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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.
71

Optical and Mechanical Characterization of Optical Fibers and Fiber Cables

Cervin, Andrew Claude January 1980 (has links)
This paper describes optical fiber and cable evaluation carried out at Bell-Northern Research during the summer period of May- August, 1980. Contemporary fibers and cables designed for telecommunications use were evaluated and the results on the following three areas are reported: (1) Resistance of fiber optics cables to temperature extremes and mechanical abuse. (2) Fiber tensile strength, both fast-fracture and fatigue, and a test method to predict longevity of the fibers. (3) Pulse broadening, measured as a function of link lengths in order to establish engineering rules which can predict performance for 10km lengths (typical repeater spacing) from the individual fiber characteristics. / Thesis / Master of Engineering (MEngr)
72

ANALYSIS OF BELL HOLE MORPHOLOGY AND DISTRIBUTION: A TOOL FOR EVALUATING FORMATIONAL PROCESSES

Dogwiler, Toby Joseph 07 August 1998 (has links)
Bell holes are described as vertical, cylindrical, dissolutional cave ceiling voids. Quantitative analysis of bell holes in San Salvador, Bahamas; Isla de Mona, Puerto Rico; Kentucky; and New York permit bell hole morphology to be contrasted in various geological settings and speleogenetic regimes. Mean bell hole height is 36 cm with a width of 34 cm and cross-sectional area of776 cm 2. Bell holes have elliptical openings, conical to cylindrical profiles, strong vertical development, and sometimes are associated with bell pits. Bell hole width remains constant between the study localities, but height varies. Several processes have been proposed to explain bell hole development: bat activity, condensation corrosion, phreatic degassing, vadose percolation, and phreatic convection cells. The vadose mechanisms seem unreasonable in light of bell hole morphology and setting. Thus, a phreatic process functioning in a laminar or slow-moving turbulent flow regime most likely accounts for bell hole formation.
73

Volatile generation in bell peppers during frozen storage and thawing using selected ion flow tube mass spectrometry (SIFT-MS)

Wampler, Brendan January 2011 (has links)
No description available.
74

Development and Effectiveness of Three Hydrocolloid-Lipid Emulsion Coatings on Preservation of Quality Characteristics in Green Bell Peppers

Ball, Jennifer Ann 23 April 1999 (has links)
Three hydrocolloid-lipid emulsion coatings were developed using Humkote brand partially hydrogenated cottonseed and vegetable oil, and one of three combined hydrocolloid bases: xanthan gum and propylene glycol alginate (xanthan coating), locust bean gum and xanthan gum (locust bean gum coating), and maltodextrin. Sensory testing using a ranking preference test indicated that these coatings had acceptable appearance and palatability. Quality characteristics of green bell peppers (Capsicum annum L. cv. King Arthur) measured during the 5-week storage period included: respiration rates, chlorophyll content, surface color, puncture force, pectin (uronic acid) content, ascorbic acid (AA) and dehydroascorbic acid (DHA) content, and cumulative weight loss. No significant differences between coated and uncoated peppers were noted in tests for respiration, puncture force, hue angle, chlorophyll content, and AA content. Uncoated peppers had significantly inferior moisture retention (p<0.05), which caused them to be unsaleable after 8 days, while coated groups were saleable for an additional 6 to 8 days. Uncoated fruits also had greater uronic acid breakdown (p<0.05) and higher DHA content (p<0.06) than coated peppers. Significant weekly changes (all treatment groups combined) included linear increases in respiration rates (p<0.01) and moisture loss (p<0.01), increasing linear and quadratic trends in uronic acid content (p<0.01 for both trends), increasing quadratic trends for both chlorophyll and AA content (p<0.05, p<0.01, respectively), and decreasing linear and quadratic (p<0.05 for both trends) in DHA content. The only significant difference between coated groups was in chroma value, with maltodextrin coated peppers appearing less vivid than locust bean coated peppers. Overall, all three coatings performed equally well during the storage study. However, coatings with higher lipid content, which included xanthan gum and locust bean gum groups, withstood humidity changes better than the maltodextrin coated peppers. Coating application provided the greatest benefits in terms of texture maintenance through water retention and prevention of pectin breakdown, despite the lack of differences observed in puncture force. Coatings may also have prevented AA oxidation as demonstrated by the higher DHA content in uncoated groups, however AA patterns do not confirm this concept. Future research should be directed toward further minimizing textural changes and maximizing coating durability. / Ph. D.
75

Evaluation of Two Lipid-Based Edible Coatings For Their Ability to Preserve Post Harvest Quality of Green Bell Peppers

Ball, Jennifer Ann 05 September 1997 (has links)
Two lipid-based edible coatings, Apex B (AC Humko, Memphis, TN) and Durafresh (Pacrite, Ecoscience Produce Systems, Orlando, Fl) were evaluated for their ability to preserve post harvest quality changes in green bell peppers (Capsicum annum L. cv. King Arthur). Post harvest storage quality conditions tested included respiration rates, weight, color and texture changes, and stability of ascorbic acid (AA) and dehydroascorbic acid (DHA) content. Results indicated that no appreciable changes between days or treatment groups occurred in three of the parameters tested: weight, texture, and hue angle (p>0.05 for all parameters). Significant weekly changes were seen in respiration rates, dehydroascorbic acid content, and chromaticity values. Respiration rates and DHA were significantly higher during the last two weeks of the study (p=0.0001, p=0.0001 respectively). Chromaticity values were significantly lower, indicating a more faded color on the 14th day of the study alone (p=0.0097). Initial AA levels were much lower than expected (average initial content=78.72mg/100g). Significant differences between coated and uncoated pepper groups were seen in AA and DHA levels. AA content was found to be significantly lower in coated peppers (p=0.0279), while DHA levels were significantly higher in coated groups (p=0.0126). Overall, coated groups differed little from uncoated counterparts, except in the area of vitamin content in which the coated peppers showed an increase in vitamin breakdown. Despite the results, modifications of lipid coatings are needed, such as creating bilayer and composite coatings that contain either polysaccharide or protein constituents to enhance coating effectiveness. / Master of Science
76

Putting Women Back on Top?: (Re)constituting Power and Audience in The Vagina Monologues

Gellert, Ashley Elizabeth 26 May 2011 (has links)
Eve Ensler's goal in writing The Vagina Monologues was to generate a dialogue regarding women's sexuality to counter the silence that pervades the patriarchal culture that they inhabit. To achieve this goal, Ensler constructs two ideologies—one grounded in patriarchy and another supposedly grounded in female agency and dialogue—to reveal the problems within the current ideology in hopes that her audience will adopt her new ideology and resolve the detrimental silence women endure. To evaluate its success, this study utilizes an eclectic approach—comprised of constitutive rhetoric, second persona, third persona, and bell hooks' rhetorical options—to determine if the play's content encourages the dialogue Ensler desires. / Master of Arts
77

The structural and chemical evolution of phyllic alteration at North Silver Bell, Pima County, Arizona

Piekenbrock, Joseph Robert January 1983 (has links)
No description available.
78

ESTIMATIVA DE CHUVAS INTENSAS NO RIO GRANDE DO SUL A PARTIR DAS RELAÇÕES GENÉRICAS DE BELL E CHEN / ESTIMATION OF HEAVY RAINS IN THE RIO GRANDE DO SUL FROM THE GENERIC RELATIONSHIPS OF BELL S AND CHEN S

Basso, Raviel Eurico 27 April 2015 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The knowledge of the relationship between intensity-duration-frequency (IDF relationship) of intense rainfall is of enormous importance for the design of engineering works. However, the availability of this data is limited, due to the scarcity of pluviographs data in Rio Grande do Sul (RS) or, when these exist, generally encompass small observation periods and/or with failures, which makes them useless to the determination of IDF relationships. In this scenario, we propose here to analyze the applicability in RS of the methodology suggested by Bell (1969) and Chen (1983). Bell (1969) proposed an equation for the entire planet, where intense rainfall, for any duration and return period, is determined based only on precipitation with return period of 10 years and duration of 1 hour, from anywhere we want determine. Bell (1969) is based on the fact that heavy rainfall are usually produced by convective systems that behave in a similar way regardless of the local of the precipitation. Numerous modifications of the methodology presented by Bell (1969) have already been carried out and presented as reliable results as Back (2009), Chen (1983), Ueahara et al. (1980) among others. In this study, the application of Bell s (1969) original equation, and some of his modifications was analyzed, introducing extra modifications still allowing its use with the rainfall data in RS. The results show that the methodologies of Bell (1969) and Chen (1983) are complementary because we obtained if good fits for durations shorter than 2 hours when applied Bell (1969) and when applied Chen (1983) presented best settings in durations greater than 2 hours. The biggest errors were found in the rainfall estimation for 2 years return period, because we also observed that both methodologies go through a heating process of the equation. To try and fill the entire State on the issue of intense rainfall, the regionalization of heavy rains in order to make more practical and reliable use, which presented good results only for the regions B, D and F, and in the other regions (A, C and E) the results were positive in only 60% of the sites studied. / O conhecimento das relações entre intensidade - duração - frequência (relação IDF) das chuvas intensas é de enorme importância para o projeto de obras de Engenharia. No entanto, a disponibilidade destes dados é limitada, devido à escassez de registros pluviográficos no Rio Grande do Sul (RS) ou, quando estes existem, geralmente abrangem pequenos períodos de observação e/ou com falhas, o que os torna sem utilidade para a determinação das relações IDF. Nesse cenário, se propõe aqui analisar a aplicabilidade no RS da metodologia sugerida por Bell (1969) e Chen (1983). Bell (1969) propôs uma equação para todo o planeta, onde a precipitação intensa, para qualquer duração e tempo de retorno, é determinada com base apenas na precipitação com tempo de retorno de 10 anos e duração de 1 hora, do local onde se quer determinar. A proposta de Bell se baseia no fato que chuvas intensas normalmente são produzidas por sistemas convectivos, que se comportam de forma semelhante independentemente do local da precipitação. Inúmeras modificações da metodologia apresentada por Bell (1969) já foram realizadas e apresentaram resultados confiáveis como Back (2009), Chen (1983), Ueahara et al. (1980) entre outros. Neste trabalho, avaliou-se a aplicação da equação de Bell (1969) original, e algumas de suas modificações, introduzindo ainda modificações extras que permitam a sua utilização com os dados pluviométricos existentes no RS. Os resultados mostram que as metodologias de Bell (1969) e Chen(1983) são complementares pois foram obtidos bons ajustes para durações menores que 2 horas quando aplicado Bell (1969) e enquanto Chen (1983) apresentaram melhores ajustes nas durações superiores a 2 horas. Os maiores erros foram encontrados na estimativa das precipitações para TR de 2 anos, pois observou-se também que ambas as metodologias passam por um processo de aquecimento da equação. Para tentar suprir todo o Estado na questão das precipitações intensas, realizou-se a regionalização das equações de chuvas intensas de forma a tornar mais prática e confiável a sua utilização, o qual apresentou bons resultados somente para as regiões B D e F, e nas demais regiões (A, C e E) os resultados foram positivos somente em 60 % dos locais estudados.
79

Změna v rovnováze BELL transkripčních faktorů jako nástroj posílení tuberizace u vybraných kultivarů bramboru / Modulation of BELL transcription factors balance as a tool for tuberisation strengthening in selected potato cultivars

Zounková, Andrea January 2019 (has links)
Potato (Solanum tuberosum) is the third most important crop in terms of human consumption. Hence understanding regulatory mechanisms controlling tuber initiation is significant not only from a theoretical but also practical point of view. Tuberization of S. tuberosum is a complex morphogenic process regulated by both, environmental conditions and inner plant status. Environmental conditions regulating the onset of tuberization have been known for a long time, but the molecular basis of tuber initiation has only recently been discovered, in particular using wild subspecies S. tuberosum subsp. andigena. BELL transcription factors are among the important components of the regulatory signalling network. The aim of this study was to modulate balance between the BELL transcription factors that induce and repress tuberization towards strengthening of tuber induction using two cultivars of Solanum tuberosum subsp. tuberosum, cv. Kamýk, resp. cv. Korela. To achieve this, transgenic lines carrying construct containing a part of coding sequence StBEL11, resp. StBEL29 in antisense orientation (AS) under control of constitutive promoters and lines carrying complete sequences of StBEL5 and StPTB6 genes under control of their native promoters were derived. We used the StBEL11 and StBEL29 AS constructs with the aim to...
80

Mobile wireless in Canada: policy, problems, and progress

Klass, Benjamin 01 September 2015 (has links)
The topic of this thesis is the institutional ecology surrounding mobile wireless telecommunication services in Canada. The primary focus is the disconnect between policy pronouncements promoting universal adoption of mobile services, on the one hand, and the fact that mobile adoption remains stubbornly low in both absolute terms and by international comparison. Key concepts in the theory of communication regulation and the historical development of telecommunication policy are laid out, which are used to inform an examination of the development of national mobile communication policy since the 1980s. The thesis then presents two case studies. The first is focused on recent developments in federal mobile policy, directed toward taking greater steps to ensure broad adoption of mobile services. The second examines the changing role of mobile services, from instruments of interpersonal communication to a broader form of information media, and the challenges that this shift has created for policymakers. / October 2015

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