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Determination of time zero in high strength concrete containing superabsorbent polymer and nano-silica

Journal of Building Pathology and Rehabilitation 2016年第1期1卷 1-12页

作者： Cunha, T.A. Francinete, P. Manzano, M.A. Aidar, L.A. Borges, J.G. Silva, E.F. Post-Graduate Program in Structures and Civil Construction (PECC/UnB) University of Brasília Brasília Federal District Brazil Civil Engineering Department (ENC/UnB) University of Brasília Brasília Federal District Brazil

The autogenous shrinkage is a phenomenon that occurs due to the appearance of tensile stresses in capillary pores. Inherent in the hydration process, not depending on external interference. In high strength concrete, autogenous shrinkage is most pronounced, due to the refinement of microstructure, the high cement content, presence of mineral addictions and low water/cement ratio, which interfere in the transport of water curing. In this context, Superabsorbent polymers (SAP) stand out for their ability to reduce or eliminate the autogenous shrinkage, because they absorb large amounts of water, which is subsequently released into the matrix, avoiding self-desiccation and the onset of tensile stresses (internal curing). However, studies show that SAP can reduce the mechanical strength, which can be compensated by addiction of Nano-silica (NS). In this paper, the effect of these additions in Time Zero (T₀) was evaluated. T₀ determines the time at which the material starts to behave as a solid, with the development of a rigid mineral skeleton to oppose the volumetric variations that occurs in the paste, which can lead to cracking, compromising esthetics, durability, and structures safety. The ultrasonic pulse velocity test performed the T₀, which measures the velocity of propagation of an ultrasonic wave through the material and is taken as the time when a sudden change occurs at this velocity. Nine blends were made containing SAP and NS, where it was found that SAP addition increases the T₀ (up to 11%), while NS decrease its value (in 55%). © 2016, Springer International Publishing Switzerland.

关键词： High performance concrete High strength concrete Nano-silica Superabsorbent polymer Time zero Ultrasonic pulse velocity

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Modeling and control of a XY positioning table 12

Modeling and control of a XY positioning table

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12th IEEE International Conference on Industry Applications, INDUSCON 2016

作者： Moreira, Lucas J. Da S. Dias, Christian C. Lima, Rafael B. C. Barros, Pericles R. Acioli, George Post-Graduate Program in Electrical Engineering-PPgEE COPELE Federal University of Campina Grande-UFCG Campina Grande PB58429-900 Brazil Graduate Program in Electrical Engineering-PGEE Federal University of Campina Grande-UFCG Campina Grande PB58429-900 Brazil Electrical Engineering Department-DEE Federal University of Campina Grande-UFCG Campina Grande PB58429-900 Brazil

ISBN: (纸本)9781509051274

This paper is about modeling and control of a XY positioning table. It is described the construction and instrumentation of a double axis positioning system. It is developed a general electromechanical model, followed by the identification of simplified models for control purposes. At last, it is proposed a PID control strategy, tuned by Internal Model Control (IMC) technique. © 2016 IEEE.

关键词： Three term control systems

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Status of heavy metal in sediment of Saguling Lake, West Java

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IOP Conference Series: Earth and Environmental Science 2017年第1期60卷

作者： E Wardhani D Roosmini S Notodarmojo Environmental Engineering Program ITB Post-Graduate Academy Bandung Indonesia Department of Environmental Engineering ITB Bandung Indonesia

The quality of water in the Saguling lake has been monitored since 1990 by the state agency for environmental control. However, no data on heavy metal in sediment had been reported. Metal pollutans have receives considerable attention due to their persistence, biogeochemical recycling, and environmental risk. The objective of this study was to assess the level contamination of heavy metals (Cd, Cr, Cu, and Pb) in the surface sediment of the Saguling Lake West Java. Surface sediment samples were collected from 10 location of the Saguling Lake on July and November 2015. The concentration of heavy metals in the surface sediment on July and November 2015 decreased in the order of Cu>Cr>Pb>Cd and Cr>Cu>Pb>Cd respectively. Mean metals concentrations (mg/kg) in July 2015 were in the range of: Cd: 10.69-16.65, Cr: 76.67-138.38, Cu:106.02-229.54, Pb: 23.93-80.17. Mean metals concentrations (mg/kg) in November 2015 were in the range of Cd: 18.64-23.25, Cr: 152.16-197.98, Cu: 63.32-152.53, Pb: 20.31-32.74. Geochemical approaches such as contamination factor, and pollution load index were exploited for the assessment of the contamination and enrichment level of heavy metals in the lake sediment. Contamination factor and pollution load index values indicated that surface sediments around Saguling Lake were polluted with heavy metals. The finding of this study would help in formulating guidelines to control the pollution and suggested for Saguling lake revitalization.

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Proposal for a Brazilian regulation of electromagnetic compatibility applied to automotive vehicles

Proposal for a Brazilian regulation of electromagnetic compa...

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IEEE International Symposium on Electromagnetic Compatibility (EMC)

作者： Artur N. de São José Úrsula C. Resende Magno A. de Menezes José H. Ferreira Electrical Engineering Post Graduate Program Federal Center for Technological Education of Minas Gerais Belo Horizonte Brazil Electrical Engineering Post Graduate Program Pontifical Catholic University Belo Horizonte Minas Gerais Brazil

For the last two decades, electro-electronic components have become more and more integrated into automotive vehicles, with an increasing importance in essential functions implying the safe overall operation of the car. Although these innovations come as a car performance improvement, it can also have adverse effects (some related to safety) in case of malfunction. These undesirable behaviors can be caused by Electromagnetic Interferences (EMI), and the probability increases when a large number of electro-electronic components act together in the same environment, causing failures that may damage part or the whole system. In Brazil, the Electromagnetic Compatibility (EMC) validation of these systems is currently a relative option and the decision of testing or not (and how deep) is up to each car manufacturer. Moreover, most of these validations are still realized out of Brazil, turning developments more expensive, more time-consuming and underusing Brazilian metrology chain. This paper proposes a study of the Brazilian automotive EMC validation context and a comparison with the worldwide scenario, taking into account its technical, economic and social impacts and bringing arguments to discuss a possible federal regulation. This electronic document is a “live” template and already defines the components of your paper [title, text, heads, etc.] in its style sheet.

关键词： Electromagnetic compatibility Automotive engineering Standards Automobiles Industries Government

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Biological responses of fibroblasts and osteoblasts on modified bioactive titanium implant surfaces

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Clinical Oral Implants Research 2018年第S17期29卷

作者： Beatriz Ferreira Mariana Cruz Gabriella Peñarrieta-Juanito Joana Marques Filipe Silva João Caramês Júlio Souza Ricardo Magini Mafalda Costa Georgina Miranda António Mata Faculty of Dental Medicine Universidade de Lisboa Portugal Center for Research on Dental Implants Post-graduate program in dentistry (PPGO) School of Dentistry Federal University of Santa Catarina (UFSC) Brazil Oral Biology and Biochemistry Research Group LIBPhys Faculty of Dental Medicine University of Lisbon Portugal Center for Microelectromechanical Systems (CMEMS) Dept. of Mechanical Engineering University of Minho Portugal Bone Physiology Research Group LIBPhys Faculty of Dental Medicine University of Lisbon Portugal Center for Research on Dental Implants Post-graduate program in dentistry (PPGO) School of Dentistry Federal University of Santa Catarina (UFSC) Portugal

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Human osteoblast and fibroblast behavior on modified zirconia implant surfaces

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Clinical Oral Implants Research 2018年第S17期29卷

作者： Mariana Cruz Joana Marques Gabriella Peñarrieta-Juanito Filipe Silva António Mata Mafalda Costa Georgina Miranda Júlio Souza Ricardo Magini Silvio Mario Meloni João Caramês Faculty of Dental Medicine Universidade de Lisboa Portugal Oral Biology and Biochemistry Research Group LIBPhys Faculty of Dental Medicine University of Lisbon Portugal Center for Research on Dental Implants Post-graduate program in dentistry (PPGO) School of Dentistry Federal University of Santa Catarina (UFSC) Brazil Center for Microelectromechanical Systems (CMEMS) Dept. of Mechanical Engineering University of Minho Portugal Center for Research on Dental Implants Post-graduate program in dentistry (PPGO) School of Dentistry Federal University of Santa Catarina (UFSC) Portugal NA Italy Faculty of Dental Medicine University of Lisbon Portugal

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Numerical evaluation of the pressure drop in multiphase flow of the catenary riser with the presence of leakage

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Defect and Diffusion Forum 2016年 366卷 157-165页

作者： De Almeida Tavares, Daniela Passos Simões Sarmento, Lígia Rafaely Barbosa Barbosa, Enivaldo Santos De Farias Neto, Severino Rodrigues De Lima, Antonio Gilson Barbosa Federal University of Campina Grande Center of Science and Technology Post Graduate Program in Chemical Engineering Campina GrandeParaíba58429-900 Brazil Federal University of Campina Grande Center of Science and Technology Petroleum Engineering Department Campina GrandeParaíba58429-900 Brazil Federal University of Campina Grande Center of Science and Technology Mechanical Engineering Department Campina GrandeParaíba58429-900 Brazil

The growing demand for oil brings the need for discovery of deeper reservoirs, especially of ultra-deepwater reservoirs. Thus, production in marine systems using components such as risers (flexible or rigid pipes) has been the focus of many studies in different areas. These ducts are used in the transportation of multiphase fluids (oil, water and gas) produced from the oil well located on the seabed to the platform surface. Due to the extreme conditions present in the offshore fields of production, the equipments that transport produced fluids operate close to their limits. So eventually, the flexible pipes may have structural integrity faults like leaks, which can cause production losses, accidents with victims and environmental disasters. The leak depends of a number of properties or parameters measured at the site of the leak, for example, integrity of the pipe material, release of fluids and noise emission characteristics or manifestation of some other type of signal behavior, variation of pressure drops close to the leak, among others. There are a variety of techniques available for detecting leaks, among which there is the mathematical modeling approach using computational techniques. In this context, this paper aims to study the fluid dynamics of a transient multiphase flow in a catenary riser in the presence of leakage. Herein a 3D Eulerian-Eulerian model was applied, including the turbulent model (RNG k-ϵ), using the commercial package ANSYS CFX® 15 to perform all simulations. The numerical results of velocity, volume fraction and pressure of the involved phases are presented and discussed. © 2016 Trans Tech Publications.

关键词： Drops

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A quadratic approximation-based local search operator for handling two equality constraints in continuous optimization problems

A quadratic approximation-based local search operator for ha...

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Congress on Evolutionary Computation

作者： Carlos H. Fonseca Elizabeth Fialho Wanner Post-graduate Program in Mathematical and Computational Modeling MG Brasil Department of Computer Engineering MG Brasil

This work presents extensions of the general methodology of employing quadratic approximations of the objective function and constraints for handling non-linear equality constraints in single-objective optimization problems. The methodology does not require any extra function evaluation since the quadratic approximations are constructed using only information that would be already obtained in the course of the optimization algorithms. The methodology is coupled with the Real Biased Genetic Algorithm to tackle non-linear single-objective optimization problems with two equality constraints. The modified algorithm is tested with a set of analytical problems. The results show the modified algorithm finds the constrained optima with enhanced precision and faster convergence. Considering that the new technique does not impose any additional cost to the algorithms, it can be stated that the technique is also suitable for costly black-box problems.

关键词： Optimization Approximation algorithms Linear programming Search problems Genetic algorithms Symmetric matrices Convergence

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Relationship Population Density of Aquatic Sediment Macrozoobenthos to River Water Quality Parameters： Case Study of Upstream Citarum River in Bandung Regency

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Journal of Environmental Science and engineering(A) 2016年第3期5卷 117-125页

作者： Barti Setiani Muntalif Nurul Chasanah Mohammad Faiz Faza Departement of Environmental Engineering Institute Technology Bandung Bandung 40132 Indonesia Environmental Engineering Program Post-Graduate Academy Institute Technology Bandung Bandung 40132 Indonesia

The increase in anthropogenic activities occur along the upstream of Citarum River Basin （CRB） in Bandung regency had a negative impact to the water quality caused by the presence of human activity, it will be able to be a disruption to the ecosystem aquatic. The purpose of this study was to determine the relationship of the physical and chemical parameters of water and sediment to the presence of macrozoobenthos populations. Based on the result of Pearson Correlation Analysis （PCA）, the parameters of COD, TOC and silt composition were the highest correlation to the macrozoobenthos population density, the value were 0.966, 0.865 and 0.576. Although PCA analysis is used to determine the relationship between the parameters of water, sediment and sediment particle distribution, the result showed that the water parameters were the mayor component affected the density of macrozoobenthos. While based on the composition of sediment, it is found that substrate as silt, clay and gravel and phosphate parameter affected the density of macrozoobenthos. The measurement of water quality also were calculated by Biotic Monitoring Working Party-Average Score Per Taxon （BMWP-ASPT） index showed that the quality were polluted condition, although by Pollution Index （IP） method showed as a light polluted category.

关键词： Citarum upstream correlation sediment macrozoobenthos water quality.

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Bio-inspired antenna for UWB systems

Bio-inspired antenna for UWB systems

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International Symposium on Instrumentation Systems, Circuits and Transducers (INSCIT)

作者： Paulo Fernandes da Silva Raimundo Carlos Silvério Freire Alexandre Jean René Serres Paulo Henrique Da Fonseca Silva Jefferson Costa e Silva Post-Graduate Program in Electrical Engineering - COPELE Federal University of Campina Grande UFCG Brazil Post-Graduate Program in Electrical Engineering - COPELE Federal University of Campina Grande UFCG Campina Grande Brazil Universidade Federal de Campina Grande Campina Grande PB BR Post-Graduate in Electrical Engineering PPGEE Federal Institute of Paraiba IFPB Brazil Post-Graduate in Electrical Engineering PPGEE Federal Institute of Paraiba IFPB Joao Pessoa Brazil

In this paper is presented a new printed monopole antenna, bio-inspired by jasmine flower, that meets the Federal Communications Commission parameters for ultra-wideband systems. The design of the printed monopole antenna in jasmine flower has developed from a printed monopole antenna with circular geometry, with comparison results. The measured results of bio-inspired antenna in the jasmine flower showed compatibility with the parameters required by the FCC for ultra-wideband technology. It obtained bandwidth of 9.75 GHz, half-power beamwidth of 148 degrees, omnidirectional radiation pattern, gain of 5.99 dBi, power spectral density below -41.3 dBm across the bandwidth of ultra-wideband technology, small pulse distortion, and constant group delay, with variations of less than 2ns.

关键词： FCC Ultra wideband antennas Antenna measurements Bandwidth Geometry Distortion Frequency measurement

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