Search results for "Mathematic"
showing 10 items of 24974 documents
Software/Hardware Issues in Modelling Insect Brain Architecture
2011
The concept of cognitive abilities is commonly associated to humans and animals like mammals, birds and others. Nevertheless, in the last years several research groups have intensified the studies on insects that posses a much simpler brain structure even if they are able to show interesting memory and learning capabilities. In this paper a survey on some key results obtained in a joint research activity among Engineers and Neurogeneticians is reported. They were focussed toward the design and implementation of a model of the insect brain inspired by the Drosophila melanogaster. Particular attention was paid to the main neural centers the Mushroom Bodies and the Central Complex. Moreover a …
Dynamin-Like Proteins Are Potentially Involved in Membrane Dynamics within Chloroplasts and Cyanobacteria
2017
Dynamin-like proteins (DLPs) are a family of membrane-active proteins with low sequence identity. The proteins operate in different organelles in eukaryotic cells, where they trigger vesicle formation, membrane fusion, or organelle division. As discussed here, representatives of this protein family have also been identified in chloroplasts and DLPs are very common in cyanobacteria. Since cyanobacteria and chloroplasts, an organelle of bacterial origin, have similar internal membrane systems, we suggest that DLPs are involved in membrane dynamics in cyanobacteria and chloroplasts. Here, we discuss the features and activities of DLPs with a focus on their potential presence and activity in ch…
Prerequisites for the successful group mentoring of first-year university students: a case study
2018
In this article we present a case study on a group mentoring practice proven successful in earlier studies in terms of student self-regulation and collaboration. The purpose of our study was to unc...
Evaluation of a lattice-Boltzmann method for mercury intrusion porosimetry simulations
2004
We have simulated intrusion of a non-wetting liquid into pores of varying shape and size. Simulations were based on the lattice-Boltzmann method and the Shan–Chen multiphase model. The liquid–solid contact angle for pores with circular cross-section was found to be equal to that for pores with square cross-section, and constant even for small pore sizes if the discretised shape of the circular cross-section was taken into account. For comparison, contact angle was also determined for a liquid column descending in a capillary tube, and the results were found to be consistent. Application of the method to mercury intrusion porosimetry is discussed.
Analytical model for the long- distance tracer-transport in plants
2011
International audience; Recent investigations of long-distance transport in plants using non-invasive tracer techniques such as C radiolabeling monitored by positron emission tomography (PET) combined with magnetic resonance imaging (MRI) revealed the need of dedicated methods to allow a quantitative data analysis and comparison of such experiments. A mechanistic compartmental tracer transport model is presented, defined by a linear system of partial differential equations (PDEs). This model simplifies the complexity of axial transport and lateral exchanges in the transport pathways of plants (e.g. the phloem) by simulating transport and reversible exchange within three compartments using j…
Quadrature domains for the Helmholtz equation with applications to non-scattering phenomena
2022
In this paper, we introduce quadrature domains for the Helmholtz equation. We show existence results for such domains and implement the so-called partial balayage procedure. We also give an application to inverse scattering problems, and show that there are non-scattering domains for the Helmholtz equation at any positive frequency that have inward cusps.
Herramientas matemáticas para la valoración de la ampliación de una infraestructura portuaria
2003
infraestructura portuaria ya consolidada, que conlleva unas inversiones a largo plazo. Para ello hay que recurrir a medios de an´alisis capaces de recoger, en la medida de lo posible, la incertidumbre sobre la futura evoluci´on de los tr´aficos de mercanc´?as, sobre el efecto de la competencia entre puertos, etc., y que los m´etodos tradicionales no aproximan en toda su dimensi´on. Existe, adem´as, un problema de decisi´on de pol´?tica ´optima de gesti´on del proyecto que depende de variables de decisi´on que modelizan las opciones presentes en el mismo. Las oportunidades de inversi´on han sido tratadas como una colecci´on de opciones americanas sobre activos reales. Nosotros hemos optado p…
The Subjective Social Value of Education Construct: CrossValidation between School and University Teachers
2016
La Educación posee un valor social evidente que puede presentarse mediante indicadores de evaluación socio-educativos. Si bien la relación entre contexto escolar y rendimiento es evidente en diversos países, esta relación va perdiendo consistencia en los últimos años; ya que aparecen sectores estudiantiles que superan las predicciones académicas esperadas. Para ello, se estudia el Valor Social Subjetivo de la Educación en función de dos grupos docentes –escuela y universidad–. La metodología es complementaria a través de comités de expertos/as y validación cruzada de constructo. Se realizan análisis sobre dos escalas –relevancia y susceptibilidad de cambio– y entre dos muestras diferenciada…
Determinanty jakości kształcenia (przygotowania) w zakresie metodyki edukacji matematycznej w opinii studentów edukacji wczesnoszkolnej
2018
Wobec niekwestionowanej roli nauczyciela w procesie nauczania oczywiste jest, że jakość edukacji zależy od jakości kadry nauczycielskiej. Zatem problem, jak przygotować kandydata do zawodu, aby potrafił on projektować swoją późniejszą działalność pedagogiczną wymaga ciągłej refleksji. Kluczowym problemem kształcenia studentów jest poziom i jakość dydaktyki akademickiej. Jakość dydaktyki, zarówno pod względem merytorycznym i metodycznym oraz relacje interpersonalne z wykładowcami mają bowiem wpływ na rozwój studenta oraz na poziom kompetencji, jakie uzyska on w trakcie realizowanych studiów. W tekście dokonano próby ustalenia, jakie czynniki, zdaniem studentów edukacji wczesnoszkolnej, mają …
On one-dimensionality of metric measure spaces
2019
In this paper, we prove that a metric measure space which has at least one open set isometric to an interval, and for which the (possibly non-unique) optimal transport map exists from any absolutely continuous measure to an arbitrary measure, is a one-dimensional manifold (possibly with boundary). As an immediate corollary we obtain that if a metric measure space is a very strict $CD(K,N)$ -space or an essentially non-branching $MCP(K,N)$-space with some open set isometric to an interval, then it is a one-dimensional manifold. We also obtain the same conclusion for a metric measure space which has a point in which the Gromov-Hausdorff tangent is unique and isometric to the real line, and fo…