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A Proof of Wedderburn＇s Theorem

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Algebra Colloquium 2015年第4期22卷 603-606页

作者： josé antonio Cuenca Mira Departamento de álgebra Geometría y Topología Facultad de Ciencias Universidad de Málaga 29071 Málaga Spain

In this note we first introduce the finite weak Herstein condition, which is a property that holds for every finite field. For a field F satisfying the finite weak Herstein condition, we then characterize whether all the finite-dimensional division F-algebras are commutative. This gives an alternate proof of Wedderburn＇s Theorem.

关键词： division algebra finite-dimensional algebra finite field Galois extension

Gravitational waves from compact objects

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Research in Astronomy and Astrophysics 2010年第11期10卷 1071-1099页

作者： josé antonio de Freitas Pacheco University of Nice-Sophia Antipolis Observatoire de la Cote d'Azur Laboratoire Cassiopée-UMR 6202 BP 4229-F606304-Nice Cedex 4-France

Large ground-based laser beam interferometers are presently in operation both in the USA （LIGO） and in Europe （VIRGO） and potential sources that might be detected by these instruments are revisited. The present generation of detectors does not have a sensitivity high enough to probe a significant volume of the universe and, consequently, predicted event rates are very low. The planned advanced generation of interferometers will probably be able to detect, for the first time, a gravitational sig- nal. Advanced LIGO and EGO instruments are expected to detect few （some）： binary coalescences consisting of either two neutron stars, two black holes or a neutron star and a black hole. In space, the sensitivity of the planned LISA spacecraft constellation will allow the detection of the gravitational signals, even within a ＂pessimistic＂ range of possible signals, produced during the capture of compact objects by supermassive black holes, at a rate of a few tens per year.

关键词： gravitational waves -- neutron stars -- black holes

Parameter Estimation for Hot-spot Thermal Model of Power Transformers Using Unscented Kalman Filters

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Journal of Modern Power Systems and Clean Energy 2023年第2期11卷 634-642页

作者： MiguelÁngel González-Cagigal joséantonio Rosendo-Macías antonio Gómez-Expósito Department of Electrical Engineering University of SevilleSevilleSpain ENGREEN Laboratory of Engineering for Energy and Environmental Sustainability SevilleSpain

This paper presents a parameter estimation technique for the hot-spot thermal model of power *** proposed technique is based on the unscented formulation of the Kalman filter,jointly considering the state variables and parameters of the dynamic thermal model.A two-stage estimation technique that takes advantage of different loading conditions is developed,in order to increase the number of parameters which can be *** results are presented,which show that the observable parameters are estimated with an error of less than 3%.The parameter estimation procedure is mainly intended for factory testing,allowing the manufacturer to enhance the thermal model of power transformers and,therefore,its customers to increase the lifetime of these *** proposed technique could be additionally considered in field applications if the necessary temperature measurements are available.

关键词： Parameter estimation power transformer unscented Kalman filter thermal model

Miscibility of Poly(hydroxybutyrate)/Poly(vinyl alcohol)Melt Blends Plasticized With Glycerol

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Journal of Renewable Materials 2019年第4期7卷 325-333页

作者： Deliane da Silva Cabral antonio joséFelix Carvalho Department of Materials Engineering São Carlos School of EngineeringUniversity of São PauloAv.João Dagnone110013563-120São Carlos-SP-Brazil

Poly(hydroxybutyrate)/poly(vinyl alcohol)(PHB/PVA)blends plasticized with glycerol were prepared by melt blending of PHB and glycerol plasticized *** PHB/PVA-glycerol compositions were 90:10,75:25 and 50:50 w/w,being the concentration of glycerol in the PVA mixture of 10 wt%.The blends were characterized by infrared spectroscopy,dynamic-mechanical thermal analysis,and scanning electron microscope of the fragile fractured *** results showed one single phase blend,indicating miscibility corroborated by the presence of a single glass transition *** blending method proved to be an efficient way to tune PHB properties keeping its biodegradable nature since both PVA and glycerol are fully biodegradable materials.

关键词： Blend miscibility melt processing poly(hydroxybutyrate) poly(vinyl alcohol)

An improved flexible tolerance method for solving nonlinear constrained optimization problems:Application in mass integration

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Chinese Journal of Chemical Engineering 2017年第5期25卷 617-631页

作者： Alice Medeiros Lima Wu Hong Kwong antonio josé Goncalves Cruz Chemical Engineering Graduate Program Federal University of Sao Carlos Department of Chemical Engineering Department of Chemical Engineering Federal University of Sao Carlos

This paper proposes the use of the flexible tolerance method(FTM) modified with adaptive Nelder–Mead parameters and barrier to solve constrained optimization problems. The problems used to analyze the performance of the methods were taken from G-Suite functions, and the methods with the best performance were applied in mass integration problems. Four methods were proposed:(1) flexible tolerance method(FTM) using adaptive parameters(FTMA),(2) flexible tolerance method with scaling(FTMS) and with adaptive parameters(FTMAS),(3) FTMS including the barrier modification(MFTMS) and(4) MFTMS hybridized with PSO(MFTMS-PSO). The success rates of these methods were 100%(MFTMS), 85%(MFTMS-PSO), 40%(FTMAS) and 30%(FTMA).Numerical experiments indicated that the MFTMS could efficiently and reliably improve the accuracy of global optima. In mass integration, the method was able, from current process situation, to reach the optimum process configuration that includes integration issues, which was not possible using FTM in its standard formulation. The hybridization of FTMS with PSO(without barrier), FTMS-PSO, was also able to solve mass integration problems efficiently.

关键词： Flexible tolerance method Adaptive parameters Scaling Constrained optimization Barrier PSO Mass integration

Appraising trapping efficiency of vegetative barriers in agricultural landscapes:Strategy based on a probabilistic approach based on a review of available information

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International Soil and Water Conservation Research 2024年第3期12卷 615-634页

作者： josé-antonio Muñoz Gema Guzmán María-Auxiliadora Soriano josé A.Gómez Institute for Sustainable Agriculture(IAS)-CSIC Cordoba14004Spain Andalusian Institute of Agricultural and Fisheries Research and Training(IFAPA) Granada18004Spain Agronomy Department(DAUCO) University of CordobaCordoba14071Spain

Vegetative barriers have proven their effectiveness in controlling water erosion and enhancing other ecosystem services in agricultural *** characteristic has led to the conservation and promotion of vegetative barriers as landscape elements by the Common Agricultural Policy and other policy *** reviews have dealt with the trapping efficiency of vegetated barriers,although they usually focus on studies from humid climates where their implantation and survival are more ***,vegetated barriers are also an attractive alternative in arid and semi-arid *** limit competition for water and nutrients with crops to a reduced area compared to other best management practices,such as cover *** study presents a review of trapping efficiency of sediment,runoff,and nutrients(P and N)by vegetative barriers in regions of humid and arid,and semi-arid,climates,and a strategy based on sediment trapping efficiency probability,which in turn is based on the results obtained from our *** types of independent variables were grouped and identified for the review:related to the vegetative barrier dimension(buffer width,slope of the plot,and buffer area ratio),and related to the experimental conditions(type of vegetation in the buffer,soil protection of the non-buffered area,type of climate,type of experimental measurement and origin of rainfall).An explor-atory analysis evaluated the significance of the experimental variables,which identified the need to focus on experiments under natural rainfall since those carried out with simulated rainfall presented statis-tically significant *** general,average trapping efficiencies for runoff and sediment were 40.1 and 62.6%,*** nutrients,values of trapping efficiencies had an average of 44.9%for phosphorus and 38.4%for *** and sediment trapping efficiency in arid and semi-arid re-gions tended to be higher than in humid *** dimensional

关键词： Connectivity Sediment transport Runoff Nutrients Experimental plots Buffer strip

An update on iron physiology

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World Journal of Gastroenterology 2009年第37期15卷 4617-4626页

作者： Manuel Muoz Isabel Villar josé antonio García-Erce Transfusion Medicine School of Medicine University of Málaga Málaga 29071 Spain Department of Hospital Pharmacy University Hospital Miguel Servet Zaragoza 50009 Spain Hematology and Hemotherapy University Hospital Miguel Servet Zaragoza 50009 Spain

Iron is an essential micronutrient, as it is required for adequate erythropoietic function, oxidative metabolism and cellular immune responses. Although the absorption of dietary iron (1-2 mg/d) is regulated tightly, it is just balanced with losses. Therefore, internal turnover of iron is essential to meet the requirements for erythropoiesis (20-30 mg/d). Increased iron requirements, limited external supply, and increased blood loss may lead to iron deficiency (ID) and iron-deficiency anemia. Hepcidin, which is made primarily in hepatocytes in response to liver iron levels, inflammation, hypoxia and anemia, is the main iron regulatory hormone. Once secreted into the circulation, hepcidin binds ferroportin on enterocytes and macrophages, which triggers its internalization and lysosomal degradation. Thus, in chronic inflammation, the excess of hepcidin decreases iron absorption and prevents iron recycling, which results in hypoferremia and iron-restricted erythropoiesis, despite normal iron stores (functional ID), and anemia of chronic disease (ACD), which can evolve to ACD plus true ID (ACD + ID). In contrast, low hepcidin expression may lead to iron overload, and vice versa. Laboratory tests provide evidence of iron depletion in the body, or reflect iron-deficient red cell production. The appropriate combination of these laboratory tests help to establish a correct diagnosis of ID status and anemia.

关键词： Iron metabolism Iron deficiency Functionaliron deficiency, Hepcidin Anemia of chronic disease

Thermal and Mechanical Properties of Thermoplastic Starch and Poly(Vinyl Alcohol-Co-Ethylene)Blends

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Journal of Renewable Materials 2019年第3期7卷 245-252页

作者： Ana Clara Lancarovici Alves Rafael Grande antonio josé Felix Carvalho Department of Materials Engineering Sao Carlos School of EngineeringUniversity of Sao PauloAv.Joao Dagnone110013563-120Sao Carlos-SP-Brazil

The interest in thermoplastic starch(TPS)as a substitute material to replace conventional thermoplastics continues especially due its biodegradability,availability,low cost and because it is obtained from renewable ***,its poor mechanical properties and its high sensitivity to humidity have limited its use in several ***,the copolymer poly(ethylene-co-vinyl alcohol)(EVOH),with two different ethylene contents,27 and 44 mol%were blended with TPS by extrusion in order to overcome these *** obtained blends were characterized by thermogravimetric analysis(TGA),differential scanning calorimetry(DSC),mechanical tensile testing,Scanning Electron Microscopy(SEM)and moisture absorption *** addition of EVOH copolymer did not significantly changed the thermal stability of TPS,however it increased the tensile strength in 65%when compared to *** morphology of the blends did not showed two distinct phases,an indication of miscibility or partial miscibility of the components.A decrease of moisture absorption was obtained by the addition of EVOH and is more pronounced for the EVOH with 44% of ethylene.

关键词： Thermoplastic starch EVOH polymer blends thermal properties of polymers mechanical properties of polymers

Comparing Fine-Tuning, Zero and Few-Shot Strategies with Large Language Models in Hate Speech Detection in English

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2849-2868页

作者： Ronghao Pan joséantonio García-Díaz Rafael Valencia-García Departamento de Informática y Sistemas Universidad de MurciaCampus de EspinardoMurcia30100Spain

Large Language Models(LLMs)are increasingly demonstrating their ability to understand natural language and solve complex tasks,especially through text *** of the relevant capabilities is contextual learning,which involves the ability to receive instructions in natural language or task demonstrations to generate expected outputs for test instances without the need for additional training or gradient *** recent years,the popularity of social networking has provided a medium through which some users can engage in offensive and harmful online *** this study,we investigate the ability of different LLMs,ranging from zero-shot and few-shot learning to *** experiments show that LLMs can identify sexist and hateful online texts using zero-shot and few-shot approaches through information ***,it is found that the encoder-decoder model called Zephyr achieves the best results with the fine-tuning approach,scoring 86.811%on the Explainable Detection of Online Sexism(EDOS)test-set and 57.453%on the Multilingual Detection of Hate Speech Against Immigrants and Women in Twitter(HatEval)***,it is confirmed that the evaluated models perform well in hate text detection,as they beat the best result in the HatEval task *** error analysis shows that contextual learning had difficulty distinguishing between types of hate speech and figurative ***,the fine-tuned approach tends to produce many false positives.

关键词： Hate speech detection zero-shot few-shot fine-tuning natural language processing