A model to analyze soccer offensive phase

Orientador: Sergio Augusto CunhaDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação FísicaResumo: A análise de jogos de futebol apresenta uma vasta gama de possibilidades que podem estar relacionadas ao desempenho dos atletas e ao resultado do jogo. Em relação a aplicações de análises matemáticas no futebol, a principal forma para analisar a velocidade do ataque na literatura foi apresentada por Yue et al. (2008). O objetivo deste trabalho foi propor um modelo de análise da velocidade de progressão da bola ao gol no futebol e apresentar os resultados de dez jogos da elite do futebol brasileiro. Os jogos foram filmados com quatro a seis câmeras digitais (7,5 a 30 Hz) e as coordenadas bidimensionais dos jogadores durante a partida foram obtidas pelo software Dvideo (Figueroa, Leite e Barros, 2006a; b). As ações técnicas também foram registradas pelo software Dvideo, conforme Moura (2006). Foram levadas em consideração na análise todas as sequências ofensivas do jogo com pelo menos quatro ações técnicas. Em cada sequência ofensiva, para cada par de ações sequenciais (ai e ai+1), os vetores VPG foram calculados obedecendo a seguinte equação: VPG = (vm ? gu)gu onde gu é o vetor unitário de g, definido pelo ponto médio entre as duas ações ai e ai+1 (ponto M) e o ponto médio do gol (G); vm tem direção e sentido definidos pela diferença da posição das ações ai e ai+1, origem no ponto M e módulo igual à velocidade média da bola. Nos casos em que ||VPG|| for diferente de zero, houve progressão ou afastamento da bola em relação ao gol. Sempre que a distância euclidiana entre a ação ai+1 e o gol for menor do que a distância euclidiana entre a ação ai e o gol, isso representará progressão da bola ao gol. Caso contrário, terá ocorrido afastamento. Foram considerados na análise apenas os casos de progressão ao gol. Os resultados para 10 jogos foram apresentados por média e desvio padrão dos valores de ||VPG||. As equipes 5, 13, 17 e 19 obtiveram valores de ||VPG|| significativamente maiores na faixa 1 (próxima ao gol) em comparação com a faixa 2 (longe do gol) da mesma equipe. Equipes que venceram obtiveram valores de ||VPG|| significativamente maiores na faixa 2 do que equipes que perderam. Além disso, os vetores VPG foram apresentados graficamente para 17 gols analisados e para todas as sequências ofensivas terminadas em finalização de cada equipe. Concluiu-se que, além de ter sido possível caracterizar o ataque das equipes com base na velocidade de progressão da bola ao gol, a análise das sequências ofensivas no futebol por meio do modelo proposto apresentou particularidades das sequências ofensivas das equipes que não foram encontrados em outros estudos na literatura e que podem auxiliar na análise de desempenho no futebolAbstract: Studies related to game analysis in soccer have shown many different variables that might be related to the athlete's performance and match result. Along the mathematical approaches of the soccer game, the main form to analyze the attack speed was presented by Yue et al. (2008). The aim of the present study was to elaborate a model to analyze the ball speed towards the goal in soccer and to show the results from 10 soccer games of Brazilian elite teams. The games were recorded with four to six cameras (7.5 to 30 Hz) and de bidimensional coordinates were obtained using the Dvideo software (Figueroa, Leite e Barros, 2006a; b). Technical actions were also registered using the Dvideo software, as shown in Moura (2006). All offensive sequences with at least four technical actions were considered in the analysis. In each offensive sequence, for every pair of sequential technical actions (ai and ai+1), the vectors VPG were calculated following this equation: VPG = (vm ? gu)gu where gu is the unit vector of g, defined by the middle point between the actions ai and ai+1 (point M) and the middle point of the target goal (G); vm has direction defined by the difference of the position of the actions ai and ai+1, magnitude as the average speed of the ball and origin in the point M. When ||VPG|| ? 0 , it means that there were progression or regression in relation to the goal. When the Euclidian distance between the action ai+1 and the goal is minor than the Euclidian distance between the action ai and the target, goal progression will have happened. Otherwise, the action will have moved the ball away from the goal. Only the cases that progression to the goal occurred were considered in the analysis. The results of ten games were presented by mean and standard deviation of ||VPG||. Teams 5, 13, 17 and 19 showed values of ||VPG|| significantly higher near the goal then far away from the goal, when comparing different sectors of the same team. Teams that won the game showed higher values of ||VPG|| far from the goal than teams that lost the games, when comparing the same sector. Also, VPG vectors were presented graphically for 17 goals and all offensive sequences ended in shots for every team. It was possible to characterize the offensive phase of the teams based on the ball speed towards the goal. In conclusion, the model proposed showed many aspects of the offensive sequences of each team that have not been presented by other studies in the literature and can be useful to analyze match performance in soccerMestradoBiodinamica do Movimento e EsporteMestre em Educação Físic

Preparation of ribsomal subunits by gel filtration

A Oiss{!y'tation uhm'itted in fulfilment of the r~;~airements, for' the degree of f·1aster· oi~'j Science at the University of the ~titwatersrand ' Juhanoasbul"g January 1991An attempt was made to separate ribosomal subunits by gel filtl'ation on Trisacryl GF2000 and Sepharose 4B. Trisacryl GP~2000,a sYllthet'ic gol, , separated rat .ljver rlbosonal subunits orl 'f~'135,em column with a resolution of ""Or3, resulting 'in <'1" 60 rJ impm''ity 'of each of the \~ subunits. subunits" were not resolved. Sepharose 4131 an agarose based gol, separated " the subunits by adsorpttcn chromatography rathr.r than 'i>.V () Q ':) At 4°C, the 405 .subunf ts were eluted with a kd () ruO,:~9( but the GOrf' ubud"its adsorbed to th~.'g,~Jl and were eluted I; /) when the temperature of "the column was increas~d to 250C..3SoC. (' ,. ('-. This edsorpt ion phenonenon seems to b{~ tl propert~ of a 11 agllrose -: \') ~\:; based gels studied here, includ'ing Sepharose 2.B and .seph'ato~eoBt arid is exc 1us iva to !,mamm'i'lan r ibosOIntrt subuni ts • Anal,ys1S 0'(" the , u subunits by in vitro r14C]polypheny1alanine sy'nthes'is showed OCI " ,,'c. /\ I 7', " diff'erence 'in the act lvtt ies of dbosoma'J ~ubunH~ p~epdrf#d by ;/'/ ' grndient centrifugation or by 5epharos,e cni"OmatogNPPY;' Analy~ii ~~of " (~ (( the subunits by ~crylamidec'ugarose coU)po5it~) gs1s resulted ,in the '/ resolution ,.:n"f subunits isolated fr'oill lower organisms in o II non-denaturlnq !Jcl systems and SI,lbut1its from m«mm~nan'tissue in II /'\';1 Ga'! f'iltrat'ion does tyffer a 5t!i:l;~'ble metrKld'¥or the pr~p;n~¥tiol1of <::) . I \) \\ I) ribosoma 1 'subunits I but only' if 'the act~orption JH'OrJ&~"t'Jo,s of ,) (,) ':' o ,1) ,

Two-dimensional Radiative Magnetohydrodynamic Simulations of Partial Ionization in the Chromosphere. II. Dynamics and Energetics of the Low Solar Atmosphere

We investigate the effects of interactions between ions and neutrals on the chromosphere and overlying corona using 2.5D radiative MHD simulations with the Bifrost code. We have extended the code capabilities implementing ion-neutral interaction effects using the Generalized Ohm's Law, i.e., we include the Hall term and the ambipolar diffusion (Pedersen dissipation) in the induction equation. Our models span from the upper convection zone to the corona, with the photosphere, chromosphere and transition region partially ionized. Our simulations reveal that the interactions between ionized particles and neutral particles have important consequences for the magneto-thermodynamics of these modeled layers: 1) ambipolar diffusion increases the temperature in the chromosphere; 2) sporadically the horizontal magnetic field in the photosphere is diffused into the chromosphere due to the large ambipolar diffusion; 3) ambipolar diffusion concentrates electrical currents leading to more violent jets and reconnection processes, resulting in 3a) the formation of longer and faster spicules, 3b) heating of plasma during the spicule evolution, and 3c) decoupling of the plasma and magnetic field in spicules. Our results indicate that ambipolar diffusion is a critical ingredient for understanding the magneto-thermo-dynamic properties in the chromosphere and transition region. The numerical simulations have been made publicly available, similar to previous Bifrost simulations. This will allow the community to study realistic numerical simulations with a wider range of magnetic field configurations and physics modules than previously possible.Comment: 13 figures. Accepted to be published in Ap

Characterizing, modelling and understanding the climate variability of the deep water formation in the North-Western Mediterranean Sea

Observing, modelling and understanding the climate-scale variability of the deep water formation (DWF) in the North-Western Mediterranean Sea remains today very challenging. In this study, we first characterize the interannual variability of this phenomenon by a thorough reanalysis of observations in order to establish reference time series. These quantitative indicators include 31 observed years for the yearly maximum mixed layer depth over the period 1980–2013 and a detailed multi-indicator description of the period 2007–2013. Then a 1980–2013 hindcast simulation is performed with a fully-coupled regional climate system model including the high-resolution representation of the regional atmosphere, ocean, land-surface and rivers. The simulation reproduces quantitatively well the mean behaviour and the large interannual variability of the DWF phenomenon. The model shows convection deeper than 1000 m in 2/3 of the modelled winters, a mean DWF rate equal to 0.35 Sv with maximum values of 1.7 (resp. 1.6) Sv in 2013 (resp. 2005). Using the model results, the winter-integrated buoyancy loss over the Gulf of Lions is identified as the primary driving factor of the DWF interannual variability and explains, alone, around 50 % of its variance. It is itself explained by the occurrence of few stormy days during winter. At daily scale, the Atlantic ridge weather regime is identified as favourable to strong buoyancy losses and therefore DWF, whereas the positive phase of the North Atlantic oscillation is unfavourable. The driving role of the vertical stratification in autumn, a measure of the water column inhibition to mixing, has also been analyzed. Combining both driving factors allows to explain more than 70 % of the interannual variance of the phenomenon and in particular the occurrence of the five strongest convective years of the model (1981, 1999, 2005, 2009, 2013). The model simulates qualitatively well the trends in the deep waters (warming, saltening, increase in the dense water volume, increase in the bottom water density) despite an underestimation of the salinity and density trends. These deep trends come from a heat and salt accumulation during the 1980s and the 1990s in the surface and intermediate layers of the Gulf of Lions before being transferred stepwise towards the deep layers when very convective years occur in 1999 and later. The salinity increase in the near Atlantic Ocean surface layers seems to be the external forcing that finally leads to these deep trends. In the future, our results may allow to better understand the behaviour of the DWF phenomenon in Mediterranean Sea simulations in hindcast, forecast, reanalysis or future climate change scenario modes. The robustness of the obtained results must be however confirmed in multi-model studies