Databases and Information Systems Commons^™

Fault Tolerance In A Very Large Database System: A Strawman Analysis, Amit P. Sheth

Kno.e.sis Publications

A simple model is used to study the effect of fault-tolerance techniques and system design on system availability. A generic multiprocessor architecture is used that can be configured in different ways to study the effect of system architectures. Important parameters studied are different system architectures and hardware fault-tolerance techniques, mean time to failure of basic components, database size and distribution, interconnect capacity, etc. Quantitative analysis compares the relative effect of different parameter values. Results show that the effect of different parameter values on system availability can be very significant. System architecture, use of hardware fault tolerance (particularly mirroring), and data …

A Tool For Integrating Conceptual Schemas And User Views, Amit P. Sheth, James A. Larson, Aloysius Cornelio, Shamkant B. Navathe

Kno.e.sis Publications

An interactive tool has been developed to assist database designers and administrators (DDA) in integrating schemas. It collects the information required for integration from a DDA, performs essential bookkeeping, and integrates schemas according to the semantics provided. The authors present the capabilities of this tool by discussing the integration methodology and the user interface of the tool.

The Computer As A Collection Management Tool, Suzanne B. Mclaren, Hugh H. Genoways, Duane A. Schlitter

University of Nebraska State Museum: Mammalogy Papers

Since the mid-1960s, discussion of computer use for information retrieval in museum collections has usually focused on research potential. Much attention has been given to the idea of networking and the ability to access data across great distances. However, the potential for collection management usage has also proven to be a legitimate rationale for computerization. Numerous aspects of collection management are discussed for which the computer may be employed. Topics include creating cross-reference files, updating taxonomic and geographic information, pinpointing mismatched specimens, locating lost and uncataloged material, controlling loan procedures, producing accession files for insurance purposes, curating all or part …

An Analysis Of The Effect Of Network Load And Topology On The Performance Of Concurrency Control Algorithm In Distributed Database Systems, Anoop Singhal, Amit P. Sheth, Ming T. Liu

Kno.e.sis Publications

Earlier studies in the performance analysis of concurrency control algorithms in distributed database systems (DDBS) have assumed that the message transmission time between any two nodes of a network is constant. Hence they disregard the effect of communication subnet related parameters such as network traffic, network topology, the capacity of transmission channels and the size of messages transmitted. In this paper an analytical model is used to estimate the delays in transmission channels for a DDBS in a long haul network. The analysis shows that the constant transmission time assumption cannot be justified in many cases and that response time …

Decide : How Much Superphosphate, G A. Robertson, J. W. Bowden, N. J. Halse

Journal of the Department of Agriculture, Western Australia, Series 4

* A 400 per cent increase in ihe price of superphosphate has reduced the economic optimum rates of super for crops and pastures in 1975.

* Many factors, both biological and economic, must be taken into account in determining the rate of superphosphate to apply.

• DECIDE, a model developed by CSIRO and the Department of Agriculture, provides a formal system in which all these factors can be considered.

• DECIDE is based on the results of all research on superphosphate carried out in Western Australia. However, each farmer's own knowledge of his farm, the soils, crops and animals is …

Grade Herd Recording, 1963-64, Maurice C. Cullity

Journal of the Department of Agriculture, Western Australia, Series 4

A review of Grade Herd Recording during the 1963-64 season.

THERE was a substantial increase in the number of cows which were recorded in 1963-64 compared with 1962-63 (23,520 and 22,635 respectively).

This season's figure represents 20.4 per cent, of all cows in the dairying districts.

The number of cows which completed lactation and therefore whose yields were included in the averages, rose from 17,258 to 19,011.

Grade Herd Recording : 1962-63, Maurice C. Cullity

Journal of the Department of Agriculture, Western Australia, Series 4

A poor season coupled with a 16 per cent, increase in the number of cows tested during 1962-63 led to a drop in the average yields of cows in the Grade Herd Recording Scheme.