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Recent world events have affected the rates at which the United States Army Reserve (USAR) recruits and retains enlisted members. As these rates fluctuate, it becomes difficult for the USAR to forecast its recruiting requirements. This thesis describes a statistical model and an associated software tool designed to provide precise forecasts of aggregate USAR enlisted personnel trends. In particular, the tool can assist in forecasting specific USAR enlisted end strength requirements using aggregate accession, retention and attrition rates. Entitled the Army Reserve Enlisted Aggregate Flow Model (AREAFM), the tool uses a Markov Growth Model and, for the purposes of this thesis, it is standardized using fiscal year 2001 (FY01) through FY03 data and validated with FY04 data. The AREAFM is intended for annual use in forecasting the number of enlisted accessions required to achieve USAR end strength. The model can also be used to evaluate how adjustments in accession, promotion and attrition rates, perhaps as the result of changes in USAR manpower policies or current events, might affect the assigned strength. / US Army Reserve (USAR) author.

The purpose of this thesis is to explore how innovative information technologies can facilitate rapid acquisition by using new online information technologies. In the past decade, many legislative and executive branch initiatives have paved the way for government disengagement and commercial engagement within the acquisition community. With new technology and the exponential amount of information now being infused electronically around the world, it is imperative that we take advantage of the tools which the government and private commercial industry have to offer. The vision, within the acquisition community, is for online ordering systems to facilitate streamlined commercial item acquisitions that reap the benefits of improved efficiency, reduced overall costs, and timeliness. This thesis focuses on new technology, the issues surrounding current processes, and the future of rapid online acquisition. / US Army (USA) author.

"The development and clinical adoption of more effective fixation devices for re-approximating and immobilizing the sternum after open-heart surgery to enable bony healing has been limited, in part, by the lack of in vitro test methods used to evaluate these devices which precisely emulate in vivo loading of the sternum. The present study is an initial effort to determine the loading parameters necessary to improve current in vitro and numerical test methods by characterizing the direction, magnitude, and distribution of loading along the sternotomy midline in vivo using a porcine model. Changes in forces incurred by death and embalming were also investigated to estimate the applicability of cadavers as chest models for sternal fixation. Two instrumented plating systems were used to measure the magnitude, direction, and distribution of forces across the bisected sternum in four pigs during spontaneous breathing, ventilated breathing, and coughing for four treatments; live, dead, embalmed, and refrigerated. Forces were highest in the lateral direction and highest at the xiphoid. An important finding was that the magnitude of the respiratory forces in all directions was smaller than anticipated from previous estimations, ranging from 0.37 N to 43.8 N. No significant differences in force were found between the four treatments, most likely due to the very small magnitude of the forces and high variability between animals. These results provide a first approximation of in vivo sternal forces and indicate that small cyclic fatigue loads should be applied for long periods of time, rather than large quasistatic loads, to best evaluate the next generation of sternal fixation devices. "

Le lois qui régissent le monde macroscopique ne s’appliquent pas toujours aux nanodomaines. Beaucoup de problèmes sont rencontrés lors de micromanipulations. Ces problèmes nécessitent d’être étudiés afin de pouvoir concevoir et produire des outils performants en micromécanique. A l’´echelle microscopique, les forces qui prédominent sont les forces de van derWaals, de capilarité et électrostatiques. Ce travail a pour thème les forces électrostatiques car elles sont les moins étudiées. Le but de ce projet est le développement d’un outil de simulation afin d’étudier les forces électrostatiques adhésives. Ce problème implique la compréhension de certains mécanismes comme l’électrification de contact. En pratique, le but sera de trouver des solutions pour contrôler les forces électrostatiques lors de la conception de micromanipulateurs et de développer des stratégies pour la micromanipulation. Ceci est possible grâce à un outil de simulation et à l’étude de la littérature. La particularité des simulations repose sur la prise en compte des paramètres de rugosité grâce à l’utilisation de la fonction fractale de Weierstrass-Mandelbrot. La première partie est dédiée à la revue de la littérature afin de comprendre les principes fondamentaux de l’électrostatique, les applications, et de répertorier les modèles de prédiction existants. Un outil de simulations est présenté et validé dans la seconde partie ainsi que le choix de la représentation fractale de la rugosité. Enfin, un banc de mesures de nano-forces est présenté qui permet de valider les resultats des simulations.

The van der Waals forces, which are forces between neutral atoms and molecules, play an important role in physics (e.g. in phase transitions), chemistry (e.g. in chemical reactions) and biology (e.g. in determining properties of DNA). These forces are of quantum nature and it is long being conjectured and experimentally verified that they have universal behaviour at large separations: they are attractive and decay as the inverse sixth power of the pairwise distance between the atoms or molecules. In this thesis we prove the van der Waals law under the technical condition that ionization energies (energies of removing electrons) of atoms are larger than electron affinities (energies released when adding electrons). This condition is well justified experimentally as can be seen from the table, \newline \begin{tabular}{|c|c|c|c|} \hline Atomic number & Element & Ionization energy (kcal/mol)& Electron affinity (kcal/mol) \\ \hline 1 & H & 313.5 & 17.3 \\ \hline 6 & C & 259.6 & 29 \\ \hline 8 & O & 314.0 & 34 \\ \hline 9 & F & 401.8 & 79.5 \\ \hline 16 & S & 238.9 & 47 \\ \hline 17 & Cl & 300.0 & 83.4 \\ \hline \end{tabular} \newline where we give ionization energies and electron affinities for a small sample of atoms, and is obvious from heuristic considerations (the attraction of an electron to a positive ion is much stronger than to a neutral atom), however it is not proved so far rigorously. We verify this condition for systems of hydrogen atoms. With an informal definition of the cohesive energy $W(y),\ y=(y_1,...,y_M)$ between $M$ atoms as the difference between the lowest (ground state) energy, $E(y)$, of the system of the atoms with their nuclei fixed at the positions $y_1,...,y_M$ and the sum, $\sum_{j=1}^M E_j$, of lowest (ground state) energies of the non-interacting atoms, we show that for $|y_i-y_j|,\ i,j \in \{1,...,M\}, i \neq j,$ large enough, $$W(y)=-\sum_{i<j}^{1,M} \frac{\sigma_{ij}}{|y_i-y_j|^6}+O(\sum_{i<j}^{1,M} \frac{1}{|y_i-y_j|^7})$$ where $\sigma_{ij}$ are in principle computable positive constants depending on the nature of the atoms $i$ and $j$.

The van der Waals forces, which are forces between neutral atoms and molecules, play an important role in physics (e.g. in phase transitions), chemistry (e.g. in chemical reactions) and biology (e.g. in determining properties of DNA). These forces are of quantum nature and it is long being conjectured and experimentally verified that they have universal behaviour at large separations: they are attractive and decay as the inverse sixth power of the pairwise distance between the atoms or molecules. In this thesis we prove the van der Waals law under the technical condition that ionization energies (energies of removing electrons) of atoms are larger than electron affinities (energies released when adding electrons). This condition is well justified experimentally as can be seen from the table, \newline \begin{tabular}{|c|c|c|c|} \hline Atomic number & Element & Ionization energy (kcal/mol)& Electron affinity (kcal/mol) \\ \hline 1 & H & 313.5 & 17.3 \\ \hline 6 & C & 259.6 & 29 \\ \hline 8 & O & 314.0 & 34 \\ \hline 9 & F & 401.8 & 79.5 \\ \hline 16 & S & 238.9 & 47 \\ \hline 17 & Cl & 300.0 & 83.4 \\ \hline \end{tabular} \newline where we give ionization energies and electron affinities for a small sample of atoms, and is obvious from heuristic considerations (the attraction of an electron to a positive ion is much stronger than to a neutral atom), however it is not proved so far rigorously. We verify this condition for systems of hydrogen atoms. With an informal definition of the cohesive energy $W(y),\ y=(y_1,...,y_M)$ between $M$ atoms as the difference between the lowest (ground state) energy, $E(y)$, of the system of the atoms with their nuclei fixed at the positions $y_1,...,y_M$ and the sum, $\sum_{j=1}^M E_j$, of lowest (ground state) energies of the non-interacting atoms, we show that for $|y_i-y_j|,\ i,j \in \{1,...,M\}, i \neq j,$ large enough, $$W(y)=-\sum_{i<j}^{1,M} \frac{\sigma_{ij}}{|y_i-y_j|^6}+O(\sum_{i<j}^{1,M} \frac{1}{|y_i-y_j|^7})$$ where $\sigma_{ij}$ are in principle computable positive constants depending on the nature of the atoms $i$ and $j$.

Thesis (Ph. D.)--University of Texas at Austin, 2002. / Vita. Includes bibliographical references. Available also from UMI Company.