, volume = {18}, journal = {Theory and practice of logic programming}, number = {3-4}, publisher = {Cambridge Univ. Press}, address = {New York}, issn = {1471-0684}, doi = {10.1017/S1471068418000182}, pages = {520 -- 534}, year = {2018}, abstract = {Automated storage and retrieval systems are principal components of modern production and warehouse facilities. In particular, automated guided vehicles nowadays substitute human-operated pallet trucks in transporting production materials between storage locations and assembly stations. While low-level control systems take care of navigating such driverless vehicles along programmed routes and avoid collisions even under unforeseen circumstances, in the common case of multiple vehicles sharing the same operation area, the problem remains how to set up routes such that a collection of transport tasks is accomplished most effectively. We address this prevalent problem in the context of car assembly at Mercedes-Benz Ludwigsfelde GmbH, a large-scale producer of commercial vehicles, where routes for automated guided vehicles used in the production process have traditionally been hand-coded by human engineers. Such adhoc methods may suffice as long as a running production process remains in place, while any change in the factory layout or production targets necessitates tedious manual reconfiguration, not to mention the missing portability between different production plants. Unlike this, we propose a declarative approach based on Answer Set Programming to optimize the routes taken by automated guided vehicles for accomplishing transport tasks. The advantages include a transparent and executable problem formalization, provable optimality of routes relative to objective criteria, as well as elaboration tolerance towards particular factory layouts and production targets. Moreover, we demonstrate that our approach is efficient enough to deal with the transport tasks evolving in realistic production processes at the car factory of Mercedes-Benz Ludwigsfelde GmbH.}, language = {en} } @article{LindauerHoosLeytonBrownetal.2017, author = {Lindauer, Marius and Hoos, Holger and Leyton-Brown, Kevin and Schaub, Torsten}, title = {Automatic construction of parallel portfolios via algorithm configuration}, series = {Artificial intelligence}, volume = {244}, journal = {Artificial intelligence}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0004-3702}, doi = {10.1016/j.artint.2016.05.004}, pages = {272 -- 290}, year = {2017}, abstract = {Since 2004, increases in computational power described by Moore's law have substantially been realized in the form of additional cores rather than through faster clock speeds. To make effective use of modern hardware when solving hard computational problems, it is therefore necessary to employ parallel solution strategies. In this work, we demonstrate how effective parallel solvers for propositional satisfiability (SAT), one of the most widely studied NP-complete problems, can be produced automatically from any existing sequential, highly parametric SAT solver. Our Automatic Construction of Parallel Portfolios (ACPP) approach uses an automatic algorithm configuration procedure to identify a set of configurations that perform well when executed in parallel. Applied to two prominent SAT solvers, Lingeling and clasp, our ACPP procedure identified 8-core solvers that significantly outperformed their sequential counterparts on a diverse set of instances from the application and hard combinatorial category of the 2012 SAT Challenge. We further extended our ACPP approach to produce parallel portfolio solvers consisting of several different solvers by combining their configuration spaces. Applied to the component solvers of the 2012 SAT Challenge gold medal winning SAT Solver pfolioUZK, our ACPP procedures produced a significantly better-performing parallel SAT solver.}, language = {en} } @article{GebserKaufmannSchaub2012, author = {Gebser, Martin and Kaufmann, Benjamin and Schaub, Torsten}, title = {Conflict-driven answer set solving: From theory to practice}, series = {Artificial intelligence}, volume = {187}, journal = {Artificial intelligence}, number = {8}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0004-3702}, doi = {10.1016/j.artint.2012.04.001}, pages = {52 -- 89}, year = {2012}, abstract = {We introduce an approach to computing answer sets of logic programs, based on concepts successfully applied in Satisfiability (SAT) checking. The idea is to view inferences in Answer Set Programming (ASP) as unit propagation on nogoods. This provides us with a uniform constraint-based framework capturing diverse inferences encountered in ASP solving. Moreover, our approach allows us to apply advanced solving techniques from the area of SAT. As a result, we present the first full-fledged algorithmic framework for native conflict-driven ASP solving. Our approach is implemented in the ASP solver clasp that has demonstrated its competitiveness and versatility by winning first places at various solver contests.}, language = {en} } @article{BesnardSchaubTompitsetal.2002, author = {Besnard, Philippe and Schaub, Torsten and Tompits, Hans and Woltran, Stefan}, title = {Paraconsistent reasoning via quantified boolean formulas}, isbn = {3-540-44190-5}, year = {2002}, language = {en} } @article{GebserKaufmannNeumannetal.2007, author = {Gebser, Martin and Kaufmann, Benjamin and Neumann, Andr{\´e} and Schaub, Torsten}, title = {Clasp : a conflict-driven answer set solver}, isbn = {978-3-540- 72199-4}, year = {2007}, language = {en} } @article{BrainFaberMarateaetal.2007, author = {Brain, Martin and Faber, Wolfgang and Maratea, Marco and Polleres, Axel and Schaub, Torsten and Schindlauer, Roman}, title = {What should an ASP solver output? : a multiple position paper}, year = {2007}, language = {en} } @article{ThielscherSchaub1995, author = {Thielscher, Michael and Schaub, Torsten}, title = {Default reasoning by deductive planning}, year = {1995}, language = {en} } @article{BanbaraSohTamuraetal.2013, author = {Banbara, Mutsunori and Soh, Takehide and Tamura, Naoyuki and Inoue, Katsumi and Schaub, Torsten}, title = {Answer set programming as a modeling language for course timetabling}, series = {Theory and practice of logic programming}, volume = {13}, journal = {Theory and practice of logic programming}, number = {2}, publisher = {Cambridge Univ. Press}, address = {New York}, issn = {1471-0684}, doi = {10.1017/S1471068413000495}, pages = {783 -- 798}, year = {2013}, abstract = {The course timetabling problem can be generally defined as the task of assigning a number of lectures to a limited set of timeslots and rooms, subject to a given set of hard and soft constraints. The modeling language for course timetabling is required to be expressive enough to specify a wide variety of soft constraints and objective functions. Furthermore, the resulting encoding is required to be extensible for capturing new constraints and for switching them between hard and soft, and to be flexible enough to deal with different formulations. In this paper, we propose to make effective use of ASP as a modeling language for course timetabling. We show that our ASP-based approach can naturally satisfy the above requirements, through an ASP encoding of the curriculum-based course timetabling problem proposed in the third track of the second international timetabling competition (ITC-2007). Our encoding is compact and human-readable, since each constraint is individually expressed by either one or two rules. Each hard constraint is expressed by using integrity constraints and aggregates of ASP. Each soft constraint S is expressed by rules in which the head is the form of penalty (S, V, C), and a violation V and its penalty cost C are detected and calculated respectively in the body. We carried out experiments on four different benchmark sets with five different formulations. We succeeded either in improving the bounds or producing the same bounds for many combinations of problem instances and formulations, compared with the previous best known bounds.}, language = {en} } @article{GebserSabuncuSchaub2011, author = {Gebser, Martin and Sabuncu, Orkunt and Schaub, Torsten}, title = {An incremental answer set programming based system for finite model computation}, series = {AI communications : AICOM ; the European journal on artificial intelligence}, volume = {24}, journal = {AI communications : AICOM ; the European journal on artificial intelligence}, number = {2}, publisher = {IOS Press}, address = {Amsterdam}, issn = {0921-7126}, doi = {10.3233/AIC-2011-0496}, pages = {195 -- 212}, year = {2011}, abstract = {We address the problem of Finite Model Computation (FMC) of first-order theories and show that FMC can efficiently and transparently be solved by taking advantage of a recent extension of Answer Set Programming (ASP), called incremental Answer Set Programming (iASP). The idea is to use the incremental parameter in iASP programs to account for the domain size of a model. The FMC problem is then successively addressed for increasing domain sizes until an answer set, representing a finite model of the original first-order theory, is found. We implemented a system based on the iASP solver iClingo and demonstrate its competitiveness by showing that it slightly outperforms the winner of the FNT division of CADE's 2009 Automated Theorem Proving (ATP) competition on the respective benchmark collection.}, language = {en} } @misc{LifschitzSchaubWoltran2018, author = {Lifschitz, Vladimir and Schaub, Torsten and Woltran, Stefan}, title = {Interview with Vladimir Lifschitz}, series = {K{\"u}nstliche Intelligenz}, volume = {32}, journal = {K{\"u}nstliche Intelligenz}, number = {2-3}, publisher = {Springer}, address = {Heidelberg}, issn = {0933-1875}, doi = {10.1007/s13218-018-0552-x}, pages = {213 -- 218}, year = {2018}, abstract = {This interview with Vladimir Lifschitz was conducted by Torsten Schaub at the University of Texas at Austin in August 2017. The question set was compiled by Torsten Schaub and Stefan Woltran.}, language = {en} } @article{DelgrandeSchaubTompits2006, author = {Delgrande, James Patrick and Schaub, Torsten and Tompits, Hans}, title = {A Preference-Based Framework for Updating logic Programs : preliminary reports}, year = {2006}, language = {en} } @article{LinkeSchaub1998, author = {Linke, Thomas and Schaub, Torsten}, title = {An approach to query-answering in Reiter's default logic and the underlying existence of extensions problem.}, isbn = {3-540-65141-1}, year = {1998}, language = {en} } @article{RoessnerLuedemannBrustetal.2001, author = {Roessner, Ute and Luedemann, A. and Brust, D. and Fiehn, Oliver and Linke, Thomas and Willmitzer, Lothar and Fernie, Alisdair}, title = {Metabolic profiling allows comprehensive phenotyping of genetically or environmentally modified plant systems}, issn = {1040-4651}, year = {2001}, language = {en} } @article{BanbaraInoueKaufmannetal.2018, author = {Banbara, Mutsunori and Inoue, Katsumi and Kaufmann, Benjamin and Okimoto, Tenda and Schaub, Torsten and Soh, Takehide and Tamura, Naoyuki and Wanko, Philipp}, title = {teaspoon}, series = {Annals of operation research}, volume = {275}, journal = {Annals of operation research}, number = {1}, publisher = {Springer}, address = {Dordrecht}, issn = {0254-5330}, doi = {10.1007/s10479-018-2757-7}, pages = {3 -- 37}, year = {2018}, abstract = {Answer Set Programming (ASP) is an approach to declarative problem solving, combining a rich yet simple modeling language with high performance solving capacities. We here develop an ASP-based approach to curriculum-based course timetabling (CB-CTT), one of the most widely studied course timetabling problems. The resulting teaspoon system reads a CB-CTT instance of a standard input format and converts it into a set of ASP facts. In turn, these facts are combined with a first-order encoding for CB-CTT solving, which can subsequently be solved by any off-the-shelf ASP systems. We establish the competitiveness of our approach by empirically contrasting it to the best known bounds obtained so far via dedicated implementations. Furthermore, we extend the teaspoon system to multi-objective course timetabling and consider minimal perturbation problems.}, language = {en} } @article{FriouxSchaubSchellhornetal.2019, author = {Frioux, Cl{\´e}mence and Schaub, Torsten and Schellhorn, Sebastian and Siegel, Anne and Wanko, Philipp}, title = {Hybrid metabolic network completion}, series = {Theory and practice of logic programming}, volume = {19}, journal = {Theory and practice of logic programming}, number = {1}, publisher = {Cambridge University Press}, address = {New York}, issn = {1471-0684}, doi = {10.1017/S1471068418000455}, pages = {83 -- 108}, year = {2019}, abstract = {Metabolic networks play a crucial role in biology since they capture all chemical reactions in an organism. While there are networks of high quality for many model organisms, networks for less studied organisms are often of poor quality and suffer from incompleteness. To this end, we introduced in previous work an answer set programming (ASP)-based approach to metabolic network completion. Although this qualitative approach allows for restoring moderately degraded networks, it fails to restore highly degraded ones. This is because it ignores quantitative constraints capturing reaction rates. To address this problem, we propose a hybrid approach to metabolic network completion that integrates our qualitative ASP approach with quantitative means for capturing reaction rates. We begin by formally reconciling existing stoichiometric and topological approaches to network completion in a unified formalism. With it, we develop a hybrid ASP encoding and rely upon the theory reasoning capacities of the ASP system dingo for solving the resulting logic program with linear constraints over reals. We empirically evaluate our approach by means of the metabolic network of Escherichia coli. Our analysis shows that our novel approach yields greatly superior results than obtainable from purely qualitative or quantitative approaches.}, language = {en} } @misc{NeubauerHaubeltWankoetal.2018, author = {Neubauer, Kai and Haubelt, Christian and Wanko, Philipp and Schaub, Torsten}, title = {Utilizing quad-trees for efficient design space exploration with partial assignment evaluation}, series = {2018 23rd Asia and South Pacific Design Automation Conference (ASP-DAC)}, journal = {2018 23rd Asia and South Pacific Design Automation Conference (ASP-DAC)}, publisher = {IEEE}, address = {New York}, isbn = {978-1-5090-0602-1}, issn = {2153-6961}, doi = {10.1109/ASPDAC.2018.8297362}, pages = {434 -- 439}, year = {2018}, abstract = {Recently, it has been shown that constraint-based symbolic solving techniques offer an efficient way for deciding binding and routing options in order to obtain a feasible system level implementation. In combination with various background theories, a feasibility analysis of the resulting system may already be performed on partial solutions. That is, infeasible subsets of mapping and routing options can be pruned early in the decision process, which fastens the solving accordingly. However, allowing a proper design space exploration including multi-objective optimization also requires an efficient structure for storing and managing non-dominated solutions. In this work, we propose and study the usage of the Quad-Tree data structure in the context of partial assignment evaluation during system synthesis. Out experiments show that unnecessary dominance checks can be avoided, which indicates a preference of Quad-Trees over a commonly used list-based implementation for large combinatorial optimization problems.}, language = {en} } @article{GebserKaminskiKaufmannetal.2018, author = {Gebser, Martin and Kaminski, Roland and Kaufmann, Benjamin and L{\"u}hne, Patrick and Obermeier, Philipp and Ostrowski, Max and Romero Davila, Javier and Schaub, Torsten and Schellhorn, Sebastian and Wanko, Philipp}, title = {The Potsdam Answer Set Solving Collection 5.0}, series = {K{\"u}nstliche Intelligenz}, volume = {32}, journal = {K{\"u}nstliche Intelligenz}, number = {2-3}, publisher = {Springer}, address = {Heidelberg}, issn = {0933-1875}, doi = {10.1007/s13218-018-0528-x}, pages = {181 -- 182}, year = {2018}, abstract = {The Potsdam answer set solving collection, or Potassco for short, bundles various tools implementing and/or applying answer set programming. The article at hand succeeds an earlier description of the Potassco project published in Gebser et al. (AI Commun 24(2):107-124, 2011). Hence, we concentrate in what follows on the major features of the most recent, fifth generation of the ASP system clingo and highlight some recent resulting application systems.}, language = {en} } @article{HaubeltNeubauerSchaubetal.2018, author = {Haubelt, Christian and Neubauer, Kai and Schaub, Torsten and Wanko, Philipp}, title = {Design space exploration with answer set programming}, series = {K{\"u}nstliche Intelligenz}, volume = {32}, journal = {K{\"u}nstliche Intelligenz}, number = {2-3}, publisher = {Springer}, address = {Heidelberg}, issn = {0933-1875}, doi = {10.1007/s13218-018-0530-3}, pages = {205 -- 206}, year = {2018}, abstract = {The aim of our project design space exploration with answer set programming is to develop a general framework based on Answer Set Programming (ASP) that finds valid solutions to the system design problem and simultaneously performs Design Space Exploration (DSE) to find the most favorable alternatives. We leverage recent developments in ASP solving that allow for tight integration of background theories to create a holistic framework for effective DSE.}, language = {en} }