patchIT: A Multipurpose Patch Creation Tool for Image Processing Applications

Patch-based approaches in image processing are often preferable to working with the entire image. They provide an alternative representation of the image as a set of partial local sub-images (patches) which is a vital preprocessing step in many image processing applications. In this paper, a new software tool called patchIT is presented, providing an integrated framework suitable for the systematic and automatized extraction of patches from images based on user-defined geometrical and spatial criteria. Patches can be extracted in both a sliding and random manner and can be exported either as images, MATLAB .mat files, or raw text files. The proposed tool offers further functionality, including masking operations that act as spatial filters, identifying candidate patch areas, as well as geometric transformations by applying patch value indexing. It also efficiently handles issues that arise in large-scale patch processing scenarios in terms of memory and time requirements. In addition, a use case in cartographic research is presented that utilizes patchIT for map evaluation purposes based on a visual heterogeneity indicator. The tool supports all common image file formats and efficiently processes bitonal, grayscale, color, and multispectral images. PatchIT is freely available to the scientific community under the third version of GNU General Public License (GPL v3) on the GitHub platform

Random vibration of linear systems with singular matrices based on Kronecker canonical forms of matrix pencils

A novel technique is developed for determining the stochastic response of linear dynamic systems with singular parameter matrices based on matrix pencil theoretical concepts and relying on Kronecker canonical forms (KCF). The herein developed solution technique can be construed as a generalization of the standard linear random vibration theory and tools to account for constraints in the system dynamics and for singular system parameter matrices. Further, in comparison with alternative generalized matrix inverse approaches providing a family of possible solutions, the KCF-based technique yields a unique solution. This is an additional significant advantage of the technique since the use of pseudo-inverses is circumvented, and the challenge of selecting an optimal solution among a family of possible ones is bypassed. Various diverse examples are considered for demonstrating the versatility and validity of the technique. These pertain to structural (multi-body) systems modeled by dependent degrees-of-freedom, energy harvesters with coupled electromechanical equations, and oscillators subject to non-white excitations described by additional auxiliary state equations acting as filters to white noise. © 2021 Elsevier Lt

A chaotic path planning generator based on logistic map and modulo tactics

A simple, short and efficient chaotic path planning algorithm is proposed for autonomous mobile robots, with the aim of covering a given terrain using chaotic, unpredictable motion. The proposed technique utilizes the logistic map with a chaotic tactic that utilizes a modulo function to produce a sequence of directions for a robot that can move in eight different directions on a grid. Extensive simulations are performed, and the results show a fast and efficient scanning of the given area. In addition, the proposed algorithm is further enhanced with a pheromone inspired memory technique, with good improvements in efficiency. © 2019 Elsevier B.V

Varying-parameter finite-time zeroing neural network for solving linear algebraic systems

A new recurrent neural network is presented for solving linear algebraic systems with finite-time convergence. The proposed model includes an exponential term in the Zhang neural network dynamical system, which leads to a faster convergence of the error-monitoring function in comparison to previous methods. Theoretical analysis, as well as simulation results, validate the efficacy of the proposed model. © The Institution of Engineering and Technology 2020 Submitted: 23 January 2020 E-first: 22 June 202

Analysis, Synchronization, and Robotic Application of a Modified Hyperjerk Chaotic System

In this work, a novel hyperjerk system, with hyperbolic sine function as the only nonlinear term, is proposed, as a modification of a hyperjerk system proposed by Leutcho et al. First, a dynamical analysis on the system is performed and interesting phenomena concerning chaos theory, such as route to chaos, antimonotonicity, crisis, and coexisting attractors, are studied. For this reason, the system's bifurcation diagrams with respect to different parameter values are plotted and its Lyapunov exponents are computed. Afterwards, the synchronization of the system is considered, using active control. The proposed system is then applied, as a chaotic generator, to the problem of chaotic path planning, using a combination of sampling and a modulo tactic technique. © 2020 Lazaros Moysis et al

A 1D coupled hyperbolic tangent chaotic map with delay and its application to password generation

This paper proposes a new one-dimensional chaotic map. The map consists of a coupling between two hyperbolic tangent terms, where the second term is delayed, to avoid dynamical degradation. The map is studied through computation of its bifurcation diagrams and Lyapunov exponent diagrams and is shown to have constant chaotic behavior for almost all parameter values. Afterward, based on the proposed map, a pseudo-random bit generator with a high keyspace is designed. This generator is then used as a basis for a proposed password generator application. The motivation behind this application is to design an algorithm that takes as input an easy-to-remember key by the user and outputs a secure password that can be used for websites or file security. This way, the use of easy-to-crack, repetitive passwords is avoided. The proposed generator is developed as a graphical user interface. © 2022, The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature

A chaotic path planning generator enhanced by a memory technique

This work considers the problem of chaotic path planning, using an improved memory technique to boost performance. In this application, the dynamics of two simple chaotic maps are first used to generate a pseudo-random bit generator. Using this as a source, a series of navigation commands are generated and used by an autonomous robot to explore an area, while maintaining a random and unpredictable motion. This navigation strategy can bring overall area coverage, but also yields numerous revisits to previous cells. Here, a memory technique is applied to limit the chaotic motion of the robot to adjacent cells with the least number of visits, leading to overall improvement in performance. Numerical simulations are performed to evaluate the path planning strategy. The simulation results showcase a major improvement in coverage performance compared to the memory-free technique and also compared to an inverse pheromone technique previously developed by the authors. Also, the number of multiple visits to previous cells is significantly reduced with the proposed technique. © 2021 Elsevier B.V

Chaotic path planning for grid coverage using a modified logistic-may map

A simple and efficient method for creating a motion trajectory is presented with an aim to achieve sufficient coverage of a given terrain. A chaotic map has been used in order that the motion trajectory should be unpredictable. The chaotic path generator which has been created, is used for implementing a robot’s movement in four and eight directions. The path generator is tested in various scenarios and the results are discussed. After thorough examination, the proposed method shows that the motion in eight directions gives better and very satisfactory results. © 2020, Industrial Research Institute for Automation and Measurements. All rights reserved

A two-parameter modified logistic map and its application to random bit generation

This work proposes a modified logistic map based on the system previously proposed by Han in 2019. The constructed map exhibits interesting chaos related phenomena like antimonotonicity, crisis, and coexisting attractors. In addition, the Lyapunov exponent of the map can achieve higher values, so the behavior of the proposed map is overall more complex compared to the original. The map is then successfully applied to the problem of random bit generation using techniques like the comparison between maps, XOR, and bit reversal. The proposed algorithm passes all the NIST tests, shows good correlation characteristics, and has a high key space. © 2020 by the authors