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Monitoramento de taludes via radar SSR como indicador chave de desempenho geotécnico integrado às atividades primárias da cadeia de valor mineral. / Slope monitoring via SSR radar as a geotechnical key performance indicator integrated to the primarily activities of the mineral value chain.Alizeibek Saleimen Nader 27 November 2012 (has links)
O avanço da tecnologia da informação e da aplicação de computadores na indústria de mineração permitiu a automatização de várias atividades da cadeia de valor mineral (CVM). As atividades da cadeia de valor mineral podem ser divididas em atividades de suporte e em atividades primárias. Os sistemas ERP (Enterprise and Resource Planning) têm fornecido por muitos anos a plataforma para a integração eficiente das atividades de suporte da mineração. No entanto, apesar dos avanços obtidos com a aplicação dos computadores em nichos técnicos específicos, não se conseguiu até o presente momento, integrar efetivamente as atividades primárias da cadeia de valor mineral. As principais razões para isto, são tanto as incertezas existentes no processo produtivo, que diferentemente de outros setores industriais são intrínsecas ao negócio da mineração, quanto as dificuldades para se medir e gerenciar convenientemente os indicadores chave de desempenho (KPIs-Key Performance Indicators), relevantes à cadeia de valor mineral. A medição e controle dos KPIs é fundamental para a quantificação dos eventuais benefícios da aplicação de tecnologia e do potencial de retorno do investimento em recursos humanos e financeiros, necessários à integração das atividades primárias da cadeia de valor mineral. Esta tese não se propõe a integrar a cadeia de valor mineral, mas a demonstrar como a integração da atividade geotécnica da CVM gera benefícios tangíveis, que permitem antever os benefícios de sua completa integração e assim a tese avança a um ponto do controle geotécnico que é o monitoramento da estabilidade de taludes em minas em operação, para demonstrar que a aplicação de metodologias de monitoramento e controle adequadas, impactam positivamente nos KPIs e consequentemente nas atividades da cadeia de valor mineral, relacionadas a eles. O objetivo desta tese é também o de comprovar a importância do monitoramento eficaz dos KPIs para a integração das atividades geotécnicas da cadeia de valor mineral exemplificando seu impacto na eficiência, qualidade e economicidade dos processos envolvidos e assim, comprovar a eficaz possibilidade de integração destas atividades da cadeia de valor mineral e a possibilidade de extrapolação da integração para o restante da mesma. Neste sentido o trabalho desenvolve-se primeiramente no intuito de determinar os principais KPIs controlados em algumas das mais importantes empresas de mineração brasileiras. Pela correta identificação das métricas e do contexto gerencial em que estes estão inseridos é possível demonstrar a importância e o impacto de seu mapeamento e medição para a gestão efetiva do negócio da mineração. Uma nova tecnologia de monitoramento de taludes que faz uso de equipamentos de radar imageadores é apresentada e explicada, assim como vários exemplos de sua utilização ao redor do mundo são descritos, ressaltando-se os resultados obtidos e sua influência na medição e gerenciamento dos KPIs envolvidos. Finalmente, uma nova metodologia escalonada e com pontos de decisão é proposta para a integração da cadeia de valor mineral e aplicada a dois projetos desenvolvidos pelo autor, que são apresentados e discutidos para demonstrar e comprovar os benefícios econômicos advindos de sua aplicação. Para esses projetos, o autor planejou e executou a coleta de dados, procedeu a suas análises, avaliou seus impactos econômicos e comprovou a relevância do estudo realizado. / The advance of information technology and computer application to the mining industry has allowed the automation of several activities of the mineral value chain (MVC). The activities of the mineral value chain can be divided in support and primarily activities. ERP (Enterprise and Resource Planning) systems have provided, for many years, the platform for the efficient integration of the support activities in mining. Despite all the advance gathered with the application of computers to specific technical niches, the effective integration of the primarily activities of the mineral value chain has not been obtained to date. The main reasons for this fact are the uncertainties existent in the production process that differently from other industrial sectors, are intrinsic to the mining business, as well as the difficulties to measure and manage the key performance indicators (KPIs) that are relevant to the mineral value chain. The measurement and control of KPIs is fundamental for quantifying the eventual benefits of the application of technology and the potential for the return of the investments in human and financial resources, needed to integrate the primarily activities of the mineral value chain. This thesis is not aimed at integrating the mineral value chain, but to demonstrate how the integration of the geotechnical activity of the MVC generates tangible benefits that allow foreseeing the benefits of its complete integration, so this thesis reaches a point of the geotechnical control that is the slope stability monitoring of operational mines, in order to demonstrate that the application of adequate methodologies of monitoring and control, impact positively on the KPIs and consequently on the activities of the mineral value chain related to them. The objective of this thesis is also to prove the importance of the effective monitoring of KPIs for the integration of the geotechnical activities of the mineral value chain and its impact in the efficiency, quality and economics of the processes involved, in order to prove the effective possibility of the integration of this activity of the mineral value chain thus demonstrating the possibility to extrapolate the integration results to the remaining chain inter-activities. In this sense, the work is developed primarily with the aim of determining the main KPIs that are controlled in some of the most important Brazilian mining companies. Through the correct identification of the metrics and management context in which they are inserted, it is possible to demonstrate the importance and impact of their mapping and measurement for the effective management of the mining business. A new technology for slope monitoring that uses imaging radar equipment is presented and explained as well as several examples of its utilization around the world are described, emphasizing the results obtained and their influence for the measurement and management of the involved KPIs. Finally, a new staggered methodology, with decision points is proposed for the integration of the mineral value chain and applied to two projects developed by the author, which are presented and discussed in order to demonstrate and to prove the economic benefits obtained from its application. For these projects, the author planned and executed the data collection, data analysis, economic assessment and proved the relevance of the work performed.
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Limites críticos topográficos de feições erosivas lineares em Piratininga (SP) / Topographical threshold of gully erosions in Piratininga (SP)Rodrigo Augusto Stabile 30 January 2013 (has links)
Considerando a importância de se definir as condições críticas para a deflagração, desenvolvimento e estabilização das voçorocas e outras feições erosivas lineares, e tendo em conta as poucas abordagens nesse sentido realizadas no Brasil, o objetivo geral desta pesquisa é avaliar os limites críticos topográficos para o desenvolvimento das formas resultantes da erosão linear em Piratininga (SP). Os procedimentos metodológicos envolveram a identificação e caracterização das feições erosivas por meio de fotografias aéreas e in situ; a mensuração da declividade (S) em campo e com diversas resoluções de Modelo Digital de Terreno (MDT) e da Área de Contribuição (A) também a partir do MDT; e, a definição dos limites críticos topográficos na forma da seguinte Função Potência: S = a × . A linha do limite crítico foi ajustada no limite inferior dos dados, paralelamente à inclinação linha ortogonal de regressão de S e A. As feições erosivas foram categorizadas em 4 classes e 13 subclasses de acordo com seus aspectos morfométricos e indicadores dos processos atuantes. A mensuração de S e A por diferentes métodos resultou em algumas variações significativas nos dados gerados, sobretudo na comparação entre os valores obtidos em campo e pelo MDT. Foi obtido o seguinte limite crítico topográfico: S = 0,064 × ,, que tem coeficientes semelhantes a outras pesquisas que analisaram feições erosivas resultantes do escoamento subsuperficial. A distinção entre as feições erosivas onde ainda há indícios de recuo das cabeceiras e feições erosivas que já atingiram o equilíbrio, assim como a análise dos pontos de início dos processos erosivos em relação ao limite crítico, forneceu bases empíricas para a discussão da evolução das feições erosivas lineares em relação ao limite crítico topográfico e também para ao entendimento dos estados estável e instável dos voçorocamentos, permitindo a construção de um modelo teórico de previsão da estabilidade e instabilidade das feições erosivas baseado na relação entre a declividade e a área de contribuição em diferentes perfis de encosta. / Considering the importance of defining the critical conditions for the generation, development and stabilization of gullies and other erosional features, and taking into account the few approaches accordingly held in Brazil, the aim of this research is to evaluate the topographical critical limits for developing of gully erosion in Piratininga (SP). The methodological procedures involved: the identification and characterization of the gullies using aerial photographs and in situ; measurement of the slope (S) in the field and with various resolutions of Digital Terrain Model (DTM) and drainage area (A) also from DTM, and the definition of topographical thresholds in the form of following Power Function: S = a × . The topographical threshold line has been set at the lower limit of data, parallel to the slope of orthogonal regression line of S and A. The erosional features were categorized into 4 classes and 13 subclasses according to their morphometric aspects and indicators of active processes. The measurement of S and A by different methods resulted in some significant changes in the data generated, particularly when comparing the values obtained in the field and the DTM. We obtained the following topographic threshold: S = 0,064 × , which has coefficients similar to other studies that analyzed erosional features resulting from subsurface flow. The distinction between active and stabilized gullies, as well as analysis of the starting points of erosion in relation to threshold line, provide an empirical basis for the discussion of the evolution of gullies in relation to the topographic threshold line and also for the understanding of stable and active states of gullies, allowing the construction of a theoretical model for predicting the stability and instability of the gullies based on the relationship between slope and drainage area in different slope profiles.
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Análise paramétrica da infiltração e sua influência na estabilidade de taludes em solo não saturado / Parametric analysis of infiltration and its influence on unsaturated soil slope stabilityCláudio Rodrigues dos Santos 24 March 2004 (has links)
Apresenta-se um estudo paramétrico acerca da infiltração de água e sua repercussão no Fator de Segurança de talude em solos não saturados. Na análise adota-se um talude de referência com geometria fixada conforme a inclinação típica para taludes em areia argilo siltosa, característica do Centro-Oeste do estado de São Paulo. A análise paramétrica foi desenvolvida a partir de uma simulação de fluxo em regime transiente utilizando o programa SEEP/W, que utiliza o método de elementos finitos, e posteriormente uma análise de estabilidade do talude de referência utilizando o método de Bishop simplificado conforme apresentado no programa SLOPE/W. Foram analisados taludes homogêneos compostos por três diferentes tipos de solo, uma areia, um silte argiloso e uma areia argilo siltosa. Os parâmetros analisados compreendem a curva de retenção de água, a função condutividade hidráulica do solo e a intensidade de precipitação. Verificou-se que a função condutividade hidráulica e a pressão de entrada de ar são os principais determinantes do comportamento da infiltração e conseqüentemente da estabilidade do talude. As simulações de fluxo evidenciaram que os taludes em solos mais arenosos apresentam taxas de infiltração maiores que as apresentadas pelos taludes compostos por solos siltosos. Consequentemente, os escorregamentos ocasionados pela perda da contribuição da sucção para a resistência ao cisalhamento ocorrem primeiramente nos taludes compostos por solos arenosos e posteriormente naqueles compostos por solos siltosos, fato este que pôde ser confirmado pelas análises de estabilidade do talude de referência. / A parametric study is presented about water infiltration and its repercussion in the safety factor of unsaturated soil slopes. In the analysis it is adopted a reference slope with determined geometry according to the typical inclination for slopes in silty clayey sand, characteristic of the mid-western region of São Paulo State, in Brazil. The parametric analysis was developed from a flux simulation in transient regime using the SEEP/W software, which uses the finite elements method, and thereafter, a stability analysis of the reference slope using simplified Bishop method, as presented in the SLOPE/W software. Homogeneous slopes composed by three different types of soil (sand, clayey silt and silty clayey sand) were considered. The analyzed parameters include the water retention curve, the hydraulic conductivity function and the precipitation intensity. It was verified that the hydraulic conductivity function and the air entry value are the main determinants of the infiltration behavior and, subsequently, of the slope stability. The flux simulations have evidenced that coarser soils slopes show higher infiltration rates than the ones presented in finer soil slopes. Consequently, the slides caused by the loss of the suction\'s contribution to shear strength occur primarily in coarser soil slopes than in fine soil slopes, what could be verified in the stability analysis of the reference slope.
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A família Orchidaceae em um fragmento florestal no sul do Rio Grande do Sul, Brasil / Family Orchidaceae in a Forest Fragment in the South of Rio Grande do Sul, Brazil.Perleberg, Tângela Denise 04 May 2009 (has links)
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Previous issue date: 2009-05-04 / Rio Grande do Sul state south region is not well-known as for its forests floristic
composition. This work conducted a taxonomic treatment of Orchidaceae species
occurring in Morro Quilongongo, a seasonal semi-deciduous forest fragment located
in Southeast Slope, in the municipality of Pelotas, Rio Grande do Sul state. The work
shows descriptions, identification key and illustrations of the species, complemented
with data about habitat, phenology and geographic distribution. Forty species of
Orchidaceae were found distributed in 22 genders. The most representative genders
in number of species were Oncidium (8 spp.), Acianthera (4 spp.), Anathallis and
Specklinia (3 spp. for each of the plants), however, 14 genders (64%) presented only
one specie. The most found species, 29 (72%), are epiphyte, 9 of them are
frequently observed upon the rocks. Eleven (27.5%) are terrestrial, seven are
frequently found occurring in rocks. The number of species in bloom by month varied
from 8 to 14. In September and October a larger number of species come into bloom.
In April and July a smaller number of species come into bloom. The regions of Rio
Grande do Sul which presented the largest number of these species were the
Superior Northeast Slope (30 spp.), Central Depression (27 spp.) and Coast (26
spp.). The Orchidaceae flora of the region is not much represented in the consulted
herbaria; just only 11 (27.5%) species found in Morro Quilongongo have a
representative exsiccate of the region of Pelotas. Therefore, this work contributes to
the knowledge of the South region flora of Rio Grande do Sul, providing data that
justify the preservation of this area. / A região sul do Rio Grande do Sul é pouco conhecida quanto à composição florística
de suas florestas. Neste trabalho foi realizado o tratamento taxonômico das espécies
de Orchidaceae ocorrentes no Morro Quilongongo, um fragmento de floresta
estacional semidecidual, localizado na Encosta do Sudeste, no município de Pelotas,
Estado do Rio Grande do Sul. São apresentadas descrições, chave de identificação
e ilustrações das espécies, complementadas com dados sobre habitat, fenologia e
distribuição geográfica. Foram encontradas 40 espécies de Orchidaceae distribuídas
em 22 gêneros. Os gêneros mais representativos, em número de espécies, foram
Oncidium (8 spp.), Acianthera (4 spp.) e Anathallis e Specklinia (3 spp. cada),
porém, 14 gêneros (64%), apresentam apenas uma espécie. A maioria das espécies
encontradas, 29 (72,5%), é epífita, sendo 9 destas também observadas
frequentemente sobre rochas. Onze (27,5%) são terrestres, sendo 7 frequentemente
encontradas como rupícolas. O número de espécies floridas por mês variou de 8 a
14, sendo setembro e outubro os meses com maior número de espécies floridas e
abril e julho os meses com menor número de espécies floridas. As regiões do Rio
Grande do Sul que apresentaram o maior número de espécies comuns à área de
estudo foram a Encosta Superior do Nordeste (30 spp.), Depressão Central (27 spp.)
e Litoral (26 spp.). A flora de Orchidaceae da região é pouco representada nos
herbários consultados, sendo que apenas 11 (27,5%) espécies encontradas no
Morro Quilongongo possuem uma exsicata representativa da região de Pelotas.
Portanto, o trabalho contribui para o conhecimento da flora da região sul do Rio
Grande do Sul gerando dados que justificam a preservação da área.
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When mathematics teachers focus discussions on slope : Swedish upper secondary teachers in a professional development initiativeBengtsson, Anna January 2014 (has links)
The shift towards collegiality is a new setting for many teachers. Most teachers work alone, in isolation from their colleagues and collegial collaboration requires organisational structures. The aim of the study is to describe and analyse upper secondary mathematics teachers’ collective practice,developed in a professional development initiative. This study is a case study and the empirical data is generated through observations and an interview of a group of four teachers at a school who met on a weekly basis throughout a term. Their discussions focused on the mathematical concept of slope in a setting of learning study. This thesis is the case of when mathematics teachers focus discussions on slope and draws on Wenger’s Communities of Practice Perspective, as a unitof analysis, and addresses the question: What are the characteristics of practice when upper secondary mathematics teachers focus discussions on slope in the setting of a learning study? The analysis accounts for characteristics of the aspects of practice, through the coherence of mutual engagement, joint enterprise and shared repertoire in the community of practice. The teachers are engaged around finding small changes in their teaching that could give major effect in students learning. They negotiate what the students need to know in order to understand the relation between Δy and Δx. The characteristic of practice is a conceptual mapping of the concept of slope. It reveals students’ partial understanding of related concepts due to how they were given meaning through previous teaching. The conceptual mapping of slope goes back as far as to the student’s partial understanding of the meaning of subtraction. However, what emerges is in relation to the teachers’ experience of avoiding students’ difficulties with negative difference when teaching slope. It turns out to be a negotiation and a renegotiation of teaching slope for instrumental understanding or conceptual understanding. An overall characteristic of practice is that it develops in a present teaching culture.
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Variable Patterns in Spur and Groove Reef Morphology Explained by Physical Controls and their Relevance for Platform-Top SedimentologyGardiner, Robert C, Jr 12 May 2017 (has links)
Spur and groove (SaG) morphology is a common ornamentation of reef-armored Holocene carbonate platform margins. Composed of margin-normal promontories constructed of coral framestone, termed “spurs”, interleaved with similarly orientated gullies, “grooves”, this morphology varies based on a host of physical controls. Primarily, the surrounding oceanographic conditions as well as the size and shape of the platform the SaG is encompassing, directly influence the development and organization of SaG. Since grooves act as conduits for carbonate sediment transport, this study seeks to examine the relationship between SaG organization dictated by platform size and shape and how that in turn influences platform-top sedimentation. The analysis reveals trends that suggest platform shape plays a larger role than platform size in allowing highly organized SaG to develop on multiple margins around the platform. In turn, those trends would suggest these sites to have more stable platform top sediment deposits. However, many variables go in to the creation and maintenance of platform top cays. While this study enhanced the current understanding of how oceanographic conditions influence SaG development and organization, expanding on the concepts and results found in this study coupled with coring data of SaG and platform-top cays, could further link the connection between SaG and sediment transport.
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Pure-injective modules over tubular algebras and string algebrasHarland, Richard James January 2011 (has links)
We show that, for any tubular algebra, the lattice of pp-definable subgroups of the direct sum of all indecomposable pure-injective modules of slope r has m-dimension 2 if r is rational, and undefined breadth if r is irrational- and hence that there are no superdecomposable pure-injectives of rational slope, but there are superdecomposable pure-injectives of irrational slope, if the underlying field is countable.We determine the pure-injective hull of every direct sum string module over a string algebra. If A is a domestic string algebra such that the width of the lattice of pp-formulas has defined breadth, then classify "almost all" of the pure-injective indecomposable A-modules.
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Comparative Studies On Slope Stability AnalysisBijoy, A C 05 1900 (has links) (PDF)
No description available.
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Artificial Environments and Spatial Travel Implications: The case of Madrid Snow ZoneLipasti, Johannes January 2017 (has links)
Place has been a fundamental topic for geographers (Agnew, 1987). It stands both for a study object and a manner of perceiving the world. This thesis departs from the theoretical debate regarding places and how places are considered as being spatially fixed in the sense that places cannot be reproduced or imitated elsewhere. However, technological innovations have extraordinary significance in all the realms of leisure and lifestyle (Godbey, 1997) whereas, leisure activities increasingly are being simulated and reproduced exemplifying the new postmodern culture and the ‘post-tourist’ (Urry, 1990). Thus, challenges the spatial fix of places (Shaw & Williams, 2004). There has been little empirical research regarding artificial environments and therefore, the research problem contributes to understand how artificial environments are altering habitual travel patterns regarding the ‘genuine’ or as previous authors have stated, regarding the ‘real thing’. The research questions proposed for the study, directed the researcher to a quantitative approach using the questionnaire as a main source of data collection. The simulated environment that was investigated in the study was the indoor ski slope located in Madrid (Spain). The results showed that the simulated environment is enhancing and intervening the ski activity. For most of the skiers the indoor ski slope is complementing their ski activity in front of the outdoor ski resorts. Furthermore, the facility is recruiting every year a great number of new skiers that after skiing indoors desire to experience the ‘real thing’. Due to the proximity of the facility to the major urban areas, the indoor ski slope is acting as an intervening opportunity and boosting the visitors towards outdoor skiing.
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Landscape partitioning and burial processes of soil organic carbon in contrasting areas of continuous permafrostPalmtag, Juri January 2017 (has links)
Recent studies have shown that permafrost soils in the northern circumpolar region store almost twice as much carbon as the atmosphere. Since soil organic carbon (SOC) pools have large regional and landscape-level variability, detailed SOC inventories from across the northern permafrost region are needed to assess potential remobilization of SOC with permafrost degradation and to quantify the permafrost carbon-climate feedback on global warming. This thesis provides high-resolution data on SOC storage in five study areas located in undersampled regions of the continuous permafrost zone (Zackenberg in NE Greenland; Shalaurovo and Cherskiy in NE Siberia; Ary-Mas and Logata in Taymyr Peninsula). The emphasis throughout the five different study areas is put on SOC partitioning within the landscape and soil horizon levels as well as on soil forming processes under periglacial conditions. Our results indicate large differences in mean SOC 0–100 cm storage among study areas, ranging from 4.8 to 30.0 kg C m-2, highlighting the need to consider numerous factors as topography, geomorphology, land cover, soil texture, soil moisture, etc. in the assessment of landscape-level and regional SOC stock estimates. In the high arctic mountainous area of Zackenberg, the mean SOC storage is low due to the high proportion of bare grounds. The geomorphology based upscaling resulted in a c. 40% lower estimate compared to a land cover based upscaling (4.8 vs 8.3 kg C m-2, respectively). A landform approach provides a better tool for identifying hotspots of SOC burial in the landscape, which in this area corresponds to alluvial fan deposits in the foothills of the mountains. SOC burial by cryoturbation was much more limited and largely restricted to soils in the lower central valley. In the lowland permafrost study areas of Russia the mean SOC 0–100 cm storage ranged from 14.8 to 30.0 kg C m-2. Cryoturbation is the main burial process of SOC, storing on average c. 30% of the total landscape SOC 0–100 cm in deeper C-enriched pockets in all study areas. In Taymyr Peninsula, the mean SOC storage between the Ary-Mas and Logata study areas differed by c. 40% (14.8 vs 20.8 kg C m-2, respectively). We ascribe this mainly to the finer soil texture in the latter study area. Grain size analyses show that cryoturbation is most prominent in silt loam soils with high coarse silt to very fine sand fractions. However, in profiles and samples not affected by C-enrichment, C concentrations and densities were higher in silt loam soils with higher clay to medium silt fractions. / <p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>
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