Dpto. Matemática Aplicada51https://uvadoc.uva.es/handle/10324/11762024-08-06T23:52:46Z2024-08-06T23:52:46ZGrupo de Innovación Docente MEIITOR y PID-23-24-067: Anexo4Fernando Velázquez, Marisahttps://uvadoc.uva.es/handle/10324/687522024-07-15T19:00:55Z2024-01-01T00:00:00ZTabla completa con el grado de cumplimiento de los objetivos propuestos.
2024-01-01T00:00:00ZGrupo de Innovación Docente MEIITOR y PID-23-24-067: Anexo3Fernando Velázquez, Marisahttps://uvadoc.uva.es/handle/10324/687502024-07-15T19:00:55Z2024-01-01T00:00:00ZImágenes del PID2324_67
2024-01-01T00:00:00ZGrupo de Innovación Docente MEIITOR y PID_23_24_067: Anexo2Fernando Velázquez, Marisahttps://uvadoc.uva.es/handle/10324/687492024-07-15T19:00:54Z2024-01-01T00:00:00ZDocumento de evaluación: actas reuniones PID2324_67, encuestas realizadas a tutores, mentores y tutelados: modelo, resultados y análisis, metavaluación, DAFO y propuestas de mejora.
2024-01-01T00:00:00ZGrupo de Innovación Docente MEIITOR y PID-23-24-067: Anexo1Fernando Velázquez, Marisahttps://uvadoc.uva.es/handle/10324/687482024-07-15T19:00:53Z2023-01-01T00:00:00ZInformación completa de los cursos formación para mentores incluyendo gamificación y documentos renovados para implementar el PAT_Mentor en 24-25 (agenda, guía, consejos).
2023-01-01T00:00:00ZOn the precursor environments to mountain lee wave clouds in central Iberia under CMIP6 projectionsDíaz Fernández, JavierCalvo Sancho, CarlosBolgiani, PedroGonzález Alemán, Juan JesúsFarrán Martín, José IgnacioSastre Marugán, MarianoMartín Pérez, María Luisahttps://uvadoc.uva.es/handle/10324/673322024-05-03T19:01:28Z2024-01-01T00:00:00ZMountain lee waves present significant hazards to aviation, often inducing turbulence and aircraft icing. The current study focuses on understanding the potential impact of global climate change on the precursor environments to mountain lee wave cloud episodes over central Iberia. We examine the suitability of several Global Climate Models (GCMs) from CMIP6 in predicting these environments using the ERA5 reanalysis as a benchmark for performance. The dataset is divided into two periods: historical data (2001–2014) and projections for the SSP5–8.5 future climate scenario (2015–2100). The variations and trends in precursor environments between historical data and future climate scenarios are exposed, with a particular focus on the expansion of the Azores High towards the Iberian Peninsula, resulting in increased zonal winds throughout the Iberian Peninsula in the future. However, the increase in zonal wind is insufficient to modify the wind pattern, so future mountain lee wave cloud events will not vary significantly. The relative humidity trends reveal no significant changes. Moreover, the risk of icing precursor environments connected with mountain lee wave clouds is expected to decrease in the future, due to rising temperatures. Our results highlight that the EC-EARTH3 GCM reveals the closest alignment with ERA5 data, and statistically significant differences between the historical and future climate scenario periods are presented, making EC-EARTH3 a robust candidate for conducting future studies on the precursor environments to mountain lee wave cloud events.
2024-01-01T00:00:00ZIntraseasonal‐to‐Interannual Analysis of Discharge and Suspended Sediment Concentration Time‐Series of the Upper Changjiang (Yangtze River)Juez, C.Garijo, N.Hassan, M. A.Nadal‐Romero, E.https://uvadoc.uva.es/handle/10324/660032024-02-08T20:02:04Z2021-01-01T00:00:00Z-
2021-01-01T00:00:00ZSediment loss modelling framework for the Bradano river basin, southern Italy, 1950–2020Diodato, NazzarenoBorrelli, PasqualeGómara Cardalliaguet, IñigoBellocchi, Giannihttps://uvadoc.uva.es/handle/10324/659822024-02-08T20:02:03Z2023-01-01T00:00:00ZHazardous hydrological events cause soil erosion and it is essential to anticipate the potential environmental impacts of prevail-
ing erosion processes that occur at different time-scales. Here, we present the modelling of net soil erosion rates for the Bradano
River Basin (southern Italy), based on rainfall erosivity, surface overland flow and transport sub-models. A semi-empirical
framework was developed, upscaling point rainfall values based on the Foster-Thornes approach in order to give an insight into
monthly and annual soil losses over the period 1950–1958 and 1961 (calibration) and over a longer time-frame (1950–2020:
reconstruction). In the 2765-km2 study area, ~ 68% of the sediment mobilized within the basin reached the basin outlet (mean
value for 1950–2020: ~ 366 Mg km−2 yr−1
). A moderate declining trend in net erosion rates was observed after the 1980s, con-
current with the contraction of cropland in favour of natural vegetation and river channelization. Our results suggest that the
parsimonious principle used here seems sufficiently robust to be suitable for applications in other Mediterranean landscapes.
2023-01-01T00:00:00ZGeneralized pitchfork bifurcations in D-Concave nonautonomous scalar ordinary differential equationsDueñas Pamplona, JesúsNúñez Jiménez, María del CarmenObaya, Rafaelhttps://uvadoc.uva.es/handle/10324/659812024-02-08T20:02:02Z2023-01-01T00:00:00ZThe global bifurcation diagrams for two different one-parametric perturbations (+λx and
+λx2 ) of a dissipative scalar nonautonomous ordinary differential equation x′ = f (t, x)
are described assuming that 0 is a constant solution, that f is recurrent in t, and that its
first derivative with respect to x is a strictly concave function. The use of the skewproduct
formalism allows us to identify bifurcations with changes in the number of minimal sets and
in the shape of the global attractor. In the case of perturbation +λx, a so-called generalized
pitchfork bifurcation may arise, with the particularity of lack of an analogue in autonomous
dynamics. This new bifurcation pattern is extensively investigated in this work
2023-01-01T00:00:00ZOptimal policy for an inventory system with demand dependent on price, time and frequency of advertisementSan José Nieto, Luis AugustoSicilia Rodríguez, JoaquínAbdul Jalbar, Beatrizhttps://uvadoc.uva.es/handle/10324/658892024-04-01T20:00:39Z2021-01-01T00:00:00ZThis paper studies a new lot-size inventory problem for products whose demand pattern is dependent on price, advertising frequency and time. It is considered that the demand rate of an item multiplicatively combines the effects of a power function dependent on the frequency of advertisement and a function dependent on both selling price and time. This last function is additively separable in two power functions, one varies with the selling price and the other depends on the time since the last inventory replenishment. Moreover, it is assumed that the holding cost per unit of item is a non-linear function of time in stock. Shortages are not allowed. The aim consists of determining the frequency of advertisement, the selling price and the length of the stock period to maximize the average profit per unit time. This leads to a mixed integer non-linear inventory problem, which is solved by using an efficient algorithm previously developed. The inventory model considered here extends several inventory models previously proposed in the literature. Some numerical examples are solved to illustrate how the algorithm works to obtain optimal inventory policies. Finally, a sensitivity analysis for the optimal solution with respect to the parameters of the inventory system is presented.
2021-01-01T00:00:00ZAn inventory system with demand dependent on both time and price assuming backlogged shortagesSan José Nieto, Luis AugustoSicilia Rodríguez, JoaquínAlcaide López de Pablo, Davidhttps://uvadoc.uva.es/handle/10324/658862024-02-07T20:02:01Z2018-01-01T00:00:00ZIn this work we analyze an inventory model for items whose demand is a bivariate function of price and time. It is supposed that the demand rate multiplicatively combines the effects of a time-power function and a price-logit function. The aim is to maximize the profit per time unit, assuming that the inventory cost per time unit is the sum of the holding, shortage, ordering and purchasing costs. An algorithm is developed to find the optimal price, the optimal lot size and the optimal replenishment cycle. Several numerical examples are introduced to illustrate the solution procedure.
2018-01-01T00:00:00ZHow to avoid order reduction when Lawson methods integrate nonlinear initial boundary value problemsCano Urdiales, Begoñahttps://uvadoc.uva.es/handle/10324/656182024-02-05T20:03:40Z2022-01-01T00:00:00ZIt is well known that Lawson methods suffer from a severe order reduction when
integrating initial boundary value problems where the solutions are not periodic in
space or do not satisfy enough conditions of annihilation on the boundary. However,
in a previous paper, a modification of Lawson quadrature rules has been suggested
so that no order reduction turns up when integrating linear problems subject to timedependent
boundary conditions. In this paper, we describe and thoroughly analyse a
technique to avoid also order reduction when integrating nonlinear problems. This is
very useful because, given any Runge–Kutta method of any classical order, a Lawson
method can be constructed associated to it for which the order is conserved.
2022-01-01T00:00:00ZWhy Improving the Accuracy of Exponential Integrators Can Decrease Their Computational Cost?Cano Urdiales, Begoñahttps://uvadoc.uva.es/handle/10324/656172024-02-05T20:03:39Z2021-01-01T00:00:00ZIn previous papers, a technique has been suggested to avoid order reduction when inte-
grating initial boundary value problems with several kinds of exponential methods. The technique
implies in principle to calculate additional terms at each step from those already necessary without
avoiding order reduction. The aim of the present paper is to explain the surprising result that,
many times, in spite of having to calculate more terms at each step, the computational cost of doing
it through Krylov methods decreases instead of increases. This is very interesting since, in that way,
the methods improve not only in terms of accuracy, but also in terms of computational cost.
2021-01-01T00:00:00ZCMMSE: Analysis of order reduction when Lawson methods integrate nonlinear initial boundary value problemsCano Urdiales, Begoñahttps://uvadoc.uva.es/handle/10324/656162024-02-05T20:03:38Z2022-01-01T00:00:00ZIn this paper a thorough analysis is carried out of the type of order reductionthat Lawson methods exhibit when used to integrate nonlinear initial boundaryvalue problems. In particular, we focus on nonlinear reaction-diffusion prob-lems, and therefore, this study is important in a large number of practicalapplications modeled by this type of nonlinear equations. A theoretical study ofthe local and global error of the total discretization of the problem is carried out,taking into account both, the error coming from the space discretization andthat due to the integration in time. These results are also corroborated by thenumerical experiments performed in this paper.
2022-01-01T00:00:00ZA pseudospectral method for Option Pricing with Transaction Costs under Exponential UtilityFrutos Baraja, Francisco Javier deGatón, Víctorhttps://uvadoc.uva.es/handle/10324/654682024-01-31T20:01:31Z2021-10-01T00:00:00ZThis paper concerns the design of a Fourier based pseudospectral numerical method for the model of European option pricing with transaction costs under exponential utility derived by Davis, Panas and Zariphopoulou in Davis et al. (1993). Computing the option price involves solving two stochastic optimal control problems. With an exponential utility function, the dimension of the problem can be reduced, but one has to deal with high absolute values in the objective function. We propose two changes of variables that reduce the impact of the exponential growth and a Fourier pseudospectral method to solve the resulting non linear equation. Numerical analysis of the stability, consistency, convergence and localization error of the method are included. Numerical experiments support the theoretical results and the effect of incorporating transaction costs is also studied.
2021-10-01T00:00:00ZSquare matrices with the inverse diagonal propertyFurtado, SusanaJohnson, Charles R.Marijuán, CarlosPisonero, Miriamhttps://uvadoc.uva.es/handle/10324/654052024-01-31T20:01:30Z2023-01-01T00:00:00ZWe identify the class of real square invertible matrices A for which the signs of the diagonal entries of A 1 match those of A, and begin their study. We say such matrices have the inverse diagonal property (IDP). This class includes many important classes: the positive definite matrices, the M-matrices, the totally positive matrices and some variants, the P-matrices, the diagonally dominant and H-matrices and their inverse classes, as well as triangular matrices. This class is closed under any real invertible diagonal multiplication on either the right or the left. So questions about this class can be reduced to the case of positive diagonal entries. Other basic properties are given. One theme is what conditions need be added to the IDP to insure membership in a familiar class. For example, the positive definite matrices are characterized as certain IDP matrices with special conditions on certain particular principal minors. The tridiagonal case is highlighted. Certain specially simple conditions on such matrices are mentioned that ensure them to be P-matrices, positive definite matrices or M-matrices. We also note that recent results about the invertibility of weakly diagonally dominant matrices are used. Examples are given throughout the paper.
2023-01-01T00:00:00ZDiagonal dominance and invertibility of matricesJohnson, Charles R.Marijuán, CarlosPisonero, Miriamhttps://uvadoc.uva.es/handle/10324/654042024-01-31T20:01:30Z2023-01-01T00:00:00ZA weakly diagonally dominant matrix may or may not be invertible. We characterize, in terms of combinatorial structure and sign pattern when such a matrix is invertible, which is the common case. Examples are given.
2023-01-01T00:00:00Z