Search results for "Model theory"

Mappings ofBMO-distortion and beltrami-type operators

2002

EFFECTIVE FINITE-DIFFERENCE METHODS FOR THE SOLUTIONS OF FILTRATION PROBLEMS IN MULTILAYER DOMAINS

1997

In papers [1,2] there were consider different assumptions for averaging methods along the vertical coordinate.These methods were applied for the mathematical simulation of the mass transfer process in multilayered underground systems. A specific feature of these problems is that it is necessity to solve the 3‐D initial‐boundary‐value problems for parabolic type partial differential equations of second order with piece‐wise parameters in multilayer domain.Therefore here an effective finite‐difference method for solving a problem of the above type is developed.This method may be considered as a generalization of the method of finite volumes [3] for the layered systems. In the case of constant…

Superharmonic functions are locally renormalized solutions

2011

Abstract We show that different notions of solutions to measure data problems involving p-Laplace type operators and nonnegative source measures are locally essentially equivalent. As an application we characterize singular solutions of multidimensional Riccati type partial differential equations.

Computer simulation of oxygen tension histograms--a possibility for interpretation of microelectrode measurements.

1972

Mit Sauerstoff-Mikroelektroden werden die lokalen Werte des Sauerstoffpartialdruckes im Mikrobereich der Organe gemessen und graphisch als Haufigkeitsverteilungen (Histogramme) dargestellt. Theoretisch wird der Einfluss der Kapillaranordnung (Gleich-, Gegenstromsystem und Kapillarnetzwerk) auf die Haufigkeitsverteilung der P02 Werte untersucht. Die fur zweidimensionale Modelle durchgefuhrte Analyse zeigt, dass Unterschiede in der Durchblutung, wie sie in den einzelnen Zweigen der Kapillarnetzwerke auftreten, einen starken Einfluss auf die Histogramme haben.

Lattice dynamics of zircon-type NdVO4 and scheelite-type PrVO4 under high-pressure

2021

Abstract Zircon-type NdVO4 and scheelite-type PrVO4 have been studied by means of Raman spectroscopy up to approximately 20 GPa. In the first compound, zircon-scheelite and scheelite-fergusonite phase transitions are reported at 6.4(3) and 19.6(4) GPa, respectively. In the case of scheelite-type PrVO4, a reversible phase transition to a PbWO4-III structure is observed at 16.8(5) GPa. In both cases, a scheelite-type structure is recovered in a metastable state at low pressures. The pressure evolution of the Raman modes is also reported. Our experimental findings are supported by ab initio calculations, which allowed us to discuss the role of mechanic and dynamical instabilities in the phase …

Sur les Codes ZigZag et Leur Décidabilité

1990

AbstractThis paper deals with zigzag factorizations and zigzag codes. The language of “zigzag” over a regular language is represented by constructing a special family of two-way automata. Decidability of zigzag codes, previously shown for the finite languages, is proved here for all regular languages by the analysis of the set of “crossing sequences” produced by a two-way automation in the family. We also obtain that it is decidable whether or not a two-way automation of a certain type is non-ambiguous.RésuméDans ce papier on reprend les notions de factorisation zigzag et de code zigzag. On construit pour tout langage rationnel, une famille d'automates bilatéres lesquels reconnaissent les m…

Argumentation in Mathematics

2013

In The Uses of Argument, Stephen Toulmin (1958) introduced a model of argumentation, in which what may be called the ‘layout of arguments’ is represented. This model has become a classic in argumentation theory and has been used in the analysis, evaluation and construction of arguments. Toulmin’s main thesis is that, in principle, one can make a claim of rationality for any type of argument, and that the criterion of validity depends on the nature of the problem in question. He rejects the idea of universal norms for evaluation of argumentation and that formal logic provides these norms. There is an essential difference between the norms which are relevant to the evaluation of everyday argu…

J. S. Beck’s Theory of theOriginal Representingas an Interpretation of Kant

2021

AbstractThis paper explores Beck’s theory oforiginal representingin order to discuss both its historical and theoretical relevance and its implications concerning Kant’s views on the capacity to judge. My first concern will be to highlight the main points of Beck’s Kant interpretation and to show at which points he misunderstands Kant. My analysis also contains a positive aspect, for I adopt Beck’s claim that there is only one possible standpoint from which critical philosophy ought to be judged. Unlike Beck, I shall argue that this standpoint is that of Judgment’s normativity. I will consider the normative structure of Judgment from three perspectives: the proto-synthetic import of sensibi…

On Computability of Decaying and Nondecaying States in Quantum Systems with Cantor Spectra

2003

We study Hamiltonians with singular spectra of Cantor type with a constant ratio of dissection. The decay properties of the states in such systems depend on the nature of the dissection rate that can be characterized in terms of the algebraic number theory. We show that in spite of simplicity of the considered model the computational modeling of nondecaying states is in general impossible.

Application of dictionary learning to denoise LIGO’s blip noise transients

2020

Data streams of gravitational-wave detectors are polluted by transient noise features, or ``glitches,'' of instrumental and environmental origin. In this work we investigate the use of total variation methods and learned dictionaries to mitigate the effect of those transients in the data. We focus on a specific type of transient, ``blip" glitches, as this is the most common type of glitch present in the LIGO detectors and their waveforms are easy to identify. We randomly select 100 blip glitches scattered in the data from advanced LIGO's O1 run, as provided by the citizen-science project Gravity Spy. Our results show that dictionary-learning methods are a valid approach to model and subtrac…