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Parameter identification for a damage phase field model using a physics-informed neural network

Theoretical & Applied Mechanics letters 2023年第3期13卷 229-246页

作者： Carlos J.G.Rojas jos l.boldrini Marco l.Bittencourt Department of Integrated System School of Mechanical EngineeringUniversity of CampinasRua Mendeleyev 200CampinasSPZip Code 13083-860Brazil

This work applies concepts of artificial neural networks to identify the parameters of a mathematical model based on phase fields for damage and *** mechanics is the part of the continuum mechanics that models the effects of micro-defect formation using state variables at the macroscopic *** equations that define the model are derived from fundamental laws of physics and provide important relationships among state *** using the model considered in this work produce good qualitative and quantitative results,but many parameters must be adjusted to reproduce certain material *** identification of model parameters is considered by solving an inverse problem that uses pseudo-experimental data to find the best values that fit the *** apply physics informed neural network and combine some classical estimation methods to identify the material parameters that appear in the damage equation of the *** strategy consists of a neural network that acts as an approximating function of the damage evolution with output regularized using the residue of the differential *** stages of optimization seek the best possible values for the neural network and the material *** training alternates between the fitting of only the pseudo-experimental data or the total loss that includes the regularizing *** test the robustness of the method to noisy data and its generalization capabilities using a simple physical case for the damage *** procedure deals better with noisy data in comparison with a more standard PDE-constrained optimization method,and it also provides good approximations of the material parameters and the evolution of damage.

关键词： Deep learning Damage Phase field Parameter fitting Inverse analysis

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Hölder,Sobolev,weak-type and BMO estimates in mixed-norm with weights for parabolic equations

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Science China Mathematics 2021年第1期64卷 129-154页

作者： Pablo Raúl Stinga josé l.Torrea Department of Mathematics Iowa State UniversityAmesIA50011USA Departamento de Matemáticas Universidad Autónoma de MadridMadrid28049Spain

We prove weighted mixed-norm lqt(W2,px)and lqt(C2,αx)estimates for 10,x∈Rn.x∈Rn,The coefficients a(t)=(aij(t))are just bounded,measurable,symmetric and uniformly ***,we show strong,weak type and BMO-Sobolev estimat... 详细信息

We prove weighted mixed-norm lqt(W2,px)and lqt(C2,αx)estimates for 1l∞t(lpx)−BMOt(W2,px)and l∞t(Cαx)−BMOt(C2,xx),and *** formulas for derivatives,for the solutions u=u(t,x)to parabolic equations of the form∂tu−aij(t)∂iju+u=f,t∈,x∈n and for the Cauchy problem{∂tv−aij(t)∂ijv+v=fv(0,x)forfort>0,x∈Rn.x∈Rn,The coefficients a(t)=(aij(t))are just bounded,measurable,symmetric and uniformly ***,we show strong,weak type and BMO-Sobolev estimates with parabolic Muckenhoupt *** is quite remarkable that most of our results are new even for the classical heat equation∂tu−Δu+u=f.

关键词： Calderón-Zygmund parabolic singular integrals weak type and BMO estimates representation formulas parabolic equations mixed-norm Sobolev and Schauder estimates

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Policy Iteration Algorithms for Zero-Sum Stochastic Differential Games with long-Run Average Payoff Criteria

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Journal of the Operations Research Society of China 2014年第4期2卷 395-421页

作者： joséDaniel lópez-Barrientos Faculty of Actuarial Sciences Universidad Ana´huacMe´xico NorteHuixquilucanMexico

This paper studies the policy iteration algorithm(PIA)for zero-sum stochastic differential games with the basic long-run average criterion,as well as with its more selective version,the so-called bias *** system is assumed to be a nondegenerate *** use lyapunov-like stability conditions that ensure the existence and boundedness of the solution to certain Poisson *** also ensure the convergence of a sequence of such solutions,of the corresponding sequence of policies,and,ultimately,of the PIA.

关键词： Ergodic payoff criterion Zero-sum stochastic differential games Policy iteration algorithm Nondegenerate diffusions Poisson equation Schäl convergence Bias game

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Population structure and range expansion:the case of the invasive gastropod Cyclope neritea in northwest Iberian Peninsula

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Integrative Zoology 2012年第3期7卷 286-298页

作者： lucía COUCEIRO lúa lÓPEZ joséMiguel RUIZ Rodolfo BARREIRO Department of Ecology College of ScienceUniversity of A CoruñaA CoruñaSpain

Biotic invasions have a reputation for unpredictable ***,we report how slight changes in human activity responsible for the introduction and range expansion of a non-native mollusk have led to detectable differences in the genetics of the *** neritea is a non-predatory gastropod introduced to 2 areas of the European Atlantic:the northwest Iberian Peninsula(NWIP)and the French Atlantic coast(FAC).Shellfish seabed farming is intense in both areas but focuses on different commercial *** mitochondrial gene sequences,the lower genetic diversity recorded along the NWIP suggests a more homogeneous range of source populations than in the *** FAC,genetic diversity and haplotype composition in the NWIP correlate with the date of first occurrence of *** at each site rather than with geographical *** this pattern evokes the genetic signature expected under a serial-founder colonization model from a single initial enclave,a comparison with samples from potential source populations suggests that the NWIP probably experienced several independent *** jump dispersal pattern of *** in the NWIP,together with the observation that populations established in the same year are genetically undifferentiated,point to human transport as the most plausible explanation for the current range *** evidence for human-mediated dispersal,*** managed to develop a seemingly non-random genetic pattern in the *** is suggested that caution must be exerted when interpreting genetic patterns in invaders.

关键词： alien species Cyclope neritea cytochrome oxidase I genetic geographic pattern population structure

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Carbon Dioxide/Methane Separation by Adsorption on Sepiolite

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Journal of Natural Gas Chemistry 2007年第3期16卷 235-243页

作者： josé A.Delgado María A.Uguina josé l.Sotelo Beatriz Ruíz Marcio Rosário Department of Chemical Engineering Universidad Complutense de Madrid28040Madrid.Spain

In this work, the use of sepiolite for the removal of carbon dioxide from a carbon dioxide/methane mixture by a pressure swing adsorption （PSA） process has been researched. Adsorption equilibrium and kinetics have been measured in a fixed-bed, and the adsorption equilibrium parameters of carbon dioxide and methane on sepiolite have been obtained. A model based on the lDF approximation has been employed to simulate the fixed-bed kinetics, using the langmuir equation to describe the adsorption equilibrium isotherm. The functioning of a PSA cycle for separating carbon dioxide/methane mixtures using sepiolite as adsorbent has also been studied. The experimental results were compared with the ones predicted by the model adapted to a PSA system. Methane with purity higher than 97% can be obtained from feeds containing carbon dioxide with concentrations ranging from 34% to 56% with the proposed PSA cycle. These results suggest that sepiolite is an adsorbent with good properties for its employment in a PSA cycle for carbon dioxide removal from landfill gases.

关键词： carbon dioxide methane sepiolite adsorption fixed-bed pressure swing adsorption

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Global evolution of Equidae and Gomphotheriidae from South America

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Integrative Zoology 2014年第4期9卷 434-443页

作者： josél.PRADO María T.AlBERDI INCUAPA CONICET-UNICENNational University of Central Buenos Aires ProvinceOlavarríaArgentina Department of Paleobiology Museo Nacional de Ciencias NaturalesCSICMadridSpain

The contemporary South American mammalian communities were determined by the emergence of the Isthmus of Panama and by the profound climatic oscillations during the *** and gomphotheres were 2 very conspicuous groups of immigrant mammals from North America that arrived in South America during the *** present study compiles updated data on the phylogeny,systematics and ecology of both groups in South *** horses in South America are represented by 2 genera,Hippidion and Equus,as are the gomphotheres,represented by Cuvieronius and *** genera of horses include small(Hippidion devillei,***,*** and ***)and large forms(Equus neogeus and ***),which dispersed into South America using 2 different *** possible model for this dispersion indicates that the small forms used the Andes corridor,while larger horses dispersed through the eastern route and through some coastal *** the case of gomphotheres,Cuvieronius and Stegomastodon reached South America in 2 independent dispersal events,and Cuvieronius dispersed across the Andean corridor,while large Stegomastodon spread along the eastern *** and gomphotheres present values ofδ^(13)C from woodlands to C4 grass*** present lower values ofδ^(13)C than Equus in the late Pleistocene,whereas the gomphotheres diverge from value ofδ^(18)O,reflecting that Cuvieronius inhabited the Andean corridor and Stegomastodon dispersed through eastern *** gomphothere and horse species recorded in South America became extinct around the time that humans arrived.

关键词： Equidae Gomphotheriidae Plio-Pleistocene South America

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A NEW APPROACH TO SOlVE SYSTEMS OF lINEAR EQUATIONS

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Journal of Computational Mathematics 2001年第4期19卷 445-448页

作者： V á squez, luis V á squez-Poletti, jos é l. Universidad Complutense 西班牙 E-28040 Universidad Pontificia Comillas 西班牙 E-28015

Presents a study which proposed an iterative approach to solve systems of linear equations. Definition of two families of convergent iterative methods; Features of the iterative method; Application of the method to a ... 详细信息

关键词： Iterative method linear systems Classical dynamics.

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Trabectedin therapy as an emerging treatment strategy for recurrent platinum-sensitive ovarian cancer

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Chinese Journal of Cancer 2015年第1期34卷 41-49页

作者： josé Antonio lópez-Guerrero Ignacio Romero Andrés Poveda laboratory of Molecular Biology Fundación Instituto Valenciano de Oncología Clinical Area of Gynecological Cancer Fundación Instituto Valenciano de Oncología

Epithelial ovarian cancer(OC) is a common gynecologic malignancy in women. The standard treatment for OC is maximal cytoreductive surgical debulking followed by platinum-based chemotherapy. Despite the high response rate to primary therapy, approximately 85% of patients will develop recurrent ovarian cancer(ROC). This review identifies the clinical use of trabectedin in the treatment algorithm for ROC, with specific emphasis on platinum-sensitive ROC, for which trabectedin in combination with pegylated liposomal doxorubicin has been approved as a treatment protocol. The main mechanisms of action of trabectedin at the cellular level and in the tumor microenvironment is also discussed as bases for identifying biomarkers for selecting patients who may largely benefit from trabectedin-based therapies.

关键词：治疗方案卵巢癌敏感复发铂疗法恶性肿瘤聚乙二醇化

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Preferences for pre-exposure prophylaxis among U.S. military men who have sex with men:results of an adaptive choice based conjoint analysis study

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Military Medical Research 2022年第2期9卷 141-151页

作者： joséI.Gutierrez Alex Dubov Frederick l.Altice David Vlahov Yale School of Nursing 400 West Campus DriveOrangeCT 06477USA Philip R.lee Institute for Health Policy Studies University of CaliforniaSan Francisco3333 California StSan FranciscoCA 94118USA loma linda University Griggs Hall 11065Loma LindaCA 92350USA Yale School of Medicine Section of Infectious Diseases135 College StreetSuite 323New HavenCT 06510USA Department of Epidemiology-Microbial Diseases Yale School of Public Health60 College StNew HavenCT 06510USA

Background: Pre-exposure prophylaxis(PrEP) prevents human immunodeficiency virus(HIV) infection, but its use remains low among U.S. military men who have sex with men(MSM), likely due to mis-matching with personal preferences. We conducted a study to characterize preferences to PrEP measures within this ***: HIV-negative military MSM were recruited through a closed, lesbian, Gay, Bisexual, and Transgendered(lGBT) military social media group. The survey was anonymous, and consisted of five experimentally varied attributes in service delivery: dosing method, provider type, visit location, lab work evaluation location, and dispensing *** importance and part-worth utility scores were generated using hierarchical bayes(HB) estimation, and the randomized first choice model was used to examine participation interest across eight possible PrEP program ***: A total of 429 participants completed the survey. Among the eight scenarios with varying attributes, the most preferred scenario featured a daily tablet, PrEP injection or implant, along with a military provider, smartphone/telehealth visit, and on-base locations for lab evaluation and medication pick-up. The results also emphasized the importance for providers to be familiar with PrEP prescription knowledge, and to provide interactions sensitive to sexual identity and mental ***: A PrEP program consisting of daily tablet is preferred in military healthcare settings is preferred. longacting implants and injections are also desired.

关键词： Conjoint analysis Pre-exposure prophylaxis Preference Decision science Human immunodeficiency virus Military health Infectious disease

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Alluvial sedimentation and tectonostratigraphic evolution in a narrow extensional zigzag basin margin (northern Teruel Basin, Spain)

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Journal of Palaeogeography 2019年第4期8卷 368-392页

作者： lope Ezquerro Aránzazu luzón josé l.Simón Carlos l.liesa Departamento de Ciencias de la Tierra Facultad de Ciencias Geotransfer Research Group and Instituto de Investigación en Ciencias Ambientales (IUCA) Universidad de Zaragoza

The northern part of the eastern margin of the extensional Neogene Teruel Basin(central-eastern Spain)consists of a non-linear,zigzag fault zone made of alternating ca.2 km long,NNW-SSE trending segments and shorter NNESSW *** outcrop conditions made possible a comprehensive integrated stratigraphic and structural study,especially focused on coarse clastic sediments deposited along the basin ***-exposed stratal relationships with boundary faults,allowed the analysis of tectonic influence on *** deformation includes growth faulting,rollover anticlines,and monoclines and associated onlap stratal terminations,angular unconformities,and other complex growth strata *** of them is the onlap-over-rollover bed arrangement described here for the first time,which reveals the competition between tectonic subsidence and sedimentary ***,the structural inheritance(dense Mesozoic fracture grid)and the dominant,nearly‘multidirectional’(σ1 vertical,σ2≈σ3),Pliocene extensional regime withσ3 close to E-W,are considered to have controlled the margin structure and ***-stratigraphic evolution includes:(i)reactivation of inherited NNW-SSE faults and development of W-SW-directed small alluvial fans(SAF)while NNE-SSW segments acted as gentle relay ramp zones;(ii)progressive activation of NNE-SSW faults and development of NW-directed very small alluvial fans(VSAF);during stages i and ii sediments were trapped close to the margin,avoiding widespread progradation;(iii)linking of NNW-SSE and NNE-SSW structural segments,overall basin sinking and widespread alluvial progradation;(iv)fault activity attenuation and alluvial *** particular structure and kinematic evolution of this margin controlled alluvial system *** of alluvial fans,directly set up at the border faults,was conditioned by the narrowness of the margin,small catchment areas,and proximity between faults,which prevented the development of l

关键词： Extensional basin Alluvial fan Stratal stacking pattern Structural inheritance Fault linkage

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