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Proximal Methods with Bregman Distances to Solve VIP on Hadamard Manifolds with Null Sectional Curvature

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Journal of the Operations Research Society of China 2021年第3期9卷 499-523页

作者： erik Alex Papa Quiroz paulo Roberto Oliveira Universidad Nacional Mayor de San Marcos Universidad Privada del NorteLimaPeru PeSC-COPPe Federal University of Rio de JaneiroRio de Janeiro CEP 21941-972Brazil

We present an extension of the proximal point method with Bregman distances to solve variational inequality problems(VIP)on Hadamard manifolds with null sectional *** some natural assumptions,as for example,the existence of solutions of the VIP and the monotonicity of the multivalued vector field,we prove that the sequence of the iterates given by the method converges to a solution of the ***,this convergence is linear or superlinear with respect to the Bregman distance.

关键词： Proximal point methods Hadamard manifolds Bregman distances Variational inequality problems Monotone vector field

Changes in the Dynamics of a Rössler Oscillator by an external Forcing

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Chinese Physics Letters 2013年第3期30卷 22-25页

作者： Amanda C.Mathias paulo C.Rech Departamento de Física Universidade do Estado de Santa Catarina89219-710 JoinvilleBrazil

We report some results indicating changes in the observed dynamics of the Rössler model under the influence of external sinusoidal *** varying the control parameters of the external sinusoidal forcing,namely the amplitude and the angular frequency,we show,through numerical simulations which include parameter planes and Lyapunov exponents,that the external forcing can produce both chaos-order and order-chaos *** also show that the sinusoidal forcing may generate hyperchaos.

关键词： chaos sinusoidal transitions

Chaos Suppression in a Sine Square Map through Nonlinear Coupling

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Chinese Physics Letters 2011年第11期28卷 45-48页

作者： eduardo L.Brugnago paulo C.Rech Departamento de Física Universidade do Estado de Santa Catarina89223-100 JoinvilleBrazil

We study a pair of nonlinearly coupled identical chaotic sine square *** specifically,we investigate the chaos suppression associated with the variation of two ***-dimensional parameter-space regions where the chaotic dynamics of the individual chaotic sine square map is driven towards regular dynamics are ***,the dynamics of the coupled system is numerically characterized as the parameters are changed.

关键词： chaotic dynamics Chaos

3D Progressive Damage Based Macro-Mechanical Fe Simulation of Machining Unidirectional FRP Composite

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Chinese Journal of Mechanical engineering 2018年第3期31卷 128-143页

作者： Yan-Li He Joao-paulo Davim Hong-Qian Xue Key Laboratory of Contemporary Design and Integrated Manufacturing Technology of Ministry of education School of Mechanical EngineeringNorthwestern Polytechnical University Department of Mechanical engineering University of AveiroCampus Santiago

Finite element(Fe) simulation is a powerful tool for investigating the mechanism of machining fiber?reinforced polymer composite(FRP). However in existing Fe machining simulation works,the two?dimensional(2 D) progressive damage models only describe material behavior in plane stress,while the three?dimensional(3 D) damage models always assume an instantaneous sti ness reduction pattern. So the chip formation mechanism of FRP under machin?ing is not fully analyzed in general stress state. A 3 D macro?mechanical based Fe simulation model was developed for the machining of unidirectional glass fiber reinforced plastic. An energy based 3 D progressive damage model was proposed for damage evolution and continuous sti ness degradation. The damage model was implemented for the Hashin?type criterion and Maximum stress criterion. The influences of the failure criterion and fracture energy dissipa?tion on the simulation results were studied. The simulated chip shapes,cutting forces and sub?surface damages were verified by those obtained in the reference experiment. The simulation results also show consistency with previous 2 D Fe models in the reference. The proposed research provides a model for simulating FRP material behavior and the machining process in 3 D stress state.

关键词： FRP Macro mechanical Machining Finite element Progressive damage

Nutrient content affecting Spodoptera frugiperda and Dalbulus maidis occurrence in corn

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Insect Science 2007年第2期14卷 117-123页

作者： CRISTINA SCHeTINO BASTOS JOAO CARLOS CARDOSO GALVAO MARCeLO COUTINHO PICANCO paulo ROBeRTO GOMeS PeReIRA paulo ROBeRTO CeCON eMBRAPA/Algodao Centenário Campina Grande PB Brazil Departamento de Fitotecnia Universidade Federal de Vicosa (UFV) Vicosa MG Brazil. Departamento de Biologia Animal Universidade Federal de Vicosa (UFV) Vicosa MG Brazil. Departamento de Informática Campus Universitário Universidade Federal de Vicosa (UFV) Vicosa MG Brazil.

This work aims to study the effect of the nutrient contents in the leaves of corn on the incidence of Spodopterafrugiperda （Smith）（Lepidoptera： Noctuidae） and Dalbulus maidis （Delong ＆ Wolcott）（Homoptera： Cicadellidae）. The treatments were represented by unfertilized corn plants and corn plants fertilized with 250 kg of the formulation 4-14-8 （N- P-K）＋ 100 kg of ammonium sulfate （AS）/ha and 500 kg of the formulation 4-14-8 （N-P-K）＋200 kg of AS/ha, arranged in randomized blocks with four replicates. Attacks by S. frugiperda and D. maidis were higher as the nitrogen, sulfur, calcium and copper content in the leaves of corn increased. The effects of calcium and copper found in this study were not consistent with that of lower susceptibility associated with higher levels of these nutrients mentioned in the literature. We believe that there was a cumulative effect of the nutrients altogether, building up a nutritiously better vegetable which in turn had less reserve for defense, or that the content of both nutrients in the leaves were not high enough to induce such effects.

关键词： calcium copper corn cicada fall armyworm fertilization nitrogen sulfur

A Parameter-Space Analysis of the Rikitake System

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Chinese Physics Letters 2013年第12期30卷 13-16页

作者： Rodrigo A.da Silva paulo C.Rech Departamento de Física Universidade do Estado de Santa Catarina89219-710 JoinvilleBrazil

We investigate analytically and numerically the dynamics of the Rikitake *** Routh–Hurwitz criterion is used to study the stability of the equilibrium points of the differential equation system model,as functions of two *** dynamics of the model are numerically studied using diagrams that associate colors to the largest Lyapunov exponent value,in two-dimensional parameter ***,phase-space plots and bifurcation diagrams are used to distinguish periodic and chaotic attractors.

关键词： bifurcation exponent chaotic

Laparoscopic resection for hepatocellular carcinoma: eastern and western experiences

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Chinese Journal of Cancer Research 2014年第3期26卷 234-236页

作者： paulo Herman Fabricio Ferreira Coelho Liver Surgery Unit Department of GastroenterologyUniversity of Sao Paulo Medical School

Hepatocellular carcinoma （HCC） is the most common primary liver cancer （1）. The incidence is rising in the last decades due to many factors, especially hepatitis C, alcoholic liver disease and non-alcoholic steatohepatitis. Moreover, the introduction of screening programs in patients with chronic liver disease has led to an increase in HCC diagnosis （1,2）. In the western world, 80% to 90% of HCC eases occur in patients with liver cirrhosis （3） while this proportion is lower in some regions in Asia and sub-Saharian Africa, where hepatitis B remains as an important etiologic factor for chronic liver disease （2,4）. In 1990, the annual world frequency of HCC was 437,000 cases/year （1）, and in 2012 the number reached 782,200 cases/year being responsible for 746,000 deaths （5）. Nowadays, HCC represents the 6th most frequent neoplastic disease in the world and the 3rd in mortality （5）.

关键词： HCC eastern and western experiences Laparoscopic resection for hepatocellular carcinoma

Addressing the CQI feedback delay in 5G/6G networks via machine learning and evolutionary computing

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Intelligent and Converged Networks 2022年第3期3卷 271-281页

作者： Andson Balieiro Kelvin Dias paulo Guarda Centro de Informática(CIn) Universidade Federal de PernambucoRecife 50740-560Brasil Motorola Mobility Mogi Mirim 13800-206Brazil

5G networks apply adaptive modulation and coding according to the channel condition reported by the user in order to keep the mobile communication ***,the delay incurred by the feedback may make the channel quality indicator(CQI)*** paper addresses this issue by proposing two approaches,one based on machine learning and another on evolutionary computing,which considers the user context and signal-to-interference-plus-noise ratio(SINR)besides the delay length to estimate the updated SINR to be mapped into a CQI *** proposals are designed to run at the user equipment(Ue)side,neither requiring any change in the signalling between the base station(gNB)and Ue nor overloading the *** are evaluated in terms of mean squared error by adopting 5G network simulation data and the results show their high accuracy and feasibility to be employed in 5G/6G systems.

关键词： channel quality indicator(CQI)feedback delay 5G/6G networks machine learning evolutionary computing

Development and assessment of artificial neural network models for direct normal solar irradiance forecasting using operational numerical weather prediction data

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energy and AI 2024年第1期15卷 88-101页

作者： Sara Pereira paulo Canhoto Rui Salgado Institute of earth Sciences University ofÉvoraRua Romãao Ramalho 597000-671ÉvoraPortugal Department of Mechatronics engineering University of´EvoraRua Romãao Ramalho 597000-671ÉvoraPortugal Physics Department University of´EvoraRua Romãao Ramalho 597000-671ÉvoraPortugal

Accurate operational solar irradiance forecasts are crucial for better decision making by solar energy system operators due to the variability of resource and energy *** numerical weather prediction(NWP)models can forecast solar radiation variables,they often have significant errors,particularly in the direct normal irradiance(DNI),which is especially affected by the type and concentration of aerosols and *** paper presents a method based on artificial neural networks(ANN)for generating operational DNI forecasts using weather and aerosol forecasts from the european Center for Medium-range Weather Forecasts(eCMWF)and the Copernicus Atmospheric Monitoring Service(CAMS),*** ANN models were designed:one uses as input the predicted weather and aerosol variables for a given instant,while the other uses a period of the improved DNI forecasts before the forecasted *** models were developed using observations for the location of´evora,Portugal,resulting in 10 min DNI forecasts that for day 1 of forecast horizon showed an improvement over the downscaled original forecasts regarding R2,MAe and RMSe of 0.0646,21.1 W/m^(2)and 27.9 W/m^(2),*** model was also evaluated for different timesteps and locations in southern Portugal,providing good agreement with experimental data.

关键词： Solar radiation Solar energy Numerical weather prediction Artificial neural network Operational forecasting