A Survey on Spherical Spline Approximation

Spline functions that approximate data given on the sphere are developed in a weighted Sobolev space setting. The flexibility of the weights makes possible the choice of the approximating function in a way which emphasizes attributes desirable for the particular application area. Examples show that certain choices of the weight sequences yield known methods. A convergence theorem containing explicit constants yields a usable error bound. Our survey ends with the discussion of spherical splines in geodetically relevant pseudodifferential equations

Filosofía política e ideología: ¿Una relación difícil o complementaria?

This paper examines the relationship between the fields of moral and political philosophy and the study of ideology. It begins by addressing a number of reservations philosophers usually have regarding the scholarly status of ideology research. It then proceeds to highlight the distinct style of philosophical inquiry, namely, its seamless continuity between the study of philosophy and the arguments it examines, which contrasts with the professional language of the study of ideologies, clearly distinguished from that of ideologues. The paper then presents a conceptual perspective for the study of ideologies that complements the contributions from moral and political philosophy. Arguably, moral and political philosophy and ideology studies can fruitfully share methods and insights.Este trabajo examina la relación entre los campos de la filosofía moral y política y el estudio de las ideologías. Comienza por abordar una serie de reservas que los filósofos tienen usualmente sobre el estatuto científico de la investigación sobre ideologías. Procede a continuación a destacar el estilo singular de la investigación filosófica: su continuidad sin ruptura entre el estudio de la filosofía y los argumentos que examina, que contrasta con el lenguaje profesional del estudio de las ideologías, claramente diferenciado del lenguaje de los ideólogos. El trabajo presenta a continuación una perspectiva conceptual para el estudio de las ideologías, que complementa las contribuciones de la filosofía moral y política. Finalmente defiende que la filosofía moral y política y los estudios sobre ideologías pueden compartir de un modo fructífero métodos y visiones

Revisiting Contextualism in Political Theory: Putting Principles into Context

© 2017, Springer Nature B.V. In this article, we articulate and defend a contextual approach to political theory. According to what we shall call ‘iterative contextualism’, context has two important roles to play in determining what is required by justice. First, it is through the exploration and evaluation of multiple contexts that general principles are devised, revised and refined. Second, significant weight should be given to the norms to be found in specific contexts because the people affected by those norms strongly identify with them. Having said this, the application of general principles to particular contexts may still result in recommendations which deviate to some degree from the prevailing norms. In this case, we shall argue thatalthough justice requires something other than what local norms say, what is required is likely to be intimated by the relevant context. Thus, whilst considerations of identification act as significant constraints on iterative contextualists’ thinking, the idea of intimations provides them with an important resource

T cell metabolism drives immunity

Lymphocytes must adapt to a wide array of environmental stressors as part of their normal development, during which they undergo a dramatic metabolic remodeling process. Research in this area has yielded surprising findings on the roles of diverse metabolic pathways and metabolites, which have been found to regulate lymphocyte signaling and influence differentiation, function and fate. In this review, we integrate the latest findings in the field to provide an up-to-date resource on lymphocyte metabolism

Orthogonal and non-orthogonal multiresolution analysis, scale discrete and exact fully discrete wavelet transform on the sphere

Based on a new definition of delation a scale discrete version of spherical multiresolution is described, starting from a scale discrete wavelet transform on the sphere. Depending on the type of application, different families of wavelets are chosen. In particular, spherical Shannon wavelets are constructed that form an orthogonal multiresolution analysis. Finally fully discrete wavelet approximation is discussed in case of band-limited wavelets

Multiresolution Analysis by Spherical Up Functions

A new class of locally supported radial basis functions on the (unit) sphere is introduced by forming an infinite number of convolutions of ''isotropic finite elements''. The resulting up functions show useful properties: They are locally supported and are infinitely often differentiable. The main properties of these kernels are studied in detail. In particular, the development of a multiresolution analysis within the reference space of square--integrable functions over the sphere is given. Altogether, the paper presents a mathematically significant and numerically efficient introduction to multiscale approximation by locally supported radial basis functions on the sphere

Biorthogonal Locally Supported Wavelets on the Sphere Based on Zonal Kernel Functions

This paper presents a method for approximating spherical functions from discrete data of a block-wise grid structure. The essential ingredients of the approach are scaling and wavelet functions within a biorthogonalisation process generated by locally supported zonal kernel functions. In consequence, geophysically and geodetically relevant problems involving rotation-invariant pseudodifferential operators become attackable. A multiresolution analysis is formulated enabling a fast wavelet transform similar to the algorithms known from one-dimensional Euclidean theory

A: New Wavelet Methods for Approximating Harmonic Functions; B: Satellite Gradiometry - from Mathematical and Numerical Point of View

Some new approximation methods are described for harmonic functions corresponding to boundary values on the (unit) sphere. Starting from the usual Fourier (orthogonal) series approach, we propose here nonorthogonal expansions, i.e. series expansions in terms of overcomplete systems consisting of localizing functions. In detail, we are concerned with the so-called Gabor, Toeplitz, and wavelet expansions. Essential tools are modulations, rotations, and dilations of a mother wavelet. The Abel-Poisson kernel turns out to be the appropriate mother wavelet in approximation of harmonic functions from potential values on a spherical boundary