Particulate matter (PM) air pollution is one of the most important topics in the field of environmental protection, and coal strip mining is a significant source of coarse atmospheric aerosol. In order to implement appropriate regulations to improve air quality, we need to identify the major sources of pollution. PM is usually measured in a ground-based manner and its dispersion is only modelled. Therefore, the objective of this study was to measure concentrations of coarse aerosol in the atmospheric boundary layer above the area of the coal strip mine through experimental airborne measurements and to estimate pollution contribution of mining to the surroundings. Measurements were carried out from November 11 to November 26, 2012, at Vršany coal mine, Czech Republic. An electrically powered airship was used with a specially designed gondola carrying aerosol monitors DustTrak DRX and P-Trak. Temperature and relative humidity data were also recorded. Repeated flights were performed at several heights above mine edge level. PM1-10 and GPS data were recorded every second. Average airship velocity ranged from 6 to 7 ms-1 . Flight measurements were also compared to ground-based measurements of PM10 and meteorological data. Weather during our measurements was characterised by low temperatures, high relative...

Dérivants ou submergés, les débris grossiers dérivés de plantes terrestres fournissent de l'énergie et des nutriments pour les écosystèmes marins. En considérant cette matière organique allochtone, l'objectif de ma thèse est de décrire le processus d'assemblage d'une communauté autour d'une ressource trophique et de considérer en retour l'effet de la diversité et de la composition observée au sein de cette communauté sur la dynamique d'exploitation de la ressource. Pour ce faire, j'ai combiné des expériences in situ et la modélisation avec l'intention de parvenir à une description cohérente et quantitative du lien écogéochimique entre la biodiversité et le fonctionnement des écosystèmes. En utilisant de la litière de feuilles et du bois mort, cette approche a permis: (i) de montrer l'importance des interactions biotiques dès le début du processus d'assemblage de la communauté, (ii) de faire le lien explicite entre la consommation des ressources et la dynamique de populations des consommateurs, et (iii) de tester comment la transformation des ressources est affectée par la diversité observée au sein des communautés. / Either adrift or submerged, coarse debris derived from terrestrial plants provide energy and nutrients for marine ecosystems. By considering this allochtonous organic material, the goals of my PhD were to describe the assembly process of macrobenthic communities around food sources and to consider the feedback effect of the observed communities on the geochemical fate of the resource. To do so, I combined in situ experiments and modelling with the intention to build a consistent, quantitative description of the ecogeochemical link between biodiversity and ecosystem functioning. Using leaf litter and dead wood, this approach allowed: (i) to show the importance of biotic interactions from the beginning of the community assembly process, (ii) to make the explicit connection between the resource consumption and the population dynamics of the consumers, and (iii) and to test how resource processing is affected by the specific diversity of the communities.

L’érosion interne est la cause principale de ruptures des ouvrages hydrauliques en terre, tels que les digues et les barrages. Les conséquences de telles ruptures sont conséquentes et couteuses. L’objectif de cette thèse est de mieux comprendre une catégorie particulière de processus d’érosion, la suffusion, en en caractérisant l’initiation et l’évolution. Cette recherche, à dominante expérimentale, s'appuie sur une modélisation physique unidimensionnelle. Les essais sont réalisés dans une conduite en plexiglas de 18 cm de diamètre intérieur, équipée de capteurs de pression, d’un débitmètre et d’un turbidimètre. Un dispositif de collecte des particules érodées est installé à l’aval de la conduite pour quantifier les particules érodées à des intervalles de temps choisis. Dans cette étude, on a réalisé une série d’essais sur des matériaux pulvérulents. Dans ce type de matériaux, l’érosion se manifeste par suffusion. Elle correspond à l’arrachement et au transport des particules fines à travers l’espace poral des particules grossières. Dans un premier temps, un protocole de reconstitution de matériaux pulvérulents est élaboré. Le principe consiste à réaliser des mélanges humides avec une teneur en eau relative à la masse des particules fines. Pour surmonter les problèmes rencontrés dans la réalisation des essais, la conduite est disposée verticalement, et les matériaux testés sont reconstitués à partir de mélanges de particules sableuses. Une étude paramétrique est menée sur l’influence de certains paramètres, tels que la granulométrie, la pression d’écoulement, la nature et la teneur en particules argileuses ainsi que la densité de mise en place. Les résultats obtenus montrent que l’érodabilité des matériaux dépend de la forme des courbes granulométrique. En effet, l’érosion est plus accentuée pour les matériaux contenant moins de particules fines. Elle est également plus forte quand la courbe granulométrique est discontinue. L’ajout de particules argileuses augmente la résistance à la suffusion des matériaux testés. Trois catégories de matériaux argileux ou fins sont testées : une illite (argile verte de Velay), une kaolinite (Speswhite), et du sable broyé (C10). Les résultats montrent que les matériaux contenant de l’illite sont plus résistants à la suffusion que les matériaux contenant de la kaolinite, tandis que les matériaux contenant du sable broyé sont les moins résistants. Cette résistance à la suffusion augmente avec la teneur en particules argileuses. L’érosion des matériaux dépend aussi de la densité initiale des matériaux testés. En effet, pour la même pression d’entrée, la quantité des particules érodées diminue en augmentant la densité de mise en place / Internal erosion is the main cause of failure of hydraulic structures such dykes and dams. The consequences of such failures are substantial and costly. The objective of this thesis is to better understand one of the erosion phenomena, the suffusion, and to characterize the initiation and the evolution of this phenomenon. A physical modeling approach is used for this study. Tests are carried out in a Plexiglas pipe of 18 cm inner diameter, equipped with pressure sensors, flowmeter and turbidimeter. A device for collecting the eroded particles, at selected time intervals, is installed in the downstream part of the device. In this study we performed a series of tests on coarse cohesionless soil. In this type of material, erosion is manifested by suffusion. It corresponds to the detachment and transport of fine particles through the pore space of the coarse particles. First, a cohesionless soil reconstitution protocol is developed. The idea is to make wet mixtures with water content depending on the fine particle content. To overcome some problems encountered in carrying out the tests, the device is arranged vertically, and the materials tested are reconstituted from mixtures of sand particles. A parametric study on the influence of several parameters such as particle size distribution, flow pressure, nature and content of clay particles and initial density are conducted. The results show that the erodibility of the material depends on the shape of the particle size distribution. Indeed erosion is more pronounced for materials containing less fine particles. This erodability is more pronounced when the curve is gap-graded. Erodibility of the tested soils increases with the hydraulic load. The addition of clay particles increases the resistance to suffusion of the soils. Three categories of clayed or fine soils are tested: illite (Argile Verte de Velay), kaolinite (Speswhite), and crushed sand (C10). The results show that materials containing illite are more resistant to suffusion than materials containing kaolinite, whereas materials containing crushed sand are less resistant. This resistance to suffusion increases with clay particle content. The erosion of materials also depends on the initial density of the soil tested. Indeed, for the same applied pressure, the quantity of eroded particles decreases with increasing the initial density

Sublevel caving (SLC) is a mass mining method relying on the flowability of the blasted material. The ore is blasted in slices against caved material which is mainly waste rock. The result of the confined blast is greatly influenced by the interaction between the blasted material and the caved material. During blasting both materials change characteristics; the blasted material increases its porosity and compressibility due to breakage and swelling while the caved material is compacted and decreases in porosity and compressibility. The understanding of the mechanisms involved in this process is of significant importance. The behavior of the caved material (confining material) was studied in laboratory under dynamic loading. A new apparatus was developed to conduct impact tests to simulate blasting conditions. The tested material was a blend of crushed waste rock from drift development in the Kiirunavaara mine with maximum particle size 32 mm. The material was tested for two conditions, i.e. dry and wet (pendular state), and with different impact velocities (low (5 m/s), medium (8 m/s) and high (10-12 m/s)). During the impact tests, two types of measurements were taken; dynamic measurements based on the recordings from the installed accelerometers on the machine and static measurements pre- and post-impact. Additionally, the angle of repose, the impact duration, and the fragmentation was measured. In addition to the laboratory tests, small-scale blasting tests were carried out to investigate the burden behavior in confined conditions. The blasted specimen was a cuboid magnetic mortar block and the confining material was crushed concrete with maximum particle size 16 mm. The blocks were instrumented with custom-made incremental displacement sensor. After the analysis of the results from the above experimental work, two confined pillar tests (test #1 and test #2) were carried out at the Kiirunavaara mine. The preparation work for the pillar tests involved the development of instrumentation and installation techniques. The experimental configuration contained two blastholes and measurement holes in between the blastholes drilled from the neighboring drift. Test #1 mainly focused on the evaluation of the instrumentation and techniques while test #2 was focused on the interaction between the blasted burden and the confining material. The confining material in test #1 was a blend of ore and waste material from drift development at the Kiirunavaara mine. The characteristics of the material were unknown. Test #2 was split into two parts, the confining material in the first part was the same as in the laboratory impact tests and the second part of the pillar was confined by caved masses. The instrumentation was installed in the burden of the pillars and was equipped with accelerometers and displacement sensor. Additional instrumentation was also installed in the confining material. The burden in the small-scale blasting tests reached maximum velocity 29 m/s and maximum displacement 12.6 mm. In pillar tests, the burden movement was in the range of 0.9 to 1.1 m. In both pillar tests, burden erosion material was observed in the gap between the intact and the blasted burden. This material was finer compared to the blasted burden. The origin of this material was from the vicinity of the blastholes. The results of the laboratory tests showed that the wet material exhibited larger compaction zone than that of the dry material. The wet material showed apparent cohesion close to the impact surface of the tested material. A similar observation was made in test #2 where an agglomeration of the confining material, as a result of apparent cohesion, was observed on the surface of the blasted burden. The displacement data from the instrumentation in the burden and inside the confining material showed that the compaction zone follows an inverse exponential behavior. After the blast steeper angles of repose were measured indicating higher frictional forces between the particles. Moreover, the evidence of apparent cohesion and a larger angle of repose indicated the introduction of tensile strength in the material. The mass of the confining material was compressed elastically and plastically during the blast. After the blast, the material recovered its elastic deformation and pushed the blasted burden backward as observed in the small-scale blasting tests and the pillar tests. At this stage, the burden erosion material was compacted. Hence, there were 3 materials, i.e. burden erosion material, burden and confining material, which were compacted with different compaction rates. This condition promotes interlocking of the particles in the materials. If this behavior is correlated with a production SLC ring, then it indicates disturbances in flowability of the blasted material.

Les protéines sont des molécules flexibles, qui accomplissent une variété de tâches cellulaires à travers des mouvements mécaniques et des changements conformationnels encodés dans leur structure tridimensionnelle. Parmi les approches théoriques qui contribuent à une meilleure compréhension de la relation entre structure, mécanique, dynamique et fonction des protéines, les modèles gros-grains sont un outil très puissant. Ils permettent d’intégrer des informations structurales et dynamiques à un coût computationnel réduit, car le traitement explicite des degrés de liberté moins importants est supprimé. Dans le cadre de cette thèse, des études comparatives rapides de la flexibilité et de la mécanique des protéines ont été menées en se servant du simple modèle gros-grains de Réseau Élastique. La dépendance des résultats de la conformation de départ, ainsi que une liberté dynamique de la chaine principale plutôt limitée, imposée par l’approximation harmonique, nous ont motivé à développer une nouvelle approche, permettant une exploration plus extensive de l’espace conformationnel. Les efforts ont conduit à PaLaCe, modèle gros-grains qui permet des changements majeurs de la structure secondaire, tout en gardant la spécificité de la séquence des acides aminés grâce à une représentation à basse résolution. En utilisant PaLaCe nous avons simulé deux processus impliquant la plasticité protéique: le dépliement du domaine I27 de la protéine musculaire titine et la dynamique à l’équilibre autour de la structure native de deux enzymes homologues adaptées à des températures différentes. Les résultats obtenus concordent avec les données expérimentales et les résultats issus de modèles tout-atom déjà publiés. PaLaCe s’avère donc être un modèle fiable, avec des temps de calcul restreints par rapport aux modèles tout-atome, tout en conservant un bon niveau de détail. Il offre ainsi la possibilité d’effectuer une recherche systématique sur les liens entre mécanique, dynamique et fonction des protéines / Proteins are flexible molecules, which accomplish a variety of cellular tasks through mechanical motions and conformational fluctuations encoded in their three-dimensional structure. Amongst the theoretical approaches contributing to a better understanding of the relationship between protein structure, mechanics, dynamics and function, coarse-grain models are a powerful tool. They can be used to integrate structural and dynamic information over broad time and size scales at a low computational cost, achieved by averaging out the less important degrees of freedom. In this work, fast comparative studies of protein flexibility and mechanics have been performed with the simple coarse-grain Elastic Network Model. However, the dependency of the results on the starting conformation, and the rather constrained backbone dynamics imposed by the harmonic approximation, motivated the development of a new approach, for a more extensive exploration of conformational space. These efforts led to the PaLaCe model, designed to allow significant changes in secondary structure, while maintaining residue specificity despite a lower-level resolution. Using PaLaCe, we were able to reproduce two processes involving protein plasticity: the mechanical unfolding of the I27 domain of the giant muscle protein titin and the near-native dynamics of two homologous enzymes adapted to work at different temperatures. Agreement with experimental data and results from published atomistic models demonstrate that PaLaCe is a reliable, sufficiently accurate, but computationally inexpensive approach. It therefore opens the doors for a systematic investigation of the link between protein dynamics/mechanics and function

abstract: Polyurea is a highly versatile material used in coatings and armor systems to protect against extreme conditions such as ballistic impact, cavitation erosion, and blast loading. However, the relationships between microstructurally-dependent deformation mechanisms and the mechanical properties of polyurea are not yet fully understood, especially under extreme conditions. In this work, multi-scale coarse-grained models are developed to probe molecular dynamics across the wide range of time and length scales that these fundamental deformation mechanisms operate. In the first of these models, a high-resolution coarse-grained model of polyurea is developed, where similar to united-atom models, hydrogen atoms are modeled implicitly. This model was trained using a modified iterative Boltzmann inversion method that dramatically reduces the number of iterations required. Coarse-grained simulations using this model demonstrate that multiblock systems evolve to form a more interconnected hard phase, compared to the more interrupted hard phase composed of distinct ribbon-shaped domains found in diblock systems. Next, a reactive coarse-grained model is developed to simulate the influence of the difference in time scales for step-growth polymerization and phase segregation in polyurea. Analysis of the simulated cured polyurea systems reveals that more rapid reaction rates produce a smaller diameter ligaments in the gyroidal hard phase as well as increased covalent bonding connecting the hard domain ligaments as evidenced by a larger fraction of bridging segments and larger mean radius of gyration of the copolymer chains. The effect that these processing-induced structural variations have on the mechanical properties of the polymer was tested by simulating uniaxial compression, which revealed that the higher degree of hard domain connectivity leads to a 20% increase in the flow stress. A hierarchical multiresolution framework is proposed to fully link coarse-grained molecular simulations across a broader range of time scales, in which a family of coarse-grained models are developed. The models are connected using an incremental reverse–mapping scheme allowing for long time scale dynamics simulated at a highly coarsened resolution to be passed all the way to an atomistic representation. / Dissertation/Thesis / Doctoral Dissertation Mechanical Engineering 2020

Genetic algorithms are modern algorithms intended to solve optimization problems. Inspiration originates in evolutionary principles in nature. Parallelization of genetic algorithms provides not only faster processing but also new and better solutions. Parallel genetic algorithms are also closer to real nature than their sequential counterparts. This paper describes the most used models of parallelization of genetic algorithms. Moreover, it provides the design and implementation in programming language Python. Finally, the implementation is verified in several test cases.

The diploma thesis is divided into three parts, analysis of the topic and the chosen method of solutions, application to specified building and experimental solutions and data processing The first part is theoretical. It is about air filtration in terms of normative and legal requirements and variants of technical solutions for air filtration. In the second part there are two technical solutions for HVAC systems for plastic surgery. The third part is experimental. It is the measurement of the number of particles in the air in the operating room and the evaluation of the measurement.

Die vorliegende Arbeit behandelt die Modellierung von Fließprozessen in Grundwasserleitern. Grundlage dafür ist die Grundwassergleichung, welche diese Prozesse mathematisch beschreibt. Die wichtigste hydraulische Eigenschaft von Untergründen ist hierbei die hydraulische Leitfähigkeit, welche die Fließgeschwindigkeit des Grundwassers angibt. Da man die Verteilung der Leitfähigkeit in einem betrachten Wasserleiter aber durch das Fehlen von Informationen nicht vollständig bestimmen kann, ist man auf vereinfachende Modelle und Versuchsszenarien angewiesen. In der Vergangenheit haben sich zur Untersuchung von Böden sogenannte Pumpversuche etabliert, wobei ein Brunnen gebohrt wird, welcher den Grundwasserleiter vollständig durchteuft und an dem mit konstanter Rate Wasser aus dem Boden gepumpt wird. Parallel beobachtet man an einem oder mehreren Referenzbrunnen die sich verändernde hydraulische Druckhöhe. Aus diesen Daten möchte man Informationen über den betrachteten Boden gewinnen. Dazu braucht es gewisse Modellfunktionen, welche für fest definierte Standardsituationen das Grundwasserverhalten beschreiben. Eine Möglichkeit, Böden zu klassifizieren ist es, die heterogene Struktur der Leitfähigkeit durch log-normal verteilte Zufallsgrößen zu modellieren. Dabei beschränkt man sich auf den Mittelwert, die Varianz und die Korrelationslänge dieser Verteilungen. Das hier zugrunde liegende Coarse-Graining-Modell generiert zu diesen Parametern eine effektive Leitfähigkeitsverteilung, welche nur vom radialen Abstand zum Pumpbrunnen abhängt. Damit wird die Grundwassergleichung zu einer radialsymmetrischen parabolischen Differentialgleichung. Zu dieser Differentialgleichung wurde in der vorliegenden Arbeit ein Lösungsalgorithmus entwickelt und implementiert sowie anschließend gegen verschiedene Parametereingaben getestet.

Protein-protein interaction dominates all major biology processes in living cells. Recent studies suggestthat the surface expression and activity of G protein-coupled receptors (GPCRs), which are the largestfamily of receptors in human cells, can be modulated by receptor activity–modifying proteins (RAMPs). Computational tools are essential to complement experimental approaches for the understanding ofmolecular activity of living cells and molecular dynamics simulations are well suited to providemolecular details of proteins function and structure. The classical atom-level molecular modeling ofbiological systems is limited to small systems and short time scales. Therefore, its application iscomplicated for systems such as protein-protein interaction in cell-surface membrane. For this reason, coarse-grained (CG) models have become widely used and they represent an importantstep in the study of large biomolecular systems. CG models are computationally more effective becausethey simplify the complexity of the protein structure allowing simulations to have longer timescales. The aim of this degree project was to determine if the applications of coarse-grained molecularsimulations were suitable for the understanding of the dynamics and structural basis of the GPCRRAMP interactions in a membrane environment. Results indicate that the study of protein-proteininteractions using CG needs further improvement with a more accurate parameterization that will allowthe study of complex systems.