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There currently exists no reliable, non-destructive method for measuring stress in railroads and other similar structures without the need for a calibration measurement. Major limitations which have hindered previous techniques include sensitivity to boundary conditions, insensitivity to stress, and intolerance for material and geometry uncertainty. In this work, a technique is developed which seeks to solve these challenges by extracting the spectrum relation, or dispersion curve, of a waveguide from dispersive wave propagation meaasurements. The technique is based on spectral analysis of waves in structures modeled as beams, and as such is based on relatively low frequency vibrations, as opposed to other techniques which use nonlinear elastic modeling of structures at ultrasonic frequencies. The major contribution of this work is the development of a frequency-domain based signal processing technique which is capable of compensating for the dispersive, long wavelength reflections which have limited the ability of previous techniques to go low enough in frequency to achieve high stress sensitivity. By compensating for reflections, the present work is able to automate the process of analyzing wave propagation signals such that the entire dispersion curve can be extracted, enabling the identification of various parameters including stress, stiffness, density, and other material and geometry properties. This in turn enables measuring stress, performing model-updating for material and geometry uncertainty, and being indifferent to boundary conditions. The theory and algorithmic implementation is presented, along with simulations and experimental validation on a rectangular beam.

In aviation applications, navigation integrity is paramount. Integrity of GPS systems is well established with set standards. Vision-based navigation systems have been found to be an adequate substitute for GPS when it is unavailable but are unlikely to be utilized until there is a measure for system integrity. Work has been done to detect the effect of a single measurement pair being corrupted with a bias; however, the measurement geometry varies greatly with the environment. The environment could be sparse in visual features to track, or the environment could be rich with features. With more features, there is a greater probability of having multiple corrupted measurements. It is essential that multiple corrupt measurements are detected and excluded to assure the integrity and reliability of the system. In addition, misalignment errors in the camera system results in systematic errors that are undetectable by current methods. This dissertation focuses on understanding the existing integrity monitoring methods and using them for the detection of multiple errors in vision-based navigation systems, as well as, developing a technique for detecting systematic errors due to camera misalignment and scaling. These methods are developed analytically and verified by using simulations. These simulations serve to demonstrate the usefulness of these methods in achieving the goal of this research to further the area of integrity monitoring for vision systems, so it could eventually be used as a trusted system and as a back-up for GPS navigation.

In aviation applications, navigation integrity is paramount. Integrity of GPS systems is well established with set standards. Vision based navigation systems have been found to be an adequate substitute for GPS, when it is unavailable but are unlikely to be utilized until there is a measure for system integrity. Work has been done to detect the effect of a single measurement pair being corrupted with a bias; however, the measurement geometry varies greatly with the environment. The environment could be sparse in visual features to track, or the environment could be rich with features. With more features, there is a greater probability of having multiple corrupted measurements. It is essential that multiple corrupt measurements are detected and excluded to assure the integrity and reliability of the system. This thesis focuses on understanding the existing integrity monitoring methods and using them for the detection of multiple errors in vision-based navigation systems. The current techniques are found to have the ability to detect single and multiple errors, but they cannot isolate them. This thesis develops an algorithm with the ability to isolate multiple erroneous measurements adding to the capabilities of existing integrity monitoring fault detection and isolation techniques.

Scene model based segmentation of video into foreground and background structure has long been an important and ongoing research topic in image processing and computer vision. Segmentation of complex video scenes into binary foreground/background label images is often the first step in a wide range of video processing applications. Examples of common applications include surveillance, Traffic Monitoring, People Tracking, Activity Recognition, and Event Detection.

A need exists to develop manufacturing technologies for armor alloys that can replace risk-sensitive welding. Armor materials have poor formability at room temperature and are prone to cracking even at modest bend radii. An Induction assisted bending process has been successfully performed using titanium alloy Ti-6Al-4V. The main objective of this work was to develop optimized procedures for induction assisted hot bending of titanium and steel armor. The response of several armor alloys to high temperature straining and the effect of induction bending on their mechanical properties and microstructure were evaluated. A methodology for characterization and testing of armor materials which supports the development of induction bending procedures was also developed. The results of this research have expanded the elevated temperature data for several grades of alloy Ti6-4 and for three armor steel alloys. The latter included single grades of rolled homogeneous armor (RHA), high hard armor (HHA) and Armox 440 steel.Induction bent plates of grade 5 Ti6-4 were characterized using optical and scanning electron microscopy. Utilizing a mandrel radius of 50 mm, crack free induction bends were made in ½” thick grade 5 plates at temperatures as low as 427 °C. Using a 12.5 mm mandrel radius resulted in cracking at bending temperatures below 621 °C. The surface roughness of the plates may have provided stress concentration sites for crack initiation. Also, voids were discovered near the surface and in front of crack tips using optical and scanning electron microscopy. These voids provide evidence for a possible crack propagation mechanism. The depth of the cracks and the void locations were utilized to calculate the strain associated with these defects. This was used to generate a strain vs. deformation temperature plot that can be utilized by manufactures as a process development and control tool.Heating of Armox 440 below the A1 temperature resulted in over tempering and a significant softening with a drop in hardness to 28 HRc from 47.6 HRc in the as-delivered condition. Straining of this still below the A1 temperature at 700 °C resulted in significant loss of room temperature tensile strength. These results illustrate the need for a post bend heat treatment of Armox 440 to restore the mechanical properties. A methodology for characterization and testing of armor materials has been established, which supports the development of induction bending procedures that can be applied to other materials. This methodology includes: 1) hot ductility testing to determine the optimum temperature range for induction bending; 2) metallurgical characterization and hardness testing to evaluate the material response to elevated temperature exposure; and 3) high temperature straining followed by room temperature tensile testing and hardness testing to evaluate the effect of induction bending on mechanical properties. The test results are utilized to generate an optimal strain vs. temperature process control window for induction bending of the tested armor alloy.

In many sports, including golf, the body is called upon to produce movement of the hands or feet at the highest possible velocities to best complete a task. Proximal to distal sequencing has been acknowledged by multiple researchers as a means to achieve these velocities. When using segmental angular velocity components, proximal to distal sequencing has been termed the “kinematic sequence”. Researchers have found that amateur golfers tended to exhibit a more inefficient energy transfer from segment to segment than professional golfers. Physical limitations have been suggested as a source of inefficiency in the kinematic sequence. In the golf swing, a large torque occurs between the moving upper body and the relatively stationary pelvis, which can create a significant amount of stress on the lower back. The lower back is the most common injury site among golfers. Based on the frequency of lower back injuries and the number of people that play golf, conservatively four million people in the United States are affected by lower back injuries.Physicians, therapists, athletic trainers, and coaches have incorporated aspects of trunk control and core strength training in almost every sport in the hope of preventing or treating injuries and improving performance of the upper and lower extremity. While trunk control and core strength training are popular, at this point it is only speculation as to whether core stability, core strength, and core endurance are important to the production of the proper kinematic sequence, greater clubhead velocity, and presence of lower transverse lumbar spine torques.Eleven male subjects with a golf handicap index of seven or less participated in this correlational laboratory study. Consisting of two parts, the first part of testing used passive optical motion capture techniques to record the subjects’ golf swings as they hit golf balls with their own driver. The main outcome measures were the number of swings out of 10 that exhibited the proper kinematic sequence, average of the peak clubhead velocity over the 10 swings, and the average of peak transverse lumbar spine torque during those 10 swings. In the second part of testing, subjects performed six lumbopelvic tests specifically targeting core stability, strength, or endurance. Linear regression analysis was used to determine the association between the results of the lumbopelvic tests and the swing outcome measures.None of the six lumbopelvic tests revealed a significant correlation with proper kinematic sequence production or peak transverse lumbar spine torque. However, peak clubhead angular velocity did significantly correlate with a core stability test measuring pelvic positional control (R=0.72, p=0.012). A sample size estimation analysis for future studies is presented based on the results of this pilot study. Future work should continue to analyze the relationship between core function and golfer performance and injury risk variables. The collective knowledge gained from this and subsequent studies may come in the form of improved training programs that result in performance improvement and reduced injury potential for the golfing population.

The majority of work in this Thesis will investigate the use of expanded beds for different separations in the field of Biotechnology and consider how best to utilise expanded beds most efficiently and effectively. The aims of the project were to develop a novel affinity purification from initial method scouting to pilot plant expanded bed level, and then to consider and develop a more effective and faster method of monitoring and control of and expanded bed than traditionally used off-line manual techniques. A protocol was successfully developed for the purification of yeast alcohol dehydrogenase (ADH) from unclarified homogenate using immobilised metal ion affinity chromatography in a STREAMLINETM expanded bed adsorption system, demonstrating high levels of recovery of the target protein. A novel system of breakthrough monitoring and control was developed using a combination of in-bed sampling and a rapid stopped flow analysis system. This enabled accurate control of product breakthrough at different levels when purifying ADH from crude homogenate feedstock. In addition this monitoring technique demonstrated variation in matrix utilisation with axial position, providing scope for the final section of work noted here. In-bed sampling also allowed the physical properties of the matrix to be studied and experimental radial and axial particle size distributions during expansion were obtained, along with the development of a method for measuring voidage in short sections of the bed under expansion. Finally, matrix utilisation was studied using segregated beds of varying particle size ranges in order to establish dynamic binding capacities and hence matrix productivity. Determination of dynamic capacities at different breakthrough levels for beds consisting of smallest and largest particles showed that, while smaller particles have more than double the total binding capacity of larger particles, at low breakthrough levels the larger particles have a higher dymanic binding capacity and hence a higher productivity.