901 resultados para submarine pipeline


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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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The air-assisted ground spray is fairly widespread. However, due to the unpredictable weather conditions, the operational efficiency is impaired by stops on grounds of low humidity and high temperatures. The aim of this work was to assess an air humidification method and evaluate its impact on temperature and air humidity for the air curtain of the air-assisted sprayer. With respect to relative air humidity, it has increased in 6.59%, being the maximum change when inserting 1.92 L min-1. So, it is concluded that the pipeline humidification might significantly reduce temperature and enhance air humidity. The treatments performed in this study consisted of a varied flow of a humidity device, related to weather conditions. Temperature and relative air humidity were measured at 1.0 m height from right to left of middle point of the machine, corresponding to the end of the spray boom, in the middle and end of right spray boom. The readings were also performed at three different distances from the end of the pipeline and at 0.25 and 0.50 m from that to the soil. The results show that 0.48 L min-1 in the humidification system has promoted a better efficiency in reducing air-temperature, on average 2.52 ºC when compared to the non-humidified one.

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In this paper we report on a search for short-duration gravitational wave bursts in the frequency range 64 Hz-1792 Hz associated with gamma-ray bursts (GRBs), using data from GEO 600 and one of the LIGO or Virgo detectors. We introduce the method of a linear search grid to analyze GRB events with large sky localization uncertainties, for example the localizations provided by the Fermi Gamma-ray Burst Monitor (GBM). Coherent searches for gravitational waves (GWs) can be computationally intensive when the GRB sky position is not well localized, due to the corrections required for the difference in arrival time between detectors. Using a linear search grid we are able to reduce the computational cost of the analysis by a factor of O(10) for GBM events. Furthermore, we demonstrate that our analysis pipeline can improve upon the sky localization of GRBs detected by the GBM, if a high-frequency GW signal is observed in coincidence. We use the method of the linear grid in a search for GWs associated with 129 GRBs observed satellite-based gamma-ray experiments between 2006 and 2011. The GRBs in our sample had not been previously analyzed for GW counterparts. A fraction of our GRB events are analyzed using data from GEO 600 while the detector was using squeezed-light states to improve its sensitivity; this is the first search for GWs using data from a squeezed-light interferometric observatory. We find no evidence for GW signals, either with any individual GRB in this sample or with the population as a whole. For each GRB we place lower bounds on the distance to the progenitor, under an assumption of a fixed GW emission energy of 10(-2)M circle dot c(2), with a median exclusion distance of 0.8 Mpc for emission at 500 Hz and 0.3 Mpc at 1 kHz. The reduced computational cost associated with a linear search grid will enable rapid searches for GWs associated with Fermi GBM events once the advanced LIGO and Virgo detectors begin operation.

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The electromechanical impedance (EMI) technique has been successfully used in structural health monitoring (SHM) systems on a wide variety of structures. The basic concept of this technique is to monitor the structural integrity by exciting and sensing a piezoelectric transducer, usually a lead zirconate titanate (PZT) wafer bonded to the structure to be monitored and excited in a suitable frequency range. Because of the piezoelectric effect, there is a relationship between the mechanical impedance of the host structure, which is directly related to its integrity, and the electrical impedance of the PZT transducer, obtained by a ratio between the excitation and the sensing signals.This work presents a study on damage (leaks) detection using EMI based method. Tests were carried out in a rig water system built in a Hydraulic Laboratory for different leaks conditions in a metallic pipeline. Also, it was evaluated the influence of the PZT position bonded to the pipeline. The results show that leaks can effectively be detected using common metrics for damage detection such as RMSD and CCDM. Further, it was observed that the position of the PZT bonded to the pipes is an important variable and has to be controlled.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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Pós-graduação em Engenharia Mecânica - FEG

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

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We present the first results of an all-sky search for continuous gravitational waves from unknown spinning neutron stars in binary systems using LIGO and Virgo data. Using a specially developed analysis program, the TwoSpect algorithm, the search was carried out on data from the sixth LIGO science run and the second and third Virgo science runs. The search covers a range of frequencies from 20 Hz to 520 Hz, a range of orbital periods from 2 to similar to 2,254 h and a frequency-and period-dependent range of frequency modulation depths from 0.277 to 100 mHz. This corresponds to a range of projected semimajor axes of the orbit from similar to 0.6 x 10(-3) ls to similar to 6,500 ls assuming the orbit of the binary is circular. While no plausible candidate gravitational wave events survive the pipeline, upper limits are set on the analyzed data. The most sensitive 95% confidence upper limit obtained on gravitational wave strain is 2.3 x 10(-24) at 217 Hz, assuming the source waves are circularly polarized. Although this search has been optimized for circular binary orbits, the upper limits obtained remain valid for orbital eccentricities as large as 0.9. In addition, upper limits are placed on continuous gravitational wave emission from the low-mass x-ray binary Scorpius X-1 between 20 Hz and 57.25 Hz.

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The pipelines are characterized by the great length and linearity, these enterprises are usually associated with the horizon of soil and decomposed rock and accidents in this system usually have high complexity. So this work proposes a study of geological and geotechnical characterization of approximately 40 km ² and a study of risk analysis along 18.3 km of gas pipeline GASBOL, in the municipalities of Ipeúna-SP and Itirapina-SP, in scale 1:25.000, besides correlation between studies. The method for geological and geotechnical characterization is based on physiographic integrated analysis technique, which is supported by literature research, observation and interpretation of satellite imagery (photointerpretation), correlation of products numerical model of ground, fieldwork. The method adopted for risk classification is based on preliminary analysis of hazards (APP) technique, which is identified the geological process, this feature is classified as the susceptibility of occurrence, and then classified as the possible consequence of the process, if this evolves. As a product of the research, we designed a map in 1:25,000 scale, containing a table of geological and geotechnical characteristics of the mapped drives, as well as sectorization risk in each section of the pipeline. Were mapped geological and geotechnical seven units in the study area, delimited in excerpts of which five are classified as high risk, totaling 1.1 km in length of 18.3 km total

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We conducted a study of the quality of water distributed by Artesian Well in relation to water supply served by the public for purposes of human consumption of UNESP Campus Guaratinguetá. Two sections of the network were randomly chosen and monitored for 105 days: the stretch of the pipeline started off the Water Treatment Station of the Autonomous Service of Water, Sewage and waste in the Municipality of Guaratinguetá and ended in a point consumption of the Child Family Center, while the section B began at the output of an artesian well and finished in a point of consumption of the Department of Civil Engineering. It is the deterioration of water quality in parts A and B, through comparative analysis of Bicarbonates, Total Hardness, Total Iron, free residual chlorine, pH, Total Residual, Turbidity, Conductivity, Color, Fecal Coliforms and Total Coliforms. Among the observations that can be highlighted: the Total Hardness was found in highest concentration in the extract; for Total Iron significant variations were obtained for both parts, and reduction of this parameter in two points of consumption analyzed, not the expected increase concentration, because the contact of water along the pipe, the CRL showed significant depletion to section A, which can be related to impurities in the water, the presence of biofilm on the walls of pipes, or because this is the stretch of greater extent to be covered by water for pH, this indicated that the water is alkaline and slightly acidic stretch in section B; Turbidity was found for the higher concentration to the passage, and a considerable reduction of this parameter at point consumption due to deposition of particulate matter along the stretch, the conductivity also showed a higher concentration in the extract, as well as an increase in this parameter at the point of consumption. Upon leaving ... (Complete abstract click electronic access below)

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Studies about structural integrity are very important when it desires to prevent disasters associated with flaws inherent in materials used in structural components. The welded joints in steel pipes used to conduction and distribution of oil and gas correspond to the regions most susceptible to flaw. Aiming to contribute to this research line, the present study was designed to assess experimentally the structural integrity of welded joints in steel pipes API 5L X70 used in pipeline systems. This assessment is given from tests of CTOD, whose aim is simulate in laboratory the real behaviour of crack from of his propagation on the welded joint obtained by high frequency electric resistance welding. In this case, the analyses are performed from specimens SE(B) obtained directly of steel pipe API 5L X70. The proposed methodology involves tests of CTOD at lower temperature, in order to assess the toughness of material in critical operation conditions. From performance of CTOD tests, was possible assess the toughness of welded joints in terms of quantity through CTOD parameter and in terms of quality from behaviour of curve load versus CMOD. In this study, also, sought to compare CTOD’s results obtained through rules ASTM E1820 (2008) and BS 7448 (1991). Although the two standards cited previously have adopted different parameters to calculated the value of CTOD, concluded that the values of CTOD tend to converge for a common value

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Taking into account the consistent and important expansion of the Brazilian oil and gas pipelines network in the last years, this work discusses how these lines are planned regarding the continental environmental context. Its central objective is to show how studies to select alternative lines are made before a gas or oil pipeline is installed. These studies help to choose routes in which the environment is less affected by the pipeline, and use specific methods, technologies, and tools. Bibliographical studies combined with interviews and discussions with experts of the oil and gas sector were used to support this monograph.

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The transportation of oil through pipelines raises a concern related to safety and environmental impacts they may cause, especially when exposed to risks that affect their integrity. Among the natural phenomena that can affect the pipelines are erosion and landslides. Considering the large territory involving the pipelines, remote sensing tools have a great applicability for data acquisition. For this, visual analysis techniques were applied to perform change detection in order to monitor erosion features and landslides along a stretch of pipeline Rio de Janeiro – Belo Horizonte, in the state of Rio de Janeiro. The work involved the characterization of the study area as well as the erosion and landslide processes, through bibliographical data. The satellite image processing and the application of change detection techniques were developed in two scenes for the years 2002 and 2010. It was noted a small increase in the number of the identified features, however with regard to their area, a decrease of 21.7% was observed

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The representation of real objects in virtual environments has applications in many areas, such as cartography, mixed reality and reverse engineering. The generation of these objects can be performed through two ways: manually, with CAD (Computer Aided Design) tools, or automatically, by means of surface reconstruction techniques. The simpler the 3D model, the easier it is to process and store it. However, this methods can generate very detailed virtual elements, that can result in some problems when processing the resulting mesh, because it has a lot of edges and polygons that have to be checked at visualization. Considering this context, it can be applied simplification algorithms to eliminate polygons from resulting mesh, without change its topology, generating a lighter mesh with less irrelevant details. The project aimed the study, implementation and comparative tests of simplification algorithms applied to meshes generated through a reconstruction pipeline based on point clouds. This work proposes the realization of the simplification step, like a complement to the pipeline developed by (ONO et al., 2012), that developed reconstruction through cloud points obtained by Microsoft Kinect, and then using Poisson algorithm