14 research outputs found

    Note on the succinctness of deterministic, nondeterministic, probabilistic and quantum finite automata

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    We investigate the succinctness of several kinds of unary automata by studying their state complexity in accepting the family {Lm} of cyclic languages, where Lm = {akm|k 08 N}. In particular, we show that, for any m, the number of states necessary and sufficient for accepting the unary language Lm with isolated cut point on one-way probabilistic finite automata is p1\u3b11 + p2\u3b12 + ef + ps\u3b1s, with p1\u3b11p2\u3b12 ef ps\u3b1s being the factorization of m. To prove this result, we give a general state lower bound for accepting unary languages with isolated cut point on the one-way probabilistic model. Moreover, we exhibit one-way quantum finite automata that, for any m, accept Lm with isolated cut point and only two states. These results are settled within a survey on unary automata aiming to compare the descriptional power of deterministic, nondeterministic, probabilistic and quantum paradigms

    26. Theorietag Automaten und Formale Sprachen 23. Jahrestagung Logik in der Informatik: Tagungsband

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    Der Theorietag ist die Jahrestagung der Fachgruppe Automaten und Formale Sprachen der Gesellschaft für Informatik und fand erstmals 1991 in Magdeburg statt. Seit dem Jahr 1996 wird der Theorietag von einem eintägigen Workshop mit eingeladenen Vorträgen begleitet. Die Jahrestagung der Fachgruppe Logik in der Informatik der Gesellschaft für Informatik fand erstmals 1993 in Leipzig statt. Im Laufe beider Jahrestagungen finden auch die jährliche Fachgruppensitzungen statt. In diesem Jahr wird der Theorietag der Fachgruppe Automaten und Formale Sprachen erstmalig zusammen mit der Jahrestagung der Fachgruppe Logik in der Informatik abgehalten. Organisiert wurde die gemeinsame Veranstaltung von der Arbeitsgruppe Zuverlässige Systeme des Instituts für Informatik an der Christian-Albrechts-Universität Kiel vom 4. bis 7. Oktober im Tagungshotel Tannenfelde bei Neumünster. Während des Tre↵ens wird ein Workshop für alle Interessierten statt finden. In Tannenfelde werden • Christoph Löding (Aachen) • Tomás Masopust (Dresden) • Henning Schnoor (Kiel) • Nicole Schweikardt (Berlin) • Georg Zetzsche (Paris) eingeladene Vorträge zu ihrer aktuellen Arbeit halten. Darüber hinaus werden 26 Vorträge von Teilnehmern und Teilnehmerinnen gehalten, 17 auf dem Theorietag Automaten und formale Sprachen und neun auf der Jahrestagung Logik in der Informatik. Der vorliegende Band enthält Kurzfassungen aller Beiträge. Wir danken der Gesellschaft für Informatik, der Christian-Albrechts-Universität zu Kiel und dem Tagungshotel Tannenfelde für die Unterstützung dieses Theorietags. Ein besonderer Dank geht an das Organisationsteam: Maike Bradler, Philipp Sieweck, Joel Day. Kiel, Oktober 2016 Florin Manea, Dirk Nowotka und Thomas Wilk

    The Block Universe: A Philosophical Investigation in Four Dimensions

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    The aim of this doctoral dissertation is to closely explore the nature of Einstein’s block universe and to tease out its implications for the nature of time and human freedom. Four questions, in particular, are central to this dissertation, and set out the four dimensions of this philosophical investigation: (1) Does the block universe view of time follow inevitably from the theory of special relativity? (2) Is there room for the passage of time in the block universe? (3) Can we distinguish past from future in the block universe? (4) Is there room for human freedom in the block universe? Although the answer of most philosophers would be yes, triple no, my own answer, controversially, is no, triple yes. I thereby challenge the status quo with respect to each of these metaphysical questions, and argue that none of these questions can be answered from looking at physics alone. Physics may constrain our metaphysics, but it certainly does not settle it. What is needed in order to answer these questions, are additional metaphysical assumptions that fall outside the scope of modern physics. My primary goal in this dissertation, therefore, is not to settle the debates on the nature of time and human freedom, but to clarify them by expliciting the metaphysical assumptions that are otherwise left implicit

    MAFTIA Conceptual Model and Architecture

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    This document builds on the work reported in MAFTIA deliverable D1. It contains a refinement of the MAFTIA conceptual model and a discussion of the MAFTIA architecture. It also introduces the work done in WP6 on verification and assessment of security properties, which is reported on in more detail in MAFTIA deliverable D

    Conceptual Model and Architecture of MAFTIA

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    This deliverable builds on the work reported in [MAFTIA 2000] and [Powell and Stroud 2001]. It contains a further refinement of the MAFTIA conceptual model and a revised discussion of the MAFTIA architecture. It also introduces the work done in MAFTIA on verification and assessment of security properties, which is reported on in more detail in [Adelsbach and Creese 2003

    THE ECOLOGY OF POOR FEN & WILLOW CARR ON GOSS MOOR NNR, CORNWALL

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    Goss Moor NNR is a unique, rare and nationally-important wetland habitat in Mid- Cornwall. The majority of the habitats were created as a result of a long history of tin-stream mining, which ceased in the early 1900s. Phytosociological surveys of poor-fen and willow carr communities provide the first formal descriptions of the vegetation at this site. The poor-fen survey revealed twelve poor-fen vegetation types, which were distributed along a primary environmental gradient of organic matter depth, surface water height and bare substrate. Separation of the poor-fen communities by a moisture gradient was considered as spatial evidence for hydroseral succession, which begins with the colonisation of open-water pools created by tin excavations. The Salix cinerea ssp. oleifolia willow carr was divided by eight understorey communities, according to age, defined by reference to five sets of aerial photographs of Goss Moor taken over the last six decades. The average number of poor-fen species per unit area in the understorey generally decreased with age. This relationship was related to the increase in canopy cover and, therefore, shade. Willow was found to invade areas with the greatest amounts of accumulated organic material and a low water table. In the oldest and driest willow, oak saplings were found, indicating the beginning of secondary woodland. An architectural analysis of willow showed that useful age descriptors were the height of the first fork, the number of live secondary shoots, tree height and dbh, all of which generally increased with age. Spatial successional patterns were characterised using the lattice-wombling technique in three large rectangles or 'tranomes'. Plant communities were associated with either abrupt or diffuse boundary types. Abrupt boundaries or ecotones were found between heath communities and densely vegetated tall-herb fen and species-poor willow carr wetland vegetation. Diffuse or ecocline transitions occurred between communities with subtle differences in their composition. Spatial relationships between swamp and poor-fen communities were taken as evidence for space-for- time successions, these patterns varied according to location and microtopography. Investigations into the water regime showed water depth was governed by substrate heterogeneity. Homogeneous microtopography was associated with deep inundations and greatest amplitude in water depth, and most closely resembled rainfall fluctuations. The most complex microtopography resulted from the most intense tin-streaming activity. Therefore the anthropogenic history of Goss Moor plays an important role in governing the contemporary water regime and vegetation distribution. Of the wetland communities, rush pasture was the driest and poor-fen the wettest. The communities of open habitats were wetter than the willow communities. The youngest willow community was drier in the summer than the other five vegetation types studied, which was indicative of the conditions necessary for willow scrub colonisation to take place. The N:P ratio revealed that nitrogen was the limiting nutrient in all of the wetland vegetation types suggesting an early stage of successional development. High water levels were thought to be responsible for the prevalence of N-limitation on Goss Moor, creating deoxygenated substrates and leading to the demise of nitrifying bacteria and thus a reduction in the rate of soil N mineralisation. Plant strategies were used to classify the species from a number of wetland communities ranging from open-water pools to willow carr, in order to apply them to Grime's triangular model. The ten communities were ordered into a logical successional sequence. However, the model needs to be modified to account for succession in the aquatic environment. Based on the findings of this thesis, a number of suggestions were made for the effective management of the wetland habitats on Goss Moor. These include: evaluation of willow scrub before removal so those areas of vegetation subsequently opened-up can be monitored; and the creation of new ponds to encourage the growth of certain poor-fen communities, which are species-rich, but only account for a small area of the whole resource

    From universal morphisms to megabytes: A Baayen space odyssey

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    BEHAVIORISM AND LOGICAL POSITIVISM: A REVISED ACCOUNT OF THE ALLIANCE (VOLUMES I AND II)

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    The primary aim of this work is to show that the widespread belief that the major behaviorists drew importantly upon logical positivist philosophy of science in formulating their approach to psychology is ill-founded. Detailed historical analysis of the work of the neobehaviorists Edward C. Tolman, Clark L. Hull, and B. F. Skinner leads to the following conclusions: (1) each did have significant contact with proponents of logical positivism; but (2) their sympathies with logical positivism were quite limited and were restricted to those aspects of logical positivism which they had already arrived at independently; (3) the methods which they are alleged to have imported from logical positivism were actually derived from their own indigenous conceptions of knowledge; and (4) each major neobehaviorist developed and embraced a behavioral epistemology which, far from resting on logical positivist assumptions, actually conflicted squarely with the anti-psychologism that was a cornerstone of logical positivism. It is suggested that the myth of an alliance between behaviorism and logical positivism arose from the incautious interpretations of philosophical reconstructions as historical conclusions. This and other historiographical issues are discussed in the concluding chapter, where it is argued that the anti-psychologism of the logical positivists is an unnecessary impediment to a fuller understanding of the phenomenon of knowledge
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