Large Spatial Database Indexing with aX-tree

Spatial databases are optimized for the management of data stored based on their geometric space. Researchers through high degree scalability have proposed several spatial indexing structures towards this effect. Among these indexing structures is the X-tree. The existing X-trees and its variants are designed for dynamic environment, with the capability for handling insertions and deletions. Notwithstanding, the X-tree degrades on retrieval performance as dimensionality increases and brings about poor worst-case performance than sequential scan. We propose a new X-tree packing techniques for static spatial databases which performs better in space utilization through cautious packing. This new improved structure yields two basic advantage: It reduces the space overhead of the index and produces a better response time, because the aX-tree has a higher fan-out and so the tree always ends up shorter. New model for super-node construction and effective method for optimal packing using an improved str bulk-loading technique is proposed. The study reveals that proposed system performs better than many existing spatial indexing structure

Comparative Study of Fingerprint Database Indexing Methods

International audienceNowadays, there are large country-sized fingerprint databases for identification purposes, for border access controls and also for Visa issuance procedures around the world. Fingerprint indexing techniques aim to speed up the research process in automatic fingerprint identification systems. Therefore, several preselection, classification and indexing techniques have been proposed in the literature. However, the proposed systems have been evaluated with different experimental protocols, that makes it difficult to assess their performances. The main objective of this paper is to provide a comparative study of fingerprint indexing methods using a common experimental protocol. Four fingerprint indexing methods, using naive, cascade, matcher and Minutiae Cylinder Code (MCC) approaches are evaluated on FVC databases from the Fingerprint Verification Competition (FVC) using the Cumulative Matches Curve (CMC) and for the first time using also the computing time required. Our study shows that MCC gives the best compromise between identification accuracy and computation time

Database indexing for production MegaBLAST searches

Motivation: The BLAST software package for sequence comparison speeds up homology search by preprocessing a query sequence into a lookup table. Numerous research studies have suggested that preprocessing the database instead would give better performance. However, production usage of sequence comparison methods that preprocess the database has been limited to programs such as BLAT and SSAHA that are designed to find matches when query and database subsequences are highly similar

New generic indexing technology

There has been no fundamental change in the dynamic indexing methods supporting database systems since the invention of the B-tree twenty-five years ago. And yet the whole classical approach to dynamic database indexing has long since become inappropriate and increasingly inadequate. We are moving rapidly from the conventional one-dimensional world of fixed-structure text and numbers to a multi-dimensional world of variable structures, objects and images, in space and time. But, even before leaving the confines of conventional database indexing, the situation is highly unsatisfactory. In fact, our research has led us to question the basic assumptions of conventional database indexing. We have spent the past ten years studying the properties of multi-dimensional indexing methods, and in this paper we draw the strands of a number of developments together - some quite old, some very new, to show how we now have the basis for a new generic indexing technology for the next generation of database systems

Searching By Controlled Vocabulary or Free Text?

Discusses the factors to consider in online searching in libraries. Controlled vocabulary versus free text; Database; Indexing policies that dictate how the vocabulary is applied; Topic to be searched

FIT for purpose – the new FLARE Index to Treaties

The FLARE Index to Treaties which was launched in March 2009 on the Institute of Advanced Legal Studies web server, was conceived to fill a gap in the range of information finding tools available on the internet for the international lawyer. It is a fully searchable database indexing and listing over 1,500 of the most significant multilateral treaties concluded from 1856 onwards. This article describes the background to the development, the various ways in which the service can be used and technical issues in its construction and use.Preprint of an article by Dr Peter Clinch, Senior Subject Librarian for Law, Cardiff University, Wales, UK and Steven Whittle, Information Systems Manager, Institute of Advanced Legal Studies, University of London published online by LLRX.co

Containerized Database Indexing Service

Η παρούσα εργασία αποσκοπεί στην δημιουργία μίας υπηρεσίας ευρετηρίου βάσης δεδομένων η οποία θα φιλοξενείται μέσα σε έναν περιέκτη (container) και θα εξυπηρετεί πολλούς χρήστες ταυτόχρονα. Η εξυπηρέτηση των χρηστών θα γίνεται απομακρυσμένα σύμφωνα με το μοντέλο πελάτη-εξυπηρετητή (server-client). Αρχικά, θα εισάγουμε την έννοια της εικονικοποίησης και θα εξερευνήσουμε δύο βασικές εκφάνσεις της. Από τη μία θα εξετάσουμε τις εικονικές μηχανές και από την άλλη την τεχνολογία των περιεκτών. Ακόμη, θα κάνουμε μία σύγκριση μεταξύ των δύο. Στη συνέχεια, θα αναλύσουμε διεξοδικά την υπηρεσία ευρετηρίου που θα χαρακτηρίζει την παρούσα εργασία. Θα δούμε αναλυτικά τις δομές και τις λειτουργίες τους και θα κάνουμε αξιολόγηση της απόδοσης της υπηρεσίας σχετικά με τους χρόνους απόκρισης και το μέγεθος των δεδομένων. Τέλος, θα εξάγουμε κάποια συμπεράσματα για την υπηρεσία και θα προτείνουμε εναλλακτικούς τρόπους υλοποίησής της.This work aims to create a database indexing service hosted inside a container and serving multiple users at once. The customer service will be remote based on the client-server model. Initially, we will introduce the concept of virtualization and explore two key aspects of it. On the one hand we will look at virtual machines and on the other hand the technology of the containers. We will also make a comparison between the two. We will then thoroughly analyze the indexing service that characterizes this work. We will look closely at their structures and operations, and we will evaluate service performance on response times and data size. Finally, we will draw some conclusions about the service and propose alternative ways of implementing it