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A nETWORK AnALYSIS OF THE 2010 FIFA WORLD CUP CHAMPIOn TEAM PLAY

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Journal of Systems Science & Complexity 2013年第1期26卷 21-42页

作者： COTTA carlos MORA Antonio M MERELO Juan Julin MERELO-MOLInA Cecilia Department of Computer Science University of Mlaga Department of Architecture and Computer Technology University of Granada

This paper analyzes the network of passes among the players of the Spanish team during the last FIFA World Cup 2010,where they emerged as the champion,with the objective of explaining the results obtained from the behavior at the complex network *** team is considered a network with players as nodes and passes as(directed) edges.A temporal analysis of the resulting passes network is also done,looking at the number of passes,length of the chain of passes,and to network measures such as player centrality and clustering *** of the last three matches(the decisive ones) indicate that the clustering coefficient of the pass network remains high,indicating the elaborate style of the Spanish *** effectiveness of the opposing team in negating the Spanish game is reflected in the change of several network measures over time,most importantly in drops of the clustering coefficient and passing length/speed,as well as in their being able in removing the most talented players from the central positions of the ***'s ability to restore their combinative game and move the focus of the game to offensive positions and talented players is shown to tilt the balance in favor of the Spanish team.

关键词： Complex network complex systems FIFA World Cup football La Roja network analysis soccer Spanish team sports.

On the non-evolution of the dependence of black hole masses on bolometric luminosities for QSOs

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Research in Astronomy and Astrophysics 2012年第3期12卷 249-259页

作者： Martín López-Corredoira carlos M. Gutirrez Instituto de Astrofísica de Canarias Departamento de Astrofísica Universidad de La Laguna

There are extremely luminous quasi stellar objects （QSOs） at high redshift which are absent at low redshift. The lower luminosities at low redshifts can be understood as the external manifestation of either a lower Eddington ratio or a lower mass. To distinguish between both effects, we determine the possible dependence of masses and Eddington ratios of QSOs with a fixed luminosity as a function of redshifts; this avoids the Malmquist bias or any other selection effect. For the masses and Eddington ratios derived for a sample of QSOs in the Sloan Digital Sky Survey, we model their evolution by a double linear fit separating the dependence on redshifts and luminosities. The validity of the fits and possible systematic effects were tested by the use of different estimators of masses or bolometric luminosities, and possible intergalactic extinction effects. The results do not show any significant evolution of black hole masses or Eddington ratios for equal luminosity QSOs. The black hole mass only depends on the bolometric luminosity without significant dependence on the redshift as （M BH/10 9 M ）≈ 3.4 （L bol/10 47 erg s-1）0.65 on average for z ≤ 5. This must not be confused with the possible evolution in the formation of black holes in QSOs. The variations of the environment might influence the formation of the black holes but not their subsequent accretion. It also leaves a question to be solved： Why are there not QSOs with very high mass at low redshift？ A brief discussion of the possible reasons for this is tentatively pointed out.

关键词： accretion—methods: statistical—quasars: general

Short and Long-Term Time Series Forecasting Stochastic Analysis for Slow Dynamic Processes

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Applied Mathematics 2019年第8期10卷 704-717页

作者： Julián Pucheta carlos Salas Martín herrera Cristian Rodriguez Rivero Gustavo Alasino FCEFyn-Universidad nacional de Córdoba Córdoba Argentina FTyCA-Universidad nacional de Catamarca Catamarca Argentina Cristian University of California Los Angeles USA Universidad Torcuato Di Tella Buenos Aires Argentina

This paper intends to develop suitable methods to provide likely scenarios in order to support decision making for slow dynamic processes such as the underlying of agribusiness. A new method to analyze the short- and long-term time series forecast and to model the behavior of the underlying process using nonlinear artificial neural networks (Ann) is presented. The algorithm can effectively forecast the time-series data by stochastic analysis (Monte Carlo) of its future behavior using fractional Gaussian noise (fGn). The algorithm was used to forecast country risk time series for several countries, both for short term that is 30 days ahead and long term 350 days ahead scenarios.

关键词： Stochastic Analysis Time Series Forecasting Decision Making Dynamic Process Process Modelling

Brent *** Texas Intermediate in the US petro derivatives price formation

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Petroleum Science 2024年第1期21卷 729-739页

作者： Alejandro Almeida Antonio A.Golpe Juan Manuel Martín-Alvarez Jose carlos Vides Universidad Internacional de La Rioja Department of Quantitative Methods for Economics and BusinessLa RiojaSpain University of Huelva Department of Economics and Centro de Estudios Avanzados en FisicaMatematicas y Computacion and ICEIHuelvaSpain Complutense University of Madrid Department of Applied and Structural Economics and History and ICEIMadridSpain

In this paper,we apply the spatial panel model to explore the relationship between the dynamic of two types of crude oil prices(WTI and Brent crude oil)and their refined products over *** the turbulent months of 2011,when Cushing Oklahoma had reached capacity and the crude oil export ban removal in 2015 as breakpoints,we apply this method both in the full sample and the three resultant ***,results suggest our results show that both WTI and Brent display very similar behaviour with the refined ***,when attending to each regime,results derived from the first and third regimes are quite similar to the full sample ***,during the second regime,Brent crude oil became the benchmark in the petrol market,and it influenced the distillate ***,our model can let us determine the price-setters and price-followers in the price formation mechanism through refined *** results possess important considerations to policymakers and the market participants and the price formation.

关键词： Crude oil prices Spatial panel model Refined products Price formation

End-to-end differentiable learning of turbulence models from indirect observations

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Theoretical & Applied Mechanics Letters 2021年第4期11卷 205-212页

作者： carlos A.Michelén Strofer Heng Xiao Kevin T.Crofton Department of Aerospace and Ocean Engineering Virginia TechBlacksburgVirginiaUnited States

The emerging push of the differentiable programming paradigm in scientific computing is conducive to training deep learning turbulence models using indirect *** paper demonstrates the viability of this approach and presents an end-to-end differentiable framework for training deep neural networks to learn eddy viscosity models from indirect observations derived from the velocity and pressure *** framework consists of a Reynolds-averaged navier–Stokes(RAnS)solver and a neuralnetwork-represented turbulence model,each accompanied by its derivative *** computing the sensitivities of the indirect observations to the Reynolds stress field,we use the continuous adjoint equations for the RAnS equations,while the gradient of the neural network is obtained via its built-in automatic differentiation *** demonstrate the ability of this approach to learn the true underlying turbulence closure when one exists by training models using synthetic velocity data from linear and nonlinear *** also train a linear eddy viscosity model using synthetic velocity measurements from direct numerical simulations of the navier–Stokes equations for which no true underlying linear closure *** trained deep-neural-network turbulence model showed predictive capability on similar flows.

关键词： Turbulence modeling Machine learning Adjoint solver Reynolds-averaged navier-Stokes equations

Residential end-uses disaggregation and demand response evaluation using integral transforms

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Journal of Modern Power Systems and Clean Energy 2017年第1期5卷 91-104页

作者： Antonio GABALDón Roque MOLInA Alejandro MARín-PARRA Sergio VALERO-VERDú carlos áLVAREZ ETS de Ingenierı´a Industrial Universidad Polite´cnica de CartagenaDr.Fleming s/n30202 CartagenaSpain EPS de Elche Universidad Miguel Herna´ndezElcheSpain Institute for Energy Engineering Universidad Polite´cnica de ValenciaValenciaSpain

Demand response is a basic tool used to develop modern power systems and electricity markets. Residential and commercial segments account for 40%–50% of the overall electricity demand. These segments need to overcome major obstacles before they can be included in a demand response portfolio. The objective of this paper is to tackle some of the technical barriers and explain how the potential of enabling technology(smart meters) can be harnessed, to evaluate the potential of customers for demand response(end-uses and their behaviors) and,moreover, to validate customers’ effective response to market prices or system events by means of non-intrusive methods. A tool based on the Hilbert transform is improved herein to identify and characterize the most suitable loads for the aforesaid purpose, whereby important characteristics such as cycling frequency, power level and pulse width are identified. The proposed methodology allows the filtering of aggregated load according to the amplitudes of elemental loads, independently of the frequency of their behaviors that could be altered by internal or external inputs such as weather or demand response. In this way, the assessment and verification of customer response can be improved by solving the problem of load aggregation with the help of integral transforms.

关键词： Demand response Hilbert transform Load monitoring Instantaneous frequency Aggregation Smart meters

Existence of Semiclassical States for a Quasilinear Schr?dinger Equation on R^n with Exponential Critical Growth

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Acta Mathematica Sinica,English Series 2016年第11期32卷 1279-1296页

作者： Shao Jun LI carlos A. SAnTOS Min Bo YAnG Department of Mathematics Zhejiang Normal UniversityJinhua 321004P.R.China Universidade de Brasilia Departamento de Matematica70910-900 BrasiliaDFBrazil

We study a quasilinear Schrodinger equation {-εn△nu＋V（x）｜u｜n-2= Q（x）f（u） in R^n,0〈u∈W1,n（Rn）,u（x）^｜x｜→∞0,where V, Q are two continuous real functions on R^n and c 〉 0 is a real parameter. Assume that the nonlinearity f is of exponential critical growth in the sense of Trudinger-Moser inequality, we are able to establish the existence and concentration of the semiclassical solutions by variational methods. Keywords Exponential critical growth, semiclassical solutions, variational methods

关键词： Exponential critical growth semiclassical solutions variational methods

Avian responses to an extreme weather event:The case of the‘Filomena’snowstorm in Madrid(central Spain)

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Avian Research 2024年第2期15卷 180-186页

作者： carlos Lazaro carlos Sanchez-García Fabian Casas E.Jorge Tizado Department of Research Fundacion Artemisan13001 Ciudad RealSpain Department of Zoology Faculty of SciencesUniversity of GranadaGranadaSpain Department of Biodiversity and Environmental Management Universidad de Leon24401 PonferradaSpain

Cold spells and severe weather may have detrimental effects in wild birds,but owing to the stochastic nature of these events,it is not always possible to measure their *** January 2021,a strong snowstorm known as‘Filomena’affected Spain,mainly the region of Madrid(Central Spain),which was fully covered with snow and suffered freezing temperatures for a *** bird surveys conducted in the winter-spring of 2020 and 2021(before and after Filomena)at same locations,we addressed the possible impact of the cold spell in three widespread gamebirds:Wood Pigeon(Columba palumbus),Eurasian Magpie(Pica pica)and Red-legged Partridge(Alectoris rufa).no significant abundance differences were found between years for none of the species and hunting pressure was only significantly reduced for Partridges,hence this species may have been negatively affected by *** suggest that in response to Filomena,Pigeons conducted partial migration in search of better conditions,while Magpies aggregated in certain areas of Madrid and Partridges endured the harsh conditions within their home *** results highlight the importance to alleviate negative impacts of extreme weather events in wild birds through management actions,especially for sedentary species.

关键词： Alectoris rufa Climate change Cold spell Columba palumbus Migration Pica pica Winter

Landform Instability and Land-use Dynamics in Tropical High Mountains, Central Mexico

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Journal of Mountain Science 2012年第3期9卷 414-430页

作者： GARCíA-ROMERO Arturo ACEVES-QUESADA José Fernando ARREDOnDO-LEón carlos Departamento de Geografía Física Instituto de Geografía Universidad Nacional Autónoma de México. Circuito exterior s/n Ciudad Universitaria 04510 Mexico Distrito Federal Mexico Unidad Académica de Estudios Regionales de la Coordinación de Humanidades Universidad Nacional Autónoma de México

This investigation is an analysis of the influence of landform instability on the distribution of land-use dynamics in a hydrographical basin, located in the Mexican Volcanic Belt mountain range (central Mexico), currently affected by substantial changes in land use and deforestation. A landform map was produced, in addition to seven attribute maps - altimetry, drainage density, slope, relief energy, potential erosion, geology and tectonics - which were considered as factors for determining landform instability through Multi-criteria Evaluation Analysis. Likewise, the direction and rhythm of land-use dynamics were analyzed in four dates - between 1976 and 2000 - and cross tabulations were made between them, in order to analyze the trends and processes of land-use dynamics. Afterwards, the databases obtained were cross tabulated with the landform variables to derive areas, percentages and correlation indices. In the study area, high-instability landforms are associated with most ancient volcanic and sedimentary landforms, where high altitude, drainage density, slope and potential to develop gravitational and fluvial processes are the major factors favouring a land-use pattern, dominated by the conservation of extensive forest land, abandonment of human land use and regeneration of disturbed areas. In contrast, low-instability landforms correspond to alluvial plains and lava hills covered by pyroclasts, where low potential erosion to develop fluvial processes, added to water and soil availability and accessibility, have favoured a land-use pattern dominated by the expansion of agroforestry plantations and human settlements, showing a marked trend towards either intensification or permanence of the current land use and with little abandonment and regeneration.

关键词： Landform instability Multi-criteriaEvaluation Analysis Land-use change and processes Tuxpan River Basin