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Otimização do Infill para redução das incertezas em um depósito sintético de cobre / Infill optimization to reduce uncertainty in a copper ore synthetic depositGustavo Zanco Ramos 19 September 2016 (has links)
A aquisição de novas informações de sondagem é realizada por intermédio do infill de furos de sonda e esta é uma prática utilizada em diversas etapas da exploração mineral. Métodos de otimização são largamente utilizados em várias fases e processos na vida da mina, por exemplo na otimização de cavas, na otimização do sequenciamento de lavra, entre outros. Contudo a utilização de métodos de otimização aplicados à locação de furos de inifill não é usual. Neste trabalho propõem-se utilizar a otimização matemática para melhorar a distribuição espacial dos novos furos, bem como para definir a quantidade adequada de furos a serem realizados. Métodos de otimização meta-heurísticos foram testados com o objetivo de minimizar duas funções objetivo que tratam das incertezas associadas à simulação dos dados, que são a soma da variância e a soma dos coeficientes de variação dos blocos simulados. O método que apresentou melhores resultados na otimização da função objetivo no menor tempo e custo computacional foi o método simulated annealing com resfriamento rápido e memória. Com base neste método de otimização comparou-se as funções objetivo propostas. Para efetuar a comparação amostraram-se os 11 furos definidos pela otimização para ambas as funções objetivo. O infill amostral foi realizado no corpo sintético e as comparações realizadas foram: a estatística descritiva - dos dados de infill comparados à população - e o gráfico Q-Q entre o e-type das simulações realizadas na base com infill e a população. A estatística descritiva do infill permitiu interpretar que a amostragem atualizada (soma das amostragens inicial e a nova) apresentou-se mais representativa do que a amostragem incial. Baseado no resultado dos gráficos Q-Q, a simulação calculada com o infill otimizando a minimização da soma dos coeficientes de variação apresentou maior aderência à população. / The acquisition of new drillhole information can be accomplished by the drill hole infill, a practice used in several steps of the mineral exploration. Optimization methods are widely used in several stages and processes of the mine life cycle, for example, mine pit optimization, mine scheduling optimization among others. However the optimization of drill hole infill locations are unusual. This work proposes the use of mathematical optimization to improve the spatial distribution and the number of the new drill holes to be made. Metaheuristics optimization methods were tested to minimize two objective functions that deal with the uncertainty associated to simulated data, the sum of the simulated blocks variance and the sum of the simulated blocks coefficient of variation. The best processing cost, processing time and results were obtained by simulated annealing method with fast cooling and memory for both objective functions. Based on this optimization method both proposed objective functions were compared. In order to perform the comparison 11 optimized drill holes locations by both objective functions were sampled. Sampling infill were done in the synthetic ore body and the made comparisons were: statistics - comparison between the infill data and population - and the QQ plot of the e-type statistics computed for simulation based on infill and population. Statistics for infill allowed to interpret that updated sample (the addition of new sampling in the initial data) was more representative than the initial sampling. Based on Q-Q plot the simulation computed for optimized infill location by the sum of the coefficient of variation minimization has more adherence to population.
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Técnicas adotadas e utilização de sementes de soja em Rondonópolis, Mato Grosso / Rate of Soybean seeds use in the Rondonópolis, Mato GrossoCalaça, Antonio João Moreira 29 August 2011 (has links)
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Previous issue date: 2011-08-29 / The application of good quality seeds is fundamental to farming success. Estimation
of seed utilization in Rondonópolis, 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 100 samples were collected over soybean
producing regions of Rondonópolis, in the state of Mato Grosso, Brazil, during the
2010/2011 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 Rondonópolis, in the state of Mato Grosso, Brazil,
was found to be above 88%; estimates of over 54% of soybean farm fields are
planted with seeds which mechanical damage index is above ideal level; in
Rondonópolis, state of Mato Grosso soybean farmers make use of top technology;
over 100% of varieties are protected. / A taxa de utilização de sementes (TUS) de uma determinada cultura indica o
percentual da área total que é estabelecida com sementes comerciais. No Brasil
atualmente, a TUS, para a cultura da soja situa-se na faixa de 64%.
O uso de sementes de boa qualidade é fundamental para o sucesso das lavouras.
Estimativas de uso de sementes em Mato Grosso, 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 adotem elevado uso de tecnologia moderna, demandando sementes de
alto desempenho. O objetivo deste trabalho foi estimar a taxa de uso de sementes
comerciais de soja e aferir as condições de uso das tecnologias disponíveis para a
melhoria do desempenho das sementes. Para obtenção destes valores, foi utilizado
o método de amostragem na caixa da semeadora. Um total de 100 amostras, foram
coletadas nas propriedades produtoras de soja do município de Rondonópolis, ao
longo do período de semeadura da safra 2010/2011, quando simultaneamente se
aplicou um questionário visando aferir as tecnologias adotadas pelos produtores. As
lavouras foram visitadas ao acaso, no momento da semeadura, abordando-se o
operador da semeadora e coletando-se uma amostra de 1 (um) 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, através da aplicação do
questionário, sendo a mais importante à origem da semente utilizada. Após a
análise dos dados levantados, constatou-se que a taxa de utilização de semente
comercial de soja no município de Rondonópolis na safra 2010/2011 foi de 88%
(oitenta e oito por cento).
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Automated Device to Measure Slurry Properties in Drilled ShaftsMullins, Miles Patrick 01 July 2016 (has links)
Slurry is the fluid within a drilled excavation that is introduced when an excavation is deeper than the water table or where additional stability is needed for loose sandy dry soils. Although construction practices vary greatly throughout the country and the world, slurry levels should be maintained above the existing ground water level by a suitable margin. The most widely used slurry type is mineral slurry formed by mixing dry clay powder with water; either bentonite or attapulgite powder may be used (attapulgite being used in saline water conditions). Regardless of whether the slurry material is mineral, polymer or natural, the construction practice must address the slurry properties to ensure the stability of the excavation is never compromised.
Proper performance of slurries used to stabilize drilled shaft excavations is maintained by assuring the density, viscosity, pH, and sand content stay within specified limits. These limits have been set either by past experience, research findings and/or by manufacturer recommended values. However, field slurry testing is time consuming as all measurements are manually performed. With the overwhelming advances in digital down-hole devices, it is not unreasonable to assume that slurry property tests are equally applicable to this trend. This formed the basis of this project.
The most commonly used test to indicate slurry viscosity is the Marsh Funnel Test which is essentially a timed flow for a fixed volume of slurry to exit a falling head funnel. Using a library of unique pressure versus flow rate responses for a wide range of slurry viscosities, an automated downhole device was designed and tested that incorporated this information to estimate viscosity in the excavation without the need to remove slurry in order to test. Direct measurement of slurry density was also incorporated into the device and the sand content was computed from density and the viscosity where the suspended solids that make up the density stems from both the slurry products and the soil cuttings.
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Wear and degradation of rock drill buttons with alternative binder phase in granite and sandstoneHolmberg, Anders January 2017 (has links)
In this thesis, drill bit buttons with cobalt, nickel and iron binders in different compositions have been tested against granite and sandstone and the wear and friction have been measured. Furthermore, the wear and degradation of the buttons have been categorized. Buttons with cobalt binder were tested against granite and sandstone and buttons with alternative binders (Ni, Fe, Co) were tested against granite. Cobalt buttons were used as a reference and the wear and friction of the alternative binders was compared to the reference. The amount of worn rock was also measured. Furthermore, post treated drill bit buttons with a composition of Fe-Ni-Co were compared to buttons with the same composition that had not been post treated The results show that buttons with an alternative composition of Fe-Co-Ni and Fe- Ni wears less than the cobalt reference. The post treatment process does not decrease the wear of the drill bit but lowers the deviation from the mean wear. The amount of worn rock does not differ between the samples except for between the post treated and not post treated buttons with a composition of Fe-Ni-Co. The post treated buttons produces more rock debris than the not post treated. No apparent difference could be seen on the surface of the tested buttons after the test. However, composition specific cracks could be found underneath the surface of the samples. EDS-analysis showed signals of oxygen inside of all of the investigated cracks. For some compositions at depths of 20 micrometers. The curves of friction shows similar appearance but the values of the coefficient of friction differs. No apparent correlation was found between the wear and friction of the samples. Furthermore, no apparent correlation was found between the hardness and the wear of the buttons.
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Návrh a konstrukce CNC routeru pro DPS / CNC router for PCBGerják, Rastislav January 2017 (has links)
In mechanical industry, both additive and subtractive manufacturing methods are controlled by instructions in G-code, making it possible to utilize both technologies in one modular device. Main objective is to design, construct, and calibrate multipurpose machine based on RepRap 3D printer, which will be able to use attached spindle to precisely mill light materials. Particular emphasis is given to ability to carve a pattern and drill holes in plated substrate in order to create functional PCB by incision.
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Obrábění vulkanizačních forem z hliníkových slitin / Machining of vulcanizing molds from aluminum alloysKaška, Zdeněk January 2020 (has links)
This diploma thesis is focused on the issue of deep drilling of vulcanization molds from various aluminum alloys. The work will describe a brief description of machined materials and tools for deep drilling, including the production of the vulcanization mold itself. Based on experimental measurements, the analysis of data and knowledge gained from deep drilling of aluminum alloys with different silicon contents will be performed. In the end, the individual components of force loads for both machined materials will be compared
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Návrh robotizovaného pracoviště na montáž vrtačkových sklíčidel / Design of robotized workplace for assembly of drill chucksKoutňák, Jan January 2020 (has links)
Master's thesis is focused on design of robotized workplace for assembly of drill chucks. In the first part the fundamental issue is described. The next part contains an analysis of selected chuck, which continues with design of robotized workplace including components. The thesis is also focused on a work cycle design, risk analysis and economic evaluation. Drawing documentation, 3D workplace model and work cycle simulation video is attached.
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Vrtací jednotka / Drilling UniteGlembek, Jan January 2008 (has links)
The goal of this work is a design of a hydraulic drilling unit and a manipulator for the PSU 9000 machine. The introduction describes the use of underground mining drilling machines and mentions some of the current solutions. The second part contains the design and calculations of individual components. In the final part, the finite-element method is used for calculation of the bearing parts of the construction.
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Technologie výroby kombinovaných řezných nástrojů / Technology of production combinated cutting toolsRusz, Radek January 2012 (has links)
In the thesis is solved manufacturing technology of step drill from material of cemented carbide. At first is made review of existing shank cutting tool types, after that follows an analysis of cemented carbide tool material. In the next part of thesis is manufacturing technology of this tool, including review of grinding wheels, designed. Output of this work is procedure of program designing for manufacturing this tool in software Numroto. Next output is techno-economic evaluation of step hole manufacture with combined tool and comparison to conventional type of manufacture.
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Racionalizace technologie vrtání / Rationalisation of drilling technologyRozum, Josef January 2014 (has links)
Master's thesis focus on the rationalisation of the holes drilling technology in the bearing rings which are defined for wind generators. This work contains review of drilling tools, analysis of the current state and proposal of rationalising precautions. Rationalising precautions are focused mainly on the adequate choice of the drilling technology and applied tools. The most suitable option was chosen for the drilling of holes according to the economical evaluation.
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