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A pressao do dia a dia influencia muito na vida das pessoas. O estudo tem o objetivo de mostrar como essa rotina afeta o trabalho dos coletores de lixo, ja que tem seu trabalho todo programado com data e hora, alem de nao terem a... more
A pressao do dia a dia influencia muito na vida das pessoas. O estudo tem o objetivo de mostrar como essa rotina afeta o trabalho dos coletores de lixo, ja que tem seu trabalho todo programado com data e hora, alem de nao terem a condicoes necessarias para realizarem seu trabalho fazendo com que os coletores fiquem expostos a inumeros fatores de risco. Para a realizacao da pesquisa, foi elaborada uma entrevista semiestruturada, onde o coletor de lixo relatou sua percepcao corporal durante a coleta de lixo e em momentos de lazer.
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A consciencia corporal e nocao que as pessoas tem de seu corpo de forma biologica, psicologica e social. Sabemos que muitas vezes as pessoas perdem essa consciencia devido a rotina do dia a dia, com inumeros compromissos como trabalho,... more
A consciencia corporal e nocao que as pessoas tem de seu corpo de forma biologica, psicologica e social. Sabemos que muitas vezes as pessoas perdem essa consciencia devido a rotina do dia a dia, com inumeros compromissos como trabalho, familia, estudos entre outros que devem ser realizados em um curto tempo, sem contar no tempo de lazer que precisa ser encaixado nessa rotina. O trabalho repetitivo e automatico pode ser um dos fatores que contribuem para a perda de consciencia do corpo. Um exemplo deste modelo de trabalho e o realizado pelos lixeiros. A coleta do lixo tem data e hora marcada para ser realizada, e necessita ser feita com rapidez e eficiencia, desta forma, os lixeiros a realizam de qualquer maneira, sem necessariamente, pensar na melhor forma “motora” de desenvolve-la, o que pode gerar o desencadeamento ou o aumento de lesoes, a longo ou curto prazo, no periodo trabalhado. Um dos motivos para essas lesoes pode ser a falta de consciencia corporal durante a execucao dos ...
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Nowadays, the amount of data produced by machines and human activity is growing in size and complexity in an exponential rate. These huge datasets and the technology developed to deal with them were coined with the name big data. The... more
Nowadays, the amount of data produced by machines and human activity is growing in size and complexity in an exponential rate. These huge datasets and the technology developed to deal with them were coined with the name big data. The MapReduce concept, implemented by Hadoop and its related open source software components make possible to process and understand this huge amount of data with scalability and performance. Despite these great advances, this technology lacks of an user interface, and only professionals with programming skills are able to manipulate correctly all these components. This work proposes an open source user interface to run Hadoop jobs and manipulate results through RapidMiner interface, as well a tool API to facilitate the integration of Hadoop with other user interfaces. The experiments done with the comparison of clustering algorithms showed that an user interface for Hadoop is an attractive entry point for new big data practitioners, and a powerful environm...
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In offshore field development it is extremely important to plan the submarine pipeline route for the hydrocarbons transportation. To ensure an expedited project, researchers from Petrobras and LAMCSO/COPPE/UFRJ have been involved in the... more
In offshore field development it is extremely important to plan the submarine pipeline route for the hydrocarbons transportation. To ensure an expedited project, researchers from Petrobras and LAMCSO/COPPE/UFRJ have been involved in the development and implementation of a computational tool, based on Evolutionary Algorithms, for the synthesis and optimization of submarine pipeline routes. In this tool, each candidate route is evaluated in terms of several criteria that are incorporated in an objective function, to take into account the relevant aspects that should be considered in the design of a route, such as the pipeline length, bathymetry data, obstacles, number and length of free spans and others. Previous works described the incorporation of engineering criteria related to on-bottom stability and VIV-induced fatigue in free spans for pipes under the action of hydrostatic and hydrodynamic environmental loads of current and waves. Now, this work presents more examples of applica...
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In deep and ultra-deep water petroleum exploitation activities, floating production systems such as semi submersible platforms and FPSO (Floating Production, Storage and Offloading) units have been commonly employed. However, the... more
In deep and ultra-deep water petroleum exploitation activities, floating production systems such as semi submersible platforms and FPSO (Floating Production, Storage and Offloading) units have been commonly employed. However, the utilization of flexible risers in ultra-deep waters has been hindered by technical and economical reasons. On the other hand, first order motions from the floating unit due to environmental loads are not favorable to the use of Steel Catenary Risers (SCR) in a free-hanging configuration. This fact has motivated several studies on hybrid riser systems, including the system studied in this work, which is based on a sub-surface buoy with large dimensions, moored to the seabed by tethers. This system employs flexible lines connecting the floating unit to the buoy, in the region where dynamic effects are more relevant due to the floating unit motions, and also SCRs that extend from the buoy to the seabed, in the region where dynamic motions are not so significant. The objective of this work is to describe a solution procedure for the analysis of such a hybrid riser system. This procedure is based on an analytical formulation that is solved numerically. One of the main features of this procedure is the fact that it takes into account the effects of current loads acting on the lines. Current profiles can be considered, with direction and velocities varying with depth, therefore configuring a full three-dimensional solution. This procedure can be employed either as a preliminary static analysis tool, to be used in parametric studies in order to assess the feasibility of candidate configurations of hybrid riser systems, or else for the generation of finite-element meshes for a full time-domain nonlinear dynamic simulation. It is important to start the dynamic simulation from a statically balanced configuration, since the transient effects can be dramatically shortened and the total simulation time can be reduced. The results obtained from this procedure are compared with a discrete solution obtained using a nonlinear finite-element based solver. The strategy considered here is intended to be an approach that will speed up the tasks involved in the design of hybrid risers systems based on the subsurface buoy concept.
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Researchers from Petrobras and LAMCSO/COPPE have been involved in the development and implementation of a computational tool, based on Evolutionary Algorithms, for the synthesis and optimization of submarine pipeline routes. In this tool,... more
Researchers from Petrobras and LAMCSO/COPPE have been involved in the development and implementation of a computational tool, based on Evolutionary Algorithms, for the synthesis and optimization of submarine pipeline routes. In this tool, randomly generated candidate routes are evaluated in terms of several criteria, incorporated in an objective (or fitness) function to take into account the relevant aspects that should be considered in the design of a route. Previous works described the initial steps taken towards the development of such tool, including the geometrical representation of a route, and some of the terms of the objective function associated with a preliminary, global step of the optimization process (such as total pipeline length, and geographical-topographical issues associated with the route geometry and to the seabed bathymetry and obstacles). Special attention was dedicated to the implementation of On-Bottom Stability (OBS) criteria such as the proposed in the DNV-...
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ABSTRACT This work deals with optimization methods for the selection of submarine pipeline routes, employed to carry the oil & gas from offshore platforms. The main motives are related to the assessment of constraint-handling... more
ABSTRACT This work deals with optimization methods for the selection of submarine pipeline routes, employed to carry the oil & gas from offshore platforms. The main motives are related to the assessment of constraint-handling techniques, an important issue in the application of genetic algorithms and other nature-inspired algorithms to such complex, real-world engineering problems. Several methods associated to the modeling and solution of the optimization problem are addressed, including: the geometrical parameterization of candidate routes; their encoding in the context of the genetic algorithm; and, especially, the incorporation into the objective function of the several design criteria involved in the route evaluation. Initially, we propose grouping the design criteria as either "soft" or "hard", according to the practical consequences of their violation. Then, the latter criteria are associated to different constraint-handling techniques: the classical static penalty function method, and more advanced techniques such as the Adaptive Penalty Method, the epsilon-Constrained method, and the Ho-Shimizu technique. Case studies are presented to compare the performance of these methods, applied to actual offshore scenarios. The results indicate the importance of clearly characterizing feasible and infeasible solutions, according to the classification of design criteria as "soft" or "hard" respectively. They also indicate that the static penalty approach is not adequate, while the other techniques performed better, especially the epsilon-Constrained and the Ho-Shimizu methods. Finally, it is seen that the optimization tool may reduce the design time to assess an optimal route, providing accurate results, and minimizing the costs of installation and operation of submarine pipelines.
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Researchers from Petrobras and LAMCSO/COPPE/UFRJ are currently involved in the development and implementation of a computational tool, based in Evolutionary Algorithms, for the synthesis and optimization of submarine pipeline routes. In... more
Researchers from Petrobras and LAMCSO/COPPE/UFRJ are currently involved in the development and implementation of a computational tool, based in Evolutionary Algorithms, for the synthesis and optimization of submarine pipeline routes. In this tool, randomly generated candidate routes are evaluated in terms of several criteria, incorporated in an objective (or fitness) function to take into account the relevant aspects that should be considered in the design of a route. A previous work [1] described the initial steps taken towards the development of such tool. In that work, attention was dedicated to the geometrical representation of a route, and to some of the terms of the objective function associated with a preliminary, global step of the optimization process (such as total pipeline length, and geographical-topographical issues associated with the route geometry and to the seabottom bathymetry and obstacles). Now, this work focuses in other aspects related to the structural behavio...
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Abstract In offshore oil production activities, risers are employed to connect the wellheads at the sea-bottom to a floating platform at the sea surface. The design of risers is a very important issue for the petroleum industry; many... more
Abstract In offshore oil production activities, risers are employed to connect the wellheads at the sea-bottom to a floating platform at the sea surface. The design of risers is a very important issue for the petroleum industry; many aspects are involved in the design of such ...
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Research Interests: Engineering, Mathematics, Computer Science, Structural Engineering, Monte Carlo Simulation, and 15 moreFinite element method, Probabilistic Logic, Mathematical Sciences, Stochastic finite elements, Rio de Janeiro, Prediction Model, Seismic analysis and design, Uncertainty analysis, Discrete random variable, Fuzzy Set, Stochastic Finite Element Method, Monte Carlo Method, Probabilistic Approach, Perturbation method, and Structural system(Finite element method, Probabilistic Logic, Mathematical Sciences, Stochastic finite elements, Rio de Janeiro, Prediction Model, Seismic analysis and design, Uncertainty analysis, Discrete random variable, Fuzzy Set, Stochastic Finite Element Method, Monte Carlo Method, Probabilistic Approach, Perturbation method, and Structural system)
(Finite element method, Probabilistic Logic, Mathematical Sciences, Stochastic finite elements, Rio de Janeiro, Prediction Model, Seismic analysis and design, Uncertainty analysis, Discrete random variable, Fuzzy Set, Stochastic Finite Element Method, Monte Carlo Method, Probabilistic Approach, Perturbation method, and Structural system)
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This work presents two groups of FORTRAN routines, comprising portable programming tools for the development of structural analysis programs. These tools were applied in the enhancement of the CALEB program for collapse analysis of... more
This work presents two groups of FORTRAN routines, comprising portable programming tools for the development of structural analysis programs. These tools were applied in the enhancement of the CALEB program for collapse analysis of offshore platforms and general framed structures. The RINCOM (COMmand INterpreter Routines) group of routines was employed to build a pre-processor for CALEB, allowing data to be
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ABSTRACT This work presents a new surrogate model based on artificial neural networks (ANNs), comprising a rapid computational tool for the analysis and design of mooring lines and risers. The goal is to obtain results nearly as good as... more
ABSTRACT This work presents a new surrogate model based on artificial neural networks (ANNs), comprising a rapid computational tool for the analysis and design of mooring lines and risers. The goal is to obtain results nearly as good as those provided by expensive finite element (FE)-based nonlinear dynamic analyses, with dramatic reductions in processing time. The procedure proposed here associates an ANN with a Nonlinear AutoRegressive model with eXogenous inputs (NARX). Differently from previous models based purely on exogenous inputs (i.e. the platform motions), the NARX model relates the present value of the desired time series not only to the present and past values of the exogenous series, but also to the past values of the desired series itself. Case studies are presented to determine the best configurations for the model, and to evaluate its performance in terms of accuracy and computational time.
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The use of cooperative fusion systems for image interpretation has increased in the recent years and reliable ways to evaluate their performance are required. This paper focuses on a fusion system based on the Choquet Integral to detect... more
The use of cooperative fusion systems for image interpretation has increased in the recent years and reliable ways to evaluate their performance are required. This paper focuses on a fusion system based on the Choquet Integral to detect typical regions within 3D images. The complexity of the system can be a problem for the end-user that is not a specialist in computer sciences. Moreover, the global evaluation generally applied to quantify the system performance cannot describe well the system behaviour. In this paper, the main stages of the fusion system is firstly described in addition to several subparts, followed by the proposed local evaluation of each subpart. This proposed local evaluation is an interesting approach that can better characterize the system behaviour and consequently give information on which subpart need to be adjusted. The previously proposed local evaluation based on separability indexes, generates many numerical indicators when the number of inputs increase. So, a symbolic representation of these separability indexes is used such that it can be well understood by the experts. To overcome the application of a threshold, the uncertainty of the numeric measures is represented by possibility distributions. The developed methodology is applied on two different problems concerning 3D image analysis: a synthetic image containing three different regions and a 3D seismic image on the \textit{Marlim} oilfields.