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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.
1

Methods to integrate overland, ephemeral gully and streambank erosion models

Modala, Naga Raghuveer January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Kyle R. Douglas-Mankin / Sediment is considered as one of the important pollutant of concern in the U.S. In order to develop watershed management plans that address sediment pollution, it is essential to identify all sources of sediment in a watershed. The overall goal of this research is to quantify the total sediment from a watershed by integrating the outputs of three types of sediment sources: sheet and rill erosion, ephemeral gully erosion, and streambank erosion, that each operates at different spatial and temporal scales. This approach will be demonstrated in Black Vermillion River Watershed using AnnAGNPS (overland flow/erosion model), REGEM (ephemeral gully erosion model) and field measured values of streambank erosion. The study area includes three subwatersheds (Irish Creek, the Black Vermillion River Main Stem, and North Fork of the Black Vermillion), each monitored for continuous stream flow, base flow and event-based suspended sediment subwatershed export, annual streambank erosion, for 2 years. NASS land use, SSURGO soils data, 30-m DEMs, and local weather data were used to generate input data needed by the models. Stream monitoring data were used to calibrate the models. This paper will present results from independently calibrated and validated combinations of AnnAGNPS, REGEM, and filed measured streambank erosion. Our hypothesis is that use of separate models to simulate sediment load contributions for each sediment source will improve model agreement with measured watershed sediment yield data.
2

Impacts of biota on bioretention cell function during establishment in the Midwest

Greene, Alicia Mathews January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Stacy L. Hutchinson / To understand the region-specific effects of biota on function of bioretention cells, a lysimeter study was conducted at Kansas State University to determine how earthworms and native Kansas grasses impact runoff treatment and hydraulic function of a bioretention cell. This study also employed the Comprehensive Bioretention Cell (BRC) model to demonstrate how three seasons of growth could impact bioretention cell function. The model results of the first season of growth were then compared to field data. Results indicate that the interaction of plant roots and soil macrofauna over one growing season improved several aspects of bioretention cell function. The greatest increase in saturated hydraulic conductivity was in the treatment that included both plants and macrofauna. The presence of vegetation reduced ponding effects and increased water storage. Earthworm treatments had a lesser ability to store water. All treatments were effective in reducing the concentration of P in effluent. A large amount of N was released during all events from all treatments probably because of a high initial N content of the bioretention media. No treatment performed significantly better in improving water quality, indicating that macropore flow in the earthworm treatments did not induce a higher rate of pollutant transport.
3

Assessment of NEXRAD P3 data on streamflow simulation using SWAT for North Fork Ninnescah watershed, Kansas

Gali, Rohith Kumar January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Kyle R. Douglas-Mankin / Radar-derived P3 data from Next Generation Radar (NEXRAD) of the National Weather Service (NWS) offer higher spatial resolution than precipitation gauge data, which might improve the accuracy of streamflow simulations using watershed models. The objective of this study was to evaluate the performance of spatially-averaged subwatershed-specific NEXRAD P3 data on streamflow simulations using Soil and Water Assessment Tool (SWAT) model. The SWAT hydrologic model was chosen for this study to simulate the hydrologic processes in North Fork Ninnescah Watershed located in south-central Kansas. A precipitation gauge station for each subwatershed was created using an area-weighted average of NEXRAD P3 precipitation estimates for all HRAP grid cells covering the subwatershed. The SWAT model was calibrated with both NEXRAD P3 data and NCDC precipitation gauge (PG) data from 1 January 2002 to 31 December 2008. The P3-calibrated model was validated using PG data for the same simulation period (2002-2008), and vice versa. The PG-calibrated model yielded slightly higher daily Nash-Sutcliffe efficiency (E(subscript)NS = 0.40) than P3 calibrated model (ENS = 0.35), but the yearly ENS and PBIAS for P3 calibrated model (ENS = 0.80) was much better than PG-calibrated model (ENS = 0.43). The P3-validated model (PG calibration) had yearly ENS = of 0.70, whereas the PGcalibrated model had ENS = 0.43. The daily PBIAS value for P3-calibrated model in 2007 (wet year) was -14.13 and for the P3-calibrated model was -32.83; PG data overestimated the streamflow compared to P3 data in 2007. The P3 data has better agreement with PG data from 2002-2008 period than for 1996-2001 period. The streamflow estimation was better with NEXRAD P3 precipitation data in both calibration and validation runs. Even though the model was calibrated with PG data, the validated model with P3 data has comparatively high ENS. The spatial variation of streamflow response within the watershed was greater compared to the temporal variation in both the calibrated models. The spatial representation of precipitation data by NEXRAD P3 has improved the modeling performance compared to PG data; it is evident that NEXRAD data is an alternative to precipitation gauge measurements.
4

International education in natural resource engineering and the KSU / EI Purpan AREM partnership

Sloan, Hale C. January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Stacy L. Hutchinson / The need for globally mobile and culturally intelligent engineers to address global natural resource issues is high. Current economic, political and environmental states demand that educational institutions equip engineers with diverse problem solving skill sets. International education experience is the best way for students from varied backgrounds to appreciate differences around the world, develop skill sets for global issues and operate in a multinational environment. International education programs exist between many different educational institutions. A multidisciplinary program, Agricultural Resources and Environmental Management (AREM), currently exists between Kansas State University Manhattan, Kansas, USA and Ecole d’Ingénieurs Purpan Toulouse, France. AREM is a Master’s level program designed to promote the exchange of ideas, faculty, and students in sustainable agricultural development. This program operates independently at each institution and features two courses, revolving around agro-ecological, economic, and social factors, which are co-taught via live video conference. The main objectives of this research were to compare the structural education components of engineering institutes EI Purpan and KSU in order to evaluate the efficacy and importance of the AREM program in global terms, to create a mutual understanding of program obstacles, to highlight the benefits and strengths of each institution, and to provide a common plane for forward progress. Comparisons of accreditation programs, pedagogy and curriculums at the Bachelor’s and Master’s level were conducted. The similarities and differences of the AREM program from both French and American perspectives were explored to develop recommendations for forward progress. Learning outcomes set by accreditation bodies were very similar, but the method of achieving those outcomes was dissimilar. Many differences were found in the amount of time spent on certain educational topics within the engineering curriculum. Engineering students at EI Purpan received a more rounded education, with an agricultural business management focus, enhanced with practical education through required internships. KSU engineering students received a much more technical and theoretical education based in math, physics and engineering design. Pedagogy contrasted most between schedule and on job training. Differences in Master’s degree specialization were limited, but influential. The AREM program is a specialized degree pathway at EI Purpan, while at KSU it is a graduate certificate program. At EI Purpan the AREM program is heavily advertised, while at KSU it is not. Departmental structure of American universities provides challenges to multidisciplinary programs like AREM. The strengths of each institution, practical or theoretical, should be integrated to enhance the AREM program outcomes. Possibilities exist for the AREM program to maintain its current state with minor enhancements, develop into a short summer exchange program between KSU and EI Purpan, or evolve into a joint Master’s degree. The AREM program exposes students to international collaboration, appreciation of different approaches to problems solving, and cultural eccentricities. Engineering students who participate in the AREM program are equipped to solve natural resource issues at the global scale. Improvements to the program will increase student ability and institutional reputability.
5

Determining pen surface water in a cattle feedlot with thermal infrared remote sensing

Leiker, Curtis Joseph January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Ronaldo G. Maghirang / Particulate matter (PM) emissions from open beef cattle feedlots depend heavily on the level of water on the pen surface. Wet pen surfaces are able to keep PM emissions low, while dry surfaces have much higher rates of emission. Current research shows that 20-25% surface water content is a critical threshold for minimizing PM emissions from open cattle feedlots. The amount of water on the pen surface will also dictate the level of gaseous emissions, such as ammonia, nitrous oxide, and hydrogen sulfide. Traditional methods of measuring pen surface water are not sufficient within a dense cattle feedlot and cannot provide a continuous method of measurement unattended. The process of using infrared thermometry and meteorological variables to remotely sense surface water provides an inexpensive, ground level approach. Testing in laboratory, outdoor, and feedlot conditions was conducted to analyze the potential of using the thermal inertia remote sensing approach. This approach involved continuous measurement of weighted soil water content, surface temperature of the soil, air temperature, solar radiation, wind speed, and relative humidity. Controlled laboratory testing performed the best at predicting soil water content from the difference in soil surface and air temperature, with the coefficient of determination (R2) at 0.91 for a Smolan silt loam and 0.83 for dry feedlot soil. Outdoor testing achieved mixed results with R2 values only as high as 0.38 for 10-cm soil layer and 0.67 for 5-cm soil layer. Testing in a cattle feedlot with dry, loose manure layer proved to be imprecise, but was able to differentiate surface water levels varying from 4.1% to 9.1% wet basis.
6

Evaluation of vegetated filter strips for attenuation of pollutants resulting from military activities

Satchithanantham, Sanjayan January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Stacy L. Hutchinson / A field study was conducted at Fort Riley, Kansas from late spring to early winter of 2007 to investigate the ability of vegetated filter strips (VFS) to attenuate pollutants resulting from military activities, the impact of different management practices (i.e. burning and mowing) on VFS performance, and the effects of vegetation on hydrological components of VFS, especially infiltration and runoff. Two native tallgrass VFS sites, each comprising three plots, located in the military training area of Fort Riley were used for this study. Fifteen rainfall events were simulated on each site along with overland application of water containing nitrogen (N), phosphorous (P) and sediment. At the end of the season both VFS were managed by mowing or burning and a final rainfall simulation was done. Variables including rainfall, infiltration, runon, runoff, above ground biomass density, pollutant concentrations of runon and runoff, and soil moisture were measured and used in the data analysis. Hydrograph development, water balance, and mass balance calculations were carried out in order to calculate the pollutant trapping efficiencies (PTE) of the VFS. Statistical analysis was done by fitting several regression models. Mean comparisons were also done for variables and variance was decomposed into time, plot and site effects at an alpha = 0.05. Results showed that on average the VFS attenuated 84 % of total nitrogen, 24 % of total phosphorous and 95 % of sediments. Regression models showed that infiltration percentage and biomass density have a positive correlation with PTE. Runoff volume and PTE were negatively correlated. Soil moisture was negatively correlated with infiltration and time to runoff. With increasing biomass density, percentage of water infiltrating and time of concentration increased. Management practices, especially burning, tended to reduce PTE. Also, both management practices reduced infiltration percentage and time of concentration. PTE reduced with intensifying rainfall and increased when rainfall faded off. Phosphorous was the most sensitive pollutant for intense storm conditions followed by nitrogen, while sediment was comparatively insensitive.
7

Climate responsive vernacular architecture: Jharkhand, India

Gautam, Avinash January 1900 (has links)
Master of Science / Department of Architecture / R. Todd Gabbard / This research aims to explore and assess passive solar design techniques that promote high thermal comfort in vernacular houses of the state of Jharkhand in India. The study of these houses provides useful insights for designing energy efficient houses that provide thermally comfortable conditions. An analysis of these houses in Ranchi, the capital city of Jharkhand, India provides a context for the field research. Jharkhand predominantly has two different styles of vernacular houses: huts and havelis. These houses were constructed, without any mechanical means, in such a manner as to create micro-climates inside them to provide high thermal comfort levels. Hence the study of thermal comfort levels in these buildings in relation to built environment in today's context is significant. As part of data collection, interviews were conducted with the occupants of ten houses in Ranchi, in June 2007. Two houses of each (huts and havelis) were selected for detailed experimental analysis. Experiment results indicated that all the four selected houses exhibited lower ambient temperature than outside during the day and a higher ambient temperature at night. Brick bat coba and lime mortar were the key materials used for constructing high thermal-mass walls. Adequate ventilation is significant in creating conditions that are comfortable. Aperture to volume ratio of less than 0.051 is not adequate enough to cool the thermal mass of these houses. These houses also use attic space to mitigate the heat gain from the roof. Courtyards and other exterior spaces form an integral part of these houses and influence the thermal conditions in and around the houses. The case studies show that there is a scope for more relaxation of comfort temperature range based on culture and phenomenon of acclimatization. A universal approach in understanding and defining comfort condition fails because the users of these houses were comfortable in conditions defined as uncomfortable by ASHRAE and Nicol.
8

Greenhouse gas emissions and strategies for mitigation: opportunities in agriculture and energy sector

Parihar, Arun K. January 1900 (has links)
Master of Science / Department of Chemical Engineering / Larry E. Erickson / The impact of human activities on the atmosphere and the accompanying risks of long-term global climate change are by now familiar topics to many people. Although most of the increase in greenhouse gas (GHG) concentrations is due to carbon dioxide (CO2) emissions from fossil fuels, globally about one-third of the total human-induced warming effect due to GHGs comes from agriculture and land-use. This report provides a brief review of greenhouse effects and impacts on climate, human health and environment. The sources of emissions of greenhouse gases due to human activities, both current estimates and future projections, have been included. The report further discusses possible options for mitigation of greenhouse gases. The report also discusses the role agriculture can play towards mitigation of greenhouse gases as many agricultural processes such as anaerobic digestion, manure gasification; carbon sequestration etc. can help reduce or offset greenhouse gas emissions. Capture and sequestration of CO2 released as a result of burning fossil fuel in power plants, energy and other industries is gaining widespread interest as a potential method of controlling greenhouse gas emissions. Various technologies such as amine (MEA)-based CO2 absorption system for post-combustion flue gas applications have been developed, and can be integrated with existing plant operations. Removal of SO2 by using amine-based carbon capture system offers additional benefit. Efforts are underway to develop a broader suite of carbon capture and sequestration technologies for more comprehensive assessments in the context of multi-pollutant environmental management. Geologic formations and/ or possibly oceans can be used as sinks to store recovered CO2. In oil and gas exploration industry CO2 may be injected in producing or abandoned reservoirs which will not only help in maintaining the reservoir pressure (which improves overall field exploitation) but in some cases even leads to enhanced oil recovery.
9

Experimental investigation of optimal particulate sensor location in an aircraft cabin

Shehadi, Maher F. January 1900 (has links)
Master of Science / Department of Mechanical and Nuclear Engineering / Mohammad H. Hosni / Each year millions of people travel by commercial aircrafts. The Bureau of Transportation Statistics indicates that about 600 million passengers fly each year in the United States and, of those, roughly 350,000 are international travelers. This number of travelers leaves commercial airliners potentially vulnerable to biological contamination and makes the transmission of diseases a serious threat. The spread of SARS (Severe Acute Respiratory Syndrome) and H1N1 (swine flu) are examples of documented cases. Consequently, considerable research has been and continues to be conducted to study and understand particulate transport mechanisms and dispersion behavior inside aircraft cabins to develop means for detecting, controlling, and removing contaminants from aircraft cabins and to find methods for preventing the aircraft from being used for intentional contaminant deployment. In order to develop means to monitor and control air quality, infectious disease transmission, and particulate transport inside aircraft cabins, an experimental study was conducted to determine the best sensor placement locations for detection and to identify the number of sensors needed to accurately track air quality incidents within a cabin. An 11-row mockup, intended to be representative of a typical wide-body aircraft, was used for the research. The mockup interior is based on the actual dimensions of the Boeing 767 aircraft cabin. Inside the mockup cabin, actual aircraft equipment including seats and air diffusers were used. Each row has seven passenger seats. Particulates were released from different locations in the second row of the mockup cabin. The transported particles were then collected at six different locations in the lateral direction. The best location to place a sensor was defined as the location having the strongest signal (maximum number of particles collected) or the fastest detection time. After determining the best location in the lateral direction, particles were collected at the same location, but in different rows to estimate the differences between the signal strength and the delay time in detecting the signal from row to row. For the later investigation, the particulates were released in Row 2 and in Row 6 as well. For the six locations examined, it was found that the best location for the placement of a sensor in the 11-row mockup in the lateral direction is on the centerline near the cabin floor. Longitudinally, it was found that a sensor may be used for detecting particulates in the same row as the release and a row in front and in back of the release location. For the mockup cabin, a total of 4 sensors was recommended to monitor particulate releases in the 11 row mockup cabin, each of these sensors separated by two rows.
10

Antibiotic resistance patterns in municipal wastewater bacteria

Nagulapally, Sujatha Reddy January 1900 (has links)
Master of Science / Department of Civil Engineering / Alok Bhandari / Antibiotics and pharmaceuticals are used to improve the quality of life worldwide. However, incomplete metabolism in humans has resulted in the release of large amounts of pharmaceutical drugs into municipal wastewater treatment plant. Past research has shown the release of antibiotic resistant organisms through wastewater effluents into streams and several studies have reported the occurrence of antibiotic resistant bacteria in major U.S. Rivers. Antibiotic resistant bacteria evolve and are selected by long-term environmental exposure to the low concentrations of antibiotics at the ng /L to g/L range. Infections caused by antibiotic resistant organisms are difficult to treat. The aim of this study was to analyze antibiotic resistance patterns in selected wastewater bacteria that include fecal coliforms, Escherichia coli and enterococci. Microorganisms in municipal wastewater treatment plant influent, secondary clarifier effluent and disinfected effluent were plated in the presence of predetermined concentrations of selected antibiotics. These antibiotics included ciprofloxacin, sulfamethoxazole/ trimethoprim and vancomycin. The diversity of enterococci was further investigated with PCR analysis. Fecal coliforms, E. coli and enterococci were found to be resistant or highly resistant to one or more target antibiotics in the influent and secondary clarifier (SC) effluent. Biological treatment reduced the number of overall and resistant bacteria in the SC effluent sample. UV disinfection was generally very effective and eliminated all fecal indicator organisms.

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