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Barreto-Munoz, Armando. "Multi-Sensor Vegetation Index and Land Surface Phenology Earth Science Data Records in Support of Global Change Studies: Data Quality Challenges and Data Explorer System". Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/301661.
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Synoptic global remote sensing provides a multitude of land surface state variables. The continuous collection, for more than 30 years, of global observations has contributed to the creation of a unique and long term satellite imagery archive from different sensors. These records have become an invaluable source of data for many environmental and global change related studies. The problem, however, is that they are not readily available for use in research and application environment and require multiple preprocessing. Here, we looked at the daily global data records from the Advanced Very High Resolution Radiometer (AVHRR) and the Moderate Resolution Imaging Spectroradiometer (MODIS), two of the most widely available and used datasets, with the objective of assessing their quality and suitability to support studies dealing with global trends and changes at the land surface. Findings show that clouds are the major data quality inhibitors, and that the MODIS cloud masking algorithm performs better than the AVHRR. Results show that areas of high ecological importance, like the Amazon, are most prone to lack of data due to cloud cover and aerosols leading to extended periods of time with no useful data, sometimes months. While the standard approach to these challenges has been compositing of daily images to generate a representative map over a preset time periods, our results indicate that preset compositing is not the optimal solution and a hybrid location dependent method that preserves the high frequency of these observations over the areas where clouds are not as prevalent works better. Using this data quality information the Vegetation Index and Phenology (VIP) Laboratory at The University of Arizona produced over 30 years of seamless sensor independent record of vegetation indices and land surface phenology metrics. These data records consist of 0.05-degree resolution global images for daily, 7-days, 15-days and monthly temporal frequency. These sort of remote sensing based products are normally made available through the internet by large data centers, like the Land Processes Distributed Active Archive Center (LP DAAC), however, in this project an online tool, the VIP Data Explorer, was developed to support the visualization, exploration, and distribution of these Earth Science Data Records (ESDRs) keeping it closer to the data generation center which provides a more active data support and distribution model. This web application has made it possible for users to explore and evaluate the products suite before download and use.
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Bon, Tom A., i Henry L. Kucera. "Agricultural and Biosystems Engineering Capstone Course Evolution at North Dakota State University". American Society of Agricultural and Biological Engineers, 2005. https://hdl.handle.net/10365/31010.
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The approach to the department's capstone design course has changed considerably since the 1960s. The general evolution of the course has proceeded from extended laboratory exercises to individuals working on self-defined projects to team-based projects. Interactions between the capstone course and other courses have been attempted with varying success. This paper presents the development of the NDSU Agricultural and Biosystems Engineering Department' s capstone course and thoughts on possible future modifications to the course.Agricultural and Biosystems Engineering
College of Graduate and Interdisciplinary Studies
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Sherman, Adrian Tyrone. "Occurrence and distribution of fecal indicator bacteria with respect to urban and rural land uses". Click HERE to connect, 2009. http://digital.library.okstate.edu/etd/Sherman_okstate_0664M_10169.pdf.
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Tejral, Ronald. "Impact of dam and reservoir parameters on peak breach discharge predictions for two models". Click HERE to connect, 2009. http://digital.library.okstate.edu/etd/Tejral_okstate_0664M_10170.pdf.
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Wilding, Kristen Michelle. "Engineering Cell-Free Biosystems for On-Site Production and Rapid Design of Next-Generation Therapeutics". BYU ScholarsArchive, 2018. https://scholarsarchive.byu.edu/etd/7713.
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While protein therapeutics are indispensable in the treatment of a variety of diseases, including cancer, rheumatoid arthritis, and diabetes, key limitations including short half-lives, high immunogenicity, protein instability, and centralized production complicate long-term use and on-demand production. Site-specific polymer conjugation provides a method for mitigating these challenges while minimizing negative impacts on protein activity. However, the location-dependent effects of polymer conjugation are not well understood. Cell-free protein synthesis provides direct access to the synthesis environment and rapid synthesis times, enabling rapid evaluation of multiple conjugation sites on a target protein. Here, work is presented towards developing cell-free protein synthesis as a platform for both design and on-demand production of next generation polymer-protein therapeutics, including (1) eliminating endotoxin contamination in cell-free reagents for simplified therapeutic preparation, (2) improving shelf-stability of cell-free reagents via lyophilization for on-demand production, (3) coupling coarse-grain simulation with high-throughput cell-free protein synthesis to enable rapid identification of optimal polymer conjugation sites, and (4) optimizing cell-free protein synthesis for production of therapeutic proteins
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Gendrault, Yves. "Structuration d'un flot de conception pour la biologie synthétique". Phd thesis, Université de Strasbourg, 2013. http://tel.archives-ouvertes.fr/tel-01015878.
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La biologie synthétique est une science issue du rapprochement entre les biotechnologies et les sciences pour l'ingénieur. Elle consiste à créer de nouveaux systèmes biologiques par une combinaison rationnelle d'éléments biologiques standardisés, découplés de leur contexte naturel. L'environnement, l'agroalimentaire et la santé figurent parmi ses principaux domaines d'application. Cette thèse s'est focalisée sur les aspects liés à la conception ex-vivo de ces biosystèmes artificiels. A partir des analogies réalisées entre les processus biologiques et certaines fonctions électroniques, l'accent a été mis sur la réutilisation et l'adaptation des outils de conception numériques, supportant l'approche de conception " top-down ". Ainsi, une adaptation complète des méthodes de CAO de la microélectronique a été mise en place pour la biologie synthétique. Dans cette optique, les mécanismes biologiques élémentaires ont été modélisés sous plusieurs niveaux d'abstraction, allant de l'abstraction numérique à des modèles flux de signal et des modèles conservatifs. Des modèles en logique floue ont aussi été développés pour faire le lien entre ces niveaux d'abstraction. Ces différents modèles ont été implémentés avec deux langages de description matérielle et ont été validés sur la base de résultats expérimentaux de biosystèmes artificiels parmi les plus avancés. Parallèlement au travail de formalisation des modèles destinés au flot de conception, leur amélioration a aussi été étudiée : la modélisation des interactions entre plusieurs molécules a été rendue plus réaliste et le développement de modèles de bruits biologiques a également été intégré au processus. Cette thèse constitue donc une contribution importante dans la structuration et l'automatisation d'étapes de conception pour les biosystèmes synthétiques. Elle a permis de tracer les contours d'un flot de conception complet, adapté de la microélectronique, et d'en mettre en évidence les intérêts.
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Edward, Drabold T. "BIOLOGICAL DESIGN OF CONTINUOUS MICROALGAE SYSTEMS: A REVIEW". Ohio University Honors Tutorial College / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors161891425130329.
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Drabold, Edward T. "BIOLOGICAL DESIGN OF CONTINUOUS MICROALGAE SYSTEMS: A REVIEW". Ohio University Honors Tutorial College / OhioLINK, 2021. http://rave.ohiolink.edu/etdc/view?acc_num=ouhonors161891425130329.
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Kacheris, William, i William Kacheris. "A Novel Approach for Calculating the Feasibility of Urban Agriculture using an Enhanced Hydroponic System". Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/620674.
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With a continued worldwide trend in population shift from rural to urban areas predicted to increase, new approaches to agricultural production must be considered and implemented. Little academic interest has been applied to determining economically viable urban agriculture crop production sites for business investment. A feasibility model to aid investors in selecting appropriate sites for the development of urban agriculture food production within population centers was created. Lettuce crop trials were performed from August 2015 to December 2015 at the University of Arizona Controlled Environment Agriculture Center to validate the productivity of a unique high density hydroponic system designed for the rooftop environment. The feasibility model is based on this system and with a minimal number of inputs, ranging from size of growing space to growing media costs, determines a wide range of useful outputs. These outputs include crop productivity within the facility, material inputs and a cost breakdown of starting a new agricultural venture. The model utilizes multiple sheets within one excel document to give the user a clear and organized financial perspective of a hypothetical growing operation in the main sheet. With this model, investors into urban agriculture will have a means to gain an objective view of financial considerations before substantial investment is completed.
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Rodriguez, Jesus, i Jesus Rodriguez. "Downscaling Modis Evapotranspiration via Cokriging in Wellton-Mohawk Irrigation and Drainage District, Yuma, AZ". Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/621782.
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Evapotranspiration (ET) is a key parameter for irrigation planning and management, and it is a crucial factor for water conservation practices considering the challenges associated with agricultural water availability. Field ET determination is the most accurate, but remains to be expensive and limited in scope. On the other hand, remote sensing is becoming an alternative tool for the estimation of ET. Operational ET algorithms, like the Moderate Resolution Imaging Spectroradiometer (MODIS)-based ET, are now successful at generating ET estimates globally at 1km resolution, however their intent is not management of agriculture irrigation. This research was done to develop an integrated method for downscaling MODIS ET appropriate for farm-level applications using geostatistical and remote sensing techniques. The proposed methodology was applied in the Wellton-Mohawk Irrigation and Drainage District of Yuma, Arizona. In a first effort, ET data was downscaled from standard 1-km-MODIS to a medium 250-m-spatial resolution via cokriging using Land Surface Temperature and Enhanced Vegetation Index as covariates. Results showed consistent downscaled ET with a variance greater than the variance of the coarse scale input and nearly similar mean values. This 250m product can serve larger irrigation districts in developed countries, where plot size is fairly large and regular. However, the size and shapes of most farms in developing countries makes the 250m ET challenging. For this reason, the second part of this work was done to downscale global scale 1km ET to 30m farm level application for irrigation use. This approach involved the generation of daily vegetation indices (VI) at 30m in order to support the downscaling of MODIS 1km ET. Landsat and MODIS reflectances were combined with the Spatial and Temporal Adaptive Reflectance Fusion Model (STARFM) algorithm and the resulting VI data was used as a covariate to downscale ET with the cokriging approach. The results showed that the MODIS ET data seriously underestimates ET over irrigated areas. To correct this problem the MODIS data was then adjusted using field measured values to make it useful for operational purposes. The proposed geospatial method was applied to different growth stages of cotton and results were validated with actual ET from The Arizona Meteorological Network (AZMET) and published consumptive use of water for the area. The adjusted downscaled ET was comparable to these two published data (maximum error of 33%). This methodology is a practical alternative in areas where there is no ancillary data to estimate ET and it is expected to help in the planning of irrigation agriculture that will lead to improved agricultural productivity and irrigation efficiency.
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Valdivia, Lefort Patricio. "Design of an Efficient Harvester and Dewater Mechanism for Microalgae". Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/306344.
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Microalgae have now been widely considered as a promising bio-energy feedstock. The current microalgae harvesting methods used, such as centrifugation, sedimentation and flocculation, have been shown to be effective but are costly, representing between 35 % to 50 % of the total production cost. The aims of this study were: (1) to investigate the effectiveness of two electrocoagulation processes, electroflocculation and electroflotation, as algae pre-harvesting processes; and (2) to design, test and optimize a cost-effective and efficient filtration-based harvesting mechanism for micrioalgae. The principal results of the study showed that: (1) The mean final concentration for electroflocculation of 17.94 gL⁻¹ significantly exceeded (p = 0.0416) that for electroflotation of 9.51 gL⁻¹, indicating electroflocculation to be the more effective process; (2) Microscope images of the algae showed that, for the level of power applied (1 A, 40 V max), electrocoagulation did not appear to have produced any effect on the algae that was significantly different from that by centrifugation and that neither method appeared to have caused any significant cell wall damage or rupture; (3) The most effective configuration for the harvester prototype -- resulting in higher throughput rate (0.303 gh⁻¹), higher efficiency (233.33 gL⁻¹), as well as a lower energy consumption (143.46 kWhm⁻³) -- corresponded with higher concentration of the incoming biomass (21.5 gL⁻¹), lower belt velocity (0.05 ms⁻¹), higher inclination angle (25°) and lower pressure (0 Psi); and (4) The total energy consumption for the harvester prototype, when combined with a preceding pre-harvesting process, of 4.95 kWhm⁻³ was comparable to those reported by others for filtration-based harvesting. The new efficient harvesting mechanism proposed showed significant potential in successfully reducing algae production cost and make biofuels from microalgae economically feasible in the mid to long term in view of the prototype having achieved high output biomass concentration, low energy consumption per unit volume, high throughput rate, and facility of implementation.
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Liu, Xiang. "Design of a Modified Shipping Container as Modular Unit for the Minimally Structured & Modular Vertical Farm". Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/347073.
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The specific aim of this study was to advance the development of the Minimally Structured & Modular Vertical Farm (MSM-VF), an original concept developed at The University of Arizona, by designing a specific modular unit made of a transparent-walled modified standard shipping container for use in climate locations represented by Los Angeles and New York City. The conclusions of the study included: (1) A workable range of temperatures (15 to 30°C) for cultivating tomato in Los Angeles and New York City could be achieved in a transparent-walled MSM-VF shipping-container modular unit by using a cover material of low density polyethylene (LDPE) and a heating, ventilating and air conditioning (HVAC) system with an airspeed of 2 m/s, inlet angle at 60° and outlet position located at the top of the back wall; (2) A workable range of temperatures (15 to 27°C) for cultivating lettuce in Los Angeles and New York City could be achieved by using a cover material of LDPE and an HVAC system with an air speed of 4m/s, inlet angle at 60° and outlet position located at the bottom of the back wall; (3) The annual energy demands of the plastic-walled MSM-VF shipping-container modular unit were far less than those for the opaque-walled control plant-factory unit in all cases, except in the one case of growing tomato in New York City. Still, in this one exception, the annual energy demand of growing tomato in New York City in the plastic-walled MSM-VF shipping-container modular unit of 557.65 kWh/m² (versus 325.34 kWh/m² for the opaque-walled control plant-factory unit) was significantly lower than that of 711.91 kWh/m², which was the average for 164 greenhouses occupying a total of 16444 m² operated by the Cornell University Agricultural Experiment Station (CUAES) in the state of New York (CUAES Greenhouses); and, (4) The annual energy demands of the plastic-walled MSM-VF shipping-container modular unit were either significantly lower or for one case approximately the same (773.84 kWh/m²) as that of the 711.91 kWh/m² for the New York greenhouses. By contrast, the annual energy demands of the opaque-walled control plant-factory unit significantly exceeded that of the 711.91 kWh/m² for the New York greenhouses by 170% for Los Angeles and by 126% for New York City, both for growing lettuce. The foregoing results provided significant and reasonable basis for the practicability of Minimally Structured & Modular Vertical Farms made of plastic-walled shipping-container modular units in Los Angeles and New York City as well as in many other mega-cities around the world with similar climates.
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Livingston, Peter. "Management of the Schmutzdecke Layer of a Slow Sand Filter". Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/293439.
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Slow sand filters (SSF) have been used to treat surface water to drinking water standards for over a century. Today many cities, including London still treat surface waters to drinking water standards, however because there are viruses that are not efficiently removed by a slow sand filter and are not killed by chlorine, communities have turned to the use of micro filtration and/or reverse osmosis to provide safe drinking water. These technologies are much more efficient if organics are removed and turbidity reduced to less than 1 Nephelometric Turbidity Units (NTU). The greenhouse industry is another potential user of slow sand filters. They are not able to recycle irrigation drainage water without it being treated to reduce bacteria, virus, and fungi. The objective of this research was to develop management strategies for SSF that specifically meet the needs of entities using SSF for pretreatment of potable water or use in a greenhouse. This data was used to test a scour system that resulted in scouring 80 percent of the organic layer in the filter and suspending the solids for 40 minutes. A conceptual design was done for a full scale SSF that took advantage of the scour and suspension data to clean the SSF at the end of a run cycle. SSF were able to consistently produce water with a turbidity less than 1 (NTU) and with the infiltration capacity of 0.27 m³m⁻². For greenhouse effluent a 1,000 square meter greenhouse that is discharging 3,600 L d⁻¹ of drainage water would require a 12.6 m² SSF, and the SSF for the community requiring treatment of 4.7 million liters per day of raw water was 730 m². The innovative cleaning system based on an air/water jet was developed to clean the SSF. Experiments were run to determine the amount of time that the solids were suspended and a scour system developed to exceed these times. The entire time for cleaning and recovery of the SSF was an average of 118 minutes for the greenhouse system and 170 minutes for the SSF serving a small community.
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He, Shiwei. "Hydrodynamic Optimization of the AirAccordion Photobioreactor for Microalgae Production". Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/613515.
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Algae are a prolific source of biochemicals with economic importance, including nutraceuticals, biofuels, animal feed, etc. The general aim of this study was to establish how the hydrodynamic conditions generated within specific types or designs of photobioreactors determine their respective algae growth. The specific objectives of this study were: (1) To determine and compare key hydrodynamic parameters in the Air Accordion photobioreactor and the conventional bubble column, including Residence Time, Vessel Dispersion Number, Bodenstein Number, Mixing Time and oxygen liquid mass transfer coefficient (kla); and, (2) To test how differences in the hydrodynamic conditions would result in significant difference in growths of the green alga Scenedesmus obliquuus between the photobioreactors. The results of the study showed that: (1) The Residence Time of 566 s for the Air Accordion significantly exceeded by 28% that of 444 s for the bubble column, signifying greater liquid mixing in the Air Accordion; (2) The Vessel Dispersion Number for the Air Accordion of 0.168 significantly exceeded that for the bubble column of 0.166, indicating greater degree of mixing in the Air Accordion than in the bubble column; (3) The Mixing Time in both the Air Accordion and the bubble column declined as the air flow rate increased, indicating that the tracer ions in both photobioreactors mixed more quickly. For each of the flow rates tested, however, the mixing time for the bubble column significantly exceeded that for the Air Accordion, indicating that liquid mixing in the Air Accordion occured significantly quicker than in the bubble column. At 1.0 LPM, the bubble column's Mixing Time of 10 s exceeded by 25% that of the Air Accordion of 8 s; (4) The oxygen liquid mass transfer coefficients in both photobioreactors increased as the air flow rate increased, indicating that the transfer of oxygen from the air bubbles into the liquid within the photobioreactors gained efficiency. For each of the air flow rates tested, however, the oxygen liquid mass transfer coefficient for the Air Accordion significantly exceeded that for the bubble column, indicating a significantly more efficient oxygenation of the liquid in the Air Accordion occurring than in the bubble column. At 1.0 LPM, the Air Accordion's oxygen liquid mass transfer coefficient of 0.00138 s⁻¹ exceeded by 48% that of the bubble column of 0.000931 s⁻¹; and (5) The growth of Scenedesmus obliquus in the Air Accordion significantly exceeded that in the bubble column for both 0.1 LPM and 1.0 LPM. The final algae density of 0.25 g DW/L in the Air Accordion significantly exceeded by 31% that of 0.18 g DW/L in the bubble column at 0.1 LPM. Similarly, the final algae density of 0.37 g DW/L in the Air Accordion significantly exceeded by 19% that of 0.31 g DW/L in the bubble column at 1.0 LPM. Thus, the growth of Scenedesmus obliquus in the Air Accordion photobioreactor -- with significanlty more favorable hydrodynamic characteristics in terms of Residence Time, Vessel Dispersion Number, Mixing Time and oxygen liquid mass transfer coefficient -- significantly exceeded algae growth in the bubble column of the same volume and under the same environmetal conditons.
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Liao, Yang. "Mixotrophic Cultivation Of The Microalga Scenedesmus obliquus With Reused Municipal Wastewater". Thesis, The University of Arizona, 2014. http://hdl.handle.net/10150/332836.
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Scenedesmus obliquus is a freshwater microalga which has high lipid content and biomass productivity. It is regarded as a promising species for production of biodiesel and other valuable organic compounds. Given the high cost of using potable water and commercial fertilizers, the use of municipal wastewater as algal growth medium is attractive in view of its constituent organic carbon and inorganic nutrients, including nitrogen and phosphorus. Investigating the mixotrophic cultivation of S. obliquus in an imitation municipal wastewater, the results of this study showed that: (1) The unmodified imitation wastewater by itself as expected yielded poor S. obliquus growth owing to its pH significantly decreasing to 3.5 as caused by the presence of Ammonium Chloride in the wastewater, inhibiting cell growth; (2) Adding either Acetic Acid or Sodium Acetate to the wastewater medium maintained its pH at 6.5 to 7.0, and its algae biomass on day 6 increased significantly by 212% and 194%, respectively; (3) Adding either Acetic Acid or Sodium Acetate to the wastewater medium maintained its pH at 6.5 to 7.0, and its algae biomass during exponential phase (day 4) significantly exceeded that in the MF control by 220.6% and 165.8%, respectively, while its algae biomass during saturation (day 6) significantly exceeded that in the MF control by 60.8% and 51.5%, respectively; and (4) Addition of NaNO₃ to the wastewater to match the level of N in the MF medium improved the algae biomass by 10%. This study developed ways for how the successful mixotrophic cultivation of S. obliquus in municipal wastewater could be achieved.
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Hung, Isaac, i Isaac Hung. "Ultrafine Bubble-Enhanced Ozonation For Water Treatment". Thesis, The University of Arizona, 2016. http://hdl.handle.net/10150/621853.
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Ultrafine bubbles, often referred to as nanobubbles, have been used in various applications from environmental remediation to medicine. Even though the technology to generate ultrafine bubbles has been around for many years, the full potential of its applications has not been completely studied. This project seeks to study the use of ultrafine bubble technology for water treatment in combination with ozone gas. A factorial design experiment was chosen to test the effects of ultrafine bubbles on the concentration of an indicator organism, E. coli, in water as well as their effects on ozone gas being injected into water. Ozone gas or nitrogen gas was injected into water contaminated with E. coli as either ultrafine bubbles or fine bubbles as treatments for up to 60 minutes. Ultrafine bubbles were found to not have any significant effect on the concentration of E. coli in water. However, ultrafine bubbles did provide benefits when used in conjunction with ozone gas that regular, fine bubbles did not provide. The benefits included allowing the concentration of dissolved ozone in the water to decrease at a slower rate as well as allowing more ozone to dissolve into water at a higher rate than conventional methods of bubbling in ozone. While in this particular set of experiments the concentration of dissolved ozone in water didn't surpass 2 mg/L, which didn't allow for rapid disinfection and treatment of water, it is believed that with a more powerful ozone generator better results can be achieved. This project demonstrates the benefits and potential of injecting ozone gas as ultrafine bubbles into water as a way to effectively and efficiently disinfect and treat water.
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Angus, Scott V. "Development Of Biosensors For Detection Of Pathogens In Complex Sample Matrices". Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/332851.
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Protozoa and bacteria can easily cause disease in humans, specifically E. coli, Plasmodium falciparum, and Cryptosporidium parvum. These three pathogens are associated with large public health concerns that span the globe. The variety of locations in which these can be found is extremely high. Cryptosporidium spp. are extremely resilient when in oocyst form, P. falciparum is in the Anopheles spp. mosquito, while E. coli can be found on anything from food and water, to the skin and gut. The diverse range of locations these can be found in means that a portable sensor for their detection is necessary. In detecting Cryptosporidium, microscopy is the preferred method of identification currently. This requires a trained lab technician as well as calibrated and expensive optical equipment. Technician error can lead to false negative or positive diagnoses as well as sample destruction. A method to remove this technician interaction is thus necessary. This method must allow for objective results that are not open to interpretation. Particle immunoagglutination assays with Mie scatter allow for such an approach using inexpensive components. Particle immunoagglutination relies on the principles of antibody-antigen interaction and antibody conjugated latex particles. Using highly carboxylated latex particles, it is possible to attach IgG antibodies that are specific to a target antigen. Mie scatter is governed by particle size rather than wavelength as other forms of scatter. These two combined allow for an increase in light scatter based on particle size. This is correlated in a linear manner as long as the number of antibody-conjugated particles is higher than the number of antigens. Microfluidics is an ever growing field in the field of lab-on-a-chip that works very well with particle immunoagglutination. In this paper, a method to rapidly identify the presence of Cryptosporidium using microfluidics and particle immunoagglutination is discussed and analyzed. This method allows for a low detection limit of 1-10 oocysts/sample and an assay time of approximately 10 minutes. Results are displayed on a computer screen as the value of light scatter intensity and, when compared to a standard curve, is an objective way to identify the concentration and presence of oocysts in a diverse range of samples. These samples include PBS, pool water, and sump water. This system also works with P. falciparum, which causes malaria in rural and urban poor regions of the world. With the low income and remote nature of these locations, a portable microfluidic device is necessary. Smartphones allow for a portable microfluidic device that can detect P. falciparum antigens in 10% whole blood. This system is capable of detecting as little as 1 pg/mL antigen. The microfluidic chip is inexpensive and disposable, allowing for a portable and inexpensive system. Using a single smartphone, a lab technique requiring a spectrometer, light source, and laptop can be made portable and less expensive, while maintaining sensitivity and specificity. In order to identify biological agents, there are commonly 3 methods for doing so: PCR, culturing, and ELISA. Culturing can take more than 24 hours, but results in a high signal to initial target ratio, while ELISA has poor sensitivity due to a 1:1 signal to target ratio, though is much quicker than culturing at usually 3 hours or less. PCR manages to solve both these problems by exponentially increasing the number of copies of target genetic material in a relatively short time frame of 1-3 hours. PCR relies on 4 basic components: target genetic material, primers to set a start and end location for duplication, polymerase to add base pairs to the strand beginning at the primers, and heat. PCR has worked very well during the past 31 years. It has worked so well that it is often the gold standard. However, there are flaws built into today's systems. These largely come in the form of inefficient heat transfer via conduction and large sample volumes due to unnecessary additions of nuclease free water (NFW). Both of these can be easily overcome by droplet PCR. Droplet PCR relies on small sample volumes of between 8 and 12 μL and convection in oil rather than conduction through plastic. In this study, it was found that droplet PCR could be performed on genomic E. coli DNA in as little as 15 minutes for 30 cycles. Sensitivity was also analyzed and found to be 2.62 pg DNA/μL or about 5 x 10² cfu/sample. PCR has a theoretical lower limit of 1 copy of genetic material and this is only 2 orders of magnitude above that. The system was also tested for portability and resistance to shock and vibration. It was found that the surface heated, thermocouple guided system is more shock and vibration resistant than standard wire guided, hanging droplet PCR systems. It was also found that the use of coconut oil allows for the system to be transported without fear of the contents spilling out and contaminating other samples. This is because of coconut oil's high melting temperature.
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Austin, Ryan Glen. "Detailed Water Quality Modeling of Pressurized Pipe Systems and Its Effect on the Security of Municipal Water Distribution Networks". Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/202714.
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The current study expands on the body of knowledge associated with water distribution system security. The three main chapters focus on 1) the effectiveness of an incomplete mixing model (AZRED-I) with respect to multi-objective sensor placement decisions; 2) risk assessment as a tool for evaluating vulnerability and making sensor placement decisions; and 3) experimental verification of a combined axial-dispersion and incomplete-mixing water quality model (AZRED-II). The study concludes that water quality models do impact sensor placement decisions, especially in highly interconnected networks; that risk assessment is a valuable evaluation tool for providing information concerning a system's vulnerability to contamination and also information that can affect sensor placement decisions; and that AZRED-II is superior to other water quality models at predicting the spatiotemporal pattern of a pulse through a distribution network with cross junctions under laminar flow. The other sections of the study describe the connection that exists between water distribution security and water quality models.
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Story, David Lee Jr. "Autonomous Multi-Sensor and Web-Based Decision Support for Crop Diagnostics in Greenhouse". Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/306925.
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An autonomous machine vision guided plant sensing and monitoring system was designed and constructed to continuously monitor plant related features: color (red-green-blue, hue-saturation-luminance, and color brightness), morphology (top projected canopy area), textural (entropy, energy, contrast, and homogeneity), Normalized Difference Vegetative Index (NDVI) (as well as other similar indices from the color and NIR channels), and thermal (plant and canopy temperature). Several experiments with repeated water stress cycles, using the machine vision system, was conducted to evaluate the machine vision system's performance to determine the timeliness of induced plant water stress detection. The study aimed at identifying significant features separating the control and treatment from an induced water stress experiment and also identifying, amongst the plant canopy, the location of the emerging water stress with the found significant features. Plant cell severity had been ranked based on the cell's accumulated feature count and converted to a color coded graphical canopy image for the remote operator to evaluate. The overall feature analysis showed that the morphological feature, Top Projected Canopy Area, was found to be a good marker for the initial growth period while the vegetation indices (ENDVI, NDVIBlue, and NDVIRed) were more capable at capturing the repeated stress occurrences during the various stages of the lettuce crop. Furthermore, the crop's canopy temperature was shown to be a significant and dominant marker to timely detect the water stress occurrences. The graphical display for the remote user showed the severity of summed features to equal the detection of the human vision. Capabilities and limitations of the developed system and stress detection methodology were documented with recommendations for future improvements for the crop monitoring/production system. An example web based decision support platform was created for data collection, storage, analysis, and display of the data/imagery collected for a remote operator.
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Chen, Lopez Jose Choc. "Characterization, Simulation, Analysis and Management of Hydraulic Properties of Greenhouse Plant Growth Substrates". Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/205211.
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The greenhouse industry is facing significant challenges such as the demand for more efficient use of energy and natural resources and prevention of detrimental environmental impacts. Reducing negative environmental impacts can be achieved by utilizing recycled and environmentally friendly products and by optimizing the use of water and root zone substrates. New and advanced root zone substrates are currently tested as substitute for natural soils in greenhouse agriculture. They can be inert non-organic materials such as rockwool and perlite. These are mined products from the earth, and are difficult to dispose after use. Natural substrates such as peat are being consumed faster than being regenerated. A new potential substrate that consists of recycled foamed glass aggregates is considered an alternative, as it is environmentally friendly, non-toxic and disposable. Experiments with foamed glass aggregates and with foamed glass aggregate/coconut coir mixtures indicated that the yield of greenhouse tomatoes was not statistically significant different (α=0.05) when compared to rockwool. To investigate the potential application of recycled glass as a root zone substrate, physical and hydraulic properties were measured. For comparison, the same measurements were completed for rockwool, coconut coir, perlite, and PET/PE fibers as well as for a mixture of coconut coir and recycled glass. The water characteristics (WC) determined for each substrate exhibited distinct air entry potentials, which provided information for irrigation scheduling, water storage and aeration for optimum plant growth conditions. Coconut coir and rockwool exhibited a unimodal shaped water retention curve, while foamed glass aggregates and perlite exhibited bimodal shaped curves. The obtained substrate properties were used as input paramaters for HYDRUS- 2D/3D model to simulate water mass balance and matric potential distributions within a typical growth container of foamed glass aggregates. The simulated matric potential and water content distributions were compared to tensiometer measurements of matric potential in the foamed glass aggregates. The simulations compared favorably with laboratory experiments measured under controlled environmental conditions.
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Attalah, Said. "Energy evaluation of the High Velocity Algae Raceway Integrated Design (ARID-HV)". Thesis, The University of Arizona, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=1536266.
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The original ARID (Algae Raceway Integrated Design) raceway was an effective method to increase temperature toward the optimal growth range. However, the energy input was high and flow mixing was poor. Thus, the ARID-HV (High Velocity Algae Raceway Integrated Design) raceway was developed to reduce energy input requirements and improve flow mixing. This was accomplished by improving pumping efficiency and using a serpentine flow pattern in which the water flows through channels instead of over barriers. A prototype ARID-HV system was installed in Tucson, Arizona, and the constructability, reliability of components, drainage of channels, and flow and energy requirements of the ARID-HV raceway were evaluated. Each of the electrical energy inputs to the raceway (air sparger, air tube blower, canal lift pump, and channel recirculation pump) was quantified, some by direct measurement and others by simulation. An algae growth model was used to determine the algae production rate vs. flow depth and time of year. Then the electrical energy requirement of the most effective flow depth was calculated. Channel hydraulics was evaluated with Manning's equation and the corner head loss equation. In this way, the maximum length of channels for several raceway slopes and mixing velocities were determined. Algae production in the ARID-HV raceway was simulated with a temperature and light growth model. An energy efficient design for the ARID-HV raceway was developed.
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Terrazas, Onofre Maria Liliana, i Onofre Maria Liliana Terrazas. "Reduction of Bacterial and Viral Indicators in Laundry Graywater by Solar Disinfection". Diss., The University of Arizona, 2016. http://hdl.handle.net/10150/621781.
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Current competitive status among potable and non-potable use makes the water reuse mandatory. Presently, water reuse is common only for reclaimed water coming from municipal or industrial water treatment plants. In those facilities, the treatment includes disinfection. The disinfection methods widely used are chlorination and Ultra Violet (UV) lamps adapted to the conditions of large volume of municipal and industrial systems. This study proposes a disinfection method adequate to the household level to reuse graywater. The method is called solar disinfection (SODIS), which allows the reuse of graywater even though it contains fecal contamination. In this research, natural sun radiation as a free source of heat and UV radiation was utilized. In a first stage, periods of sun exposure, graywater depth, and cell covers as external factors were studied. In later stages, the graywater temperature (GWT) and the UV radiation effects on the reduction of the microbial indicators were observed. Results showed that graywater depth of five cm had a statistical significant reduction rather than ten cm depth (p = 0.0035). Plexiglas and poly-vinyl chloride (PVC), as transparent covers, had a statistical significant reduction (p<0.00001) due to the greenhouse effect increasing the GWT. The black cover had the lowest GWT and reduction of the bacterial and viral indicators. This research found different behavior between bacteria and virus reduction by graywater solar disinfection. In order to reduce the concentration of total coliforms, Escheriquia coli (E. coli) and enterococcus to non-detectable levels (<1.0 most probable number, MPN 100 ml⁻¹), a combination of GWT >45 °C, and UV radiation >24 W m⁻² was required. In contrast, coliphage MS-2, as viral indicator, was resistant to different UV radiation magnitudes (up to 50 W m⁻²), but with a GWT >55 °C non-detectable levels (<1.0 plaques forming units, PFU) were reached.
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Liang, Pei-Shih. "Biosensor Development for Environmental Monitoring, Food Safety, and Secondary Education Applications". Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/311212.
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This dissertation develops biosensors for rapid detection of pathogens for environmental monitoring and food safety applications and utilizes the multidisciplinary and multi-application characteristics of biosensors to develop a lesson plan that can be implemented in secondary education classrooms. The detection methods evolve from particle immunoagglutination assay, PDMS optofluidic lab-on-a-chip, and spectrum analysis to smartphone and image analysis without any reagent; the potential application in secondary education also underlines the extended value of biosensors. In the first paper presented here, an optofluidic lab-on-a-chip system and subsequent sampling procedure were developed for detecting bacteria from soil samples utilizing Mie scattering detection of particle immunoagglutination assay. This system and protocol detected the presence of Escherichia coli K12 from soil particles in near real-time (10 min) with a detection limit down to 1 CFU mL⁻¹ and has the potential to be implemented in the field. We also compared the interaction between E. coli and soil particles to the two-step protein-surface interaction. In the second paper, a smartphone-utilized biosensor consisting of a near-infrared (NIR) LED (wavelength of 880 nm) and a digital camera of a smartphone was developed for detecting microbial spoilage on ground beef, without using any reagents. The method was further improved by programming a smartphone application that allows the user to position the smartphone at an optimum distance and a range of angles utilizing its internal gyro sensor to measure a series of scatter intensities against the detection angle. This handheld device can be used as a preliminary screening tool to monitor microbial contamination on meat products. In the third paper, we designed a lesson plan for secondary education classrooms using biosensors as a core and branching out to different applications and fields of study with the goal of heightening students' interest and motivation toward attaining degrees and careers in STEM fields. Results revealed that the lesson was more effective in affecting younger students than older students, and more effective in teaching about the applications of biosensors than about the techniques of biosensor development.
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Rojas, Ortúzar Ilse. "Bioconversion Of Lignocellulosic Components Of Sweet Sorghum Bagasse Into Fermentable Sugars". Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/555836.
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The utilization of lignocellulosic residues to produce renewable energy is an interesting alternative to meet the increasing demand of fuels while at the same time reducing greenhouse gas emissions and climate change. Sweet sorghum bagasse is a lignocellulosic residue composed mainly of cellulose, hemicellulose, and lignin; and it is a promising substrate for ethanol production because its complex carbohydrates may be hydrolyzed and converted into simple sugars, and then fermented into ethanol. However, the utilization of lignocellulosic residues is difficult and inefficient. Lignocellulose is a very stable and compact complex structure, which is linked by β-1,4 and β-1,3 glycosidic bonds. Furthermore, the crystalline and amorphous features of cellulose fibers and the presence of hemicellulose and lignin make the conversion of lignocellulose into fermentable sugars currently impractical at commercial scale. The bioconversion of lignocellulose in nature is performed by microorganisms such as fungi and bacteria, which produce enzymes that are able to degrade lignocellulose. The present study evaluated the bioconversion of lignocellulosic residues of sweet sorghum into simple sugars using filamentous fungi directly in the hydrolysis of the substrate, without prior isolation of the enzymes. The fungus Neurospora crassa and some wild fungi (that grew naturally on sweet sorghum bagasse) were used in this investigation. The effect of the fungi on substrate degradation and the sugars released after hydrolysis were evaluated, and then compared with standard hydrolysis performed by commercial enzymes (isolated cellulases). In addition, different combinations of fungi and enzymes were used to determine the best approach. The main goal was to verify if the fungi were able to attack and break down the lignocellulose structure directly and at a reasonable rate, rather than by the current method utilizing isolated enzymes. The main finding of this study was that the fungi (N. crassa and wild fungi) were able to degrade sweet sorghum bagasse directly; however, in all of the cases, the hydrolysis process was not efficient because the hydrolysis rate was much lower than the enzymatic hydrolysis rate. Hydrolysis using a combination of fungus and commercial enzymes was a good approach, but still not efficient enough for practical use. The best results of combined hydrolysis were obtained when the substrate was under the fungus attack for three days and then, commercial enzymes with low enzymatic activity (7 FPU/g and 25 CBU/g) were added to the solution. These enzymes represent 10% of the current enzymatic activity recommended per gram of substrate. This process reached reasonable levels of sugars (close to 85% of sugars yield obtained by enzymatic hydrolysis); however, the conversion rate was still slower, making the process impractical and more expensive since it took twice the amount of time as commercial enzymes. Furthermore, the wild fungi able to degrade cellulose were isolated, screened, and identified. Two of them belong to the genus Aspergillus, one to the genus Acremonium, and one to the genus Rhizopus. Small concentration of spores-0.5mL- (see Table 4, CHAPTER III- for specific number of spores per mL) did not show any sugar released during hydrolysis of sweet sorghum bagasse. However, when the concentration of spores was increased (to 5mL and 10mL of solution), citric acid production was detected. This finding indicates that those wild fungi were able to degrade lignocellulose, even though no simple sugars were measured, citric acid production is an indicator of fungi growing and utilization of lignocellulose as nutrient. It is assumed that the fungi consume the sugars at the same time they are released, thus they are not detected. The maximum concentration of citric acid (~14.50 mg/mL) was achieved between days 8-11 of hydrolysis. On the other hand, before using lignocellulose, the substrate needed to be pretreated in order to facilitate its decomposition and subsequent hydrolysis. Sweet sorghum bagasse was washed three times to remove any soluble sugars remaining after the juice was extracted from the stalks. Then, another finding of this study was that the first wash solution could be used for ethanol production since the amount of sugars present in it was close to 13°Brix. The ethanol yield after 48 hours of fermentation was in average 6.82mg/mL, which is close to the theoretical ethanol yield. The other two washes were too dilute for commercial ethanol production. In terms of pretreatments, the best one to break down sweet sorghum bagasse was 2% (w/v) NaOH. This pretreatment shows the highest amounts of glucose and xylose released after hydrolysis. Unwashed and untreated bagasse (raw bagasse) did not show any sugar released. In terms of ethanol, 74.50% of the theoretical yield was reached by enzymatic hydrolysis, while 1.10% was reached by hydrolysis using the fungus N. crassa. Finally, it is important to remark that further investigation is needed to improve the direct conversion of lignocellulose into fermentable sugars by fungal enzymes. This approach is a promising technology that needs to be developed and improved to make it efficient and feasible at commercial scale.
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Lee, Montiel Felipe Tadeo. "A Biosensor Approach for the Detection of Active Virus Using FTIR Spectroscopy and Cell Culture". Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/204913.
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Worldwide, 3.575 million people die each year from water-related diseases. The water and sanitation crisis claims more lives than any warfare and is predicted to be one of the biggest global challenges of this century. The rapid, accurate detection of viral pathogens from environmental samples is an ongoing and pertinent challenge in biological engineering. Currently employed methods are lacking in either efficiency or specificity. Here we explore a novel method for virus detection and concurrently use this method to learn more about the very early stages of the virus infection process. The method combines Fourier transform infrared (FTIR) spectroscopy, a method of visualizing molecules based on changes in vibration of particles, and mammalian cells as the biosensor. This method is used to detect and investigate viruses from the family picornaviridae, chosen due to their public health burden and their widespread presence in environmental samples, especially water sources. This family includes the Polioviruses, echoviruses and Coxsackieviruses, among others, many of which are human pathogens.The research outlined in this dissertation is aimed at developing and implementing a new cell-based biosensor that combines the advantages of FTIR spectroscopy with the ability of buffalo green monkey kidney (BGMK) cells to sense diverse stimuli, including infective enteroviruses. The goal of developing this biosensor is outlined in the first paper. The second paper focuses on the application of advanced statistical methods to analyze the spectra to discriminate different viral infections in BGMK cells. Finally, we designed a non-reactive metal biochamber to use with attenuated total reflectance-FTIR. This allowed near-continuous acquisition of real-time spectral data for the study of biochemical changes in mammalian cells caused by poliovirus (PV1) infection. This system is capable of tracking changes in cell biochemistry in minute intervals for many hours at a time.This work demonstrates the feasibility of FTIR spectroscopy in combination with the broad sensitivity of mammalian cells for potential use in the detection of infective viruses from environmental samples. We envision this method being extended to high throughput, automated systems to screen for viruses or other toxins in drinking water systems and medical applications.
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Rojano, Aguilar Fernando. "Computational Modeling to Reduce Impact of Heat Stress in Lactating Cows". Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/272838.
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Climatic conditions inside the dairy barn do not concern dairy farmers until those conditions begin to affect productivity and, consequently, profits. As heat and humidity increase beyond the cow's comfort levels, milk production declines, as does fertility and the welfare of the cow in general. To reinforce the cooling mechanisms currently used, this work proposes an alternative system for reducing the risk of heat stress. This innovative conductive cooling system does not depend on current weather conditions, and it does not require significant modifications when it is installed or during its operation. Also, the system circulates water that can be reused. Given that a review of the literature found very few related studies, it is suggested that each freestall be equipped with a viable prototype in the form of a waterbed able to exchange heat. Such a prototype has been simulated using Computational Fluid Dynamics (CFD) and later verified by a set of experiments designed to confirm its cooling capacity. Furthermore, this investigation sets the foundation for modeling temperature in a water supply system linked to the waterbeds. EPANET, a software program developed by the Environmental Protection Agency, simulates the hydraulic model. Its Water Quality Solver has been modified according to an analogy in the governing equation that compares mass to heat transfer and serves to simulate water temperature as the water is transported from its source to the point of delivery and then as it returns to the same source.
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Laugksch, Diane. "Studying science and engineering at UCT : students' background, experience of science an reasons for studying science or engineering". Thesis, Stellenbosch : Stellenbosch University, 2007. http://hdl.handle.net/10019.1/19637.
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Thesis (MPhil)--University of Stellenbosch, 2007.ENGLISH ABSTRACT: It is the contention of this study that competence in science and mathematics is a necessary condition for access to higher education, but that it is a general interest in science that will inspire learners to pursue careers in science and technology. The objective of this study was to develop a profile of the individual who chooses to study science and engineering. The three research questions were, firstly, what is the background profile of a group of learners who have decided to study science and engineering? Secondly, what are the characteristic features of the school-science experience of these learners? Lastly, what are the factors that learners think most influenced their decision to study science and engineering? This study was formulated as having a descriptive purpose and hence a survey research design was used. Self-reported retrospective data were collected using a questionnaire which was designed with reference to a number of sources (e.g., Woolnough, 1994). After piloting the questionnaire, it was administered to all firstyear students registered in the faculties of Science and Engineering at the University of Cape Town. A total of 204 first-year science and 247 first-year engineering students formed the final sample of this study. Quantitative analysis of the students’ responses showed that 66% of respondents were male. The majority of female students were registered in the science faculty. English was the home language of 55% of the sample, with 32% of students reported speaking one of the other nine official languages at home. Parents, career counselors and teachers most influenced students’ decision to study science or engineering. The vast majority of respondents took Physical Science at school. Students’ experiences of school science were diverse. Students’ responses generally reflected a poor commitment on the part of schools to expose students to noncurriculum activities generally thought to promote an interest in science. Overall, the majority of students reflected an enthusiasm for learning to do science through scientific experiments, albeit with preference for a teacher-driven approach to classroom activities. Personal motivation, receiving a bursary, and access to information were the main factors that students said influenced their decision to study science and engineering. While information received at a careers open day and participating in a school science competition was crucial for science students, engineering students showed a general curiosity for science, for knowing how things work, and for creating and designing things. For most African students information received at a careers open day was important, while a curiosity for science and receiving a bursary were equally important in influencing non-African students to pursue further study in science or engineering. The results of this study suggest that what parents say, and the information that learners have access to, is important to the decisions that learners make in regard to future careers in science and engineering. It is suggested that future strategies for promoting science in general must include parents, teachers and senior learners in the dissemination of general information about science, about people in science, about using science in everyday life, and about the possibilities for further study in science and engineering.
AFRIKAANSE OPSOMMING: Dit is die uitgangspunt van hierdie ondersoek dat vaardigheid in die wetenskap en wiskunde ‘n noodsaaklike voorwaarde is vir toegang to tersiêre onderwys, maar dat ‘n algemene belangstelling in die wetenskap leerders sal inspireer om loopbane in die natuurwetenskappe en tegnologie te volg. Die doel van hierdie ondersoek was om ‘n profiel te ontwikkel van die individu wat die natuurwetenskappe en ingenieurswese kies as studierigting. Die drie navorsingsvrae was, eerstens, wat is die agtergrondsprofiel van leerders wat besluit om in die natuurwetenskappe en ingenieurswese te studeer? Tweedens, wat is die kenmerkende eienskappe van hierdie leerders se skoolervaring? Laastens, watter faktore dink hierdie leerders het hulle besluit om in die natuurwetenskappe en ingenieurswese te studeer, die meeste beïnvloed? Hierdie ondersoek is beskrywend van aard en dus is ‘n steekproef as navorsingsontwerp gebruik. Selfgerapporteerde retrospektiewe data is ingesamel deur middel van ‘n vraelys wat ontwerp is met verwysings na ‘n verskeidenheid bronne (bv., Woolnough, 1994). Die vraelys is versprei aan alle eerste-jaar geregistreerde studente in die Natuurwetenskappe en Ingenieurswese Fakulteite by die Universiteit van Kaapstad, nadat ‘n voortoetsing van die vraelys uitgevoer is. ‘n Totaal van 204 eerste-jaar natuurwetensakppe en 247 eerste-jaar ingenieurswese studente was deel van die finale steekproef van hierdie ondersoek. Die kwantitatiewe ontleding van die studenteterugvoer toon dat 66% van die respondente manlik is. Die meerderheid vroulike studente was geregistreer in die natuurwetenskappe fakulteit. Engels was die huistaal van 55% van die steekproef, en 32% van die studente het aangedui dat hulle een of meer van die ander nege amptelike landstale praat. Ouers, beroepsvoorligters en onderwysers het die meeste invloed gehad op die studente se besluit om in die natuurwetenskappe of ingenieurswese te studeer. Die oorgrote meerderheid respondente het Natuur- en Skeikunde op skool geneem. Studente se skoolervarings en ervaring van die wetenskap op skool was uiteenlopend. Studente se terugvoer het in die algemeen gedui op ‘n swak verbintenis van skole tot die blootstelling van studente aan niekurrikulêre aktiwiteite wat oor die algemeen belangstelling in die wetenskap kweek. Die meerderheid studente het in die geheel ‘n entoesiasme getoon om meer te leer van die wetenskap deur die uitvoer van wetenskaplike eksperimente, hoewel met ‘n voorkeur vir ‘n onderwyser-gedrewe benadering tot klaskamer aktiwiteite. Persoonlike motivering, om ‘n beurs te ontvang, en toegang tot inligting is deur studente aangedui as van die vernaamste faktore wat ‘n invloed op hulle keuse van die natuurwetenskappe en ingenieurswese as studierigting gehad het. Die inligting wat die natuurwetenskappe studente ontvang het by beroepsgeoriënteerde opedae en deelname in ‘n skool wetenskapskompetisie was beslissend in hulle besluit. Die ingenieurswese studente daarteenoor het ‘n algemene nuurskierigheid vir die wetenskap en hoe dinge werk, hoe om dinge te skep en te ontwerp, getoon. Die inligting wat swart studente by beroepsgeoriënteerde opedae ontvang het, was belangrik, terwyl ‘n wetenskaplike nuuskierigheid en die toekenning van ‘n beurs ‘n ewe belangrike invloed gehad het op ander studente se keuse om verdere studie in die natuurwetenskappe of ingenieurswese voort te sit. Die resultate van hierdie ondersoek dui daarop dat wat ouers sê, en die inligting waartoe leerders toegang het, belangrik is vir die besluite wat leerders neem met betrekking tot toekomstige loopbane in die natuurwetenskappe en ingenieurswese. Daar word voorgestel dat toekomstige strategieë vir die bevordering van die wetenskap in die algemeen ouers, onderwysers en senior leerders moet insluit in die verspreiding van algemene inligting oor die wetenskap, oor mense in die wetenskap, oor die gebruik van die wetenskap in die alledaagse lewe, en die moontlikhede van verdere studies in die natuurwetenskappe en ingenieurswese.
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Tulchak, L. V., A. S. Alieksieienko, Л. В. Тульчак i А. С. Алєксєєнко. "Oscilloscope in science and engineering". Thesis, Вінницький національний аграрний університет, 2015. http://ir.lib.vntu.edu.ua/handle/123456789/7680.
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An oscilloscope, previously called an oscillograph, and informally known as a scope, CRO (for cathode-ray oscilloscope), or DSO (for the more modern digital storage oscilloscope), is a type of electronic test instrument that allows observation of constantly varying signal voltages, usually as a two-dimensional plot of one or more signals as a function of time. Non-electrical signals (such as sound or vibration) can be converted to voltages and displayed
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White, Craig (Craig E. ). 1971. "Science fiction to science fact : the link between early science fiction and the space programs". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/9572.
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Pookhao, Naruekamol. "Statistical Methods for Functional Metagenomic Analysis Based on Next-Generation Sequencing Data". Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/320986.
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Metagenomics is the study of a collective microbial genetic content recovered directly from natural (e.g., soil, ocean, and freshwater) or host-associated (e.g., human gut, skin, and oral) environmental communities that contain microorganisms, i.e., microbiomes. The rapid technological developments in next generation sequencing (NGS) technologies, enabling to sequence tens or hundreds of millions of short DNA fragments (or reads) in a single run, facilitates the studies of multiple microorganisms lived in environmental communities. Metagenomics, a relatively new but fast growing field, allows us to understand the diversity of microbes, their functions, cooperation, and evolution in a particular ecosystem. Also, it assists us to identify significantly different metabolic potentials in different environments. Particularly, metagenomic analysis on the basis of functional features (e.g., pathways, subsystems, functional roles) enables to contribute the genomic contents of microbes to human health and leads us to understand how the microbes affect human health by analyzing a metagenomic data corresponding to two or multiple populations with different clinical phenotypes (e.g., diseased and healthy, or different treatments). Currently, metagenomic analysis has substantial impact not only on genetic and environmental areas, but also on clinical applications. In our study, we focus on the development of computational and statistical methods for functional metagnomic analysis of sequencing data that is obtained from various environmental microbial samples/communities.
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KWON, HYUCK JIN. "Detection and Monitoring of Pathogens in Animal and Human Environment by a Handheld Immunosensor and CFD Simulation". Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/203493.
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This research demonstrates technology for detection of pathogens and environmental monitoring using a handheld optofluidic immunosensor and CFD simulation. The current methods such as ELISA and PCR require few hours for identification which means it is unavailable for early-monitoring. The use of a near-real-time, handheld biosensor device in a real animal/human environment is the key to monitoring the spread of dangerous pathogens. A 3-D computational fluid dynamics (CFD) simulation is needed to track the pathogens within an environment.This dissertation has four papers that demonstrate technologies for the detection and monitoring of pathogens and the miniaturization of these detection systems for in field applications with a handheld immunosensor and CFD simulation.In the first paper, an environmental prediction model was developed for optimal ventilation in a mushroom house by using sensible heat balance and 3-D CFD method. It is shown that the models can be used for farmers to predict the environmental conditions over different locations in a mushroom house.In the second paper, a field lab-on-a-chip system was constructed to detect mouse immunoglobulin G and Escherichia coli by using light scattering detection of particle immunoagglutination. Antibody-conjugated particles were able to be stored in a 4°C refrigerator for at least 4 weeks and to be lyophilized as a powder form for the storage in room temperature.In the third paper, rapid monitoring of the spreads of porcine reproductive and respiratory syndrome virus (PRRSV) was attempted using samples collected from nasal swabs of pigs and air samplers within an experimental swine building. An optofluidic device containing liquid-core waveguides was used to detect. It is shown that the developed optofluidic device and 3-D CFD model can serve as a good model for monitoring the spread of airborne viruses within animal and human environments.In the fourth paper, a handheld optofluidic immunosensor was developed for rapid detection of H1N1/2009 virus inside a 1:10 scale mock classroom. Both miniature spectrometer and cell phone camera were used as detector. A 3-D computational fluid dynamics (CFD) model was developed to track the transport/distribution of H1N1/2009 viruses, and corresponded very well with immunosensor readings.
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Maguire, John F. "Contributions to materials science and engineering". Thesis, Ulster University, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.515891.
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Andrade-Rodriguez, Manuel Alejandro. "Computationally Intensive Design of Water Distribution Systems". Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/301704.
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The burdensome capital cost of urban water distribution systems demands the use of efficient optimization methods capable of finding a relatively inexpensive design that guarantees a minimum functionality under all conditions of operation. The combinatorial and nonlinear nature of the optimization problem involved accepts no definitive method of solution. Adaptive search methods are well fitted for this type of problem (to which more formal methods cannot be applied), but their computational requirements demand the development and implementation of additional heuristics to find a satisfactory solution. This work seeks to employ adaptive search methods to enhance the search process used to find the optimal design of any water distribution system. A first study presented here introduces post-optimization heuristics that analyze the best design obtained by a genetic algorithm--arguably the most popular adaptive search method--and perform an ordered local search to maximize further cost savings. When used to analyze the best design found by a genetic algorithm, the proposed post-optimization heuristics method successfully achieved additional cost savings that the genetic algorithm failed to detect after an exhaustive search. The second study herein explores various ways to improve artificial neural networks employed as fast estimators of computationally intensive constraints. The study presents a new methodology for generating any large set of water supply networks to be used for the training of artificial neural networks. This dataset incorporates several distribution networks in the vicinity of the search space in which the genetic algorithm is expected to focus its search. The incorporation of these networks improved the accuracy of artificial neural networks trained with such a dataset. These neural networks consistently showed a lower margin of error than their counterparts trained with conventional training datasets populated by randomly generated distribution networks.
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Tollefson, Stacy Joy. "Compost Water Extracts And Suppression Of Root Rot (F. Solani F. Sp. Pisi) In Pea: Factors Of Suppression And A Potential New Mechanism". Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/338972.
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One of the motivating reasons for the development of hydroponics was avoidance of root pathogens. Hydroponics involves growing crops in relatively sterile media, isolated from the underlying soil which may have disease pressure. However, even when hydroponics is coupled with controlled environments such as high tunnels and climate-controlled greenhouses, soil-borne pathogens can enter the growing area and proliferate due to optimal environmental conditions for pathogen growth. Control of root pathogens is difficult and usually achieved through synthetic fungicides since few biocontrol options are available. Compost water extracts (CWE) have recently been gaining the attention of greenhouse growers because they may be a low-cost, environmentally friendly approach to control root disease. CWE are mixtures of compost and water incubated for a defined period of time, either with or without aeration, and with or without additives intended to increase microbial populations, which in turn suppress disease. Much anecdotal, but very little scientific, evidence exists describing CWE effect on suppressing soil-borne pathogens. The present study 1) examined the effect of an aerated CWE on disease suppression at the laboratory scale and in container studies using different soilless substrates, 2) investigated a phenotypic change at the root level caused by CWE that may be associated with disease suppression, and 3) isolated some factors in the production of CWE that affect the ability of a CWE to suppress disease. The common model pathogen-host system of Fusarium solani f.sp. pisi and pea was used to examine CWE-induced disease suppression, with information then being translatable to similar patho-systems involved in greenhouse crop production. In the first study, laboratory-based root growth and infection assays resulted in 100% suppression of F. solani when roots were drenched in CWE. These protected seedlings were then taken to a greenhouse and transplanted into fine coconut coir, watered with hydroponic nutrient solution, and grown for five weeks. At the end of the experiment, 23% of the shoots of the pathogen-inoculated, CWE-drenched seedlings remained healthy while only 2% of the inoculated seedlings without CWE drench remained healthy. All of the roots of the inoculated seedlings developed lesions, even those drenched in CWE. However, 29% of the CWE drenched roots were able to recover from disease, growing white healthy roots past the lesion, while only 2% recovered naturally. A shorter-term container study was conducted in the laboratory to determine the effects of CWE-induced suppression when peas were grown in different substrates and to determine if the hydroponic nutrient solution had an effect on the suppression. Peas were grown in sterilized fine and coarse coconut coir fiber and sand irrigated with water, with a second set of fine coir irrigated with hydroponic nutrient solution. Pea seeds with 20-25mm radicles were inoculated with pathogen and sown directly into CWE-drenched substrate and grown for three weeks. At the end of the experiment, 80%, 60%, 90%, and 50% of the shoots of the inoculated, CWE-drenched seedlings remained healthy when grown in fine coir, coarse coir, sand, and fine coir irrigated with hydroponic nutrient solution, respectively. Nearly 100% of the roots grown in coconut coir substrates again developed necrotic lesions but 83%, 87%, 100%, and 87% grew healthy roots beyond the disease region. The hydroponic nutrient solution had a negative effect on suppression, with a reduction of at least 30 percentage points. Sand demonstrated a natural ability to suppress F. solani. Only 23% of inoculated seedlings had dead or dying shoots by the end of the experiment (compared to 77-80% in coir substrates) and although all but one of the roots developed lesions, all were able to recover on their own with CWE. CWE further increased shoot health and also prevented 57% of the roots from developing lesions. In a second study, two different CWE were used to examine the effect on root border cell dispersion and dynamics in pea, maize, cotton, and cucumber and its relation to disease suppression. Dispersal of border cells after immersion of roots into water or CWE was measured by direct observation over time using a compound microscope and stereoscope. Pictures were taken and the number of border cells released into suspension were enumerated by counting the total number of cells in aliquots taken from the suspension. Border cells formed a mass surrounding root tips within seconds after exposure to water, and most cells dispersed into suspension spontaneously. In CWE, >90% of the border cell population instead remained appressed to the root surface, even after vigorous agitation. This altered border cell phenomena was consistent for pea, maize, and cotton and for both CWE tested. For most cucumber roots (n=86/95), inhibition of border cell dispersal in both CWE was similar to that observed in pea, maize, and cotton. However, some individual cucumber roots (8±5%) exhibited a distinct phenotype. For example, border cells of one root immersed into CWE remained tightly adhered to the root tip even after 30 minutes while border cells of another root immersed at the same time in the same sample of CWE expanded significantly within 5 minutes and continued to expand over time. In a previous study, sheath development over time in growth pouches also was distinct in cucumber compared with pea, with detachment of the sheaths over time, and root infection was reduced by only 38% in cucumber compared with 100% protection in pea (Curlango-Rivera et al. 2013). Further research is needed to evaluate whether this difference in retention of border cell sheaths plays a role in the observed difference in inhibition of root infection. In the third study, a series of investigations were conducted to isolate different factors that contribute to the suppression ability of a CWE by changing incrementally changing some aspect of the CWE production process. The basic aerated CWE recipe (with molasses, kelp, humic acid, rock phosphate, and silica) provided 100% protection of pea from root disease while the non-aerated basic recipe CWE provided 72% protection. Aerated CWE made of only compost and water resulted in 58% protection. It was found that molasses did not contribute to the suppression ability of the ACWE, while kelp contributed strongly. When soluble kelp was added by itself to the compost and water, the CWE provided 80% suppression. However, when all additives were included except molasses and kelp, suppression remained high (93%) indicating that humic acids, rock phosphate, and/or silica were also major contributors toward the suppression effect. Optimal fermentation time for ACWE was 24 hr to achieve 100% suppression, with increased time resulting in inconsistent suppression results. Optimal fermentation time for NCWE was 3 days or 8 days. These studies are important contributions to understanding the differences that might be expected in CWE suppression when growing in different substrates, some of the factors in the production of CWE that affects the ability of a CWE to suppress disease, and the phenotypic effect CWE has on the root zone of plants and the possible relationship between that effect and disease suppression.
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Savage, Guy. "Holacratic Engineering Management| A Lean Enterprise System Engineering Innovation". Thesis, The George Washington University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10785338.
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Based on a belief that innovation is increased by Holacratic Engineering Management practices distributing authority to engaged, autonomous, decision makers versus traditional corporate, hierarchical, and delegated decision making, this research examines the relationship between holacratic engineering management and company innovative performance. This proposed new, chaordic, systems engineering and engineering management process, inherently disruptive and arising out of the agile software and lean systems engineering disciplines, is explored using systems thinking and model-based systems engineering principles. This research effort examining Holacratic Engineering Management, an adoptive innovation of lean and agile engineering concepts as a convergence of Holacracy and Lean Enterprise System Engineering includes case studies measuring the effects of Holacratic Engineering Management and Lean Enterprise Systems Engineering on performance. Using soft systems methodology, multiple linear regression is performed on 18 companies that design, develop, and deliver prepackaged software. The theoretical model consists of five component values comprising the holacracy measurements. Companies embracing Holacratic Engineering Management have significantly improved innovation performance.
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Alrabghi, Leenah O. "QFD IN SOFTWARE ENGINEERING". Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1385046526.
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Wason, Jasmin Lesley. "Automating data management in science and engineering". Thesis, University of Southampton, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.396143.
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Blackie, Margaret, Roux Kate Le i Sioux McKenna. "Possible futures for science and engineering education". Springer Netherlands, 2016. http://hdl.handle.net/10962/66796.
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Publisher versionFrom Introduction: The understanding that the science, engineering, technology and mathematics disciplines (STEM) have a significant and directly causal role to play in economic productivity and innovation has driven an increased focus on these fields in higher education. Innovation in this context is a shorthand for the harnessing of the knowledge economy and the provision of products with novel significant ‘added value’. The assumption in both developed and developing economies alike is that STEM will drive national growth (World Bank 2002; UNESCO 2009), and this impacts on demands that universities provide competent graduates in sufficient numbers. However, exactly what ‘competency’ might mean in this context is open to debate.
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Jia, Fei. "Multivariable And Sensor Feedback Based Real-Time Monitoring And Control Of Microalgae Production System". Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/579045.
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A multi-wavelength laser diode based optical sensor was designed, developed and evaluated for monitoring and control microalgae growth in real-time. The sensor measures optical density of microalgae suspension at three wavelengths: 650 nm, 685 nm and 780 nm, which are commonly used for estimating microalgae biomass concentration and chlorophyll content. The sensor showed capability of measuring cell concentration up to 1.05 g L⁻¹ without sample dilution or preparation. The performance of the sensor was evaluated using both indoor photobioreactors and outdoor paddle wheel reactors. It was shown that the sensor was capable of monitoring the dynamics of the microalgae culture in real-time with high accuracy and durability. Specific growth rate (μ) and ratios of optical densities (OD ratios) at different wavelengths were calculated and were used as good indicators of the health of microalgae culture. A series of experiments was conducted to evaluate the sensor's capability of detecting environmental disturbances in microalgae systems, for instance, induced by dust or Vampirovibrio chlorellavorus, a bacteria found to cause crash of microalgae culture. Optical densities measured from the sensor were insensitive to the amount of dust that consisted of 59.7% of dry weight of microalgae in the system. However, the sensor was able to detect multiple events of introduction of dust timely by μ and OD ratios. The sensor was also capable of detecting subtle changes of culture in color that leads to a total crash of the culture before it can be differentiated by naked eye. The sensor was further integrated into an existing outdoor raceway to demonstrate the sensor's potential of being a core component to control microalgae production system. A real-time monitoring and control program along with a graphical user interface (GUI) was developed for a central control station aiming at improving resource use efficiency for biomass production.
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Villarreal, Guerrero Federico. "Enhanced Greenhouse Cooling Strategy with Natural Ventilation and Variable Fogging Rates". Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/202717.
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High-pressure fog (HPF) systems have advantages for greenhouse cooling compared to traditional systems, such as pad and fan. Such advantages include the potential of improving climate uniformity. Water is distributed throughout the greenhouse space thus reducing water use and energy operation costs, especially if used within naturally ventilated greenhouses. Fog cooling in combination with natural ventilation is difficult to manage, primarily because accurate estimation of air exchange rates is required to determine the precise amount of fog required. This limitation on automated control has been the main reason restricting the widespread commercial use of HPF systems. The goal of this research was to develop and implement a control strategy for a naturally ventilated greenhouse with a variable HPF system. The strategy that was developed included variable rate of fog introduced into the greenhouse, a dynamic control of the air ventilation openings, and it considered the contribution of cooling and humidification from the crop by evapotranspiration. Three evapotranspiration models, including Penman-Monteith, Stanghellini and Takakura, were calibrated and evaluated in terms of prediction accuracy. The Stanghellini model provided the best overall performance for several growing seasons and under two different evaporative cooling systems (i.e. pad and fan and natural ventilation with HPF), and was selected and implemented in the cooling control strategy. The strategy utilized enthalpy and vapor pressure deficit (VPD) of the greenhouse atmosphere for the control parameters. Using a calibrated greenhouse mechanistic climate model, a computer algorithm was created to simulate the capabilities of the proposed. The control strategy that was developed was able to maintain the greenhouse climate closer to the pre-established set points while consuming less water and energy, compared to a constant HPF system based on VPD control. Finally, the strategy was implemented in a single span research greenhouse. A four-day validation study provided good agreement for measured and simulated greenhouse climate values, as well as for water and energy use. Moreover, the strategy was able to maintain VPD around its set point for all the experiments and temperature remained around its set point when outside enthalpy was lower than the enthalpy set point.
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Pupim, Eliana Kátia [UNESP]. "Análise cientométrica comparativa entre dois campos científicos: engenharia agrícola e engenharia de biossistemas". Universidade Estadual Paulista (UNESP), 2018. http://hdl.handle.net/11449/154407.
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A profissão do Engenheiro de Biossistemas ainda é recente no Brasil, sendo que a implantação do primeiro curso superior ocorreu em 2009. Em função da sua afinidade com a Engenharia Agrícola, os órgãos reguladores da profissão de Engenharia ainda não reconhecem seus egressos como Engenheiros de Biossistemas, mas sim os intitulam de Engenheiros Agrícolas com especificidade em Biossistemas. Diante desta problemática, o objetivo desta pesquisa foi traçar paralelos entre os campos científicos das Engenharia Agrícola e Engenharia de Biossistemas, de forma a permitir a elaboração de subsídios que levem à compreensão dos pontos de proximidade e de distanciamento dos domínios estudados. O método utilizado para alcançar o objetivo proposto foi a Análise de Domínio, optando pelas abordagens com Estudos Históricos e Estudos Bibliométricos, com a adoção da análise de conteúdo de Bardin e a elaboração de nuvens de palavras para as analogias. Os resultados permitiram compreender que sim, há vários momentos em que a Engenharia de Biossistemas e a Engenharia Agrícola são análogas, como na organização e na duração e integralização dos cursos, porém quanto aos conteúdos disseminados oferecem uma variação quanto aos temas relacionados à Zootecnia e Ciências Biológicas, sendo que enquanto a Engenharia de Biossistemas os trata como temas centrais, a Engenharia Agrícola os tem como temáticas periféricas. A produção científica também tem suas características peculiares, havendo periódicos que publicam apenas o conteúdo de uma ou de outra Engenharia, contudo há em número maior os periódicos que publicam as duas Engenharias concomitantemente, demonstrando que apesar de suas especificidades, há muito em comum na Engenharia de Biossistemas e na Engenharia Agrícola.
The profession of the Biosystems Engineer is very recent in Brazil. The first undergraduate major was implemented in 2009. Due to its affinity with Agricultural Engineering, the regulatory entities of the Engineering majors in Brazil do not recognize its graduates as Biosystems Engineers, but rather call them Agricultural Engineers with specificity in Biosystems. In view of this problem, the objective of this research was to draw parallels between the scientific fields of Agricultural Engineering and Biosystems Engineering, in order to find information that lead to understanding the points of proximity and distancing of the studied domains. The method used to reach the proposed goal was Domain Analysis, opting for approaches with Historical Studies and Bibliometric Studies, with the adoption of the Bardin content analysis and the elaboration of word clouds to allow for comparisons. The results allowed us to understand that there are several moments in which Biosystems Engineering and Agricultural Engineering are similar, as in the organization and duration and completion of the majors. However, the disseminated contents offer a variation regarding the subjects related to Zootechnics and Sciences Biological Sciences. While Engineering of Biosystems treats them as central themes, Agricultural Engineering has them as peripheral themes. Scientific production also has its peculiar characteristics, and there are periodicals that publish only the content of one or the other Engineering, however there are in greater number periodicals that publish the two Engineering concomitantly, demonstrating that despite their specificities, there is much in common in Engineering Biosystems and Agricultural Engineering.
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Handa, Sunny. "Reverse engineering computer programs under Canadian copyright law". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=22693.
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The field of copyright law has been especially active in recent times as a result of its application to computer programs. Copyright law, not originally designed to protect such works, has had to adapt to suit the special nature of computer programs. This paper addresses the applicability of copyright law to the reverse engineering of computer programs. Reverse engineering is a method by which programmers may uncover the ideas and processes used within an existing computer program, thereby allowing the construction of compatible computer programs. Reverse engineering may also be used to create works which are directly competitive with the original program, and may also be used to assist in the piracy of computer programs. The mere act of reverse engineering computer programs, regardless of its purpose, potentially infringes the copyright of the computer program in question, notwithstanding whether the results of the process are used in an infringing manner.Recently both the European Union countries and the United States have accepted reverse engineering as an exception to copyright infringement. The European Union has opted for a legislative solution, whereas in the United States several courts have construed the fair use exception contained in that country's Copyright Act as allowing reverse engineering.
In this paper, it is argued that Canada must also adopt a reverse engineering exception to copyright infringement. It is claimed that the implementation of such an exception is justified through examination of the underlying policy goals of copyright law in the context of an economic framework. Reverse engineering fosters the creation of standards which, it is argued, increase societal wealth. The existence of a reverse engineering exception is consistent with the balance between the economic rights of individual authors and societal technological progress, which copyright seeks to maintain. It is demonstrated that copyright exists as the only form of applicable intellectual property protection which can broadly limit the disclosure of concepts underlying computer programs.
It is suggested that an effective exception should be statutorily based. It is felt that the existing fair dealing exception contained in the Canadian Copyright Act is juridically under-developed and too uncertain to provide an effective solution to the reverse engineering problem. A legislative solution would send a clear message to the software industry as well as to the courts, and could prohibit contracting out of the Copyright Act which would potentially be allowed were a judicial solution sought. It is further suggested that the statutory exception should broadly allow the process of reverse engineering as opposed to limiting it to cases where compatibility is sought. Narrowing the exception creates conceptual difficulties in applying limits to reverse engineering. Allowing a broad exception would avoid these difficulties while continuing to provide copyright holders with protection if, after the reverse engineering process is concluded, their protectable expression is used within another's software product.
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McAdam, Ian. "Connectionist models for reverse engineering". Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=67543.
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Design recovery, a part of the reverse engineering process of a program, must supply a programmer with all the information they need to fully understand a program or a system. In this thesis, a connectionist method is proposed for analyzing the informal information (comments and mnemonics) in a program that can be used for design recovery in conjunction with more traditional approaches. A connectionist model was chosen because of its properties of being robust (capable of tolerating noisy inputs), its associative memory ability (capable of retrieving a concept given only the context of the original input word), and its generalization ability (learn conceptually relevant micro-features of the domain). The proposed approach uses a combination of top down domain analysis (the creation of a concept hierarchy by a domain expert, to be used in the formation of the training set) and a bottom up approach (the analysis of the informal information using the network).
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Wheeler, Graham. "Protocol engineering from Estelle specifications". Doctoral thesis, University of Cape Town, 1993. http://hdl.handle.net/11427/13530.
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Bibliography: leaves 129-132.The design of efficient, reliable communication protocols has long been an area of active research in computer science and engineering, and will remain so while the technology continues to evolve, and information becomes increasingly distributed. This thesis examines the problem of predicting . the performance of a multi-layered protocol system directly from formal specifications in the ISO specification language Estelle, a general-purpose Pascal-based language with support for concurrent processes in the form of communicating extended finite-state machines. The thesis begins with an overview of protocol engineering, and a discusses the areas of performance evaluation and protocol specification. Important parts of the mathematics of discrete-time semi-Markov processes are presented to assist in understanding the approaches to performance evaluation described later. Not much work has been done to date in the area of performance prediction from specifications. The idea was first mooted by Rudin, who illustrated it with a simple model based on the global state reachability graph of a set of synchronous communicating FSMs. About the same time Kritzinger proposed a closed multiclass queueing model. Both of these approaches are described, and their respective strengths and weaknesses pointed out. Two new methods are then presented. They have been implemented as part of an Estelle-based CASE tool, the Protocol Engineering Workbench (PE!V). In the first approach, we show how discrete-time semi-Markov chain models can be derived from meta-executions of Estelle specifications, and consider ways of using these models predictively. The second approach uses a structure similar to a global-state graph. Many of the limitations of Rudin's approach are overcome, and our technique produces highly accurate performance predictions. The PEW is also described in some detail, and its use in performance evaluation illustrated with some examples. The thesis concludes with a discussion of the strengths and weaknesses of the new methods, and possible ways of improving them.
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Malara, Megan Marie. "Engineering the Dermal-Epidermal Junction". The Ohio State University, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=osu1576759637104844.
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Dasgupta, Queeny. "Tailored Xylitol-based Biodegradable Polymers for Tissue Engineering and Drug Delivery". Thesis, 2017. http://etd.iisc.ac.in/handle/2005/4256.
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Tissue regeneration is an intricate physiological phenomenon that involves the interplay of various factors to restore tissue formation and function. Diseased or damaged tissues have often been replaced with synthetic materials such as polymers, metals, ceramics or their composites to facilitate their normal functioning. Polymeric materials such as poly(caprolactone) and poly (lactic-co-glycolic acid) are widely used for engineering matrices for tissue development. However, many of these commercially available materials suffer from drawbacks such as slow degradation and high immune rejection. This necessitates use of immunosuppressive drugs and makes secondary surgery imperative.
The three vital properties of a material that play important roles in controlling cell behaviour are degradation, release and mechanical properties. Developing materials with properties that could appropriately replace the native tissue is a major challenge in this field. The present work focuses on developing a general strategy to develop a library of biodegradable, crosslinked polymers in which these properties can be independently tuned. A rapid screening platform was subsequently engineered to select the correct processing parameters to synthesize materials with tailored compendium of properties. A thermally curable gradient biomaterial was developed as a specific case study. This study further investigated the release of an entrapped drug from the gradient material and opened up a new avenue for developing resorbable materials with degradation-controlled drug release.
Polymer modifications to facilitate drug incorporation are important since implant related infections and inflammatory responses are a major healthcare burden. Thus further, three different generic synthesis strategies were developed to incorporate different anti-inflammatory and antimicrobial drugs onto injectable or implantable polymers. These bioactive materials exhibit high loading of the drug, controlled release and consequent antimicrobial activity. This work provides a basis for the future of tissue engineering by describing tools and strategies for the development of tailored, drug releasing, biodegradable polymers.
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Hillenbrand, Boone S. "An Investigation for the need of Secondary Treatment of Residential Wastewater when Applied with a Subsurface Drip Irrigation System". 2010. http://trace.tennessee.edu/utk_gradthes/716.
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The objective of this study was to investigate the need for domestic wastewater to receive secondary treatment when being applied to the soil by subsurface drip irrigation (SDI). SDI uniformly distributes wastewater into the soil, which optimizes the soil’s chemical, physical, and biological capacity to remove waste constituents. Because of these advantages, many regulatory jurisdictions are allowing SDI at sites that previously were prohibited from using conventional trench-based soil application systems because of shallow soil restrictions. However, most of these regulatory agencies also require that the wastewater receives secondary treatment (dissolved organic carbon reduction) before the SDI system. At issue is whether the enhanced soil-based renovation provided by SDI should eliminate the necessity for secondary treatment before SDI.Two SDI systems were installed and monitored at two sites in Tennessee. These locations were residential developments served by a septic tank effluent pump (STEP) collection system, a recirculating media filter (fine gravel media), and SDI dispersal. At both locations, SDI plots were established to receive primary treated (septic tank effluent) and secondary treated (recirculating media filter effluent) wastewater. In close proximity to randomly selected SDI emitters, soil samples were extracted. Soil cores were analyzed to determine saturated hydraulic conductivity (Ksat), and pore water samples were analyzed for nitrate, total nitrogen, total carbon, and total phosphorus. Results indicate that the primary-treated sites had lower Ksat values, higher nitrate and higher total nitrogen levels than the secondary-treated side and the background soil. Interestingly, the primary treated side had less total carbon and the background phosphorus concentration was twice that of the primary and secondary treated sides. Primary effluent showed a decrease in concentration for all constituents with increased depth. Secondary treatment does result in a higher quality effluent but is not needed when applying effluent with a SDIS.
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Singh, Puneet. "The Role of Basal Ganglia and Redundancy in Supervised Motor Learning". Thesis, 2017. http://etd.iisc.ac.in/handle/2005/4176.
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Human sensorimotor control can achieve highly reliable movements under circumstances of noise, redundancy, uncertainty, and sensory delays. Our ability to achieve reliable and accurate movements is in the fact we have a nervous system that learns these limitations and continuously compensates for them. The purpose of the thesis is to understand brain mechanisms and computations underlying supervised motor learning, its interaction with reinforcement learning and study its relation to motor variability. To address these issues, we have investigated factors influencing supervised motor learning such as neurological disease condition, the role of the reinforcement signal, motor variability and motor redundancy.
Traditionally, supervised or error-based learning and reinforcement or reward based learning are thought to be occurring at anatomically different places and have functionally separate mechanisms. By leveraging the performance of human patients with Parkinson disease and cerebellar ataxia disease, we demonstrate how the presence and absence of dopamine medication and subthalamic deep brain stimulation (STN-DBS) influenced supervised learning. Furthermore, we also show that the presence and absence of reinforcement at the end of the trial profoundly affected learning such that the difference in learning as a consequence of medication reduced significantly. These results suggest that the basal ganglia modulate the gain of supervised learning in the cerebellum based on the reinforcement received at the end of the trial.
Furthermore, we explored motor variability (thought to be an unwanted characteristic of the motor system) and investigated its significance and effect on supervised motor learning. We propose that some part of motor variability arises out of the redundancy in the joints in the human arm. We showed that greater uses of redundancy in the arm lead to faster learning across healthy subjects. We observed these both in dynamic perturbation learning and kinematic perturbation learning. Interestingly, we also found differences in the use of redundancy between the dominant hand and non-dominant hand, suggesting that the nervous system actively controls the redundancy. Furthermore, we also observed some directions in reaching are difficult to learn in comparison to others directions. To understand such behavior, we separated direction wise errors and constructed errors ellipses and found out that eccentricity of ellipse change with learning, which suggests brain while reducing errors in learning, is also trying to homogenize the distribution of errors caused by the perturbation. We also found interesting differences between redundancy and motor learning that was selectively impaired in PD patients but not cerebellar patients, possibly pointing to a role of the basal ganglia in processing of the use of redundancy in motor learning.
In summary, the results in the thesis provide experimental support for the hypothesis that the basal ganglia modulate the gain of supervised learning and exploration of redundancy aids in learning and that the redundancy component of the motor variability is not noise. In future, we hope that this relationship between basal ganglia, reinforcement, and redundancy in supervised motor learning can be leveraged to enhance motor rehabilitation and motor skills in patients with motor deficits.
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Chen, Xi. "Engineering of TEV Protease for Manipulation of Biosystems". Thesis, 2013. http://hdl.handle.net/1807/43517.
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Synthetic biology is a nascent discipline that aims to design and construct new biological systems beyond those found in nature, ultimately using them to probe, control, or even replace existing biological systems. The success of synthetic biology depends on the assembly of a set of well-defined and modular tools. These tools should ideally be mutually compatible, reusable in different contexts, and have minimum crosstalk with endogenous proteins of the subject. The tobacco etch virus protease (TEV protease, TEVp) is a suitable candidate for such a tool due to its unique substrate specificity and high efficiency. Importantly, TEVp is capable of imitating proteolysis, a ubiquitous mechanism in nature for post-translational modifications and signal propagation. Here, TEVp is employed as a self-contained proteolytic device capable of executing biological tasks that are otherwise governed by endogenous proteins and processes. Consequently, the goal of using TEVp for synthetic manipulation of biosystems is achieved. First, a single-vector multiple gene expression strategy utilizing TEVp self-cleavage was created. This approach was used for the robust expression of up to three genes in both bacterial and mammalian cells with consistent stoichiometry. The products can then be individually purified or targeted to distinct subcellular compartments respectively. Second, a temperature-inducible TEVp was created by incremental truncation of TEVp. The 18th truncation of TEVp (tsTEVp) resulted in negligible activity at 37 °C, but retained sufficient activity at 30 °C for rapid processing of its substrates in several mammalian cell cultures. Finally, tsTEVp was applied in the context of other synthetic modules to generate a variety of biological responses. Its versatility was demonstrated as cellular processes including protein localization, cellular blebbing, protein degradation, and cell death were rewired to respond to the physical stimulus of temperature.
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Cumba, Hector J. "Biodegradation of cellulosic spent casing waste from the meat processing industry". 2005. http://digital.library.okstate.edu/etd/umi-okstate-1348.pdf.
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