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Towards a Tribology Information System

Description: Abstract: A workshop was held in July 985 to address the needs for a computerized tribology information and data system, as well as possible implementation schemes. The meeting was sponsored by the American Society of Mechanical Engineers, Research Committee on Tribology, the Department of Energy, Energy Conservation and Utililation Technology Division, and the National Bureau of Standards. The views of a broad sector of industry, academia, and government were obtained over a four-week period through participation by about 60 individuals. Specific categories that were treated were design, numeric data, bibliography, research in progress, newsletter, and product directory. The principal discussion content and the recommendations in each subject category are summarized here. There was general agreement that a system of this type would be broadly useful to the engineering community for the purpose of design and materials selection, and for the research community as an important aid in information access and flow. The workshop recommendations detailed four phases of development, starting with a demonstration prototype system and concluding with a full-scale operating data and information base. Specific plans in each phase and for each subject area were developed and are presented here. While continual input will be sought from the technical community to refine those plans, it is hoped that immediate efforts can begin in at least some of the areas, and that system use will quickly develop to a significant level, both nationally and internationally.
Date: December 1987
Creator: Rumble, John R., Jr. & Sibley, Lewis
Partner: UNT Libraries Government Documents Department

TableMaker: An ad hoc Query Tool for Relational Databases

Description: This paper discusses an ad hoc query tool for relational databases. Most Web servers hosting biological data limit users to a defined set of search options and output formats that are short of the whole range of options available to users with direct database access. However, to make full use of the wealth of data in the database resource, it is desirable to have an intermediate solution that provides a broad range of flexible query and output options through a Web portal.
Date: July 2008
Creator: Lushbough, Carol; Duvick, Jon; Dong, Qunfeng; Jennewein, Douglas; Reynoldson, Joe & Brendel, Volker
Partner: UNT College of Arts and Sciences

The Composite OLAP-Object Data Model

Description: In this paper, we define an OLAP-Object model that combines the main characteristics of OLAP and Object data models in order to achieve their functionalities in a common framework. We classify three different object classes: primitive, regular and composite. Then, we define a query language which uses the path concept in order to facilitate data navigation and data manipulation. The main feature of the proposed language is an anchor. It allows us to fix dynamically an object class (primitive, regular or composite) along the paths over the OLAP-Object data model for expressing queries. The queries can be formulated on objects, composite objects and combination of both. The power of the proposed query language is investigated through multiple query examples. The semantic of different clauses and syntax of the proposed language are investigated.
Date: December 7, 2005
Creator: Pourabbas, Elaheh & Shoshani, Arie
Partner: UNT Libraries Government Documents Department

Data.gov

Description: This website contains information about the Data.gov project and resources for accessing federal datasets, including the ability to search for data, download datasets, and use related tools. It also includes links to other sites with open data.
Date: 2011~
Partner: UNT Libraries Government Documents Department

High Availability On-line Relational Databases for Accelerator Control and Operation

Description: The role that relational database (RDB) technology plays in accelerator control and operation continues to grow in such areas as electronic logbooks, machine parameter definitions, and facility infrastructure management. RDBs are increasingly relied upon to provide the official 'master' copy of these data. Whereas the services provided by the RDB have traditionally not been 'mission critical', the availability of modern RDB management systems is now equivalent to that of standard computer file-systems. RDBs can be relied on to supply pseudo real-time response to operator and machine physicist requests. This paper describes recent developments in the IRMIS RDB project. Generic lattice support has been added, serving as the driver for model-based machine control. Abstract physics name service and process variable introspection has been added. Specific emphasis has been placed both on providing fast response time to accelerator operators and modeling code requests, as well as high (24/7) availability of the RDB service.
Date: May 4, 2009
Creator: Dohan,D.; Dalesio, L. & Carcassi, G.
Partner: UNT Libraries Government Documents Department

Discover America's Cultural Heritage Collections on the Web

Description: This presentation discusses The Portal to Texas History and the University of North Texas (UNT) Digital Library collections. It also discusses the invisible internet, other Texas digital collections, other large digital collections, major digital collections in other states, subscription databases, and gives strategies for searching all of these databases.
Date: February 25, 2010
Creator: Belden, Dreanna
Partner: UNT Libraries

A Highly Fault-Tolerant Distributed Database System with Replicated Data

Description: Because of the high cost and impracticality of a high connectivity network, most recent research in transaction processing has focused on a distributed replicated database system. In such a system, multiple copies of a data item are created and stored at several sites in the network, so that the system is able to tolerate more crash and communication failures and attain higher data availability. However, the multiple copies also introduce a global inconsistency problem, especially in a partitioned network. In this dissertation a tree quorum algorithm is proposed to solve this problem, imposing a logical tree structure along with dynamic system reconfiguration on all the copies of each data item. The proposed algorithm can be viewed as a dynamic voting technique which, with the help of an appropriate concurrency control algorithm, exhibits the major advantages of quorum-based replica control algorithms and of the available copies algorithm, so that a single copy is read for a read operation and a quorum of copies is written for a write operation. In addition, read and write quorums are computed dynamically and independently. As a result expensive read operations, like those that require several copies of a data item to be read in most quorum schemes, are eliminated. Furthermore, the message costs of read and write operations are reduced by the use of smaller quorum sizes. Quorum sizes can be reduced to a constant in a lightly loaded system, and log n in a failure-free network, as well as [n +1/2] in a partitioned network in a heavily loaded system. On average, our algorithm requires fewer messages than the best known tree quorum algorithm, while still maintaining the same upper bound on quorum size. One-copy serializability is guaranteed with higher data availability and highest degree of fault tolerance (up to n - 1 site ...
Date: December 1994
Creator: Lin, Tsai S. (Tsai Shooumeei)
Partner: UNT Libraries

Text Mining for Automatic Image Tagging

Description: This paper introduces several extractive approaches for automatic image tagging, relying exclusively on information mined from texts. Through evaluations on two datasets, the authors show that their methods exceed competitive baselines by a large margin, and compare favorably with the state-of-the-art that uses both textual and image features.
Date: August 2010
Creator: Leong, Chee Wee; Mihalcea, Rada, 1974- & Hassan, Samer
Partner: UNT College of Engineering

A Unifying Version Model for Objects and Schema in Object-Oriented Database System

Description: There have been a number of different versioning models proposed. The research in this area can be divided into two categories: object versioning and schema versioning. In this dissertation, both problem domains are considered as a single unit. This dissertation describes a unifying version model (UVM) for maintaining changes to both objects and schema. UVM handles schema versioning operations by using object versioning techniques. The result is that the UVM allows the OODBMS to be much smaller than previous systems. Also, programmers need know only one set of versioning operations; thus, reducing the learning time by half. This dissertation shows that UVM is a simple but semantically sound and powerful version model for both objects and schema.
Date: August 1997
Creator: Shin, Dongil
Partner: UNT Libraries