Large scientific applications which rely on highly parallel computational analysis require highly parallel data access. We describe an object-oriented, scientificdatabase system that achieves nearly linear scale-up o...
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Large scientific applications which rely on highly parallel computational analysis require highly parallel data access. We describe an object-oriented, scientificdatabase system that achieves nearly linear scale-up over large, million object data sets. Of primary importance are those features which seem central to the development of this, or any other parallel database system. These include techniques of object distribution, of multi-operator parallelism, and of indirect object referencing. It also appears to require a query server architecture instead of the more common page server configurations.
Algorithm for evaluating joins of `trapezoids' without using minimum bounding rectangles (MBR) is developed. The algorithms can be used to evaluate spatial joins for polygons. One possibility is to decompose polyg...
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Algorithm for evaluating joins of `trapezoids' without using minimum bounding rectangles (MBR) is developed. The algorithms can be used to evaluate spatial joins for polygons. One possibility is to decompose polygons into trapezoids and apply a trapezoid join algorithm. This approach is efficient for `I/O bounded polygons'.
The words metadata and meta-information were coined on the model of meta-philosophy, meta-language, and the such, in which the prefix meta- expresses reflexive application of a concept to itself. This provides the sim...
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The words metadata and meta-information were coined on the model of meta-philosophy, meta-language, and the such, in which the prefix meta- expresses reflexive application of a concept to itself. This provides the simplest, but most widely accepted definition of these words: metadata are data about data;and meta-information is information about information. One of the ways to discover differences in meaning is to confront packages that explicitly state metadata management as one of their functions. Three packages: Enhanced Meta-Information management Architecture (EMMA);Blaise;and GESMES;were compared and analyzed to established distinction based on the intended use of metadata.
Many real world systems and applications require information management components that provide support for managing imprecise data. There have thus been several proposals for extending relational database systems in ...
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Many real world systems and applications require information management components that provide support for managing imprecise data. There have thus been several proposals for extending relational database systems in order to represent as well as query such imprecise data. Little work, however, has been done in modeling uncertainty at the conceptual schema level and in developing design methodologies for developing fuzzy relational databases (FRDBs). To fill this gap, a design methodology for FRDBs is proposed. This methodology contains extensions for representing the imprecision of data in the Entity-Relationship (ER) data model, and a set of steps for the derivation of a FRDB from this extended ER model. As a case study this methodology has been applied to the design of a control database for semiconductor manufacturing.
The analysis of time series is a central issue in economic research and many other scientific applications. However, the data management functionality for this field is not provided by general-purpose DBMSs. Therefore...
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The analysis of time series is a central issue in economic research and many other scientific applications. However, the data management functionality for this field is not provided by general-purpose DBMSs. Therefore, we propose a data model of a specialized Time Series management System (TSMS) which accounts for these needs. The model is centered around an object-oriented kernel that offers the classes and value types needed for the target applications. The model provides base classes for multivariate time series and for groups as a means to hierarchically partition the time series space. The system offers a computationally complete data manipulation language including capabilities to query time series and groups. An elaborate array model is supported to account for the functional needs of statistical computations. Furthermore, a customizable calendar system providing a variety of predefined calendars is included.
We present preliminary results on the development of a prototype database system demonstrating the utility of the integration of environmental metadata within an online analytical processing environment. We utilized e...
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We present preliminary results on the development of a prototype database system demonstrating the utility of the integration of environmental metadata within an online analytical processing environment. We utilized existing data derived from CD-ROMs of the National Snow and Ice Data Center (NSIDC), the Consortium for international Earth Science Information Network (CIESIN) and the U.S. Geological Survey (USGS). We populated a prototype metadata database whose architecture facilitates the scientific and statistical investigations of geophysical parameters associated with the polar regions, allowing for data fusion from other regions and earth science disciplines, facilitating interdisciplinary studies. The user can extract information combining the knowledge of two disparate sources of geophysical data to allow a query that would result in a useful product. Furthermore, we demonstrate the utility of allowing access to this database via the World Wide Web using an interface to the underlying Oracle databasemanagement system. Figure 1 summarizes the overarching approach.
The Internet has spawned an insatiable appetite for information. This appetite cannot be satisfied without useful search tools. These tools rely on metadata in order to give targeted and meaningful results to searches...
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ISBN:
(纸本)0769516327
The Internet has spawned an insatiable appetite for information. This appetite cannot be satisfied without useful search tools. These tools rely on metadata in order to give targeted and meaningful results to searches, and the Internet world is realising that metadata, its management, and the means to search these metadata, are an integral part of the Internet world. The EC 5th Framework project COSMOS [1] aims to demonstrate the use of metadata in this way by building a common model for describing a statistical data set in terms of metadata, populating a metadata registry with descriptions consistent with the model, and searching the registry to find the data sets, and finally to access the data sets in the relevant repository.
This paper presents the work carried out in the Prometheus project and its motivation, taxonomy. Taxonomy presents challenges to common database systems. Because of its complexity and the necessary treatments applied ...
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This paper presents the work carried out in the Prometheus project and its motivation, taxonomy. Taxonomy presents challenges to common database systems. Because of its complexity and the necessary treatments applied to its data, common database models such as the relational, the object-oriented, of even graph models are not able to support taxonomic applications fully. Our approach is the extension of a object-oriented database model with explicit relationships in order to support new features and thereby offer the necessary level of service for developing taxonomic applications.
Given two,sets A and B of multidimensional objects, the all-nearest-neighbors (ANN) query retrieves for each object in A its nearest neighbor in B. Although this operation. is common in several applications, it has no...
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ISBN:
(纸本)0769521460
Given two,sets A and B of multidimensional objects, the all-nearest-neighbors (ANN) query retrieves for each object in A its nearest neighbor in B. Although this operation. is common in several applications, it has not received much attention in the database literature. In this paper we study alternative methods for processing ANN queries depending on whether A and B are indexed. Our algorithms are evaluated through extensive experimentation using synthetic and real datasets. The performance studies show that they are an order of magnitude faster than a previous approach based on closest-pairs query processing.
A relation is an unordered collection of records. Often, however, there is an underlying order (e.g., a sequence of stock prices), and users want to pose queries that reflect this order (e.g., find a weekly moving ave...
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A relation is an unordered collection of records. Often, however, there is an underlying order (e.g., a sequence of stock prices), and users want to pose queries that reflect this order (e.g., find a weekly moving average). SQL provides no support for posing such queries. In this paper, we show how a rich class of queries reflecting sort order can be naturally expressed and efficiently executed with simple extensions to SQL.
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