19 research outputs found
Discrepancy and integration in function spaces with dominating mixed smoothness
Optimal lower bounds for discrepancy in Besov spaces with dominating mixed
smoothness are known from the work of Triebel. Hinrichs proved upper bounds in
the plane. In this work we systematically analyse the problem, starting with a
survey of discrepancy results and the calculation of the best known constant in
Roth's Theorem. We give a larger class of point sets satisfying the optimal
upper bounds than already known from Hinrichs for the plane and solve the
problem in arbitrary dimension for certain parameters considering a celebrated
constructions by Chen and Skriganov which are known to achieve optimal
-norm of the discrepancy function. Since those constructions are -adic,
we give -adic characterizations of the spaces. Finally results for
Triebel-Lizorkin and Sobolev spaces with dominating mixed smoothness and for
the integration error are concluded
L_p- and S_{p,q}^rB-discrepancy of (order 2) digital nets
Dick proved that all order digital nets satisfy optimal upper bounds of
the -discrepancy. We give an alternative proof for this fact using Haar
bases. Furthermore, we prove that all digital nets satisfy optimal upper bounds
of the -discrepancy for a certain parameter range and enlarge that
range for order digitals nets. -, - and -discrepancy is considered as well
Quasi-Monte Carlo methods for integration of functions with dominating mixed smoothness in arbitrary dimension
In a celebrated construction, Chen and Skriganov gave explicit examples of
point sets achieving the best possible -norm of the discrepancy function.
We consider the discrepancy function of the Chen-Skriganov point sets in Besov
spaces with dominating mixed smoothness and show that they also achieve the
best possible rate in this setting. The proof uses a -adic generalization of
the Haar system and corresponding characterizations of the Besov space norm.
Results for further function spaces and integration errors are concluded.Comment: arXiv admin note: text overlap with arXiv:1109.454
Adversarial Learning of Mappings Onto Regularized Spaces for Biometric Authentication
We present AuthNet: a novel framework for generic biometric authentication which, by learning a regularized mapping instead of a classification boundary, leads to higher performance and improved robustness. The biometric traits are mapped onto a latent space in which authorized and unauthorized users follow simple and well-behaved distributions. In turn, this enables simple and tunable decision boundaries to be employed in order to make a decision. We show that, differently from the deep learning and traditional template-based authentication systems, regularizing the latent space to simple target distributions leads to improved performance as measured in terms of Equal Error Rate (EER), accuracy, False Acceptance Rate (FAR) and Genuine Acceptance Rate (GAR). Extensive experiments on publicly available datasets of faces and fingerprints confirm the superiority of AuthNet over existing methods
DiffuScene: Denoising Diffusion Models for Generative Indoor Scene Synthesis
We present DiffuScene for indoor 3D scene synthesis based on a novel scene
configuration denoising diffusion model. It generates 3D instance properties
stored in an unordered object set and retrieves the most similar geometry for
each object configuration, which is characterized as a concatenation of
different attributes, including location, size, orientation, semantics, and
geometry features. We introduce a diffusion network to synthesize a collection
of 3D indoor objects by denoising a set of unordered object attributes.
Unordered parametrization simplifies and eases the joint distribution
approximation. The shape feature diffusion facilitates natural object
placements, including symmetries. Our method enables many downstream
applications, including scene completion, scene arrangement, and
text-conditioned scene synthesis. Experiments on the 3D-FRONT dataset show that
our method can synthesize more physically plausible and diverse indoor scenes
than state-of-the-art methods. Extensive ablation studies verify the
effectiveness of our design choice in scene diffusion models.Comment: CVPR 202
