2005
Conventional data management occurs primarily in centralized servers or in well-interconnected distributed systems. These are removed from their end users, who interact with the systems mostly…
2004
The rapid adoption of XML as the standard for data representation and exchange foreshadows a massive increase in the amounts of XML data collected, maintained, and queried over the Internet or in…
In large statistical and scientific data management environments, where mediation architectures are used to integrate disparate and autonomous systems, a new problem - self-deadlock - may cause…
Query Personalization is the process of dynamically enhancing a query with related user preferences stored in a user profile with the aim of providing personalized answers. The underlying idea is…
Large-scale distributed environments, where each node is completely autonomous and offers services to its peers through external communication, pose significant challenges to query processing and…
As information becomes available in increasing amounts to a wide spectrum of users, the need for a shift towards a more user-centered information access paradigm arises. We develop a…
Twig queries represent the building blocks of declarative query languages over XML data. A twig query describes a complex traversal of the document graph and generates a set of element tuples based…
Searching a digital library is typically a tedious task. A system can improve information access by building on knowledge about a user acquired in a user profile in order to customize information…
The last decade has seen unprecedented advances in network and distributed-system technologies, which have opened up the way for the construction of global-scale systems based on completely new…
We present a technique that is based on volatile mapping objects and enables wrappers-based mediation architectures to describe bi-directional (read–write) interschema mappings of multiple,…
In this paper we present a distributed query framework suitable for use in federations of digital libraries (DL). Inspired by e-commerce technology, we recognize CPU-processing and queries (and…
2003
A system for the effective resource scheduling of composite multimedia objects involves a sequence packing formulation of the composite object scheduling problem and associated efficient algorithms…
The history of histograms is long and rich, full of detailed information in every step. It includes the course of histograms in di erent scienti c elds, the successes and failures of histograms in…
A group of senior database researchers gathers every few years to assess the state of database research and to point out problem areas that deserve additional focus. This report summarizes the…
A preliminary study of the issues surrounding a seach engine for Grid environments, GRISEN, that would enable the provision of a variety of Grid information services, such as locating useful…
Speculation is an every day phenomenon whereby one acts in anticipation of particular conditions that are likely to hold in the future. Computer science research has seen many successfull…
The need for approximations of information has become very critical in the recent past. From traditional query optimization to newer functionality like user feedback and knowledge discovery, data…
2002
Multimedia applications require a guaranteed level of service for accessing continuous-media data. To obtain such guarantees, the database server where the data are residing must employ an…
2000
Conventional histograms are `static' since they cannot be updated but only recalculated. In this paper, we introduce a `dynamic' version of V-optimal histograms, which is constructed and maintained…
1999
Answering queries approximately has recently been proposed as a way to reduce query response times in on-line decision support systems, when the precise answer is not necessary or early feedback is…
A range-sum query sums over all selected cells of an OLAP data cube where the selection is specified by ranges of contiguous values for each dimension. An efficient approach to process such queries…
The concept of two schemas being equivalent is fundamental to database design, schema integration, and data model translation. An important notion of schema equivalence, query equivalence, was…
Bitmap indexes are useful in processing complex queries in decision support systems, and they have been implemented in several commercial database systems. A key design parameter for bitmap indexes…
The NSF Invitational Workshop on Distributed Information, Computation, and Process Management for Scientific and Engineering Environments (DICPM) brought together domain specialists from…
It is almost twenty years after the 1st SSDBM was held in Berkeley (then called Workshop on Statistical Database Management). It is almost ten years after the first of a few workshops organized by…
This is probably the paper that opened the gates for several generic computer optimization techniques that were inspired by optimization processes found in nature. This one introduced Simulated…
1998
Scheduling algorithms for composite multimedia presentations need to ensure that the user-defined synchronization constraints for the various presentation components are met. This requirement gives…
In several working environments, production involves repeated executions of certain procedures. A workflow describes the individual tasks performed in these procedures and their interrelationships…
Multimedia applications require a guaranteed level of service for accessing Continuous Media (CM) data, such as video and audio. To obtain such guarantees, the database server whom the data is…
Bitmap indexing has been touted as a promising approach for processing complex adhoc queries in read-mostly environments, like those of decision support systems. Nevertheless, only few possible…
1997
There is often a need to get quick approximate answers from large databases. This leads to a need for data reduction. There are many different approaches to this problem, some of them not…
In most database systems, the values of many important run-time parameters of the system, the data, or the query are unknown at query optimization time. Parametric query optimization attempts to…
Scheduling query execution plans is a particularly complex problem in hierarchical parallel systems, where each site consists of a collection of local time-shared (e.g., CPU(s) or disk(s)) and…
The result size of a query that involves multiple attributes from the same relation depends on these attributes' joint data distribution, i.e., the frequencies of all combinations of attribute…
For the past few years, we have been involved in an effort to develop a Desktop Experiment Management Environment that many experimental scientists would like to have on their desk. The environment…
Despite much interest in the area of Scientific Database Systems [2, 11], a major problem that many experimental scientists are still facing today is that there are no adequate experiment…
The notion of when two schemas are equivalent is fundamental to database design, schema integration, and data model translation. An important notion of schema equivalence, query equivalence was…
A database system that provides independence between the query and physical structure of the database tables by captioning each database table with a partial query reflecting the contents of that…
1996
Human-computer interaction (HCI) is the study of how people design, implement, and use interactive computer systems and how computers affect individuals, organizations, and society. This…
Dynamic queries constitute a very powerful mechanism for information visualization; some universe of data is visualized, and this visualization is modified on-the-fly as users modify the range of…
The amount of information that is generated and becomes available in today's world is alarming. Large databases used to be available only in major corporations and organizations. Now the smallest…
Many commercial database systems use some form of statistics, typically histograms, to summarize the contents of relations and permit efficient estimation of required quantities. While there has…
