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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.
681

Effect of selective dry cow therapy on udder health of US dairy herds

Torres, Audrey H. 26 June 2007 (has links)
No description available.
682

Permeability of Lake Ice in the Taylor Valley, Antarctica: From Permeameter Design to Permeability Upscaling

Carroll, Kelly Patrick 15 April 2008 (has links)
No description available.
683

Evaporation is the Primary Mechanism of Tear Film Thinning

Kimball, Samuel H. 08 September 2009 (has links)
No description available.
684

Comparison of Symptoms, Signs, Composition, and Tear Film Dynamics in Sjögrens vs. Non-Sjögrens Subjects

Paulett, Christopher Lewis 30 July 2010 (has links)
No description available.
685

Dynamics and Variability of Foehn Winds in the McMurdo Dry Valleys Antarctica

Steinhoff, Daniel Frederick 25 July 2011 (has links)
No description available.
686

Solid-state Anaerobic Digestion of Lignocellulosic Biomass for Biogas Production

Liew, Lo Niee 28 July 2011 (has links)
No description available.
687

Laboratory Investigation of Quarry Fines for Use in the Construction Industry

Filippidi, Antonia January 2022 (has links)
Quarry fines are by-products of the aggregate extraction and productionprocesses. Because such fine material cannot be marketed, it becomes aburden for the aggregate industry, resulting in stockpiles of financiallyunexploited material. Even though previous research has been focused onminimizing the generation of quarry fines, far too little attention has beenpaid to maximizing their utilization instead. The aim of this thesis is toinvestigate whether 0/2 mm and 0/4 mm quarry fines can be utilized asalternative materials in the construction industry, specifically in theunbound layer of a road or as filling against a bridge. The methodologyconsisted of four laboratory tests that investigated the water content,particle size distribution and percentage of filler content, optimummoisture content (OMC) and maximum dry density (MDD) relationshipas well as bearing capacity of the materials. The results show that theamount of filler content (<0.063 mm) can significantly impact thematerial’s water-holding capacity as well as its compaction capabilities.After comparing the bearing capacity measurements to the technicalrequirements of the Swedish Transport Administration, it was found thatthe 0/2 mm fits the necessary requirements for use in the unbound layerof either a flexible or rigid pavement but not as filling against a bridge.Further research is needed to determine the material’s relationship towater absorption and resistance to freezing and thawing cycles, as it isdifficult to assess its suitability for road construction solely on theseresults; however, despite its limitations, the study provides some valuableinsights into the potential applications of quarry fines.
688

Growth, leaf gaseous exchange and nutritive value of selected summer forage legumes and their contributions to succeeding winter grass (Secale cereale) in District Agro-ecological zone of Limpopo Province

Lekgothoane, Philemon Lesetja January 2022 (has links)
Thesis (M.Sc. (Pasture Science)) -- University of Limpopo, 2022 / In South Africa, livestock production is a rapidly growing business in the agricultural sector contributing up to 46.9% of the gross domestic value. The shortage of adequate, good quality forage during the winter months is one of the biggest problems confronting livestock farmers in the Limpopo Province. This study was initiated in 2019 to evaluate the production potential and nutritive value of different summer annual forage legumes, namely sunnhemp (Crotalaria juncea), forage cowpea (Vigna unguiculata), lablab bean (Lablab purpureus), and pigeon pea (Cajanus cajans), and their impact on succeeding winter stooling ryegrass (Secale cereale), at the University of Limpopo experimental farm Syferkuil and a Cooperative farmers’ field at Ofcolaco. The study was evaluated in a randomized complete block design with four replications. Dry matter yield, crude protein, crude protein yield, leaf chlorophyll content, Normalized Difference Vegetative Index (NDVI), and leaf gaseous exchange parameters of forage crops were statistically analysed with Statistical Analysis System (SAS), Enterprise Version 9.4, using the least significant difference (LSD) method for mean comparison. Pigeon pea biomass accumulation was 57% lower than the average of the three other legumes at Syferkuil. Sunnhemp produced superior biomass (P<0.05) compared to the other three species, reaching a peak yield of 3142.4 kg.ha-1 and 8970.8 kg ha-1 at Syferkuil and Ofcolaco, respectively. Cowpea and lablab produced similar biomass at Syferkuil. The crude protein content of the forage species ranged from 22.91% to 26.82% at Syferkuil and 17.03% to 23.84% at Ofcolaco. Leaf chlorophyll content differed (P<0.001) among the forage legume species at both locations with cowpea producing the highest chlorophyll content at Syferkuil, whereas at Ofcolaco, pigeon pea constantly produced the highest chlorophyll compared to other species. Pigeon pea was the only species rated moderately healthy with Normalised Difference Vegetative Index (NDVI) readings at Syferkuil, unlike at Ofcolaco where all forage legumes were rated as very healthy. At Syferkuil, no root nodules were observed among all the forage legumes at all sampling dates but at Ofcolaco, nodules were produced at 44 DAE with cowpea producing the highest, 92.32% higher than the average of sunnhemp, lablab, and pigeon-pea. At this location pigeon pea did not nodulate. The transpiration rate at Syferkuil was significant (P<0.01) among the species starting with a low transpiration rate from 24 days after planting and reaching their peak at 66DAE. Overall, pigeon pea had the highest (P<0.05) mean transpiration rate compared to the other species. At Ofcolaco the forage legume treatment did not have any significant (P>0.05) influence on transpiration rate, stomatal conductance and sub-stomatal conductance. The transpiration rate of the species ranged from 0.1 mol m-2 s -1 to 5.15 mol m-2 s -1 across all sampling dates whereas stomatal conductance ranged from 0.06 to 5.59 mol m-2 s -1 at Syferkuil and 0.1 to 5.15 mol m-2 s -1 at Ofcolaco, across all sampling dates and species. At Syferkuil, the mean stomatal conductance values ranged from 129.75 mol m-2 s -1 to 374 mol m-2 s -1 across the sampling dates and species, whereas, at Ofcolaco, the means ranged from 185 mol m-2s -1 to 390.25 mol m-2s -1 . The succeeding stooling rye produced a similar biomass yield under every preceding forage legume. This can be concluded that all the four forage legumes did not have any effect on the biomass production of stooling rye. However, there appeared to be a tendency of higher biomass production in the grass species grown after pigeon pea and lablab compared to those following sunnhemp and cowpea. Further experiments are required to establish the full benefits of the forage legumes on succeeding forage grass crop. Based on the results from this study, it was concluded that sunnhemp can be considered as the first choice forage legume at both Syferkuil and Ofcolaco due to its consistently high biomass production, comparable nutrient profile, high crude protein content and high protein yield compared with the other legumes. Though sunnhemp was superior, the other forage summer legumes species studied also managed to produce enough biomass for grazing and had similar nutritive value which was above minimum recommendations. They can therefore be cultivated in the province to meet the constraint of the feed gap in the province. Additional studies at different locations, however, will help to understand the productivity of the species and also to establish the full benefits of the forage legumes on succeeding forage grass crops / National Research Foundation (NRF) and Department of Science and Innovation
689

Cultivos de cobertura en molisoles de la Región Pampeana : producción de materia seca, eficiencia en el suelo del agua y del nitrógeno e incidencia sobre el cultivo de soja

Scianca, Carlos María 04 October 2010 (has links)
La alta frecuencia de cultivos de oleaginosas con moderados aportes y persistencia de residuos podría limitar la normal productividad de los suelos. La inclusión de cultivos invernales (utilizados como cultivos de cobertura, CC) en la región semiárida y subhúmeda pampeana sería una alternativa para proveer de residuos ricos en C y promover al desarrollo y al mantenimiento de la cobertura de los suelos. Pero se reconoce que el consumo hídrico de éstos podría interferir en la oferta de agua para el cultivo siguiente. El objetivo de este estudio fue evaluar la eficiencia en la producción de materia seca (MS) de cereales de invierno utilizados como CC y sus efectos sobre los contenidos de agua útil y nitratos en suelos diferenciados por el régimen hídrico. Los estudios se desarrolla-ron en 4 sitios experimentales [Luan Toro (LP) (Haplustol Entico, precipitación 624 mm), Dorila (LP) (Haplustol Entico, precipitación 873 mm), General Villegas (BA) (Hapludol Thapto Árgico, precipitación 906 mm) y General Pinto (BA) (Argiudol Típico, precipitación 1116 mm)]. Los tratamientos fueron: Secale cereale (C), Lolium multiflorum (R), Avena sativa (A) y un tratamiento Testigo, sin CC (T). La producción de MS al momento del secado de los CC varió entre 1226 y 10500 kg ha-1. Se observó una gran influencia del régimen hídrico de los suelos sobre la producción del MS de los CC. El contenido de agua total al momento de la siembra explicó el 57 % de la variabilidad de la producción de MS, mientras que el contenido de agua total en el suelo a la siembra más las precipitaciones durante el ciclo de desarrollo de los CC, explicó el 89 % de la variabilidad. En todos los sitios el centeno produjo la mayor cantidad de MS, seguida por la avena y el rye grass. La mayor variación se dio dentro del mismo sitio, entre los años de evaluación. El uso consuntivo hasta el momento del secado varió entre 88 y 299 mm. La especie con mayor eficiencia de uso de agua fue el centeno, alcanzando su máximo valor en el sitio de General Pinto (54 kg MS mm-1). Los valores de resistencia a la penetración fueron mayores bajo los tratamientos con CC y tuvieron una relación significativa con los contenidos hídricos del suelo. Sólo en el sitio Dorila los mayores valores fueron registrados en el tratamiento T, sin comprobarse relación significativa entre variaciones en la RP y los contenidos hídricos del suelo. Los contenidos de N-NO3- en el suelo fueron mayores en los tratamientos testigos, independientemente del sitio, en tanto que los contenidos de N de la biomasa variaron entre 29 y 275 kg ha-1; con mayores valores para el centeno. La producción de soja varió entre 1069 y 5346 kg ha-1 y no se afectó por la inclusión de CC. Estudios futuros deben, en el largo plazo, contemplar el beneficio de la incorporación de CC sobre las propiedades físicas y químicas del suelo en sistemas agrícolas de la región semiárida y subhúmeda pampeana dedicados al cultivo de soja. / The soil productivity can be limited because of a frequent presence of oil crops and because of their little residue cover production and persistence on the soils. In the semiarid and subhumid Pampas region, the use of winter cover crops (CC) could provide residues with high C contents and maintain an adequate soil residue cover. But, the soil water use of the CC during the winter season can modify the normal soil water availability for the follo-wing crop. The objective of this research was to evaluate the dry matter (MS) production efficiency of winter cereals cultivated as CC and their effect on the soil available water and soil nitrates under two soil moisture regimes. The study was performed in four experimental sites: Luan Toro (La Pampa) (Entic Haplustoll, mean anual rainfall of 624 mm), Dorila (La Pampa) (Entic Haplustoll, mean anual rainfall of 873 mm), General Villegas (Buenos Aires) (Thapto-argic Hapludoll, mean anual rainfall of 906 mm)and General Pinto (Buenos Aires) (Typic Argiudoll, mean anual rainfall of 1116 mm). The treatments were: Rye [Secale cereale (C)], Rye grass [Lolium multiflorum (R)] and oat [Avena sativa (A)] and an untreated control without CC (T). The MS production at the moment of killing the CC varied between 1226 and 10500 kg ha-1. A strong effect of the soil water regime on the MS production of the CC was observed. The soil water content at the moment of seeding the CC explained 57 % of the MS production and the soil water content at seeding and rainfalls during the CC growing season explained almost 89 % of the variability in MS production. In the four locations, rye showed the greater MS production followed by oat and rye grass. The greater variability was observed within each of the sites and the studied seasons. The water uptake at the moment of killing the CC varied between 88 and 299 mm. Rye was the cereal with greater water use efficiency with a highest value in General Pinto with 54 kg of MS mm-1. The soil penetration resistance (RP) values were higher under CC treatments and negatively related with the soil mois-ture contents. Only in Dorila the highest values of RP were observed in the control treatment without a significant relationship between them and the soil water contents. The soil N-NO3- contents were greater in the T than in the CC treatments. The N content of the CC biomass varied between 29 and 75 kg ha-1 achieving greater values with rye. The soybean grain production varied between 1069 and 5346 kg ha-1 without differences due to the CC treatments. Future studies should study the effects of the CC use of physical and chemical soil properties in agricultural systems from the semiarid and subhumid pampas region under continuous soybean crop production.
690

THE SPATIALITY IN STORYTELLING

Yu, Xiang 13 July 2016 (has links) (PDF)
Theatre has always been played a irreplaceable role in people’s lives, even nowadays where people have multiple choices for entertainment. Some theater architecture has also become the symbol of the city, such as Paris Opéra and Sydney Opera House. By taking a close look at various case studies, one will understand how the theatre architecture corresponds with their city representing its history, culture and visions for the future. The development of my thesis is based on the integration of the ‘space’ of storytelling and the space of design. Will the quality of space bring out the memories that have been stored with in it? How the space provide with most flexibility for its users? Explorations in acoustic and lighting design as well as the spectators’ experience in the space will be discussed. My attention is to create a design that will heighten perception and arouse the audience’s sensory experience even before the start of the show. The relationship between nature and the architecture is also one of my attentions. Questions arise such as how to use a multidisciplinary approach to investigate the intersection of architecture and landscape. Should the architecture become a new definition towards the context or an expression that abstract from the landscape? This thesis explores the relationship between the performer and audience, and how the architecture space can contribute to the theater experience. The design for this project offers one solution for the whole site serving as a place for performing arts as well as a public space and a destination for the city of Boston.

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