Three dimensional pulsatile blood flow CFD simulations in geometrically genuine normal and non-normal (aneurysm) human neck-head vascular systems nominally spanning the aortic arch to the circle of Willis has been performed and studied. CT scans of the human aortic arch and the carotid arteries were interpreted to obtain geometric data defining the boundary for a vascular CFD simulation. This was accomplished by reconstructing the surface from the anatomical slices and by imposing pertinent boundary conditions at the various artery termini. Following automated formation of a non-conformal CFD mesh, steady and unsteady laminar and low turbulent simulations were performed both for the normal and aneurysm models. Atherosclerosis and atherosclerotic induced aneurysms can occur in the ascending aorta. The results showed marked differences in the flow dynamics for the two models. Secondary flow is induced in both of the models due to the curvature of the aortic arch which is distorted in three dimensions. Counter clockwise rotating vortex formation was seen at the aneurysm segment in the ascending aorta for the aneurysm model which was absent for the normal case. The effect of the aneurysm bulge was seen in regions proximal to it at peak reverse flow causing secondary flow. These secondary aortic blood flows are though to have an effect on the wall shear stress distribution. Maximum pressure regions for the aneurysm were observed at regions distal to it indicating the possible location for rupture. Wall shear force (WSF) values for the normal case at the aortic bend were low indicating the possible reason for the formation of the aneurysm in the first place. The WSF values at the aneurysm segment for the aneurysm case were also low supporting the low shear stress induced atherosclerotic aneurysms theory. These results may act as a precursor for a multiscale Large eddy simulation model (LES) for pulsatile blood flow eliminating the need for a priori definition of the flow as laminar or turbulent.

This dissertation deals with an important problem in Data Mining and Knowledge Discovery (DM & KD), and Information Technology (IT) in general. It addresses the problem of efficiently learning monotone Boolean functions via membership queries to oracles. The monotone Boolean function can be thought of as a phenomenon, such as breast cancer or a computer crash, together with a set of predictor variables. The oracle can be thought of as an entity that knows the underlying monotone Boolean function, and provides a Boolean response to each query. In practice, it may take the shape of a human expert, or it may be the outcome of performing tasks such as running experiments or searching large databases. Monotone Boolean functions have a general knowledge representation power and are inherently frequent in applications. A key goal of this dissertation is to demonstrate the wide spectrum of important real-life applications that can be analyzed by using the new proposed computational approaches. The applications of breast cancer diagnosis, computer crashing, college acceptance policies, and record linkage in databases are here used to demonstrate this point and illustrate the algorithmic details. Monotone Boolean functions have the added benefit of being intuitive. This property is perhaps the most important in learning environments, especially when human interaction is involved, since people tend to make better use of knowledge they can easily interpret, understand, validate, and remember. The main goal of this dissertation is to design new algorithms that can minimize the average number of queries used to completely reconstruct monotone Boolean functions defined on a finite set of vectors V = {0,1}^n. The optimal query selections are found via a recursive algorithm in exponential time (in the size of V). The optimality conditions are then summarized in the simple form of evaluative criteria, which are near optimal and only take polynomial time to compute. Extensive unbiased empirical results show that the evaluative criterion approach is far superior to any of the existing methods. In fact, the reduction in average number of queries increases exponentially with the number of variables n, and faster than exponentially with the oracle's error rate.

In recent years, biofiltration technology has been used at numerous locations worldwide as an air pollution control technology for treating gases contaminated with low concentrations of biodegradable volatile organic compounds (VOCs). At the same time, there have been many reports in the literature of contaminant emissions from biofilters during transient loading conditions. There is currently a need to develop methods for controlling such emissions. Periodically operated bioreactors have been used successfully in treatment of wastewater and soils for several decades to mitigate the effects of uncontrolled unsteady-state loading on waste treatment systems. Such operating strategies have only recently been applied to biofilters treating gas-phase contaminants. Research described herein compared contaminant removal efficiency in biofilters subjected to periodic operating strategies to that of a conventional continuously loaded biofilter. Methy ethyl ketone (MEK), a compound that is regulated as a hazardous air pollutant (HAP) under the 1990 Clean Air Act amendments, was used as a model compound. Experiments were conducted to assess the ability of biofilters to remove MEK during quasi-steady state conditions (i.e., ¡°normal¡± operation) as well as during transient periods of elevated contaminant loading (i.e., ¡°shock loading¡± conditions). An influent MEK concentration of 106 ppmv was used for normal loading experiments while a concentration of five times that (530 ppmv) was applied during one-hour shock loading experiments. Shock loading experiments were conducted to evaluate both active and passive control techniques. Results reported herein demonstrate that controlled periodic operating strategies can enhance contaminant removal of MEK during transient periods of elevated contaminant load. Shock loading experiments testing active control strategies resulted in MEK removal efficiencies greater than 95% for the periodic systems, while ranging from 55 to 70% for the continuously loaded biofilter. Removal efficiencies for the periodically operated systems dropped to less than 30% during experiments conducted to assess biofilter response to uncontrolled contaminant loading in the absence of an active control strategy. Thus, while periodic operation coupled with an active control strategy can improve biofilter performance during at least some transient loading conditions, there is a clear need for adequate control systems if such an operating strategy is adopted.

This research consists of two projects concerned with handwheel-valve operations. The purposes of poject-1 were to: (1) compare accepted reference contraction (RC) procedures (also known as maximum voluntary contraction or MVC) in the literature for the anterior deltoid and trapezius muscles to newly proposed RC procedures; and (2) introduce an innovative ergonomic design of a valve wrench and compare it to conventional valve-opening methods. The proposed RC procedure for the anterior deltoids involved positioning the shoulders at 90o flexion with fixed straps wrapped around the distal end of the upper arm, on which participants exerted upward isometric forces. The proposed RC procedure for the trapezii involved performing isometric lateral raises at 100o shoulder abduction against fixed chains. Results showed that the proposed RC produced 58% and 46% higher EMG levels for the right and left anterior deltoids, respectively, than the accepted RC. Also, the proposed RC for the right and left trapezii produced 68% higher EMG levels than the accepted RC. In conclusion, both proposed RC procedures for the anterior deltoids and trapezii muscles allowed the production of higher EMG activities than the accepted RC procedures in the literature. Four valve-opening methods were evaluated, including using bare hands (BH), conventional wrench-restricted (CW-R, assumes the presence of obstructions), conventional wrench-unrestricted (CW-U, assumes no obstructions), and modified wrench (MW). These methods were tested on a medium-sized gate valve at two torque settings (15 Nm and 30 Nm). The methods were compared to each other, in terms of the time to open the valve, perceived physical exertion (Borg-scale), and electromyography (EMG) activities of the right and left anterior deltoids, trapezii, latissimi dorsi, and erector spinae muscles. The method that was associated with the lowest overall EMG activities was CW-R, followed by BH, MW, and finally CW-U. According to the Borg-scale, the method that was perceived to be the least physically demanding was MW (3.0), followed by CW-U (3.5), CW-R (4.4), and finally BH (4.8). The method that required the least time to fully open the valve was MW (23.1 s), followed by CW-U (25.6 s), BH (39.8 s), and finally CW-R (88.5 s). This project designed an ergonomic wrench that is more efficient in opening valves and less physically strenuous than conventional valve-opening methods. The purpose of project-2 was twofold: (1) to determine operators maximum torque production capabilities on a handwheel at various heights (knee, elbow, shoulder, and overhead levels) and angles (0o, 45o, and 90o); and (2) to investigate the shoulder and trunk muscle activities associated with the different height-angle combinations. Measurements of maximal isometric torque exertions and EMG activities of the same muscles as in project-1 were recorded at each height-angle combination. The average maximum torque exertions ranged between 51.6 Nm (found at overhead 0o) and 74.9 Nm (found at overhead 45o) depending on the height and angle of the handwheel. Considering both the EMG results and the maximal torque exertions, the optimum height and angle of a handwheel appeared to be at shoulder 0o. At this height and angle, the reaction forces from the torque exertions were not concentrated at any one muscle, but rather the load was distributed on different muscles. Seven of the eight muscles were active at or close to their lowest EMG activities. Also, at this handwheel position, participants were capable of producing fairly large torques (65.2 Nm). Using the maximum torque data and Potvins Equation, this study also developed graphs of maximum acceptable torque limits for valve systems as a function of duty cycle (DC: the percentage of time an individual is engaged in effort) and the handwheel height and angle. The findings from this project may contribute to the development of design standards for handwheel-valve systems (i.e. standard handwheel height, angle, and torque).

Recent literature studies have demonstrated depletion in natural resources; therefore, making resources needed for the pavement industry is more costly. There is a need to minimize cost and to try to reduce the depletion of natural resources. While the recycling of asphalt shingles is beneficial in reducing the consumption of virgin materials, pavement performance should not be compromised. One major concern with recycled asphalt shingles (RAS) relates to the variability in the properties of the recycled materials originating from different sources. In addition, the rheological properties of RAS have not been evaluated as well as its influence on the virgin binder when used in asphalt mixtures. Therefore, the objectives of this study were to characterize the rheological properties and molecular fractions of RAS materials sampled from different sources around the country. In addition, the influence of RAS on the Superpave Performance Grade (PG) of the binder was investigated. Results of the experimental program indicated that the asphalt cement (AC) content in tear-off shingles was consistent among different RAS sources across the country. However, AC content in manufacturer waste shingles was noticeably lower than in tear-off shingles. Furthermore, all extracted RAS binders were graded as PG 118 or higher using the Superpave binder specification system but the low temperature grade was not measurable due to the high stiffness of the binder. This stiff behavior is due to the binder used in shingle manufacturing, which is an air-blown asphalt binder with stiff characteristics and low elongation properties. Results showed that at a RAS content of up to 5%, the high temperature grade of the blends was increased by one to seven grades and the low temperature grade was increased by one grade. The use of binder blending charts is recommended to account for the influence of RAS in the mix design. At a RAS content of 10%, the binder blends did not pass the Superpave criterion at low temperature.

In the United States, nearly 9 million people, 3.0% of the population, live in areas subject to the 1% annual chance (100-yr) coastal flood hazard. New construction and substantial improvements in coastal high hazard areas require structures to be elevated above the design flood elevation (DFE), without the use of fill (Bellomo et al. 1999). Building code requirements for flood elevation are linked to the National Flood Insurance Program (NFIP) insurance policies, and represent the minimum requirement for building elevation. Current elevation procedures are limited to the 100-year base flood elevation with minimal guidance beyond the 100-year elevation in many locations, which may be of interest to those designing critical facilities and buildings with a longer design life (e.g. institutional buildings). Additional code-plus resources exist to provide best available practices for practitioners; however, gaps still exist that may lead to lower design elevations than warranted for a particular risk level. In an effort to provide guidance for practitioners, this thesis presents a methodology to address existing gaps in combination in the context of current best practices. A short case study to demonstrate the proposed methodology in comparison to code and best practices is provided. To provide guidance for longer return period flood events, this thesis uses stillwater elevations (SWEL) from flood insurance studies (FIS) to extrapolate flood elevations associated with longer return periods. FIS data are fit using the Huff-Angel and SRCC regression models, resulting in an equation to be used for extrapolating new flood elevations. The results of are evaluated using R2 values, differences in projected elevations and known elevations for the same return period, and normalized data for the 100-year SWELs. The result of this work is not intended to become integrated into current code or policy regulations in the United States, but rather to provide generalized guidance to aid practitioners in decision making by consolidating current code, best practices, and characteristics of the changing coastal environment.

Field trials of photocatalytic pavements were recently initiated and are presently being considered by many states (e.g., Virginia, Texas, New York, and Missouri). Results from this study originate from the countrys first air-purifying asphalt and concrete photocatalytic pavements, constructed on Dec. 20, 2010. The test area is a pavement site located on the LSU campus. The objective of the study is to validate field photocatalytic degradation of NOx in a field environment by measuring the day to day accumulation of the oxidized byproduct; nitrate salts. The mass of nitrates, produced by the real life photocatalytic pavement, were measured. The measurement was then correlated to the same mass of nitrates as recovered from laboratory samples with recorded NOx reductions in accordance to the Japanese Industrial Standards. This paper presents a nitrate sampling procedure, to be administered in the field, without the need for core sampling. Based on the results of the experimental program, the proposed method, quantify photocatalytic efficiency through nitrate measurements, was successful. There is evidence that photocatalytic degradation of nitrogen oxide was occurring in the treated section when compared to the control. The photocatalytic process was highly active during the first four days, followed by a decrease in the degradation rate of NOx. The decreased degradation activity might be caused by a continuous decrease in ambient NOx levels that occurred during the collection. Full regeneration of photocatalytic activity occurs in the field through a self-cleaning process during a rain event. Six months of traffic and in-service operating conditions proved to have negligible effects on the durability of the photocatalytic coating, when comparing the mass of nitrates recovered to just after installation. In addition, there was a good agreement between NO removal efficiency measured in the field after one day of nitrate accumulation with the laboratory experiment at the same level of relative humidity.

Reducing heating and cooling systems loads in buildings is a cost effective way to decrease energy consumption in residential houses. This reduction can be achieved in many ways including proper insulation of the building envelope. In recent years, considerable attention was given to the use of radiant reflective insulating barriers. Over the past years, reflective barrier insulation companies nationwide have experienced significant growth resulting in an industry average growth rate of 26.8%. This significant growth is expected to continue as a result of increased cooling demands and pressure from the energy sector and the economy. Growth is also predicted to be prevalent amongst the southern regions of the United States in efforts to reduce high cooling energy costs, which are expected to prevail. This significant growth has not been felt by the radiant barrier industry in Louisiana. This is mainly due to the lack of knowledge and amount of research available in quantifying radiant barriers thermal effectiveness for hot and humid climatic conditions widely encountered in the State. In order to improve the competitiveness of the reflective insulation industry, the primary goal of this research is to develop a simple estimating tool that may be used by homeowners, state agencies, and contractors to assess the effectiveness and economic benefits of radiant barrier insulation systems under the climatic conditions encountered in United States. Current research achieved this objective by adopting a multi‐dimensional research approach that developed this estimating tool over three main phases and then combined results of these phases to provide an overall assessment tool for this technology. In the first phase, the energy saving benefits of radiant barrier was quantified experimentally for the climatic conditions and construction practices prevalent in United States. A transient heat transfer finite element (FE) model was developed to predict the ceiling heat gain or loss through the attic space in residential buildings and to accurately estimate savings in cooling and heating loads produced by the radiant barrier application. Validity of the models was established by comparing their prediction with experimental data. In the second phase, economic effectiveness of radiant barrier technology was evaluated. In the third phase, development of the estimating tool and dissemination of the results was achieved. Results showed that radiant barrier can reduce heat flux transferred from roof to the condition space significantly.

Assessing an affected area immediately after a severe natural hazard event and saving the resulting data are vitally important in any effort to reduce future economic losses from natural hazards. These data are used as a record of buildings performance and as a major component for statistical analysis and damage modeling studies. Since these data are used as input for these studies, the data must be assessed and collected in a scientific and standardized way. Despite this requirement, neither a systematic damage assessment process nor a standardized data collection protocol is currently available in the United States to ensure that the necessary, correct, and accurate damage and attribute data are collected, assessed, managed, and saved for hurricane events. In cases where these data are actually collected and assessed, they are lost soon after the event, rather than kept to longitudinally assess building performance in severe natural hazard events over the long term. To make building damage assessment more effective and more accurate, a systematic process to standardize assessment data is needed. Additionally, to ensure that data are correctly assessed and collected, a standard protocol implemented in damage assessment activities is vitally needed. This study presents a proposed hurricane damage assessment process for residential buildings subjected to combined hurricane wind and flood loads, as well as a protocol that can be implemented into the process to standardize data collection and damage assessment. The proposed process and protocol represent the first comprehensive building damage data assessment and collection process in the literature. Implementation of this process will aid in improving building data collection and assessment after hurricane events, which will result in improved data for a better understanding of building performance. Long-term implementation of this process will provide insight about the performance of multiple buildings subjected to various levels of hazard. This knowledge will facilitate reassessment of the level of loss experienced in hurricane events, and will provide needed data for the development of enhanced performance-based design standards and building codes, which will lead to more reliable building performance.

The Abstract was sent to Ms. McKenzie as an attachment to an e-mail