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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.
291

Eram realmente pitag?rico(a)s os homens e mulheres catalogado(a)s por J?mblico em sua obra Vida de Pit?goras?

Silva, Josildo Jose Barbosa da 25 October 2010 (has links)
Made available in DSpace on 2014-12-17T14:36:18Z (GMT). No. of bitstreams: 1 JosildoJBS_TESE.pdf: 1777094 bytes, checksum: a9a39551fbb840b0d01e7dbe25e6122d (MD5) Previous issue date: 2010-10-25 / Pythagoras was one of the most important pre-Socratic thinkers, and the movement he founded, Pythagoreanism, influenced a whole thought later in religion and science. Iamblichus, an important Neoplatonic and Neopythagorean philosopher of the third century AD, produced one of the most important biographies of Pythagoras in his work Life of Pythagoras. In it he portrays the life of Pythagoras and provides information on Pythagoreanism, such as the Pythagorean religious community which resembled the cult of mysteries; the Pythagorean involvement in political affairs and in the government in southern Italy, the use of music by the Pythagoreans (means of purification of healing, use of theoretical study), the Pythagorean ethic (Pythagorean friendship and loyalty, temperance, self-control, inner balance); justice; and the attack on the Pythagoreans. Also in this biography, Iamblichus, almost seven hundred years after the termination of the Pythagorean School, established a catalog list with the names of two hundred and eighteen men and sixteen women, supposedly Pythagoreans of different nationalities. Based on this biography, a question was raised: to what extent and in what ways, can the Pythagoreans quoted by Iamblichus really be classified as Pythagoreans? We will take as guiding elements to search for answers to our central problem the following general objectives: to identify, whenever possible, which of the men and women listed in the Iamblichus catalog may be deemed Pythagorean and specific; (a) to describe the mystery religions; (b) to reflect on the similarities between the cult of mysteries and the Pythagorean School; (c) to develop criteria to define what is being a Pythagorean; (d) to define a Pythagorean; (e) to identify, if possible, through names, places of birth, life, thoughts, work, lifestyle, generation, etc.., each of the men and women listed by Iamblichus; (f) to highlight who, in the catalog, could really be considered Pythagorean, or adjusting to one or more criteria established in c, or also to the provisions of item d. To realize these goals, we conducted a literature review based on ancient sources that discuss the Pythagoreanism, especially Iamblichus (1986), Plato (2000), Aristotle (2009), as well as modern scholars of the Pythagorean movement, Cameron (1938), Burnet (1955), Burkert (1972), Barnes (1997), Gorman (n.d.), Guthrie (1988), Khan (1999), Matt?i (2000), Kirk, Raven and Shofield (2005), Fossa and Gorman (n.d.) (2010). The results of our survey show that, despite little or no availability of information on the names of alleged Pythagoreans listed by Iamblichus, if we apply the criteria and the definition set by us of what comes to be a Pythagorean to some names for which we have evidence, it is possible to assume that Iamblichus produced a list which included some Pythagoreans / Pit?goras ? considerado um dos mais importantes pensadores pr?-socr?ticos. A escola pitag?rica, por ele fundada, influenciou todo um pensar posterior na religi?o e na ci?ncia. J?mblico, fil?sofo neoplat?nico e neopitag?rico do s?culo III d.C., elaborou, quase setecentos anos ap?s o t?rmino do movimento pitag?rico, uma das tr?s biografias de Pit?goras, a Vida de Pit?goras. Nela, ele retrata a vida desse fil?sofo e nos fornece informa??es sobre o pitagorismo: uma comunidade religiosa assemelhada ao culto de mist?rios; o envolvimento de seus participantes em assuntos pol?ticos e no governo no sul da It?lia; a exalta??o dada ? m?sica (meio de purifica??o, de cura, recurso de estudo te?rico), ? ?tica (amizade, lealdade, temperan?a, autocontrole, equil?brio interior), ? justi?a, e o ataque sofrido pelos pitag?ricos. Ao final dessa biografia, J?mblico elabora um cat?logo com os nomes de duzentos e dezoito homens e dezesseis mulheres, suposto(a)s pitag?rico(a)s de diversas nacionalidades. Tomando como base essa biografia, lan?a-se a quest?o: at? que ponto, e em quais aspectos, esses homens e mulheres citado(a)s por J?mblico podem realmente ser classificados como pitag?rico(a)s? Tomaremos como elementos norteadores ? busca de respostas para nosso problema central os seguintes objetivos (i) geral, identificar, quando poss?vel, quais dos homens e mulheres listados no cat?logo de J?mblico podem ser considerados pitag?ricos, e (ii) espec?ficos: (a) caracterizar as religi?es de mist?rios; (b) refletir sobre as semelhan?as entre o culto de mist?rios e a escola pitag?rica; (c) desenvolver crit?rios que v?o definir o que ? ser um pitag?rico; (d) definir um pitag?rico; (e) identificar, se poss?vel, atrav?s dos nomes, locais de nascimento, vidas, pensamentos, obras, estilo de vida, gera??o, etc., cada um dos homens e mulheres listados por J?mblico; (f) destacar, no cat?logo, quem realmente poderia ser considerado um(a) pitag?rico (a), ou se adequando a um ou v?rios crit?rios estabelecidos em c, ou atendendo ao disposto no item d. Para dar conta de tais objetivos, realizamos uma pesquisa bibliogr?fica valendo-se de fontes antigas que discutem o pitagorismo, principalmente J?mblico (1986), Plat?o (2000/s.d.), Arist?teles (s.d.), e modernos estudiosos desse movimento: Cameron (1938), Burnet (1955), Burkert (1972), Guthrie (1988/2003), Barnes (1997), Khan (1999), Gorman (1979), Matt?i (2000), Kirk, Raven & Shofield (2005), e Fossa (2006/2010). Os resultados de nossa pesquisa mostram que, se utilizarmos as raras informa??es acerca de poucos desse(a)s suposto(a)s homens e mulheres catalogado(a)s por J?mblico, e se aplicarmos sobre eles os crit?rios e a defini??o por n?s anteriormente estabelecidos sobre o que vem a ser um pitag?rico, ? poss?vel supor que a lista elaborada por J?mblico pode estar constitu?da por alguns homens e mulheres que possu?am um modo de vida e um interesse por determinados assuntos caracteristicamente pitag?ricos
292

Estudo hist?rico e pedag?gico sobre ternos pitag?ricos ? luz de Eug?ne Bahier

Silva, Georgiane Amorim 14 December 2010 (has links)
Made available in DSpace on 2014-12-17T15:04:52Z (GMT). No. of bitstreams: 1 GeorgianeAS.pdf: 3018319 bytes, checksum: fe1da0a81a6bfdd332127f5ebc8367e1 (MD5) Previous issue date: 2010-12-14 / At the present investigation had the purpose to achieve a descritive analysis pedagogy in the work of Recherche m?thodique et propri?t?s des triangles rectangles en nombres entiers. According to the analysis achieved, we made and applyed the teaching module called Pitagories: one of tools to comprehension Pitagory Theorema, there were studying by public students in mathematic course in the UFRN , the new mathematic teachers in future. The analysis the was made with writen test the was showed that all students got the view comprehension in the teaching approach module, to apointed the difference in the learning qualytative with other reseach that was made with quastionaire and enterview. With this module that was made with the new future teacheres there was more attention the better comprehension with the Pitagory Theorema, that was good focus in the pitagory about the potential historical pedagogyc in the work studied. / O presente trabalho apresenta uma an?lise descritiva, hist?rica e pedag?gica da obra Recherche m?thodique et propri?t?s des triangles rectangles en nombres entiers. De acordo com a an?lise realizada, elaboramos e aplicamos o m?dulo de ensino intitulado Ternos Pitag?ricos: uma ferramenta para compreens?o do Teorema de Pit?goras, tendo como p?blico alvo os alunos do curso de Licenciatura em Matem?tica, da UFRN, futuros professores de Matem?tica. A an?lise dos dados coletados da prova escrita, de modo geral mostrou que os alunos assimilaram com relativa compreens?o os conceitos abordados no m?dulo de ensino, apontando para uma diferen?a qualitativa na aprendizagem com rela??o aos dados obtidos nos primeiros instrumentos utilizados, a saber: question?rio e entrevista. Com o m?dulo de ensino realizado, proporcionamos aos futuros professores, uma maior compreens?o do Teorema de Pit?goras, tendo como enfoque os Ternos Pitag?ricos sob uma apresenta??o hist?rica, constantando o potencial pedag?gico da obra em foco.
293

VLIV LAND USE NA VYTĚŽENÉ PÍSKOVNY V OBLASTI VESELÍ NAD LUŽNICÍ / Impact of land use on the former sand-pits in the region of Veselí nad Lužnicí

NOVÁK, Ondřej January 2009 (has links)
Sand-pits which were formed especially in the floodplain of the Lužnice River since the 1950s currently constitute important landscape element of the Třeboň Basin. My diploma thesis is focused on the assessment of the impact of land use on the former sand-pits in the region of Veselí nad Lužnicí. Field investigations were carried out from the beginning of June till the end of August 2008. I mapped the land use of this area by using a map key. I put down particular areas {--} agricultural areas, forest areas, water areas, bild-up areas, other areas {--} into map photographs. The total area of the mapped territory was 989 hecteres. The biggest part of the area comprises of forest growths and field-grown plants. Water areas (with the main element of the mapped area {--} a system of former sandpits) formed 23% of the total area. On the bank sof the sand-pits were placed phytosociological relevé, which illustrated littoral vegetation and environment in which this vegetation is located, and what is the influence of human activity on vegetation. I placed 74 phytosociological relevé in this system. I recorded 125 plant species {--} out of these were 104 herb plants and 21 woody species. I recorded 41 nitrophilous, 52 wetland, 16 ruderal and 2 stronngly endangered species. Altogether, 20 water samplings were carried out. Horusice I sand-pit is the richest in nutrient, the poorest in nutrients is Horusice sand-pit.
294

Selamento de fossas e fissuras após 6 meses com diferentes materiais: Resinoso X Ionómerico / Pit and fissure sealants with different materials: Resin Based X Glass Ionomer Cement Results after six months

Priscilla Santana Pinto Gonçalves 24 May 2013 (has links)
Este estudo avaliou e comparou, após 6 meses, dois materiais usados como selantes de fossas e fissuras, FluroShield® (Dentsply, Germany) e Clinpro™ XT Varnish (3M ESPE, Dental Products, St. Paul, MN, U.S.A.) quanto à retenção e características superficiais. Além disso, comparou-os, com um grupo controle não selado, com relação à incidência de cárie no período. Participaram deste trabalho, 31 crianças de 6 a 8 anos de idade, com no mínimo dois primeiros molares permanentes hígidos e história de cárie, num total de 114 dentes divididos aleatoriamente em três grupos: CLP (Clinpro™ XT Varnish), FS (FluroShield®) e ctr (Controle). O selamento foi realizado sob isolamento relativo para ambos os materiais testados, após profilaxia prévia com jato de bicarbonato de sódio e água e, condicionamento com gel de ácido fosfórico a 35% por 15 segundos. A avaliação clínica foi realizada por dois examinadores calibrados após 6 meses. Avaliou-se a retenção e a incidência de cárie nas cinco áreas oclusais: OM, OC, OD, OV e OL; e as características superficiais e a retenção considerando a superfície oclusal como um todo. Houve diferença estatisticamente significante para a prevalência de cárie (teste de Kruskal Wallis, p=0,000 a 0,007), para todas as áreas, entre os grupos selados (CLP e FS) e o controle. Sendo que quanto à incidência, só foi verificada diferença significante para a área OL (p=0,014). O teste do Qui-quadrado identificou que não houve diferença estatisticamente significante entre os materiais, com relação à taxa de sucesso de retenção da superfície oclusal como um todo, quando se considerou o somatório das cinco áreas (p=0,079) ou quando se verificou a retenção por superfície (p=0,141). No entanto, a análise do conjunto de critérios de retenção na superfície oclusal toda, mostrou uma diferença estatisticamente significante para o FS (teste de Mann-Whitney, p=0,002). Em relação às características superficiais, o FS apresentou superioridade durante o período estudado de forma significativa, indicada pelo teste de Mann-Whitney, para a deterioração marginal (p=0,000), descoloração marginal (p=0,008), e descoloração superficial (p=0,001). Ele também foi superior, mas não significante, quanto à textura superficial. A frequência de bolhas nas superfícies seladas não mostrou diferença significativa (teste do Qui-quadrado, p=0,758) entre os materiais. Desta forma, pode-se concluir que ambos os materiais foram efetivos nos primeiros 6 meses de avaliação, embora, tenha havido melhor desempenho clínico do selante FluroShield®. / This study evaluated and compared two dental sealants, for 6 months. The materials, Fluroshield® (Dentsply, Germany) and Clinpro™ XT Varnish (3M ESPE Dental Products, St. Paul, MN, USA) were analyzed with regard their retention and superficial characteristics. They also were compared with a control group, without sealant, regarding the dental caries incidence. The sample was composed by 31 children from 6 to 8 years of age, with at least two sound first permanent molars, but with a dental caries history. A total of 114 teeth were randomly alocated in three groups: CLP (Clinpro™ XT Varnish), FS (Fluroshield®) and ctr (Control). The sealings were applyed under relative isolation after a previous prophylaxis with a water-air-polishing jet, and an enamel etching with a 35% phosphoric acid gel for 15 seconds. Clinical evaluation was performed by two calibrated examiners after 6 months considering: the sealant retention and the incidence of occlusal caries in five areas: OM, OC, OD, OV and OL and finally, the surface characteristics and retention considering the occlusal surface as only one area. It was shown a significant difference (Kruskal-Wallis test, p=0.000 to 0.007) for the caries prevalence in all areas comparing the sealed group (CLP and FS) versus control. Whereas the incidence, it was only verified a significant diference for the OL area (p=0.014). There was no significant difference (Chi-square test, p=0.079) between the materials regarding the success rate of retention for the occlusal surface when it was considered the sum of the five areas, or for the occlusal surface without divisions (p=0.141). Nevertheless there was a significant difference between the sealants (Mann-Whitney test, p=0.002), with better results for the FS group, when it was analysed the influence of all the retention criteria. Regarding the surface characteristics, the FS group showed a significant superiority (Mann-Whitney test) during the period of the study for the impairment marginal (p=0.000), marginal discoloration (p=0.008), and surface discoloration (p=0.001). Although FS had also been superior for the surface texture, this result was not significant. The frequency of bubbles in the sealed surfaces was not significant (Qui-square test, p=0.758) between the materials. Thus, it can be concluded that both materials were effective during this first 6 months of evaluation, although it is evident that the Fluroshield® sealant had shown a better clinical performance.
295

Efeitos de um cimento de ionômero de vidro e de um selante resinoso em esmalte bovino desmineralizado, submetido ou não a desafio cariogênico - estudo ‘in situ’ / Effects of a glass ionomer cement and a resin sealant on bovine demineralized enamel, submitted or not to a cariogenic challenge - in situ study

Adriano Tomio Hoshi 12 September 2006 (has links)
Este estudo in situ avaliou em esmalte bovino desmineralizado, submetido ou não a um desafio cariogênico, os efeitos de um cimento de ionômero de vidro de alta viscosidade (CIVav) e de um selante resinoso, comparativamente a um controle (sem selamento). Doze voluntários usaram dispositivos intrabucais palatinos (DIP) contendo 12 blocos de esmalte bovino desmineralizado, fixados dois a dois para simular uma fissura em V, a qual foi selada com um dos materiais: CIVav (Ketac, Molar Easymix), selante resinoso (Delton) ou controle (sem selamento). Metade dos espécimes foi submetida ao acúmulo de biofilme, recebendo oito aplicações diárias de sacarose a 20% para provocar um desafio cariogênico, além de outras três, de solução de dentifrício fluoretado (1 g : 3 mL), enquanto a outra metade não sofreu acúmulo de biofilme, mas também recebeu o dentifrício. Após 14 dias, foram avaliadas as concentrações de flúor no biofilme e no esmalte, bem como o conteúdo mineral (microdureza em secção longitudinal). Os dados obtidos foram analisados estatisticamente ('alfa'= 5%). O teste Friedman ANOVA revelou que a concentração de flúor no biofilme foi estatisticamente maior com o uso do CIVav, em comparação ao selante resinoso e ao controle. A ANOVA e o teste de Tukey constataram que houve maior concentração de flúor no esmalte associado ao CIVav, sobretudo na ausência de desafio cariogênico, enquanto o selante resinoso e controle foram semelhantes. Em relação ao conteúdo mineral, a ANOVA e o teste de Tukey detectaram diferenças entre os grupos na camada mais superficial do esmalte. Com desafio cariogênico, o conteúdo mineral foi sempre maior no esmalte associado ao CIVav do que naquele associado ao selante resinoso, sendo que o controle apresentou resultados intermediários. Sem o desafio cariogênico, houve uma tendência de um maior conteúdo mineral no grupo controle. Os resultados sugerem que o CIVav, aplicado sobre uma superfície desmineralizada e sob desafio cariogênico, demonstrou um potencial cariostático pela sua capacidade de doar flúor à estrutura e ao biofilme dentários, minimizando os efeitos da desmineralização, mas não melhorou a remineralização. / This in situ study evaluated on demineralized bovine enamel, submitted or not to a cariogenic challenge (dental biofilm), the effects of a high viscosity glass ionomer cement (HV-GIC) and a resin sealant in comparison with a control group (without sealing). Twelve volunteers wore a palatal appliance containing 12 blocks of demineralized bovine enamel mounted (2 by 2) to simulate a fissure in a V shape and sealed with: HV-GIC (Ketac? Molar Easymix), resin sealant (Delton) or maintained with no sealing material (control). Half of specimens was submitted to a cariogenic challenge by dripping a 20% sucrose solution 8 times/day besides a fluoride dentifrice solution (1 g : 3 mL) 3 times/day. The others specimens only received a dentifrice solution. After 14 days, the concentration of fluoride in dental biofilm and enamel was evaluated as well as the mineral content (cross-sectional microhardness) of the enamel. The concentration of fluoride in dental biofilm was higher with HV-GIC (Friedman ANOVA, p<0.05) in comparison with resin sealant and control group. The concentration of loosely-bound fluoride on enamel was significant (ANOVA and Tukey test, p< 0.05) specially without a cariogenic challenge for HVGIC, while it was similar for the resin sealant and control group. Concerning the mineral content, ANOVA and Tukey test (p<0.05) detected differences among the groups on the superficial layers of the enamel. Under the dental biofilm influence the mineral content was always higher on the enamel associated with HV-GIC than with resin sealant and the control group presented intermediary results. Without dental biofilm the control group presented a tendency of a higher mineral content. The results suggest that HV-GIC applied on a demineralized surface and under the dental biofilm influence has shown a cariostatic potential by its ability to give fluoride to the dental structure and biofilm reducing the demineralization effects.
296

Avaliação de dois cimentos de ionômero de vidro comparados a um selante resinoso, utilizados para selamento de fossas e fisuras aplicados em esmalte bovino hígido, sob condições de severo desafio cariogênico: estudo in situ / Evaluation of two glass ionomer cements compared to a resin sealant, employed for pit and fissure sealing on intact bovine enamel, under severe cariogenic challenge - in situ study

Vivian de Agostino Biella 02 March 2007 (has links)
Este estudo in situ, desenvolvido em uma fase de 14 dias, teve como objetivo avaliar o efeito de dois cimentos de ionômero de vidro (CIV) comparados a um selante resinoso, utilizados para selamento de fossas e fissuras aplicados em esmalte bovino hígido, com acúmulo de biofilme dentário, por meio da análise do conteúdo de flúor do biofilme dentário e da microdureza em secção longitudinal. Foram utilizados 88 blocos de esmalte (4mm x 4mm) de incisivos bovinos, selecionados por seu valor de microdureza inicial. Os blocos formaram uma fissura artificial em forma de \"V\" a qual foi selada, para compor os seguintes grupos: GI-CIVav (Ketac? Molar Easymix); GII-CIV modificado por resina (Vitremer?); GIII-selante resinoso sem flúor (Helioseal® Clear) ou GIV-controle, sem selamento. As fissuras artificiais foram fixadas em um dispositivo intrabucal palatino (DIP), em duas fileiras distintas que foram cobertas por uma tela plástica para favorecer o acúmulo de biofilme dentário. Onze voluntários utilizaram o DIP 24 h/dia; gotejaram 8x/dia, uma solução de sacarose a 20% e, uma solução de dentifrício fluoretado (3ml de água deionizada : 1g de dentifrício fluoretado) sobre todas as fissuras 3x/dia. Após o período experimental, coletou-se o biofilme acumulado para a avaliação do conteúdo de flúor. As fissuras foram seccionadas ao meio para a avaliação da microdureza em secção longitudinal a partir da superfície do esmalte, em 4 profundidades (10, 30, 50, 70 µm). O limite esmalte/material da região oclusal era a posição zero (borda do material) e, a partir deste, realizadas seqüências de impressões a 50, 150 e 500 µm interna e externamente à borda do material. Os dados obtidos foram analisados estatisticamente (a= 5%). O teste de Friedman revelou que a concentração de flúor no biofilme não foi estatisticamente significante entre os grupos, (p<0,07), com uma tendência de melhores resultados para o CIVav. Quanto ao conteúdo mineral, a ANOVA e o teste de Tukey detectaram significância (p<0,05) para todos os grupos individualmente, na camada mais superficial do esmalte (10 µm). Nesta profundidade, não houve diferença entre os grupos. Essas comparações foram válidas para a maioria das distâncias analisadas. / This in situ study, developed in a 14-day period, aimed to evaluate the effect of two glass ionomer cements (GIC) compared to a resin sealant, employed for pit and fissure sealing on intact bovine enamel, with accumulation of dental biofilm, by analysis of the fluoride content on the dental biofilm and longitudinal microhardness. Eighty-eight enamel blocks (4mm x 4mm) of bovine incisors were employed, selected according to their initial microhardness value. The blocks formed a V-shaped artificial fissure that was sealed, constituting the following groups: GI - high-viscosity conventional GIC (Ketac? Molar Easymix); GII - resin-modified GIC (Vitremer?); GIII - resin sealant without fluoride (Helioseal? Clear); and GIV - control, without sealing. The artificial fissures were fixated on a palatal plate (PP), in two distinct rows, which were covered with a plastic screen to favor the accumulation of dental biofilm. Eleven volunteers employed the PP for 24h/day, dripped a 20% sucrose solution 8 times a day, and used a fluoridated dentifrice solution (3ml of deionized water : 1g of fluoridated dentifrice) on all fissures 3 times a day. After the study period, the accumulated biofilm was collected for evaluation of the fluoride content. The fissures were sectioned through the middle for evaluation of longitudinal microhardness from the enamel surface, at 4 depths (10, 30, 50, 70 µm). The enamel/material limit at the occlusal region was the zero position (material margin); from this point, indents were sequentially performed at 50, 150 and 500 µm internally and externally to the material margin. Data were statistically analyzed (a = 5%). The Friedman test revealed that the fluoride concentration in the biofilm was not statistically significantly different among groups (p<0.07), yet there was a tendency of better outcomes for the high-viscosity conventional GIC. With regard to the mineral content, the ANOVA and Tukey test revealed significance (p<0.05) for all groups individually, at the most superficial enamel layer (10 µm). At this depth, there was no difference among groups. These comparisons were valid for most distances analyzed..
297

Mecanismos de ruptura em taludes altos de mineração a céu aberto / Failure mechanisms in high rock slopes at open pit mining

Rolando Enrique Zea Huallanca 14 December 2004 (has links)
Na última década, muitas minas a céu aberto têm alcançado alturas de 600 metros ou mais, algumas com perspectiva em projeto de alcançar mais de 1100 m. A literatura especializada revela que os mecanismos de ruptura para taludes altos ainda não são bem entendidos. Existem dúvidas tanto em relação aos mecanismos de ruptura, como quanto à estimativa da resistência do maciço rochoso em tal escala. Recentemente, há uma tendência crescente da aplicação de análises numéricas para estudar a estabilidade de taludes altos, mas ainda não se consegue reproduzir todos os fenômenos envolvidos. Análises reportadas na literatura consideram apenas a configuração final da cava, sem levar em conta o processo evolutivo da escavação, e o dano induzido ao maciço decorrente deste processo. Este trabalho analisa este efeito e suas conseqüências na avaliação da segurança. Realizaram-se análises bidimensionais de tensão-deformação em taludes de rocha. Tais análises foram realizadas com modelos elástico linear e elasto plástico de amolecimento da coesão e de endurecimento do atrito, considerando a mobilização não simultânea das componentes de resistência no critério de Mohr-Coulomb, e a danificação do maciço rochoso. Avaliação preliminar da segurança de um talude hipotético mostrou que estas considerações são muito importantes. Foram considerados a altura do talude, o ângulo do talude e as tensões in situ. 0 histórico de tensões modifica os parâmetros de resistência do maciço ao longo do talude por danificação. A região do pé do talude, em cada estágio de escavação, está sujeita a concentração de tensões induzidas que geram danificação ao maciço nestas áreas. A danificação em regiões do pé do talude pode explicar o inicio do processo de rupturas do tipo progressivo. / Along the last decade, many open pit mines have reached up to 600 meters or more in height, and some of them are planned to reach more than 1100 meters. The specialized literature shows that the failure mechanisms for high rock slopes are not well understood as yet. Doubts exist in relation to failure mechanisms, as well as to rock mass strength estimation in such scale. In recent years, there is a growing trend for the use of numerical analyses in order to study high rock slope stability, but they are not capable to reproduce all the phenomena involved. Analyses reported in the literature consider only the final configuration of the open pit, without taking into consideration the excavation evolution process, and damage induced to the rock mass resulting from this process. This work analyzes this effect and its consequences on the slope safety evaluation. Two dimensional stress strain analyses in rock slopes are described. Such analyses were conducted with linear elastic model and elasto plastic strain cohesion softening - friction hardening model considering the non-simultaneous mobilization of the strength components in the Mohr-Coulomb criterion, by including the rock mass damage. An approximate safety evaluation of a hypothetical slope shows that these considerations are very important. The stress path modifies the rock mass strength parameters close to the slope face by damage. The regions of the slope toe at each excavation stage are subjected to induced stress concentration causing damage to rock. This damage can explain the beginning of the progressive failure mechanism.
298

Using remote sensing and aerial archaeology to detect pit house features in Worldview-2 satellite imagery. : A case study for the Bridge River archaeological pit house village in south-central British Columbia, Canada.

Cooke, Sarah January 2017 (has links)
It is well known that archaeological sites are important sources for understanding past human activity. However, those sites yet to be identified and further investigated are under a great risk of being lost or damaged before their archaeological significance is fully recognized. The aim of this research was to analyze the potential use of remote sensing and aerial archaeology techniques integrated within a geographic information system (GIS) for the purpose of remotely studying pit house archaeology. As pit house archaeological sites in North America have rarely been studied with a focus in remote sensing, this study intended to identify these features by processing very high resolution satellite imagery and assessing how accurately the identified features could be automatically mapped with the use of a GIS. A Worldview-2 satellite image of the Bridge River pit house village in Lillooet, south-central British Columbia, was processed within ArcGIS 10.1 (ESRI), ERDAS Imagine 2011 (Intergraph) and eCognition Developer 8 (Trimble) to identify spatial and spectral queues representing the pit house features. The study outlined three different feature extraction methods (GIS-based, pixel-based and object-based) and evaluated which method presented the best results. Though all three methods produced similar results, the potential for performing object-based feature extraction for research in aerial archaeology proved to be more advantageous than the other two extraction methods tested.
299

Lasting Legacies of Hurricane, Harvesting, and Salvage Logging Disturbance on Succession and Structural Development in an Old-Growth Tsuga canadensis-Pinus strobus Forest

Sass, Emma 01 January 2017 (has links)
Disturbance events affect forest composition and structure across a range of spatial and temporal scales, and forest development may differ after natural, anthropogenic, or compound disturbances. Following large, natural disturbances, salvage logging is a common yet controversial management practice around the globe. While the short-term impacts of salvage logging have been studied in many systems, the long-term effects remain unclear. Further, while natural disturbances create many persistent and unique microsite conditions, little is known about the long-term influence of microsites on forest development. We capitalized on over eighty years of data on stand development following the 1938 hurricane in New England to provide the longest known evaluation of salvage logging impacts, as well as to highlight developmental trajectories for eastern hemlock (Tsuga canadensis)-white pine (Pinus strobus) forests under a variety of disturbance histories. Eight decades following disturbance, there were no differences in current overstory composition between areas that were logged, hurricane disturbed, or hurricane disturbed and salvage logged, but white pine declined across most sites. In contrast, structural characteristics remain distinct between the three management histories. In the unsalvaged area, the diversity of microsites and the coverage of uprootings and pits influenced overstory tree composition, diversity, and structural characteristics. These findings underscore the long-term influence of salvage logging on forest development and the importance of natural disturbance-mediated microsite conditions on tree species growth and survival. Future salvage logging efforts should consider these impacts and provide a greater range of unsalvaged areas across the landscape to maintain these important structural legacies over the long term.
300

Založení objektu v Karlových Varech / The Design of Foundation of Building in Karlovy Vary

Hrdý, Roman January 2014 (has links)
This thesis deals with the foundation of multifunctional building in Karlovy Vary. The aim of this thesis is to design a safe, economical and functional solutions for sheeting underground floors of the building and design of foundation structures.

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