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Grundförstärkning med pålar i berg : I befintlig konstruktion med begränsat utrymmeHöglund, Madicken, Larsson, Marcus January 2020 (has links)
This study has been done in order to examine which type of pile, pile driving- and waterproofing methodsare most suited for an existing building. A building that will undergo an extensive reinforcement of itsfoundation.The study has been made in regard to the following conditions:● Different types of clay soil (Cohesion soil)● Underlying rock structure with heavy incline (8° slope)● Sensitive environment for vibrations and ground displacements● Limited accessibility (Room and maximum weight)● Compressive and tensile forces● Pool (Water environment)To answer the questions of statement a scientific literature study, interview with a foundation expert,calculations in sizing, but also time and cost analysis has been conducted. A site visit to an object ofreference, Nya Krav Himmerfjärdsverket, occurred where a reconstruction of an existing building withextensive work of reinforcement to its’ foundation was in progress.The steel pipe pile with anchor and steel core pile are the best pile types in such conditions as compressiveand tensile forces, clay soil with underlying inclined rock bed, limited accessibility and sensitivesurrounding environment. Which pile type, pile driving- and waterproofing methods that are most suited forsuch conditions is different for each project. The steel core pile is more suitable for higher loads, rockstructures in incline and when verification of load capacity is not needed. At the same time the steel pipepile is more suited when the underlying rock bed is far below ground level, where you would need manypile elements and joints. In addition, the steel pipe pile is suitable for buildings with a complex loaddistribution, where a greater number of piles with lower load capacities is needed in order to satisfy this.The best pile driving method for drilling in sensitive environment is the water equipped down-the-hole(DTH) drill. This drilling method is gentle to surrounding piles in existing building.In order to minimise the risk of water penetration and then expand the life span of the construction, use ofa combination of different waterproofing systems is to prefer when waterproofing pile heads or pilefoundations.
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An axisymmetric finite element solution for elastic wave propagation through threaded connectionsLand, J. George 07 November 2008 (has links)
An axisymmetric finite element solution method is developed for axial wave propagation through a series of threaded connections in rock drills. A piston impacts axially on a string of rods held together by threaded joints and the wave propagates through these joints before reaching the bit. The energy lost in the joints limits the maximum effective depth of the drill. Several computational techniques are used to efficiently model the problem. Non-reflecting boundaries are used to numerically absorb the waves as they exit a joint. The stored waves are then re-initiated into the next joint eliminating modeling of the entire assembly of rods. The preload in the threads is modeled by shrinking the threaded sleeve onto the rods. A new dynamic relaxation damping scheme is used which starts with an undamped model and then increases the damping until the solution converges. This method converges more rapidly than the standard constant damping. / Master of Science
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Evaluating the Corrosion Performance of Mixed Material Stackups Fastened by Resistance Spot RivetsKrell, Paul David January 2020 (has links)
No description available.
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High Performance Steel for Percussive DrillingÅkerlund, Elin, Havo, Rebecka, Jonsson Åberg, Jakob, Österberg, Patrik, Fredriksson, Mikael January 2017 (has links)
Atlas Copco Secoroc AB are searching after new bulk materials for drill heads that are used in percussive drilling in order to improve their strength and durability. The aim of this project is to assist Atlas Copco in this search and provide them with further information regarding material properties, alloying elements, suppliers, etc. A literary study was carried out in order to identify materials that had UTS and KIC more than or equal to 1700 MPa and 70 MPa*m1/2, respectively. Materials that fulfilled these criteria were T250 grade maraging steel, Cobalt free maraging steel, High cobalt maraging steel, 300 grade maraging steel, AerMet 100, AF1410, S53, M54, 300M, 4340M and PremoMet. These were categorized into maraging steels, high alloy secondary hardened steels, and low alloy steels, and were then further researched. The material with the highest combination of UTS and KIC was M54 followed by AerMet 100; while AF1410 had the highest KIC but a low UTS, and PremoMet had the highest UTS but a low KIC. Maraging steels and HASH steels have a similar price range, while low alloy steels are much cheaper.
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High Performance Steel for Percussive DrillingÅkerlund, Elin, Jonsson Åberg, Jakob, Österberg, Patrik, Havo, Rebecka, Fredriksson, Mikael January 2017 (has links)
Atlas Copco Secoroc AB are searching after new bulk materials for drill heads that are used in percussive drilling in order to improve their strength and durability. The aim of this project is to assist Atlas Copco in this search and provide them with further information regarding material properties, alloying elements, suppliers, etc. A literary study was carried out in order to identify materials that had UTS and KIC more than or equal to 1700 MPa and 70 MPa*m^1/2, respectively. Materials that fulfilled these criteria were T250 grade maraging steel, Cobalt free maraging steel, High cobalt maraging steel, 300 grade maraging steel, AerMet 100, AF1410, S53, M54, 300M, 4340M and PremoMet. These were categorized into maraging steels, high alloy secondary hardened steels, and low alloy steels, and were then further researched. The material with the highest combination of UTS and KIC was M54 followed by AerMet 100; while AF1410 had the highest KIC but a low UTS, and PremoMet had the highest UTS but a low KIC. Maraging steels and HASH steels have a similar price range, while low alloy steels are much cheaper.
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Gibt es Parameter, die den Erfolg einer Minibohrlochtrepanation eines chronischen Subduralhämatoms vorhersagen? / Do we find parameters to predict success of twist-drill craniostomy in chronic subdural hematoma?Hoederath, Luisa 18 February 2019 (has links)
No description available.
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Multi-scale image analysis for process mineralogyGeorge Leigh Unknown Date (has links)
This thesis primarily addresses the problem of automatic measurement of ore textures by image analysis in a way that is relevant to mineral processing. Specifically, it addresses the following major hypotheses: • Automatic logging of drill core by image analysis provides a feasible alternative to manual logging by geologists. • Image analysis can quantify process mineralogy by physically meaningful parameters. • Multi-scale image analysis, over a wide range of size scales, provides potential benefits to process mineralogy that are additional to those available from small-scale analysis alone, and also better retains the information content of manual logging. • Image analysis can provide physically meaningful, ore-texture-related, additive regionalised variables that can be input to geostatistical models and the definition of domains. The central focus of the thesis is the development of an automatic, multi-scale method to identify and measure objects in an image, using a specially-developed skeleton termed the morphological CWT skeleton. This skeleton is a multi-scale extension of the morphological skeleton commonly used in image analysis, and is derived from the continuous wavelet transform (CWT). Objects take the form of hierarchical segments from image segmentation based on the CWT. Only the Mexican hat, also known as the Laplacian-of-Gaussian, wavelet is used, although other wavelet shapes are possible. The natural scale of each object is defined to be the size scale at which its CWT signal (the contrast between the interior and exterior of the object) is strongest. In addition to the natural scale, the analysis automatically records the mineral composition of both the interior and exterior of each object, and shape descriptors of the object. The measurements of natural scale, mineral composition and shape are designed to relate to: • The size to which ore must be broken in order to liberate objects. • Minerals that need to be separated by physical or chemical means once objects have been liberated. • Capability to distinguish qualitatively different ore-texture types that may have different geological origins and for which different processing regimes may provide an economic benefit. Measurements are taken over size scales from three pixels to hundreds of pixels. For the major case study the pixel size is about 50 µm, but the methodology is equally applicable to photomicrographs in which the pixel size is about 4 µm. The methodology for identifying objects in images contributes to the field of scale-space image segmentation, and has advantages in performing the following actions automatically: • Finding optimal size scales in hierarchical image segmentation (natural scale). • Merging segments that are similar and spatially close together (although not necessarily touching), using the structure of the morphological CWT skeleton, thus aiding recognition of complex structures in an image. • Defining the contrast between each segment and its surrounding segments appropriately for the size scale of the segment, in a way that extends well beyond the segment boundary. For process mineralogy this contrast quantifies mineral associations at different size scales. The notion of natural scale defined in this thesis may have applications to other fields of image processing, such as mammography and cell measurements in biological microscopy. The objects identified in images are input to cluster analysis, using a finite mixture model to group the objects into object populations according to their size, composition and shape descriptors. Each image is then characterised by the abundances of different object populations that occur in it. These abundances form additive, regionalised variables that can be input into geostatistical block models. The images are themselves input to higher-level cluster analysis based on a hidden Markov model. A collection of images is divided into different ore texture types, based on differences in the abundances of the textural object populations. The ore texture types help to define geostatistical domains in an ore body. Input images for the methodology take the form of mineral maps, in which a particular mineral has been assigned to each pixel in the image prior to analysis. A method of analysing unmapped, raw colour images of ore is also outlined, as is a new model for fracture of ore. The major case study in the thesis is an analysis of approximately 1000 metres of continuously-imaged drill core from four drill holes in the Ernest Henry iron-oxide-copper-gold ore deposit (Queensland, Australia). Thirty-one texture-related variables are used to summarise the individual half-metres of drill core, and ten major ore texture types are identified. Good agreement is obtained between locations of major changes in ore type found by automatic image analysis, and those identified from manual core logging carried out by geologists. The texture-related variables are found to explain a significant amount of the variation in comminution hardness of ore within the deposit, over and above that explained by changes in abundances of the component minerals. The thesis also contributes new algorithms with wide applicability in image processing: • A fast algorithm for computing the continuous wavelet transform of a signal or image: The new algorithm is simpler in form and several times faster than the best previously-published algorithms. It consists of a single finite impulse response (FIR) filter. • A fast algorithm for computing Euclidean geodesic distance. This algorithm runs in O(1) arithmetic operations per pixel processed, which has not been achieved by any previously published algorithm. Geodesic distance is widely used in image processing, for segmentation and shape characterisation.
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A 1700-year history of fire and vegetation in pine rocklands of National Key Deer Refuge, Big Pine Key, Florida charcoal and pollen evidence from Key Deer Pond /Albritton, Joshua Wright. January 2009 (has links)
Thesis (M.S.)--University of Tennessee, Knoxville, 2009. / Title from title page screen (viewed on Mar. 11, 2010). Thesis advisor: Sally P. Horn. Vita. Includes bibliographical references.
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Desenvolvimento inicial de Ricinus communis L. com substratos de torta de mamona e cascalho de perfura??o de po?os de petr?leo / Initial Ricinus communis L. development with substrates castor pie and drill cuttings of oil wellsLEITE, Thiago Ouverney 25 May 2015 (has links)
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Previous issue date: 2015-05-25 / CAPES / Petrobras / CNPq / FAPERJ / The drill cuttings is a residue of the oil industry produced during the drilling of onshore and offshore wells. Their mineralogical characteristics depend on the geological formation present along the perforation. Upon reaching the surface, it is impregnated with drilling fluid used during the process. The use of this waste in soils has been discussed as it has limitations per se (e.g. high content of Fe, Mn, Zn, Cu) as a consequence of the drilling process (e.g. Ba, Na and hydrocarbons - HTP). The purpose of this study was to investigate the decrease of salinity after the application of gravel with castor cake to the substrate and using the castor bean BRS- 149 cv. Nordestina, as plant indicator, to infer about limitations on the combined use of these wastes. Pots were used (8 dm3) with proportional doses of gravel (control, 5, 15, 30, 45 and 60 Mg ha-1) associated with castor cake (control, 2, 4, 8, 16 and 32 Mg ha-1) in a factorial design with three replications for 97 days after planting (DAP). Improvements were observed in the morphological development of castor bean plants, with the application of 60 Mg ha-1 gravel associated with 16 Mg ha-1 of castor cake. However, the dose of 60 mg ha-1 of gravel caused stress due to accumulation of Na in leaves, the same for the 45 mg h-1 dose. The best ratio of gravel and pie in this respect was of 15 and 32 mg h-1, respectively. After the initial cultivation of castor bean plants, it was found that the application of 30 Mg ha-1 of gravel was sufficiently capable to neutralizing the toxic Al3+; raising the pH to values around 6.5 and thus making the nutrients more avalilable to the crop. Also, there was a marked HTP decomposition (above 92%) from the substrate metabolical microbiological increase, with the pie addition. It was therefore concluded that the use of gravel must follow specific guidelines especially due to salinity, to avoid possible impacts caused to the environmental and the crop (castor bean). / O cascalho de perfura??o ? um res?duo da ind?stria do petr?leo produzido durante a perfura??o de po?os terrestres e mar?timas, cujas caracter?sticas mineral?gicas dependem da forma??o geol?gica presente ao longo da perfura??o. Ao chegar ? superf?cie, se encontra impregnado com fluido de perfura??o utilizado durante o processo. O uso deste res?duo no solo tem sido discutido com frequ?ncia por apresentar limita??es de ordem qu?mica, tanto de origem geol?gica (e.g. Fe, Mn, Zn, Cu) como provenientes do fluido de perfura??o (e.g. Ba, Na e Hidrocarbonetos - HTP). A proposta deste trabalho foi de averiguar a ameniza??o da salinidade ocasionada pela aplica??o de cascalho, adicionando torta de mamona ao substrato e utilizando a mamoneira BRS-149, cv. Nordestina, como planta indicadora, buscando orientar e inferir limita??es no uso conjunto destes res?duos. Foram utilizados vasos com capacidade de 8 dm3, utilizando doses proporcionais de cascalho (controle, 5, 15, 30, 45 e 60 Mg ha-1) associado a doses de torta de mamona (controle, 2, 4, 8, 16 e 32 Mg ha-1) em fatorial com tr?s repeti??es durante 97 dias ap?s plantio (DAP). Foram observadas melhorias no desenvolvimento morfol?gico da mamoneira, com a aplica??o de 60 Mg ha-1 de cascalho associado ? 16 Mg ha-1 de torta de mamona. Contudo, a dose de 60 Mg ha-1 de cascalho causou estresse por apresentar ac?mulo de Na nas folhas, o mesmo com a dose de 45 Mg ha-1, onde a melhor rela??o, de cascalho e torta, neste contexto, foi de 15 e 32 Mg ha-1, respectivamente. No que tange a melhoria do solo ap?s o cultivo inicial de mamona, foi constatado que a aplica??o de 30 Mg ha-1 de cascalho foi suficientemente capaz de neutralizar o Al3+ t?xico, na eleva??o do pH em torno de 6,5, e assim disponibilizando nutrientes para a cultura. Tamb?m verificou-se decomposi??o acentuada de HTP (acima de 92%) proveniente do metabolismo microbiol?gico no substrato, auxiliada pela adi??o de torta. Concluiu-se ent?o que o emprego do cascalho em solo deve seguir orienta??es espec?ficas e ponderadas, no que tange principalmente ? salinidade, para que n?o haja preju?zo ambiental e ? cultura da mamona.
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Taxa de utilização de sementes de soja no estado de Mato Grosso / Rate of soybean seeds use in the state of Mato GrossoSilveira, Helton Fleck da 20 April 2010 (has links)
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Previous issue date: 2010-04-20 / The application of good quality seeds is fundamental to farming
success. There is a close relationship between seed quality and productivity.
Estimation of seed utilization in the state of Mato Grosso, Brazil, provided by
ABRASEM in the last 10 years, shows seed utilization rate ranging 85 to 95%,
with setting around 90% in the last 3 crop seasons. Farmers make high utilization
of modern technology, thus demanding high yield seeds. The objective of this
study is to estimate the utilization rate of soybean seeds, and to verify utilization
conditions of available technologies for improving seeds yield. To estimate these
values a drill box survey method was used. A total of 220 samples were collected
over soybean producing regions of the state of Mato Grosso, Brazil, during the
2008/2009 crop planting season. Farming fields were visited at random at planting
time, where planter operators were approached and a sample of 1 kg was taken
from the drill box. In addition to collecting seed sample, which was also used to
assess mechanical damage, other information was obtained, in particular the
source of the seed used. After evaluation of seed quality and data analysis, a
commercial soybean seed utilization rate in the state of Mato Grosso, Brazil, was
found to be above 95%; estimates of over 45% of soybean farm fields are planted
with seeds which mechanical damage index is above ideal level; state of Mato
Grosso soybean farmers make use of top technology; over 95% of varieties are
protected, occupying 98,5% of soybean 2008/2009 crop cultivated area. / O uso de sementes de boa qualidade é fundamental para o sucesso
das lavouras. Há uma estreita relação entre a qualidade das sementes e a
produtividade. Estimativas de uso de sementes em Mato Grosso, divulgadas pela
Abrasem nos últimos 10 anos mostram que a taxa de utilização de sementes de
soja oscilou entre 85 e 95%, com acomodação em torno de 90% nas últimas três
safras. Considera-se ainda que os agricultores façam elevado uso de tecnologia
moderna, demandando sementes de alto desempenho. O objetivo deste trabalho
é estimar a taxa de uso de sementes de soja e aferir as condições de uso das
tecnologias disponíveis para a melhoria do desempenho das sementes. Para se
estimar estes valores, foi utilizado o método de amostragem na caixa da
semeadora. As amostras, 220 ao todo, foram coletadas nas regiões produtoras de
soja do estado de Mato Grosso, ao longo do período de semeadura da safra
2008/2009. As lavouras foram visitadas ao acaso, no momento da semeadura,
abordando-se o operador da semeadora e coletando-se uma amostra de 1 kg de
sementes da caixa da semeadora. Além da coleta da semente, que foi utilizada
para a avaliação de danificação mecânica, obtiveram-se outras informações,
sendo a mais importante a origem da semente utilizada. Após a avaliação da
qualidade das sementes e da análise dos dados levantados, constatou-se que a
taxa de utilização de semente comercial de soja no estado de Mato Grosso é
superior a 95%; estima-se que mais de 45% das lavouras de soja são
estabelecidas com sementes cujo índice de danificação mecânica está acima de
6%; os sojicultores do Estado de Mato Grosso utilizam alta tecnologia; 95,75%
dos cultivares em uso são protegidos, ocupando 98,5% da área total cultivada
com soja na safra 2008/2009.
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