Lattices Research Papers - Academia.edu (original) (raw)

Abstract— This paper presents an adaptive control scheme for suppressing jitter in laser beams. The variable-order adaptive controller is based on an adaptive lattice filter that implicitly identifies the disturbance statistics from... more

Abstract— This paper presents an adaptive control scheme for suppressing jitter in laser beams. The variable-order adaptive controller is based on an adaptive lattice filter that implicitly identifies the disturbance statistics from real-time sensor data. The multi-channel adaptive ...

Quantum logic gates require qubits that can interact strongly with each other and with external fields while minimizing unwanted coupling to the decohering environment. Neutral atoms trapped in a far-off resonance optical lattice satisfy... more

Quantum logic gates require qubits that can interact strongly with each other and with external fields while minimizing unwanted coupling to the decohering environment. Neutral atoms trapped in a far-off resonance optical lattice satisfy these criteria. The adjustable parameters of the lattice (e.g., laser polarization, frequency, intensity) allow one to design interactions for which atoms interact strongly via dipole-dipole interactions

This paper proposes a security architecture for optical code division multiple access networks based on lattice cryptography. Unlike existing approaches, which have mainly focused on optical components such as phase masks and delay lines,... more

This paper proposes a security architecture for optical code division multiple access networks based on lattice cryptography. Unlike existing approaches, which have mainly focused on optical components such as phase masks and delay lines, our cryptosystem encompasses a secure code construction process. In fact, given a set of optical orthogonal codewords, we associate a pair of bases (a public basis and a private basis) to every user and we show that the projection of a codeword on the public basis of the receiver and the addition of a random error enhances the confidentiality performance of the code. The proposed public key cryptosystem is based on lattice cryptography. The security of this scheme relies mainly on the complexity of the closest vector-problem in an integer lattice. We found that our technique performs better than the existing approaches in terms of robustness to cryptanalysis. We also study the security of our lattice cryptosystem with regard to the properties of the bases pairs and the error vectors.

• Develop LBM performance to simulate the heat flux of heat source. • Natural convection and mixed convection of inclined driven cavity by LBM. • Modify collision operator and macroscopic velocities equations in LBM. a b s t r a c t Nano... more

• Develop LBM performance to simulate the heat flux of heat source. • Natural convection and mixed convection of inclined driven cavity by LBM. • Modify collision operator and macroscopic velocities equations in LBM. a b s t r a c t Nano scale method of lattice Boltzmann is developed to predict the fluid flow and heat transfer of air through the inclined lid driven 2-D cavity while a large heat source is considered inside it. Two case studies are supposed: first one is a pure natural convection at Grashof number from 400 to 4000 000 and second one is a mixed convection at Richardson number from 0.1 to 10 at various cavity inclination angles. Using LBM to simulate the constant heat flux boundary condition along the obstacle, is presented for the first time while the buoyancy forces affect the velocity components at each inclination angle; hence the collision operator of LBM and also a way to estimate the macroscopic velocities should be modified. Results are shown in the terms of streamlines and isotherms, beside the profiles of velocity, temperature and Nusselt number. It is observed that the present model of LBM is appropriately able to simulate the supposed domain. Moreover, the effects of inclination angle are more important at higher values of Richardson number.

An important computational problem in color imaging is the design of color transforms that map color between devices or from a device-dependent space (e.g., RGB/CMYK) to a device-independent space (e.g., CIELAB) and vice versa. Real-time... more

An important computational problem in color imaging is the design of color transforms that map color between devices or from a device-dependent space (e.g., RGB/CMYK) to a device-independent space (e.g., CIELAB) and vice versa. Real-time processing constraints entail that such nonlinear color transforms be implemented using multidimensional lookup tables (LUTs). Furthermore, relatively sparse LUTs (with efficient interpolation) are employed in practice because of storage and memory constraints. This paper presents a principled design methodology rooted in constrained convex optimization to design color LUTs on a simplex topology. The use of n simplexes, i.e., simplexes in n dimensions, as opposed to traditional lattices, recently has been of great interest in color LUT design for simplex topologies that allow both more analytically tractable formulations and greater efficiency in the LUT. In this framework of n-simplex interpolation, our central contribution is to develop an elegant iterative algorithm that jointly optimizes the placement of nodes of the color LUT and the output values at those nodes to minimize interpolation error in an expected sense. This is in contrast to existing work, which exclusively designs either node locations or the output values. We also develop new analytical results for the problem of node location optimization, which reduces to constrained optimization of a large but sparse interpolation matrix in our framework. We evaluate our n -simplex color LUTs against the state-of-the-art lattice (e.g., International Color Consortium profiles) and simplex-based techniques for approximating two representative multidimensional color transforms that characterize a CMYK xerographic printer and an RGB scanner, respectively. The results show that color LUTs designed on simplexes offer very significant benefits over traditional lattice-based alternatives in improving color transform accuracy even with a much smaller number- of nodes.

Lattice-based signature schemes following the Goldreich–Goldwasser–Halevi (GGH) design have the unusual property that each signature leaks information on the signer’s secret key, but this does not necessarily imply that such schemes are... more

Lattice-based signature schemes following the Goldreich–Goldwasser–Halevi (GGH) design have the unusual property that each signature leaks information on the signer’s secret key, but this does not necessarily imply that such schemes are insecure. At Eurocrypt ’03, Szydlo proposed a potential attack by showing that the leakage reduces the key-recovery problem to that of distinguishing integral quadratic forms. He proposed a

Sentence word segmentation and Part-Of-Speech (POS) tagging are common preprocessing tasks for many Natural Language Processing (NLP) applications. This paper presents a practical application for POS tagging and segmentation... more

Sentence word segmentation and Part-Of-Speech (POS) tagging are common preprocessing tasks for many Natural Language Processing (NLP) applications. This paper presents a practical application for POS tagging and segmentation disambiguation using ...

We explore the lattice sphere packing representation of a multi-antenna system and the algebraic space-time (ST) codes. We apply the sphere decoding (SD) algorithm to the resulted lattice code. For the uncoded system, SD yields, with... more

We explore the lattice sphere packing representation of a multi-antenna system and the algebraic space-time (ST) codes. We apply the sphere decoding (SD) algorithm to the resulted lattice code. For the uncoded system, SD yields, with small increase in complexity, a huge improvement over the well-known V-BLAST detection algorithm. SD of algebraic ST codes exploits the full diversity of the coded multi-antenna system, and makes the proposed scheme very appealing to take advantage of the richness of the multi-antenna environment. The fact that the SD does not depend on the constellation size, gives rise to systems with very high spectral efficiency, maximum-likelihood performance, and low decoding complexity.

The basis for a theory of porous electrodes is the percolation problem. Its solution would make it possible to answer the question of how effectively the structure of a porous electrode is used for ensuring the occurrence of... more

The basis for a theory of porous electrodes is the percolation problem. Its solution would make it possible to answer the question of how effectively the structure of a porous electrode is used for ensuring the occurrence of electrochemical processes on its inner surface, for bringing together all its participants (reagents, ions, electrons, catalyst particles), and for removing the formed products. For the solution of this problem, it is necessary that both the elements of the structure of a porous electrode and the substances filling it should be connected. In the case of hydrophobized electrodes, these are exemplified by a mixture of agglomerated grains of polytetrafluoroethylene and catalyst, the gaseous reagent entering the electrons, and the electrolyte. In this publication, we describe a general method intended for the calculation of thresholds and lines of percolation and present particular estimates for an important class of lattices modeling porous media – rectangular: plane, square lattice, three-dimensional cubic, and their analogues in space of any number of measurements.