Noticias en español
Seminars appear in decreasing order in relation to date. To find an activity of your interest just go down on the list. Normally seminars are given in English. If not, they will be marked as Spanish Only.
Optimal methods for combining discrete p-values.
Abstract: Combining the significance of multiple experiments regarding the same scientific hypothesis is a crucial method for global hypothesis testing, with applications in meta-analysis, signal detection, and other data-integrative studies. Such procedures consider a group of p-values, $P_1, \cdots, P_n$, to form a summary statistic to determine the overall evidence against a global null hypothesis. Mathematical studies often assume that the underlying statistics are continuous and independent, due to their homogeneous and straightforward...
Minimum expansion factors of orientation-reversing pseudo-Anosov maps.
RESUMEN: Pseudo-Anosov maps are prevalent among mapping classes of surfaces. Given a pA map, the expansion factor measures the complexity of its dynamics. It is a classical result that the set of expansion factors (viewed as a subset of the set of real numbers) among all pA maps defined on a fixed surface has a minimum element. This minimum expansion factor can be thought of as the systole of the moduli space for the Teichmüller metric. Its value is not known for the genus larger than three.
Desarrollo de un colector de concentración solar Fresnel para calor de procesos en Ecuador.
Abstract:El grupo de investigación SCINERGY de la Escuela Politécnica Nacional ha emprendido en la investigación y desarrollo de un colector solar de concentración tipo Fresnel para producción de calor de procesos (< 180ºC), que pueda ser construido con las capacidades tecnológicas locales. Este trabajo muestra los avances y los retos alrededor de este objetivo. El desarrollo local de esta tecnología apoyaría en la diversificación de la matriz energética introduciendo fuentes renovables.
Generalized Quasi-Geostrophy for Moist Spatially Anisotropic Atmospheric Flows with Phase Changes.
Summary: Traditionally, the simulation of precipitating convection use a non-Boussinesq dynamical core such as the anelastic equations, and would incorporate water substance in all of its phases: vapour (cloud and rain), liquid and ice. Furthermore, the liquid water phase would be separated into cloud water (small droplets suspended in air) and rain water (larger droplets that fall). Depending on environmental conditions, the moist convection may organize itself on multiple length and time scales. One of the minimal representations of water...
The Limitations of Machine Learning & Us.
Abstract: Machine learning (ML), particularly deep learning, is being used everywhere. However, not always is used well, ethically and scientifically. In this talk we first do a deep dive in the limitations of supervised ML and data, its key component. We cover small data, datification, bias, predictive optimization issues, evaluating success instead of harm, and pseudoscience, among other problems. The second part is about our own limitations using ML, including different types of human incompetence: cognitive biases, unethical...
A variational and numerical approach to model inverse problems applied in subduction earthquakes.
Abstract: This talk presents a mixed variational formulation for the problem of the elasticity equation with jump conditions in an interface with the purpose of modeling subduction earthquakes by introducing the concept of coseismic jump. For this new problem, we introduced an optimal control problem that seeks to recover the coseismic jump from boundary observations. Both problems can be discretized by applying mixed finite elements. Synthetic results applied to a realistic context will be presented. Finally, we analyze some improvements for...
