Jiří Kroc

Jiří Kroc
Independent Researcher · Complex Systems & Theory in Physics, Biology, and Medicine

Ph.D., Computational & Solid State Physics
Complex systems, emergence, self-organization, theory of massive-parallel computations in science, biology & medicine.

About

46
Publications
63,111
Reads
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268
Citations
Introduction
The scientific effort is focussed into the following directions: (i) application of Complex Systems in medical and biological research, (ii) to provide an easy to follow explanation of mathematical aspects of Complex Systems and their use in biosciences, (iii) search for prospective research areas using advanced computational techniques and theories and sharing them with all researchers, (iv) providing predictive tools enabling the therapies of patients.
Additional affiliations
February 2015 - December 2017
Charles University in Prague
Position
  • Researcher
Description
  • Applications of Complex Systems in Biology and Medicine - Prediction of Arrhythmias
October 2003 - November 2003
Helsinki School of Economics
Position
  • visiting professor
Description
  • Intensive Course on Business Mathematics
November 2002 - December 2002
Helsinki School of Economics
Position
  • visiting professor
Description
  • Intensive Course on Complex Systems
Education
October 1995 - April 1999
Charles University in Prague
Field of study
  • Solid State Physics
September 1987 - October 1994
Charles University in Prague
Field of study
  • Mathematical & Computational Modeling in Physics

Publications

Publications (46)
Code
The purposes of this software are manifold: (i) It serves as an introduction to the modeling of dynamic recrystallization by cellular automata and to complex systems modeling by cellular automata in general. (ii) There is a big demand to have in hands an open-source software that can serve as an example to similar software that might be developed i...
Preprint
Full-text available
This review aims mainly to all professionals from the fields of clinical medicine, biomedical and experimental research. It targets to deliver a quick starting overview and basic understanding of Complex Systems (CSs) with a citation apparatus enabling to efficiently reach the cutting-edge knowledge and applications. This paper has two main objecti...
Article
Cellular automaton models of complex systems (CSs) are gaining greater popularity; simultaneously, they have proven the capability to solve real scientific and engineering applications. To enable everybody a quick penetration into the core of this type of modeling, three real applications of cellular automaton models, including selected open source...
Preprint
Full-text available
Background: In general, this methodical paper describes a well documented application of one complexity measure and various machine learning methods to solve a specific problem in biosignal processing: predictions of ventricular tachycardias & fibrillations, and Torsades de Pointes arrhythmias. The methodology is enhanced by a concise introduction...
Preprint
Full-text available
The current frontiers in the description and simulation of advanced physical and biological phenomena observed within all scientific disciplines are pointing directly toward the importance of development of robust mathematical descriptions that are error resilient. Complexity research is lacking deeper knowledge of the design methodology of process...
Code
TBA later. Apologies to any inconvenience with mizsing code. Please, follow the page, the code will be added later. Preliminary result of the code run is shown at the link: https://www.researchgate.net/publication/357285926_Python_program_simulating_cellular_automaton_r-GoL_that_represents_robust_generalization_of_%27Game_of_Life%27_sample_runs...
Data
This is a preliminary research output, which occurred as a side result during research on modifications of the 'Game of Life' proposed by John Conway. Such scientifically and visually appealing simulation had arisen among many others where the observed structures might be interesting to other researchers. More will appear in a couple of months, sta...
Data
The whole computer can be simulated using the cellular automaton called the 'Game of the Life' that was designed by John Conway in 1970 using emergent structures of the first order. Presented simulations aim to demonstrate that environments utilizing massive parallel computations (MPC) including living organisms can carry on Turing Machine equivale...
Code
This program serves as an introduction into complex systems modeling. The GoL was developed by John Conway in the 70ies, and it gained a huge attention by both researchers and mathematical enthusiasts. In the past, such programs designed in some higher-level programming language can easily exceed thousands of code lines. This program has about one...
Code
Demo video (snapshot included) showing the running program ECG-pyview that displays single lead ECG recordings. The video depicts the whole procedure that starts by running a sample ECG recording on a command line and ends by demonstration of all capabilities of the program. Manipulation of the sliders managing time and time window width are shown....
Code
This Python software enables everyone to visualize single lead ECG recordings that are having lengths going from tens of second up to days. Extra long files can be split in smaller segments to avoid the memory overflow and processor overload. It is very suitable to make a quick assessment of ECG recordings taken in emergency cases and during sport...
Data
In this document, we explain diagrams commonly used in software engineering. We included graphical representation of each diagram to help you understand the main aspects of the program faster and easier. Additional documentation is located directly in the program code, mainly in files with ".h" extensions. Link to source code: ( https://www.resear...
Data
This page contains the executable version of the project [ https://www.researchgate.net/publication/316989956_Cellular_Automaton_Simulation_of_Dynamic_Recrystallization_Introduction_into_Self-Organization_and_Emergence ] for the MacOS system. Creating the executable package for MacOS was done by @Peter_Bocan. For details about the project, please,...
Research
Full-text available
This video presents numerical experiments done by the software "Cellular Automaton Simulation of Dynamic Recrystallization: Introduction" (https://www.researchgate.net/publication/316989956_Cellular_Automaton_Simulation_of_Dynamic_Recrystallization_Introduction). This software was developed by Jakub Tkac according to the original software that was...
Code
For all who needs to automatically generate figures fast and repeatedly from hundreds of ASCII input files, an example is provided using BASH shell under LINUX OS. Once programmed, such software can save days of tedious work. It runs in no time when compared to the creation of figures in Excell or Gnuplot by hand. A generic example of a script disp...
Poster
Full-text available
The theory of Complex Systems (CSs) is offering new mathematical concepts of definition, description, and evaluation of biological systems. A number of vital mathematical descriptions that are constantly developing within CSs increasingly assist biomedical research. The main goal of the presentation is to increase awareness of medical researchers a...
Research
Full-text available
The animation, representing a simulation generated by the Qt front-end, of the program published at the RG-page under name "Design and Implementation of Cellular Automaton Simulating Domain Growth - Source Code" (https://www.researchgate.net/publication/303805779_Design_and_Implementation_of_Cellular_Automaton_Simulating_Domain_Growth_-_Source_Code...
Code
The bachelor thesis is focused to design and implementation of the Qt graphical user interface of cellular automaton simulating domain decomposition by employing a self-organization principle. The main goal is to enable everybody to achieve a better understanding of complex systems modelling principles, which are explained on an example dealing wit...
Data
This is a snapshot from the model presented in the paper "Diffusion Controlled Cellular Automaton Performing Mesh Partitioning". Domains are having the same area. This final state is a dynamic equilibrium of competing process presented within a model. Each pixel of the picture can be viewed as a living cell, organism, species, etc. (details at: ht...
Experiment Findings
Full-text available
This is a quick introduction to the topic in an animated form. It gives you the impression of a living thing. The original idea of this software arrived when the author was thinking about cell growth. Similar effects are observed in all living organisms. For details, see the paper, book chapter, and software that is open under the GPL license. (To...
Data
This supplement material is about how this paper might be understood from the biological point of view. Although the developed algorithm is applied within the field of computer science, the original motivation of it comes from biology. Originally, there was an initial idea of growth of living cells, bacterial colonies, or animal herds—beside other...
Book
Full-text available
>>> The best seller in the field - over 30k ebooks sold as 2018. <<< From the Back Cover: Deeply rooted in fundamental research in Mathematics and Computer Science, Cellular Automata (CA) are recognized as an intuitive modeling paradigm for Complex Systems. Already very basic CA, with extremely simple micro dynamics such as the Game of Life, show...
Chapter
Full-text available
>>>>> Introduction into the best selling book in the field - over 30k ebooks sold. <<<<< Abstract: Since the sixteenth century there have been two main paradigms in the methodology of doing science. The first one is referred to as “the experimental” paradigm. During an experiment we observe, measure, and quantify natural phenomena in order to solve...
Chapter
Full-text available
In recent years, the notion of complex systems proved to be a very useful concept to define, describe, and study various natural phenomena observed in a vast number of scientific disciplines. Examples of scientific disciplines that highly benefit from this concept range from physics, mathematics, and computer science through biology and medicine as...
Research
Full-text available
Nature seems to be able to process information on many spatial and temporal scales simultaneously without any external control, coordination or 'processing unit'. Understanding and interpreting the underlying computational process is one of the biggest challenges of computational science. In this paper, we propose a novel computational paradigm, na...
Chapter
Computational modelling of morphological development of tissues based on complex systems and cellular automata can be decomposed into three interdependent processes. Those three crucial parts are mechanical response of tissues, diffusion of signalling molecules, and gene regulatory network. It is shown that development of an adequate mechanical mod...
Article
Full-text available
A model of morphological development of living tissues could be split into three mutually entangled parts: a mechanical model of tissues, diffusion of signaling molecules, and a gene regulatory network. This paper propose a cellular automaton mechanical model of mesenchyme including its growth caused by proliferation of cells. The main attention is...
Article
Full-text available
This special journal issue of Advances in Complex Systems presents a collection of papers describing current research delivered by recognized researchers actively working in various corners of the field of modeling of complex systems by cellular automata and related methods. All included papers are self-contained and present the latest developments...
Chapter
Full-text available
Properties of the model performing dynamic mesh partitioning into computationally equivalent mesh parts on regular square lattices using the diffusion controlled cellular automaton (DCCA) are studied. Every processor has assigned a domain seed at the beginning of each simulation--seeds grow into competing domains having migrating boundaries. Comput...
Conference Paper
Full-text available
Developmental biology describes how tissues, organs, and bodies are made from living cells. There exists a large body of biological data about developmental processes but there is still not ultimate understanding of how the whole orchestra of all involved processes is working. It is the place where mathematical modelling could help to create biolog...
Article
Four cellular automata rules performing two-colouring of square tiled planes are proposed – where those deterministic, self-organizing local rules ensure that no two squares having the same colour could touch each other by their common edge. The speed of the first rule could be lowered by creation of a number of anti-phase separation borders – appe...
Article
This paper continues in the previous research focussed to two simple ques-tions. The first one reads: "What is the influence of anisotropy of computational lattice on simulations of boundary movement?" where grain boundary movement typically appears in simulations of grain boundary migration and static/dynamic recrystallization. The sec-ond questio...
Conference Paper
Full-text available
A model performing mesh partitioning into computationally equivalent mesh parts on regular square lattices using a diffusion controlled cellular automaton (DCCA) is proposed and studied in this article. Every processor has assigned a domain seed at the beginning of a simulation. Algorithm works with growth of seeds and migration of domain borders,...
Article
This paper try to elucidate some aspects of the impact of using two different types of computational lattices on the solution of simple models like, for example, grain boundary migration and/or dynamic recrystallization.Not surprisingly, the final solution is obviously affected by anisotropy of used lattices but as we know, they are computational l...
Article
Full-text available
Within past ten years, the importance of cellular automata (CA) models of both recrystallization and grain boundary migration has been recognized. It can be shown that CA provides a computationally efficient mathematical framework for simulations of physically relevant models of the above processes. Generally, CA works in such models with a vast nu...
Conference Paper
Full-text available
Propagation of excitation waves and their mutual interactions on the surface layer of a ball with fast accessory paths and pacemaker is studied by the cellular automaton (CA) computer simulation technique in three—dimensions. The existence of the conducting system created by fast accessory paths and the pacemaker in the excitable medium — i.e., in...
Conference Paper
Full-text available
The cellular automaton computer simulation technique has been applied to the problem of dynamic recrystallization. The model is composed of simple microstructural mechanisms - such as evolution of dislocation density, grain boundary movement and nucleation - that acting together result in complex macrostructural response expressed by evolution of f...
Article
Full-text available
The paper deals with the finite element macroscopic model of contracting myocard-ium. The constitutive model of the tissue is based on the theory of mixtures, involving a simple model of intramyocardial blood perfusion. Anisotropy of the tissue is described in terms of preferential directions of the muscle and connective fibres. A simple Hill-type...
Article
Changes of the grain shapes caused by the grain boundary migration are modelled by a cellular automaton in a quadricrystal. It is shown that a simple local transition rule is sufficient to describe the grain boundary migration also in the configurations containing triple junctions. A process during which two grains shrink and finally disappear is q...
Thesis
Full-text available
It is well known that many of macroscopic properties of materials undergoing dynamic recrystallization are determined by their microstructure. Despite a large experimental and theoretical effort, it is not possible to predict in a satisfactory way the evolution of microstructure with sufficient precision. The reason is that we are dealing with a co...
Article
This paper presents simulation of the work hardening curves of metals deformed at a constant temperature and strain rate under conditions of dynamic recrystallization (DRX). A work hardening model has been developed based on the evolution of the dislocation structure during deformation. A statistical approach is used to predict the microstructure e...
Conference Paper
Full-text available
Compression tests at elevated temperature, including 'constant structure' tests, to simulate the deformation strength (stress-rate relation). See abstract below.

Questions

Questions (12)
Question
Complex systems are becoming one of very useful tools in the description of observed natural phenomena across all scientific disciplines. You are welcomed to share with us hot topics from your own area of research.
Nowadays, no one can encompass all scientific disciplines. Hence, it would be useful to all of us to know hot topics from various scientific fields.
Discussion about various methods and approaches applied to describe emergent behavior, self-organization, self-repair, multiscale phenomena, and other phenomena observed in complex systems are highly encouraged.

Network

Cited By

Projects

Projects (8)
Project
The current highly interdisciplinary research is revealing the fundamental role of electromagnetic waves in the functioning of living entities. This project will cover research going from Quantum Fied Theory, across DNA synthesis, biochemical reactions, electromagnetic properties off cell, tissues, organs, and bodies, and end with the healthy or diseased function of living entities.
Project
1. Sharing & recommending publications. 2. Connecting with colleagues. 3. Seeking new collaborations. Внедрение на нашей планете предложенного и разработанного автором источника чистой энергии-нано-энергетики Шестого экономического уклада -единственного в мире безвредного, возобновляемого, эффективного, воспроизводимого, устойчивого и дешевого источника энергии даёт возможность выжить человечеству в замкнутом пространстве тропосферы на планете Земля в условии чрезвычайного отравления атмосферы отходами производства промышленности-отходящими газами и запредельными количествами промышленных и бытовых отходов на поверхности планеты, сохранив при этом иммунитет населения, так как топливом для предложенной Кулаковым нано энергетики новой технологической парадигмы являются все отходы жизнедеятельности самого же человечества.
Project
To collect relevant scientific understanding, data, models, solutions, and certifications for Covid-19 caused by the SARS-CoV-2. Together we can learn more than when working alone.