236 research outputs found
Coalgebraic Geometric Logic: Basic Theory
Using the theory of coalgebra, we introduce a uniform framework for adding
modalities to the language of propositional geometric logic. Models for this
logic are based on coalgebras for an endofunctor on some full subcategory of
the category of topological spaces and continuous functions. We investigate
derivation systems, soundness and completeness for such geometric modal logics,
and we we specify a method of lifting an endofunctor on Set, accompanied by a
collection of predicate liftings, to an endofunctor on the category of
topological spaces, again accompanied by a collection of (open) predicate
liftings. Furthermore, we compare the notions of modal equivalence, behavioural
equivalence and bisimulation on the resulting class of models, and we provide a
final object for the corresponding category
Goldblatt-Thomason Theorems for Modal Intuitionistic Logics
We prove Goldblatt-Thomason theorems for frames and models of a wide variety
of modal intuitionistic logics, including ones studied by Wolter and
Zakharyaschev, Goldblatt, Fischer Servi, and Plotkin and Sterling. We use the
framework of dialgebraic logic to describe most of these logics and derive
results in a uniform way
Modal meet-implication logic
We extend the meet-implication fragment of propositional intuitionistic logic
with a meet-preserving modality. We give semantics based on semilattices and a
duality result with a suitable notion of descriptive frame. As a consequence we
obtain completeness and identify a common (modal) fragment of a large class of
modal intuitionistic logics.
We recognise this logic as a dialgebraic logic, and as a consequence obtain
expressivity-somewhere-else. Within the dialgebraic framework, we then
investigate the extension of the meet-implication fragment of propositional
intuitionistic logic with a monotone modality and prove completeness and
expressivity-somewhere-else for it
Modal Logics for Mobile Processes Revisited
We revisit the logical characterisations of various bisimilarity relations for the finite fragment of the ?-calculus. Our starting point is the early and the late bisimilarity, first defined in the seminal work of Milner, Parrow and Walker, who also proved their characterisations in fragments of a modal logic (which we refer to as the MPW logic). Two important refinements of early and late bisimilarity, called open and quasi-open bisimilarity, respectively, were subsequently proposed by Sangiorgi and Walker. Horne, et. al., showed that open and quasi-bisimilarity are characterised by intuitionistic modal logics: OM (for open bisimilarity) and FM (for quasi-open bisimilarity). In this work, we attempt to unify the logical characterisations of these bisimilarity relations, showing that they can be characterised by different sublogics of a unifying logic. A key insight to this unification derives from a reformulation of the four bisimilarity relations (early, late, open and quasi-open) that uses an explicit name context, and an observation that these relations can be distinguished by the relative scoping of names and their instantiations in the name context. This name context and name substitution then give rise to an accessibility relation in the underlying Kripke semantics of our logic, that is captured logically by an S4-like modal operator. We then show that the MPW, the OM and the FM logics can be embedded into fragments of our unifying classical modal logic. In the case of OM and FM, the embedding uses the fact that intuitionistic implication can be encoded in modal logic S4
Dualities in modal logic
Categorical dualities are an important tool in the study of (modal) logics. They offer conceptual understanding and enable the transfer of results between the different semantics of a logic. As such, they play a central role in the proofs of completeness theorems, Sahlqvist theorems and Goldblatt-Thomason theorems. A common way to obtain dualities is by extending existing ones. For example, Jonsson-Tarski duality is an extension of Stone duality. A convenient formalism to carry out such extensions is given by the dual categorical notions of algebras and coalgebras. Intuitively, these allow one to isolate the new part of a duality from the existing part. In this thesis we will derive both existing and new dualities via this route, and we show how to use the dualities to investigate logics. However, not all (modal logical) paradigms fit the (co)algebraic perspective. In particular, modal intuitionistic logics do not enjoy a coalgebraic treatment, and there is a general lack of duality results for them. To remedy this, we use a generalisation of both algebras and coalgebras called dialgebras. Guided by the research field of coalgebraic logic, we introduce the framework of dialgebraic logic. We show how a large class of modal intuitionistic logics can be modelled as dialgebraic logics and we prove dualities for them. We use the dialgebraic framework to prove general completeness, Hennessy-Milner, representation and Goldblatt-Thomason theorems, and instantiate this to a wide variety of modal intuitionistic logics. Additionally, we use the dialgebraic perspective to investigate modal extensions of the meet-implication fragment of intuitionistic logic. We instantiate general dialgebraic results, and describe how modal meet-implication logics relate to modal intuitionistic logics
Positive Modal Logic Beyond Distributivity
We develop a duality for (modal) lattices that need not be distributive, and
use it to study positive (modal) logic beyond distributivity, which we call
weak positive (modal) logic. This duality builds on the Hofmann, Mislove and
Stralka duality for meet-semilattices. We introduce the notion of
-persistence and show that every weak positive modal logic is
-persistent. This approach leads to a new relational semantics for weak
positive modal logic, for which we prove an analogue of Sahlqvist
correspondence result
Создание монумента «Возрождение крымскотатарского народа» как культурное явление в жизни крымского общества
В статье автором охарактеризован градостроительный объект Монумент «Возрождение крымскотатарского народа» как культурное явление в жизни крымского общества, призванное внести вклад в процесс воспитания духовности и культуры в молодых людях.У статті автором охарактеризовано містобудівельний об’єкт Монумент «Відродження кримськотатарського народу» як культурне явище у житті кримського суспільства, що призвание донести внесок у процес виховання духовності та культури молоді.The author describes a monument „Rebirth of the Crimean Tatars” as a cultural phenomenon in the life of the Crimean society, which can contribute in the process of spiritual and cultural upbringing of young people
IPD-MHC 2.0:An improved inter-species database for the study of the major histocompatibility complex
The IPD-MHC Database project (http://www.ebi.ac.uk/ipd/mhc/) collects and expertly curates sequences of the major histocompatibility complex from non-human species and provides the infrastructure and tools to enable accurate analysis. Since the first release of the database in 2003, IPD-MHC has grown and currently hosts a number of specific sections, with more than 7000 alleles from 70 species, including non-human primates, canines, felines, equids, ovids, suids, bovins, salmonids and murids. These sequences are expertly curated and made publicly available through an open access website. The IPD-MHC Database is a key resource in its field, and this has led to an average of 1500 unique visitors and more than 5000 viewed pages per month. As the database has grown in size and complexity, it has created a number of challenges in maintaining and organizing information, particularly the need to standardize nomenclature and taxonomic classification, while incorporating new allele submissions. Here, we describe the latest database release, the IPD-MHC 2.0 and discuss planned developments. This release incorporates sequence updates and new tools that enhance database queries and improve the submission procedure by utilizing common tools that are able to handle the varied requirements of each MHC-group
История изучения имен прилагательных в крымскотатарском языке
Целью данной статьи является рассмотрение степени изученности имени прилагательного в
крымскотатарском языке как самостоятельной части речи в лингвистических трудах XIX – XX вв., а также
анализ основных грамматических категорий имени прилагательного
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