Use of Respirometry to Determine the Effect of Nutrient Enhancement on JP-8 Biodegradability

The purpose of this study was to use respirometry to measure the impact of nutrient combinations or treatments on JP - 8 biodegradation under simulated fuel spill soil conditions. The study was designed observe one soil type at a constant fuel exposure level of 1% and a constant moisture of 60% of field capacity. Three experiments conducted were of two and three factor designs with potassium nitrate and sodium phosphate addition levels serving as two factors and fuel serving as a third factor in Experiments 1 and 2. Cumulative oxygen values obtained by the respirometer were assumed to be a direct indicator of JP-8 biodegradation. Therefore, cumulative oxygen values were used as the response variable for statistical analysis to determine the impact of nutrient enhancement on biodegradation 0fJP - 8.O2 consumption and CO2 production rate data were collected to ensure respiration activity levels were declining or stable to allow for cumulative oxygen data interpretation. Nutrient enhancement was found not to have a positive impact on biodegradation under these conditions. Additionally, losses due to degradation of the JP - 8 were found to be less than losses from volatilization

Multimedia and Audience: Implications for Executive Summaries

In an effort to put technical reports into a multimedia format, this thesis explored audience analysis and multimedia issues related to executive summaries. While multimedia has been shown to be effective at conveying complex information in certain environments, little research has been done to apply this technology to technical reporting. This thesis concentrates on the executive summary audience because the executive summary is the most read and most important section of a report. To analyze the audience, I conducted telephone interviews with report readers using an interview form I developed based on Mathes and Stevenson\u27s guidelines for conducting an audience analysis. I included a section to assess the readers\u27 perceptions of the usefulness of four forms of multimedia--sound, video, hypertext, and CD-ROM--for effectively retrieving information from an executive summary. The data results show on average a well educated, middle aged group of readers with considerable experience in their jobs. In the multimedia assessment, hypertext was rated the most useful at retrieving information from an executive summary, with video, CD-ROM, and sound following in that order. For report writers, then, the data helps to narrow down the type of information to include and what multimedia format to consider when preparing an executive summary

Estimation of the Captive-Carry Survival Function for the Advanced Medium Range Air-to-Air Missile (AMRAAM)

This thesis considers the problem of estimating the survival function of an item (probability that the item functions for a time greater than a given time t) from sampling data subject to partial right censoring (a portion of the items in the sampling data have not yet been observed to fail). Specifically the thesis describes several parametric and non-parametric statistical models that can be used when the sampling data is subject to partial right censoring. These models are applied to the case of estimating the captive-carry survival function of the AIM-120A Advanced Medium Range Air-to-Air Missile (AMRAAM)

Aggregating Organizational Performance Metrics Using the Analytic Hierarchy Process

Measurement provides factual information which is necessary for effective control of business processes. Implementing a Total Quality Management (TQM) philosophy is a common process in many organizations today. The United States Air Force is using the Malcolm Baldrige National Quality Award criteria to measure organizational performance in implementing the Quality Air Force (QAF) initiative. Unfortunately, the Baldrige-based unit self-assessment (USA) process is an inconsistent measure due to its subjectivity, and is also time consuming to use. This study determined that a new USA method based on the analytic hierarchy process (AHP) was not a significant improvement over the existing QAF-USA method. Specifically, this study developed a new USA scoring method by adapting the AHP to use existing QAF evaluation criteria. A group of 11 evaluators used this new AHP-USA method to score a portion of a USA report, and they also compared the AHP-USA method to the QAF-USA method to gauge its understandability, usability, believability and applicability. The resulting data was used to determine the overall feasibility and desirability of using the new method as a replacement for the QAF-USA method

Optimal Mixed-Norm Control Synthesis for Discrete-Time Linear Systems

A mixed-norm approach to control synthesis for discrete time linear systems is developed. Specifically, the problem of minimizing the H2 norm of a transfer function, subject to a combination of ℓ1 and-or H∞ norm constraints on dissimilar but related transfer functions is considered. The uniqueness of the optimal solution is shown, and numerical methods for approximating the optimal solution to within arbitrary accuracy are developed. These methods generally result in high order compensators which can not be implemented in most practical applications. In response to this, a numerical method is developed which solves for suboptimal solutions of a fixed, specifiable order. The method is packaged as a toolbox for the popular MATLAB software program. Several examples are developed which demonstrate potential applications for the mixed-norm method

Neutron Damage in Distributed Bragg Reflectors and Microcavity Lasers

Distributed Bragg Reflectors (DBRs) grown on a gallium-arsenide substrate for a solid state mirror and a vertical cavity surface emitting laser (VCSEL) were subjected to a neutron fluence to determine the sensitivity of the DBRs. The samples were irradiated at Ohio State University\u27s 500 kW research reactor. Relative and absolute reflectance measurements were taken before and after each irradiation over a spectral band of 530 880 µm. Relative reflectance measurements showed that the irradiation did not cause any spectral shift over seven decades of neutron fluences. The reflectivity of the DBRs decreased from their initial measurements after being irradiated. The reflectance decrease was correlated to the incident neutron fluence to determine a Messenger Spratt type of equation to predict the DBRs response. A radiation damage constant for the VCSEL and DBR mirror were determined to be 3.83x1013 [neutrons/cm2] and 2.19x1013 [neutrons/cm2] respectively utilizing a 1 MeV equivalent (Si) neutron fluence

Sub-Optimal Control of Rigid Spacecraft Reorientation Using Three Momentum Wheels

This thesis addresses sub-optimal employment of 3 momentum wheels for large angle reorientation of rigid spacecraft with minimal induced spacecraft motion during maneuvers. In addition to development of general theory for 3 wheel vehicles, simulation results for a vehicle using momentum wheels for secondary attitude control (GPS Block IIR) are compared to results for a vehicle using them for primary attitude control (the Hubble Space Telescope), to demonstrate practical applications and limitations. While the control laws were developed assuming no external perturbing torques on the vehicle, reorientation scenarios were run both in a torque free environment as well as an environment with simulated gravity gradient and solar pressure torques. The goal was primarily to show the growth of vehicle angular velocities and again demonstrate limitations of the derived control laws. The results indicate that for real spacecraft with limited wheel momentum storage capacities, there is a significant trade-off between maneuver times and required wheel torques, and that final state errors (angular velocities) increase with increasing wheel torques. Nonetheless, the simulations demonstrated that large angle maneuvers can be performed for both GPS Block lift and Hubble Space Telescope in reasonable times and with small angular velocities using the sub-optimal control law. However, gravity gradient and solar pressure torques tended to cause larger fluctuations in total angular momentum, angular velocities, and final state errors for the Hubble Space Telescope

Determining the Effects of Waste Coal Ash on Landfill Radon Levels

Coal contains trace amounts of the primary radionuclides 40K, and elements of the 4n (232Th), 4n+2 (238U), and 4n+3 (235U) series including 220Rn and 222Rn. Combustion of coal by electric power and heat plants result in concentration of noncombustible mineral matter, including most of the radionuclides, in the coal ash. The increased radiation due to the concentration of radionuclides is known as technologically enhanced natural radiation. The purpose of this research was to determine the effects of landfilled coal ash on one specific aspect of technologically enhanced natural radiation, radon levels. Soil samples were collected from the ash landfill at Wright Patterson AFB and from several background locations, analyzed using gamma spectroscopy, and the 226Ra activities compared. The landfill 226Ra activity (4.78 ± 1.58 pCi/g) was 2.95 times higher than background (1.62 ± 0.04 pCi/g). Estimated outdoor and indoor radon emanation at the landfill are predicted to be enhanced by the same factor compared to background. Additionally, the indoor radon concentration calculated in a hypothetical structure built on the landfill (11.48 pCi/l) was above the Environmental Protection Agency\u27s action level of 4.0 pCi/l

The Application of Hybridized Genetic Algorithms to the Protein Folding Problem

The protein folding problem consists of attempting to determine the native conformation of a protein given its primary structure. This study examines various methods of hybridizing a genetic algorithm implementation in order to minimize an energy function and predict the conformation (structure) of Met-enkephalin. Genetic Algorithms are semi-optimal algorithms designed to explore and exploit a search space. The genetic algorithm uses selection, recombination, and mutation operators on populations of strings which represent possible solutions to the given problem. One step in solving the protein folding problem is the design of efficient energy minimization techniques. A conjugate gradient minimization technique is described and tested with different replacement frequencies. Baidwinian, Lamarckian, and probabilistic Lamarckian evolution are all tested. Another extension of simple genetic algorithms can be accomplished with niching. Niching works by de-emphasizing solutions based on their proximity to other solutions in the space. Several variations of niching are tested. Experiments are conducted to determine the benefits of each hybridization technique versus each other and versus the genetic algorithm by itself. The experiments are geared toward trying to find the lowest possible energy and hence the minimum conformation of Met-enkephalin. In the experiments, probabilistic Lamarckian strategies were successful in achieving energies below that of the published minimum in QUANTA

The Dependence of the Time-Asymptotic Structure of 3-D Vortex Breakdown on Boundary and Initial Conditions

The three-dimensional, compressible Navier-Stokes equations are solved numerically to simulate vortex breakdown in tubes. Time integration is performed with an implicit Beam-Warming algorithm, which uses fourth-order compact operators to discretize spatial derivatives. Initial conditions are obtained by solving the steady, compressible, and axisymmetric form of the Navier-Stokes equations using Newton\u27s method. Stability of the axisymmetric initial conditions is assessed through 3-D time integration. Unique axisymmetric solutions at a Reynolds number of 250 lose stability to 3-D disturbances at a critical value of vortex strength, resulting in 3-D and time-periodic flow. Axisymmetric solutions at a Reynolds number of 1000 contain regions of nonuniqueness. Within this region, 3-D time integration reveals only unique solutions, with nonunique, axisymmetric initial conditions converging to a unique solution that is steady and axisymmetric. Past the primary limit point, which approximately identifies critical flow, the solutions bifurcate into 3-D periodic flows