A fine-grain architecture for relational database aggregationoperations

The design and simulation of a bit-sliced processor for relational database aggregation functions, are discussed. The processor, which addresses an important, computationally expensive problem in database computers, takes two tuples as input (one bit at a time) and returns two bits as output every clock cycle. A larger aggregation unit uses a number of identical slice processors, connected according to odd-even network topology, to achieve improved performance on a parallel pipelined processor. The data processing time is completely overlapped with the input and output of data to and from the unit. The design is independent of the tuple size, and since a bit-serial computation is used, the system requires limited interconnection     

Computational complexity of sorting and joining relations withduplicates

It is shown that the existence of duplicate values in some attribute columns has a significant impact on the computational complexity of the sorting and joining operations. This is especially true when the number of distinct tuple values is a small fraction of the total number of tuples. The authors characterize a multirelation M (n, L) by its cardinality n and the number of distinct elements L it contains. Under this characterization, the worst time complexity of sorting such a multirelation with binary comparisons as basic operations is investigated. Upper and lower bounds on the number of three-branch comparisons needed to sort such a multirelation are established. Thereafter, the methodology used to study the complexity of sorting is applied to the natural join operation. It is shown that the existence of duplicate values in the join attribute columns can be exploited to reduce the computational complexity of the natural join operation     

A real-time industrial pattern classification system

Using the partitioned matrix approach, a parallel hardware architecture for a parametric (Bayes) classifier is designed. The architecture consists of simple, regularly structured processing elements operating in parallel. As a result, the proposed design is suitable for VLSI implementation. A comparative analysis shows that the approach is more efficient and can significantly reduce the cost required for implementing the classifier, while maintaining high speed     

Web Services for Geographic Information Systems

A surge in Web services and applications for geographic information systems (GISs) has made large spatial-data archives available over the Internet. Significant accomplishments in GIS Web services have led to several exemplifying map and image services that adhere to Web services standards and provide geospatial data and digital maps to enterprise developers.     

3D mapping of an interactive synthetic environment

Traditional geospatial information systems (GIS) use geographically referenced data to produce highly accurate digital maps. These two-dimensional maps include well-recognized symbols that represent features such as mountains, forests, buildings, and transportation networks. Although this flat view provides an excellent means of orienting the user to the general nature and location of the geographic features for a given area, it does not provide the full experiential value that comes from immersion within a 3D environment. The authors, working in conjunction with the University of New Orleans' Computer Science Department, developed a 3D-GIS to assist the US Marine Corps with mission preparation and rehearsal. It also provides on-site awareness during actual field operations in urban areas. Going beyond presenting stereoscopic views of an area or merely applying photo textures to highly simplified geometric shapes, they created an environment that replicates its real-world counterpart by including detailed 3D objects. The article details the design considerations they faced as well as the implementation and structural overview for the entire system