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A Review of Telemetry Data Transmission in Unconventional Petroleum Environments Focused on Information Density and Reliability 被引量:4
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作者 Ivamberg Navarro de Almeida Jr. Pedro Duarte Antunes +3 位作者 Felipe Orlando Centeno Gonzalez Roberto Akira Yamachita Andreas Nascimento Jose Luiz Goncalves 《Journal of Software Engineering and Applications》 2015年第9期455-462,共8页
The paper addresses a literature review of the technologies used in the transmission of measuring and logging data during well drilling. It presents a discussion about efficiency in data density transmission and relia... The paper addresses a literature review of the technologies used in the transmission of measuring and logging data during well drilling. It presents a discussion about efficiency in data density transmission and reliability, especially when it comes to software and automated tools. Initially, this paper analyzes the principle of the telemetry systems, considering the mud pulse telemetry, acoustic telemetry, electromagnetic telemetry and wired drill pipe telemetry. They were detailed highlighting information about functionality, data transmission and its linkage to supporting software. Focus is also given to details of the main advantages and disadvantages of each technology considering the influences of lithology, drilling fluid and formation fluids in the reliability and capacity of data transmission. 展开更多
关键词 LWD MWD Mud-Pulse Wired-Drill-Pipe Drilling Fluid Telemetry TRANSMISSION
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The VILMA intelligent vehicle:an architectural design for cooperative control between driver and automated system 被引量:2
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作者 Olmer Garcia Giovani Bernardes Vitor +2 位作者 Janito Vaqueiro Ferreira Pablo Siqueira Meirelles Arthurde Miranda Neto 《Journal of Modern Transportation》 2018年第3期220-229,共10页
Intelligent autonomous vehicles have received a great degree of attention in recent years. Although the technology required for these vehicles is relatively advanced, the challenge is firstly to ensure that drivers ca... Intelligent autonomous vehicles have received a great degree of attention in recent years. Although the technology required for these vehicles is relatively advanced, the challenge is firstly to ensure that drivers can understand the capabilities and limitations of such systems and secondly to design a system that can handle the interaction between the driver and the automated intelligent system. In this study, we describe an approach using different strategies for an autonomous system and a driver to drive a vehicle cooperatively. The proposed strategies are referred to as cooperative planning and control and determine when and how the path projected by the autonomous system can be changed safely by the driver to a path that he wishes to follow. The first phase of the project is described, covering the design and implementation of an autonomous test vehicle. Experiments are carried out with a driver to test the cooperative planning and control concepts proposed here. 展开更多
关键词 Autonomous vehicles Embedded systems Cooperative systems Visual servoing
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Detection of Partial Discharge in Power Transformers Using Rogowski Coil and Multiresolution Analysis 被引量:1
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作者 G.F.C. Veloso L.E. Borges da Silva +4 位作者 I. Noronha G. Lambert Torres J. Haddad R.R. Pereira Se UnAhn 《Journal of Energy and Power Engineering》 2010年第2期39-45,共7页
Partial discharge detection in power transformers is discussed using a new approach that exploit the broad band of the Rogowski coils and the potential of two signal processing tools: discrete wavelet transform and e... Partial discharge detection in power transformers is discussed using a new approach that exploit the broad band of the Rogowski coils and the potential of two signal processing tools: discrete wavelet transform and empirical mode decomposition. Detecting and analyzing incipient activities of partial discharge can provide useful information to diagnostics and prognostics about transformer insulation. So, partial discharge signals embedded in the electric current at ground conductor are measured using the Rogowski coil. These signals are submitted to noise suppression and the partial discharges waveforms are extracted through different ways: using discrete wavelet transform and using empirical mode decomposition. The comparison of these two methods show that the extraction with discrete wavelet transform results in a faster and simpler algorithm than the empirical mode decomposition. But this one produces more precise waveforms due its adaptive characteristic. 展开更多
关键词 Discrete wavelet transform empirical mode decomposition partial discharge power transformer Rogowski coil.
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Single-Phase Velocity Determination Based in Video and Sub-Images Processing:An Optical Flow Method Implemented with Support of a Programmed MatLab Structured Script 被引量:1
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作者 Andreas Nascimento Edson Da Costa Bortoni +2 位作者 José Luiz Goncalves Pedro Antunes Duarte Mauro Hugo Mathias 《Journal of Software Engineering and Applications》 2015年第6期290-294,共5页
Important in many different sectors of the industry, the determination of stream velocity has become more and more important due to measurements precision necessity, in order to determine the right production rates, d... Important in many different sectors of the industry, the determination of stream velocity has become more and more important due to measurements precision necessity, in order to determine the right production rates, determine the volumetric production of undesired fluid, establish automated controls based on these measurements avoiding over-flooding or over-production, guaranteeing accurate predictive maintenance, etc. Difficulties being faced have been the determination of the velocity of specific fluids embedded in some others, for example, determining the gas bubbles stream velocity flowing throughout liquid fluid phase. Although different and already applicable methods have been researched and already implemented within the industry, a non-intrusive automated way of providing those stream velocities has its importance, and may have a huge impact in projects budget. Knowing the importance of its determination, this developed script uses a methodology of breaking-down real-time videos media into frame images, analyzing by pixel correlations possible superposition matches for further gas bubbles stream velocity estimation. In raw sense, the script bases itself in functions and procedures already available in MatLab, which can be used for image processing and treatments, allowing the methodology to be implemented. Its accuracy after the running test was of around 97% (ninety-seven percent);the raw source code with comments had almost 3000 (three thousand) characters;and the hardware placed for running the code was an Intel Core Duo 2.13 [Ghz] and 2 [Gb] RAM memory capable workstation. Even showing good results, it could be stated that just the end point correlations were actually getting to the final solution. So that, making use of self-learning functions or neural network, one could surely enhance the capability of the application to be run in real-time without getting exhaust by iterative loops. 展开更多
关键词 Optical Flow Single-Phase Velocity Video and Image Processing Sensing MatLab Script
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Hot Blast Flow Measurement in Blast Furnace in Straight Pipe
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作者 Ricardo S. N. Motta Edson C. Bortoni Luiz E. Souza 《Modern Instrumentation》 2013年第4期68-73,共6页
This article shows an innovative method to model and validate the hot air flow through the blast furnacés tuyeres. This study will be the basis for flow measurements implementation and safety interlocks for the p... This article shows an innovative method to model and validate the hot air flow through the blast furnacés tuyeres. This study will be the basis for flow measurements implementation and safety interlocks for the pulverized coal injection. The flow measurements were taken in the blast furnace down leg pipes by installing refractory Venturi tubes. The system for the calculation of differential pressure takes into consideration the dimension of the Venturi, the air density and compressibility. The objective is to specify the flow transmitters required to automate a control system and implement safety interlocks for the coal injection plant. 展开更多
关键词 BLAST Furnacés Tuyeres STRAIGHT PIPE HOT Air Flow COAL Injection
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Linear Generator Used in Hybrid System Solar Biomass
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作者 Angelo Jose Junqueira Rezek Carlos Rocha +6 位作者 Wladimir Cobas Electo E. S. Lora Paulo S. P. Correa Jr.t Osvaldo J. Venturini Rubenildo Andrade Jose C. Escobar Marcelo Pirani 《Journal of Mechanics Engineering and Automation》 2015年第6期382-385,共4页
The aim of this paper is to present the linear generator (Stirling solar dish) in the context of a HSSB (hybrid system solar biomass), project P & D (research and development P & D 0041, in cooperation and part... The aim of this paper is to present the linear generator (Stirling solar dish) in the context of a HSSB (hybrid system solar biomass), project P & D (research and development P & D 0041, in cooperation and partnership with CPFL--LIght and Force Paulista Company-Campinas, Piratininga, S.P. Brazil). The other components of the system will be the solar ORC (organic Rankine cycle), the rotary Stifling and the biomass gasifier. The integration of the complete system will be described in the paper, and is projected to be hydraulic one. 展开更多
关键词 Linear generator Stirling solar dish electric-hydraulic integration.
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Software Tool Development and Application Focusing in EDF Signal Readings and Polysomnography
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作者 Iúri Barros Werneck Dotta Santiago Santos Manganoti Andreas Nascimento 《Journal of Software Engineering and Applications》 2015年第9期463-469,共7页
The EDF+ (European Data Format Plus) is a flexible and open source data format created in order to store and exchange biomedical signals. It is known worldwide and used by a large variety of specialists in the area. E... The EDF+ (European Data Format Plus) is a flexible and open source data format created in order to store and exchange biomedical signals. It is known worldwide and used by a large variety of specialists in the area. EDF+ signals have been subjected to many researches of clinical interest amongst diagnosing and for treatment of diseases related to sleeping disorders. Nevertheless, more complete and user-friendly tools, which use these signals, are yet too few in the market. This paper presents a new tool developed in order to read and analyze EDF+ signals, focusing in the area of sleep disorders. It includes several features, such as organizing signal channels through previous montage customizations, sleep stage bars and graphics for analyzing the quality of sleep (hypnograms). It provides easiness in the whole process of interpretation and scoring of sleep events in polysomnography exams. The software development used the C++ language, due to its great versatility and efficiency, using Visual Studio Community 2013? as the Integrated Development Environment (IDE). Moreover, it implements many Digital Signal Processing (DSP) techniques, for instance, its own set of digital filters. This paper presents an application of Polysomnography analysis software and suggests a modification on the way to interpret the EDF+ standard and its usage. 展开更多
关键词 POLYSOMNOGRAPHY EDF SIGNAL Analysis Medicine Automation SLEEP DISORDERS C++
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Numerical Study of Natural Convection in Square Cavity with Inner Bodies Using Finite Element Method
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作者 Renato José Pinto Paulo Mohallem Guimarães Genésio José Menon 《Open Journal of Fluid Dynamics》 2016年第2期75-87,共13页
A numerical study of heat transfer problem by natural convection of a fluid inside a square cavity with two inner bodies is presented. This subject is of great interest in the engineering area, mainly in applications ... A numerical study of heat transfer problem by natural convection of a fluid inside a square cavity with two inner bodies is presented. This subject is of great interest in the engineering area, mainly in applications involving development of heat exchangers and cooling or heating systems of bodies by natural convection mechanism. Two cases have been studied. The inner bodies are square in case 1 and circular in case 2. In both cases, the bodies are solid and thermally conductive, the cavity lower and upper horizontal surfaces are isothermal with high temperature Th and low temperature Tc, respectively. Both vertical surfaces are adiabatic. A FORTRAN code using Finite Element Method (FEM) is developed to simulate the problem and solve the governing equations. The distributions of stream function, ψ, dimensionless temperature, θ, and vorticity, ω, are determined. Heat transfer is evaluated by analyzing the behavior of the average Nusselt number. The Grashof number and thermal diffusivity ratio are considered in range from 2 × 104 to 105 and from 0.1 to 100, respectively. The fluid is air with Prandtl number fixed in 0.733. 展开更多
关键词 Heat Transfer Natural Convection Square Cavity Finite Element Method Inner Body
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Artificial Neural Networks in Risk Management: A Bibliometric Study
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作者 Breno Gontijo Tavares Carlos Eduardo Sanches da Silva Adler Diniz de Souza 《Journal of Business Administration Research》 2021年第1期29-36,共8页
This study presents a bibliometric analysis of Artificial Neural Networks in Risk Management.The study considered articles from the I.S.I.Web of Knowledge and Scopus databases,Identification of publishers,countries,pe... This study presents a bibliometric analysis of Artificial Neural Networks in Risk Management.The study considered articles from the I.S.I.Web of Knowledge and Scopus databases,Identification of publishers,countries,periodicals and the keywords most frequently cited.We used the CiteSpace® software to analyze this material,which provides a set of features to support bibliometrics,including the reference maps.This study provides data collection on Artificial Neural Networks applied to risk management.The number of works identified in this study is significant,and in the last ten years,the number of citations has increased.We did not identify the increase in paper count within the same period. 展开更多
关键词 Bibliometric study Artificial neural networks Risk management I.S.I.Web of knowledge SCOPUS
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Elemental Composition of PM<sub>2.5</sub>in Araraquara City (Southeast Brazil) during Seasons with and without Sugar Cane Burning
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作者 Flavio Soares Silva Ricardo Henrique Moreton Godoi +4 位作者 Romà T auler Paulo Afonso de André Paulo Hilário Nascimento Saldiva Rene van Grieken Mary Rosa Rodrigues de Marchi 《Journal of Environmental Protection》 2015年第5期426-434,共9页
Particulate matter with an aerodynamic diameter below 2.5 μm (PM2.5), present in polluted air, has been associated with a large spectrum of health impairments, mainly because of its deep deposition into the lungs. Ar... Particulate matter with an aerodynamic diameter below 2.5 μm (PM2.5), present in polluted air, has been associated with a large spectrum of health impairments, mainly because of its deep deposition into the lungs. Araraquara City (Southeast Brazil) is surrounded by sugar-cane plantations, which are burned to facilitate the harvesting;this process causes environmental pollution due to the large amounts of soot that are released into the atmosphere. In this work, the elemental composition of PM2.5 was studied in two scenarios, namely in sugar-cane harvesting (HV) and in non-harvesting (NHV) seasons. The sampling strategy included one campaign in each season. PM2.5 was collected using a dichotomous sampler (10 L·min-1, 24 h) with PTFE filters. Information concerning the bulk elemental concentration was provided by energy-dispersive X-ray fluorescence. Enrichment factor analysis indicated that S, Cl, K, Cr, Ni, Cu, Zn, As, Cd and Pb were highly enriched relative to their crustal ratios (to Al). Principal component analysis was used to get some insight about the sources of the elements. Principal component 1 (PC1) explained 30.5% of data variance. The elements that had high loading (>0.7) were: S, Cr, As, and Pb;these are associated with combustion of fossil fuels. In principal component 2 (PC2), Cl, Cu, Zn, and Cd showed high loadings;these elements are associated with biomass burning. The Ni concentration found is three times larger than the threshold of risk for lung cancer, as recommended by the World Health Organization. 展开更多
关键词 SUGAR-CANE BURNING PM2.5 Individual Particle ANALYSIS EDXRF Cluster ANALYSIS Principal Components ANALYSIS
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Red-emitting CaWO4:Eu^(3+),Tm^(3+)phosphor for solid-state lighting:Luminescent properties and morphology evolution
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作者 L.X.Lovisa I.M.P.da Silva +5 位作者 A.A.G.Santiago M.Siu Li E.Longo C.A.Paskocimas M.R.D.Bomio F.V.Motta 《Journal of Rare Earths》 SCIE EI CAS CSCD 2022年第2期226-233,I0002,共9页
CaWO_(4):xEu^(3+),yTm^(3+)crystals were obtained by facile synthesis at low temperature by the microwaveassisted hydrothermal method(MAH).The phase formation,morphology,luminescent properties and ene rgy transfer were... CaWO_(4):xEu^(3+),yTm^(3+)crystals were obtained by facile synthesis at low temperature by the microwaveassisted hydrothermal method(MAH).The phase formation,morphology,luminescent properties and ene rgy transfer were investigated.The X-ray diffraction(XRD)re sults show the formation of a scheelitelike tetragonal structure without the presence of secondary phases.The growth mechanism of hierarchical micro structures based on self-assembly and Ostwald-ripening processes was evaluated,obtaining different types of morphologies.The luminescence spectra of CaWO_(4):Eu^(3+),Tm^(3+)at 325 nm excitation show the predominance of red emission at the 5 D0→7 F2(Eu^(3+))transition at 624 nm.This feature signals dominant behavior of the electric dipole type.The presence of Tm^(3+)is notably evident in the absorption spectra by the related excitation transitions:3 H6→1 G4,3 H6→3 F3 and 3 H6→3 H4.Color parameters are discussed to characterize CaWO_(4):Eu^(3+),Tm^(3+)emission.The study of the emission spectrum as a function of the concentration of Eu^(3+)(x mol%)and Tm^(3+)(y mol%)indicates that the CaWO_(4):Eu^(3+),Tm^(3+)phosphors show stronger red emission intensity and exhibit the CIE value of x=0.63 and y=0.35.The photoluminescence results show 97%high color purity for CaWO_(4):4 mol%Eu^(3+),a high CRI(92%)and a low CCT of 1085 K.These results demonstrate that the CaWO_(4):Eu^(3+),Tm^(3+)red phosphors are promising as color converters for application in white light-emitting diodes and display devices. 展开更多
关键词 CaWO_(4):Eu^(3+) Tm^(3+)microwave-assisted hydrothermal method Photoluminescence Red phosphor Rare earths
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