The electrodeposition of novel materials such as multilayer nanotubes for giant magneto resistance (GMR) applications and bismuth telluride nanotubes for thermoelectric applications are presented in this dissertation. The motivation for the multilayer electrodeposition is the investigation of giant magnetoresistance (GMR), a change in the material resistance in an applied magnetic field as a consequence of antiferromagnetic coupling. The nanowire high aspect ratio geometry allows the measurement of GMR with the current applied perpendicular to the plane (CPP) of the multilayers, which has been theoretically identified as being larger than the GMR in the (CIP) configuration (current in plane of multilayers). The current perpendicular to the plane giant magneto-resistance (CPP)-(GMR) effect makes multilayered nanowires of huge interest as magnetic sensor materials. Electrodeposition is the most efficient method for fabricating magnetic nanowires. In addition to the cost-effectiveness, electrodeposition is one of the few methods that can overcome the geometrical restrictions of inserting metals into very deep nanometric recesses, making it the favored method for nanowire and nanotube fabrication. In this dissertation, the quaternary CoNiFeCu alloy system was investigated in order to electrodeposit multilayered nanowires/nanotubes for GMR effect. Electrodeposited multilayer CoNiFeCu/Cu nanowires and nanotubes were fabricated by pulsed applied electric potential and their giant magnetoresistance (GMR) behavior characterized. The effect of electrolyte concentration on the GMR was investigated. The FeSO₄, CoSO₄ and NiSO₄ concentrations were varied to optimize the GMR and the saturation field of the multilayered nanowires. Nanolayer thicknesses were controlled and varied for commercially viable GMR results. Furthermore, the influence of electrolyte temperature on nanotube formation and the resulting GMR was explored. Micro fluidic magnetic nanoparticles sensors based on CoNiFeCu/Cu GMR nanowires were fabricated for the first time. The test results show that the sensors are highly sensitive to small nanoparticle concentrations. Employing the potentiostatic electrodeposition, nanotubes of bismuth-telluride (Bi₂Te₃) were obtained. The electrolyte concentration was varied and affected the nanotube formation and the resulting Seebeck coefficients.

Statistics show that a high percentage of road related accidents are due to factors that cause impaired driving. Since information extraction in driving is predominantly a visual task, visual distraction and its implications are therefore important safety issues. The main objective of this research is to study some of the implications of demands to humans attention and perception and how it affects performance of tasks such as driving. Specifically, the study aims to determine the changes that occur in the visual behavior of drivers with different levels of driving experience by tracking the movement of the eye; examine the effects of different levels of task complexity on visual fixation strategies and visual stimulus recognition; investigate the effects of secondary task on attentional and visual focus and its impact on driving performance; and evaluate the implications of the use of information technology device (cellular phone) while driving on road safety. Thirty-eight students participated in the study consisting of two experiments. In the first experiment, the participants performed two driving sessions while wearing a head mounted eye tracking device. The second experiment involved driving while engaging in a cellular phone conversation. Fixation location, frequency, duration and saccadic path, were used to analyze eye movements. The study shows that differences in visual behavior of drivers exist; wherein drivers with infrequent driving per week fixated more on the dashboard area than on the front view (F(3,26) = 3.53, p<0.05), in contrast to the driver with more frequent use of vehicle per week where higher fixations were recorded in the front/center view (F(3,26) = 4.26). The degree of visual distraction contributes to the deterioration of driving resulting to 55% more driving errors committed. Higher time where no fixation was detected was observed when driving with distraction (from 96% to 91% for drivers with less frequency of vehicle use and 55% to 44% for drivers with more frequent use of vehicle). The number of pre-identified errors committed increased from 64 to 81, due to the effect of visual tunneling. This research presents objective data that strengthens the argument on the detrimental effects of distraction in driving.

Due to the recent improvements in digital photography and storage capacity, storing large amounts of images has been made possible, and efficient means to retrieve images matching a users query are needed. Content-based Image Retrieval (CBIR) systems automatically extract image contents based on image features, i.e. color, texture, and shape. Relevance feedback methods are applied to CBIR to integrate users perceptions and reduce the gap between high-level image semantics and low-level image features. The precision of a CBIR system in retrieving semantically rich (complex) images is improved in this dissertation work by making advancements in three areas of a CBIR system: input, process, and output. The input of the system includes a mechanism that provides the user with required tools to build and modify her query through feedbacks. Users behavioral in CBIR environments are studied, and a new feedback methodology is presented to efficiently capture users image perceptions. The process element includes image learning and retrieval algorithms. A Long-term image retrieval algorithm (LTL), which learns image semantics from prior search results available in the systems transaction history, is developed using Factor Analysis. Another algorithm, a short-term learner (STL) that captures users image perceptions based on image features and users feedbacks in the on-going transaction, is developed based on Linear Discriminant Analysis. Then, a mechanism is introduced to integrate these two algorithms to one retrieval procedure. Finally, a retrieval strategy that includes learning and searching phases is defined for arranging images in the output of the system. The developed relevance feedback methodology proved to reduce the effect of human subjectivity in providing feedbacks for complex images. Retrieval algorithms were applied to images with different degrees of complexity. LTL is efficient in extracting the semantics of complex images that have a history in the system. STL is suitable for query and images that can be effectively represented by their image features. Therefore, the performance of the system in retrieving images with visual and conceptual complexities was improved when both algorithms were applied simultaneously. Finally, the strategy of retrieval phases demonstrated promising results when the query complexity increases.

Film cooling is one of the cooling systems investigated for the application to gas turbine blades. Gas turbines use film cooling in addition to turbulated internal cooling to protect the blades outer surface from hot gases. The present study concentrates on the experimental and numerical investigation of film cooling performance for a row of cylindrical holes in a modern turbine blade. The adiabatic film effectiveness and the heat transfer coefficient are determined experimentally on a flat plate downstream of a row of inclined different geometries hole exit by using a single test transient IR thermography technique. The focus of this investigation is to investigate advanced cooling hole geometries on film cooling heat transfer and cooling effectiveness over flat and turbine airfoil surfaces. Four test designs, crescent and converging slot, trench and cratered hole exits, are tested. Variations of these configurations are tested under two different test rigs. Results show that both the crescent and slot exits reduce the jet momentum at exit and also provide significantly higher film effectiveness with some increases in heat transfer coefficients. The trench where in the jets come in and spread evenly into a slot before exiting. An optimum trench depth exists at 0.75D as shallower and deeper trenches show worse performance. The cratered holes increase film effectiveness over the baseline case by about 50%. However, they do not provide significant lateral spreading as seen for trenched holes. Meanwhile, film cooling predictions are used to understand the mechanisms of the jets that exit these trenched holes and crater holes. The present work employs RSM (Reynolds stress transport model) for simulation of turbulent flows in film cooling and the simulation was run using FLUENT computer code. Comparisons are made with experimental data for the film effectiveness distributions. Results show that the film cooling jet exiting the trenched hole is more two-dimensional than the typical cylindrical holes and crater holes. Detailed flow structure visualization shows that the trench design counteracts the detrimental vorticity of the round hole flow, allowing it to remain attached to the surface.

Estimation of seasonal demand prior to an active demand season is essential in supply chain management. The business cycle of the seasonal demand is divided into two stages: stage-1, the slow-demand period, and stage-2, the peak-demand period. The focus here is to determine an appropriate demand forecast for the peak-demand period. In the first set of forecasting model, a standard gamma and an inverse gamma prior distribution are used to forecast demand. The parameters of the prior model are estimated and updated based on current observation using Bayesian technique. The forecasts are derived for both complete and incomplete datasets. The second set of forecast is derived by ARIMA method using Box-Jenkins approaches. A Bayesian ARIMA is proposed to forecast demand from incomplete dataset. A partial dataset of a seasonal product, collected from the US census bureau, is used in the models. Missing values in the dataset often arise in various situations. The models are extended to forecast demand from an incomplete dataset by the assumption that the original dataset contains missing values. The forecast by a multiplicative exponential smoothing model is used to compare all the forecast. The performances are tested by several error measures such as relative errors, mean absolute deviation, and tracking signals. A newsvendor inventory model with emergency procurement options and a periodic review model are studied to determine the procurement quantity and inventory costs. The inventory cost of each demand forecast relative to the cost of actual demand is used as the basis to choose an appropriate forecast for the dataset. This study improves the quality of demand forecasts and determines the best forecast. The result reveals that forecasting models using Bayesian ARIMA model and Bayesian probability models perform better. The flexibility in the Bayesian approaches allows wider variability in the model parameters helps to improve demand forecasts. These models are particularly useful when past demand information is incomplete or limited to few periods. Furthermore, it was found that improvements in demand forecasting can provide better cost reductions than relying on inventory models.

Trans aconitic acid (TAA) is the predominant organic acid in cane leaf matter (CLM) juice. Its concentration is three to six times higher than the level found in sugarcane stalks. The variation of composition in terms of total fermentable sugars (TFS), anions, and cations of the LCP85-384 sugarcane variety during 2003-2006 seasons, as well as the ripener (Polado-L®) effect were analyzed. TAA content ranged between 2.1-3.1 kg / t CLM. The TFS in CLM juice yielded a fermentation efficiency of 92%, four points lower than with sugar molasses. Liquid-liquid extraction (LLE), solid-liquid extraction and ion exchange were evaluated for the recovery of TAA from CLM stillage. Tributyl phosphate -dodecane, ethyl acetate and butanol were evaluated for LLE. Maximum TAA extraction yield (92 g/100 g) was observed on acidification of CLM stillage to pH 2.0 with 50 % (v/v) sulfuric acid at an organic/aqueous phase ratio (OA) of 3.5 with butanol as extractant. Tributyl phosphate-dodecane had a similar extraction yield as butanol; however, in this mixed solvent formation of third phase was observed. Ethyl acetate had the lowest extraction yield. The purity of TAA extract in butanol was 32 g/100 g DS. Butanol extract was esterified with either sulfuric acid or a cation exchange resin as catalyst to yield tributyl aconitate (TBA). Resin efficiency was affected by the impurities. The overall yield using sulfuric acid was 84 %. TBA was decolorized with powder activated carbon. The attempts to esterify TAA from spray dried CLM stillage were unsuccessful. The highest conversion yield was only 2.5 %. Dowex Optipore SD-2, a non-ionic adsorbent, showed the best results among the resins and adsorbents evaluated. TBA and two citrate esters were compared to di-isononyl phthalate (DINP) as plasticizers of polyvinyl chloride (PVC). Thermal and mechanical properties were similar to those observed with DINP. CLM and leaves together represent up to 50% of the total fiber of cane. An economic model estimated that processing whole sugarcane can be a profitable business if it is transported at distance of no more than 20 miles from the field to the mill.

Electrodeposited Au/CoAu multilayered nanowires are materials with alternating layers of Au and CoAu in a wire where the layer thickness and wire diameter are nanometer size. They can be used for different applications. For example, the wires may exhibit giant magnetoresistance (GMR), a change in the materials resistance with a magnetic field, having applications as a sensor material for microdevices. If Co is etched from CoAu nanowires, rough, porous gold nanostructures will be left behind, which could be used as novel catalysts. In this study, the electrodeposition of Au/CoAu multilayered nanowires and nanotubes in nanoporous templates was explored from a non-cyanide electrolyte. The multilayers were deposited with a pulse current control and the template pore size played an important role in determining whether nanowires or nanotubes were formed. The magnetic and magnetoresistive properties of Au/CoAu multilayered nanostructures were examined. Au/CoAu multilayered thin films exhibited both normal and inverse CIP GMR. After electrodeposition, the solid nanowires were released from the template and one component was electrochemically etched from the nanowires. The electrochemical etching conditions were predetermined by the investigation of electrochemical etching behavior of CoAu alloy and pure Co thin films. By precisely controlling the electrochemical etching potential and time, the surface area of the nanowires was enhanced. Nano-bamboo structures were created after partial etching and Au nanodisk structures were created after complete etching. Compared to conventional chemical etching, the anodization etching process presented here can be controlled to produce partially etched structures. The anodization process was monitored by two techniques. The current was recorded during etching and the total charge was proportional to the layer size. In addition, cyclic voltammetry (CV) was used as a way to observe the partial etching of the nanowires. In addition, the annealing post-treatment was tested to enhance the magnetoresistive properties of Au/CoAu multilayered nanostructures and to improve the quality of the multilayer interface by promoting phase segregation. Furthermore, hollow nano-bamboo structure and ordered nanorings with various aspect ratios were developed through the electrochemical etching of Au/CoAu nanotubes in a similar way. To the best of the authors knowledge, this has not been done before.

PURPOSE: This research was conducted to assess methods to manage the residue blanket to avoid open field burning in sugarcane. Experiments were conducted in the state of Louisiana to evaluate methods to asses and potentially reduce water quality issues. METHODS: Concentrations and frequencies of biological compost tea were sprayed on sugarcane combine-harvester residue blanket to increase degradation rate and reduce potential for runoff water to transport nutrients and sediments that may impair water bodies, while sustaining suitable sugarcane yield. Carbon dioxide evolution rate (mg CO2-C) and CO2 fluxes were measured in laboratory and in open field conditions; as an index to measure organic matter degradation. A runoff water novel collector was proposed to collect runoff water samples from sugarcane fields. RESULTS: Results demonstrate that carbon dioxide evolution rates (mg CO2-C gr-1DW h-1) were increased when applying compost tea to a shredded and non-shredded material under laboratory conditions. However, no significant differences were found among treatments. The highest degradation rate was found when applying compost tea to a dosage of 5.6 m 3 hectare-1 for a non-shredded material and 2.8 m 3 hectare-1 for shredded material. Open field evaluations demonstrated that soil carbon dioxide fluxes (µmol m2 s-1) as an indication of organic matter degradation; were significantly increased when applying compost tea to sugarcane residue left in field. The most practical degradation rate may be achieved when applying a dosage of 2.8 m 3 hectare-1 two times during the spring-time. The findings indicate that applications of biological compost tea and slow release nitrogen fertilizer could enhance nitrogen transport to water bodies. It may also indicate the opportunity to reduce supplemental inorganic nitrogen to sugarcane fields. CONCLUSION: Results partially support previous research indicating that combine-harvester leaves a residue blanket on soil, which may reduce sugar yields in subsequent crops; since sugarcane residue management treatments were not significantly different (alpha = 0.05) with respect to yield during 2006 and 2007 harvest periods. Burning the residue also led to higher runoff water (175.2 m3 ha-1), high concentrations of suspended solids (93.4 mg L -1) and up to 6.93 mg L -1 of PO4 in runoff water.

A highly sensitive miniaturized biomass transducer is necessary for continuous and reliable monitoring of the microalgal biomass in a computer controlled, automated microalgal bioreactor. Previous known methods to determine microalgal biomass applicable in these bioreactors are based on single wavelength turbidimetric or fluorescence. The objectives of this research were to (1) determine the light absorption characteristics of some commercially applicable microalgae in the electromagnetic wavelength range of 200-800 nm (2) design and construct a new miniaturized biomass transducer (3) process the transducer output to correlate with the biomass. Wavelength sensitivity analysis was conducted on the commercially important microalgal species - Nannochloropsis oculata, Isochrysis galbana and Thalassiosira weissflogii, for a growth range of 0-500 mg dry wt L-1. Maximum absorptions were found at UVC, followed by blue and red regions of the electromagnetic spectrum. A new biomass transducer based on UVC measurement was designed and constructed. The measurements were processed for signal conditioning and higher sensitivity. It was followed by further processing in a central control computer to filter the noise present in UVC measurement. A statistical relationship was developed for signal processing between the individual variables and a new model for the calibration curve was proposed. The new biomass transducer was tested using the developed signal processing algorithm and the calibration with individual microalgal samples as well as the mixed samples independent of calibration curve. The tested results gave an average error < 10% relative to the mean of actual readings.

A moderately-rapid assessment tool was developed to analyze the waterless desiccation compost toilet investigated in a rural Mexican setting. Over 100 social factors were identified along with the applicable technical factors that influenced the low acceptability of the toilets. A 4-point rating scale was developed to increase the ability and speed of analyzing both the social and technical data. The treatment process was an alkaline-desiccation process with mean pH values of 8.2 ± sd 1.1 and water content of 18.3% ± sd 9.9, which resulted in mean fecal coliform values of 15.0 MPN/g ± sd 31.8, drastically lower than the 1000 MPN/g United States Environmental Protection Agency (USEPA) limit. Alkalinity, not pH, was determined to be the limiting factor in some waste samples, resulting in the need to dilute the waste with local soils. Designs were developed to reduce the unnecessarily long detention times between 0.75 to 4.4 years and improve other features, especially additive use and waste handling. Solvita® test kits were used to assess compost characteristics. Modifications, made to kit procedures to enable their use, included adjusting pH values and extending the pre-test acclimation period. With low macro-nutrient concentrations, a mean carbon/nitrogen ratio of 14.0 ± sd 6.1, and a mean volatile solids value of 15.9 ± sd 6.9 indicative of low organic matter, the finished waste had limited agricultural value, however, the treatment process did efficiently remove nitrogen in many samples and eliminate the pathogens in all of them. Mean Specific Oxygen Uptake Rate (SOUR) values of 1.4 ± sd 1.1 mg O2 / gram total solids were substantially close with the USEPA standard of 1.5. The SOUR on a volatile solids basis was not applicable. A socially and technically useful ASH/VS (inorganic/organic solids) ratio was discovered with mean concentration values of 6.8 ± sd 4.2 with most values falling within an easily explainable socially-valuable ten-point scale. The introduction of two other dry batch composting toilets created a competitive situation in the community where comparative analysis was being performed with the preferred pour-flush water toilet. If water shortages continue, the desiccation toilets acceptability may increase again.