970 resultados para In-Drilling Alignment


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An analysis of a stretch of coastline shows multiple alterations through environmental climate actions. The narrow, fragile line displays singularities due to three basic causes. The first is the discontinuity in feed or localised loss of solid coastal material. Called massics, their simplest examples are deltas and undersea canyons. The second is due to a brusque change in the alignment of the shoreline’s edge, headlands, groins, harbour and defence works. Given the name of geometric singularities, their simplest uses are artificial beaches in the shelter of a straight groin or spits. The third is due to littoral dynamics, emerged or submerged obstacles which diffract and refract wave action, causing a change in the sea level’s super-elevation in breaker areas. Called dynamics, the simplest examples are salients, tombolos and shells. Discussion of the causes giving rise to variations in the coastline and formation of singularities is the raison d’être of investigation, using actual cases to check the suitability of the classification proposed, the tangential or differential action of waves on the coastal landscape in addition to possible simple, compound and complex shapes detected in nature, both in erosion and deposit processes

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Os empreendimentos de mineração comumente demandam grande quantidade de investimentos financeiros e, na maioria das vezes, longos períodos de implantação, o que os torna altamente sujeitos a diversas fontes de incertezas. Tais incertezas comumente tendem a diminuir conforme a evolução do projeto. O objetivo deste estudo é correlacionar as incertezas associadas ao modelo de teores de cobre do depósito Sequeirinho com o volume de investimentos realizados ao longo de distintas fases da pesquisa geológica. Este depósito insere-se no contexto do Complexo de Mineração Sossego, localizado no município de Canaã dos Carajás (PA). Primeiramente, foram realizadas 100 simulações para cada domínio litológico em cada campanha de sondagem (pré-1998, 1999, 2000, 2002 e 2003) a partir do método de simulação sequencial gaussiana condicionada aos dados amostrais, totalizando 1.400 possíveis cenários. Para a avaliação das incertezas foram calculados três índices: variância condicional, coeficiente de variação condicional e intervalo interquartil. Por fim, a avaliação dos investimentos foi elaborada a partir dos custos estimados para o desenvolvimento de sondagens e análises químicas. Desde a campanha pré-1998, houve uma tendência de os teores médios do depósito aproximarem-se dos prováveis valores reais observados nas fases finais da pesquisa. No ano de 2000 ocorreu o maior investimento (cerca de 28 milhões de Reais) e a redução das incertezas atingiu o patamar de 15%. Os investimentos desenvolvidos em sondagens posteriores à campanha de 2000 foram da ordem de 9 milhões de Reais (cerca de 12 mil metros de sondagem), porém, não foram constatadas reduções significativas das incertezas. Este investimento seria melhor aproveitado caso fosse redirecionado a novas áreas de prospecção. Além do montante financeiro necessário para a redução das incertezas, foco deste estudo, as variações na interpretação geológica e a locação dos furos de sondagem são variáveis importantes na análise de incertezas associadas aos investimentos em pesquisa geológica.

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In this paper we present an automatic system for the extraction of syntactic semantic patterns applied to the development of multilingual processing tools. In order to achieve optimum methods for the automatic treatment of more than one language, we propose the use of syntactic semantic patterns. These patterns are formed by a verbal head and the main arguments, and they are aligned among languages. In this paper we present an automatic system for the extraction and alignment of syntactic semantic patterns from two manually annotated corpora, and evaluate the main linguistic problems that we must deal with in the alignment process.

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Tese de mestrado, Geologia Aplicada (Hidrogeologia) Universidade de Lisboa, Faculdade de Ciências, 2016

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Due to the great challenges encountered in drilling wells, there is a need to develop fluids with appropriated properties and able to meet all the requirements of drilling operations. The physicochemical and rheological properties must be carefully controlled so that a fluid can exercise all its functions. In perforations sensitive to contact with water and "offshore", it becomes necessary the use of oil based drilling fluids, but the bentonite clay cannot be used without a previous surface modification so that their surfaces become hydrophobic. Lately, the oil companies in Brazil use imported organoclays in the preparation of oil-based drilling fluids. The study aimed to modify a calcium clay to increase the affinity of the same organic phase of oil-based drilling fluids, applying three surfactants (OCS, CTAB and UTM 150) at different concentrations. The results indicated that the surfactants UTM 150 and CTAB showed better results compared to OCS. Considering the type of surfactant and concentration as variables used in the statistical analysis, the results indicated that only the surface tension and concentration of calcium oxide in response to organophilization process showed statistically significant effects. The organophilizated clay has potential for application in oil-based drilling fluids.

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The Atlantic Advisory Panel proposed that Site 9 should be drilled on the northeastern flank of the Bermuda Rise (lat. 32° 37' N., long. 59° 10' W.), which is about 100 miles west of the Sohm Abyssal Plain. The bottom of this region consists of low linear ridges that are roughly parallel and oriented in a northwest-southeasterly direction. Scattered seamounts, some of which have peaks 2000 fathoms (3660 meters) below sea level, arise from the otherwise featureless sea floor between the ridges. The primary purpose in drilling Site 9 was to examine a sedimentary column where seismic reflectors were largely absent and to determine the age of sediments overlying acoustical basement in the examination of sea floor spreading.

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In May 1964 the Institute of Marine Science (University of Miami), Scripps Institution of Oceanography (University of California), Woods Hole Oceanographic Institution, and Lamont Geological Observatory (Columbia University) joined in the establishment of the JOINT OCEANOGRAPHIC INSTITUTIONS DEEP EARTH SAMPLING (JOIDES) program. The long range purpose of this organization is to obtain continuous core samples of the entire sedimentary column from the floors of the oceans. It was decided that initial efforts would be limited to water depths of less than 1000 fathoms (6000 feet), and tentative locations were selected for drilling operations off the eastern, western and Gulf coasts of the United States. Near the end of December 1964 it was found that the M/V Caldrill I, a drilling vessel capable of working to depths of 6000 feet, was to engage in drilling operations on the Grand Banks of Newfoundland during the summer of 1965 for the Pan American Petroleum Corporation. Thus it was agreed to organize a drilling program along the track of Caldrill between California and the Grand Banks. Selection was made of an area on the continental shelf and the Blake Plateau off Jacksonville, Florida. Based upon many previous geological and geophysical investigations by the participating laboratories, a considerable body of knowledge had been gained about this region of the continental-oceanic border. For this initial program of JOIDES, the Lamont Geological Observatory was chosen as the operating institution with J. L. Worzel as principal investigator, and C. L. Drake and H. A. Gibbon as program planners.

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The present paper describes a system for the construction of visual maps ("mosaics") and motion estimation for a set of AUVs (Autonomous Underwater Vehicles). Robots are equipped with down-looking camera which is used to estimate their motion with respect to the seafloor and built an online mosaic. As the mosaic increases in size, a systematic bias is introduced in its alignment, resulting in an erroneous output. The theoretical concepts associated with the use of an Augmented State Kalman Filter (ASKF) were applied to optimally estimate both visual map and the fleet position.

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Drilling fluids present a thixotropic behavior and they usually gel when at rest. The sol-gel transition is fundamental to prevent the deposit of rock fragments, generated by drilling the well, over the drill bit during eventual stops. Under those conditions, high pressures are then required in order to break-up the gel when circulation is resumed. Moreover, very high pressures can damage the rock formation at the bottom of the well. Thus, a better understanding of thixotropy and the behavior of thixotropic materials becomes increasingly important for process control. The mechanisms that control thixotropy are not yet well defined and modeling is still a challenge. The objective of this work is to develop a mathematical model to study the pressure transmission in drilling fluids. This work presents a review of thixotropy and of different mathematical models found in the literature that are used to predict such characteristic. It also shows a review of transient flows of compressible fluids. The problem is modeled as the flow between the drillpipe and the annular region (space between the wall and the external part of the drillpipe). The equations that describe the problem (mass conservation, momentum balance, constitutive and state) are then discretized and numerically solved by using a computational algorithm in Fortran. The model is validated with experimental and numerical data obtained from the literature. Comparisons between experimental data obtained from Petrobras and calculated by three viscoplastic and one pseudoplastic models are conducted. The viscoplastic fluids, due to the yield stress, do not fully transmit the pressure to the outlet of the annular space. Sensibility analyses are then conducted in order to evaluate the thixotropic effect in pressure transmission.

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Background: Among other causes the long-term result of hip prostheses in dogs is determined by aseptic loosening. A prevention of prosthesis complications can be achieved by an optimization of the tribological system which finally results in improved implant duration. In this context a computerized model for the calculation of hip joint loadings during different motions would be of benefit. In a first step in the development of such an inverse dynamic multi-body simulation (MBS-) model we here present the setup of a canine hind limb model applicable for the calculation of ground reaction forces. Methods: The anatomical geometries of the MBS-model have been established using computer tomography- (CT-) and magnetic resonance imaging- (MRI-) data. The CT-data were collected from the pelvis, femora, tibiae and pads of a mixed-breed adult dog. Geometric information about 22 muscles of the pelvic extremity of 4 mixed-breed adult dogs was determined using MRI. Kinematic and kinetic data obtained by motion analysis of a clinically healthy dog during a gait cycle (1 m/s) on an instrumented treadmill were used to drive the model in the multi-body simulation. Results and Discussion: As a result the vertical ground reaction forces (z-direction) calculated by the MBS-system show a maximum deviation of 1.75%BW for the left and 4.65%BW for the right hind limb from the treadmill measurements. The calculated peak ground reaction forces in z- and y-direction were found to be comparable to the treadmill measurements, whereas the curve characteristics of the forces in y-direction were not in complete alignment. Conclusion: In conclusion, it could be demonstrated that the developed MBS-model is suitable for simulating ground reaction forces of dogs during walking. In forthcoming investigations the model will be developed further for the calculation of forces and moments acting on the hip joint during different movements, which can be of help in context with the in silico development and testing of hip prostheses.

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Aligned nanofiber mats were prepared from cellulose acetate using an electrospinning technique. The nanofiber mats were then immersed in an ethanol/acetone mixture. The solvent treatment led to denser, more compact fibrous structure and slight decrease in fiber alignment. It increased fiber diameter and polymer crystallinity within fibers. These effects resulted in increase in the tensile strength of fibrous mats. Solvent treatment may offer a simple, efficient approach to improve the mechanical strength of nanofibrous mats.

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Depuis les débuts de la deuxième vague féministe, la participation quasi-universelle des femmes au marché du travail a causé la perte, pour les pères de famille, du rôle de pourvoyeur exclusif que ces derniers avaient tenu depuis si longtemps. Les femmes hétérosexuelles de la société contemporaine sont dorénavant plus scolarisées et atteignent des carrières plus avancées que leurs contreparties masculines. Alors que les femmes soutiennent davantage la famille par leurs emplois, les hommes doivent proportionnellement assumer des rôles plus actifs et participatifs à la maison. En cette période de transition, de transformation et de redéfinition rapides des rôles genrés à l’intérieur de l’économie familiale hétérosexuelle, les pères participent de manière plus équitable à l’éducation des enfants et à l’entretien du domicile, ces rôles ayant longtemps été attribués presque exclusivement aux femmes. Ces nouvelles responsabilités détonnent avec les représentations stéréotypées des hommes dans la culture populaire, ainsi qu’avec les modèles d’identification de la masculinité normative que les hommes ont requis et requièrent toujours sous l’égide de l’hétérosexualité imposée. De ce fait, les hommes occidentaux de moins de cinquante ans se trouvent souvent à cheval entre deux mondes d’exigences concurrentes. La place que peuvent et doivent prendre les pères au sein de leurs familles requiert un questionnement critique. L’ironie de la place du père peut être comprise comme la tension entre les normes du genre rétrogrades ou conservatrices et les exigences – à la fois politiques et pragmatiques – de la masculinité de la classe moyenne contemporaine. Cette tension fondamentale et structurante de la masculinité contemporaine est vécue par l’anxiété d’association au genre, ainsi qu’à travers des difficultés filiales, paternelles et intergénérationnelles. Ce mémoire de maîtrise adopte une approche déconstructiviste envers l’analyse de constructions contemporaines de la masculinité reproductive. À travers les gender studies, la théorie queer ainsi que la psychanalyse, le mémoire offre des lectures analytiques du discours de croissance personnelle de John Stoltenberg, de la fiction autobiographique de Karl Ove Knausgaard, ainsi que de la série télévisée américaine Dexter.

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High voltage electrophoretic deposition (HVEPD) has been developed as a novel technique to obtain vertically aligned forests of one-dimensional nanomaterials for efficient energy storage. The ability to control and manipulate nanomaterials is critical for their effective usage in a variety of applications. Oriented structures of one-dimensional nanomaterials provide a unique opportunity to take full advantage of their excellent mechanical and electrochemical properties. However, it is still a significant challenge to obtain such oriented structures with great process flexibility, ease of processing under mild conditions and the capability to scale up, especially in context of efficient device fabrication and system packaging. This work presents HVEPD as a simple, versatile and generic technique to obtain vertically aligned forests of different one-dimensional nanomaterials on flexible, transparent and scalable substrates. Improvements on material chemistry and reduction of contact resistance have enabled the fabrication of high power supercapacitor electrodes using the HVEPD method. The investigations have also paved the way for further enhancements of performance by employing hybrid material systems and AC/DC pulsed deposition. Multi-walled carbon nanotubes (MWCNTs) were used as the starting material to demonstrate the HVEPD technique. A comprehensive study of the key parameters was conducted to better understand the working mechanism of the HVEPD process. It has been confirmed that HVEPD was enabled by three key factors: high deposition voltage for alignment, low dispersion concentration to avoid aggregation and simultaneous formation of holding layer by electrodeposition for reinforcement of nanoforests. A set of suitable parameters were found to obtain vertically aligned forests of MWCNTs. Compared with their randomly oriented counterparts, the aligned MWCNT forests showed better electrochemical performance, lower electrical resistance and a capability to achieve superhydrophpbicity, indicating their potential in a broad range of applications. The versatile and generic nature of the HVEPD process has been demonstrated by achieving deposition on flexible and transparent substrates, as well as aligned forests of manganese dioxide (MnO2) nanorods. A continuous roll-printing HVEPD approach was then developed to obtain aligned MWCNT forest with low contact resistance on large, flexible substrates. Such large-scale electrodes showed no deterioration in electrochemical performance and paved the way for practical device fabrication. The effect of a holding layer on the contact resistance between aligned MWCNT forests and the substrate was studied to improve electrochemical performance of such electrodes. It was found that a suitable precursor salt like nickel chloride could be used to achieve a conductive holding layer which helped to significantly reduce the contact resistance. This in turn enhanced the electrochemical performance of the electrodes. High-power scalable redox capacitors were then prepared using HVEPD. Very high power/energy densities and excellent cyclability have been achieved by synergistically combining hydrothermally synthesized, highly crystalline α-MnO2 nanorods, vertically aligned forests and reduced contact resistance. To further improve the performance, hybrid electrodes have been prepared in the form of vertically aligned forest of MWCNTs with branches of α-MnO2 nanorods on them. Large- scale electrodes with such hybrid structures were manufactured using continuous HVEPD and characterized, showing further improved power and energy densities. The alignment quality and density of MWCNT forests were also improved by using an AC/DC pulsed deposition technique. In this case, AC voltage was first used to align the MWCNTs, followed by immediate DC voltage to deposit the aligned MWCNTs along with the conductive holding layer. Decoupling of alignment from deposition was proven to result in better alignment quality and higher electrochemical performance.

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Depuis les débuts de la deuxième vague féministe, la participation quasi-universelle des femmes au marché du travail a causé la perte, pour les pères de famille, du rôle de pourvoyeur exclusif que ces derniers avaient tenu depuis si longtemps. Les femmes hétérosexuelles de la société contemporaine sont dorénavant plus scolarisées et atteignent des carrières plus avancées que leurs contreparties masculines. Alors que les femmes soutiennent davantage la famille par leurs emplois, les hommes doivent proportionnellement assumer des rôles plus actifs et participatifs à la maison. En cette période de transition, de transformation et de redéfinition rapides des rôles genrés à l’intérieur de l’économie familiale hétérosexuelle, les pères participent de manière plus équitable à l’éducation des enfants et à l’entretien du domicile, ces rôles ayant longtemps été attribués presque exclusivement aux femmes. Ces nouvelles responsabilités détonnent avec les représentations stéréotypées des hommes dans la culture populaire, ainsi qu’avec les modèles d’identification de la masculinité normative que les hommes ont requis et requièrent toujours sous l’égide de l’hétérosexualité imposée. De ce fait, les hommes occidentaux de moins de cinquante ans se trouvent souvent à cheval entre deux mondes d’exigences concurrentes. La place que peuvent et doivent prendre les pères au sein de leurs familles requiert un questionnement critique. L’ironie de la place du père peut être comprise comme la tension entre les normes du genre rétrogrades ou conservatrices et les exigences – à la fois politiques et pragmatiques – de la masculinité de la classe moyenne contemporaine. Cette tension fondamentale et structurante de la masculinité contemporaine est vécue par l’anxiété d’association au genre, ainsi qu’à travers des difficultés filiales, paternelles et intergénérationnelles. Ce mémoire de maîtrise adopte une approche déconstructiviste envers l’analyse de constructions contemporaines de la masculinité reproductive. À travers les gender studies, la théorie queer ainsi que la psychanalyse, le mémoire offre des lectures analytiques du discours de croissance personnelle de John Stoltenberg, de la fiction autobiographique de Karl Ove Knausgaard, ainsi que de la série télévisée américaine Dexter.

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Num contexto empresarial globalizado, a gestão de recursos humanos assume importância crescente. A valorização do capital humano e a preocupação com o compromisso e produtividade das pessoas revelam-se imperativos para a gestão de recursos humanos na contemporaneidade. As políticas e práticas de recursos humanos revelam-se a forma mais eficaz de comprometer as pessoas e, consequentemente, melhorar a performance organizacional. Este trabalho final de mestrado resultou de um estágio realizado num agrupamento complementar de empresa da IBM. Além das actividades desenvolvidas em contexto organizacional, efectuou-se urna descrição de todo o processo de gestão de recursos humanos e analisou-se a relação entre as políticas e práticas de recursos humanos e o compromisso organizacional, nas suas diferentes dimensões. Os resultados deste diagnóstico revelam que os colaboradores apresentam índices elevados de compromisso organizacional para com o ACE. Este compromisso materializa-se no alinhamento dos objectivos de negócio com os objectivos dos colaboradores. A principal causa destes índices elevados de compromisso são as políticas e práticas de recursos humanos. ABSTRACT: ln a globalized business environment, HRM assumes increasing importance. The human capital and concern for the commitment and productivity of people tum out to be imperative for the contemporary human resource management. Policies and practices of human resources prove to be the most effective way to engage people and thus improve organizational performance. This scientific work resulted from one stage held in a complementary group of the IBM Company. Besides the activities in organizations, took place a description of the whole process of resource management and examined the relationship of policies and practices in human resources with organizational commitment, in its various levels. The results of this diagnosis show that employees have high levels of organizational commitment towards the ACE. This commitment is materialized in the alignment of business goals with employee objectives. The main cause of these high levels of commitment are the policies and practices of human resources.