Publicações - engenharias
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VARANIS, MARCUS;
SILVA, ANDERSON LANGONE;
BALTHAZAR, JOSÉ MANOEL;
OLIVEIRA, CLIVALDO;
TUSSET, ANGELO;
José João de Espíndola
Palavra-chave:
Sommerfeld effect;
Nonlinear jump;
Dynamic Control in a Frequency Range;
Dynamic Characterization;
Synchrosqueezed Transforms
Áreas do conhecimento:
Engenharias; Mecânica dos Sólidos; Dinâmica dos Corpos Rígidos, Elásticos e Plásticos
resumo ...
Several applications in engineering, a mechanical system operates in the nonstationary regime, creating the possibility to generate nonlinearities in them. Time frequency analysis methods are using the processing of signals of a nonstationary nature, as well as for the characterization of nonlinearities in mechanical systems. A particular phenomenon seen in nonstationary systems is the Sommerfeld effect, which occurs due to the nonlinear interaction between a non-ideal energy source and a mechanical system. In this research we explore the use of synchronized wavelet transform for the characterization of the Sommerfeld effect and nonlinear jump phenomenon in mechanical systems in the frequency domain. Nonstationary signals were measured on a 3-DOF shear build structure. We applied the wavelet synchrosqueezed transform for Resonant Capture, Sommerfeld Effect and Nonlinear Jump Characterization. It is shown how the results of the synchrotron wavelet transform is more efficient than those of classical methods. Furthermore, the mother wavelet has little influence on the SWT-based results. The synchrosqueezed transform has the potential to characterization nonlinear parameters in nonstationary signals, in particular, resonant capture, Sommerfeld effect, and nonlinear jump. Further research should focus on overcoming issues in the SWT technique to improve parameter estimation of mechanical systems.
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Felippe do Valle;
Eva Veres;
Matthias Brodbeck;
Zhou Xiaoru;
Paulo Henrique Trombetta Zannin
Áreas do conhecimento:
Engenharias; Engenharia Elétrica; Telecomunicações;
Engenharias; Engenharia Mecânica; ACÚSTICA DE EDIFICAÇÕES
resumo ...
(pt)
Residents of large urban centers are daily exposed to urban noise pollution, especially to noise generated by traffic of vehicles. Environmental noise may harm the environment and the population's quality of life. Therefore, studies that aim to reduce the effects of noise pollution are extremely relevant. In urban divisions, there must be spaces between or in buildings to ensure access for people and vehicles. However, regarding sound transmission, these spaces are considered "weak points" as they ease the passage of urban noise to other spaces that have housing. Thus, this study, carried out in the city of Stuttgart/Germany, evaluates the influence of urban spaces called tunnel and canyon on the transmission of traffic noise to residential facades posterior to these spaces. Two locations were selected: the first with the presence of a tunnel-like space and the second with a canyon-like space. Through measurements and acoustic simulations, the current sound environment of the places was measured. In acoustic simulations, variations of geometric aspects and sound absorption coefficients of the internal surfaces of open spaces were also considered. The results show that the dimensions of open spaces are significant in sound transmission, especially the parameters width and height. The data also show that the installation of coatings with sound absorption on the internal surfaces of spaces is a viable measure from a technical point of view, as it resulted in an attenuation of up to 22 dB(A) on posterior facades.
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KOZAK, CAROLINE;
LEITHOLD, JULIANA;
DO PRADO, LUCIANE LEMOS;
Heloise Garcia Knapik;
DE RODRIGUES AZEVEDO, JÚLIO CÉSAR;
Sérgio Michelotto Braga;
Cristovão Vicente Scapulatempo Fernandes
Palavra-chave:
Diffuse Pollution;
Water Quality;
organic matter
Áreas do conhecimento:
Engenharias; Engenharia Sanitária; Recursos Hídricos; Planejamento Integrado dos Recursos Hídricos
resumo ...
Rainfall events induce water quality transformation in river systems influenced by the watershed land use and hydrology dynamics. In this context, an adaptive monitoring approach (AMA) is used to assess non-point sources (NPS) of pollution events, through dissolved organic matter (DOM) contribution. The case study is a monitoring site in a semi-urban watershed characterized by NPS contribution. An integrated quali-quantitative method for DOM based on dissolved organic carbon (DOC) content, spectroscopic techniques of excitation-emission fluorescence (EEF), and UV–visible absorbance is proposed. The results indicate a mix of allochthonous and autochthonous DOM characteristics from NPS sources associated to vegetation area influence (A285/DOC of 15.43 L (g cm)−1 and SUVA254 of 2.11 L (mg m)−1). The EEF signals showed more humic-like than protein-like characteristics with peaks A and C (approximately 5.72 r.u.) more intense than peaks B, T1, and T2 (approximately 4.33 r.u.), indicating NPS from the soil leachate. The absorbance ratio values indicate a mix of organic compounds with greater proportion of refractory characteristics with high aromaticity and molecular weight (approximately A300/A400 of 4.15 and A250/A365 of 4.48), associated with the surface wash-off of accumulated residual and subsurface soil erosion, which contribute to complex organic matter structures. The fluorescence indexes, overall, indicated allochthonous sources with intermediate humic characteristics (FI ≈ 1.43, BIX ≈ 0.65, and HIX ≈ 7.98). The proposed integrated optical property strategy represents an opportunity for better understanding of DOM dynamic assessment for identifying potential mitigation techniques for organic pollution control and improving water quality conditions.
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M. C. de Moraes;
I. S. Buth;
Caroline Angulski da Luz;
Eloise A. Langaro;
Marcelo Henrique Farias de Medeiros
Palavra-chave:
alkali-activated cement;
Alkali-aggregate reaction;
blastfurnace slag from charcoal;
reações expansivas
Áreas do conhecimento:
Engenharias; Engenharia Elétrica; Telecomunicações
resumo ...
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YAMAO, EDUARDO MASSASHI;
MAIDL, GABRIEL;
BORBA, JOÃO;
TOLEDO, CINTIA DE CARVALHO;
SANTOS, VICTOR LOPES;
PIEREZAN, JULIANO;
LEANDRO DOS SANTOS COELHO;
PENTEADO, RENATO
Palavra-chave:
turbinas à gás;
Metaheurísticas
Áreas do conhecimento:
Engenharias; Sistemas Elétricos de Potência; Geração da Energia Elétrica
resumo ...
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SÔnia Maria Assunção Veroneze;
Thais Helena Sydenstricker Flores-Sahagun;
RAMON SIGIFREDO CORTÉS PAREDES;
Kestur Gundappa Satyanarayana
Palavra-chave:
metal coatings;
polymer composite;
thermal spraying;
viscous filaments;
fractography
Áreas do conhecimento:
Engenharias; Engenharia de Materiais e Metalúrgica
resumo ...
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Lucas Emilio Hoeltgebaum;
DIAS, N. L.
Palavra-chave:
gap-filling;
latent heat flux;
eddy-covariance method
Áreas do conhecimento:
Ciências Exatas e da Terra; Meteorologia; Micrometeorologia;
Engenharias; Engenharia Civil; Engenharia Hidráulica; Hidrologia
resumo ...
Practically all records of eddy‐covariance flux measurements are affected by gaps, caused by several reasons. In this work, we propose analog period (AP) methods for gap‐filling, and test them for fi...
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LAROCA, RAYSON;
ZANLORENSI, LUIZ A.;
GONÇALVES, GABRIEL R.;
Eduardo Todt;
SCHWARTZ, WILLIAM ROBSON;
MENOTTI, DAVID
Palavra-chave:
algoritmos bioinspirados;
Classifiers;
Computer Vision;
controle de acesso;
convolutional neural networks;
deep learning
Áreas do conhecimento:
Ciências Exatas e da Terra; Ciência da Computação; Metodologia e Técnicas da Computação; Engenharia de Software;
Engenharias; Engenharia Elétrica; Telecomunicações
resumo ...
This paper presents an efficient and layout‐independent Automatic License Plate Recognition (ALPR) system based on the state‐of‐the‐art you only look once (YOLO) object detector that contains a unifi...
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TORRES, ANA PAULA ALVES;
DA SILVA, CLAUDIO BASTOS;
Horacio Tertuliano dos Santos Filho
Palavra-chave:
Vehicular Communication;
LORA;
V2L;
V2I;
genetic algorithm
Áreas do conhecimento:
Engenharias; Engenharia Elétrica; Telecomunicações;
Engenharias; Engenharia Elétrica; Telecomunicações;
Engenharias; Engenharia Elétrica; Telecomunicações; Sistemas de Telecomunicações
resumo ...
Among the profound changes that will come with the Internet of Things is vehicular communication. Shortly the vehicles will be connected between themselves (V2V) and their infrastructure. For the full achievement of these objectives, the challenges of new technologies are enormous due to the requirement of high reliability, high speed, and low latency. None of the technologies under development for this application has reached a satisfactory stage be assumed to as definitive. The LoRa technology, operating at frequencies below 1 GHz, presents a good signal spread and penetration in obstacles. It has a considerable range, open-source, simple, robust, and low-cost hardware, vast configuration possibilities, and applications, ranging from medicine to agriculture, do not use licensed bands. The tests proved to have good reach even in a dense urban environment. They can become a viable alternative in applications that require short message transmissions with few characters that do not require the constant sending of information packages. The purpose of this work is to evaluate the communication between V2I, V2V, and stationary vehicles using LoRa technology in field tests with measurements of signal strength, reception ratio, and signal-to-noise ratio. It will be using different SF (scattering factors) inherent to LoRa (SF7 and SF12) and evaluate the influence of the Doppler effect on communication.
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Eduarda Schwarzer;
Josy Anne dos Santos da Rocha;
Robson Seleme
Palavra-chave:
Logística reversa;
sustentabilidade;
Madeira Plástica
Áreas do conhecimento:
Engenharias; Engenharia Elétrica; Telecomunicações;
Engenharias; Engenharia de Produção; Sustentabilidade
resumo ...
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