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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.
341

Evaluation of the 5-day vs. 7-day Co-Synch + CIDR protocol in dairy heifers using timed AI.

Mellieon, Harold Irvin Jr. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Jeffrey S. Stevenson / Our objectives were to determine: the effectiveness of upfront PGF2α injection to regress the corpus luteum; ovulation response to GnRH; and pregnancy outcomes. Dairy heifers (n = 545) from three locations (Florida, Kansas, and Mississippi) were assigned randomly to each of two treatments: 1) 25 mg of PGF2α injection and insertion of previously used autoclaved CIDR on d 7 followed by 100 µg of GnRH administered on d 5, and a 25 mg PGF2α injection at CIDR removal (7D) on d 0; 2) 100 µg of GnRH and insertion of previously used autoclaved CIDR on d 5 and 25 mg of PGF2α injection at CIDR removal (5D) on d 0. Artificial insemination (AI) occurred after detected estrus from d 0 to 3. Those heifers not detected in estrus were inseminated on d 3 and given a second 100 µg of GnRH. Blood collected on d 7 and 5 was assayed to determine concentrations of progesterone, presence of a CL (progesterone ≥1 ng/mL) on d 7, and whether luteolysis occurred in 7D heifers. Blood progesterone concentration from d 0 and 3 determined if luteolysis occurred in all heifers. Ovarian structure maps on d 5 and 0 were used to determine ovulation in response to GnRH on d 5. Pregnancy was determined on d 32 and 60 and intervening pregnancy loss was calculated. Of those heifers in the 7D treatment having progesterone ≥1 ng/mL on d 7, the proportion having progesterone <1 ng/mL 2 d later (luteolysis) was greater (P < 0.05) than that in the 5D treatment (43.0 vs. 22.9%, respectively). Total proportion of follicles that ovulated per heifer was numerically greater in the 7D treatment but only differed (P < 0.05) between locations. A treatment x location interaction was detected for pregnancy rates per AI. The Kansas location had no detectable treatment differences. In contrast, the 7D treatment produced greater (P < 0.05) pregnancy rates in the first replicate of the Florida location and at the Mississippi location. We concluded that the 5D protocol was not effective in producing acceptable luteolysis, pregnancy, and ovulation rates in comparison with the modified 7D protocol.
342

A cost analysis for the densification and transportation of cellulosic biomass for ethanol production.

Wilson, Jonathan January 1900 (has links)
Master of Science / Department of Grain Science and Industry / Leland McKinney / The current forage handling equipment in the cellulosic ethanol industry is severely limited by the low bulk densities of baled and ground biomass. Low bulk densities contribute to flowability problems and lack of maximizing trailer capacities. By pelleting we can increase the bulk density and flowability characteristics of forages. The objectives of this research were to evaluate (1) the energy requirements of grinding sorghum stalks, corn stover, wheat straw and big bluestem through two different screen sizes, (2) the energy requirements of pelleting forages from the two grind sizes, and (3) the physical properties of our various end products. The two screen types were found to have significantly different energy consumptions from each other (P<.0001). The majority of the four forage types were also found to have significantly different energy consumptions for grinding from each other (P<.0001). The exception was big bluestem vs. corn (P=.2329). All of the 1/8” vs. 1/8” and 1/8” vs. 3/8” grinds were significantly different from each other (Most P<.0001 and all at least P<.05). 3/8” sorghum was significant against all other 3/8” forage types. No other comparisons were significant for 3/8” vs. 3/8” (All 3/8” sorghum P<.0001). Production rate through the 3/8” screen was almost 3 times that of the 1/8” screen (Average of 400 lb/hr vs. 150 lb/hr). The two screen types were found to have significantly different energy consumptions for pelleting from each other (P<.0001). The four forage types were also found to have significantly different energy consumptions from each other (P<.0001) while the big blue vs. wheat did not. (P=.1192). Particle length for the 1/8” grind ranged from .06 inches to .07 inches, while the 3/8” grind ranged from .08 inches to .12 inches. Pelleting increased bulk density from 6.24 lb/ft3 to 9.99 lb/ft3 for biomass grinds to 31.17 lb/ft3 to 43.77 lb/ft3 for pelleted biomass. Pellet quality ranged from 93% to 98%. A cost analysis indicated that it would take roughly $20 extra per ton for the transportation, pre-processing and storage of pelleted cellulosic biomass than whole corn. This cost is still almost half that of the cost for baled biomass.
343

A real-time control system for a frequency response-based permittivity sensor

Tang, Ning January 1900 (has links)
Master of Science / Department of Biological & Agricultural Engineering / Naiqian Zhang / Permittivity is an important property of dielectric materials. By measuring the permittivity of a material, it is possible to obtain information about the material’s physical and chemical properties, which are of great importance to many applications. In this study, a realtime control system for a frequency-response (FR) permittivity sensor was developed. The core of the hardware was a kitCON167 microcontroller (PHYTEC America, LLC), which controlled and communicated with peripheral devices. The system consisted of circuits for waveform generation, signal conditioning, signal processing, data acquisition, data display, data storage, and temperature measurement. A C program was developed in the TASKING Embedded Development Environment (EDE) to control the system. The control system designed in this study embodied improvements over a previously designed version in the following aspects: 1) it used a printed circuit board (PCB); 2) the measurement frequency range was extended from 120 MHz to 400 MHz; 3) the resolution of measured FR data was improved by using programmable gain amplifiers; 4) a data storage module and a real-time temperature measurement module were added to the system; 5) an LCD display and a keypad were added to the system to display the FR data with corresponding frequencies and to allow users to enter commands. Impedance transformation models for the sensor probe, the coaxial cable that connects the control system with the sensor probe, and the signal processing circuit were studied in order to acquire information on the permittivity of measured materials from measured FR data. Coaxial cables of the same length terminated with different loads, including an open circuit, a short circuit, a 50 resistor, and a 50 resistor paralleled by a capacitor, were tested. The results indicated that the models were capable of predicting the impedances of these specific loads using the FR data. Sensor probes with different sizes and coaxial cables with two different lengths terminated with the same sensor probe were also tested. The results were discussed. Additional tests for the gain and phase detector were conducted to compare FR data measured by the gain and phase detector with those observed on an oscilloscope. The results were discussed.
344

Determining and meeting the educational needs of students and urban gardeners and farmers on urban soil quality and contamination topics

Harms, Ashley Marie Raes January 1900 (has links)
Master of Science / Department of Agronomy / DeAnn Presley / Steve Thien / Interest and participation in urban agriculture is growing in many cities throughout the United States. Urban gardeners and farmers produce food on various types of urban lands. Common soil contaminants of urban areas limit the amount of land on which food may safely be grown. The objective of this study was to assess and meet the informational and technical assistance needs of urban gardeners and farmers as well as students enrolled in the introductory soils science course at Kansas State University on the topics of urban soil quality and contamination. A needs assessment survey of urban gardeners and farmers was conducted in four communities; Tacoma and Seattle, Washington, Kansas City, Kansas and Missouri, Manhattan, Kansas, and Gary, Indiana. The survey generated information about what urban gardeners and farmers know, think they know, and want to know about urban soil quality and contamination. Eighty-eight percent of respondents indicated that they do not have knowledge of the best management practices to minimize health risks involved when growing food crops on soils contaminated with lead, cadmium, arsenic or organic contaminants. Our results suggest that urban gardeners and farmers require and want information and guidance on soil testing for common contaminants, interpretation of testing results, and best management practices for growing food on mildly contaminated soils. The students enrolled in the introductory soil science course at Kansas State University are future agricultural and environmental professionals who need skills to address urban soils issues. Most of the students in the Agronomy 305: Soils course are not Agronomy majors. Furthermore, an increasing number of Agronomy 305 students come from urban and suburban communities and/or have interest in working in urban environments upon completion of their undergraduate degree. An urban soils laboratory was developed in response to the future workforce demands as well as the demographics of students enrolled in the Agronomy 305 course. Throughout the semester students evaluated the physical, chemical, and biological properties of a soil from this urban community garden. Reaction of students to the new urban soils lab offering has been positive with 72% of students enrolled in the course reporting that they have interest and need in learning about the urban soil issues covered in the lab course. Overall, student responses about their learning experience in the urban soils laboratory course were positive, indicating that incorporating urban soil principles enhanced their soil science education. Students who participated in the urban soils lab are better prepared, as future agricultural and environmental professionals, to address the educational and technical assistance needs of urban growers.
345

Continuous infusion of TNF alpha in adipose tissue does not induce the same metabolic effects as daily bolus injection in lactating dairy cows

Martel, Cynthia Ann January 1900 (has links)
Master of Science / Department of Human Nutrition / Tonatiuh Melgarejo / Late-lactation Holstein cows (n=9/treatment) were used to evaluate effects of continuous adipose tissue TNFα administration on glucose and fatty acid (FA) metabolism. Cows were blocked by feed intake and milk yield and randomly assigned within block to control or TNFα treatments. Treatments (4 mL saline or 14 μg/kg TNFα in 4 mL saline) were infused continuously over 7 d via 2 osmotic pumps in the adipose layer in the tailhead region. Plasma, milk samples, milk yield, and dry matter intake (DMI) data were collected daily. On d 7, pumps were removed and liver and contralateral tailhead adipose biopsies were collected. Results were modeled with fixed effect of treatment and random effect of block; P values > 0.10 were considered non-significant. TNFα did not alter liver TNFα mRNA abundance, plasma TNFα, IL-4, IL-6, or interferon-γ concentrations, DMI, or rectal temperature. Milk fat and lactose concentrations decreased with TNFα (P < 0.05), but milk yield was unchanged and treatments did not alter the proportion of short vs. long-chain FA in milk on d 7. Treatments did not alter plasma NEFA concentration, liver triglyceride content, or adipose mRNA abundance for hormone-sensitive lipase or perilipin. Plasma glucose turnover rate, as measured by disappearance of U-13C-glucose bolus, was not altered by treatment, nor was liver mRNA abundance for phosphoenolpyruvate carboxykinase or pyruvate carboxylase. However, TNFα tended to decrease adipose TNFα mRNA abundance (P=0.09) and increase liver IL-10 mRNA abundance (P=0.05) compared to controls. Messenger RNA expression of IL-10 in adipose and IL-37 in liver tissue increased significantly in cows treated with TNFα (Figure 1; P = .02 adipose; P < 0.05 liver). This TNFα delivery protocol may have allowed for an adaptive anti-inflammatory response to suppress systemic inflammation, which may account for the lack of metabolic responses compared with previous responses to daily subcutaneous TNFα injections.
346

GIS methods to implement sediment best management practices and locate ephemeral gullies

Daggupati, Naga Prasad January 1900 (has links)
Doctor of Philosophy / Department of Biological & Agricultural Engineering / Kyle Douglas-Mankin / Soil erosion is one of the most important of today’s global environmental problems. Over the past few decades, soil conservation practices were implemented to reduce soil erosion in the United States. However, excessive sediment still remains among the most prevalent water quality problems. Agricultural fields and in particular ephemeral gullies (EGs) are considered to be a major contributor of sediment. The overall goal of this study was to improve modeling utility to identify and quantify sources of sediment. Specific objectives were: (1) to develop and demonstrate a method of field-scale targeting using Soil and Water Assessment Tool (SWAT) and to use this method as a targeted, flexible approach to pay explicitly for sediment-yield reductions; (2) to evaluate topographic index models (Slope Area [SA], Compound Topographic Index [CTI], Slope Area Power [SAP] and Wetness Topographic Index [WTI]) and a physical-based model (Overland Flow Turbulent [OFT]) in predicting spatial EG location and lengths. Black Kettle Creek watershed was the focus of an innovative project to pay for modeled field sediment reductions. An Arc-Geographical Information System (GIS) tool bar was developed that post processed SWAT hydrologic response unit output to field boundaries and prepared maps of high-priority fields by sediment, total nitrogen, and total phosphorus and was demonstrated to be useful for field-scale targeting. Calibrated SWAT model was used to establish baseline sediment yields. Various Best Management Practices (BMPs) were simulated and payments to implement each BMP for a given field were calculated. This study helped to guide determination of appropriate farmer support payments and quantified the important influence of BMP type and site-specific conditions for use in targeting conservation practice funding to achieve maximum soil-loss reductions per dollar spent. Extreme care should be used in selecting the source of spatial model input data when using SWAT for field-level targeting. Automated geospatial models were developed in a GIS environment to spatially locate and derive length of EGs using topographic index and physical based models. EG predictions were better for the SA model among the four topographic index models tested. Individual calibration of topographic index model threshold for each application site was needed. An OFT model (physical based model), which utilized topography, precipitation, soil, landuse/landcover and SWAT-based runoff estimates, did not need individual site calibration, and may have broader applicability than empirical based models.
347

Evaluating factors affecting pellet durability and energy consumption in a pilot feed mill and comparing methods for evaluating pellet durability

Fahrenholz, Adam Charles January 1900 (has links)
Doctor of Philosophy / Department of Grain Science and Industry / Keith C. Behnke / A series of experiments was conducted to compare methods used to evaluate the durability of animal feed pellets, as well as to investigate the potential for modeling the effects of formulation and processing factors on both pellet durability index (PDI) and pelleting energy consumption, measured in kilowatt hours per ton (kWh/ton). Seven different factors, including ground corn particle size, added fat level, inclusion of distillers dried grains with solubles (DDGS), feed rate, steam conditioning temperature, conditioner retention time, and pellet die thickness (L:D ratio) were examined. Each factor was evaluated at two levels, and treatments were developed in order that all factor to factor comparisons could be made. Pellet samples were analyzed according to the standard method as described in ASAE S269.4, a modification of this method, and by using the NHP100 pellet tester set to each of its four testing intervals (30, 60, 90, and 120 seconds). The standard method was found to provide the most consistent and repeatable determinations of pellet durability, and was found to correlate well with the modified method, as well as with the NHP100 results at 30 and 60 seconds. Physical attributes of feed pellets, such as pellet hardness, bulk density, and moisture content were found to have significant, but weak correlations with pellet quality. Pellet quality was found to be significantly influenced by all factors other than ground corn particle size and feed rate. Higher fat level, lower conditioning temperature, and the thinner pellet die most significantly lowered pellet quality, with increasing effect respectively. A regression model was developed that was able to predict pellet durability within an average of 1.1 PDI. Pelleting energy consumption was found to be significantly influenced by all seven factors, with the higher fat level, thinner pellet die, and higher conditioning temperature most improving efficiency, with increasing effect respectively. A regression model was developed that was able to predict energy consumption within an average of 0.3 kWh/ton. The successful creation of regression equations demonstrates that there is potential for modeling and optimizing pellet quality and energy consumption within a pelleting operation.
348

Inbound wheat railcar loading optimization: an opportunity cost study for ConAgra Mills

Jordan, Erin January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Christine Wilson / The objective of this thesis is to examine the opportunity cost, both financial and efficiency, of inbound railcars of wheat that are not optimally loaded and shipped to ConAgra Mills’ facilities. In performing an analysis of data showing actual versus optimal weights, a cost will be assigned to determine how much “dead freight” or extra freight is being paid to railroads for space not utilized. Throughout the analysis, it can be determined which shippers are lacking efficiencies in loading as well as those who are meeting ConAgra Mills’ expectations. To accomplish this objective, data were extracted from various sources for an entire fiscal year and 22,351 data observations were analyzed. The information was specific to both individual railcars as well as the shipments as a whole. These data points were analyzed in two ways, financial and capacity/efficiency. Financially, a cost was assigned to each railcar that was under the railcar’s goal weight. From a capacity perspective, railcars were analyzed on a shipment basis to indicate if equipment could be saved by more efficient loading. The study determined that savings could be found in every situation analyzed. It was determined that in addition to inbound shipments from outside shippers, inter-mill shipments between ConAgra Mills facilities were affected by loading inefficiencies. There could be an opportunity for further analysis to determine the full scope of savings beyond the limitations of this study. The main limitation of this thesis was the primary source of data.
349

Precision agriculture adoption by growers in South Central Nebraska

Fickenscher, Tyrell January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Kevin Dhuyvetter / This thesis was commissioned by Cooperative Producers, Inc. (CPI) of Hastings, Nebraska in order to better understand the preferences and uses of precision agriculture by customers within the company’s trade territory. With the rapid increase of precision agriculture (hardware, software, services, etc.) it is necessary to get a better understanding of what drives growers to adopt and implement precision agriculture practices. A paper survey was sent out in CPI’s monthly statements to patrons that also included instructions to be able to fill out an online survey if that was preferred. From that offering there were a total of 114 responses providing data from which several technology adoption models were estimated. Based on prior experience with precision agriculture and the development of services offered to growers, it is hypothesized that there are three primary variables influencing a grower’s decision to adopt precision agriculture. If the operation is managed by a younger grower (<40 years old), farms with a larger number of acres, and if a high percent of the operation’s acres are irrigated they will be more likely to adopt precision agriculture practices. The survey results generally revealed that younger farmers, larger farm size, and a higher percentage of irrigated acres did not increase the likelihood of utilizing precision agriculture. The questions asked in the survey were designed to provide information for the development of a tool that salespeople offering precision agriculture services could use to determine if a potential customer with be inclined to adopt and utilize precision agriculture. While some of the results were contrary to expectations they do offer insight into what type of customer adopts precision agriculture and a direction for CPI to move in order to maximize market penetration.
350

The economics of corn cob cellulosic ethanol for northwest Iowa

Schany, William J. January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Michael Woolverton / To meet the demand of the 2007 Energy Bill will require a new approach to ethanol production in the United States. The question persists: how can the ethanol industry in the United States produce 21 billion gallons of ethanol from cellulosic sources? This challenge will require changes in the facilities currently manufacturing ethanol, the collection and storage methods to which the Midwestern farmer is accustomed, and a drastic change in farm production practices. Several different methods of cellulosic ethanol production are being examined. One such method is to change the focus from starch based ethanol to ethanol produced by harvest, collection, and manufacture from corn cobs. Research has included surveys, development of economic models, and focus group meetings to determine the feasibility of corn cobs as a viable raw material source for cellulosic ethanol. Findings indicate that: corn cob collection is feasible for the Midwestern farmer. According to the economic models presented in this thesis, Midwestern farmers can benefit economically from the collection of corn cobs. Further, the collection of corn cobs allows for current ethanol plants to be upgraded with new technology without major change in the manufacturing processes. The focus of this research was to determine which method of corn cob collection was preferable for Midwestern corn producers.

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