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ANonmonotone Projected Gradient Method for Multiobjective Problems on Convex Sets

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Journal of the Operations Research Society of China 2024年第2期12卷 410-427页

作者： Gabrie anibal Carrizo Nadia Soledad Fazzio Maria Laura Schuverdt Department of Mathematics National University of the SouthBahia BlancaArgentina Department of Mathematics University of La PlataLa PlataArgentina

In this work we consider an extension of the classical scalar-valued projected gradient method for multiobjective problems on convex *** in Fazzio et al.(Optim Lett 13:1365-1379,2019)a parameter which controls the step length is considered and an updating rule based on the spectral gradient method from the scalar case is *** the present paper,we consider an extension of the traditional nonmonotone approach of Grippo et al.(SIAM J Numer Anal 23:707-716,1986)based on the maximum of some previous function values as suggested in Mita et al.(J Glob Optim 75:539-559,2019)for unconstrained multiobjective optimization *** prove the accumulation points of sequences generated by the proposed algorithm,if they exist,are stationary points of the original *** experiments are reported.

关键词： Multiobjective optimization Projected gradient methods Nonmonotone line search Global convergence

A Simulation Model for Sexual and Vectorial Transmission of Zika Virus(ZIKV)

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Open Journal of Modelling and Simulation 2017年第1期5卷 70-82页

作者： Oscar Arias Manrique Dalia M.munoz Pizza anibal munoz Loaiza Julian A.Olarte Garcia Carlos A.Abello munoz Steven Raigosa Osorio Angie Johanna Osorio Hans Meyer Contreras John F.Arredondo Montoya Grupo de Modelacion Matematica en Epidemiologia(GMME) Facultad de EducacionUniversidad del QuindioQuindioColombia

Nowadays the Zika virus (ZIKV) has been one of the most studied vector-borne diseases due to the considerable outbreaks that have generated around the world as well as due to the new transmission mechanisms and health complications originated. According to statistics of the INS-Colombia for July 2016, 68% of the population infected by ZIKV (confirmed cases) are pregnant women. Furthermore, the Quindío department belongs to the states with more than 50% of the total infected persons being pregnant women. Taking into account those characteristics, a theoretical model is proposed and analyzed to describe the population dynamics considering the sexual and vectorial transmission of ZIKV, with special emphasis in the consequences of the non-vectorial transmission in the population. The obtained results with simulations through the beta parameter indicate that the probability of sexual transmission between susceptible women and infected men points out the importance of campaigns to inculcate prevention measures for the safe sexual relationships between ZIKV infected population.

关键词： ZIKV Model Dynamics Sexual Transmission Vectorial Transmission

External Factors Influencing the Motion of Tectonic Plates

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Open Journal of Earthquake Research 2024年第3期13卷 150-169页

作者： Marilia Hagen anibal Azevedo Instituto de Fsica Universidade do Estado do Rio de Janeiro Rio de Janeiro Brazil Faculdade de Cincias Aplicadas da Unicamp Limeira Brazil

The investigation aims to understand how external forces influence tectonic plate movement, causing earthquakes and volcanic eruptions. Our emphasis was on calculating perigee forces at various moon-Earth distances. Our initial concern is the fluctuating perigee distance between the Moon and Earth. Later, we will cover Earth’s mass fluctuations caused by crustal inhomogeneity. Gravitational force depends on distance and Earth’s mass variations. Wobbling’s Earth and translation around Sun are additional factors. Tidal variations from the Moon trigger subduction zone earthquakes. Volcanoes in the Ring of Fire are influenced by plate movement on fractures and faults.

关键词： Sun Moon-Earth Forces Tectonic Plate Motion Seismic Activity Volcanoes

Investigation of Potential Factors on South Atlantic Magnetic Anomaly

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Open Journal of Earthquake Research 2024年第1期13卷 1-26页

作者： Marilia Hagen anibal Azevedo Instituto de Física Universidade do Estado do Rio de Janeiro Rio de Janeiro Brazil Faculdade de Ciencias Aplicadas da Unicamp Limeira Brazil

The first part of this investigation analyzes the deep earthquake occurrences in Nazca subducting under South America. The depth taken is to get information about possible influences from the unknown materials and formations under the crust. The results revealed the presence of malleable material, which is unbreakable and, therefore, unable to trigger earthquakes. The structure of those elements is diamagnetic, attracting ionized particles from the Van Allen belt region in the ionosphere. The charged particles travel towards Earth’s surface, enhanced during the geomagnetic storms. The South Atlantic Magnetic Anomaly (SAMA) found that the deformation suffered by the anomaly moving from South Africa to South America is, possibly due to a bulge of unknown flexible material buried underneath the oceanic and continental crust. The continental part is strengthening in weakness because the background also has a high amount of diamagnetic material in this region, and it would not happen over the Atlantic Ocean, where part of the deformation is placed.

关键词： Ultra-Deep Earthquakes (UDQ) Diamagnetism South Atlantic Magnetic Anomaly (SAMA)

El Niño-Southern Oscillation (ENSO) Variations and Climate Changes Worldwide

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Atmospheric and Climate Sciences 2024年第2期14卷 233-249页

作者： Marilia Hagen anibal Azevedo (Retired) Instituto de Fí sica Universidade do Estado do Rio de Janeiro Rio de Janeiro Brazil Faculdade de Ciê ncias Aplicadas da Unicamp Limeira Brazil

This investigation aims to study the El-Niño-Southern Oscillation (ENSO) events in these three phases: El Niño, La Niña, and neutral. Warm and cold events relate to the Spring/Summer seasons. This paper will search for connections between the ENSO events and climate anomalies worldwide. There is some speculation that those events would be necessary for the climate anomalies observed worldwide. After analyzing the data from the reports to the ENSO, it shows almost periodicity from 1950-2023. We emphasized the occurrence of El Niño two years, when it was most prominent, and the climate anomalies (following NOAA maps), 2015 and 2023. The results indicated that the observed climate anomalies couldn’t be linked to the abnormal events observed. The worldwide temperatures in those years enhanced mostly in 2023. It shows an abnormal behavior compared with all the years scrutinized and analyzed since the records began. Therefore, there must be unknown factors beyond ENSO that rule the worldwide temperatures and the climate anomalies observed.

关键词： ENSO Southern Oscillation El Niño Climate Anomalies

Performance Improvement of Discrete-time Linear Control Systems Subject to Varying Sampling Rates Using the Tikhonov Regularization Method

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International Journal of Automation and computing 2020年第3期17卷 453-463页

作者： Fernando Agustin Pazos anibal Zanini Amit Bhaya Department of Electronics and Telecommunication Engineering State University of Rio de JaneiroRua São Fransciso Xavier 524Rio de Janeiro 20550-900Brazil Universidad de Buenos Aires-ITHES-UBA-CONICET Departamento de Ingenieria QuimicaPabellón de IndustriasCiudad UniversitariaBuenos Aires C1428EGAArgentina Department of Electrical Engineering Federal University of Rio de JaneiroPEE/COPPE/UFRJRio de Janeiro 21945-970Brazil

Methods to stabilize discrete-time linear control systems subject to variable sampling rates,i.e.,using state feedback controllers,are well known in the *** recent works address the use of the Tikhonov regularization method,originally designed to attenuate the noise effects on ill-posed problems,with the aim of improving performance and stabilizing approximately controllable dynamical *** by these works,we propose the use of a feedback controller designed using the Tikhonov method to regularize discrete-time linear systems subject to varying sampling *** goal is to minimize an error function,thus improving the performance of the closed loop system and reducing the possibility of *** examples show the effectiveness of the proposed method.

关键词： Discrete-time switched systems Tikhonov regularization varying sampling rates discrete-time control systems networked control systems

A PD-Type State-Dependent Riccati Equation With Iterative Learning Augmentation for Mechanical Systems

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IEEE/CAA Journal of Automatica Sinica 2022年第8期9卷 1499-1511页

作者： Saeed Rafee Nekoo JoséÁngel Acosta Guillermo Heredia anibal Ollero GRVC Robotics Lab. Depto de Ingeniería de Sistemas y AutomáticaEscuela Técnica Superior de IngenieríaUniversidad de SevillaSeville 41092Spain

This work proposes a novel proportional-derivative(PD)-type state-dependent Riccati equation(SDRE)approach with iterative learning control(ILC)*** the one hand,the PD-type control gains could adopt many useful available criteria and tools of conventional PD *** the other hand,the SDRE adds nonlinear and optimality characteristics to the controller,i.e.,increasing the stability *** advantages with the ILC correction part deliver a precise control law with the capability of error reduction by *** SDRE provides a symmetric-positive-definite distributed nonlinear suboptimal gain K(x)for the control input law u=–R–1(x)BT(x)K(x)*** sub-blocks of the overall gain R–1(x)BT(x)K(x),are not necessarily symmetric positive definite.A new design is proposed to transform the optimal gain into two symmetric-positive-definite gains like PD-type controllers as u=–KSP(x)e–KSD(x)?.The new form allows us to analytically prove the stability of the proposed learning-based controller for mechanical systems;and presents guaranteed uniform boundedness in finite-time between learning *** symmetric PD-type controller is also developed for the state-dependent differential Riccati equation(SDDRE)to manipulate the final *** SDDRE expresses a differential equation with a final boundary condition,which imposes a constraint on time that could be used for finitetime ***,the availability of PD-type finite-time control is an asset for enhancing the conventional classical linear controllers with this *** learning rules benefit from the gradient descent method for both regulation and tracking *** of the advantages of this approach is a guaranteed-stability even from the first loop of learning.A mechanical manipulator,as an illustrative example,was simulated for both regulation and tracking *** experimental validation was done to show the capability of the system in practice by the implementation of the proposed metho

关键词： Closed-loop iterative learning control(ILC) PD-type SDRE SDDRE symmetric

Impact of Adrenaline or Cortisol Injection on Meat Quality Development of Merino Hoggets

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Journal of Integrative Agriculture 2013年第11期12卷 1931-1936页

作者： Dario G Pighin Sebastian A Cunzolo Maria Zimerman Adriana A Pazos Ernesto Domingo anibal J Pordomingo Gabriela Grigioni Institute of Food Technology National Institute of Agricultural Technology(INTA)De Los Reseros y Las CabaasMorón 1708Argentina National Council of Scientific and Technological Research-CONICET Av.Rivadavia 1917Buenos Aires 1033Argentina Faculty of Agricultural and Food Sciences University of Moron Experimental Station-INTA Bariloche Modesta Victoria 4450San Carlos de Bariloche Río Negro 8400Argentina Institute of Food Technology National Institute of Agricultural Technology(INTA)De Los Reseros y Las Caba asMorón 1708Argentina Experimental Station-INTA Anguil Ruta Nacional No 5 Km.580(6326)La Pampa 6326Argentina

Increased levels of stress hormones in the muscle could lead to post mortem metabolic/structural modiifcations that could be relfected on meat quality. The present study investigated the metabolic effect of either adrenaline or cortisol injected into lambs in order to obtain an animal model of acute stress. Results showed that adrenaline or cortisol injection lead to glucose metabolism and muscle temperature increase. Muscle pH immediately post mortem was affected by adrenaline treatment. Water holding capacity （WHC） of fresh muscle, ifnal muscle pH and temperature registered at 24 h post mortem were not affected by injected hormones. Hardness and adhesiveness of LD muscle evaluated 3 d post mortem tended to increase as a result of adrenaline or cortisol injection. Results demonstrated that injected hormones were able to affect the post mortem muscle biochemistry and the pH/T curve independently of ifnal muscle pH.

关键词： stress hormones muscle metabolism meat quality

Monitoring Heat Waves and Their Impacts on Summer Crop Development in Southern Brazil

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Agricultural Sciences 2014年第4期5卷 353-364页

作者： anibal Gusso Jorge Ricardo Ducati Mauricio Roberto Veronez Victor Sommer Luiz Gonzaga da Silveira Junior Environmental Engineering Vale do Rio dos Sinos University(UNISINOS)Sao LeopoldoBrazil Center for Remote Sensing and Meteorological Research Federal University of Rio Grande do Sul(UFRGS)Porto AlegreBrazil VizLab-Advanced Visualization Laboratory Vale do Rio dos Sinos University(UNISINOS)Sao LeopoldoBrazil Astronomy Department Federal University of Rio Grande do Sul(UFRGS)Porto AlegreBrazil Graduate Program in Geology Vale do Rio dos Sinos University(UNISINOS)Sao LeopoldoBrazil Crop Breeding Foundation(Fundacao Pró-Sementes) Passo FundoBrazil Graduate Program in Applied Computing Vale do Rio dos Sinos University(UNISINOS)São LeopoldoBrazil

Periods in the soybean summer cycle that are sensitive to the occurrence of high temperatures were studied. An analysis was performed on the variability of soybean yields associated with crop canopy temperatures during key development periods. A land surface temperature (LST) data series from MODIS (Moderate Resolution Imaging Spectroradiometer) on the Aqua satellite was processed between 2003 and 2012 that covered the entire state of Rio Grande do Sul, in Brazil. Enhanced vegetation index (EVI) data from MODIS on the Terra satellite were used to monitor the LST during different phenological stages. Spatially interpolated maps of soybean yield distributions were generated using data obtained from Instituto Brasileiro de Geografia e Estatística (IBGE) at state and municipality levels. The results indicate that canopy-LST occurrence in mid-February, during the grain filling, is most correlated to yield reduction (R2 = 0.82 and RMSD = 14.4%). At the state level, the average yield is 2003 kg·ha-1 with a standard deviation of 308 kg·ha-1. The overall average of the canopy-LST is 305.0 K (31.8°C) with a standard deviation of 1.9 K. The slope of the downward linear relationship between canopy-LST and yield was -28.7%. These results indicate that monitoring heat wave events can provide important information for characterising agriculture vulnerability.

关键词： Land Surface Temperature Soybean Remote Sensing Canopy Vegetation Index MODIS Data