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Full-Text Articles in Life Sciences

Project Oasis: Optimizing Aquaponic Systems To Improve Sustainability, Siddharth Nigam, Paige Balcom Jan 2016

Project Oasis: Optimizing Aquaponic Systems To Improve Sustainability, Siddharth Nigam, Paige Balcom

Honors Theses and Capstones

Started in Fall 2015, Project OASIS (Optimizing Aquaponic Systems to Improve Sustainability) is an interdisciplinary capstone project with the goal of designing a sustainable and affordable small-scale aquaponic system for use in developing nations to tackle the problems of malnutrition and food insecurity. Aquaponics is a symbiotic relationship between fish and vegetables growing together in a recirculating system. The project’s goals were to minimize energy consumption and construction costs while using universally available materials. The computational fluid dynamics (CFD) software OpenFOAM was used to create transient and steady-state models of fish tanks to visualize velocity profiles, streamlines, and particle ...


The Transfer Of Agricultural Water To Municipal And Industrial Usages, Dallin Paul Stephens May 2011

The Transfer Of Agricultural Water To Municipal And Industrial Usages, Dallin Paul Stephens

All Graduate Theses and Dissertations

The water that is available for beneficial use in Utah is quickly approaching full appropriation; water that has been claimed is nearing the amount that is available for use. The Division of Water Resources of the State of Utah has organized a three-part plan to "Plan, Conserve, Develop and Protect Utah's Water Resources." One of these three elements has a focus to "provide comprehensive water planning." Such planning is best achieved when current and accurate data on the uses of the state's water are available.

The primary purpose of this thesis was to provide an evaluation, from data ...


Vegetative Filter Strip Assessment In The State Of Iowa, Manveen Bansal Jan 2006

Vegetative Filter Strip Assessment In The State Of Iowa, Manveen Bansal

Retrospective Theses and Dissertations

Vegetative filter strips (VFS) is one of the best management practices that uses natural processes to remove a portion of the sediment and other pollutants carried by runoff before the water enters a water-body. The project analyzes the flow accumulation of runoff with the help of Geographic Information Systems (GIS). The objectives for this project include (1) To determine the effectiveness of VFS by visual field observation and validation by flow mapping procedures in ArcGIS 9, (2) To compare the area ratios and percentage of flow along each stream segment at various resolutions for different sizes of the survey data ...


Hydrological Modification Of Subsurface Drainage Systems , Kyle Dean Riley Jan 2006

Hydrological Modification Of Subsurface Drainage Systems , Kyle Dean Riley

Retrospective Theses and Dissertations

Controlled Drainage (CD), a subsurface drainage management system, has been researched in many regions. Previous research has reported CD to reduce subsurface drainage and as a result reduce nitrate loading. CD has been reported to have little effect on nitrate concentrations, so exploring alternative treatments to reduce these concentrations would be constructive. This research was intended to measure the effect of CD on surface runoff, crop yield, water table depth, and to document a biofilter's effect on nitrate concentrations. CD increased surface runoff ranging from 53% to 130%, increased corn yield by 14% over two years, and decreased nitrate ...


Integration Of Remote Sensing And Crop Growth Modeling For Nitrogen Management Decision Support In Corn , Kelly Robert Thorp Jan 2006

Integration Of Remote Sensing And Crop Growth Modeling For Nitrogen Management Decision Support In Corn , Kelly Robert Thorp

Retrospective Theses and Dissertations

This dissertation describes efforts to move toward a completely integrated remote sensing and crop growth modeling tool for developing precision nitrogen management recommendations for corn. Aerial hyperspectral remote sensing imagery collected throughout the 2004 growing season was used to estimate corn plant stand density, and a machine vision system was used to map corn population on the ground. Multiple linear regression analysis was used to assess the ability of all combinations of three reflectance bands to estimate corn plant population at resolutions of 2 m, 6 m, and 10 m. Coefficients of multiple determination of up to 0.82 were ...


Analysis Of The Influence Of Soil Temperature And Soil Surface Conditions On Soil Moisture Estimation Using The Theta Probe , Geetika Dilawari Jan 2006

Analysis Of The Influence Of Soil Temperature And Soil Surface Conditions On Soil Moisture Estimation Using The Theta Probe , Geetika Dilawari

Retrospective Theses and Dissertations

Soil moisture is an important component of numerous systems, influencing crop development, and runoff and infiltration partitioning, among other things. However, due to its spatial and temporal variability, it is difficult to estimate soil moisture consistently using conventional techniques such as gravimetric sampling, which is point-based and time-consuming. Therefore, to overcome this drawback in soil moisture estimation and mapping, and to facilitate its measurement spatially and temporarily, remote sensing in microwave, visible, near infrared and short wave infrared is being explored and is proving to be a promising technique. But to develop models using spectral data there is a need ...


Design And Development Of Grainnet - Universal Internet Enabled Software For Operation And Standardization Of Near-Infrared Spectrometers , Robert Dzupin Jan 2005

Design And Development Of Grainnet - Universal Internet Enabled Software For Operation And Standardization Of Near-Infrared Spectrometers , Robert Dzupin

Retrospective Theses and Dissertations

A current trend in modern near-infrared spectroscopy is the incorporation of sophisticated mathematical algorithms into the computer instrumentation used to extract information from raw spectral data by applying complex multivariate models. To address some of the problems that near-infrared spectroscopy faces, the GrainNet software model that connects a MATLABRTM computing and development environment, NIR spectrometers, and MS Server data-storage for spectral data and calibration models, was developed.;GrainNet is a client-server based Internet enabled communication and analyzing model for Near-Infrared (NIR) instruments. FOSS Infratec, Perten, and Bruins Instruments are currently three brands of the NIR instruments that have been included ...


Effectiveness Of Solids Removal From Liquid Swine And Dairy Manures Using Biomaterial Filtration , Mark Vincent Garrison Jan 2005

Effectiveness Of Solids Removal From Liquid Swine And Dairy Manures Using Biomaterial Filtration , Mark Vincent Garrison

Retrospective Theses and Dissertations

Recently, the livestock industry in the United States has been under scrutiny of environmental policymakers and the general public in regards to the industry's impact on the environment. This has forced the livestock industry to be more conscious in the handling, treatment, and disposal of manures produced by confinement animals. The management of animal waste typically involves several steps, but due to low production profit margins and the demand for technological simplicity, animal manures tend to have less treatment than human wastes. Liquid-solid separation using biomaterials, like corn stover, offers a possible cheap and technologically simple alternative for waste ...


Using Surface Solute Transport Properties Measured By Time Domain Reflectometry To Predict Subsurface Leaching , Anju Gaur Jan 2004

Using Surface Solute Transport Properties Measured By Time Domain Reflectometry To Predict Subsurface Leaching , Anju Gaur

Retrospective Theses and Dissertations

Solute transport properties are required to evaluate the risk of contaminating ground water with agricultural chemicals under a wide variety of crop and soil management practices. Most solute transport measurement techniques are tedious and lead to extensive soil excavation. Two experiments were performed to evaluate whether surface transport properties determined by a non-destructive time domain reflectometry (TDR) technique could be used to accurately predict subsurface leaching. TDR probes installed in the surface 2-cm of soil were used to determine resident solute concentration from measured soil surface soil bulk electrical conductivity. Resident concentrations were analyzed with a one-dimensional (1-D) solute transport ...


Development Of Real-Time Electro-Pneumatic Soil Sampler , Saadettin Yildirim Jan 2003

Development Of Real-Time Electro-Pneumatic Soil Sampler , Saadettin Yildirim

Retrospective Theses and Dissertations

An Automated Electro-Pneumatic Soil Sampling (EP) method based on pressurized air for real time soil analysis was developed and tested in laboratory conditions. Pressurized air was applied for 36 milliseconds across a 3 cm diameter cylinder to cut a soil column and convey soil along a delivery pipe into a container. An electro-pneumatic regulator valve was used to regulate the air pressure at 550, 690, and 830 kPa using an analog electrical signal. A two-position solenoid valve controlled by a stand-alone microprocessor was used to control pulse duration. The effects of air pressure level, soil moisture content, soil compaction, and ...


A Real Time Imaging System For Assessment And Control Swine Thermal Comfort , Bin Shao Jan 2003

A Real Time Imaging System For Assessment And Control Swine Thermal Comfort , Bin Shao

Retrospective Theses and Dissertations

A real-time bioimaging system was developed to detect movement of group-housed pigs and to classify thermal comfort state of the pigs based on their resting patterns. This dissertation describes the background, theory, image features selection and analysis, image classification techniques, system architecture, and system performance with artificial and live pigs.;The system is based on the bioimaging control method: using animal's thermal behavior as the ultimate biosensor that is used to reflect animal thermal comfortable levels. An automated real time image processing and control system is developed that monitors animal behavior and adjusts external devices according to the image ...


Application Of Near-Infrared Spectroscopy For Determination Of Nutrient Contents In Manure , Wenyu Ye Jan 2003

Application Of Near-Infrared Spectroscopy For Determination Of Nutrient Contents In Manure , Wenyu Ye

Retrospective Theses and Dissertations

111 solid poultry layer, 95 solid poultry broiler litter, 39 swine solid hoop, 72 beef cattle, 85 swine slurry, and 88 swine liquid lagoon manure samples were collected from farms in three states. Samples were analyzed for total nitrogen (TN), ammonia nitrogen (NH3-N), phosphorus (P), and potassium (K) and total solids (TS) by traditional laboratory methods. The strong relationships of TN, NH3-N, P and K with TS were only found for K in swine lagoon manure and for P in swine slurry. Further, poor prediction performance was found in regression lines even with a strong relationship by using the ratio ...


Designing, Modeling, And Testing A Solar Water Pump For Developing Countries , Abdalla M. Kishta Jan 2002

Designing, Modeling, And Testing A Solar Water Pump For Developing Countries , Abdalla M. Kishta

Retrospective Theses and Dissertations

Egypt has very limited surface water resources, perhaps surprisingly the country has quite plentiful water available from shallow wells. If water could be lifted from these wells, much more of the country could be used for growing crops.;Lack of capital investment and expense of fossil fuels has limited Egypt's ability to use subsurface water. On the other hand, Egypt is ideally situated for using solar Oil, Gas, and Energy;The project has designed a system for pumping water using very few moving parts. A solar collector heats a stream of water to 2 bar abs. This stream is ...


Using Radio Frequency Spectral Measurements For Determination Of Corn Mechanical Damage , Majdi Ali Al-Mahasneh Jan 2001

Using Radio Frequency Spectral Measurements For Determination Of Corn Mechanical Damage , Majdi Ali Al-Mahasneh

Retrospective Theses and Dissertations

Dielectric measurements between 10 Hz to 13 MHz were obtained using an HP 4192A Impedance Analyzer for artificially damaged and combine damaged corn samples. For medium and severe artificial damage, the measurements were obtained at two moisture contents (11 and 19 percent), five damage levels (0, 10, 25, 50, and 100 percent), and two bulk densities. The results showed that dielectric properties were able to measure moisture content, bulk density, and mechanical damage level. Using a four-variable model, medium damage level was predicted with R2 = 0.95 and RMSE = 8.8 percent, while severe damage level was predicted with R2 ...


Integrated Spatial Decision Support System For Precision Agriculture , Xixi Wang Jan 2001

Integrated Spatial Decision Support System For Precision Agriculture , Xixi Wang

Retrospective Theses and Dissertations

Excessive application of plant nutrients and pesticides on agricultural land has resulted in both environmental degradation and economic loss to the farming community. Agricultural non-point source pollution was cited as the primary source of the water quality problems in many areas of the United States. Environmental concerns resulting from agricultural non-point source pollution has placed demands on farmers and ranchers to implement the best management practices (BMPs) to reduce the delivery of pollutants to streams and aquifers. Precision agriculture, a relatively recent crop production and agricultural management strategy holds great promise to minimize environmental pollution while to maximize economic productivity ...


Analysis Of Spatial Yield Variability And Economics Of Prescriptions For Precision Agriculture: A Crop Modeling Approach , Joel Obien Paz Jan 2000

Analysis Of Spatial Yield Variability And Economics Of Prescriptions For Precision Agriculture: A Crop Modeling Approach , Joel Obien Paz

Retrospective Theses and Dissertations

Non-uniformity of soil properties, soil moisture and rooting depth, and other factors such pest and disease pressures can cause significant soybean and corn yield variability within a field. In this study, two crop growth models were used to characterize factors that cause spatial yield variability in soybeans and corn, and to evaluate economic consequences of variable rate management prescriptions. Analysis of yield data from 224 grids within a 16-hectare field in Boone, Iowa focused on water stress effects using CROPGRO-Soybean and CERES-Maize models for soybean and corn, respectively. Water stress explained 69% of the variability in soybean, and population and ...


Evaluation Of Yield Sensors For Site-Specific Management , Selcuk Arslan Jan 2000

Evaluation Of Yield Sensors For Site-Specific Management , Selcuk Arslan

Retrospective Theses and Dissertations

The performance of an impact-based yield monitor was investigated via field and laboratory experiments. In another study, X-ray techniques were used to examine the potential use of x-rays for yield measurements of harvested crops. Field and laboratory experiments showed that proper yield sensor calibration is the most important factor to keep the error less than +/-4% when individual grain tank loads are considered. Field and laboratory tests provided evidence of decreasing error with increasing harvest area. In field tests, the accuracy of yield monitors increased consistently when yield measurements were averaged over 15, 30, and 60 m long segments, respectively ...


Herbicide And Conservative Tracer Movement Through The Soil Profile And To Subsurface Drains Under No-Till And Chisel Plow Systems , Syed Imran Ahmed Jan 1999

Herbicide And Conservative Tracer Movement Through The Soil Profile And To Subsurface Drains Under No-Till And Chisel Plow Systems , Syed Imran Ahmed

Retrospective Theses and Dissertations

Adoption of conservation tillage has increased the role of macropore flow on the transport of agricultural chemicals to groundwater. Therefore, it is important to understand the role of macropore flow in the transport of water through the vadose zone and to the shallow groundwater. Two field studies were conducted at Iowa State University's Agricultural Research Center near Boone, Iowa, to determine the effect of two tillage practices (chisel plow and no-till) on the transport of herbicides and tracers, with applied water, through the soil profile and to the shallow groundwater. Two herbicides, atrazine [(6-chloro-N-ethyl-N-(1-methylethyl-1,3,5 triazine)-2-4-diamine ...


A Probabilistic Neural Network Computer Vision System For Corn Kernel Damage Evaluation , Loren W. Steenhoek Jan 1999

A Probabilistic Neural Network Computer Vision System For Corn Kernel Damage Evaluation , Loren W. Steenhoek

Retrospective Theses and Dissertations

An investigation was conducted to determine whether image processing and machine vision technology could be used for identification of the damage factor in corn kernels. Prominent types of corn kernel damage were found to be germ damage and blue-eye mold damage. A sample set containing 720 kernels with approximately equal numbers of blue-eye mold-damaged, germ-damaged, and sound kernels was obtained and evaluated by human inspectors and the computer vision system. While the computer vision system developed was slightly less consistent in classification than trained human inspectors, it did prove to be a promising step toward inspection automation;Two probabilistic neural ...


Use Of Site Specific Farming Systems And Computer Simulation Models For Agricultural Productivity And Environmental Quality , Allah Bakhsh Jan 1999

Use Of Site Specific Farming Systems And Computer Simulation Models For Agricultural Productivity And Environmental Quality , Allah Bakhsh

Retrospective Theses and Dissertations

Site specific farming systems have the potential to increase farmers' net income by reducing the use of agro-chemicals and applying variable rate technology for areas showing stable yield patterns. This study was designed to: (1) study yield patterns in given fields using variography; (2) seek correlation among soil attributes and yield data using GIS; and (3) simulate the effects of N-fertilizer and swine manure application rates on NO 3-N losses with subsurface drainage water and crop yields. The results of this study showed that the spatial correlation lengths were found to vary from 40 m for corn to about 90 ...


Assessment And Simulation Of Atrazine As Influenced By Drainage And Irrigation: An Interface Between Rzwqm And Arcview Gis , Ana Sofia De Oliveira Nobre Azevedo Jan 1998

Assessment And Simulation Of Atrazine As Influenced By Drainage And Irrigation: An Interface Between Rzwqm And Arcview Gis , Ana Sofia De Oliveira Nobre Azevedo

Retrospective Theses and Dissertations

Atrazine is the most frequently detected herbicide in groundwater. For these reasons, atrazine's dynamics need to be studied, and work is needed to develop and calibrate mathematical models to help in determining best management practices to minimize contamination. This study was designed to make a small contribution in solving some of the environmental related problems;In the first part of this study, macroporosity of an agricultural soil in Iowa was characterized. This study confirmed that under saturated and partially saturated flow conditions, macropore flow was a dominant mechanism for water and chemical transport;Atrazine's movement through the soil ...


Behavior-Based Assessment Of Thermal Requirements Of Piglets From Birth To Weaning , Hongsen Zhou Jan 1998

Behavior-Based Assessment Of Thermal Requirements Of Piglets From Birth To Weaning , Hongsen Zhou

Retrospective Theses and Dissertations

A one-year field study compared the conventional 250W IR heat lamp with an energy-efficient 175W radiant heat lamp for swine farrowing operations. The results indicate that the energy-efficient heat lamp showed a 36 annual cash savings per heat lamp (@ 0.10/kWh); a 1.2% absolute reduction in birth-to-wean piglet mortality (5.0% vs. 6.2%); a 45% lower lamp failure rate (18% vs. 32%); and a slightly higher piglet rate of gain (217 g/day vs. 211 g/day);Investigation of a discrete-sampling, photographic method indicated that a sampling interval of up to 60 minutes would be adequate for ...


Impacts Of Preplant Tillage And Tracer Application Method On Preferential Flow To Groundwater , William Lawrence Kranz Jan 1998

Impacts Of Preplant Tillage And Tracer Application Method On Preferential Flow To Groundwater , William Lawrence Kranz

Retrospective Theses and Dissertations

Eight, one-meter cubic soil monoliths were collected from research plots with 15 years of tillage and crop rotation history. Tillage practices, arranged in a randomized complete block with three replications, were chisel plow, moldboard plow, and ridge tillage. The plots were part of a soybean-corn crop rotation with corn planted the previous year. A test stand was developed that allowed water application using a hypodermic needle style applicator, and collection of leachate using a grid of fiberglass wick extractors. Three anion tracers were applied to simulate nitrogen application by surface broadcast, slot with surface compaction, and with water. Water applications ...


Design Of A Tractor Guidance System Using Simulation Trajectory Results Of Multibody Dynamic Program "Dads" , Elniema Mordos Moslim Jan 1997

Design Of A Tractor Guidance System Using Simulation Trajectory Results Of Multibody Dynamic Program "Dads" , Elniema Mordos Moslim

Retrospective Theses and Dissertations

Recent trends in agricultural industry indicate that automatic guidance of agricultural machines is indispensable for precision farming. The purpose of automatic guidance is to make the machine follow a prescribed path. A successful guidance system must be able to control the position of the machine to within a few centimeters;This study used two of the powerful software for design and analysis of mechanical and control systems, DADS and MATLAB. Also a Fortran code was written for the purpose of PMF system identification;First, DADS was used to model and perform tractor dynamic analysis. DADS animation feature was utilized to ...


Soybean Quality Loss During Constant Storage Conditions , Ibni Hajar Rukunudin Jan 1997

Soybean Quality Loss During Constant Storage Conditions , Ibni Hajar Rukunudin

Retrospective Theses and Dissertations

A modified method for determining free fatty acid (FFA) in crude and refined soybean oils from 0.3 to 6.0 g oil sample size was developed. Good correlation between the modified and official methods was established for crude and refined soybean oils with R2 of 0.9995 and 0.997, respectively. The slopes were 1.01 and 0.99 for the crude and refined oil, respectively.;The number of days soybean lost 0.5 and 1.0% dry matter, for low and high harvest moisture content (MC) soybeans both mechanically and manually harvested, were determined. Soybeans manually harvested at ...


Comparing Rolling Coulters Based On Soil Disturbance , Ravindra Dattatray Godbolé Jan 1997

Comparing Rolling Coulters Based On Soil Disturbance , Ravindra Dattatray Godbolé

Retrospective Theses and Dissertations

Rolling coulters are widely used as a leading element on modem conservation till planters. Few studies have predicted or measured how coulters interact with the soil and what soil conditions they create. This research was initiated to study and compare popular rolling coulter designs; bubble, plain, 8-wave and 25-wave, based on the soil disturbance they cause. Soil disturbance was measured in terms of surface disturbance using a photoscanning technique, surface roughness using soil profiles, and strength changes using cone index profiles. Testing was conducted in rototilled and no-till clay loam, and in compacted and loose clay and sandy soils. Soil ...


Classification Of Swine Thermal Comfort Behavior By Image Processing And Neural Network , Junqing Shao Jan 1997

Classification Of Swine Thermal Comfort Behavior By Image Processing And Neural Network , Junqing Shao

Retrospective Theses and Dissertations

In confinement swine production, environment controllers have conventionally been using air temperature as the standard, single control variable. Although the air temperature may be precisely controlled as designed, this method has its inherent drawbacks of not being interactive with the thermal needs of the pigs. Better performance of the animals may be achieved if the control is directly based on their thermal comfort behavior, which is not only affected by air temperature, but also by other thermal, social, and nutritional factors--floor type, air velocity, radiation, group size, etc;An interactive, behavior-based control scheme was thus proposed in this dissertation. This ...


Air Mixing Criteria For Ceiling Slot-Ventilated Agricultural Enclosures , Hsin Yu Jan 1996

Air Mixing Criteria For Ceiling Slot-Ventilated Agricultural Enclosures , Hsin Yu

Retrospective Theses and Dissertations

The use of a scale-model is an effective technique to predict the performance of ventilation in full-scale prototypes. Many criteria have been proposed to simulate the behavior of airflow between scale-model and prototype. Because of the inconsistent results of past proposed similarity criteria, more validation work is needed to clarify the conflicts;Dimensional analysis using both the Buckingham Pi method and manipulating the governing differential equations was used to theoretically establish similarity parameters. Only partial similarity was reached since conflicts exist between proposed similarity parameters;Experiments of two scale models were conducted to study airflow similarity in ceiling slot-ventilated agricultural ...


Fate Of Nutrients From Liquid Swine Manure Land-Applied In The Winter , Jeffery Clark Lorimor Jan 1996

Fate Of Nutrients From Liquid Swine Manure Land-Applied In The Winter , Jeffery Clark Lorimor

Retrospective Theses and Dissertations

The effect of winter liquid swine manure applications on the quality of surface runoff from snowmelt was studied. Manure was applied to corn stubble and soybean stubble plots with a 2.9% slope. Four treatments were used: fall incorporation, early winter broadcast on frozen soil, late winter broadcast on top of snow, and spring broadcast. Nutrient applications averaged 257 kg/ha of kjeldahl nitrogen, and 54 kg/ha total phosphorus per application. Variations in the application rates by date were high due to nonuniformity of the manure used, and tended to increase from fall to spring;In the two-year study ...


Knowledge And Decision Support For Variable Rate Application Of Materials In Prescription Farming , Jack Robert Ambuel Jan 1995

Knowledge And Decision Support For Variable Rate Application Of Materials In Prescription Farming , Jack Robert Ambuel

Retrospective Theses and Dissertations

One major goal of prescription farming is to optimize application rates for seed fertilizer, and other agricultural inputs as a function of location within a field. There are four main components of a variable rate application system: (1) A method of determining the location of farm equipment (e.g. combines, tractors) within a field. (2) A system for controlling the application rate of materials (seeds, fertilizers, pesticides). (3) The capability to measure the results using a real time yield monitor. (4) An algorithm or prescription for determining what rates of materials to apply at each location. In this dissertation it ...