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The Effects of Computer Performance Assessment on Student Scores in a Computer Applications Course (open access)

The Effects of Computer Performance Assessment on Student Scores in a Computer Applications Course

The goal of this study was to determine if performance-based tests should be routinely administered to students in computer application courses. The purpose was to determine the most appropriate mode of testing for individuals taking a computer applications course. The study is divided into areas of assessment, personality traits, and computer attitudes.
Date: July 1994
Creator: Casey, Sue Hartness
System: The UNT Digital Library
Spatiotemporal Properties of Coupled Nonlinear Oscillators (open access)

Spatiotemporal Properties of Coupled Nonlinear Oscillators

Spatiotemporal properties of classical coupled nonlinear oscillators are investigated in this thesis. Chapter 1 gives an introduction to nonlinear lattices and to the concept of breathers, that are spatially localized and temporally periodic excitation in nonlinear lattices. The concept of anti-continuous limit that provides the basic methodology in probing spatiotemporal breather properties is discussed. In Chapter 2, the general approach for finding exact breather solutions from the anti-continuous limit is examined, and the rotating wave approximation(RWA) is applied to probe the spatial structure of static breathers. Numerical evidence reveals that the RWA relates the spatial structure of stable multi-breathers to a single breather of the same frequency. Chapter 3 presents linear stability analysis of static breathers and gives a systematic way to construct mobile breathers. Formation and collision properties of this moving breathers are also studied. Chapter 4 discusses dynamics of kinks and anti-kinks in hydrogen-bonded chains in the context of two-component soliton model. From molecular dynamics simulations with finite temperature, it is observed that, in a real system (eg. ice), a pair of kink and anti-kink can evolve into a moving-breather-like excitation. Chapter 5 is devoted to the understand of the effects of disorder in the Holstein model. The …
Date: July 1996
Creator: Chen, Ding
System: The UNT Digital Library
A Machine Learning Method Suitable for Dynamic Domains (open access)

A Machine Learning Method Suitable for Dynamic Domains

The efficacy of a machine learning technique is domain dependent. Some machine learning techniques work very well for certain domains but are ill-suited for other domains. One area that is of real-world concern is the flexibility with which machine learning techniques can adapt to dynamic domains. Currently, there are no known reports of any system that can learn dynamic domains, short of starting over (i.e., re-running the program). Starting over is neither time nor cost efficient for real-world production environments. This dissertation studied a method, referred to as Experience Based Learning (EBL), that attempts to deal with conditions related to learning dynamic domains. EBL is an extension of Instance Based Learning methods. The hypothesis of the study related to this research was that the EBL method would automatically adjust to domain changes and still provide classification accuracy similar to methods that require starting over. To test this hypothesis, twelve widely studied machine learning datasets were used. A dynamic domain was simulated by presenting these datasets in an uninterrupted cycle of train, test, and retrain. The order of the twelve datasets and the order of records within each dataset were randomized to control for order biases in each of ten runs. …
Date: July 1996
Creator: Rowe, Michael C. (Michael Charles)
System: The UNT Digital Library