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Analysis of trajectory data is the key to a growing number of applications aiming at global understanding and management of complex phenomena that involve moving objects (e.g. worldwide courier distribution, city traffic management, bird migration monitoring). Current DBMS support for such data is limited to the ability to store and query raw movement (i.e.(More)
We present a framework for the autonomous discovery and selection of Semantic Web services based on their QoS properties. The novelty of our approach is the wide use of semantic technologies for a customizable discovery, which enables both the service users and providers to flexibly specify their matching models for QoS and the corresponding environmental(More)
Query processing in traditional Database Management Systems (DBMS) has been extensively studied in the literature and adopted in industry. Such success is, in part, due to the performance of their Query Execution Engines (QEE) for supporting the execution of traditional queries. With the advent of the web and its semi-structured data model, new query(More)
Learning Content Management Systems (LCMS) store and manage e-learning content and play an important role in the development of Distance Learning technology. ROSA (Repository of Objects with Semantic Access) is a LCMS that provides the creation, storage, reuse, retrieval and management of learning objects (LO). In ROSA, course structure and content (LOs)(More)
In the present study, we evaluated the effects of the ethanolic extract (EE) of Cipura paludosa on locomotor, and anxiety- and depression-like behaviors of adult rats exposed to MeHg during early development. Additionally, the antioxidant enzymes catalase (CAT) and selenium-glutathione peroxidase (Se-GPx) were measured in cortical, hippocampal, and(More)
Directory services are a genuine constituent of any distributed architecture which facilitate binding attributes to names and then querying this information, i.e., announcing and discovering resources. In such contexts, especially in a business environment, quality of service (QoS) and non-functional properties are usually the most important criteria to(More)
Scientific workflows have emerged as a basic abstraction for structuring and executing scientific experiments in computational environments. In many situations, these workflows are computationally and data intensive, thus requiring execution in large-scale parallel computers. However, parallelization of scientific workflows remains low-level, ad-hoc and(More)
LeSelect is a mediator system which allows scientists to publish their resources (data and programs) so they can be transparently accessed. The scientists can typically issue queries which access distributed published data and involve the execution of expensive functions (corresponding to programs). Furthermore, the queries can involve large objects such as(More)
Grid services provide an important abstract layer on top of heterogeneous components (hardware and software) that take part into a grid environment. We are developing a data grid service prototype that aims at providing transparent use of grid resources to data intensive scientific applications. Our prototype was designed having as target three main issues:(More)