The Experts below are selected from a list of 195 Experts worldwide ranked by ideXlab platform
Mirta Baranović - One of the best experts on this subject based on the ideXlab platform.
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MIPRO - Managing moving objects in the context of spatio-temporal data streams
2011Co-Authors: Emir Meskovic, Zdravko Galić, Mirta BaranovićAbstract:Managing moving objects in DSMS has recently been a focus of a relatively intense research. In this paper, we are concerned with data streams containing a location of a moving object at any time instant. Instead of using spatial and time instant data Types separately, for representing spatio-temporal characteristics of data streams, we propose a unified approach based on specialized temporal data Type Constructor. This Type Constructor, parameterized with a spatial Type representing objects location, yields a corresponding Type whose values are pairs, consisting of an instant of time and a value of spatial Type. With this approach, it is possible to represent temporal development of an objects' location within one time interval by using two consecutive values of this temporal data Type. Since moving object is basically obtained just by assembling these temporal developments whose time intervals are disjoint, we also propose an approach for extracting moving objects out of spatio-temporal data streams based on user-defined aggregate functions (UDAF) over spatio-temporal data Types. With this approach, it is possible to manage moving objects encapsulated within spatio-temporal data streams using SQL-like query language.
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Mobile Data Management (2) - Managing Moving Objects in Spatio-temporal Data Streams
2011 IEEE 12th International Conference on Mobile Data Management, 2011Co-Authors: Emir Meskovic, Zdravko Galić, Mirta BaranovićAbstract:Managing moving objects in DSMS has been a focus of a relatively intense research in recent years. In this paper, we are concerned with data stream tuples containing a location of a moving object at any time instant. Instead of using spatial and time instant data Types separately, for representing spatio-temporal component in such data streams, we propose a use of a specialized temporal data Type Constructor. This Type Constructor parameterized with a spatial Type representing objects location, yields a corresponding Type whose values are pairs, consisting of an instant in time and a value of spatial Type. With this approach, it is possible to represent temporal development of objects' location within one time interval by using two consecutive values of this temporal data Type. Since moving object is basically obtained just by assembling these temporal developments whose time intervals are disjoint, we also propose an approach for extracting moving objects out of spatio-temporal data streams based on user-defined aggregate functions (UDAF) over spatio-temporal data Types. With this approach, it is possible to manage moving objects encapsulated within spatio-temporal data streams using SQL-like query language.
Venanzio Capretta - One of the best experts on this subject based on the ideXlab platform.
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TPHOLs - A Type of Partial Recursive Functions
Lecture Notes in Computer Science, 2008Co-Authors: Ana Bove, Venanzio CaprettaAbstract:Our goal is to define a Type of partial recursive functions in constructive Type theory. In a series of previous articles, we studied two different formulations of partial functions and general recursion. We could obtain a Type only by extending the theory with either an impredicative universe or with coinductive definitions. Here we present a new Type Constructor that eludes such entities of dubious constructive credentials. We start by showing how to break down a recursive function definition into three components: the first component generates the arguments of the recursive calls, the second evaluates them, and the last computes the output from the results of the recursive calls. We use this dissection as the basis for the introduction rule of the new Type Constructor. Every partial recursive function is associated with an inductive domain predicate; evaluation of the function requires a proof that the input values satisfy the predicate. We give a constructive justification for the new construct by interpreting it into the base Type theory. This shows that the extended theory is consistent and constructive.
Emir Meskovic - One of the best experts on this subject based on the ideXlab platform.
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MIPRO - Managing moving objects in the context of spatio-temporal data streams
2011Co-Authors: Emir Meskovic, Zdravko Galić, Mirta BaranovićAbstract:Managing moving objects in DSMS has recently been a focus of a relatively intense research. In this paper, we are concerned with data streams containing a location of a moving object at any time instant. Instead of using spatial and time instant data Types separately, for representing spatio-temporal characteristics of data streams, we propose a unified approach based on specialized temporal data Type Constructor. This Type Constructor, parameterized with a spatial Type representing objects location, yields a corresponding Type whose values are pairs, consisting of an instant of time and a value of spatial Type. With this approach, it is possible to represent temporal development of an objects' location within one time interval by using two consecutive values of this temporal data Type. Since moving object is basically obtained just by assembling these temporal developments whose time intervals are disjoint, we also propose an approach for extracting moving objects out of spatio-temporal data streams based on user-defined aggregate functions (UDAF) over spatio-temporal data Types. With this approach, it is possible to manage moving objects encapsulated within spatio-temporal data streams using SQL-like query language.
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Mobile Data Management (2) - Managing Moving Objects in Spatio-temporal Data Streams
2011 IEEE 12th International Conference on Mobile Data Management, 2011Co-Authors: Emir Meskovic, Zdravko Galić, Mirta BaranovićAbstract:Managing moving objects in DSMS has been a focus of a relatively intense research in recent years. In this paper, we are concerned with data stream tuples containing a location of a moving object at any time instant. Instead of using spatial and time instant data Types separately, for representing spatio-temporal component in such data streams, we propose a use of a specialized temporal data Type Constructor. This Type Constructor parameterized with a spatial Type representing objects location, yields a corresponding Type whose values are pairs, consisting of an instant in time and a value of spatial Type. With this approach, it is possible to represent temporal development of objects' location within one time interval by using two consecutive values of this temporal data Type. Since moving object is basically obtained just by assembling these temporal developments whose time intervals are disjoint, we also propose an approach for extracting moving objects out of spatio-temporal data streams based on user-defined aggregate functions (UDAF) over spatio-temporal data Types. With this approach, it is possible to manage moving objects encapsulated within spatio-temporal data streams using SQL-like query language.
Ana Bove - One of the best experts on this subject based on the ideXlab platform.
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TPHOLs - A Type of Partial Recursive Functions
Lecture Notes in Computer Science, 2008Co-Authors: Ana Bove, Venanzio CaprettaAbstract:Our goal is to define a Type of partial recursive functions in constructive Type theory. In a series of previous articles, we studied two different formulations of partial functions and general recursion. We could obtain a Type only by extending the theory with either an impredicative universe or with coinductive definitions. Here we present a new Type Constructor that eludes such entities of dubious constructive credentials. We start by showing how to break down a recursive function definition into three components: the first component generates the arguments of the recursive calls, the second evaluates them, and the last computes the output from the results of the recursive calls. We use this dissection as the basis for the introduction rule of the new Type Constructor. Every partial recursive function is associated with an inductive domain predicate; evaluation of the function requires a proof that the input values satisfy the predicate. We give a constructive justification for the new construct by interpreting it into the base Type theory. This shows that the extended theory is consistent and constructive.
William R. Cook - One of the best experts on this subject based on the ideXlab platform.
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ECOOP - Feature-Oriented programming with object algebras
ECOOP 2013 – Object-Oriented Programming, 2013Co-Authors: Bruno C. D. S. Oliveira, Tijs Van Der Storm, Alex Loh, William R. CookAbstract:Object algebras are a new programming technique that enables a simple solution to basic extensibility and modularity issues in programming languages. While object algebras excel at defining modular features, the composition mechanisms for object algebras (and features) are still cumbersome and limited in expressiveness. In this paper we leverage two well-studied Type system features, intersection Types and Type-Constructor polymorphism, to provide object algebras with expressive and practical composition mechanisms. Intersection Types are used for defining expressive run-time composition operators (combinators) that produce objects with multiple (feature) interfaces. Type-Constructor polymorphism enables generic interfaces for the various object algebra combinators. Such generic interfaces can be used as a Type-safe front end for a generic implementation of the combinators based on reflection. Additionally, we also provide a modular mechanism to allow different forms of self-references in the presence of delegation-based combinators. The result is an expressive, Type-safe, dynamic, delegation-based composition technique for object algebras, implemented in Scala, which effectively enables a form of Feature-Oriented Programming using object algebras.
