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The paper is concerned with modelling object-oriented distributed computational systems. Systems are modeled by specifying their states and processes. Processes of a system are defined as activities in a universe of objects, each object with a set of possible states, each activity changing states of some objects and establishing or destroying relations among objects. Partial operations on processes...
In this report we propose a new approach to integration of distributed heterogeneous resources on the basis of a canonical object-oriented database model, a query language and updateable database views. Views are used as wrappers/mediators on top of local servers and as a data integration facility for global applications. Views support location, implementation and replication transparency. Because...
The claim is that blind persons can perceive objects like door, pillar, ditch, elevator, passage, room, hali, building, Street, etc,, haying only mobile cellular phones. The primary goal of all positioning systems is to determine the user's position as precisely as possible, whereas the main purpose of our project is to provide a blind person with the ability to locate an object and then to perceive...
Non-deterministic matrices (Nmatrices) are multiple-valued structures in which the value assigned by a valuation to a complex formula can be chosen non-deterministically out of a certain nonempty set of options. We consider two different types of semantics which are based on Nmatrices: the dynamic one and the static one (the latter is new here). We use the Rasiowa-Sikorski (R-S) decomposition methodology...
W niniejszej pracy analizowany jest model sieci idiotypowej zaproponowany w artykule autorstwa Farmer et al. w 1986 roku i wykorzystujący ciągi binarne do reprezentacji przeciwciał i antygenów. Jak pisali de Castro i Timmis o tej pracy w swojej książce w 2002 roku: "Ich (tj. Farmera i pozostałych autorów) prace mają wyjątkowe znaczenie, ponieważ stanowią pierwsze podejście do połączenia w całość...
In this paper we discuss three new characterizations of n-dimensional Archimedean ąuasi-copulas. The first (differential) characterization is a generalization of the analogous fact for 2-dimensional Archimedean copulas. The second (asymptotic) characterization concerns a representation of Archimedean ąuasi-copulas as the limit of an almost uniformly convergent sequence of functions which depend on...
Recursive queries arę reąuired for many tasks of database applications. Among them we can mention Bill-Of-Material (BOM), various kinds of networks (transportation, telecommunication, etc.), processing semi-structured data (XML, RDF), and so on. The support for recursive queries in current query languages is limited and lacks of theoretical foundations. In particular, this concerns corresponding extensions...
Niniejszy raport stanowi omówienie Teorii Reprezentacji Dyskursu (w skrócie DRT) w postaci przedstawionej przez Kampa i Reylego (1993). Prezentowana jest zarówno podstawowa wersja teorii, jak i dwa jej rozszerzenia: jedno dotyczące reprezentacji liczby mnogiej (znaczniki zbiorowe) i rozszerzonych kwantyfikatorów (DRT_Pl), drugie kwestii związanych z czasem i aspektem (DRT_T). Przedstawiona jest także...
The paper studies the properties of orthomodular posets. The interest comes from the fact, that the set of all regions of a 2-structure (a transi-tion system) is a coherent orthomodular poset. This algebraic structure is gaining the importance in the area of distributed systems. In fact, there is a conjucture about the duality between the category of orthomodular posets and the category of 2-structures...
W pracy wprowadzamy nowe pojęcie "wartości proceduralnych" dla gier kooperacyjnych z wypłatami ubocznymi. Wartości takie są wyznaczone przez procedury podziału krańcowych wkładów graczy pomiędzy nich i graczy już obecnych w koalicji powstającej przy losowym uporządkowaniu graczy. Najprostszą wartościąproceduralną jest wartość Shapleya, otrzymywana przy procedurze, według której każdy gracz...
The problem of testing statistical hypotheses of independence of two multiresponse variables is considered. This is a specific inferential environment to analyze certain patterns particularly for the ąuestionnaire data. Data analyst normally looks for certain combination of responses being morę freąuently chosen than the other ones. As a result of experimental study we consider an algorithm that can...
In this report we propose a new approach to types and static type checking in object-oriented database query and programming languages. In contrast to typical approaches to types which involve very advanced mathematical concepts we present a type system from the practitioners' point of view. We argue that many features of current object-oriented query/programming languages, such as ellipses, automatic...
We present a new approach to optimization of ąuery languages using materialization of resułts previously answered ąueries. It is based on the stack-based approach (SBA) to object-oriented ąuery languages, which assumes the description of semantics in the form of abstract implementation of ąuery/programming language constructs. The semantics is expressed in terms of naming, scoping and binding. It...
We deal with a game-theoretic framework involving a finite number of infinite populations, members of which have a finite number of available strategies. The payoff of each individual depends on her own action and distributions of actions of individuals in all populations. A method to find all equilibria is discussed which requires the search through all nonempty subsets of the types' strategy sets,...
Praca dotyczy algebr, które można otrzymać przez wyposażenie zbiorów procesów sieci Petriego w składanie sekwencyjne i równoległe. Rozważane algebry są kategoriami z dodatkową strukturą i z dodatkowymi własnościami. Dowodzi się, że wszystkie struktury algebraiczne o takich własnościach dają się przedstawiać jako algebry procesów sieci Petriego.
W pracy wprowadzono pojęcie generatora diagonalnego kopuły archimedesowskiej. Podano ogólny sposób konstrukcji parametrycznej rodziny generatorów diagonalnych, wyznaczonej przez dystrybuantę. Pokazano, że z taką dystrybuantą w naturalny sposób związana jest parametryczna grupa przekształceń mająca generator pochodzący z pewnej rodziny funkcji. Podano równanie różniczkowe w zależności od elementów...
It has been observed that various synchronisation operators that underly modular design of concurrent systems can be explained as {\em pullbacks in suitable categories of concurrent systems. Here, the boundaries of such approach are investigated. For this purpose we study the issue of completeness in categories of trace monoids. It turns out that (finite) completeness is achieved if trace monoids...
The paper proposes how to use static analysis to extract an abstract model of a system. The method uses techniques of program slicing to examine syntax of a system modeled as a set of timed automata with discrete data, a common input formalism of model checkers dealing with time. The method is property driven. The abstraction is exact with respect to all properties expressed in the temporal logic...
In this paper we offer a methodology for verifying correctness of (timed) security protocols whose actions are parametrised with time. To this aim the model of a protocol involves delays and timeouts on transitions, and sets time constraints on actions to be executed. Our approach consists in specifying a security protocol, possibly with timestamps, in a higher-level language and translating automatically...
The paper is concerned with algebras whose elements can be used to represent runs of a system, called processes. These algebras, called behaviour algebras, are categories with respect to a partial binary operation called seąuential composition, and they arę partial monoids with respect to a partial binary operation called parallel composition. They are characterized by axioms such that their elements...
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