Search results for " Transformation"
showing 10 items of 1043 documents
Identification of Synaptic Integration Mode in CA3 Pyramidal Neuron Model
2019
International audience; A morphologically realistic and anisotropic model of CA3 pyramidal neuron was developed to determine the synaptic integration modes the neuron is able to perform. Linearity and nonlinearity were identified in different synaptic locations with varying active mechanisms such as the presence of ionic channels in the dendritic arbor and the types of receptors in the synapse. Quantification of synaptic integration was performed using paired-pulse stimulation protocol and subthreshold input/output (sI/O) transformation. Results show that the mode of synaptic integration is location-dependent while the linearity or nonlinearity in the integration is mainly influenced by the…
Rigidity of quasi-isometries for symmetric spaces and Euclidean buildings
1997
Abstract We study quasi-isometries between products of symmetric spaces and Euclidean buildings. The main results are that quasi-isometries preserve the product structure, and that in the irreducible higher rank case, quasi-isometries are at finite distance from homotheties.
Tecsis: Low-Cost Methodology To Distinguish Archaeological Findings
2006
The automatic or semi-automatic research of archaeological findings includes some methodologies and algorithms of the Computer Vision. Reconstruction of a scene is one of the key step to get the solution to that challenge. This paper will address a methodology to reconstruction underwater scenes with mosaicing techniques. The reconstruction of scene will be the video-mosaic of sea bottom landscapes starting from single video frames. The methodology is based on the evaluation of the optic °ow in between frames, and its motion estimation has been evaluated on the extracted features from the common areas of consecutive pairs frames. This approach carried out the motion model from a geometric p…
Elementary transformation analysis for Array-OL
2009
Array-OL is a high-level specification language dedicated to the definition of multidimentional intensive signal processing applications. It allows to specify both the task parallelism and the data parallelism of these applications on focusing on their complex multidimensional data access patterns. Several tools exist for implementing an Array-OL specification as a data parallel program. While Array-OL can be used directly, it is often convenient to be able to deduce part of the specification from a sequential version of the application. This paper proposes such an analysis and examines its feasibility and its limits.
Ciudadanía y transformación social: Nuevos discursos y acción contra el cambio climático
2021
El canvi climatic protagonitza el debat mediambiental des de fa tres decades. Malgrat els acords internacionals adoptats, la humanitat no ha aconseguit frenar l’augment de la temperatura planetaria. La crisi del coronavirus ha relegat el debat sobre l’emergencia climatica a un segon pla, encara que les connexions entre canvi climatic i pandemia demostren les multiples raons que tenim per a actuar pel clima. Les politiques publiques han afavorit regulacions, instruments de mercat i estrategies de modernitzacio ecologica que consoliden un capitalisme verd que agreuja el problema i el despolititza. La lluita contra el canvi climatic necessita un nou enfocament, basat en la politica ciutadana i…
Three-dimensional topological loops with nilpotent multiplication groups
2015
In this paper we describe the structure of indecomposable nilpotent Lie groups which are multiplication groups of three-dimensional simply connected topological loops. In contrast to the 2-dimensional loops there is no connected topological loop of dimension ≥ 3 such that the Lie algebra of its multiplication group is an elementary filiform Lie algebra. We determine the indecomposable nilpotent Lie groups of dimension ≤ 6 and their subgroups which are the multiplication groups and the inner mapping groups of the investigated loops. We prove that all multiplication groups have 1-dimensional centre and the corresponding loops are centrally nilpotent of class 2.
Multiplicity of ground states for the scalar curvature equation
2019
We study existence and multiplicity of radial ground states for the scalar curvature equation $$\begin{aligned} \Delta u+ K(|x|)\, u^{\frac{n+2}{n-2}}=0, \quad x\in {{\mathbb {R}}}^n, \quad n>2, \end{aligned}$$when the function $$K:{{\mathbb {R}}}^+\rightarrow {{\mathbb {R}}}^+$$ is bounded above and below by two positive constants, i.e. $$0 0$$, it is decreasing in (0, 1) and increasing in $$(1,+\infty )$$. Chen and Lin (Commun Partial Differ Equ 24:785–799, 1999) had shown the existence of a large number of bubble tower solutions if K is a sufficiently small perturbation of a positive constant. Our main purpose is to improve such a result by considering a non-perturbative situation: we ar…
Multiplicity of Radial Ground States for the Scalar Curvature Equation Without Reciprocal Symmetry
2022
AbstractWe study existence and multiplicity of positive ground states for the scalar curvature equation $$\begin{aligned} \varDelta u+ K(|x|)\, u^{\frac{n+2}{n-2}}=0, \quad x\in {{\mathbb {R}}}^n\,, \quad n>2, \end{aligned}$$ Δ u + K ( | x | ) u n + 2 n - 2 = 0 , x ∈ R n , n > 2 , when the function $$K:{{\mathbb {R}}}^+\rightarrow {{\mathbb {R}}}^+$$ K : R + → R + is bounded above and below by two positive constants, i.e. $$0<\underline{K} \le K(r) \le \overline{K}$$ 0 < K ̲ ≤ K ( r ) ≤ K ¯ for every $$r > 0$$ r > 0 , it is decreasing in $$(0,{{{\mathcal {R}}}})$$ ( 0 , R ) and increasing in $$({{{\mathcal {R}}}},+\infty )$$ ( R , + ∞ ) for a certain $${{{\mathcal {R}}}}&g…
Poisson convergence on continuous time branching random walks and multistage carcinogenesis.
1982
A theorem for Poisson convergence on realizations of two-dimensional Branching Random Walks with an underlying continuous time Markov Branching Process is proved. This result can be used to gain an approximation for the number of cells having sustained a certain deficiency after a long time in multistage carcinogenesis.
On Mardia’s Tests of Multinormality
2004
Classical multivariate analysis is based on the assumption that the data come from a multivariate normal distribution. The tests of multinormality have therefore received very much attention. Several tests for assessing multinormality, among them Mardia’s popular multivariate skewness and kurtosis statistics, are based on standardized third and fourth moments. In Mardia’s construction of the affine invariant test statistics, the data vectors are first standardized using the sample mean vector and the sample covariance matrix. In this paper we investigate whether, in the test construction, it is advantageous to replace the regular sample mean vector and sample covariance matrix by their affi…