We compare two models used to compute the internal hydrodynamics of a gas centrifuge. The scoop action is taken into account through boundary conditions on the flow entering the bowl of the centrifuge in the first model, and through sinks and drag forces in the chambers of the centrifuge in the seco
Two experimental comparisons of relational and hierarchical database models
โ Scribed by Margaret Brosey; Ben Shneiderman
- Publisher
- Elsevier Science
- Year
- 1978
- Weight
- 676 KB
- Volume
- 10
- Category
- Article
- ISSN
- 0020-7373
No coin nor oath required. For personal study only.
โฆ Synopsis
The data model is a central feature which characterizes and distinguishes database management systems. This paper presents two experimental comparative studies of two prominent data models; the relational and hierarchical models. Comprehension, problem solving situation and memorization tasks were performed by undergraduate subjects. Significant effects were found for the data model, presentation order, subject background and tasks.
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