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Our research focuses on refining the ability to discriminate two petrogenic oil-slick categories: the sea surface expression of naturally-occurring oil seeps and man-made oil spills. For that, a long-term RADARSAT-2 dataset (244 scenes imaged between 2008 and 2012) is analyzed to investigate oil slicks (4562) observed in the Gulf of Mexico (Campeche Bay, Mexico). As the scientific literature on the use of satellite-derived measurements to discriminate the oil-slick category is sparse, our research addresses this gap by extending our previous investigations aimed at discriminating seeps from spills. To reveal hidden traits of the available satellite information and to evaluate an existing Oil-Slick Discrimination Algorithm, distinct processing segments methodically inspect the data at several levels: input data repository, data transformation, attribute selection, and multivariate data analysis. Different attribute selection strategies similarly excel at the seep-spill differentiation. The combination of different Oil-Slick Information Descriptors presents comparable discrimination accuracies. Among 8 non-linear transformations, the Logarithm and Cube Root normalizations disclose the most effective discrimination power of almost 70%. Our refined analysis corroborates and consolidates our earlier findings, providing a firmer basis and useful accuracies of the seep-spill discrimination practice using information acquired with space-borne surveillance systems based on Synthetic Aperture Radars.

The aim of this work is to investigate the behavior of volume transport and advective heat flux patterns which are related to the Brazil Current System (BCS) according to the climate change scenarios suggested by the Intergovernmental Panel on Climate Changes. The results deriving from the global model Climate Model version 2.1 (GFDL-CM2.1) for future scenarios of climate change A1FI and B1 and for the scenario that represents the climate in the Twentieth Century (20C3M) have been used in this work. Volume transport and advective heat flux integrated for the whole BCS as well as for each water mass which constitutes the system have been calculated applying these data. Estimates were made for three zonal sections (23ºS, 25ºS and 30ºS) and then were used in the Wavelet Analysis. The performed analysis showed the occurrence of interannual variability for the estimated properties in the region. It also showed that the BCS shows changes in both intensity and variability of these parameters when comparing A1FI and B1 to 20C3M. Results from Wavelet Analysis for the total volume transport and advective heat flux integrated per section show that the period between three and six years prevails in sections 23ºS and 25ºS. The variability in 30ºS however, is significantly higher than eight years. It could also be observed the change of the variability of the total volume transport and heat flux temporal series towards higher frequencies when they are submitted to A1FI and B1 climate changes scenarios.

Campeche Bay, located in the Gulf of Mexico, is a well-established fossil fuel producing region, with numerous oil rigs exploring oil and natural gas. In an effort to reduce negative impacts on marine ecosystems, Pemex continuously monitored Campeche Bay for oil slicks, i.e., naturally occurring oil seeps and manmade oil spills. A long-term dataset (2000–2012) of synthetic aperture radar measurements from both RADARSAT satellites (766) is leveraged to investigate the spatial-temporal distribution of oil slicks (14,210) in this region. The present study has a threefold goal: (1) describe the monitoring strategy completed by Pemex and the information produced during such monitoring; (2) investigate the spatial-temporal distribution of the oil slicks observed in Campeche Bay, centering on aspects related to their occurrence; and (3) demonstrate the usefulness of RADARSAT-derived information in the execution of effective long-term environmental applications to locate seeps and spills on the sea surf...

Aiming to achieve systematic ocean forecasting for the southeastern Brazilian coast, an incremental 4D-Var data assimilation system is applied to a regional ocean model focused mainly in the Santos Basin region. This implementation is performed within the scope of The Santos Basin Ocean Observing System (or Project Azul), a pilot project designed to collect oceanographic data with enough frequency and spatial coverage so to improve regional forecasts through data assimilation. The ocean modeling and data assimilation system of Project Azul is performed with the Regional Ocean Modeling System (ROMS). The observations used in the assimilation cycles include the following: 1-day gridded, 0.1° resolution SST from POES AVHRR; 1-day gridded, 0.3° composite of the MDT SSH from AVISO; and surface and subsurface hydrographic measurements of temperature and salinity collected with gliders and ARGO floats from Project Azul and from UK Met-Office EN3 project dataset. The assimilative model results are compared to forward model results and independent observations, both from remote sensing and in situ sources. The results clearly show that 4D-Var data assimilation leads to an improvement in the skill of ocean hindcast in the studied region.

The purpose of this study is to evaluate the main aspects of the mesoscale ocean circulation of the Brazilian Equatorial Margin using a ten-year hydrodynamic hindcast that successfully represented in situ and satellite observational data. The seasonality and distribution of the Amazon River Plume (ARP), as well as the volume transport of the North Brazil Current (NBC) in two cross-current sections were described. The results indicate the NBC influences on the shape and spread of the ARP, and the relationship between the seasonal behavior of the Inter-tropical Convergence Zone migration, of the wind stress curl, and of the northern branch of the South Equatorial Current with the NBC pattern.

The spatial and temporal variability of energy exchange in Tropical Instability Waves (TIWs) in the Atlantic Ocean were investigated. A spectral analysis was used to filter the 5-day mean results from Simple Ocean Data Assimilation reanalysis spanning from 1958 to 2008. TIWs were filtered over periods of 15 to 60 days and between wavelengths of 4 and 20 longitude degrees. The main approach of this study was the use of bidirectionally filtered TIW time series as the perturbation fields, and the difference in these time series from the SODA total results was considered to be the basic state for energetics analysis. The main result was that the annual cycle (period of ~ 360 days) was the main source of variability of the waves, and the semi-annual cycle (period of ~ 180 days) was a secondary variation, which indicated that TIWs occurred throughout the year but with intensity that varies seasonally. Barotropic instability acts as the mechanism that feeds and extracts energy to/from TIWs as alternate zonal bands at equatorial Atlantic. Baroclinic instability is the main mechanism that extracts energy from TIWs to the equatorial circulation north of Equator. All TIW patterns of variability were observed at west of ~ 10º W. The present study reveals new evidences regarding TIW variability and suggests that future investigations should include a detailed description of TIW dynamics as part of Atlantic Ocean equatorial circulation

An Exploratory Data Analysis (EDA) aims to use Synthetic Aperture Radar (SAR) measurements for discriminating between two oil slick types observed on the sea surface: naturally-occurring oil seeps versus human-related oil spills—the use of satellite sensors for this task is poorly documented in scientific literature. A long-term RADARSAT dataset (2008–2012) is exploited to investigate oil slicks in Campeche Bay (Gulf of Mexico). Simple Classification Algorithms to distinguish the oil slick type are designed based on standard multivariate data analysis techniques. Various attributes of geometry, shape, and dimension that describe the oil slick Size Information are combined with SAR-derived backscatter coefficients—sigma-(σo), beta-(βo), and gamma-(γo) naught. The combination of several of these characteristics is capable of distinguishing the oil slick type with ~70% of overall accuracy, however, the sole and simple use of two specific oil slick’s Size Information (i.e., area and perimeter) is equally capable of distinguishing seeps from spills. The data mining exercise of our EDA promotes a novel idea bridging petroleum pollution and remote sensing research, thus paving the way to further investigate the satellite synoptic view to express geophysical differences between seeped and spilled oil observed on the sea surface for systematic use.

The knowledge of wind stress variability could represent an important contribution to understand the variability over upper layer ocean volume transports. The South Brazilian Bight (SBB) circulation had been studied by numerous researchers who predominantly attempted to estimate its meridional volume transport. The main objective and contribution of this study is to identify and quantify possible interannual variability in the ocean volume transport in the SBB induced by the sea surface wind stress field. A low resolution ocean global circulation model was implemented to investigate the volume transport variability. The results obtained indicate the occurrence of interannual variability in meridional ocean volume transports along three different zonal sections. These results also indicate the influence of a wind driven large-scale atmospheric process that alters locally the SBB and near-offshore region wind stress field and consequently causes interannual variability in the upper layer ocean volume transports. A strengthening of the southward flow in 25°S and 30°S was observed. The deep layer ocean volume transport in the three monitored sections indicates a potential dominance of other remote ocean processes. A small time lag between the integrated meridional volume transports changes in each monitored zonal section was observed.

In this paper, it is presented the results using Reverse Time Migration (RTM) technique for different formulations of the full waveform equations with the aim to evaluate the migrated sections accuracy. RTM based on acoustic isotropic wave equation (Isotropic RTM), RTM based on pseudo-acoustic vertical transversely wave equation (VTI RTM) and RTM based on pseudo-acoustic tilted transversely isotropic wave equation (TTI RTM) were implemented. These algorithms were used to migrate the Benchmark 2D BP 2007 TTI dataset and to build the Common Image Gathers (CIGs). CIGs will allow the analysis of the anisotropy parameters influence in migrated sections.

The Amazon is a region characterized by ecologically complex environments subject to constant and rapid seasonal changes. In Central Amazonia, the seasonal differences in water level caused by flooding changes the landscape and require the production of one sensitivity maps for each season: dry, full ebb and flow. Potential applications of the the Synthetic Aperture Radar (SAR) system on board the JERS-1 satellite for environmental protection in Amazonia include understanding and management of flood hazards. This presents a methodology to compute a multitemporal environmental sensitivity to oil spill map in regional scale, according to the change in flooding conditions. The differences of image patterns from low flow to high flow derives the classes of change, which represent the types of landscape change within half hydrological cycle. A fuzzy system is implemented within a geographic information system (GIS) to map oil-sensitive environments for environmental risk assessment along the Solimoes River oil transportation route, Western Amazonia, Brazil.

Accidents in nuclear power plants are problems of great complexity, mainly due to their consequences, such as the population evacuation from the enterprise influence area. The decision-making and emergency plans must be well articulated and require good local geographic space knowledge and the interactions of their environments. This study is a contribution to the emergency plans for the Almirante Alvaro Alberto Nuclear Power Plant, currently the only nuclear complex in Brazil, located in Angra dos Reis, Rio de Janeiro. The study confirmed the region’s main geoenvironmental aspects as winds and rainfall, landslides and population density were evaluated as important elements in the local emergency process. Their integrated analysis supported scenario identification and critical regional points and highlighted population evacuation escape routes. These important results characterized the support to local emergency management actions and guidelines. Furthermore, the geographic information systems was configured as an integrated spatial and temporal analysis platform to associate meteorological, geological/geomorphological and socio-economic data, playing a key role to support the evacuation planning in the event of nuclear power plant accidents.

Submitted by Jairo Amaro (jairo.amaro@sibi.ufrj.br) on 2019-06-26T18:12:04Z No. of bitstreams: 1 2013_SILVA_v5_p13-23-min.pdf: 732896 bytes, checksum: 87d048232c48dfe9a2eba58b93fd84e1 (MD5) Made available in DSpace on 2019-06-26T18:12:04Z (GMT). No. of bitstreams: 1 2013_SILVA_v5_p13-23-min.pdf: 732896 bytes, checksum: 87d048232c48dfe9a2eba58b93fd84e1 (MD5) Previous issue date: 2013-01-07 Indisponível. The outlook concerning the occurrence of industrial accidents has led to the implementation of response systems based on geoprocessing tools, which are widely adopted in emergency for such ventures, since they have helped and served as a support for decision making, as well as for the preparation of guidelines aimed at managing emergencies. Nuclear power plants, because they constitute types of industrial activities that present dangerous conditions and attention regarding security are characterized as hazardous, especially due to consequences that occurred from large accidents— such as Chernobyl (1986) and Fukushima (2011)—highlighting the importance to its negative impacts, since the occurrence of accidents at nuclear power plants may affect surrounding areas, thus exposing a set of elements that are part of the environmental dynamics that integrates the catchment area where this type of plant is situated. In this way, through an integrated view of the region where the nuclear complex is located in Angra dos Reis City (Rio de Janeiro State) and, also, by aggregating information that portray the geobiophysical reality of its surroundings, several elements were incorporated into a database developed in a virtual environment, in which was produced a geographic information system (GIS) that presents a complex of variables that, once considered, can enhance various analysis in order to support emergency situations and planning, as well as guidelines that help define actions from the occurrence of accidental events at the nuclear plant.

This study focuses on the surroundings of the Urucu oil and gas province and the adjoining Solimoes terminal in the Amazon region of Brazil, which is of great global importance due to its biodiversity richness and freshwater resources. There are few results related to aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (PAHs), and there are no results for individual stable isotopic compositions (δ13C) in the studied region. Results showed a distribution of n-alkanes that is characteristic of a major input from higher plants. Furthermore, δ13C values of individual n-alkanes varied between −35.0 and −23.1 ‰, suggesting a dominance of 12C-enriched n-alkanes indicative of an origin from lacustrine algae. The levels of some PAHs (4.64–31.70 ng g−1) which are classified as priority pollutants by the United States Environmental Protection Agency (US-EPA) and perylene (biogenic PAH) were measured in surface sediments to identify pollution sources and determine baseline data looking for future management strategies. The majority of the compounds present in the samples from Coari Lake and the Solimoes River are of biogenic origin. However, a minor anthropogenic contribution of aromatic hydrocarbons derived from biomass burning (anthracene, phenanthrene, fluoranthene, pyrene, chrysene, benzo[b]fluoranthene and benzo[k]fluoranthene) was detected. No petrogenic contribution was found in the samples.

New challenges and demands on software engineering education are presented by rapid changes and increased complexity of software systems. This paper presents the VisAr3D environment that has been developed as an innovative proposal to be introduced in the classroom to provide a 3D visualization of UML models. The user is invited to intuitively understand the model elements in this 3D environment. It includes exploration and interaction to establish a practical and pleasant learning activity focusing on large scale systems. It provides a new way to visualize and understand UML models by combining the technologies of Virtual Reality and Augmented Reality. A 3D diagram is automatically generated from an existing 2D diagram and is able to provide richer semantics than its corresponding 2D diagram. The paper also presents some results of an experimental study conducted to investigate the feasibility of using the approach. The evaluation has provided positive evidence of its ability to improve the understanding of UML models in systems with many modeling elements. And also shows the contribution of the insertion of the third dimension on this understanding, in the interests of the students and in support to the practice of teaching.

This paper reports recent results achieved in a research and development (R&D) with non-conventional interfaces for human-system interaction in nuclear plants' virtual simulations. This R&D aims at developing applications based on virtual reality technology for simulations toward training, ergonomics evaluation, safety and security purposes in the nuclear engineering field. Two main applications are under development, one comprising a virtual control desk (VCD) for users' interaction with a computer-based nuclear power plant (NPP) simulator, and the other comprising multi-user navigation in virtual environments which in turn correspond to nuclear plants and other sites. Non-conventional interfaces mean more friendly and natural human-system interfaces, compared to computer keyboard and mouse, as speech-based command recognition and face tracking. Besides the benefits of using one or other of these non-conventional interfaces, a combination of them could further improve human-system interaction, through exploring each approach's advantages for specific corresponding tasks. A solution adopted for implementation with the navigation in the virtual environments' application is explained. Results are discussed and perspectives are given for future developments.

Because of their thermal and biological resistance, diamondoids have been used to assess the thermal maturity of light oils and condensates. Combined with biomarker data, they have also been applied to the characterization of mixtures of oils with contrasting maturity levels from distinct migration pulses in a single petroleum accumulation. We analyzed 22 oils from a Colombian sedimentary basin using gas chromatography coupled with mass spectrometry (GC/MS) to identify and characterize their biomarker and diamondoid distributions. Ratios of diamondoids and biomarkers provide a more refined maturity assessment because most of the oils have been biodegraded. Our integrated interpretation of the biomarker and diamondoid data allowed us to recognize different levels of thermal maturity in the oils, as well as to consider possible mixtures of oils from distinct migration pulses.

This paper describes the use of Bayesian spatial models to develop the concept of a spatial-temporal mask for the purpose of identifying regions in which before and after drilling effects are most clearly defined and from which the consequences of exposure of macrofauna and meiofauna to the release of drilling discharges can be evaluated over time. To determine the effects of drilling fluids and drill-cuttings on the marine benthic community, it is essential to know not only where discharged materials ended up within the possible impact area, but also the chemical concentrations to which biota were exposed during and after drilling. Barium and light hydrocarbons were used as chemical tracers for water-based and non-aqueous-based fluids in a shallow water site in the Campos Basin, off the coast of Brazil. Since the site showed evidence of exposure to waste material from earlier drilling, the analysis needed to take into account the background concentrations of these compounds. Using the Bayesian models, concentrations at unsampled sites were predicted and regions altered and previously contaminated were identified.

This work reports results obtained with the use of a game engine as a tool to create and to navigate in virtual environments, to perform simulations and training of workers in risky areas, for safety purposes. The game engine used can be used for non-commercial and educational purposes, and its source code is available for users. Thus, the engine can be modified and adapted for the modeling and simulation of any environment, including the development of new functionalities. A case study is shown, which has the purpose of supporting dose assessment in nuclear plants, for optimization of operational routines in these areas. The implemented modifications are explained, and simulations' results are shown.

Toxic drilling fluids and cutting discharges from oil and gas wells adversely affect local environment near the well site. To determine their effects on benthic communities, it is essential to know both the fate of the discharged materials and the chemical concentrations to which biota were exposed during and after drilling. This paper describes a mapping procedure using Bayesian spatial models to define the deposition area of drilling cuttings and fluids from an exploratory well in a deep-sea site in the Campus Basin, RJ, Brazil, taking into account the concentrations of barium and light hydrocarbons used as chemical tracers. The statistical procedures used allow comparisons between sampled sites and the prediction of results at unsampled sites, as well as the delineation of affected areas. The probable impact of the use of non-aqueous fluid (NAF) was measured through observed changes in sea-floor sediments by using Before–After Control-Impact comparisons in a study with three moments: one before drilling and two after drilling.

Diamondoids are compounds commonly found in oils. Highly stable, they are more resistant to thermal and biological destruction than other hydrocarbons. Diamondoid-derived parameters have been used to assess the degree of thermal evolution and the extent of secondary cracking of light oils and condensates and in the identification of mixtures of oils from distinct migration pulses. Twenty-one samples of oils from five sedimentary basins of Brazilian continental margin were selected and studied on diamondoids and biomarkers. The oil samples were analyzed by gas chromatography coupled to mass spectrometry and principal components analysis (PCA) aiming to correlate biomarker and diamondoid parameters. Diamondoid and biomarker ratios analyzed by PCA led to a more accurate assessment of the maturity of the oils. The combination of diamondoid data with biomarker parameters also allowed to rank the oils from one of the five basins (JX basin) as the most mature oils, while oils from another basin (JE basin) were classified as mixtures formed from different pulses of migration.

Current nuclear power plant simulators employ interfaces that use multiple computer displays to represent a simplified control desk. To make the simulation more realistic and effective, a proposed approach replaces the displays with a virtual control desk that precisely mimics the original.

We study a one-dimensional multi-species system of dispersive-advective contaminant transport equations coupled by nonlinear biological (kinetic reactions) and physical (adsorption) processes. To deal with the nonlinearities and the coupling, and to avoid additional computational costs, we propose a linearization technique based on first-order Taylor’s series expansions. A stabilized finite element in space, combined with an Euler implicit finite difference discretization in time, is used to approximate the dispersive-advective transport problem. Three computational tests are performed with different boundary conditions, retardation factors and kinetic parameters for a nonlinear reactive multi-species transport model. The proposed methodology is shown to be accurate and decrease computational costs in the numerical implementation of nonlinear reactive transport problems.

After the concession of marine blocks for exploration and production of oil and natural gas in the last decade, oil industries activities became to exert greater pressure on the marine and coastal environments of Brazil. The BM-J-2 block is located about 20 km away from the coast of Una, Canavieiras and Belmonte municipalities in the Southern region of Bahia State. This region is constituted by important coastal marine ecosystems, some of them protected by law. This context makes this area mentioned sensitive to impacts from potential oil spill accidents. This work aims to map the environmental sensitivity to oil spills, using remote sensing and in situ data. Therefore, the production of maps representing littoral sensitivity index (LSI) in different hydrodynamics modeling scenarios is important for the implementation of contingency and emergency plans. Moreover, regional studies of geomorphology, land cover and land use were also used to construct the LSI charts. Those revealed different levels of environmental sensitivity to oil spill LSI ranging from 1 (lowest sensitive) to LSI 10, depending on the hydrodynamic conditions. This study shows the importance of considering the spatial and seasonal variability of hydrological, oceanographic and atmospheric processes in order to understand of environmental sensitivity of the coastal ecosystems.

This study evaluates how climate change might affect advective heat and volume transports in the South Atlantic Basin based on Intergovernmental Panel on Climate Change (IPCC) A1FI and B1 climate change scenarios projections. Using the Climatic Model 2.1 (CM2.1) results that were developed by the Geophysical Fluid Dynamics Laboratory (GFDL), integrated on the water column, analyses were conducted through two meridional sections and one zonal section of the study area (between 25◦S-70◦S and 70◦W-20◦E). The annual mean time series were analyzed using historical 100-year climate change scenarios. The analyses of the climate change experiment parameters were compared with those of the H2 climate scenario. The volume transport (VT) through the water column weakened of about 5% in average and the advective heat transport (HT) increased of about 22% at the Drake and Africa-Antarctic (AF-AA) passages at the end of the experiments. For the zonal section at 25◦S, direction oscillations were observed in the integrated VT through the water column due to velocity intensity variations of the water masses and a decrease of about 22% in the HT was observed. Thus, it was observed a decrease in the water and heat supplies at 25◦S due to the Drake and AF-AA VT behavior, which may alter deep circulation patterns.Keywords: water column analysis, advective heat transport, flow direction, Drake Passage, Africa-Antarctic passage.RESUMO. Baseado nas projeções dos cenários de mudanças climáticas A1FI e B1 do Painel Intergovernamental de Mudanc¸as Climáticas (IPCC), esse estudo avalia como as mudanças climáticas podem impactar os transportes advectivos de calor e volume na bacia do Atlântico Sul. Através de resultados gerados pelo Modelo Climático 2.1 (CM2.1) desenvolvido pelo Geophysical Fluid Dynamics Laboratory (GFDL), foram feitas análises através de duas seções meridionais e uma seção zonal na área de estudo (entre 25◦S-70◦S e 70◦W-20◦E) integradas na coluna d’água. Foram analisados campos prognósticos médios anuais referentes a experimentos com 100 anos de duração. As análises dos parâmetros dos experimentos de mudanças climáticas foram realizadas em comparação com o experimento clima (H2). O transporte de volume (TV) integrado na coluna d’água enfraqueceu aproximadamente 5%, enquanto o transporte advectivo de calor (TC) aumentou em torno de 22% no Drake e na Passagem África-Antártida (AF-AA) ao final dos experimentos. Para a seção em 25◦S, foram observadas oscilações de direção do fluxo devido a variações na intensidade das velocidades das massas d’água com um enfraquecimento médio de 22% para o TC. Adicionalmente, foi observada uma diminuição no suprimento de água em 25◦S devido ao comportamento do TV das demais seções, o que pode alterar os padrões de circulação profunda.Palavras-chave: análise na coluna d’água, transporte advectivo de calor, direção do fluxo, Passagem de Drake, passagem África-Antártida.

This chapter describes the ocean observation and data assimilation modules of Projeto Azul, a three-year operational oceanography pilot program for Santos Basin (southeastern Brazil from 23oS to 28oS) started in 2013. Systematic data collection in the Brazil Current meander and Cabo Frio eddy was performed by satellite-tracked surface drifters (surface currents, temperature, and atmospheric pressure), floats (vertical profiles of temperature and salinity), and gliders (vertical profiles of temperature, salinity, dissolved oxygen, turbidity, chlorophyll, and dissolved organic matter) creating an unforeseen data density in the region. The first tests of a 4D-VAR data assimilation scheme on a ROMS regional grid suggest an improvement of the ocean modeling short-range forecasts for the Santos Basin.

High porosity and low permeability limestone has presented pore collapse. As fluid is withdrawn from these reservoirs, the effective stresses acting on the rock increase. If the strength of the rock is overcome, pore collapse may occur, leading to irreversible compaction of porous media with permeability and porosity reduction. It impacts on fluid withdrawal. Most of reservoirs have been discovered in weak formations, which are susceptible to this phenomenon. This work presents a study on the mechanical behaviour of a porous limestone from a reservoir located in Campos Basin, offshore Brazil. An experimental program was undergone in order to define its elastic plastic behaviour. The tests reproduced the loading path conditions expected in a reservoir under production. Parameters of the cap model were fitted to these tests and numerical simulations were run. The numerical simulations presented a good agreement with the experimental tests. Copyright © 2006 John Wiley & Sons, Ltd.

A new a posteriori error estimate for finite element stress analysis is proposed. This engineering approach is characterized by using local reference systems that allows establishing which stress components must be continuous and which may not be continuous at interfaces between two elements. It is shown that, for a 3D analysis, only three stress components are sufficient to evaluate the stress error, and for a 2D analysis only two stress components are needed. Some 2D examples are considered and excellent results are obtained for both homogenous and heterogeneous materials.

It is well established that a wellbore may fail under tension or shear compressive modes. Recently, the behavior of porous rocks has been studied, showing that they may fail because of hydrostatic compression. Cap models may represent the compacting behavior of porous rocks. This work presents a comparison among Drucker–Prager, Mohr–Coulomb, and cap model in wellbore stability analysis for a borehole drilled in 30% porosity limestone from a deep water reservoir, Campos Basin, offshore Brazil. It shows that traditional models used in wellbore stability analysis may lead to erroneous conclusions about the stability in the vicinities of the borehole.

Stabilized finite element formulations and post-processing techniques are presented for Darcy flow and miscible displacement problems. In these techniques all primary unknowns are approximated in space by standard equal-order interpolations. We presented a review of the main mathematical results, including convergence estimates for global post-processing to solve the pressure–velocity problem and for the stabilized solution of the complete set of coupled partial differential equations in both space–time and semi-discrete frameworks. Demonstration problems are solved to show that we obtained numerically high rates of convergence than those predicted, achieving good accuracy in the solution of monophasic flow problems in adverse conditions.

Interface finite elements have been used in many geotechnical and engineering applications. Essentially, these elements must allow relative displacements between two bodies in contact, or separated by a thin material layer. Frequently, interface elements behave as linear elastic bodies up to a limiting stress state. This linear behavior of interfaces is very important, because it will establish when the slip and/or separation occurs, causing stress redistribution over the mesh. In this paper, the mechanical behavior of interface elements is discussed. It is shown that the kinematic inconsistency pointed by Kaliakin and Li [Comp. Geotech. 17 (1995) 225] for the element proposed by Goodman et al. [ASCE J. Soil Mech. Fdns. Div. 99 (1968) 637] also occurs for other interface models, and new interface elements for 2D and 3D analyses without kinematic inconsistencies are proposed.

This paper presents a study on the use of industrial internet of things (IIoT), the use of IIot in the current Brazilian industry context, its basic differences from internet of things (IoT) and its expansion possibilities pointing out some challenges related to a new approach within the industry. The complex interconnection which is made possible through the IIoT is able to optimise resources and reduce exponentially the costs of production processes in most stages and is gradually changing the direction of society in labour relations. These advances in manufacturing processes are feasible as the internet of things is not simply inserting intelligence in equipment, but allowing interconnection, reconfiguring functions and anticipating loss of productivity or failures that might occur in real-time. Within this context, the IIoT can be understood as a broad and complex concept that encompasses asset and performance management areas, availability of increased data and intelligent corporate.

The Santos Basin region is located in the southeast part of Brazilian offshore region and contains the most important presalt oil reservoirs. The oceanographic knowledge of this region is very important for the future challenges related with oil exploration and production. The Ocean Observing System for Santos Basin also known as Blue Project started in August 2012 and its main goal is the development of a pioneer ocean observing system for Santos Basin region (Brazil) based on ocean modeling applications and real time systematic ocean data collection [1]. The data collection program makes use of satellite remote sensing and in situ sensors such as surface drifters, floaters and gliders. The proposed methodology is based in three main research work branches: ocean and atmosphere modeling, real time ocean data collection and disclosure of all the generated information. In this work it will be presented the description of the applied methodology and the preliminary results achieved by the Project.Copyright © 2014 by ASME

This paper describes an edge-based implementation of the generalized residual minimum (GMRES) solver for the fully coupled solution of non-linear systems arising from finite element discretization of shallow water equations (SWEs). The gain in terms of memory, floating point operations and indirect addressing is quantified for semi-discrete and space–time analyses. Stabilized formulations, including Petrov–Galerkin models and discontinuity-capturing operators, are also discussed for both types of discretization. Results illustrating the quality of the stabilized solutions and the advantages of using the edge-based approach are presented at the end of the paper. Copyright © 2001 John Wiley & Sons, Ltd.

A finite element formulation is proposed to approximate a nonlinear system of partial differential equations, composed by an elliptic subsystem for the pressure–velocity and a transport equation (convection–diffusion) for the concentration, which models the incompressible miscible displacement of one fluid by another in a rigid porous media. The pressure is approximated by the classical Galerkin method and the velocity is calculated by a post-processing technique. Then, the concentration is obtained by a Galerkin/least-squares space–time (GLS/ST) finite element method. A numerical analysis is developed for the concentration approximation. Then, stability, convergence and numerical results are presented confirming the a priori error estimates.

A shell simultaneously supports membrane and plate bending actions, and both shear and membrane locking may occur. If the element is plane, bending and membrane effects are uncoupled, and the shell element is formed by the assembly of plate and membrane elements. This was proposed in the early sixties, but its success was hampered by the lack of good triangular plate elements. Shear locking has been the major problem, and it may be eliminated by using discrete Reissner–Mindlin models. In this paper, we used some discrete triangular plate elements to form flat shells. Membrane and shear locking are studied.

This paper deals with h -adaptive strategy for two-dimensional dynamic analysis of non-linear materials. The procedure updates the spatial mesh in order to keep or recover an established error level. The overlay model and the Duvaut–Lions flow rule are employed, respectively, in the description of the plastic and of the visco-plastic behaviours. The visco-plastic, elastic and plastic responses are obtained by the same computational code, only changing the imposed value of the viscosity coefficient. Numerical examples illustrate the capacity of the adaptive strategy to recover the actual response, even when the converged solution is completely different from the initial mesh approach.

This study aimed to describe the use of bendsensors to analyze the human body joints range of movement (ROM). To achieve this goal, we used a system integrating an electronic platform and bendsensors, which is able to capture frontal and sagittal planes movements. A program written in the Processing 1.2.1 language was developed to allow information conversion obtained by the electrical bendsensor resistance variation in degrees, which are shown in a computer screen. After installing the program, we defined the size and position of each bendsensor to capture the hand, knee and ankle ROM. The results indicated that the proposed sensor could be useful to analyze hand ROM, but it is limited by its format to analyze knee and ankle ROM in the frontal and sagittal planes. Other limitations of the system bendsensor/electronic platform are: the need of a wire connection from the bendsensor to the electronic platform and from the platform to a computer; the small number of the developed electronic platform analogical inputs; the impossibility to evaluate movements in the transverse plane (i. e. rotation); the difficulty to evaluate complex movements, which involve more than one plane. Another limitation is the necessity to validate these sensors to improve the confidence of the ROM evaluation by them.

In this paper we describe a methodology to simulate tracer flow, using finite element methods. After time domain discretization, classical Galerkin's method is used to approximate the pressure equation and then the velocity is accurately calculated through pressure gradients, Darcy's law and a post-processing technique. To solve the concentration equation, we use a streamline upwind Petrov-Galerkin (SUPG) method in two steps. An h-adaptive finite element technique is also adopted. Numerical results are presented illustrating the applications of these techniques to a five spot geometry.

Many finite elements based on Reissner-Mindlin plate bending theory with discrete constraints have been developed in the past few years. This approach avoids the C 1 continuity required by the classical Kirchhoff plate theory. However, in those elements the shape functions for deflections (or their derivatives) are not integrated. Particularly in DKT (discrete Kirchhoff triangle) and in DST (discrete shear triangle) elements, the lateral deflections are defined only on the boundaries. In the paper we briefly discuss the definition of the transverse displacement for these elements, and present a simple approach to define a pseudoconsistent load vector and mass matrix

Submitted by Jairo Amaro (jairo.amaro@sibi.ufrj.br) on 2019-07-01T16:41:27Z No. of bitstreams: 1 2012_PIMENTEL_IJEP_v48_p194-min.pdf: 1562131 bytes, checksum: 35aba882011922b521faa6b2d28e34ae (MD5) Made available in DSpace on 2019-07-01T16:41:27Z (GMT). No. of bitstreams: 1 2012_PIMENTEL_IJEP_v48_p194-min.pdf: 1562131 bytes, checksum: 35aba882011922b521faa6b2d28e34ae (MD5) Previous issue date: 2012-10-11 Indisponível. This work presents the results of a photochemical modelling system composed of MM5-SMOKE-CMAQ on Brazilian Amazonia area, been a pioneered implementation task. These results focus on the biogenic and biomass burning emissions and the impact of these emissions on regional air quality. Global and local anthropogenic emissions data, satellite-derived biomass burning inventories, and biogenic emissions calculated with MEGAN model were used to estimate emissions over the domain. The goal is the development of air quality model input data for CMAQ. Results are consistent with O3 formation theory and CO hotspot concentration matches with the geographic area of biomass burning.