165 resultados para Falhas ósseas


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Aim: To determine the frequency and type of complications related to removable partial denture (RPD) less, Kennedy Class I, over time . Materials and Methods: This observational study consisted of a sample of 65 users PPR lower arches in Kennedy Class I and dentures, rehabilitated in the Department of Dentistry, Federal University of Rio Grande do Norte (UFRN). Patients were followed through periodic controls during periods of 60 days, 6 months and 1 year from installation. After the first year of control had other returns annually. The occurrence of complications or prosthetic failure was observed and recorded in a specific clinical record over 39 months. The patterns of failures observed were classified in the following situations: occurrence of traumatic ulcers after 2 months of installation, lack of retention, fracture or caries in the rest, fracture or dislocation of the artificial teeth, the larger connector fracture, fracture clip fracture support, poor support (need to reline the denture) and prosthesis fracture. Results: The incidence of complications was low frequency, being higher in the second year of use of the prosthesis. Among the complications that occurred more is the loss of retention (31.57%). Failures more severe and difficult to solve as the fracture elements of the metal structure of the PPR had low occurrence and were represented by only one case of the larger connector (5.3%) fractures. Conclusion: Removable partial dentures mandibular free end opposing of the conventional dentures have a low complication rate after 39 months of use when subjected to periodic controls

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Web services are software units that allow access to one or more resources, supporting the deployment of business processes in the Web. They use well-defined interfaces, using web standard protocols, making possible the communication between entities implemented on different platforms. Due to these features, Web services can be integrated as services compositions to form more robust loose coupling applications. Web services are subject to failures, unwanted situations that may compromise the business process partially or completely. Failures can occur both in the design of compositions as in the execution of compositions. As a result, it is essential to create mechanisms to make the implementation of service compositions more robust and to treat failures. Specifically, we propose the support for fault recovery in service compositions described in PEWS language and executed on PEWS-AM, an graph reduction machine. To support recovery failure on PEWS-AM, we extend the PEWS language specification and adapted the rules of translation and reduction of graphs for this machine. These contributions were made both in the model of abstract machine as at the implementation level

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In this work, we propose a two-stage algorithm for real-time fault detection and identification of industrial plants. Our proposal is based on the analysis of selected features using recursive density estimation and a new evolving classifier algorithm. More specifically, the proposed approach for the detection stage is based on the concept of density in the data space, which is not the same as probability density function, but is a very useful measure for abnormality/outliers detection. This density can be expressed by a Cauchy function and can be calculated recursively, which makes it memory and computational power efficient and, therefore, suitable for on-line applications. The identification/diagnosis stage is based on a self-developing (evolving) fuzzy rule-based classifier system proposed in this work, called AutoClass. An important property of AutoClass is that it can start learning from scratch". Not only do the fuzzy rules not need to be prespecified, but neither do the number of classes for AutoClass (the number may grow, with new class labels being added by the on-line learning process), in a fully unsupervised manner. In the event that an initial rule base exists, AutoClass can evolve/develop it further based on the newly arrived faulty state data. In order to validate our proposal, we present experimental results from a level control didactic process, where control and error signals are used as features for the fault detection and identification systems, but the approach is generic and the number of features can be significant due to the computationally lean methodology, since covariance or more complex calculations, as well as storage of old data, are not required. The obtained results are significantly better than the traditional approaches used for comparison

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The region of the Senador Pompeu Shear Zone (SPSZ), in the North Tectonic Domain of the Borborema Province (BP), has its recent history associated with to South Atlantic Ocean formation event at the Jurassic. A lot of geologics models have discussed about crustal axis elevation in local scale and large scale (Borborema Province), relative to importants regionals tectonics directions of it. The identification and the relationship among this surfaces, stepped in many topographyc levels by tectonics mecanisms, is dificult because of the erosion process on it. Over there, sedimentary deposits is complex and it has not biostratigraphyc record in continental deposits. The analysis metodology on apatita fission-track, in the region of the SPSZ, purpose the more knowledge about morphotectonics mecanisms of the area and the impruvement of its morphotectonics models. For this, it was moleled the age and thermal history of the 11 apatites samples collected on both sides of this shear zone, taking relationships among other results of the thermochronology studies in the BP. Based on the thermal studies in this search, the region of the BP developed on two distint cooling events, separated for one period of relative stabilited. The first episode occur between 130 and 90 M.y., has been began when the samples cross the 120°C isoterm for last time and fineshed at 70°C. The second moment of the cooling process was began about 30 M.y., when the temperature was 90°C, from this to the equlibrium with present surface temperature at 30°C. Some evidences indicated a relacionship between thermal episodes and uplift events of the regional relief. The fundaments of the interpretation was based mainly on comparatives studies among results of the thermochronology analysis and geologics studies about BP. Nóbrega et al.(2005), e.g., on studies about the Portalegre Shear Zone, got similar results on SPSZ, with some details relative to local tectonic activity. Morais Neto et al. (2000) interpreted two importants cooling events in the BP based on their regional studies, that can be associated to regional uplift events. When Assine (1992) studied the stratigraphyc sequences of the Araripe Basin, in the south of Ceará state, conclude that the abrupt return to continentals condictions from the last sedimentar sequency (albiano-cenomaniane) indicate a regional uplift of the NE region of the Brazil at the 100 M.y., in the Albiano Intermediate/Superior. This ages are compatible to termal model of the SPSZ. This two periods of the thermal history of the BP are completely registered in the apatites samples just one age groups of the fission-track, that it is the most ancient age groups. This one suggest it has happened in response to heating before 75 M.y and it has erased the last report of the first moment relief evolution of the BP. The NNE-SSW and E-W structure reativation can have created ideal condictions for heating and local elevations of the geothermal gradients. The equilibrium between the apatites temperatures of this groups and the regionais temperatures took place about 50 M.y., when the samples of the two ages groups had a simillar evolution to present surfaces temperatures

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior

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A research project is being developed by PPGG/UFRN and PETROBRAS in the Xaréu Oil Field located in Ceará Basin, Northeastern Brazil. The objective of the research is to characterize a fractured carbonate reservoir, the Trairi Limestone, in order to drill a borehole with two horizontal legs taking advantage of the natural fracture system to enhance the oil recovery. The present master thesis is part of this research and its contribution is to estimate fault orientation from unoriented cores, using the method proposed by Hesthammer & Henden (2000). In order to orient a fault cutting a bed observed in the core, the bed should be previously oriented. As additional constraint to orient the bed, we use regional bedding orientation obtained from structure maps of Trairi Limestone. Because the number of cores drilled from the Trairi Limestone was too small, we analyzed all cores from the field. As geologic constraint, we admit that all faults were formed as result of the South America and Africa separation, in the context of a regional dextral strike-slip fault formation. In this context, secondary faults are manly T and R faults according Riedel s classification. We analyzed 236.5 m of cores. The dip of bedding varies from 0o to 8o, being the most frequent value equal to 2o. We interpret this result as evidence that the deformation process was manly ruptil. 77 faults were identified in the cores. These faults strike manly to NW and NE with dips, in general, inside the interval 700 - 900. We suggest that the horizontal legs of the borehole should be oriented to NW and NE in order to improve the probability of intercepting open fractures and faults

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The geological modeling allows, at laboratory scaling, the simulation of the geometric and kinematic evolution of geological structures. The importance of the knowledge of these structures grows when we consider their role in the creation of traps or conduits to oil and water. In the present work we simulated the formation of folds and faults in extensional environment, through physical and numerical modeling, using a sandbox apparatus and MOVE2010 software. The physical modeling of structures developed in the hangingwall of a listric fault, showed the formation of active and inactive axial zones. In consonance with the literature, we verified the formation of a rollover between these two axial zones. The crestal collapse of the anticline formed grabens, limited by secondary faults, perpendicular to the extension, with a curvilinear aspect. Adjacent to these faults we registered the formation of transversal folds, parallel to the extension, characterized by a syncline in the fault hangingwall. We also observed drag folds near the faults surfaces, these faults are parallel to the fault surface and presented an anticline in the footwall and a syncline hangingwall. To observe the influence of geometrical variations (dip and width) in the flat of a flat-ramp fault, we made two experimental series, being the first with the flat varying in dip and width and the second maintaining the flat variation in width but horizontal. These experiments developed secondary faults, perpendicular to the extension, that were grouped in three sets: i) antithetic faults with a curvilinear geometry and synthetic faults, with a more rectilinear geometry, both nucleated in the base of sedimentary pile. The normal antithetic faults can rotate, during the extension, presenting a pseudo-inverse kinematics. ii) Faults nucleated at the top of the sedimentary pile. The propagation of these faults is made through coalescence of segments, originating, sometimes, the formation of relay ramps. iii) Reverse faults, are nucleated in the flat-ramp interface. Comparing the two models we verified that the dip of the flat favors a differentiated nucleation of the faults at the two extremities of the mater fault. V These two flat-ramp models also generated an anticline-syncline pair, drag and transversal folds. The anticline was formed above the flat being sub-parallel to the master fault plane, while the syncline was formed in more distal areas of the fault. Due the geometrical variation of these two folds we can define three structural domains. Using the physical experiments as a template, we also made numerical modeling experiments, with flat-ramp faults presenting variation in the flat. Secondary antithetic, synthetic and reverse faults were generated in both models. The numerical modeling formed two folds, and anticline above the flat and a syncline further away of the master fault. The geometric variation of these two folds allowed the definition of three structural domains parallel to the extension. These data reinforce the physical models. The comparisons between natural data of a flat-ramp fault in the Potiguar basin with the data of physical and numerical simulations, showed that, in both cases, the variation of the geometry of the flat produces, variation in the hangingwall geometry

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The structural knowledge of the western portion of the Potiguar Basin is still in its infancy, especially these related to NW-trending fault systems. This paper analyzes the Poço Verde-Caraúbas Fault System, which was initially recognized in subsurface. The activities involved in this study correspond to remote-sensing analysis and, in particular, to the geometric and kinematic analysis of post-rift sequences of the basin. In addition, the study aimed to determine the stress fields operating in the area. The studies were carried out in an area of 1,000 km², located in the western portion of Potiguar Basin along the Poço Verde-Caraúbas Fault System, Rio Grande do Norte State. The remote sensing imagery indicates a predominance of NW-SE-trending lineaments, consistent with the fault system under study, followed by the NE-SW, N-S and E-W directions. The tectonic structures mapped were analyzed only in outcrops of the Jandaíra Formantion. They are joints (filled or not) in all directions, but with predominance of the NW-trending joints. Faults are usually N-S-trending normal faults and NW-SE and NE-SW-trending strike-slip faults. Geodynamic analysis identified two tectonic stress fields: the first field, "Field 1" is represented by an N-S-trending horizontal compression and E-W-trending horizontal extension. This field affected the Potiguar Basin at least until the Miocene. The second field, "Field 2", is represented by an E-W-trending horizontal compression and N-S-trending horizontal extension. This is the present-day stress field and has affected the Potiguar basin since the Pliocene

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The Baixa grande fault is located on the edge of the S-SW Potiguar Rift. It limits the south part of Umbuzeiro Graben and the Apodi Graben. Although a number of studies have associated the complex deformation styles in the hanging wall of the Baixa Grande Fault with geometry and displacement variations, none have applied the modern computational techniques such as geometrical and kinematic validations to address this problem. This work proposes a geometric analysis of the Baixa Fault using seismic interpretation. The interpretation was made on 3D seismic data of the Baixa Grande fault using the software OpendTect (dGB Earth Sciences). It was also used direct structural modeling, such as Analog Direct Modeling know as Folding Vectors and, 2D and 3D Direct Computational Modeling. The Folding Vectors Modeling presented great similarity with the conventional structural seismic interpretations of the Baixa Grande Fault, thus, the conventional interpretation was validated geometrically. The 2D direct computational modeling was made on some sections of the 3D data of the Baixa Grande Fault on software Move (Midland Valley Ltd) using the horizon modeling tool. The modeling confirms the influence of fault geometry on the hanging wall. The Baixa Grande Fault ramp-flat-ramp geometry generates synform on the concave segments of the fault and antiform in the convex segments. On the fault region that does not have segments angle change, the beds are dislocated without deformation, and on the listric faults occur rollover. On the direct 3D computational modeling, structural attributes were obtained as horizons on the hanging wall of the main fault, after the simulation of several levels of deformation along the fault. The occurrence of structures that indicates shortening in this modeling, also indicates that the antiforms on the Baixa Grande Fault were influenced by fault geometry

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The detection and diagnosis of faults, ie., find out how , where and why failures occur is an important area of study since man came to be replaced by machines. However, no technique studied to date can solve definitively the problem. Differences in dynamic systems, whether linear, nonlinear, variant or invariant in time, with physical or analytical redundancy, hamper research in order to obtain a unique solution . In this paper, a technique for fault detection and diagnosis (FDD) will be presented in dynamic systems using state observers in conjunction with other tools in order to create a hybrid FDD. A modified state observer is used to create a residue that allows also the detection and diagnosis of faults. A bank of faults signatures will be created using statistical tools and finally an approach using mean squared error ( MSE ) will assist in the study of the behavior of fault diagnosis even in the presence of noise . This methodology is then applied to an educational plant with coupled tanks and other with industrial instrumentation to validate the system.

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The continuous evolution of integrated circuit technology has allowed integrating thousands of transistors on a single chip. This is due to the miniaturization process, which reduces the diameter of wires and transistors. One drawback of this process is that the circuit becomes more fragile and susceptible to break, making the circuit more susceptible to permanent faults during the manufacturing process as well as during their lifetime. Coarse Grained Reconfigurable Architectures (CGRAs) have been used as an alternative to traditional architectures in an attempt to tolerate such faults due to its intrinsic hardware redundancy and high performance. This work proposes a fault tolerance mechanism in a CGRA in order to increase the architecture fault tolerance even considering a high fault rate. The proposed mechanism was added to the scheduler, which is the mechanism responsible for mapping instructions onto the architecture. The instruction mapping occurs at runtime, translating binary code without the need for recompilation. Furthermore, to allow faster implementation, instruction mapping is performed using a greedy module scheduling algorithm, which consists of a software pipeline technique for loop acceleration. The results show that, even with the proposed mechanism, the time for mapping instructions is still in order of microseconds. This result allows that instruction mapping process remains at runtime. In addition, a study was also carried out mapping scheduler rate. The results demonstrate that even at fault rates over 50% in functional units and interconnection components, the scheduler was able to map instructions onto the architecture in most of the tested applications.

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In the last decades, analogue modelling has been used in geology to improve the knowledge of how geological structures are nucleated, how they grow and what are the main important points in such processes. The use of this tool in the oil industry, to help seismic interpretations and mainly to search for structural traps contributed to disseminate the use of this tool in the literature. Nowadays, physical modelling has a large field of applications, since landslide to granite emplacement along shear zones. In this work, we deal with physical modelling to study the influence of mechanical stratifications in the nucleation and development of faults and fractures in a context of orthogonal and conjugated oblique basins. To simulate a mechanical stratigraphy we used different materials, with distinct physical proprieties, such as gypsum powder, glass beads, dry clay and quartz sand. Some experiments were run along with a PIV (Particle Image Velocimetry), an instrument that shows the movement of the particles to each deformation moment. Two series of experiments were studied: i) Series MO: We tested the development of normal faults in a context of an orthogonal (to the extension direction) basin. Experiments were run taking into account the change of materials and strata thickness. Some experiments were done with sintectonic sedimentation. We registered differences in the nucleation and growth of faults in layers with different rheological behavior. The gypsum powder layer behaves in a more competent mode, which generates a great number of high angle fractures. These fractures evolve to faults that exhibit a higher dip than when they cross less competent layers, like the one of quartz sand. This competent layer exhibits faulted blocks arranged in a typical domino-style. Cataclastic breccias developed along the faults affecting the competent layers and showed different evolutional history, depending on the deforming stratigraphic sequence; ii) Series MOS2: Normal faults were analyzed in conjugated sub-basins (oblique to the extension direction) developed in a sequence with and without rheological contrast. In experiments with rheological contrast, two important grabens developed along the faulted margins differing from the subbasins with mechanical stratigraphy. Both experiments developed oblique fault systems and, in the area of sub-basins intersection, faults traces became very curved.

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A Wireless Sensor Network (WSN) consists of distributed devices in an area in order to monitor physical variables such as temperature, pressure, vibration, motion and environmental conditions in places where wired networks would be difficult or impractical to implement, for example, industrial applications of difficult access, monitoring and control of oil wells on-shore or off-shore, monitoring of large areas of agricultural and animal farming, among others. To be viable, a WSN should have important requirements such as low cost, low latency, and especially low power consumption. However, to ensure these requirements, these networks suffer from limited resources, and eventually being used in hostile environments, leading to high failure rates, such as segmented routing, mes sage loss, reducing efficiency, and compromising the entire network, inclusive. This work aims to present the FTE-LEACH, a fault tolerant and energy efficient routing protocol that maintains efficiency in communication and dissemination of data.This protocol was developed based on the IEEE 802.15.4 standard and suitable for industrial networks with limited energy resources

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The discussion about rift evolution in the Brazilian Equatorial margin during the South America-Africa breakup in the Jurassic/Cretaceous has been focused in many researches. But rift evolution based on development and growth of faults has not been well explored. In this sense, we investigated the Cretaceous Potiguar Basin in the Equatorial margin of Brazil to understand the geometry of major faults and the influence of crustal heterogeneity and preexisting structural fabric in the evolution of the basin internal architecture. Previous studies pointed out that the rift is an asymmetrical half-graben elongated along the NE-SW direction. We used 2D seismic, well logs and 3D gravity modeling to analyze four major border fault segments and determine their maximum displacement (Dmax) and length (L) ratio in the Potiguar Rift. We constrained the 3D gravity modeling with well data and the interpretation of seismic sections. The difference of the fault displacement measured in the gravity model is in the order of 10% compared to seismic and well data. The fault-growth curves allowed us to divide the faulted rift border into four main fault segments, which provide roughly similar Dmax/L ratios. Fault-growth curves suggest that a regional uniform tectonic mechanism influenced growth of the rift fault segments. The variation of the displacements along the fault segments indicates that the fault segments were formed independently during rift initiation and were linked by hard and soft linkages. The latter formed relay ramps. In the interconnection zones the Dmax/L ratios are highest due to interference of fault segment motions. We divided the evolution of the Potiguar Rift into five stages based on these ratios and correlated them with the major tectonic stages of the breakup between South America and Africa in Early Cretaceous.

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The discussion about rift evolution in the Brazilian Equatorial margin during the South America-Africa breakup in the Jurassic/Cretaceous has been focused in many researches. But rift evolution based on development and growth of faults has not been well explored. In this sense, we investigated the Cretaceous Potiguar Basin in the Equatorial margin of Brazil to understand the geometry of major faults and the influence of crustal heterogeneity and preexisting structural fabric in the evolution of the basin internal architecture. Previous studies pointed out that the rift is an asymmetrical half-graben elongated along the NE-SW direction. We used 2D seismic, well logs and 3D gravity modeling to analyze four major border fault segments and determine their maximum displacement (Dmax) and length (L) ratio in the Potiguar Rift. We constrained the 3D gravity modeling with well data and the interpretation of seismic sections. The difference of the fault displacement measured in the gravity model is in the order of 10% compared to seismic and well data. The fault-growth curves allowed us to divide the faulted rift border into four main fault segments, which provide roughly similar Dmax/L ratios. Fault-growth curves suggest that a regional uniform tectonic mechanism influenced growth of the rift fault segments. The variation of the displacements along the fault segments indicates that the fault segments were formed independently during rift initiation and were linked by hard and soft linkages. The latter formed relay ramps. In the interconnection zones the Dmax/L ratios are highest due to interference of fault segment motions. We divided the evolution of the Potiguar Rift into five stages based on these ratios and correlated them with the major tectonic stages of the breakup between South America and Africa in Early Cretaceous.