4,956 research outputs found
Satisfiability Games for Branching-Time Logics
The satisfiability problem for branching-time temporal logics like CTL*, CTL
and CTL+ has important applications in program specification and verification.
Their computational complexities are known: CTL* and CTL+ are complete for
doubly exponential time, CTL is complete for single exponential time. Some
decision procedures for these logics are known; they use tree automata,
tableaux or axiom systems. In this paper we present a uniform game-theoretic
framework for the satisfiability problem of these branching-time temporal
logics. We define satisfiability games for the full branching-time temporal
logic CTL* using a high-level definition of winning condition that captures the
essence of well-foundedness of least fixpoint unfoldings. These winning
conditions form formal languages of \omega-words. We analyse which kinds of
deterministic {\omega}-automata are needed in which case in order to recognise
these languages. We then obtain a reduction to the problem of solving parity or
B\"uchi games. The worst-case complexity of the obtained algorithms matches the
known lower bounds for these logics. This approach provides a uniform, yet
complexity-theoretically optimal treatment of satisfiability for branching-time
temporal logics. It separates the use of temporal logic machinery from the use
of automata thus preserving a syntactical relationship between the input
formula and the object that represents satisfiability, i.e. a winning strategy
in a parity or B\"uchi game. The games presented here work on a Fischer-Ladner
closure of the input formula only. Last but not least, the games presented here
come with an attempt at providing tool support for the satisfiability problem
of complex branching-time logics like CTL* and CTL+
LoLa: a modular ontology of logics, languages and translations
The Distributed Ontology Language (DOL), currently being standardised within the OntoIOp (Ontology Integration and Interoperability) activity of ISO/TC 37/SC 3, aims at providing a unified framework for (i) ontologies formalised in heterogeneous logics, (ii) modular ontologies, (iii) links between ontologies, and (iv) annotation of ontologies.\ud
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This paper focuses on the LoLa ontology, which formally describes DOL's vocabulary for logics, ontology languages (and their serialisations), as well as logic translations. Interestingly, to adequately formalise the logical relationships between these notions, LoLa itself needs to be axiomatised heterogeneously---a task for which we choose DOL. Namely, we use the logic RDF for ABox assertions, OWL for basic axiomatisations of various modules concerning logics, languages, and translations, FOL for capturing certain closure rules that are not expressible in OWL (For the sake of tool availability it is still helpful not to map everything to FOL.), and circumscription for minimising the extension of concepts describing default translations
Integrating watershed-scale and river-reach protection and restoration planning to promote climate resilience in the South Fork Nooksack River (SFNR)
The Nooksack Indian Tribe reservation is located at the foot of the North Cascades Mountains, approximately 13 miles east of Bellingham, WA and the Salish Sea. The Tribe relies on a harvestable surplus of Pacific salmon in the Nooksack River for cultural, subsistence, and commercial purposes. Today, Pacific salmon runs are less than 10 percent of the runs in the late 1800’s. Causes of the declines are complex; however, it is well understood that the legacy of commercial forestry, agriculture, and development has increased sediment loading and water temperature. Climate impacts will cumulatively add to the legacy impacts, which are still evident today. The Tribe has been an effective member of a collaboration of agencies, tribes, universities, contractors, and NGOs aimed at addressing both current and projected impacts on water quality and streamflow. Whereas many restoration and planning efforts focus exclusively on either the stream corridor or adjacent upland land use when considering water quality, the Tribe has successfully integrated watershed-scale planning with reach-scale planning to more fully address the needs of fish in the South Fork Nooksack River. In particular, the tribe initiated a federally-funded comprehensive watershed conservation planning effort. The watershed-scale approach includes assessment of upland land use impacts and adaptation strategies to ameliorate downstream water quality issues. The results are driving the development of silvicultural and in-stream strategies to restore natural water storage functions. Concurrently, the Tribe received NEP grant funding as administered by WA Department of Ecology to develop a reach-scale protection and restoration plan for the SFNR. The reach-scale approach involves engaging riparian landowners to determine interest in protecting and restoring buffers along the SFNR and tributaries, and developing implementation plans for such action. Together, these efforts provide a case study in identifying in-stream, riparian, and upland protection and restoration strategies to support fish survival
The Distributed Ontology Language (DOL): Use Cases, Syntax, and Extensibility
The Distributed Ontology Language (DOL) is currently being standardized
within the OntoIOp (Ontology Integration and Interoperability) activity of
ISO/TC 37/SC 3. It aims at providing a unified framework for (1) ontologies
formalized in heterogeneous logics, (2) modular ontologies, (3) links between
ontologies, and (4) annotation of ontologies. This paper presents the current
state of DOL's standardization. It focuses on use cases where distributed
ontologies enable interoperability and reusability. We demonstrate relevant
features of the DOL syntax and semantics and explain how these integrate into
existing knowledge engineering environments.Comment: Terminology and Knowledge Engineering Conference (TKE) 2012-06-20 to
2012-06-21 Madrid, Spai
High-accuracy peak picking of proteomics data
A new peak picking algorithm for the analysis of mass spectrometric (MS) data is presented.
It is independent of the underlying machine or ionization method, and is able to resolve highly
convoluted and asymmetric signals. The method uses the multiscale nature of spectrometric data by first detecting
the mass peaks in the wavelet-transformed signal before a given asymmetric peak function is fitted to the raw data.
In an optional third stage, the resulting fit can be further improved using techniques from nonlinear optimization.
In contrast to currently established techniques (e.g. SNAP, Apex) our algorithm is able to separate overlapping peaks
of multiply charged peptides in ESI-MS data of low resolution.
Its improved accuracy with respect to peak positions makes it a valuable preprocessing method for MS-based identification
and quantification experiments. The method has been validated on a number of different annotated test cases,
where it compares favorably in both runtime and accuracy with currently established techniques.
An implementation of the algorithm is freely available in our open source framework OpenMS (www.open-ms.de)
B-Meson Distribution Amplitudes of Geometric Twist vs. Dynamical Twist
Two- and three-particle distribution amplitudes of heavy pseudoscalar mesons
of well-defined geometric twist are introduced. They are obtained from
appropriately parametrized vacuum-to-meson matrix elements by applying those
twist projectors which determine the enclosed light-cone operators of definite
geometric twist and, in addition, observing the heavy quark constraint.
Comparing these distribution amplitudes with the conventional ones of dynamical
twist we derive relations between them, partially being of Wandzura-Wilczek
type; also sum rules of Burkhardt-Cottingham type are derived.The derivation is
performed for the (double) Mellin moments and then re-summed to the non-local
distribution amplitudes. Furthermore, a parametrization of vacuum-to-meson
matrix elements for non-local operators off the light-cone in terms of
distribution amplitudes accompanying independent kinematical structures is
derived.Comment: 18 pages, Latex 2e, no figure
Circadian rhythms in obsessive-compulsive disorder
The etiopathology and neurobiology of obsessive-compulsive disorder (OCD) are not fully understood. As for altered circadian rhythms associated with OCD, hormonal dysregulation and a delayed sleep phase have come into the focus of research. The novel antidepressant agomelatine is able to resynchronize circadian rhythms and the augmentative administration of this compound has been shown to be of benefit in some OCD patients who are refractory to common forms of pharmacotherapy. Adjunctive chronotherapy might also enhance the outcome in treatment-refractory OCD. The present review summarises the findings regarding circadian abnormalities in OCD
MRT-Bildverarbeitung durch intelligente Mustererkennungsalgorithmen: Zeitreihenanalyse durch selbstorganisierende Clustersegmentierung
Magnetresonanztomographie ist ein wichtiges nichtinvasives, bildgebendes Schnittbildverfahren in der medizinischen Diagnostik. Neben der klassischen Aufgabe der Strukturbildgebung sind in den letzten Jahren auch neue Anwendungsfelder der Funktionsbildgebung in den Brennpunkt des medizinisch-wissenschaftlichen Interesses gerückt. Die vorliegende Arbeit untersucht die Anwendung explorativer Methoden zur Datenanalyse der zeitlichen Dynamik in funktionellen MRT-Zeitreihen durch Methoden der Clusteranalyse sowie durch Komponentenanalyseverfahren (PCA, ICA) unter besonderer Berücksichtigung der Aspekte Rechenzeit, Objektivität, Reliabilität sowie Validität der Partitionierungsergebnisse.
Darüber hinaus wird der Ansatz der Clusteranalyse zur Anwendung auf weitere dynamische MRT-Zeitreihen erweitert: zur Clusteranalyse dynamischer perfusionsgewichteter MRT-Bildfolgen, zur Clusteranalyse Kontrastmittel-unterstützter dynamischer MRT-Mammographie-Bildfolgen sowie zur Konnektivitätsanalyse im motorischen System des Menschen
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