THREE-DIMENSIONAL VISUALIZATION OF MOLECULAR ORGANIZATION AND PHASE TRANSITIONS IN LIQUID CRYSTAL LATTICE MODELS

1992 ◽  
Vol 03 (06) ◽  
pp. 1209-1220 ◽  
Author(s):  
CESARE CHICCOLI ◽  
PAOLO PASINI ◽  
FRANCO SEMERIA ◽  
CLAUDIO ZANNONI
Keyword(s):  
Monte Carlo ◽  
Liquid Crystal ◽  
Crystal Lattice ◽  
Personal Computer ◽  
Three Dimensional ◽  
Lattice Models ◽  
Point Of View ◽  
Molecular Organization ◽  
Computer Visualization ◽  
Physical Information

An example of three-dimensional animation of Monte Carlo simulation results of liquid crystal lattice models is presented. Molecular configurations are obtained from Monte Carlo simulations on a VAX cluster and downloaded to a 486 personal computer. Visualization of molecular organizations and of their change at a phase transition is obtained by suitable colour coding of orientations and of other relevant physical information on the personal computer, and recorded on a VHS system using a genlock card. The animation sequences generated have a twofold interest: they are useful for educational purposes and, from a scientific point of view, they provide a tool for exploring a large amount of data and investigating the phenomena under study in a non-numerical way.

Liquid Crystal Lattice Models on Quadrics Supercomputers

1997 ◽  
Vol 08 (03) ◽  
pp. 547-554 ◽  
Author(s):  
Sigismondo Boschi ◽  
Marco P. Brunelli ◽  
Claudio Zannoni ◽  
Cesare Chiccoli ◽  
Paolo Pasini
Keyword(s):  
Phase Transition ◽  
Monte Carlo ◽  
Liquid Crystal ◽  
Crystal Lattice ◽  
Applied Field ◽  
Lattice Models ◽  
Massively Parallel ◽  
Isotropic Phase ◽  
Monte Carlo Code

The implementation of a Monte Carlo code for simulations of liquid crystal lattice models on the Quadrics massively parallel SIMD supercomputer is described. The use of a Quadrics with 512 processors is proving essential in studying the nematic–isotropic phase transition to an unprecedented level of accuracy using more than 106 particles. Here some tests on the Lebwohl–Lasher model with and without an applied field are presented.

scholarly journals A Novel (2, 3)-Threshold Reversible Secret Image Sharing Scheme Based on Optimized Crystal-Lattice Matrix

Symmetry ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2063
Author(s):  
Jiang-Yi Lin ◽  
Ji-Hwei Horng ◽  
Chin-Chen Chang
Keyword(s):  
Crystal Lattice ◽  
Three Dimensional ◽  
Lattice Models ◽  
Cover Image ◽  
Secret Image Sharing ◽  
Secret Data ◽  
Secret Image ◽  
Image Sharing ◽  
Sharing Scheme ◽  
Growth Phenomenon

The (k, n)-threshold reversible secret image sharing (RSIS) is technology that conceals the secret data in a cover image and produces n shadow versions. While k (kn) or more shadows are gathered, the embedded secret data and the cover image can be retrieved without any error. This article proposes an optimal (2, 3) RSIS algorithm based on a crystal-lattice matrix. Sized by the assigned embedding capacity, a crystal-lattice model is first generated by simulating the crystal growth phenomenon with a greedy algorithm. A three-dimensional (3D) reference matrix based on translationally symmetric alignment of crystal-lattice models is constructed to guide production of the three secret image shadows. Any two of the three different shares can cooperate to restore the secret data and the cover image. When all three image shares are available, the third share can be applied to authenticate the obtained image shares. Experimental results prove that the proposed scheme can produce secret image shares with a better visual quality than other related works.

Liquid Crystal Lattice Models I. Bulk Systems

2000 ◽  
pp. 99-119 ◽  
Author(s):  
Paolo Pasini ◽  
Cesare Chiccoli ◽  
Claudio Zannoni
Keyword(s):  
Liquid Crystal ◽  
Crystal Lattice ◽  
Lattice Models

A Monte Carlo Simulation of an In-Plane Switching Liquid Crystal Display

1998 ◽  
Vol 09 (03) ◽  
pp. 409-419 ◽  
Author(s):  
Cesare Chiccoli ◽  
Paolo Pasini ◽  
Stefano Guzzetti ◽  
Claudio Zannoni
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Liquid Crystal ◽  
Molecular Interactions ◽  
Liquid Crystal Display ◽  
Molecular Organization ◽  
Switching Effect ◽  
Matrix Approach ◽  
Equilibrium Configurations ◽  
Optical Textures

The Monte Carlo (MC) method is applied to the modeling of a liquid crystal display based on the in-plane switching effect. This is the first attempt to simulate this device features starting from purely microscopic molecular interactions. The optical textures are obtained from the Monte Carlo generated microscopic equilibrium configurations by means of a Müller matrix approach. Suitable order parameters are also calculated to quantify the ordering and the molecular organization across the display cell.

scholarly journals Comparison of Direct and Adjoint k and α-Eigenfunctions

2021 ◽  
Vol 2 (2) ◽  
pp. 132-151
Author(s):  
Vito Vitali ◽  
Florent Chevallier ◽  
Alexis Jinaphanh ◽  
Andrea Zoia ◽  
Patrick Blaise
Keyword(s):  
Monte Carlo ◽  
Monte Carlo Methods ◽  
Energy Transport ◽  
Distinct Point ◽  
Point Of View ◽  
Critical Systems ◽  
Small Deviations ◽  
Power Iteration ◽  
Continuous Energy ◽  
Fission Probability

Modal expansions based on k-eigenvalues and α-eigenvalues are commonly used in order to investigate the reactor behaviour, each with a distinct point of view: the former is related to fission generations, whereas the latter is related to time. Well-known Monte Carlo methods exist to compute the direct k or α fundamental eigenmodes, based on variants of the power iteration. The possibility of computing adjoint eigenfunctions in continuous-energy transport has been recently implemented and tested in the development version of TRIPOLI-4®, using a modified version of the Iterated Fission Probability (IFP) method for the adjoint α calculation. In this work we present a preliminary comparison of direct and adjoint k and α eigenmodes by Monte Carlo methods, for small deviations from criticality. When the reactor is exactly critical, i.e., for k0 = 1 or equivalently α0 = 0, the fundamental modes of both eigenfunction bases coincide, as expected on physical grounds. However, for non-critical systems the fundamental k and α eigenmodes show significant discrepancies.

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