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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.
111

Mass Transfer with Chemical Reaction From Single Spheres

Houghton, William 10 1900 (has links)
<p> Forced convection mass transfer rates from single gas bubbles, with accompanying chemical reaction, were determined experimentally in the intermediate Reynolds number range. The reacting system carbon dioxide-monoethanolaminc was chosen for this study. </p> <p> A mathematical model, describing forced convection mass transfer from a single sphere with accompanying first or second order reaction, was developed and solved using finite-difference techniques. Hydrodynamic conditions in the intermediate Reynolds number region were described using Kawaguti-type velocity profiles. </p> <p> The numerical solutions of the model have been compared with the experimental results of this study as well as with previous theoretical and experimental results. </p> / Thesis / Doctor of Philosophy (PhD)
112

Comparing likelihood ratios of complex DNA profiles using DNA-view mixture solution

Juodvalkis, Joseph R. 04 February 2023 (has links)
The DNA technology applied to forensic science has improved significantly in recent years. As a result of these advancements, DNA profiles can be generated from a low-template amount of DNA. This advancement, however, can lead to more complex mixtures due to the instrumentation picking up trace amounts of DNA. This leads to the need for these more challenging profiles to be interpreted. Due to the lack of standardization in DNA profile interpretation, one complex DNA profile is likely to draw several different conclusions from DNA analysts when assessing the number of contributors (NoC). Probabilistic genotyping software (PGS) is a possible solution to the problems of complex DNA profile interpretations. DNA-View® Mixture Solution™, developed by Dr. Charles Brenner, is a continuous modelling PGS that considers genotypes, peak height, stutter, dropout, and other artifacts that result from stochastic effects in the interpretation of DNA profiles. Mixture Solution has the potential to minimize some of the uncertainty inherent in DNA analysis of profiles having multiple contributors. In this project, DNA mixture analysis with Mixture Solution was applied to two and three-person mixtures having ratios ranging from 1:1 to 8:1 and 1:1:1 to 8:1:8. Two scenarios with several hypotheses were tested regarding each contributor as if they were the person of interest (POI) in a real case. Mixture Solution assigns the most favorable hypothesis for and against the POI and calculates an LR representing the comparison of those two hypotheses. In the final reports, trends previously observed in two-person mixture ratios were also observed in three-person mixtures. The main factor driving low LR assignment in three-person mixtures is low template DNA. Low peak heights and dropout are the factors driving low LR assignment. The factors that make manual DNA profile interpretation challenging can also challenge PGS. However, the robustness of Mixture Solution was demonstrated throughout the project with complex three-person mixtures.
113

A Study of Multi-Look ATR for HRR Signatures

Sehgal, Ankur January 2000 (has links)
No description available.
114

Assessment of the diffraction efficiency of novel barrier profiles using an MLS based approach

Watts, Gregory R., Morgan, P., Surgand, M. 29 May 2009 (has links)
No / In recent years there has been growing interest in the use of noise barrier profiles that can enhance the diffraction efficiency of plane barriers. These are placed on the top of the barrier in order to reduce sound diffracted into the shadow zone. A variety of shapes have been tested including T-shapes, multiple-edges and various cylindrical configurations. Despite numerous demonstrations that the profiles enhance performance there is no universal agreement on how the improvements can be quantified and incorporated into noise prediction models. Without such quantification it is likely that such profiles will not receive widespread acceptance. TRL has carried out an experimental investigation of the performance of novel-shaped barriers for the Transport Research Foundation. The approach relies on quantifying diffraction efficiency in the near field using a novel application of the Maximum Length Sequence (MLS)-based method. Measurements on 4 different profiles were taken in the vertical plane perpendicular to the barrier face. Two source and four receiver positions were used and results were obtained under a range of wind conditions. Results show large differences between the efficiency of the different options with the absorptive T-shaped and multiple-edge profiles performing best.
115

Identifying the nature of domestic load profile from a single household electricity consumption measurements

Ihbal, Abdel-Baset M.I., Rajamani, Haile S., Abd-Alhameed, Raed, Jalboub, Mohamed K. 2011 March 1922 (has links)
Yes / Detailed electricity load profile for domestic building is an important requirement for the accurate analysis of demand side management. The use of electrical appliances within domestic buildings varies significantly with respect to time, mainly in accordance with the activity and behaviour of the occupants. This paper presents results from a monitoring study of electrical energy consumption profiles for One UK household (two adults with children). Measurements for whole household electricity consumption have been obtained over a period of ten months. They were all obtained at one minute interval. Monthly energy consumptions, daily and overall profiles were derived for this household type from the monitored data. It is intended that the results presented in this paper can be used in the quest for a precise forecast method for electricity consumption for occupants living in the same type of household in the UK. This will allow greater confidence in the sizing of, e.g., adopting renewable energy sources in this type of household. Further investigation is needed for a large sample of households to improve the understanding of monitoring high resolution domestic energy consumption. / MSCRC
116

Investigating the impact of discomfort in load scheduling using genetic algorithm

Anuebunwa, U.R., Rajamani, Haile S., Pillai, Prashant, Okpako, O. 24 November 2016 (has links)
Yes / Energy consumers oftentimes suffer some element of discomfort associated with the implementation of demand response programs as they aim to follow a suggested energy consumption profile generated from scheduling algorithms for the purpose of optimizing grid performance. This is because people naturally do not like to be told what to do or when to use their appliances. Although advances in renewable energy have made the consumer to also become energy supplier, who can actively cash in at times of the day when energy cost is high to either sell excess energy generated or consume it internally if required, thereby nullifying the adverse effect of this discomfort. But a majority of consumers still rely wholly on the supply from the grid. This impact on users' comfort who are active participants in demand response programs was investigated and ways to minimizing load scheduling discomfort was sought in order to encourage user participation.
117

Neurobiological Underpinnings of Autistic Traits, Sensory Processing, and Mental Health in Young Adult Males and Females

McQuarrie, Miranda Jane 07 May 2024 (has links) (PDF)
Females may present with autism more frequently than is diagnosed, due, in part, to autistic trait and sensory processing differences. Unfortunately, recruiting enough autistic female participants is difficult, because of such underdiagnoses. By approaching autism as a continuous variable, neurotypical (NT) individuals can be studied to better understand autistic individuals. Thus, to examine potential neurobiological underpinnings of sex-based behavioral profiles, we recruited 52 NT individuals (22 male; 30 female). Participants underwent resting-state functional magnetic resonance imaging (fMRI) to examine how functional network connectivity (via group independent components analysis) underpinned overall male/female differences in previously measured behavioral autistic trait and sensory processing questionnaire scores. Results showed that males' sensory processing and autistic trait patterns were correlated with sensorimotor and social brain areas while females' intolerance of uncertainty and autistic traits were correlated with areas implicated in sensory processing and anxiety. Additionally, both sexes exhibited a close relationship between sensory processing (e.g., auditory, higher order visual), social functioning (e.g., middle temporal gyrus), and empathizing (e.g., right temporal-parietal junction, fusiform gyrus), though the networks present within these correlations differed somewhat between the sexes. Systemizing was most strongly correlated with executive functioning and language processing areas in both sexes, with different brain networks showing greater significance in males than females. Overall, males and females displayed similar neurophysiological patterns involved in autistic traits, sensory processing, empathizing, and systemizing, though they seemed to activate these networks differently. Understanding these network differences in an autistic population may provide for sex-specific brain-based interventions for sensory processing, anxiety, and autistic trait manifestation.
118

An opto-electronic soil profile meter

Khorashahi, Javad January 1986 (has links)
A mechanical, non-contact soil profile meter was developed to measure soil elevations before and after an artificial rainfall for erosion studies. The design goals were to measure the heights of the soil in a 1.5 x 1.5 m bin with an accuracy of ±1.0 mm and at a data collection rate of 2 points per second. The profiler consisted of a laser and a digital camera for height measurements, and a drive system for horizontal movement. The device was calibrated to determine the accuracy of horizontal positioning and the error associated with the height measurements. The positioning accuracy of the profiler was ±0.12 mm and the calibrated height error was ±0.68 mm. The rate of data collection was 32 points per minute. The calibrated height measurement unit was tested with actual soil samples. The analysis of the data collected from 9 different soil colors at 3 different heights and 5 different locations along the profiler indicated that color, rod deflection, and vertical distance between the lens and the surface affected the height measurements. The error for absolute heights was 1.2 mm and the error for the difference in heights was 0.2 mm. The outdoor performance of the profiler was also checked and the result was satisfactory. / M.S.
119

Mathematical Models of Hepatitis B Virus Dynamics during Antiviral Therapy

Carracedo Rodriguez, Andrea 21 April 2016 (has links)
Antiviral therapy for patients infected with hepatitis B virus is only partially efficient. The field is in high demand for understanding the connections between the virus, immune responses, short-term and long-term drug efficacy and the overall health of the liver. A mathematical model was introduced in 2009 to help elucidate the host-virus dynamics after the start of therapy. The model allows the study of complicated viral patterns observed in HBV patients. In our research, we will analyze this model to determine the biological markers (e.g. liver proliferation, immune responses, and drug efficacy) that determine the different decay patterns. We will also investigate how such markers affect the length of therapy and the amount of liver damage. / Master of Science
120

Performance and Microbial Profiles of Broiler Chickens fed Phytogenic Feed Additives or Probiotics during Coccidiosis

White, Mallory B. 06 February 2018 (has links)
The prophylactic use of antibiotics is rapidly being phased out of poultry operations. Diseases such as coccidiosis are extremely costly, and typically prevented with coccidiostats and antibiotics. New regulation banning antibiotics is mandating a search for new alternatives, such as probiotics and phytogenic feed additives (PFAs). Two separate studies were performed to evaluate the performance and microbial profiles of commercial broilers fed either PFAs or Eimeria challenged broilers fed probiotics. During the probiotics study, 1056 day-old male Ross broiler chicks were assigned to one of 6 treatments, 8 replicates per treatment, with 22 birds per floor pen in a 2x3 factorial arrangement, with DFM mix and coccidiosis challenge being the main factors. Treatments included a non-infected control (NC), a non-infected low level DFM-fed group (DL), a non-infected high level DFM-fed group (DH), an infected control (PC), an infected low level DFM-fed group (DL+), and an infected high level DFM-fed group (DH+). Performance measurements were taken on d0, d7, d14, d21, and d28. Mucosal scrapings from the ileum were obtained on d7, d14, d21, and d28 to determine microbial profiles. On d15, birds in the three infected groups were challenged with a mixed inoculum containing Eimeria maxima, E. tenella, and E. acervulina. Lesion scores were assessed on d21. Body composition was analyzed via Dual Energy X-Ray Absorptiometry (DXA) on d28. Results indicated a trend (P < 0.1) toward improved D28 body composition, lower Clostridium in DFM-fed challenged broilers compared to PC, and higher Bacillus in DH compared to DH+. Results were not significant for BW, BWG, FI, or lesion scores. The second study evaluated the effects of PFA provided as a dietary supplement over a 6-week period on performance and immune responses in broilers. In total, 1056 day-old male chicks were randomly assigned to 8 replicate pens (22 birds/pen) with 6 treatments including a standard corn/wheat basal diet, a basal with antibiotics, and 4 various combinations of PFA (PHY 1, 2, 3, and 4). Performance was assessed on day 7 (D7), 14, 28, and 42. Starter diet was fed D0-14, grower D14-28, and finisher D28-42. Microbial profiling was assessed on D7, 14, and 42, and body composition measured on D42 using Dual Energy X-Ray Absorptiometry (DXA). Results varied by week, but cumulatively, body weight gain (BWG) per bird was higher in PHY1 and 4, statistically similar to AGP and CTRL. With feed conversion ratio (FCR), PHY2 was higher than any other treatment between D0-42, while all other treatments were similar. PCR results were not statistically significant; however, DXA results indicated a higher lean to fat ratio in birds from PHY1-4 when compared to AGP, indicating an overall leaner bird in PHY treatments. The results of these studies suggest that diets supplemented with DFMs or PFAs result in improved broiler performance. / Master of Science / The prophylactic use of antibiotics is rapidly being phased out of poultry operations. Diseases such as coccidiosis are extremely costly, and typically prevented with coccidiostats and antibiotics. New regulation banning antibiotics is mandating a search for new alternatives, such as probiotics and phytogenic feed additives (PFAs). Two separate studies were performed to evaluate the performance and microbial profiles of commercial broilers fed either PFAs or Eimeria challenged broilers fed probiotics. During the probiotics study, 1056 day-old male Ross broiler chicks were assigned to one of 6 treatments, 8 replicates per treatment, with 22 birds per floor pen in a 2x3 factorial arrangement, with DFM mix and coccidiosis challenge being the main factors. Treatments included a non-infected control (NC), a non-infected low level DFM-fed group (DL), a non-infected high level DFM-fed group (DH), an infected control (PC), an infected low level DFM-fed group (DL+), and an infected high level DFM-fed group (DH+). Performance measurements were taken on d0, d7, d14, d21, and d28. Mucosal scrapings from the ileum were obtained on d7, d14, d21, and d28 to determine microbial profiles. On d15, birds in the three infected groups were challenged with a mixed inoculum containing Eimeria maxima, E. tenella, and E. acervulina. Lesion scores were assessed on d21. Body composition was analyzed via Dual Energy X-Ray Absorptiometry (DXA) on d28. Results indicated a trend (P < 0.1) toward improved D28 body composition, lower Clostridium in DFM-fed challenged broilers compared to PC, and higher Bacillus in DH compared to DH+. Results were not significant for BW, BWG, FI, or lesion scores. The second study evaluated the effects of PFA provided as a dietary supplement over a 6-week period on performance and immune responses in broilers. In total, 1056 day-old male chicks were randomly assigned to 8 replicate pens (22 birds/pen) with 6 treatments including a standard corn/wheat basal diet, a basal with antibiotics, and 4 various combinations of PFA (PHY 1, 2, 3, and 4). Performance was assessed on day 7 (D7), 14, 28, and 42. Starter diet was fed D0-14, grower D14-28, and finisher D28-42. Microbial profiling was assessed on D7, 14, and 42, and body composition measured on D42 using Dual Energy X-Ray Absorptiometry (DXA). Results varied by week, but cumulatively, body weight gain (BWG) per bird was higher in PHY1 and 4, statistically similar to AGP and CTRL. With feed conversion ratio (FCR), PHY2 was higher than any other treatment between D0-42, while all other treatments were similar. PCR results were not statistically significant; however, DXA results indicated a higher lean to fat ratio in birds from PHY1-4 when compared to AGP, indicating an overall leaner bird in PHY treatments. The results of these studies suggest that diets supplemented with DFMs or PFAs result in improved broiler performance.

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