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Hrvatski arhiv weba

Hrvatski arhiv weba (HAW) zbirka je odabranih sadržaja preuzetih s interneta i pohranjenih na računalnom poslužitelju Nacionalne i sveučilišne knjižnice u Zagrebu. Njegova je svrha preuzimanje i trajno čuvanje publikacija s interneta kao dijela hrvatske kulturne baštine. Dane su osnovne informacije o tom arhivu

Iz stranih časopisa

U tekstu je dan popis radova koji su objavljeni u stranim časopisima

Hrvatski arhiv weba

Hrvatski arhiv weba (HAW) zbirka je odabranih sadržaja preuzetih s interneta i pohranjenih na računalnom poslužitelju Nacionalne i sveučilišne knjižnice u Zagrebu. Njegova je svrha preuzimanje i trajno čuvanje publikacija s interneta kao dijela hrvatske kulturne baštine. Dane su osnovne informacije o tom arhivu

An abstract data type to handle vague spatial objects based on the fuzzy model

Crisp spatial data are geometric features with exact location on the extent and well-known boundaries. On the other hand, vague spatial data are characterized by inaccurate locations or uncertain boundaries. Despite the importance of vague spatial data in spatial applications, few related work indeed implement vague spatial data and they do not define abstract data types to enable the management of vague spatial data by using database management systems. In this sense, we propose the abstract data type FuzzyGeometry to handle vague spatial data based on the fuzzy model. FuzzyGeometry was developed as a PostgreSQL extension and its implementation is open source. It offers management for fuzzy points and fuzzy lines. As a result, spatial applications are able to access the PostgreSQL to handle vague spatial objects.FAPESPCAPESCNP

Embedding vague spatial objects into spatial databases using the VagueGeometry abstract data type

Spatial vagueness has been required by geoscientists to handle vague spatial objects, i.e., spatial objects that do not have exact locations, strict boundaries, or sharp interiors. However, there is a gap in the literature in how to handle these objects in spatial database management systems since they mainly provide support to crisp spatial objects, i.e., objects that have well-defined locations, boundaries, and interiors. In this paper, we fill this gap by proposing VagueGeometry, a novel abstract data type that handles vague spatial objects, includes an expressive set of vague spatial operations, and its implementation is open source. Experimental results show that VagueGeometry improved the performance of spatial queries with vague topological predicates from 23% up to 84% if compared with functionalities available in current spatial databases.FAPESPCAPESCNP

Modeling vague spatial data warehouses using the VSCube conceptual model

Although many real world phenomena are vague and characterized by having uncertain location or vague shape, existing spatial data warehouse models do not support spatial vagueness and then cannot properly represent these phenomena. In this paper, we propose the VSCube conceptual model to represent and manipulate shape vagueness in spatial data warehouses, allowing the analysis of business scores related to vague spatial data, and therefore improving the decision-making process. Our VSCube conceptual model is based on the cube metaphor and supports geometric shapes and the corresponding membership values, thus providing more expressiveness to represent vague spatial data. We also define vague spatial aggregation functions (e.g. vague spatial union) and vague spatial predicates to enable vague SOLAP queries (e.g. intersection range queries). Finally, we introduce the concept of vague SOLAP and its operations (e.g. drill-down and roll-up). We demonstrate the applicability of our model by describing an application concerning pest control in agriculture and by discussing the reuse of existing models in the VSCube conceptual model.FAPESP (grant #2011/23904-7)CAPESCNPqINEPFINE