Le séchage des dispersions colloïdales a été et demeure très étudié en raison de son extrême complexité et de son utilisation dans de nombreuses applications. Dans cette thèse, nous avons développé une simulation, d'abord unidirectionnelle, basée sur le principe des automates cellulaires, qui traite la problématique du séchage horizontal et vertical. Ce travail permet de prédire, par calcul numérique, la distribution des particules et la position des fronts de séchage dans les dépôts de dispersions sous forme de films minces. Nos résultats ont montré que la pression existant dans le fluide est la somme des pressions de Laplace et hydrostatique. Par rapport aux modèles existants, cela modifie la convection des particules dans la partie fluide de la dispersion. La diffusion collective des particules chargées a été étudiée également. Contrairement aux prédictions théoriques antérieures, nous avons pu montrer que la diffusion collective des particules chargées pouvait jouer un rôle majeur, y compris dans le cadre de l’approximation de lubrification. Finalement, la simulation 1D a été étendue en 2D, ce qui a permis de comprendre la raison pour laquelle deux fronts dans deux directions perpendiculaire (cas d’une géométrie rectangulaire) avancent à des vitesses différentes. Une comparaison entre les données expérimentales et le calcul numérique sur le profil du film et la vitesse des fronts de séchage pour une dispersion de silice montre un bon accord. / Drying of colloidal dispersions, given their uses in several fields in everyday life, has been the subject of many studies for a long time. In this thesis, we first developed an unidirectional simulation, based on the principle of the cellular automaton, which deals with the problem of horizontal and vertical drying. This work makes it possible to predict, by numerical calculation, the distribution of the particles and the position of drying fronts in deposits in form of thin films.The profile of the film in the liquid part was studied. Our results have shown that the pressure in the fluid is the sum of the Laplace and hydrostatic pressures. This result affects the dynamics of particles in the fluid part of the dispersion, in particular convection. The collective diffusion of charged particles has also been studied. Contrary to what was predicted in previous theoretical models, we were able to show that the collective diffusion of the charged particles could be important even within the lubrication approximation. Finally, the 1D simulation was extended to 2D in order to understand the reason why two fronts in perpendicular directions (case of a rectangular geometry) advance at different speeds. A comparison between the experimental data for the drying of a silica dispersion and the numerical calculation shows good agreement.

Tato disertační práce je zaměřena na vysokorychlostní simulace dopravy a jejich přesnou kalibraci pomocí různých typů dopravních dat. Práce se po úvodním popisu motivace pro samotný výzkum nejdříve věnuje současnému stavu poznání, a dále rozdělení simulátorů dopravy, zejména podle typu dat, se kterými se v nich pracuje. Úpravou existujícího řešení je navržen vlastní mikrosimulační model, který je založen na principu celulárního automatu. S tímto novým modelem je pak experimentováno, zpočátku z pohledu rychlosti simulace a další rozšiřitelnosti. Je navržena a popsána technika, kterou je možné navržený model významně akcelerovat a následně provádět simulace rychleji než v reálném čase i pro rozsáhlá území. Práce dále přistupuje k samotné kalibraci modelu, ke které byl využit evoluční přístup. Je představena metoda pro efektivní způsob optimalizace parametrů mikrosimulačního modelu, která nevyžaduje citlivostní analýzu a je schopná nalézt jinak obtížně nastavitelné parametry modelu. Kvalita získaných optimalizovaných modelů byla analyzována jak pomocí makroskopických, tak i mikroskopických dopravních dat, a to i s ohledem na jejich reálné vlastnosti, tj. chybějící vzorky. Dále jsou zhodnoceny výkonnostní a jiné kvalitativní parametry vlastního přístupu v porovnání s existujícími řešeními, přičemž bylo dosaženo významného zlepšení. Nakonec jsou představeny nástroje, které v rámci řešení vznikly. Na závěr je uvedeno další zaměření výzkumu, a to zejména s ohledem na využití výsledků práce v praxi.

The main goal of the work is to introduce new ideas how traditional approaches for designing an operation system and associated software can be improved to be a part of automatic software evolution. It is generally supposed that algorithms found by the genetic programming processes cannot be used for exact calculations but only for approximate solutions. Several examples of software evolution are introduced, to show that quite precise solutions can be achieved. To reach this goal, characteristics of tree-like structures with approaches based on cellular automata features are combined in a new promising technique of algorithm representation, joining benefits of both concepts. An application has been developed based on these new genetic programming concepts and it is supposed it can be a part of a future automatic software evolution process.

This thesis main focus is microscopic traffic sumulation. Part of this work is the design and implementation of microsimulation model based on cellular automaton. Implemented model supports calibration with genetic algorithm. The results of calibration and simulations are included.

The aim of this paper is to introduce the readers to the field of cellular automata, their design and their usage for structural design. Genetic algorithms are usually involved in designing complicated cellular automata, and because of that they are also briefly described here. For the purposes of this work sorting networks are considered as suitable structures to be designed using cellular automata, however, they are not a part of the automata but they are generated separately by modified rules of a local transition function.

This master's thesis deals with cellular automata and further deals possibility of their global control. It describes the implementation of simulator of globally controlled cellular automata. The goal is, design and test the classification of globally controlled cellular automata. Classification is based on evaluation of influence of each parameter of automata on their dynamics.

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In the United States, intersections are among the most frequent locations for crashes. One of the major problems at signalized intersection is the dilemma zone, which is caused by false driver behavior during the yellow interval. This research evaluated driver behavior during the yellow interval at signalized intersections and compared different dilemma zone countermeasures. The study was conducted through four stages. First, the driver behavior during the yellow interval were collected and analyzed. Eight variables, which are related to risky situations, are considered. The impact factors of drivers' stop/go decisions and the presence of the red-light running (RLR) violations were also analyzed. Second, based on the field data, a logistic model, which is a function of speed, distance to the stop line and the lead/follow position of the vehicle, was developed to predict drivers' stop/go decisions. Meanwhile, Cellular Automata (CA) models for the movement at the signalized intersection were developed. In this study, four different simulation scenarios were established, including the typical intersection signal, signal with flashing green phases, the intersection with pavement marking upstream of the approach, and the intersection with a new countermeasure: adding an auxiliary flashing indication next to the pavement marking. When vehicles are approaching the intersection with a speed lower than the speed limit of the intersection approach, the auxiliary flashing yellow indication will begin flashing before the yellow phase. If the vehicle that has not passed the pavement marking before the onset of the auxiliary flashing yellow indication and can see the flashing indication, the driver should choose to stop during the yellow interval. Otherwise, the driver should choose to go at the yellow duration. The CA model was employed to simulate the traffic flow, and the logistic model was applied as the stop/go decision rule. Dilemma situations that lead to rear-end crash risks and potential RLR risks were used to evaluate the different scenarios. According to the simulation results, the mean and standard deviation of the speed of the traffic flow play a significant role in rear-end crash risk situations, where a lower speed and standard deviation could lead to less rear-end risk situations at the same intersection. High difference in speed are more prone to cause rear-end crashes. With Respect to the RLR violations, the RLR risk analysis showed that the mean speed of the leading vehicle has important influence on the RLR risk in the typical intersection simulation scenarios as well as intersections with the flashing green phases' simulation scenario. Moreover, the findings indicated that the flashing green could not effectively reduce the risk probabilities. The pavement marking countermeasure had positive effects on reducing the risk probabilities if a platoon's mean speed was not under the speed used for designing the pavement marking. Otherwise, the risk probabilities for the intersection would not be reduced because of the increase in the RLR rate. The simulation results showed that the scenario with the pavement marking and an auxiliary indication countermeasure, which adds a flashing indication next to the pavement marking, had less risky situations than the other scenarios with the same speed distribution. These findings suggested the effectiveness of the pavement marking and an auxiliary indication countermeasure to reduce both rear-end collisions and RLR violations than other countermeasures.

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