Propagation Prediction Models
Mostrando 1-12 de 18 artigos, teses e dissertações.
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1. Preliminary investigation of Terahertz spectroscopy to predict pork freshness non-destructively
Abstract Freshness, a very important criterion for pork quality control, is normally assessed by the index of K value. In this paper, Terahertz (THz) spectroscopy was employed to predict K value of pork nondestructively. The THz spectra (0.2~2.0THz) of 80 pork samples with different freshness in the attenuated total reflectance (ATR) mode were acquired. Simu
Food Sci. Technol. Publicado em: 22/07/2019
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2. Comparing blast-induced ground vibration models using ANN and empirical geomechanical relationships
Abstract Blasting remains as an economical and reliable excavation technique, but there are some environmental shortcomings such as the control of blast-induced vibration. The impacts of vibration over surrounding communities in a blast area have been investigated for decades and researchers have been using a myriad of empirical predictive attenuation equati
REM, Int. Eng. J.. Publicado em: 2018-03
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3. A Hybrid Path Loss Prediction Model based on Artificial Neural Networks using Empirical Models for LTE And LTE-A at 800 MHz and 2600 MHz
Abstract This article presents the analysis of a hybrid, error correction-based, neural network model to predict the path loss for suburban areas at 800 MHz and 2600 MHz, obtained by combining empirical propagation models, ECC-33, Ericsson 9999, Okumura Hata, and 3GPP's TR 36.942, with a feedforward Artificial Neural Network (ANN). The performance of the hyb
J. Microw. Optoelectron. Electromagn. Appl.. Publicado em: 2017-09
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4. Neural networks for predicting breeding values and genetic gains
Analysis using Artificial Neural Networks has been described as an approach in the decision-making process that, although incipient, has been reported as presenting high potential for use in animal and plant breeding. In this study, we introduce the procedure of using the expanded data set for training the network. Wealso proposed using statistical parameter
Sci. agric. (Piracicaba, Braz.). Publicado em: 2014-12
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5. A characterization for the constitutive relationships of 42CrMo high strength steel by Artificial Neural Network and its application in isothermal deformation
In hot working process, the prediction of material constitutive relationship can improve the optimization design process. Recently, the artificial neural network models are considered as a powerful tool to describe the elevated temperature deformation behavior of materials. Based on the experimental data from the isothermal compressions of 42CrMo high streng
Mat. Res.. Publicado em: 05/08/2014
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6. Modelo de propagaÃÃo considerando difraÃÃo no topo e nas laterais dos obstÃculos / Propagation model considering diffraction on the top and laterals of obstacles
Este trabalho propÃe um novo Modelo de PropagaÃÃo que considera difraÃÃo lateral em edifÃcios para prediÃÃes de nÃvel de sinal ponto-multiponto. SÃo apresentadas as teorias de difraÃÃo existentes, assim como tÃpicos de anÃlise da propagaÃÃo de sinais eletromagnÃticos e modelos de propagaÃÃo. Com as bases teÃricas sÃo discutidas as premis
Publicado em: 2009
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7. On the prediction of fatigue crack retardation using Wheeler and Willenborg models
The aim of this work is to evaluate the applicability of the Wheeler and Willenborg models to predicting fatigue crack growth retardation in a flash welded structural steel subjected to a single overload during constant amplitude (CA) fatigue crack propagation test. Compact tension specimens, in different microstructural conditions, were subjected to a singl
Materials Research. Publicado em: 2007-06
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8. Avaliação dos modelos de predição de propagação para telefonia móvel celular na cidade do Natal
The development of wireless telecommunication in the last years has been great. It has been taking academics to conceive new ideas and techniques. Their aims are to increase the capacity and the quality of the systems services. Cells that are smaller every time, frequencies that are every time higher and environments that get more and more complex, all those
Publicado em: 2006
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9. Modelagem e medições de ondas de rádio para predição de perda de propagação em ambientes urbanos
Nesta tese novos modelos de predição de perda de percurso de propagação são propostos a partir de técnicas de otimizações recentes e de medições de níveis de potências obtidas para as áreas urbana e suburbana de Natal, cidade do Nordeste Brasileiro. Estes novos modelos são: (i) um modelo estatístico que foi implementado baseado na adição de
Publicado em: 2006
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10. MEDIDAS DE RÁDIO PROPAGAÇÃO EM UHF EM AMBIENTES SUBURBANOS PARA TV DIGITAL: ESTUDO DE COBERTURA PARA RECEPÇÃO FIXA / UHF RADIO PROPAGATION MEASUREMENTS IN SUBURBAN ENVIRONMENTS FOR DIGITAL TV: STUDY OF COVERAGE FOR FIXED RECEPTION
Methods for prediction of propagation loss in the UHF band have great importance for the Digital TV systems sizing. With basis of a great measures campaign in Rio de Janeiro city, this work intendeds to describe the behavior of the signal end to verify the existence of adjusted models to characterize it.
Publicado em: 2005
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11. APPLICATION OF COMPUTATIONALLY-INTENSIVE PROPAGATION MODELS TO THE PREDICTION OF PATH LOSSES DUE TO MOUNTAINOUS TERRAIN IN THE VHF FREQUENCY BAND / APLICAÇÃO DE MODELOS COMPUTACIONALMENTE INTENSIVOS NA PREVISÃO DAS PERDAS DE PROPAGAÇÃO DEVIDAS A TERRENOS IRREGULARES NA FAIXA DE VHF
Os efeitos da difração na propagação de ondas de rádio sobre terreno irregular em VHF e outras bandas a ser usado por futuras aplicações da TV digital são normalmente estimados usando um dos muitos modelos clássicos. Nesta dissertação é feita uma comparação dos erros cometidos na previsão do sinal recebido por três modelos de propagação com
Publicado em: 2005
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12. EFFECTS OF ATMOSPHERIC MULTIPATH IN LINE-OF -SIGHT MICROWAVE SYSTEMS / EFEITOS DE MULTIPERCURSOS ATMOSFÉRICOS EM ENLACES DE MICROONDAS EM VISIBILIDADE
The variations which happen in the troposphere layers throughout the time in relation to the median condition of the signal cause various phenomena that change the received signal level at digital radio relay systems randomly. The random changes are named fading. Fading is normally classified as fast or slow. The former is normally associated with the atmosp
Publicado em: 2004