Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xvi, 357 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 132-124).

La betterave sucrière est une plante bisannuelle dont le besoin de vernalisation est absolu. Ce processus correspond à l’acquisition de l’aptitude à la montaison et à la floraison et résulte d’une exposition prolongée à de basses températures. La durée de froid requise pour induire la montaison puis la floraison varie suivant les génotypes et reflète leur tolérance à la montaison, qui constitue donc un caractère agronomique essentiel. Cette thèse visait à (i) mettre en évidence un éventuel contrôle épigénétique (méthylation ADN) de l‘induction de la montaison chez des génotypes de betterave sucrière résistants ou sensibles à la montaison, (ii) identifier les séquences ciblées par des remaniements de méthylation de l’ADN et d’expression associés, et (iii) caractériser certaines séquences candidates en vue de leur utilisation comme marqueurs de la montaison. Nos travaux ont montré que l’amplitude et la cinétique des variations de méthylation de l’ADN observées au cours de la vernalisation semblent être des éléments critiques de l’induction et de la tolérance à la montaison. Par une approche ciblée, des séquences dont la méthylation de l’ADN est remaniée ont été identifiées. L’implication dans la transition florale de deux BvRNMT (RNA METHYLTRANSFERASES) et de la méthylation des ARN, tels que l’ARNm de BvFL1, un répresseur floral, a ainsi été mise en évidence chez la betterave sucrière. Enfin, grâce à une approche génomique, un réseau de gènes intégratif incluant la réponse à l’environnement, la signalisation hormonale et l’induction de la floraison a été identifié. La cinétique d’activation de ces gènes définirait le niveau de tolérance à la montaison des différents génotypes de betterave sucrière. / Sugar beet is a biennial plant with an absolute requirement of vernalization, corresponding to the acquisition of the competence to bolt and flower after a prolonged exposure to low temperatures. The cold duration needed to induce bolting and flowering varies depending on the genotypes, reflecting their bolting tolerance, which is an essential agronomic trait. This work aimed at (i) investigating a possible epigenetic control of bolting induction in bolting sensitive and bolting resistant sugar beet genotypes, (ii) identifying sequences targeted by DNA methylation and expression remodeling, and (iii) characterizing candidate sequences which could be used in marked-assisted selection for plant breeding. Our data suggest that the time course and amplitude of DNA methylation variations are critical points for the induction of sugar beet bolting and represent an epigenetic component of the genotypic bolting tolerance. In addition, we identified differentially methylated sequences exhibiting variations of gene-body DNA methylation and expression during cold exposure and/or between genotypes. Among them, two RNA METHYLCYTOSINE TRANSFERASES, in association with RNA methylation such as BvFL1 mRNA, a floral repressor, were shown to play a role in floral transition. Finally, using microarrays we identified an integrative network of genes including response to environment, phytohormone signalling and flowering induction. The activation kinetics of these genes could define the bolting tolerance level of sugar beet genotypes.

The Fully Encapsulated Resin Bolt (FERB) is widely utilised for strata control and ground support in civil and mining applications worldwide, with approximately 6 million installed per annum by the Australian coal mining industry. Independent studies have concluded that 30-35% of these rockbolts, which represents an annual expenditure of $40 million, are ineffective. The anchorage and failure mechanisms of FERB are yet to be quantified, and support systems are designed primarily from empirical rather than scientific methods. There are no standardised methods of assessing FERB components, installation techniques and support behaviour. The majority of research into FERB support systems remains commercial intellectual property, with little information released into the public domain. This thesis investigated several variables of FERB support systems, and also examined differences between field and laboratory pull-out test load distributions. This research was conducted in two phases, with Phase 1 seeking standardised methodology and repeatability in results, while Phase 2 further refined Phase 1 methods and extended the range of tests. The results in both phases were encouraging, with reasonable repeatability attained in all testing series. The findings included: ??? Annulus Thickness: There was little change in load capacity with small annulus thickness, however the maximum peak load (MPL) significantly reduced once annulus thickness exceeded 4mm ??? Resin Installation Spin Time: Underspinning of cartridge resin was found to have an insignificant effect on rockbolt load/deformation characteristics. Overspinning, however, led to a dramatic reduction in anchorage performance with a lessening in both MPL and stiffness ??? Rockbolt Load Transfer: The magnitude of an applied load reduced to zero along the length of the rockbolt, being greatest nearest the rock free surface (the point of load application). An exponential reduction was found when tested in the manner of laboratory tests, with the loading jack reacting against the free surface. This reduction was linear when the load was applied as in the field, with no load placed on the free surface This basic investigation into FERB support systems has validated many empirical understandings of rockbolts, while highlighting the need for further testing into several key areas.

The Fully Encapsulated Resin Bolt (FERB) is widely utilised for strata control and ground support in civil and mining applications worldwide, with approximately 6 million installed per annum by the Australian coal mining industry. Independent studies have concluded that 30-35% of these rockbolts, which represents an annual expenditure of $40 million, are ineffective. The anchorage and failure mechanisms of FERB are yet to be quantified, and support systems are designed primarily from empirical rather than scientific methods. There are no standardised methods of assessing FERB components, installation techniques and support behaviour. The majority of research into FERB support systems remains commercial intellectual property, with little information released into the public domain. This thesis investigated several variables of FERB support systems, and also examined differences between field and laboratory pull-out test load distributions. This research was conducted in two phases, with Phase 1 seeking standardised methodology and repeatability in results, while Phase 2 further refined Phase 1 methods and extended the range of tests. The results in both phases were encouraging, with reasonable repeatability attained in all testing series. The findings included: ??? Annulus Thickness: There was little change in load capacity with small annulus thickness, however the maximum peak load (MPL) significantly reduced once annulus thickness exceeded 4mm ??? Resin Installation Spin Time: Underspinning of cartridge resin was found to have an insignificant effect on rockbolt load/deformation characteristics. Overspinning, however, led to a dramatic reduction in anchorage performance with a lessening in both MPL and stiffness ??? Rockbolt Load Transfer: The magnitude of an applied load reduced to zero along the length of the rockbolt, being greatest nearest the rock free surface (the point of load application). An exponential reduction was found when tested in the manner of laboratory tests, with the loading jack reacting against the free surface. This reduction was linear when the load was applied as in the field, with no load placed on the free surface This basic investigation into FERB support systems has validated many empirical understandings of rockbolts, while highlighting the need for further testing into several key areas.

Thesis (M. E.)--University of New South Wales, 2003. / "The precursor to this thesis was an industry-sponsored project, completed in 2000 by C. Offner at the School of Mining Engineering, UNSW ; this project is referred to as the Stage 1 project"--summary. Also available online.

Thesis (M.Eng.(Mechanical and Aeronautical Engineering))--University of Pretoria, 2008. / Includes bibliographical references.

Thesis (Ph. D.)--Missouri University of Science and Technology, 2008. / Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed June 1, 2009) Includes bibliographical references (p. 229-234).

Thesis (Ph. D.)--West Virginia University, 2006. / Title from document title page. Document formatted into pages; contains xviii, 193 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 191-193).

Made available in DSpace on 2014-06-11T19:26:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-08-15Bitstream added on 2014-06-13T20:55:00Z : No. of bitstreams: 1 galvani_r_me_botfca.pdf: 554773 bytes, checksum: a7b1cacd2c35afbb04cdfab3f01e2772 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Outra / Com o objetivo de estudar a variabilidade genética para florescimento prematuro e outras características em uma população de cenoura ‘Brasília’ com produção de sementes sem necessidade de vernalização, foram estimados parâmetros genéticos em três ciclos de seleção em semeadura de outono-inverno. Os três ciclos foram avaliados simultaneamente num único experimento, em 2007, na Fazenda Experimental da Faculdade de Ciências Agronômicas, Campus de Botucatu/UNESP, localizada no município de São Manuel/SP a 22º44’50” de latitude Sul e 48º34’00” de longitude Oeste. Os tratamentos foram constituídos por 48 progênies de meios-irmãos do ciclo original de seleção, 48 progênies de meios-irmãos do primeiro ciclo de seleção, 50 progênies de meios-irmãos do segundo ciclo de seleção e oito testemunhas comuns para os três ciclos: ‘Nantes’, ‘HT-2000’, ‘Shin Kuroda’, ‘Brasília’ de quatro diferentes procedências e ‘Londrina’. Utilizou-se o delineamento experimental de blocos ao acaso, com 3 repetições e parcelas de 2m2 constituídas de oito sulcos transversais de semeadura espaçados de 25 cm de distância. A colheita foi feita 100 dias após a semeadura, com exceção das testemunhas ‘Nantes’ e ‘Shin Kuroda’, que por serem mais tardias foram colhidas aos 120 dias após a semeadura. Durante a colheita as raízes foram separadas em comerciais, apresentando comprimento de 17 a 25 cm e menos que 5 cm de diâmetro, sem a presença de cenouras deformadas, deterioradas, quebradas, rachadas e com outros defeitos que as tornem impróprias para o consumo, em refugo, isto é, fora dos padrões comerciais, e em raízes que apresentavam florescimento prematuro. A produção comercial, expressa em gramas, foi avaliada ao nível de parcela e obtida através da massa de raízes comerciais, a produção total, expressa em gramas,... / To study the genetic variability for bolting and other characteristics in ‘Brasilia’ carrots with production of seeds without vernalization, genetic parameters in three cycles of selection in autumn-winter sowing were estimated. The three cycles were evaluated simultaneously in only one experiment in 2007 in the Experimental Farm of the Agronomy School, Botucatu/UNESP Campus, in São Manuel/SP (22ºS44' and 48ºW34'). The treatments were constituted by 48 lineages of half-sibling from the original cycle of selection, 48 lineages of half-siblings of the first cycle of selection, 50 lineages of half-siblings from the second cycle of selection and eight witnesses for the three cycles: ‘Nantes’, ‘HT-2000’, ‘Shin Kuroda’, ‘Brasilia’ from four different origins and ‘Londrina’. The experimental outline of randomized blocks was used, with 3 replications and 2m2 lots of eight sowing transversal ridges spaced out at 25cm of distance. Harvest was carried out 100 days after sowing, exception for ‘Nantes’ and ‘Shin Kuroda’ witnesses, which for being late crops had to be harvested 120 days after sowing. During the harvest the roots were separated in commercials, presenting length of 17 the 25cm and less than 5cm of diameter, without the presence of deformed, spoiled carrots, broken, cracked or any other defects for consumption, in rubbish roots, that is out of commercial standards, and in roots presenting bolting. The commercial production, expressed in grams, was evaluated to the level of lots and obtained by the mass of commercial roots. The total production, expressed in grams, was obtained by the addition of the mass of commercial roots and rubbish, except those with premature floral connecting rods. Also obtained the percentage of rubbish mass, the percentage of plants not bolting and the percentage of orange shoulder in relation to the commercial production...(Complete abstract click electronic access below)

M.Ing.(Electrical and Electronic Engineering) / The study investigated whether non-destructive impact testing, aided by supervised machine learning methods, could be used to identify improper roof bolt installations, related to insufficient grout coverage. The testing method involved the installation of four roof bolts, with varying installation properties, into a 1511 × 940 × 1350mm rock test block. Three fully grouted bolts served as examples of proper installations, with the fourth bolt grouted only up to half the length of the borehole serving as an improper roof bolt installation. The testing procedure involved placing sensors directly onto the bolts and mechanically impacting a chosen bolt while measuring the response on all the bolts. The focus was on gaining understanding of the working principle of the testing technique and how the measured response was influenced by the presence of signal-modifying factors of the physical test block geometry, such as changes in material properties, boundary changes, cracks or empty boreholes. It was shown that the roof bolt integrity testing method aided by supervised machine learning methods could identify and classify both properly and improperly grouted roof bolts on the small sample of test bolts, in a series of tests conducted at the CSIR Centre for Mining Innovation premises. The method was also shown to be robust enough to do so even in the presence of the signal-modifying factors of the physical test block geometry.