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1st International Symposium on Instrumentation Systems, Circuits and Transducers, INSCIT 2016

作者： Da Silva, Paulo Fernandes Freire, Raimundo Carlos Silverio Serres, Alexandre Jean Rene Da Fonseca Silva, Paulo Henrique Costa E Silva, Jefferson Post-Graduate Program in Electrical Engineering -COPELE Federal University of Campina Grande UFCG Campina Grande Brazil Post-Graduate in Electrical Engineering PPGEE Federal Institute of Paraiba João Pessoa Brazil

ISBN: (纸本)9781509033027

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. © 2016 IEEE.

关键词： Bandwidth

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Indoor temperature variation with different roof materials and natural ventilation 33

Indoor temperature variation with different roof materials a...

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33rd International on Passive and Low Energy Architecture Conference: Design to Thrive, PLEA 2017

作者： Drach, Patricia R. Architecture and Urbanism Department School of Industrial Design State University of the Rio de Janeiro - DAU/ESDI/UERJ Rio de Janeiro Brazil Post-Graduate Program in Urbanism School of Architecture and Urbanism Federal University of Rio de Janeiro PROURB/FAU/UFERJ Rio de Janeiro Brazil Urban Engineering Program Federal University of Rio de Janeiro PEU/POLI/UFRJ Rio de Janeiro Brazil

ISBN: (纸本)9780992895754

This work involves experiments using subroutines developed by the author in Fortran language to calculate heat and mass transfer, and ventilation. The simulations were done to check the results of the influence of the application of different materials on a flat roof associated to passive ventilation. The target of this paper is to evaluate the use of subroutines developed to show air temperature changes, the heat transfer through a flat roof and the ventilation on a small prototype. The experiments conducted involved predictable results and that is exactly why they were suitable to check the performance of the subroutine. It is relevant to mention that the heat transfer through a flat roof was checked including a solar gain factor, which changes during the simulation using the subroutines, according to the hour of day (hourly from 7a.m. to 5p.m). The analysis started by solving the air-circulation problem to determine the wind fields, using a mixed stabilized finite element method, like Petrov-Galerkin, applied to the full Navier-Stokes equations. The thermal problem is analyzed through the SUPG - Streamline Up-wind Petrov-Galerkin stabilized finite element method. Computational simulations allow for testing low cost operational interferences before implementing a project. © Copyright 2017 NCEUB.

关键词： Ventilation

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Kinetic studies of potassium permanganate adsorption by activated carbon and its ability as ethylene oxidation material

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IOP Conference Series: Earth and Environmental Science 2018年第1期141卷

作者： F Aprilliani E Warsiki A Iskandar Post Graduate Program of Agroindustrial Technology Bogor Agricultural University Bogor Indonesia Department of Agroindustrial Technology Faculty of Agricultural Engineering and Technology Bogor Agricultural University Bogor Indonesia

Generally, ethylene production in many horticultural products has been seen to be detrimental to the quality during storage and distribution process. For this reason, removing ethylene from storage or distribution atmosphere is needed to maintain the quality. One of the technologies that can be applied is the use of potassium permanganate (KMnO4). KMnO4 is an active compound that can be used as an oxidizing agent on ethylene removal process. KMnO4 is not recommended for direct used application. As the result, additional material is required to impregnate the potassium permanganate. The inert materials used are commercial activated carbon. Activated carbon is chosen because it has high surface area. The purpose of this research is to determine kinetics adsorption and oxidation model of ethylene removal material. The kinetics adsorption was determined using the pseudo-first and second-order kinetic models. The data on adsorption process show that the second-order equation is more suitable to express the adsorption process on this research. The analyzing of the ethylene oxidation capacity increased with time until it reaches an optimal value. The ethylene oxidation rate is able to be estimated by the formula r = 0.1967 [C2H4]0.99 [KMnO4]0.01; MSE = 0.44 %. The actual and estimation data of ethylene oxidation show that the model is fitted to describe the actual ethylene oxidation under same experimental conditions.

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System identification of a pilot scale heat exchanger: A state-space realization approach 42

System identification of a pilot scale heat exchanger: A sta...

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42nd Conference of the Industrial Electronics Society, IECON 2016

作者： Lima, Rafael B. C. Barros, Péricles R. Acioli, George Post-graduate Program in Electrical Engineering PPgEE COPELE UFCG Brazil Electrical Engineering Department Fed. University of Campina Grande Brazil

It is presented a state-space realization approach for identification of a pilot scale heat exchanger plant. The proposed methodology is a computational efficient way to estimate state-space models from experimental d...

ISBN: (纸本)9781509034741

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Single-Phase AC-DC-AC Current Source Converter With Reduced DC-Link Oscillation

Single-Phase AC-DC-AC Current Source Converter With Reduced ...

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Applied Power Electronics Conference and Exposition

作者： Louelson A. Costa Montiê A. Vitorino Maurício B. R. Corrêa Post-Graduate Program in Electrical Engineering - PPgEE - COPELE Federal University of Campina Grande (UECG) Campina Grande - PB - Brazil Department of Electrical Engineering Federal University of Campina Grande (UECG) Campina Grande - PB - Brazil

ISBN: (纸本)9781509053674

In this work it is presented an AC-DC-AC synchronization technique that aims to reduce the DC-link current oscillation. The technique is applied to a reduced component count single-phase back-to-back Currente Source Converters (CSC). The deduction of how the DC-link oscillation is influenced by both input and output angles is presented. Experimental and simulation results are provided to validate the theoretical approach and to illustrate the synchronization phenomenon.

关键词： CSC illustrate synchronization phenomenon

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Fatigue strength of welded joints under multiaxial non-proportional loading

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Procedia Structural Integrity 2017年 5卷 761-768页

作者： Sabrina Vantadori Joel Boaretto Giovanni Fortese Felipe Giordani Roberto Isoppo Rodrigues Ignacio Iturrioz Camilla Ronchei Daniela Scorza Andrea Zanichelli Department of Engineering & Architecture University of Parma Parco Area delle Scienze 181/A 43124 Parma Italy Mechanical Post- Graduate Program Federal University of Rio Grande do Sul Sarmento Leite 425 CEP 90050-170 Porto Alegre Brazil

Fatigue behaviour of a fillet-welded tubular T-joint in the so-called H structural component of an agricultural sprayer is examined by using experimental strain measurements found in the literature and linear elastic finite element analyses. Two stress-based critical plane criteria are applied at a verification point located near the intersection between the end of brace and chord of the above-mentioned T-joint, where crack initiation and growth is experimentally observed.

关键词： agricultural sprayer critical plane-based criteria multiaxial fatigue non proportional loading T-joint

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Analysis of Lead (Pb) and Zinc (Zn) Content in Sediments and Faunus ater at Bale Lhoknga Aceh Besar District

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Journal of Physics: Conference Series 2019年第1期1232卷

作者： Rahmi Agustina M. Ali Sarong Fredinan Yulianda Suhendrayatna Rahmadi Lelifajri Graduate School of Mathematics and Applied Sciences Syiah Kuala University Banda Aceh Indonesia 23111 Departement of Biology Faculty of Teacher Training and Education Jabal Ghafur University Sigli Indonesia 24171 Departement of Biology Faculty of Teacher Training and Education Syiah Kuala University Banda Aceh Indonesia 23111 Departement of Water Resources Management Faculty of Fisheries and Marine Sciences Bogor Agricultural University Bogor Indonesia 16680 Department of Chemical Engineering Faculty of Engineering Syiah Kuala University Banda Aceh Indonesia 23111 Department of Chemistry Faculty of Mathematics and Science Post Graduate Program Syiah Kuala University Banda Aceh Indonesia 23111

Faunus ater is a favoritemollusca that is often found on the Bale River. Local people use these snails as food for consumption along with their main food. Bale River itself is located adjacent to the cement factory, used water washing machines distributed to the river is feared to support the presence of lead (Pb) and zinc (Zn) metals in the river. This study aims to analyze the relationship of Pb and Zn content in sediments to the content of Pb and Zn in Faunus ater. Data collection was carried out in Februari until April 2018. The relationship between Pb and Zn content in sediments with Pb and Zn content in the body of Faunus ater was analyzed by correlation analysis. The results of the data analysis showed that the metal content of Pb and Zn in sediment and Faunus aterwere found to vary. The highest Pb content in sediment was found at station 2 in March, amounting to 32.87 mg / kg. while the highest Zn content was found at station 1 in March amounting to 84 mg / kg. The relationship of heavy metals Pb and Zn in sediments to the content of Pb and Zn in the body of Faunus ater showed a negative correlation. The conclusion of this study is that there is no correlation between the content of Pb and Zn heavy metals in sediments on the content of lead Pb and Zn in the body of Faunus ater at the Bale Lhoknga River in Aceh Besar District.

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Asymmetrical cascaded three-phase AC-DC converters with injection transformers

Asymmetrical cascaded three-phase AC-DC converters with inje...

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IEEE Energy Conversion Congress and Exposition

作者： Joao Paulo R. A. Mello Cursino B. Jacobina Post-Graduate Program in Electrical Engineering (PPgEE/COPELE) Federal University of Campina Grande (UFCG) Campina Grande Paraíba Brazil Department of Electrical Engineering (DEE) Federal University of Campina Grande (UFCG) Campina Grande Paraíba Brazil

ISBN: (纸本)9781509029990

In this paper, three configurations of three-phase ac-dc cascaded converters are presented. They are referred as basic configurations, and are composed by two three-phase bridges, where the second bridge is cascaded to the first by means of a three-phase injection transformer. Basic configurations have one bidirectional option (composed only by IGBT switches), and two unidirectional ones (composed by IGBT and diodes). Their generalizations, which are composed by an indefinite number of cascaded three-phase bridges, are also proposed. Each additional cascaded bridge is a three-phase IGBT bridge and requires one additional three-phase injection transformer. Transformers turns ratios are calculated in order to maximize the number of levels produced in the ac side of each rectifier, enhancing power quality. Basic configurations are compared by means of simulations between themselves and with the conventional three-phase IGBT bridge, to show that proposed multilevel rectifiers present better performance in terms of ac power quality drew from the ac source, with lower semiconductor losses. Experimental results are also exposed for the basic configurations to validate them and show their feasibility.

关键词： Bridge circuits Insulated gate bipolar transistors Topology Semiconductor diodes Legged locomotion Integrated circuit modeling Mathematical model

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Selection of sensitive features for damage identification in a railway bridge

Selection of sensitive features for damage identification in...

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作者： Meixedo, A. Alves, V. Ribeiro, D. Calçada, R. Faculty of Engineering University of Porto Portugal Post-Graduate Program in Civil Engineering Federal University of Ouro Preto Brazil School of Engineering Polytechnic of Porto Portugal

This paper aims selects sensitive features for damage identification in a railway bridge. For this purpose, a damage identification methodology based on a genetic algorithm and its application to the numerical model of a railway bridge is proposed. The identification method is based on an iterative process that in each iteration compares the values of the dynamic responses of a bridge for a test damage scenario with the response values for a reference damage scenario. The introduction of damage in the test numerical model is based on the modification of preselected numerical parameters values. The genetic algorithm allows the identification of damage by minimizing the residue of an objective function constructed from the responses of the test and reference model, and based on damage indicators. In this study damage indicators, based on the deck accelerations of the bridge subject to the action of the Alfa Pendular train defined as a set of moving loads, are defined and tested. The proposed methodology for identifying damage has been tested using a two-dimensional numerical finite element model of a railway bridge including the railway track. The results enabled the evaluation of the efficiency and reliability of the methodology and of the damage indicators which, in most situations, showed potential for the detection, location and quantification of the severity of the damage. © Civil-Comp Press, 2016.

关键词： Genetic algorithms

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Proposal of a Hotspot-based Approach to Identifying Social Impacts along the Product-Service Systems Life Cycle in the Early Design Phases

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Procedia CIRP 2017年 64卷 85-90页

作者： Thayla T. Sousa-Zomer Paulo A. Cauchick-Miguel Post-graduate Program in Production Engineering Federal University of Santa Catarina Campus Universitário Trindade Caixa Postal 476 88040-970 Florianópolis SC Brazil Production and System Engineering Department Federal University of Santa Catarina Campus Universitário Trindade Caixa Postal 476 88040-970 Florianópolis SC Brazil

The potential for sustainability has been highlighted as one of the most important characteristics of product-service systems (PSS). Nevertheless, a PSS is not intrinsically sustainable. Methods and tools for PSS sustainability assessment should be developed to be integrated into the design process, especially in the early design phases, in order to conceive sustainable solutions. In addition, a PSS should be planned considering the three sustainability dimensions, from a life cycle perspective. However, PSS design and assessment considering the full life cycle is scarcely addressed in the literature, especially concerning the social dimension of sustainability. In this sense, this study proposes a streamlined life cycle assessment based approach to identify potential social impacts along the PSS life cycle that can be integrated into the early PSS design stages. The proposal is based on a hotspot analysis, which identifies where in the life cycle the most significant issues may occur. The proposal was developed in three main phases, anchored in both hotspots analysis and PSS literature. After developing it, 10 experts in PSS and sustainability assessed the proposal strengths and weakness. Some suggestions were offered by the researchers and improvements were introduced to the proposal regarding PSS life cycle phases and the social impact subcategories. The experts considered the hotspot analysis suitable to be applied in the early design stages when there is not much information yet regarding the system to conduct a complete life cycle assessment. The next step of this research is the proposal assessment by practitioners in industry. Further work will also integrate the environmental dimension of sustainability into the proposal.

关键词： sustainable product-service systems sustainability assessment social impacts early design stages

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