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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

The development of a conceptual benchmarking tool representing big data and agricultural technology adoption on the farm

Maurer, Jacob Lafe January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Gregory Ibendahl / One of the latest buzzes amongst agriculture is the storage and analysis of “Big Data.” There are a number of questions surrounding the quality, quantity, and capacity of big data to form real-world decisions based upon past information. Much like the teachings of history, the storybook that big data can reveal about a grower’s operation may hold the answers to the question of: “what is necessary to increase food production which will be required to feed an ever-growing world?” With the increase in interest in precision agriculture, sustainability practices, and the processing of the immense spatial dataset generated on the farm, the next challenge at hand will be in determining how to make technology not only streamlined, but also profitable. Over the past few years, precision agriculture technology has become widely adopted as an agronomic decision making tool. Much like a scientific experiment, the greater the number of similar observations, the greater the degree of confidence can be placed upon a decision. As a means of increasing the number of observations that a farmer can use to base a decision upon, there is becoming increasing demand in being able to combine the data of similar farming operations in order to increase the size and scope of the dataset to generate better decisions benefitting many farms instead of just one. The growing interest in forming community data pools for farm data demonstrates the need for a study for determining how farming practices can be properly benchmarked. The goal was be to evaluate how to use farm data to make economic decisions in a similar manner as one would make agronomic decisions using similar observations. The objective was to design the proper protocol for benchmarking the farm’s potential, and evaluating potential increases in technical efficiency by adopting precision agriculture technology. To accomplish this, a data envelopment analysis was conducted using scale efficiency as a means of determining the frontier of efficient farms. The resounding goal for this study in the future will be to use the model as a means of implementing the secondary process of pooling precision agriculture data to analyze efficiencies gained by the adoption of technology. By demonstrating the value of generating peer groups to increase observations and refine farming practices, farmers can find increased profitability and efficiency by using resources that may already be held within the operation.
202

Assessing environmental equivalents for water quality trading

Lee, Ming-Chieh January 1900 (has links)
Doctor of Philosophy / Department of Biological & Agricultural Engineering / Kyle R. Douglas-Mankin / Water quality trading (WQT) is a market-based approach to improve water quality. It is an innovative, voluntary program that connects point source (PS) dischargers who need to reduce their pollutant loads with land managers who could offset those loads with nonpoint source (NPS) reductions to economically achieve water quality improvements in a watershed. The potential issues impeding WQT are its inability to address trading risks and quantify the uncertainty of potential load reduction in trades between PS and NPS. Recent research has also shown that trading information level and transaction costs cause problems in implementing WQT. Therefore, the goals of this study were to quantify the uncertainties of pollutant load reduction and delivery effect for potential trades, to estimate their spatiotemporal variations, and to provide information for stakeholders to reduce intangible costs of WQT. This study simulated agricultural cropland with more than 225 alternative land management practices to identify trends among these scenarios. Both total nitrogen and total phosphorus loads were modeled with SWAT and EUTROMOD for 36 years to analyze the potential load reduction, in-field uncertainty ratio, in-stream delivery ratio, and overall trading ratio (TR) in Lower Kansas watershed, Kansas. The analyses of site-specific effects in both geospatial and temporal aspects were also applied on subbasin level. The variant loading patterns and time distributions of each subbasin showed strong site-specific phenomena. The ANOVA of in-field nutrient load showed significant differences among the design criteria of scenarios. The results also showed a significant delivery and lake effects within the subbasins. The overall TR ranged from 1 to 2.2 or more in different scenarios. The advanced cluster analysis presented a potential method to eliminate the problems involved in fixed TRs while keeping the method simpler than finer-resolution floating TR system. Based on WQT geospatial data model, a three-tier GIS-based web interface Water Quality Trading Information Platform System (WQTIPS) was then developed for WQT information and assessment. A case study demonstrated WQTIPS can provide systematic, spatially information for stakeholders to assess the potential environmental benefit changes from the land management shifts using a simple interface. This study demonstrated that it is possible to automate water-quality trades, use watershed models to minimize trading risk and maximize water-quality benefits, and prioritize among possible trades both spatially and by BMP.
203

La guerre américaine au Vietnam dans l'historiographie française des années 1960-1970 et 1990-2000

Desjardins, Léa 12 1900 (has links)
Le mémoire historiographique qui suit a comme sujet principal l’étude de l’évolution des perceptions françaises sur l’implication américaine au Vietnam. Nous nous sommes basés sur l’historiographie de deux périodes distinctes, soit celles des années 1960-1970 et 1990-2000. L’objectif était de voir s’il y a eu une transformation du regard que portent les auteurs sur l’implication américaine et, si oui, quelles en sont les causes. Le travail est construit de façon thématique et se divise en trois chapitres. Le premier aborde le choix et l’ampleur des armes utilisées, le second se penche sur la notion du communisme et de la démocratie, et le dernier traite de la conception de l’impérialisme et du colonialisme. Pour tous les thèmes examinés, nous résumons la perception qui ressort de chacun des auteurs afin de comparer les tendances idéologiques propres aux deux périodes étudiées. Nous conclurons qu’il s’est effectivement produit une importante transformation des perceptions. Cette transformation se traduit par une approche de moins en moins critique envers l’implication américaine au Vietnam. Dans chaque chapitre, nous avons pu soulever des causes de changement propres au sujet abordé. Toutefois, une tendance générale et sous-jacente se dégage et s’avère des plus révélatrices, soit le glissement en France des valeurs politiques et morales de la gauche vers la droite, doublé d’un rapprochement idéologique avec les États-Unis. / The main topic of this historiographical thesis is the evolution of French perceptions on American involvement in Vietnam. We based our study on the historiography of two distinctive periods, those spanning from 1960-1970 and 1990-2000. The aim was to see whether there has been a real transformation in writers’ views on American involvement and, if so, what were the causes. The work is constructed thematically and is divided into three chapters. The first addresses the choices and the magnitude of the weapons used, the second examines the concept of communism and democracy, and the third deals with the notion of imperialism and colonialism. For all themes analyzed, we summarized the perception that emerges from each of the authors in order to compare the ideological tendencies of the two specific periods. We have concluded that there has indeed been a significant transformation of perceptions. This transformation has resulted in a less critical attitude towards American involvement in Vietnam. In each chapter, we have been able to observe specific causes of change. However, an underlying tendency emerges and is more revealing, namely the drift of France’s political and moral values from left to right, coupled with an ideological reconciliation with the United States.
204

Analysis of a pilot-scale constructed wetland treatment system for flue gas desulfurization wastewater

Talley, Mary Katherine January 1900 (has links)
Master of Science / Department of Biological and Agricultural Engineering / Stacy L. Hutchinson / Coal-fired generation accounts for 45% of the United States electricity and generates harmful emissions, such as sulfur dioxide. With the implementation of Flue Gas Desulfurization (FGD) systems, sulfur dioxide is removed as an air pollutant and becomes a water pollutant. Basic physical/chemical wastewater treatment can be used to treat FGD wastewater, but increased regulations of effluent water quality have created a need for better, more economical wastewater treatment systems, such as constructed wetlands. At Jeffrey Energy Center, north of St. Mary’s, KS, a pilot-scale constructed wetland treatment system (CWTS) was implemented to treat FGD wastewater before releasing the effluent into the Kansas River. The objectives of this study were to 1.) determine if a portable water quality meter could be used to assess water quality and track pollutant concentrations, 2.) develop a water balance of the CTWS, 3.) generate a water use coefficient for the CWTS, and 4.) create a mass balance on the pollutants of concern. Water quality measurements were taken with a HORIBA U-50 Series Multi Water Quality Checker and compared to analytical water tests provided by Continental Analytic Services, Inc. (CAS) (Salina, KS). The water balance was created by comparing inflows and outflows of data determined through flow meters and a Vantage Pro2™ weather station. Information from the on-site weather station was also used to compute the system water use coefficient. Water sampling was conducted from date to date at 10 locations within the CWTS. In general, there was little to no relationship between the HORIBA water quality measurements and the analytical water tests. Therefore, it was recommended that JEC continue to send water samples on a regular basis to an analytical testing laboratory to assess the CWTS function and track pollutants of concern. Because the water balance was conducted during system initiation, there was a great deal of fluctuation due to problems with the pumping system, issues with the upstream FGD treatment system, extreme weather events, and immature vegetation. This fluctuation resulted in the system having a non-steady state operation, which weakened the ability to calculate a system water use coefficient. However, during periods of strong system function, the water use coefficient was similar to previous studies with maximum water use being approximately equal to the reference evapotranspiration. The results of the mass balance indicated high removals mercury, selenium, and fluoride, but low removals of boron, manganese, chloride, and sulfate were exported from the CWTS.
205

The potential of canola protein for bio-based wood adhesives

Hale, Kristen January 1900 (has links)
Master of Science / Department of Biological and Agricultural Engineering / Donghai Wang / Currently, the majority of adhesives used for wood veneer, plywood, and composite applications are formaldehyde-based. Formaldehyde is derived from petroleum and natural gas, making it non-renewable and toxic. Therefore, extensive research has been conducted to develop bio-based adhesives to replace formaldehyde-based adhesives. Soy protein has shown great potential to partially replace formaldehyde adhesives, and canola protein has similar properties to soy protein. However, little research has been conducted on the feasibility of using canola protein for wood adhesive applications. The objective of this research was to study the adhesion performance of canola protein. Canola protein was modified with different chemical modifiers including sodium dodecyl sulfate (SDS), calcium carbonate (CaCO[subscript]3), zinc sulfate (ZnSO[subscript]4), calcium chloride (CaCl[subscript]2), and 2-octen-1-ylsuccinic anhydride (OSA) as well as combined chemical modifications. The wet, dry, and soak shear strengths of the adhesive formulations were determined. Viscosity testing, differential scanning calorimetry, and TEM and SEM imaging were used to characterize protein properties. Chemical modification with SDS (1%, 3%, and 5%), CaCO[subscript]3 (1%, 3%, and 5%), ZnSO[subscript]4 (1%), and OSA (2%, 3.5%, and 5%) improved the dry and soak shear strengths compared to unmodified canola protein. Canola protein modified with 3.5% OSA had improved wet, dry, and soak shear strengths. Combined chemical modification of canola protein did not show significant improvement on shear strength. Thermal modification of canola protein adhesives showed a trend of increasing shear strength with increasing press temperature. The data suggests that with further research, canola protein has potential to be used as a commercial adhesive or as an additive to formaldehyde-based adhesives to make them more environmentally-friendly.
206

Demonstrating an approach for modeling crop growth and hydrology using SWAT 2009 in Kanopolis Lake Watershed, Kansas

Mollenkamp, Lorinda Larae January 1900 (has links)
Master of Science / Department of Biological and Agricultural Engineering / Kyle R. Douglas-Mankin / Aleksey Y. Sheshukov / According the U.S. Environmental Protection Agency’s (EPA) website, our planet is at risk of global warming due to greenhouse gas emissions. The earth’s average temperature has been reported to have risen by 1.4°F over the last century. This seemingly small increase in average planetary temperature has been linked to devastating floods, severe heat waves, and dangerous and unpredictable shifts in our climate (US EPA, 2013a). In the 2012 report, the Intergovernmental Panel on Climate Change states that bioenergy has the potential to significantly mitigate greenhouse gases as long as this is produced in a sustainable manner (Chum, et al., 2011). In light of these facts, research into the sustainable production of bioenergy sources in the United States is currently underway. To ensure that the correct biofuel crop is selected for a given region and to investigate any secondary effects of changing our nation’s agricultural practices to include biofuels, computer models can be very useful. The Soil Water Assessment Tool (SWAT) is a robust, continuous time step model that was developed by the USDA Agricultural Resource Service that can simulate changes in land use and land management and the effect this has on erosion, water quality, and other important factors. This paper describes the preliminary work to create a model of the Kanopolis Lake Watershed that is part of the Kansas River Basin using SWAT 2009. Data pertaining to weather, topography, land use, management, stream flow, and reservoirs was gathered and incorporated into the SWAT model. This was then simulated to obtain the uncalibrated data. SWAT produced unacceptable statistics for both crop yields and for stream flow using the Nash-Sutcliffe Efficiency equation and using percent bias. This suggests that the model must be calibrated to be of use in understanding both the current and future land use scenarios. Once the model is calibrated and validated, it can be used to simulate different biofuel cropping scenarios.
207

Tracking military maneuver training disturbance with low cost GPS devices

Denker, Phillip Michael January 1900 (has links)
Master of Science / Department of Biological and Agricultural Engineering / Stacy L. Hutchinson / Military training lands are a vital resource for national security and provide crucial habitat for a number of threatened and endangered species. Military land managers must manage the land in accordance with federal environmental policy and regulation, while simultaneously providing the lands needed for training military forces. Off road maneuver training can cause significant environmental damage including removal of vegetation, compaction of soils, increased erosion, loss of habitat, and degradation of the landscape to a point of not being useful for continued military training. Various techniques have been developed to help the military land managers determine a sustainable training level for the landscape. Many of these techniques have limitations in the spatial resolution of data collected and the ability to provide timely and accurate assessments of training disturbance. Advancements in GPS and GIS technology over the past two decades have shown the potential to fill this knowledge gap. In this study low cost civilian off the shelf (COTS) GPS devices were accuracy tested to determine their capability to provide reliable and accurate military vehicle locations during training (1.93 m CEP, 4.625m 2dRMS). The GPS data collected from COTS devices on three battalion training exercises at Fort Riley, KS were processed in a GIS and statistically analyzed to compare and contrast several off road maneuver metrics (speed, turning radius, distance traveled) by vehicle type tracked, and by platoon in order to determine if units or vehicle types could reliably explain the variation in these metrics. Lastly, a method of mapping the relative environmental disturbance was developed and mapped for the same data sets. Wheel sinkage was used as a measure of disturbance, it was calculated at each GPS point based on vehicle type and soil conditions then mapped in using a fishnet grid for Fort Riley, Kansas.
208

Rapid development of mobile apps using App Inventor and AGCO API

Kepley, Spencer January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Naiqian Zhang / Mobile apps are useful tools for many different purposes. In agriculture, apps can be used to check the weather and markets, control irrigation, and monitor machine activity among other uses. This research project is a collaboration between Kansas State University and AGCO and includes the development of two apps, using MIT Application Inventor and Google App Engine. Kansas State University was responsible for developing the apps user interface and functionality while AGCO provide the data needs for the apps through Google App Engine. The first app is called Crop Maturity App and measures Growing Degree Days from a crops planting date. The second app is called Combine Efficiency App and determines the performance of a combine harvesting based on its speed. AGCO provided the server support for these apps from a weather service and their own combines that are connected. This project demonstrates the possibility of an open-source development environment with AGCO machine data.
209

Sorption of veterinary antibiotics to woodchips

Ajmani, Manu January 1900 (has links)
Master of Science / Department of Civil Engineering / Alok Bhandari / In the upper Midwest, subsurface tile drainage water is a major contributor of nitrate (NO[subscript]3–N) coming from fertilizers and animal manure. Movement of NO[subscript]3-N through tile drainage into streams is a major concern as it can cause eutrophication and hypoxia conditions, as in the Gulf of Mexico. Denitrifying bioreactors is one of the pollution control strategies to treat contaminated tile drainage water. These bioreactors require four conditions which are: 1) organic carbon source, 2) anaerobic conditions, 3) denitrifying bacteria and 4) influent NO[subscript]3-N. This research focuses on investigating fate of veterinary antibiotics in woodchips commonly used in in-situ reactors. Tylosin (TYL) and sulfamethazine (SMZ) are two veterinary antibiotics which are most commonly used in the United States and can be found in tile water after manure is land applied. Partition coefficients of TYL and SMZ on wood were determined by sorption experiments using fresh woodchips and woodchips from an in situ reactor. It was concluded that the woodchips were an effective means to sorb the veterinary antibiotics leached into the tile water after application of animal manure. Linear partition coefficients were calculated and phase distribution relationships were established for both the chemicals. The fresh woodchips gave inconclusive data but predictions could be made by the information determined in the experiments using woodchips from a ten year old woodchip bioreactor. Desorption was also studied and the likelihood of desorption was predicted using the Apparent Hysteresis Index. Overall, it was found that the old woodchips allowed for quick sorption of both antibiotics. It was also found that SMZ had reversible sorption on old woodchips. Thus, it was concluded that the woodchip bioreactor would not be effective for removal of veterinary antibiotics from tile drainage. More research is required for the fate of TYL and to confirm the conclusion.
210

Calibration and testing of a wireless suspended sediment sensor

Bigham, Daniel January 1900 (has links)
Master of Science / Department of Biological and Agricultural Engineering / Naiqian Zhang / A real time wireless, optical sensor network was tested for long-term, remote monitoring of suspended sediment concentrations (SSC) in streams. The sensor and control board assembly was calibrated using a two-stage calibration procedure, including a pre-calibration conducted in the laboratory to adjust the sensitivity of the sensor and a field calibration using grab samples to establish an effective statistical model to predict SSC from the sensor signals. The assembly was installed in three military bases around the United States. These bases were Fort Riley, Kansas; Fort Benning, GA; and Aberdeen Proving Ground, MD. The types of water bodies and watersheds varied greatly among the sites, which allowed the sensor to be tested under versatile conditions for potential widespread use. The results show that the sensor was capable of measuring SSC at each watershed independently. The calibration model developed for each sensor can be used to predict SSC from real-time sensor data. A data processing algorithm was developed to lessen the effect of fouling and clogging on sensor signals, along with eliminating anomalies in the data gathered. The results of this study displayed meaningful prediction data that can be used to estimate SSC in a stream over a long period of time. Information obtained in this study can be used as a launching point for future work and understanding of stream processes.

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