Department: Food, Agricultural, and Biological Engineering ![[clear]](close-x.png "Remove this limiter")
201 matches in the database.
These are records: 1 - 30.
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1.
Ahmed, Ahmed El-Sayed.
Simulation of Simultaneous Heat and Moisture Transfer in Soils Heated by Buried Pipes.
Degree: PhD, Food, Agricultural, and Biological Engineering, 1980, Ohio State University
► Heating commercial greenhouses during winter appears to be one of the most…
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▼ Heating commercial greenhouses during winter appears to be one of the most promising agricultural uses of the reject heat from power plants. Subsurface soil warming and irrigation has the advantage of raising the soil temperature in the root zone without producing excessive humidity in the greenhouse environment. The different approaches to mathematically describe simultaneous heat and moisture transfer in soils were reviewed. A model was selected to describe subsoil warming and irrigation and its highly nonlinear simultaneous differential equations were solved on a digital computer using finite difference and the Continuous System Modeling Program (CSMP) . The model was verified and validated with extensive experimentation in a greenhouse at Ohio Agriculture Research and Development Center, Wooster, Ohio. Three plots of different soils, sand, Wooster silt-loam, and a peat-vermiculite mixture, were equipped with buried, parallel, plastic pipes heated by warm water in the temperature range of reject heat from the power plants. The pipes were buried 30-cm deep and 30-cm apart. A water table was maintained at 50-cm depth to provide subsurface irrigation. The model was applied to the sand and Wooster silt-loam plots because their pertinent physical properties were available in the literature. It was not applied to the peat vermiculite plot for lack of information on its properties. The mathematical model acurately predicted the transient and steady state temperature and moisture distribution in the test plots. The designed heating system provided a uniform root zone temperature in the ideal range of plant growth and provided up to 30 percent of the total heat requirements of the greenhouse. The moisture levels provided by the subsurface irrigation were above the wilting point in the silt-loam plot for most crops. A shallower water table, 40-cm deep, appeared necessary in the sand plot.
Advisors/Committee Members: Hamdy, M Y.
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2.
Alden, Curtis W.
A stereoscopic image analysis system to locate and characterize nursery plants.
Degree: MS, Food, Agricultural, and Biological Engineering, 1989, Ohio State University
► A stereoscopic image processing system was developed to locate and evaluate nursery…
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▼ A stereoscopic image processing system was developed to locate and evaluate nursery plants. The system was tested and evaluated using narrow upright and cone shaped plants. The information retrieved was a control point, representing the location and the height of the plant, and either the radius or apex angle of the plant. The system detected the edges of a plant in each image, then represented the edges as linear equations using the Hough transform. The control point and secondary feature in each image was determined from the linear equations representing the edges. The data from each image was combined to form the desired three dimensional information.
Advisors/Committee Members: Holmes, Robert G.
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4.
Alhamdan, Abdullah M.
Experimental studies on natural and forced convection around spherical and mushroom shaped particles.
Degree: MS, Food, Agricultural, and Biological Engineering, 1989, Ohio State University
► Heat transfer coefficients (h) between fluids and particles were determined for three…
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▼ Heat transfer coefficients (h) between fluids and particles were determined for three situations: the first two involving natural convection of a mushroom-shaped particle immersed in Newtonian and non-Newtonian liquids, and the third involving continuous flow of a sphere within liquid in a tube. For natural convection studies, h was much higher for heating than for cooling, and decreased with time as equilibration occurred. For the continuous flow studies, h was found to increase with flow rate.
Advisors/Committee Members: Sastry, Sudhir.
Keywords: PARTICLES; Heat transfer; Heat transfer coefficients
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7.
Al-zoheiry, Ahmed M.
Modeling a drip irrigation system powered by a renewable energy source.
Degree: PhD, Food, Agricultural, and Biological Engineering, 2006, Ohio State University
► Food production is a problem in many of the regains in the…
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▼ Food production is a problem in many of the regains in the world. Today, the process of producing food is very dependent on energy. The dependency on fossil fuels causes the cost of producing crops to increase as the prices of fuel increases. Using a renewable energy sources to power an irrigation system is a mean of decreasing the dependency of food products on the prices of fuel and minimize the impact of the irrigation system on the environment. A model was developed to simulate and predict the performance of an irrigation system powered by a renewable energy source. Both solar energy and wind energy were considered for the modeling of the system. The solar energy was simulated using the difference between the maximum and the minimum daily temperatures as an indicator of the amount of clouds in the atmosphere. The model is a modification of earlier models and has the advantage of not needing to be calibrated for each new site. Results showed that a model that calibrates it self for the upper and the lower expected values of the solar radiation can be developed using metrological data such as the location of the site, the daily temperatures, and the minimum relative humidity. ii The wind energy was predicted using the power coefficient of the turbine and statistical representation of the daily wind speeds. The average hourly values of the wind speed were used for finding the distribution constants for the Weibull distribution and Rayleigh distribution. The results showed that the Weibull distribution is more accurate in predicting the expected power output of the turbine when the daily wind speed coefficient of variation (Cv) was less than 0.5. When the Cv is greater than 0.5 the Rayleigh distribution gives better results. A computer model was developed using Visual Basic to model the system and the resulting model was tested and used in comparing the economics of a traditional irrigation system and an irrigation system powered by solar panels. The system powered by the solar panel had a greater total annual cost than the traditional system but the sensitivity analysis performed showed that if the trends in energy prices continue and the prices of the solar panels continue to decrease, the cost for operating the traditional systems will be close to the cost of operating the systems powered by the solar panels in less than a 10 years.
Advisors/Committee Members: Brown, Larry C.
Subjects: Engineering, Agricultural
Keywords: Drip Irrigation; PV solar power; wind energy
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10.
Azimi, Amir H.
Effect of operating parameters on deposition uniformity in broadcast applications.
Degree: MS, Food, Agricultural, and Biological Engineering, 1984, Ohio State University
► In this study, the effect of various operating parameters in broadcast application…
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▼ In this study, the effect of various operating parameters in broadcast application (i.e. nozzle spacing along the boom, pressure, height, and nozzle tilt angle) for various nozzle types and capacities were investigated under laboratory conditions. The results indicated that narrower spacings tend to improve the deposition uniformity and they also create more stable distributions, i.e. the deposition uniformity is less vulnerable to fluctuations in height and pressure when the nozzles are utilized in narrower spacings. The results also showed that higher pressures, larger heights, and tilting the nozzles in a rearward direction generally improved the uniformity.
Advisors/Committee Members: Carpenter, Thomas G.
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11.
Bai, Shuangyi.
Identification And Characterization Of Senescence-Associated Proteins In Petunia Corollas.
Degree: PhD, Food, Agricultural, and Biological Engineering, 2008, Ohio State University
► Senescence is a degenerate process that leads to the death of plant…
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▼ Senescence is a degenerate process that leads to the death of plant cells, organs or whole plants. Senescence is not a passive process, but is an active developmental process regulated by plant age and other internal and external signals. The timing of natural senescence is not only controlled by developmental age, but also influenced by abiotic and biotic stimuli. The main purpose of leaf and petal senescence in plants is to remobilize and recycle nutrients from old and/or no longer necessary organs to developing parts of the plant, such as from senescing leave to young leaves, flowers, fruits and seeds. The quality and subsequent value of both agricultural and horticultural crops is impacted by the senescence of vegetative and floral organs. Therefore, it is of practical importance to understand the molecular and biochemical mechanisms of senescence initiation, regulation and execution. The goal of my project is to identify global protein changes that occur during petal senescence. To this end, I employed two-dimensional polyacrylamide gel electrophoresis (2-DE) based on proteomic approaches to identify protein changes during petunia corolla senescence. One hundred thirty three differentially expressed spots were selected to be sequenced by tandem mass spectrometry. The majority of up regulated proteins were hydrolytic enzymes involved in macromolecular degradation and defense responses to abiotic and biotic stress. Protein sequencing data indicated that a number of proteins were post-translationally modified or processed during senescence. Our results not only support previous transcriptome studies, but also provide new insights into the post-translational regulation of senescence. A senescence-specific nuclease (referrered as to PhNUC2) from our 2-DE results was investigated. PhNUC2 transcripts were specifically induced in senescing flower tissues. We hypothesized that suppression of PhNUC2 activity would delay nucleic acid catabolism during senescence, and this would in turn delay petal senescence. Thus, virus-induced gene silencing (VIGS) was used to knock down PhNUC2 gene expression. PhNUC2 gene expression and PhNUC2 nuclease activity were significantly reduced in VIGS corollas during senescence. However, the flower longevity was not prolonged in VIGS experiments. The reasons are discussed.
Advisors/Committee Members: Jones, Michelle.
Subjects: Horticulture
Keywords: flower senescence, proteomics, 2-DE, senescence-associated gene
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21.
Bhalerao, Kaustubh D.
Characterizing the reliability of a BioMEMS-based cantilever sensor.
Degree: PhD, Food, Agricultural, and Biological Engineering, 2004, Ohio State University
► The cantilever-based BioMEMS sensor represents one instance from many competing ideas of…
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▼ The cantilever-based BioMEMS sensor represents one instance from many competing ideas of biosensor technology based on Micro Electro Mechanical Systems. The advancement of BioMEMS from laboratory - scale experiments to applications in the field will require standardization of their components and manufacturing procedures as well as frameworks to evaluate their performance. Reliability, the likelihood with which a system performs its intended task, is a compact mathematical description of its performance. The mathematical and statistical foundation of systems-reliability has been applied to the cantilever-based BioMEMS sensor. The sensor is designed to detect one aspect of human ovarian cancer, namely the over-expression of the folate receptor surface protein (FR – α). Even as the application chosen is clinically motivated, the objective of this study was to demonstrate the underlying systems-based methodology used to design, develop and evaluate the sensor. The framework development can be readily extended to other BioMEMS-based devices for disease detection and will have an impact in the rapidly growing $30 bn industry. The Unified Modeling Language (UML) is a systems-based framework for design and development of object-oriented information systems which has potential application for use in systems designed to interact with biological environments. The UML has been used to abstract and describe the application of the biosensor, to identify key components of the biosensor, and the technology needed to link them together in a coherent manner. The use of the framework is also demonstrated in computation of system reliability from first principles as a function of the structure and materials of the biosensor. The outcomes of applying the systems-based framework to the study are the following: Characterizing the cantilever-based MEMS device for disease (cell) detection. Development of a novel chemical interface between the analyte and the sensor that provides a degree of selectivity towards the disease. Demonstrating the performance and measuring the reliability of the biosensor prototype, and Identification of opportunities in technological development in order to further refine the proposed biosensor. Application of the methodology to design develop and evaluate the reliability of BioMEMS devices will be beneficial in the streamlining the growth of the BioMEMS industry, while providing a decision-support tool in comparing and adopting suitable technologies from available competing options.
Advisors/Committee Members: Soboyejo, Alfred B.O.
Keywords: BioMEMS; Cantilever sensor; Reliability; UML
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26.
Chan, Chee-Wan.
Effects of powered harrow operating parameters on soil physical properties.
Degree: MS, Food, Agricultural, and Biological Engineering, 1992, Ohio State University
► The choice of field operating parameters of a powered harrow has a…
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▼ The choice of field operating parameters of a powered harrow has a pronounced effect on the final seedbed conditions. The effects of rotary velocity over tractor forward speed (λ), shape of blade, tractor tire traffic and blade overlap intensity on soil physical properties were assessed. Computer graphics kinematic analysis on the rotary blade's path was used to locate the different tilled zones for evaluation. Field test results indicated a significant main effect of λ and the interaction effects of blade type, tire traffic and blade overlap intensity. Measurements of air porosity, air permeability, dry bulk density and soil strength, were made by an automated Soil Physical Properties Measurement System.
Advisors/Committee Members: Wood, Randall K.
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27.
Chaoui, Hala I.
Separating earthworms from organic media using an electric field.
Degree: PhD, Food, Agricultural, and Biological Engineering, 2005, Ohio State University
► Earthworms have been shown to effectively process biodegradable organic waste and increase…
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▼ Earthworms have been shown to effectively process biodegradable organic waste and increase the its level of available plant nutrients to plants. Earthworms are typically mechanically separated from the finished product. This study investigated the effectiveness of an electric field at separating earthworms from an organic media by repelling them. Results showed that the effectiveness of an electric field at repelling earthworms is a function of the voltage created across earthworms, which in turn is a function of electrode depth, spacing, earthworm species (and resulting diameter and resistance) and electric current level at the threshold beyond which earthworms are repelled. Each factor was shown to significantly affect the effectiveness with which earthworms were repelled. This was concluded from experiments where earthworms were placed in a soil slab at a density corresponding to 150 earthworms per liter, and effectiveness of the electric field was calculated as a function of the number of earthworms that exited the soil slab. Results showed that the effectiveness of the electric field was logarithmically proportional to the voltage generated across earthworms, at a given electrode spacing, up to the point of mortality onset. At higher voltages the electric field effectiveness decreased exponentially due to mortality. The time where all potential earthworms exited a soil slab increased exponentially up to peak effectiveness, and decreased exponentially after that. Testing the derived model showed that it applies to any soil type, since results showed that soil properties including salinity, moisture content and porosity are accounted for by soil resistance, which is used to calculate the electric current term in the model. A comparison between alternating and direct current showed an increased effectiveness of the model when alternating current was used. A model of electric current diffusion in earthworm casts suggested that at increasing voltage levels, the distance from the electric field at which an optimal electric current level can be found converges to a single value. The mathematical models derived from this study can be used for the preliminary design of an electric earthworm separator consisting of an array of current-conducting rods connected to a power or voltage source.
Advisors/Committee Members: Keener, Harold M.
Subjects: Engineering, Agricultural
Keywords: earthworms, electricity, electric field, separation, vermicomposting, organic fertilizer, mathematical model, voltage, current, diffusion.
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