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1
Kristjánsson, Gunnar. "Rock bolting and pull out test on rebar bolts." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for geologi og bergteknikk, 2014. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-25429.
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Pull out tests were carried out in the laboratory of rock mechanics at Norwegian University of Science and Technology (NTNU) for the purpose of determining the critical embedment length of fully grouted rebar bolts. The 20-mm rebar bolts and the grouting material, “the Rescon Zinc bolt cement” used in the testing are widely used in underground projects in Norway. Different embedment lengths, ranging from 10 cm to 40 cm, were employed in the tests under different water-cement ratios for the grouting mortar. The critical embedment length for a given water-cement ratio is determined on the diagram of the pull - out load versus the embedment length. A chart of the critical embedment bolt length versus the water-cement ratio as well as the uniaxial compressive strength of the cement mortar is established based on the testing results. In the theoretical part of the thesis, the main focus is on rock bolting. Bolting principals are introduced along with different types of rock bolts, design of bolting systems and stability problems caused by rock stresses. In the final part of the theoretical part the procedure of pull out testing is described and the load bearing capacity of rock bolts are categorized into the groups in accordance with load deformation performance. Finally, previous pull out test research is presented.
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Holmes, Helen Frances. "The role of gibberellin in bolting in sugar beet." Thesis, University of Cambridge, 2016. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709529.
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Dean, David L. "Design of a robotic end-effector for automated bolting." Thesis, Massachusetts Institute of Technology, 1985. http://hdl.handle.net/1721.1/100065.
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Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1985.MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING
Bibliography: leaf 111.
by David L. Dean, Jr.
M.S.
4
Taylor, Jemma Louise. "Delayed bolting in rocket for improved quality and greater sustainability." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/77863/.
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Wild rocket (Diplotaxis tenuifolia) has recently become a popular salad leaf in the UK due to its peppery taste. It is grown widely in Italy but is now being produced in Spring and Summer in England. It is part of the Brassicaceae family and thus has a high level of homology at the DNA level to other Brassica species and Arabidopsis. This project aims to produce late bolting genotypes of rocket to incorporate into commercial breeding programmes. Delayed bolting is important as current varieties flower at unpredictable times and often earlier than desired. This is a problem because when rocket flowers it becomes unsaleable. Ethyl methanesulphonate (EMS) was used to generate a mutant population of rocket. Late bolting lines were selected and whole genome sequencing was used to identify single nucleotide polymorphisms (SNPs) induced by the EMS which may be a cause of the late bolting phenotype. Six flowering pathway genes have been isolated from rocket and have been tested to see if they can functionally complement A. thaliana knockout lines in these genes. Further work was carried out to investigate how these genes were expressed over diurnal and developmental time courses to understand their function in the flowering time pathway in rocket. Together, these results show that most of the flowering pathway genes isolated from rocket are functional orthologues of those in Arabidopsis. The photoperiodic and vernalization requirements of rocket were investigated and it was found that rocket does not have a vernalization requirement and is a facultative long day plant. Targeted mutagenesis using clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR associated system (cas9) was employed for the introduction of mutations into the FLOWERING LOCUS T (FT) gene in rocket and Arabidopsis. Many late flowering Arabidopsis lines were identified and sequencing revealed the successful manipulation of the FT gene. Two late bolting rocket lines were also identified. Overall, the project aims were achieved as late bolting rocket lines have been produced and will be incorporated into a rocket breeding programme.
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Ahmed, Marfique. "Strengthening of reinforced concrete beams by bolting steel plates to their sides /." Title page, abstract and contents only, 1996. http://web4.library.adelaide.edu.au/theses/09ENS/09ensa286.pdf.
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Debenham, Gunnel Birgitta. "Bolting and flowering mechanisms in sugar beet, Beta vulgaris, ssp vulgaris (L)." Thesis, University of Nottingham, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.311840.
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Mirabile, Benjamin T. "Geologic feature prediction using roof bolter drilling parameters." Morgantown, W. Va. : [West Virginia University Libraries], 2003. http://etd.wvu.edu/templates/showETD.cfm?recnum=3216.
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Thesis (M.S.)--West Virginia University, 2003.Title from document title page. Document formatted into pages; contains xii, 84 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 83).
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Abbott, Aaron. "The isolation of flowering time genes from lettuce to enable the manipulation of bolting time." Thesis, University of Warwick, 2010. http://wrap.warwick.ac.uk/35099/.
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The time of bolting is an important factor in lettuce production because it affects the yield and quality of the harvested crop. Bolting is promoted by higher temperatures and is an increasing problem for growers with the current trend for warmer summers. Lettuce plants that are in the early stages of bolting are visibly indistinguishable from non-bolting plants, however there are changes in the biosynthesis of secondary metabolites which are produced to protect the young floral bud from insect attack. These compounds give the lettuce plant a bitter taste and render the crop unsaleable. The development of late bolting varieties, which would have a greater ‘holding ability’ in the field, would result in reduced crop losses and an extension to the growing season. In many plants, the timing of the transition from vegetative growth to flowering is controlled by environmental cues which serve to communicate growth conditions favourable for sexual reproduction and seed maturation. Studies in Arabidopsis have led to the identification of several different pathways that come together to regulate flowering time. Little research has been done on these response pathways in lettuce, however, research has shown that components of these pathways are conserved between Arabidopsis and other crop species. The aim of this project is to isolate genes regulating flowering time in lettuce in order that novel alleles of these genes can be used to manipulate bolting time. A lettuce BAC library has been screened and homologues of eight Arabidopsis flowering time genes, principally from the autonomous pathway, have been isolated. Functional orthologues of FLOWERING LOCUS T (FT) and the autonomous pathway gene, FLK have been characterised in lettuce, suggesting that there is conservation of the genes involved in flowering time in Arabidopsis and lettuce. Lettuce lines with a range of bolting times, including lines which bolt significantly later than wild-type have been identified from EMS mutagenised populations of cultivated lettuce and a diversity set of wild lettuce. Homozygous lines from a Lactuca sativa cv. Larissa EMS population with a reproducible late bolting phenotype when tested under commercial growing conditions have been identified. These lines have been made available to Rijk Zwaan® for inclusion in future breeding programs aimed at delaying bolting and improving the ‘holding’ ability’ of commercial lettuce crops. Genomic sequence of selected lettuce flowering time genes have been compared between the late bolting lines and wild-type looking for polymorphisms that may account for the late bolting phenotype. Polymorphisms within these genes were identified in some of the late bolting lines, however through analysing the polymorphism in segregating backcross populations they have been shown not to be causing the late bolting phenotype. Transcriptome sequencing has also been performed to identify polymorphisms in other, possibly novel, genes which may be causing the late bolting phenotype, as yet, no mutation segregating within the late bolting lines has been identified.
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Ramin, Ali Akbar. "Manipulation and predictive modelling of bolting and flowering in celery (Apium graveolens L. var. dulce)." Thesis, University of Nottingham, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.254417.
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Finfinger, Gerald L. "A methodology for determining the character of mine roof rocks." Morgantown, W. Va. : [West Virginia University Libraries], 2003. http://etd.wvu.edu/templates/showETD.cfm?recnum=2834.
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Thesis (Ph. D.)--West Virginia University, 2003.Title from document title page. Document formatted into pages; contains xv, 214 p. : ill. (some col.). Vita. Includes abstract. Includes bibliographical references (p. 92-94).
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Al-Said, Fahad Aljulanda. "The effect of temperature on growth, stem extension and bolting in iceberg lettuce (Lactuca sativa L.)." Thesis, University of Reading, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.312401.
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Pfeiffer, Nina [Verfasser]. "Genetic mapping of QTL for bolting time after winter in sugar beet (Beta vulgaris L.) / Nina Pfeiffer." Kiel : Universitätsbibliothek Kiel, 2017. http://d-nb.info/1124464522/34.
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Cote, John Christopher. "The impact of predevernalization and plasticulture treatments on bolting of celery (Apium graveolens L.) grown in Quebec /." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=33742.
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Vernalized celery seedlings (Apium graveolens L. var. Florida 683) were predevernalized under different temperature and light regimes prior to field transplanting. At least 89% of predevernalized plants bolted during both 1999 and 2000 suggesting that the predevernalization treatments were not effective in counteracting the vernalizing stimulus. Predevernalization treatments had no long-term effect on growth and development. Non-vernalized celery seedlings were transplanted on clear polyethylene mulch, thermo-selective polyethylene mulch or no mulch in combination with clear perforated polyethylene mini tunnel, single or double layer of agrotextile mini tunnel or no mini tunnel. Very few plants bolted in 1999. Mulch increased fresh weight and number of celery leaves compared with controls. Plants grown on clear polyethylene mulch had significantly higher mortality rates than other treatments. Agrotextile mini tunnels reduced bolting to 0% in 2000. Mini tunnels, especially a single layer of agrotextile, increased fresh weight, plant height and stem diameter in 2000.
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Buys, B. J. "Rock bolt condition monitoring using ultrasonic guided waves." Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-06222009-135318/.
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Frerichmann, Sebastian Leo Max [Verfasser]. "Detection of new sequence variants for flowering and bolting time genes in species of the genus Beta / Sebastian Leo Max Frerichmann." Kiel : Universitätsbibliothek Kiel, 2013. http://d-nb.info/1036242811/34.
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Nutakor, David. "Design and evaluation of a virtual reality training system for new underground rockbolters." Diss., Rolla, Mo. : Missouri University of Science and Technology, 2008. http://scholarsmine.mst.edu/thesis/pdf/Nutakor_09007dcc80672480.pdf.
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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).
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Dally, Nadine [Verfasser]. "Map based cloning and functional analysis of two bolting time loci BTC1 and BvBBX19 in sugar beet (Beta vulgaris L.) / Nadine Dally." Kiel : Universitätsbibliothek Kiel, 2014. http://d-nb.info/1053653506/34.
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Eichstädt, Rasmus [Verfasser]. "Fatigue assessment of large-size bolting assemblies for wind turbine support structures : Ermüdungsbewertung sehr großer Schraubenverbindungen für Tragstrukturen von Windenergieanlagen / Rasmus Eichstädt." Hannover : Gottfried Wilhelm Leibniz Universität Hannover, 2019. http://d-nb.info/1193177162/34.
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Galvani, Raquel [UNESP]. "Variabilidade para florescimento prematuro em cenoura ‘brasília’ no cultivo de outono-inverno." Universidade Estadual Paulista (UNESP), 2008. http://hdl.handle.net/11449/93485.
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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)
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Weckert, Steven Mining Engineering Faculty of Engineering UNSW. "Anchorage and encapsulation failure mechanisms of rockbolts ??? stage 2." Awarded by:University of New South Wales. School of Mining Engineering, 2003. http://handle.unsw.edu.au/1959.4/19219.
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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.
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Galvani, Raquel 1983. "Variabilidade para florescimento prematuro em cenoura 'brasília' no cultivo de outono-inverno /." Botucatu : [s.n.], 2008. http://hdl.handle.net/11449/93485.
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Orientador: Norberto da SilvaBanca: Antonio Ismael Inácio Cardoso
Banca: Paulo César Tavares de Melo
Resumo: 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,...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: 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)
Mestre
22
Broccanello, Chiara. "Biotechnology applications in sugar beet breeding." Doctoral thesis, Università degli studi di Padova, 2016. http://hdl.handle.net/11577/3424820.
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The aim of this thesis was to identify molecular markers associated to tolerance to biotic and abiotic stresses in sugar beet. Sugar beet is one of the world’s most important crops currently supplying around 20% of the sugar consumed worldwide. The crop is damaged by many adverse environmental conditions and the development of varieties that require fewer technical inputs for cultivation is one of the main research demands. To achieve this, sugar beet breeding is focusing on genetic improvement programs assisted by molecular markers. These methods are making selection procedures more rapid, accurate and less expensive. The development of a large set of SNP markers can facilitate the identification and exploitation of genes affecting important traits, such as resistance to biotic and abiotic stresses. Several techniques are used to enable SNP marker discovery in plants. Among these, the Restriction-site Associated DNA (RAD) technique is widely used. The RAD technique is based on acquiring and characterizing the genomic regions adjacent to a set of specific restriction enzyme recognition sites. Bulk Segregant Analysis (BSA) is a method to identify DNA markers linked to genes or genomic regions of interest. DNA samples from individuals showing contrasting phenotype are compared with a large set of molecular markers to select those linked to the trait of interest.
The first part of the thesis presents a panel of 192 SNPs for effective sugar beet genetic diversity assessment using a recently released platform (QuantStudio 12K Flex system coupled with Taqman OpenArray technology) that has key elements required for high-throughput SNP genotyping.
In the second part, the 192 SNPs were used to assess the phylogenetic relationship between Rizor and Holly (Rz1) resistance sources. The molecular results demonstrate that the resistances to rhizomania used by farmers over the last 30 years derived from sea beet collected in the Po River Delta. Analysis of molecular variance and principal coordinate analysis confirmed that Rizor and Rz1 couldn’t be distinguished as separate sources of resistance.
In the third part, a marker linked to the first nematode tolerance gene (HsBvm-1) from Beta vulgaris ssp. maritima valuable for high-throughput marker-assisted selection was identified and mapped on chromosome 5.
The fourth and fifth parts focus on resistance to abiotic stresses that compromise sugar production. Premature flowering or bolting, due to cold temperatures in early spring, is an undesirable characteristic that causes severe sugar yield losses and interferes with harvesting. A new locus involved in the genetic determination of bolting tendency was studied and a SNP marker associated with bolting tendency was found on chromosome 6. SNP location on the sugar beet genome confirms the association with flowering since it was mapped in a matrix metalloproteinase gene that causes late flowering and early senescence in Arabidopsis thaliana. Given the close and positive relationships between yield and root morpho-physiological traits, a BSA was conducted to identify a SNP marker linked to root elongation rate in sugar beet. SNP10139 was mapped on the peptide transporter gene influencing root elongation in Arabidopsis thaliana.
The result suggests that SNPs developed in these studies could serve as a source for genotyping of sugar beet parental lines and varieties, with relevant impact on breeding program decisions.Lo scopo della tesi è stato quello di identificare marcatori molecolari associati alla tolleranza a stress biotici e abiotici in barbabietola da zucchero. La barbabietola attualmente produce circa il 20% dello zucchero mondiale. Uno dei maggiori obiettivi del miglioramento genetico è lo sviluppo di varietà che richiedano un sempre più basso utilizzo di mezzi tecnici per la coltivazione. Per raggiungere questo scopo, il breeding della barbabietola si è focalizzato su programmi di miglioramento genetico assistito da marcatori molecolari. Queste tecniche stanno rendendo la procedura di selezione più rapida, precisa e meno costosa. Lo sviluppo di un ampio set di marcatori SNP (Single Nucleotide Polymorphism) può facilitare l’identificazione e l’utilizzo di geni che controllano caratteri importanti di resistenza agli stress biotici e abiotici. Molte sono le tecniche che vengono utilizzate per lo sviluppo di marcatori SNP nelle piante. Fra queste, la tecnica Restriction-site Associated DNA (RAD), impiegata nel presente lavoro di tesi, è ampiamente diffusa e si basa sull'acquisizione e la caratterizzazione di regioni genomiche adiacenti a siti di restrizione riconosciuti da specifici enzimi. E’ stata utilizzata anche l’analisi dei segreganti riuniti (BSA) per identificare marcatori del DNA legati a geni o a regioni genomiche di interesse. Nella prima parte della tesi è stato messo a punto un set di 192 SNP per la genotipizzazione ad alta processività di accessioni di barbabietola utilizzando una recente piattaforma (QuantStudio 12K Flex system) rilasciata da Life Technologies, Inc. (Carlsbad, CA, USA). Nella seconda parte della tesi i 192 SNP sono stati utilizzati per determinare la relazione filogenetica tra le due fonti di resistenza alla rizomania Rizor e Holly (Rz1). L’analisi della varianza e delle componenti principali hanno confermato che le fonti Rizor e Holly sono indistinguibili. I risultati molecolari hanno dimostrato che la resistenza usata, dai coltivatori negli ultimi 30 anni, deriva dalle barbabietole maritime collezionate nel delta del Po. Nella terza parte è stato identificato il primo gene di tolleranza ai nematodi (HsBvm-1) in Beta vulgaris spp. maritima e il marcatore molecolare ad esso associato da utilizzare in programmi di miglioramento genetico. La quarta e quinta parte sono state focalizzate sulla resistenza a stress abiotici che compromettono la produzione di zucchero. La tendenza alla prefioritura, dovuta alle basse temperature nelle prime fasi di sviluppo della coltura, è una caratteristica indesiderata che causa gravi perdite nella resa di zucchero e interferisce con la raccolta. Un nuovo locus, implicato nel controllo genetico della tendenza alla fioritura, assieme a un marcatore ad esso legato sono stati mappati sul cromosoma 6. La localizzazione dello SNP sul genoma di riferimento della barbabietola da zucchero ha confermato l’associazione con il carattere della fioritura. Lo SNP è stato mappato in un gene che codifica per una proteina chiamata metalloproteinasi che causa un ritardo della fioritura e una prematura senescenza in Arabidopsis thaliana. Data la positiva e stretta relazione tra la resa in zucchero, il superamento della carenza idrico nutrizionale e le caratteristiche morfo-fisiologiche dell’apparato radicale, un’analisi dei segreganti riuniti è stata condotta per identificare marcatori SNP legati all'accrescimento radicale in barbabietola. Fra i 234 SNP esaminati, lo SNP10139 è risultato associato allo sviluppo radicale. Inoltre, lo SNP è stato mappato in un gene codificante un trasportatore di peptidi che influenza lo sviluppo radicale in Arabidopsis thaliana. In conclusione, gli SNP sviluppati in questo lavoro saranno utilizzati per la genotipizzazione di linee parentali e ibridi di barbabietola da zucchero, con rilevante impatto nei programmi di breeding.
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Hounyevou, klotoe Mawudo Eirel Cédric. "Modélisation de l'influence des techniques de présoutènement sur les tassements provoqués lors du creusement des tunnels peu profonds." Thesis, Paris Est, 2017. http://www.theses.fr/2017PESC1107/document.
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Cette thèse porte sur l’utilisation de présoutènements pour réduire les tassements, c’est-à-dire la mise en place de boulons au front et d’une voute parapluie au-dessus du front. Elle cherche à fournir des outils pour évaluer l’impact des techniques de construction sur les tassements au moyen de calculs numériques par éléments finis. Une attention particulière est portée aux conséquences des choix de simulation sur les résultats obtenus.Le chapitre 1 présente une comparaison de différentes approches de simulation du creusement d’un tunnel peu profond en déformation plane. Les résultats ne justifient pas de privilégier les approches alternatives par rapport à l’approche classique qui utilise des forces de déconfinement. D’autre part, la disposition des présoutènements impose de réaliser des modélisations tridimensionnelles. Dans toute la suite du mémoire, on se place donc dans le cadre tridimensionnel. Dans un premier temps, le chapitre 2 présente une étude de l’influence de la géométrie du front de taille d’un tunnel sur sa stabilité : on compare le cas d’un front de taille vertical et d’un front de taille incliné ou courbe.Le chapitre 3 porte sur la prise en compte dans les simulations numériques du renforcement du front de taille par boulonnage. Nous avons comparé différentes approches, et montrer l’apport des modélisations qui prennent en compte de manière détaillée l’interaction sol-boulon, pour la simulation d’essais effectués en centrifugeuse.Dans le chapitre 4, on étudie l’influence des boulons au front sur les tassements. Nous avons cherché à discuter l’utilité de décrire en détail certains aspects du processus de construction, comme le cycle de renouvellement des boulons au front. Nous avons également discuté l’influence de la distance de pose du radier en arrière du front.Le chapitre 5 étudie l’influence de la voute parapluie sur les tassements. Nous avons établi une modélisation qui prend en compte la géométrie conique de la voute parapluie et du soutènement et le cycle de renouvellement des tubes de la voute. Enfin, on a proposé une modélisation originale du procédé de réduction des tassements au moyen d’injections réalisées à partir des tubes de la voute, appelé « présoutènement actif ».Les résultats fournissent des éléments pour le dimensionnement des procédés de présoutènements, en montrant, par exemple qu’il existe une valeur limite à partir de laquelle il n’est plus utile d’augmenter le nombre de boulons ou de tubes. Ils montrent également que certains choix de modélisation ont peu d’influence sur les tassements, ce qui justifie de prendre en compte des hypothèses qui simplifient la réalisation pratique des études numériques.La thèse a été financée par le projet FUI Newtun, piloté par Solétanche-BachyThis thesis focuses on the use of pre-reinforcements to reduce the settlements, namely the reinforcement of the tunnel face by bolts, or the installation of a pipe-roof umbrella placed above the face. It seeks to provide tools to evaluate the influence of the construction techniques on the settlements by means of finite element simulations. A special attention is paid to the consequences of the choices of simulation on the numerical results obtained.Chapter 1 presents a comparison between different approaches of simulation for the excavation of a shallow tunnel in plane strain. The results show that the alternative approaches do not give better results, in terms of width of the predicted settlement trough, than the classical approach based on excavation forces. On the other hand, the implementation of the pre-reinforcements imposes to carry out three-dimensional simulations. In this context, ones discusses, in chapter 2, the influence of the geometry of the tunnel face of a tunnel on his stability: we compare the case of a vertical tunnel face and with an inclined or curved tunnel face.Chapter 3 focuses on the techniques that can be used to take into account in the numerical simulations the reinforcement of the tunnel face by bolting. We have compared different approaches, and showed that models that take into account in more detail the soil-bolt interaction give better results for the simulation of centrifuge tests.In Chapter 4, we discuss the influence of the bolts on the settlements. We have discussed the utility of taking into account in the simulation some aspect of the construction process, such as the renewal of the bolts. Also, we have discussed the influence of the distance between the tunnel face and the invert.Chapter 5 studies the influence of the pipe umbrella on the settlements. We have established a model that takes into account the conical geometry of the pipe umbrella and the lining, and the cycle of renewal of the pipes. In the last place, we have proposed an original modelling of the technique of aiming at reducing the settlements by means of injections carried out from the pipes, called “active pre-reinforcement”.The results provide some elements for the design of the pre-reinforcement elements, and show for example that there exists a threshold value above which it is not useful to increase the number of bolts or of pipes. On the other hand, they show that some choices of simulation have little influence on the computed settlements, which justifies some assumptions that can be useful to reduce the complexity of three dimensional numerical models.The thesis has been funded by the project FUI Newtun (under the coordination of Solétanche-Bachy)
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Hebrard, Claire. "Contrôle épigénétique de l'induction et de la tolérance à la montaison chez la betterave sucrière." Phd thesis, Université d'Orléans, 2012. http://tel.archives-ouvertes.fr/tel-00872074.
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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.
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Pupík, Antonín. "Lávka pro chodce a cyklisty." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226075.
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This thesis deals with the design and assessment of footbridge for pedestrians and cyclists in the city of Hranice, Rybare district. The footbridge will serve as a crossing point over the river Bečva and will conect cycling trail with the street Rybarska. The content of this paper is to propose two different variants of structures. One of these options is selected based on their economic evaluation and further processed. Length of the bridge is 50m.
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Kounoudji, Komla Apelete. ""Intimité tribologique" des contacts d'un assemblage boulonné. Contrôle du serrage, du dévissage, ...des assemblages d'aéro-structures et conséquences sur leur conception." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI055/document.
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Depuis l'utilisation des boulons au XVème siècle pour assembler deux pièces, les assemblages boulonnés posent des questions quant à la compréhension de leur fonctionnement et de leurs défaillances, telles que la variation de la tension de serrage entrainant, le desserrage, le dévissage, la perte d'étanchéité, l'initialisation de fissures, ... Pour comprendre leur fonctionnement, une méthodologie d'analyse tribologique a été mise en place, permettant de démonter un assemblage boulonné sans le desserrer, afin de ne pas modifier les conditions de contact lors du desserrage. Ainsi, toutes les interfaces d'assemblages (‘‘filets’’ écrou/vis et ‘‘autres que filets’’) formant des triplets tribologiques, ont été étudiées durant les trois phases de leur cycle de vie (fabrication, serrage, service) par le biais de cas-tests de matériaux différents. Un dialogue interactif entre les expérimentations (corrélations d'images, expertises) et la simulation numérique (Eléments Finis, Eléments Discrets) a permis de dégager des interprétations, notamment concernant les trois phases. Lors de la fabrication, le roulage des vis engendre des transformations tribologiques superficielles au niveau des sous-surfaces des filets formés. Le cœur des vis (noyau) restant non-déformé, ce procédé crée ainsi une différence de microstructure au sein de ces vis, ce qui est une source d'altération de leurs propriétés en fatigue. Lors du serrage, il se forme à l'interface ‘‘filets’’ une mixture de troisièmes corps ‘‘sec-solide’’, accommodant la vitesse entre la vis et l'écrou. Cette mixture résulte d'une réactivité entre une graisse utilisée pour le serrage et des particules, détachées d'un revêtement appliqué sur les filets d'écrous et/ou de vis. En fin de serrage, une partie de la mixture reste piégée entre les filets, jouant le rôle de maintien de la tension de serrage. Dans ces conditions, il apparaît que le frottement varie en fonction de la rhéologie de la mixture, conditionnant la variation de la tension de serrage. En service, des instabilités de contact (glissement, décollement, ...) ont été identifiées au niveau des interfaces. Ces instabilités engendrent dans les interfaces ‘‘autres que filets’’ la formation d'un troisième corps oxydé. Ce dernier constitue un surplus de matière qui peut entrainer l'augmentation des contraintes mécaniques dans les assemblages. A l'interface ‘‘filets’’ écrou/vis, il a été constaté que si la mixture de troisièmes corps piégée en serrage n'est pas cohésive, elle est extrudée des contacts, initialisant la perte de la tension de serrage. A partir de ces interprétations, des interactions entre plusieurs circuits tribologiques conduisent à converger vers un scénario de fonctionnement des assemblages boulonnés, permettant de solutionner leurs défaillances par la re-conception (mise en place de gorge de décharge, ...)Since the use of bolts in the fifteenth century to assemble two parts, the bolted assemblies have the interrogations according to the understanding of their operating and failures occurring, such as the variation of the clamping force leading to, self-loosening, loss of sealing performance, cracks initialization, ... In order to understand their operating, a methodology focused on tribological approach was established, enabling to disassemble a bolted assembly without loosen its, allowing to not change the contact conditions during loosening. So, all the bolted assemblies interfaces (nut/screw ‘‘threads’’ and ‘‘others than threads’’) constituting tribological triplets, have been studied according to the three stages of their full life-cycle (manufacturing, tightening and service) using configurations of different materials. An interactive dialogue between the experiments (fields measuring by digital images correlation, tribological analysis) and the numerical simulation (Finite Element Method, Discrete Element Method) has led to interpretations about the three stages. During the manufacturing, the rolling of screws generates tribological superficial transformations in subsurfaces of machined threads. Contrariwise, inside the volume of these machined screws, there is no tribological transformation. So, this manufacturing process creates a difference of microstructure in these screws, that could be a source of their fatigue properties destruction. During the tightening, it produces at ‘‘threads’’ interface a ‘‘dry-solid’’ mixture of third bodies, accommodating the speed jump between the screw and the nut. This mixture is the result of a reactivity between a grease used for bolted tightening and the particles, detached by plastic flow from a coating initially applied on the threads of nuts and/or bolts. At the end of the process, a part of the mixture remains trapped in the threads, playing the role of maintaining the clamping force. In these conditions, it appears that the friction varies depending of the rheology of the mixture, conditioning the variation of the clamping force. In service, contact instabilities (slip, peeling off, ...) have been identified in the interfaces. These instabilities lead to the formation of an oxidized third body in ‘‘others than threads’’ interfaces. This oxidized third body represents a surplus of material and can increase mechanical stresses in the assemblies. In the nut/screw ‘‘threads’’ interface, it was found that if the mixture of third bodies trapped during the tightening stage is not cohesive, it is extruded, initializing the loss of clamping force. Based on the findings, the interactions between multiple tribological circuits lead to converge to a scenario of bolted assemblies operating, allowing to solve their failures by re-designing (create discharge grooves, ...)
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Korini, Thoma. "Modelisation tridimensionnelle par un assemblage de blocs rigides du comportement mecanique d'un massif rocheux a fissuration individualisee en vue de l'analyse de la stabilite d'ouvrages miniers." Paris, ENMP, 1988. http://www.theses.fr/1988ENMP0086.
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Developpement de deux methodes: stabilite d'un bloc isole avec la theorie de l'equilibre limite, prenant en compte l'effet de la contrainte horizontale; assemblage de blocs, prenant en compte leur action reciproque, par la theorie des blocs rigides: modele statique tridimensionnel, avec modelisation de la chute des blocs, de la dilatance et du soutenement par boulonnage
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Lopard, Gabriel. "Conception et dimensionnement des ouvrages souterrains dans les massifs rocheux discontinus – Développement de la méthode des blocs isolés." Electronic Thesis or Diss., Université Paris sciences et lettres, 2021. http://www.theses.fr/2021UPSLM014.
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De nombreux secteurs d’activités impliquent une occupation de l’espace souterrain. Le creusement dans un massif rocheux présente différents modes de ruine qu’il faut savoir identifier pour utiliser les outils de conception adaptés. Parmi eux, l’instabilité de blocs est un problème courant dans les massifs rocheux fracturés. Les approches numériques de blocs multiples permettent de considérer le massif dans son ensemble mais leur utilisation peut s’avérer lourde et requiert beaucoup de données d’entrée parfois indisponibles. L’approche Isobloc est basée sur le concept de bloc isolé et, comparée aux autres méthodes du même type, elle est plus rigoureuse dans la résolution du problème de mécanique du bloc. Dans cette thèse, cette méthode a été étudiée afin de pouvoir l’intégrer dans la démarche de conception en milieu rocheux fracturé. Une première partie s’intéresse spécifiquement à la loi de comportement normal des joints, et à la définition d’indicateurs afin de quantifier la sécurité de l’état d’équilibre du bloc. Une autre partie présente les réflexions et manières de modéliser une solution de soutènement avec Isobloc. Trois types sont proposées suivant le degré de connaissance du soutènement. Enfin une application de la méthode Isobloc dans la démarche d’étude de stabilité de blocs a été proposé à partir de données d’un site d’étude réelMany activity sectors involve occupation of underground space. Digging in a rockmass presents different modes of ruin that must be identified in order to use the appropriate design tools. Among them, block instability is a usual problem in fractured rock masses. Numerical approaches of multiple blocks allow to consider the complete rockmass but their use can be hard and requires a lot of input data sometimes unavailable. The Isobloc approach is based on the isolated block concept and, compared to other methods based on the same concept, it is more rigorous in solving the block mechanics problem. In this thesis, this method has been studied in order to integrate it in the design approach of fractured rock mass. A first part is specifically interested in the normal joint behavior law, and in definition of indicators to quantify the safety of the block's equilibrium state. A second part presents reflections and ways to model a support solution with Isobloc. Three types are proposed according to the knowledge degree of the support. Finally, an application of the Isobloc method in the blocks stability study approach has been proposed using data from a real study site
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Bailey, Lillian Amanda. "The Bolton Analysis revisited." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0005/MQ34333.pdf.
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Le, Van Cong. "Numerical analysis of the interaction between rockbolts and rock mass for coal mine drifts in Vietnam." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2009. http://nbn-resolving.de/urn:nbn:de:bsz:105-5323241.
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The thesis describes the application of anchors in mining and tunneling and gives an up-to-date overview about anchor types, design principles and the interaction mechanisms between anchors and rockmass. A constitutive model was developed, implemented and tested for the 2- and 3-dimensional numerical codes FLAC and FLAC3D to simulate non-linear anchor behaviour including unloading and reloading. The interaction between rockbolts and rockmass was studied in detail via numerical simulations for 5 Vietnamese coal mines. An extended version of the so-called c-Φ reduction method and a new introduced reinforcement factor were applied to quantify the effect of bolting. Mine specific and generalised relations were deduced to quantify the influence of anchor length and distance between anchors on the effect of bolting.
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Kulichová, Jana. "Letištní hala." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2015. http://www.nusl.cz/ntk/nusl-227583.
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The construction of the concourse is designed from steel.Construction was designed in 2 variants.The construction of the hall is radially curved in plan view with a circular sector on the longitudinal side.Roof structure consists of eight trusses at an axial distance of 9 m.Tracks are arched truss designed as a parallel.Trusses are designed to span 40m.Maximum ground clearance hall at the top is 14 meters.Letištní hala byla řešena v programu Scia Engineer 2014 a součástí je i výkresová dokumentace.
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Karel, Jaroslav. "Výrobna veterinárních léčiv Tekro – Nová Dědina - stavebně technologický projekt." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-227062.
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The content of this thesis is the construction technology project construction hall for the production of veterinary drugs Tekro in the village Nová Dedina. In this work addresses the project site equipment, scheduling, technical regulations, inspection and test plan, a study of the main technological stages of the building.
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Williams, John Alan. "Cricket and society in Bolton between the wars." Thesis, Lancaster University, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.333895.
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Wilkinson, Timothy James. "The Plastic Behaviour of Cold-Formed Rectangular Hollow Sections." University of Sydney. Department of Civil Engineering, 2000. http://hdl.handle.net/2123/843.
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The aim of this thesis is to assess the suitability of cold-formed rectangular hollow sections (RHS) for plastic design. The project involved an extensive range of tests on cold-formed Grade C350 and Grade C450 (DuraGal) RHS beams, joints and frames. A large number of finite element analyses was also carried out on models of RHS beams. The conclusion is that cold- formed RHS can be used in plastic design, but stricter element slenderness (b/t) limits and consideration of the connections, are required. Further research, particularly into the effect of axial compression on element slenderness limits, is required before changes to current design rules can be finalised. Bending tests were performed on cold-formed RHS to examine the web and flange slenderness required to maintain the plastic moment for a large enough rotation suitable for plastic design. The major conclusions of the beam tests were: (i) Some sections which are classified as Compact or Class 1 by current steel design specifications do not maintain plastic rotations considered sufficient for plastic design. (ii) The current design philosophy, in which flange and web slenderness limits are independent, is inappropriate. An interaction formula is required, and simple formulations are proposed for RHS. Connection tests were performed on various types of knee joints in RHS, suitable for the column - rafter connection in a portal frame. The connection types investigated were welded stiffened and unstiffened rigid knee connections, bolted plate knee joints, and welded and bolted internal sleeve knee joints, for use in RHS portal frames. The ability of the connections to act as plastic hinges in a portal frame was investigated. The most important finding of the joint tests was the unexpected fracture of the cold-formed welded connections under opening moment before significant plastic rotations occurred. The use of an internal sleeve moved the plastic hinge in the connection away from the connection centre- line thus eliminating the need for the weld between the RHS, or the RHS and the stiffening plate, to carry the majority of the load. The internal sleeve connections were capable of sustaining the plastic moment for large rotations considered suitable for plastic design. Tests on pinned-base portal frames were also performed. There were three separate tests, with two different ratios of vertical to horizontal point loads, simulating gravity and horizontal wind loads. Two grades of steel were used for comparison. The aims of the tests were to examine if a plastic collapse mechanism could form in a cold-formed RHS frame, and to investigate if plastic design was suitable for such frames. In each frame, two regions of highly concentrated curvature were observed before the onset of local buckling, which indicated the formation of plastic hinges and a plastic collapse mechanism. An advanced plastic zone structural analysis which accounted for second order effects, material non-linearity and member imperfections slightly overestimated the strength of the frames. The analysis slightly underestimated the deflections, and hence the magnitude of the second order effects. A second order plastic zone analysis, which did not account for the effects of structural imperfections, provided the best estimates of the strengths of the frames, but also underestimated the deflections. While cold-formed RHS did not satisfy the material ductility requirements specified for plastic design in some current steel design standards, plastic hinges and plastic collapse mechanisms formed. This suggests that the restriction on plastic design for cold-formed RHS based on insufficient material ductility is unnecessary, provided that the connections are suitable for plastic hinge formation, if required. A large number of finite element analyses were performed to simulate the bending tests summarised above, and to examine various parameters not studied in the experimental investigation. To simulate the experimental rotation capacity of the RHS beams, a sinusoidally varying longitudinal local imperfection was prescribed. The finite element analysis determined similar trends as observed experimentally, namely that the rotation capacity depended on both the web slenderness and flange slenderness, and that for a given section aspect ratio, the relationship between web slenderness and rotation capacity was non-linear. The main finding of the finite element study was that the size of the imperfections had an unexpectedly large influence on the rotation capacity. Larger imperfections were required in the more slender sections to simulate the experimental results. There should be further investigation into the effect of varying material properties on rotation capacity.
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Wilkinson, Timothy James. "The Plastic Behaviour of Cold-Formed Rectangular Hollow Sections." Thesis, The University of Sydney, 1999. http://hdl.handle.net/2123/843.
Full textAbstract:
The aim of this thesis is to assess the suitability of cold-formed rectangular hollow sections (RHS) for plastic design. The project involved an extensive range of tests on cold-formed Grade C350 and Grade C450 (DuraGal) RHS beams, joints and frames. A large number of finite element analyses was also carried out on models of RHS beams. The conclusion is that cold- formed RHS can be used in plastic design, but stricter element slenderness (b/t) limits and consideration of the connections, are required. Further research, particularly into the effect of axial compression on element slenderness limits, is required before changes to current design rules can be finalised. Bending tests were performed on cold-formed RHS to examine the web and flange slenderness required to maintain the plastic moment for a large enough rotation suitable for plastic design. The major conclusions of the beam tests were: (i) Some sections which are classified as Compact or Class 1 by current steel design specifications do not maintain plastic rotations considered sufficient for plastic design. (ii) The current design philosophy, in which flange and web slenderness limits are independent, is inappropriate. An interaction formula is required, and simple formulations are proposed for RHS. Connection tests were performed on various types of knee joints in RHS, suitable for the column - rafter connection in a portal frame. The connection types investigated were welded stiffened and unstiffened rigid knee connections, bolted plate knee joints, and welded and bolted internal sleeve knee joints, for use in RHS portal frames. The ability of the connections to act as plastic hinges in a portal frame was investigated. The most important finding of the joint tests was the unexpected fracture of the cold-formed welded connections under opening moment before significant plastic rotations occurred. The use of an internal sleeve moved the plastic hinge in the connection away from the connection centre- line thus eliminating the need for the weld between the RHS, or the RHS and the stiffening plate, to carry the majority of the load. The internal sleeve connections were capable of sustaining the plastic moment for large rotations considered suitable for plastic design. Tests on pinned-base portal frames were also performed. There were three separate tests, with two different ratios of vertical to horizontal point loads, simulating gravity and horizontal wind loads. Two grades of steel were used for comparison. The aims of the tests were to examine if a plastic collapse mechanism could form in a cold-formed RHS frame, and to investigate if plastic design was suitable for such frames. In each frame, two regions of highly concentrated curvature were observed before the onset of local buckling, which indicated the formation of plastic hinges and a plastic collapse mechanism. An advanced plastic zone structural analysis which accounted for second order effects, material non-linearity and member imperfections slightly overestimated the strength of the frames. The analysis slightly underestimated the deflections, and hence the magnitude of the second order effects. A second order plastic zone analysis, which did not account for the effects of structural imperfections, provided the best estimates of the strengths of the frames, but also underestimated the deflections. While cold-formed RHS did not satisfy the material ductility requirements specified for plastic design in some current steel design standards, plastic hinges and plastic collapse mechanisms formed. This suggests that the restriction on plastic design for cold-formed RHS based on insufficient material ductility is unnecessary, provided that the connections are suitable for plastic hinge formation, if required. A large number of finite element analyses were performed to simulate the bending tests summarised above, and to examine various parameters not studied in the experimental investigation. To simulate the experimental rotation capacity of the RHS beams, a sinusoidally varying longitudinal local imperfection was prescribed. The finite element analysis determined similar trends as observed experimentally, namely that the rotation capacity depended on both the web slenderness and flange slenderness, and that for a given section aspect ratio, the relationship between web slenderness and rotation capacity was non-linear. The main finding of the finite element study was that the size of the imperfections had an unexpectedly large influence on the rotation capacity. Larger imperfections were required in the more slender sections to simulate the experimental results. There should be further investigation into the effect of varying material properties on rotation capacity.
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Cerejeira, João Paulo Rebelo Gonçalves. "Aplicação dos oclusogramas no diagnóstico das discrepâncias de Bolton." Master's thesis, Universidade do Porto. Reitoria, 2004. http://hdl.handle.net/10216/9633.
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Hahlo, Kenneth Geoffrey. "The Gujaratis of Bolton : the leaders and the led." Thesis, Open University, 1993. http://oro.open.ac.uk/57417/.
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This thesis is a study of local rather than national black politics. The participation of Gujaratis, who comprise the largest ethnic minority community in Bolton, in local politics is constrained by their loyalty to Gujarati identities and by racism within political parties. The settlement patterns of Gujaratis in Bolton reflect in part the socio-economic constraints experienced by black immigrants in Britain generally, and in part their allegiance to faction, caste, sect and religious identities. On the basis of some of these social identities have developed organisations which respond to particular social, religious and political needs. These organisations provide the only opportunities for the development of black structures of support and leadership within this large community. Notions of racism are based upon a dialogue between white and Gujarati notions of what is common sense. These notions form the basis of Gujaratis' perceptions of social distances that separate them from others. The core of support for leaders is based upon personal social networks. The social characteristics of these social networks influence the patterns of close friendships between Gujaratis and members of other communities in the town. These patterns show that Gujaratis exclude Gujaratis who belong to other Gujarati religious communities and members of other ethnic communities, black and white, from close friendships. Friendships with those perceived to be social distant are of lower intensity, thus excluding these people from sharing in a common body of Gujarati knowledge. In the context of Bolton these Gujaratis find themselves unable to participate within the formal political hierarchy and decision making arenas. The local Community Relations Council offers Gujarati and other black leaders of organisations a forum within which they can meet with some of the locally and nationally elected political representatives. The debate centres on events, involving Gujarati and other participants, which allow leaders of Gujarati organisations and politicians and other members of the CRC to negotiate the power relations between black and white. However, the consequence is that the Gujaratis are still relegated to the periphery of formal political decision-making arenas.
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Cerejeira, João Paulo Rebelo Gonçalves. "Aplicação dos oclusogramas no diagnóstico das discrepâncias de Bolton." Dissertação, Universidade do Porto. Reitoria, 2004. http://hdl.handle.net/10216/9633.
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Taylor, Peter Forbes. "Popular politics and labour-capital relations in Bolton, 1825-1850." Thesis, Lancaster University, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.315543.
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Janin, Jean-Pierre. "Tunnels en milieu urbain : Prévisions des tassements avec prise en compte des effets des pré-soutènements (renforcement du front de taille et voûte-parapluie)." Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00743362.
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Dans les années 80, de nouvelles techniques, basées sur la mise en place de système de présoutènements à l'avant du front de taille, se sont développées dans le domaine du creusement de tunnels dans des terrains difficiles. Ce travail de thèse représente une contribution à l'étude des effets de deux types de présoutènements mis en œuvre, le boulonnage au front et la voûte parapluie, sur les déformations du massif et sur la valeur du taux de déconfinement. L'objectif étant d'améliorer les méthodes de prévision des tassements en surface pour les tunnels réalisés avec des techniques de présoutènements. Pour atteindre ce but, l'étude s'est basée sur deux étapes principales : dans un premier temps, une participation active au suivi régulier des déformations enregistrées sur le chantier du tube sud de Toulon ; dans un deuxième temps, l'élaboration d'analyses en retour à l'aide de modélisations numériques calées sur les observations collectées sur le chantier. Le suivi des déformations du massif et la mise en place de deux sections ins-trumentées ont permis d'acquérir une importante base de données sur laquelle les simulations numériques ont été validées. Les mesures enregistrées in situ ont mis en évidence que le champ de déformation provoqué par le creusement du tunnel est tridimensionnel. L'analyse de l'évolution des mouvements en surface a également conduit à proposer une expression analytique de prévision des tassements de surface, qui a été ensuite utilisée pour le pilotage du creusement du tunnel. Des analyses en retour, basées sur les mesures enregistrées in situ, ont été réalisées avec des simulations numériques bidimensionnelles et tridimensionnelles. L'approche 2D a souligné la forte influence du choix de la valeur du taux de déconfinement sur les résultats numériques. Afin de lever cette incertitude, un modèle 3D a été mis au point et a permis d'étudier l'influence des différents systèmes de (pré)soutènements sur la réaction du massif encaissant. Le boulonnage au front de taille et la distance de retard du contreradier ont montré avoir un rôle prépondérant sur le développement des mouvements dans le massif. Des calculs bidimensionnels ont été effectués en parallèle et les résultats ont été calés sur ceux du calcul 3D afin de trouver le taux de déconfinement correspondant à chaque configuration de (pré)soutènement testée. Les deux approches numériques, 2D et 3D, ont enfin été calées sur une section du tunnel de Toulon et la correspondance très satisfaisante avec les mesures in situ a permis de valider nos simulations. Une réflexion finale sur les résultats obtenus semble montrer que le taux de décon-finement est beaucoup plus influencé par le phasage des travaux et le présoutènement, que par les caractéristiques géomécaniques intrinsèques du massif.
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Boltena, Abiot Sinamo [Verfasser]. "Neuro-Fuzzy-ANP-based Decision Model for ERP System Selection / Abiot Sinamo Boltena." Aachen : Shaker, 2014. http://d-nb.info/1058315471/34.
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Bolten, Dennis [Verfasser]. "Erzeugung und Abscheidung submikroner Wirkstoffpartikel mittels Entspannung überkritischer Lösungen / Dennis Bolten." München : Verlag Dr. Hut, 2011. http://d-nb.info/1018982825/34.
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Bolten, Kristina [Verfasser]. "Nabelschnurumschlingungen um den Hals des Feten : Risiko, Diagnostik, Informationsbedarf / Kristina Bolten." Berlin : Medizinische Fakultät Charité - Universitätsmedizin Berlin, 2012. http://d-nb.info/1028494599/34.
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Holding, David. "Conflict and assimilation : Irish communities in Bolton and Preston 1840-1914." Thesis, Manchester Metropolitan University, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249738.
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Wang, Fukang. "Real time instruction generator for the Bolton urban drainage control system." Thesis, University of Salford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.245021.
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Vale, Brigette. "The Scropes of Bolton and of Masham, c.1300-c.1450 : a study of a northern noble family with a calendar of the Scrope of Bolton Cartulary." Thesis, University of York, 1987. http://etheses.whiterose.ac.uk/4271/.
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Krocker, Carsten. "Contribution à l'étude des mécanismes de plastification autour d'une barre d'ancrage scellée dans le rocher." Phd thesis, Université Joseph Fourier (Grenoble), 1996. http://tel.archives-ouvertes.fr/tel-00785863.
Full textAbstract:
Une modélisation du comportement d'un ancrage passif est proposé prenant en compte les trois matériaux. acier, scellement et roche, et leurs comportements spéciflques. Le comportement d'un forage cimenté soumis à une pression intérieure est étudié en deux dimensions. Les relations entre la pressIon appliquée sur le scellmnent et le déplacement correspondant sont établies pour les différents états du scellement et de la roche (élasticité, fracturé, plastique). Une simulation numèrique permet. de comparer les comportements successifs d'un forage cimenté, lorsqu'il est soumis à un chargement intérieur axisymétrique puis à un chargement uniaxial, qui se rapproche de celui exercé par une barre soumise à un déplacement transversal. La relation analytique entre pression et déplacement est appliquée à la modélisation tridimensionneile d'un ancrage soumis àun cisaillement au niveau d'un joint. Une méthode basée sur une décomposition de la barre en tranches et en éléments est proposée pour des petites déformations. Elle permet de calculer les efforts mobilisès dans la barre et sa déformation, en fonction du déplacement imposé au joint.
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Moore, Emma Frances. "Learning style and identity: a sociolinguistic analysis of a Bolton high school." Thesis, University of Manchester, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488050.
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Bolten, Jens [Verfasser]. "Entwurf und Optimierung Elektronenstrahllithographie–basierter Herstellungsprozesse für die anwendungsorientierte Nanotechnologie / Jens Bolten." München : Verlag Dr. Hut, 2013. http://d-nb.info/103634570X/34.
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Doherty, J. C. "Short-distance migration in Mid-Victorian Lancashire : Blackburn and Bolton 1851-71." Thesis, Lancaster University, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372536.
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