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Full-Text Articles in Applied Mathematics
Modeling Radiation Effectiveness For Inactivation Of Bacillus Spores, Emily A. Knight
Modeling Radiation Effectiveness For Inactivation Of Bacillus Spores, Emily A. Knight
Theses and Dissertations
This research models and analyzes the inactivation of Bacillus spores following a radiation exposure and the process enacted by the Bacillus spore to repair the resulting damage. Irradiation of a spore and the medium surrounding the spore induces chemical reactions that produce reactive oxygen species (ROS). This research will consider the reaction- diffusion of these ROS throughout the spore. These ROS can react with the spore's DNA and enzymes to degrade them to such an extent that the DNA cannot be repaired or replicated, thus causing spore death. In order to survive a dose of radiation, a spore must repair …
Testing The Adequacy Of A Semi-Markov Process, Richard S. Seymour
Testing The Adequacy Of A Semi-Markov Process, Richard S. Seymour
Theses and Dissertations
Due to the versatility of its structure, the semi-Markov process is a powerful modeling tool used to describe complex systems. Though similar in structure to continuous time Markov chains, semi-Markov processes allow for any transition time distribution which enables these processes to t a wider range of problems than the continuous time Markov chain. While semi-Markov processes have been applied in fields as varied as biostatistics and finance, there does not exist a theoretically-based, systematic method to determine if a semi-Markov process accurately fits the underlying data used to create the model. In fields such as regression and analysis of …
Accuracy Of Time Phasing Aircraft Development Using The Continuous Distribution Function, Gregory E. Brown
Accuracy Of Time Phasing Aircraft Development Using The Continuous Distribution Function, Gregory E. Brown
Theses and Dissertations
Early research on time phasing primarily focuses on the theoretical foundation for applying the continuous distribution function, or S-curve, to model the distribution of development expenditures. Minimal methodology is provided for estimating the S-curve's parameter values. Brown, White, and Gallagher (2002) resolve this shortcoming through regression analysis, but their methodology has not been widely adopted by aircraft cost analysts, as it is judged as overly broad and not specific to aircraft. Instead, analysts commonly apply the 60/40 rule of thumb to aircraft development, assuming 60 percent expenditures at 50 percent schedule. It is currently unknown if the 60/40 heuristic accurately …
Symmetry Groups For Linear Programming Relaxations Of Orthogonal Array Problems, David M. Arquette
Symmetry Groups For Linear Programming Relaxations Of Orthogonal Array Problems, David M. Arquette
Theses and Dissertations
Integer linear programs arise in many situations, and solving such problems can be computationally demanding. One way to solve them more efficiently is by exploiting the symmetry within their formulation. This paper proves that the symmetry group for the linear programming relaxation of 2-level orthogonal array problems of strength 2 is a particular semidirect product.
Examining The Return On Investment Of Test And Evaluation, Nathan C. Smith
Examining The Return On Investment Of Test And Evaluation, Nathan C. Smith
Theses and Dissertations
This research examined the return on investment of Department of Defense test and evaluation. The thesis analyzed the return on investment of the cost avoidance achieved if an issue discovered late in the program had been discovered and corrected during developmental test and evaluation. The methodology utilized two case study examples from the Joint Primary Training Aircraft System to calculate the potential cost avoidance and the potential return on investment if the program had discovered and corrected the issues during developmental test and evaluation. The result of one case was a 9,260% return on investment. The other case results ranged …