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Kulich, Martin. "Dynamic Template Adjustment in Continuous Keystroke Dynamics." Master's thesis, Vysoké učení technické v Brně. Fakulta informačních technologií, 2015. http://www.nusl.cz/ntk/nusl-234927.
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Dynamika úhozů kláves je jednou z behaviorálních biometrických charakteristik, kterou je možné použít pro průběžnou autentizaci uživatelů. Vzhledem k tomu, že styl psaní na klávesnici se v čase mění, je potřeba rovněž upravovat biometrickou šablonu. Tímto problémem se dosud, alespoň pokud je autorovi známo, žádná studie nezabývala. Tato diplomová práce se pokouší tuto mezeru zaplnit. S pomocí dat o časování úhozů od 22 dobrovolníků bylo otestováno několik technik klasifikace, zda je možné je upravit na online klasifikátory, zdokonalující se bez učitele. Výrazné zlepšení v rozpoznání útočníka bylo zaznamenáno u jednotřídového statistického klasifikátoru založeného na normované Euklidovské vzdálenosti, v průměru o 23,7 % proti původní verzi bez adaptace, zlepšení však bylo pozorováno u všech testovacích sad. Změna míry rozpoznání správného uživatele se oproti tomu různila, avšak stále zůstávala na přijatelných hodnotách.
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Munz, Marton. "Computational studies of protein dynamics and dynamic similarity." Thesis, University of Oxford, 2012. http://ora.ox.ac.uk/objects/uuid:2fb76765-3e43-409b-aad3-b5202f4668b3.
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At the time of writing this thesis, the complete genomes of more than 180 organisms have been sequenced and more than 80000 biological macromolecular structures are available in the Protein Data Bank (PDB). While the number of sequenced genomes and solved three-dimensional structures are rapidly increasing, the functional annotation of protein sequences and structures is a much slower process, mostly because the experimental de-termination of protein function is expensive and time-consuming. A major class of in silico methods used for protein function prediction aim to transfer annotations between proteins based on sequence or structural similarities. These approaches rely on the assumption that homologous proteins of similar primary sequences and three-dimensional structures also have similar functions. While in most cases this assumption appears to be valid, an increasing number of examples show that proteins of highly similar sequences and/or structures can have different biochemical functions. Thus the relationship between the divergence of protein sequence, structure and function is more complex than previously anticipated. On the other hand, there is mounting evidence suggesting that minor changes of the sequences and structures of proteins can cause large differences in their conformational dynamics. As the intrinsic fluctuations of many proteins are key to their biochemical functions, the fact that very similar (almost identical) sequences or structures can have entirely different dynamics might be important for understanding the link between sequence, structure and function. In other words, the dynamic similarity of proteins could often serve as a better indicator of functional similarity than the similarity of their sequences or structures alone. Currently, little is known about how proteins are distributed in the 'dynamics space' and how protein motions depend on structure and sequence. These problems are relevant in the field of protein design, studying protein evolution and to better understand the functional differences of proteins. To address these questions, one needs a precise definition of dynamic similarity, which is not trivial given the complexity of protein motions. This thesis is intended to explore the possibilities of describing the similarity of proteins in the 'dynamics space'. To this end, novel methods of characterizing and comparing protein motions based on molecular dynamics simulation data were introduced. The generally applicable approach was tested on the family of PDZ domains; these small protein-protein interaction domains play key roles in many signalling pathways. The methodology was successfully used to characterize the dynamic dissimilarities of PDZ domains and helped to explain differences of their functional properties (e.g. binding promiscuity) also relevant for drug design studies. The software tools developed to implement the analysis are also introduced in the thesis. Finally, a network analysis study is presented to reveal dynamics-mediated intramolecular signalling pathways in an allosteric PDZ domain.
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Demiray, Turhan Hilmi. "Simulation of power system dynamics using dynamic phasor models /." Zürich : ETH, 2008. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=17607.
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Durazzo, Gerardo. "Simulation of supply chains dynamics using fluid-dynamic models." Doctoral thesis, Universita degli studi di Salerno, 2013. http://hdl.handle.net/10556/887.
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2011 - 2012The aim of thesis is to present some macroscopic models for supply chains and networks able to reproduce the goods dynamics, successively to show, via simulations, some phenomena appearing in planning and managing such systems and, finally, to dead with optimization problems... [edited by author]
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Hadraba, Petr. "Kmitání strojů v průmyslové praxi." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2017. http://www.nusl.cz/ntk/nusl-318140.
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The vibration analysis of a production machine is a key factor of its functionality, service life and occupational safety. This work deals with mathematical dynamic modelling and its contribution to the improvement of a mechanical design and mechanism failure prevention. The whole process is presented on the example of a drum cam rotary indexing table and on the example of actuators of multi spindle automatic lathes. The analysis consisted of complex nonlinear models based on basic linear models. It was computed using Matlab, Simulink and MSC ADAMS. Models of these mechanisms were validated with experimental measurements. The results were used for mechanical design improvement and for speed control optimization.
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Van, Wychen Wesley. "The Dynamics and Dynamic Discharge of the Ice Masses and Tidewater Glaciers of the Canadian High Arctic." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/33180.
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Speckle tracking of synthetic aperture RADAR imagery (Radarsat-1/2, ALOS PALSAR) and feature tracking of optical (Landsat-7 ETM+) imagery is used to determine the entire surface velocity structure of the major ice masses of the Canadian High Arctic in 2000, 2010-2015 and for select tidewater terminating glaciers from 1999-2010. At the termini of tidewater glaciers, surface ice velocities are combined with measured/modelled ice thicknesses to derive an estimate of mass loss via dynamic (iceberg) discharge. The total dynamic discharge for the ice masses of the southern Canadian Arctic Archipelago (SCAA: Baffin and Bylot Islands) is between ~17 and 180 Mt a-1 (0.017 to 0.180 Gt a-1) for the period 2007-2011, compared to a dynamic discharge of ~2.47 ± 0.88 Gt a-1 for the northern Canadian Arctic Archipelago (NCAA: Devon, Ellesmere, Axel Heiberg Islands) for the period 2011-2015. A comparison of these values with rates of mass loss via climatic mass balance (surface melt and runoff) indicates that dynamic discharge accounted for ~3.1% of total ablation for the NCAA in 2012 and ~0.11% of total ablation in the SCAA between 2007 and 2010. This reveals that total ablation in the Canadian Arctic is currently dominated by surface melt and runoff.
The glacier velocity dataset provides the most comprehensive record of ice motion and dynamic discharge in the Canadian Arctic to date and reveals a large degree of variability in glacier motion within the region over the last ~15 years. Most of the major glaciers in the NCAA have decelerated and their resultant dynamic discharge has decreased over the observation period, which is largely attributed to cyclical phases attributed to surging and pulsing. On pulse-type glaciers, variation in ice motion is largely confined to regions where the bed is located below sea level. A notable departure from the overall trend of regional velocity slowdown is the widespread acceleration of the Trinity and Wykeham Glaciers of the Prince of Wales Icefield (the largest glacier complex in the Canadian Arctic), which cannot be explained by surge or pulse mechanisms. The increased discharge from these two glaciers nearly compensates (within error) for the decrease in iceberg discharge from other glaciers across the study region and indicates that total dynamic discharge from the Canadian Arctic can be sensitive to the variations of ice flow of just a few glaciers.
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Fujiwara, Naoya. "Dynamic phase transition and pattern dynamics in periodic external fields." 京都大学 (Kyoto University), 2007. http://hdl.handle.net/2433/135964.
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Chen, C. C. "Imaging the spatial-temporal neuronal dynamics using dynamic causal modelling." Thesis, University College London (University of London), 2009. http://discovery.ucl.ac.uk/18517/.
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Oscillatory brain activity is a ubiquitous feature of neuronal dynamics and the synchronous discharge of neurons is believed to facilitate integration both within functionally segregated brain areas and between areas engaged by the same task. There is growing interest in investigating the neural oscillatory networks in vivo. The aims of this thesis are to (1) develop an advanced method, Dynamic Causal Modelling for Induced Responses (DCM for IR), for modelling the brain network functions and (2) apply it to exploit the nonlinear coupling in the motor system during hand grips and the functional asymmetries during face perception. DCM for IR models the time-varying power over a range of frequencies of coupled electromagnetic sources. The model parameters encode coupling strength among areas and allows the differentiations between linear (within frequency) and nonlinear (between-frequency) coupling. I applied DCM for IR to show that, during hand grips, the nonlinear interactions among neuronal sources in motor system are essential while intrinsic coupling (within source) is very likely to be linear. Furthermore, the normal aging process alters both the network architecture and the frequency contents in the motor network. I then use the bilinear form of DCM for IR to model the experimental manipulations as the modulatory effects. I use MEG data to demonstrate functional asymmetries between forward and backward connections during face perception: Specifically, high (gamma) frequencies in higher cortical areas suppressed low (alpha) frequencies in lower areas. This finding provides direct evidence for functional asymmetries that is consistent with anatomical and physiological evidence from animal studies. Lastly, I generalize the bilinear form of DCM for IR to dissociate the induced responses from evoked ones in terms of their functional role. The backward modulatory effect is expressed as induced, but not evoked responses.
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Da, Ronch Andrea. "On the calculation of dynamic derivatives using computational fluid dynamics." Thesis, University of Liverpool, 2012. http://livrepository.liverpool.ac.uk/5513/.
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In this thesis, the exploitation of computational fluid dynamics (CFD) methods for the flight dynamics of manoeuvring aircraft is investigated. It is demonstrated that CFD can now be used in a reasonably routine fashion to generate stability and control databases. Different strategies to create CFD-derived simulation models across the flight envelope are explored, ranging from combined low-fidelity/high-fidelity methods to reduced-order modelling. For the representation of the unsteady aerodynamic loads, a model based on aerodynamic derivatives is considered. Static contributions are obtained from steady-state CFD calculations in a routine manner. To more fully account for the aircraft motion, dynamic derivatives are used to update the steady-state predictions with additional contributions. These terms are extracted from small-amplitude oscillatory tests. The numerical simulation of the flow around a moving airframe for the prediction of dynamic derivatives is a computationally expensive task. Results presented are in good agreement with available experimental data for complex geometries. A generic fighter configuration and a transonic cruiser wind tunnel model are the test cases. In the presence of aerodynamic non-linearities, dynamic derivatives exhibit significant dependency on flow and motion parameters, which cannot be reconciled with the model formulation. An approach to evaluate the sensitivity of the non-linear flight simulation model to variations in dynamic derivatives is described. The use of reduced models, based on the manipulation of the full-order model to reduce the cost of calculations, is discussed for the fast prediction of dynamic derivatives. A linearized solution of the unsteady problem, with an attendant loss of generality, is inadequate for studies of flight dynamics because the aircraft may experience large excursions from the reference point. The harmonic balance technique, which approximates the flow solution in a Fourier series sense, retains a more general validity. The model truncation, resolving only a small subset of frequencies typically restricted to include one Fourier mode at the frequency at which dynamic derivatives are desired, provides accurate predictions over a range of two- and three-dimensional test cases. While retaining the high fidelity of the full-order model, the cost of calculations is a fraction of the cost for solving the original unsteady problem. An important consideration is the limitation of the conventional model based on aerodynamic derivatives when applied to conditions of practical interest (transonic speeds and high angles of attack). There is a definite need for models with more realism to be used in flight dynamics. To address this demand, various reduced models based on system-identification methods are investigated for a model case. A non-linear model based on aerodynamic derivatives, a multi-input discrete-time Volterra model, a surrogate-based recurrence-framework model, linear indicial functions and radial basis functions trained with neural networks are evaluated. For the flow conditions considered, predictions based on the conventional model are the least accurate. While requiring similar computational resources, improved predictions are achieved using the alternative models investigated. Furthermore, an approach for the automatic generation of aerodynamic tables using CFD is described. To efficiently reduce the number of high-fidelity (physics-based) analyses required, a kriging-based surrogate model is used. The framework is applied to a variety of test cases, and it is illustrated that the approach proposed can handle changes in aircraft geometry. The aerodynamic tables can also be used in real-time to fly the aircraft through the database. This is representative of the role played by CFD simulations and the potential impact that high-fidelity analyses might have to reduce overall costs and design cycle time.
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Karlsson, Stefan, and Erik Hansson. "Dynamic Load Generator: Synthesising dynamic hardware load characteristics." Thesis, Mälardalens högskola, Inbyggda system, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-28280.
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In this thesis we proposed and tested a new method for creating synthetic workloads. Our method takes the dynamic behaviour into consideration, whereas previous studies only consider the static behaviour. This was done by recording performance monitor counters (PMC) events from a reference application. These events were then used to calculate the hardware load characteristics, in our case cache miss ratios, that were stored for each sample and used as input to a load regulator. A signalling application was then used together with a load regulator and a cache miss generator to tune the hardware characteristics until they were similar to those of the reference application. For each sample, the final parameters from the load regulator were stored in order to be able to simulate it. By simulating all samples with the same sampling period with which they were recorded, the dynamic behaviour of the reference application could be simulated. Measurements show that this was successful for L1 D$ miss ratio, but not for L1 I$ miss ratio and only to a small extent for L2 D$ miss ratio. We were also able to show that the total convergence time for the regulator could be reduced by using case-based reasoning to select the initial parameters from similar samples.
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Štencl, Michal. "Bezpečnostní parkovací brzdy pro servomotory." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2017. http://www.nusl.cz/ntk/nusl-318158.
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This Master thesis is focused on electromagnetic brakes for servomotors. In the first chapter is described principle of operation, later then design and main parameters are explained. The main part of thesis is focused on calculation of dynamic parameters of electromagnetic brakes. Calculations are solved first by analytic method in Matlab–Simulink, then by finite element analysis. Results are compared with measurements on prototype brake.
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Ibarra, Roca Ricardo, and la Iglesia Couto Pablo de. "Dynamic Websites." Thesis, Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE), 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-887.
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Monticini, Andrea. "Dynamic economics." Thesis, University of Exeter, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.535908.
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Tugwell, David. "Dynamic syntax." Thesis, University of Edinburgh, 1999. http://hdl.handle.net/1842/22703.
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This thesis presents a model of natural language syntax as a dynamic system, defining possible transitions between a set of states. The model is inherently left-to-right in nature, with the states representing the growing interpretation of a sentence, and syntactic rules specifying the way the interpretation can be incremented given the next word in the string. In the first part of the thesis, I address the question of the use of models in linguistics. Accepting the standard arguments for the modularity of the process of language comprehension, I argue nevertheless that a model of syntactic competence is only open to objective evaluation if it is embedded in an overall model of performance. I argue that a dynamic formulation of the competence grammar ensures a transparent relation to what is known about language comprehension, in particular its incremental nature. I show that this obviates the need for a level of independent syntactic structure (either constituent or dependency-based), and is thus maximally parsimonious. In the proposed model, syntactic rules do not form an autonomous system, but make direct reference to the growing interpretation, thus distinguishing the model from other incremental approaches. In the second part, I go on to examine a wide-range of syntactic constructions, predominantly in English, and discuss how they may be modelled in the dynamic system. This includes a range of unbounded dependency constructions, problems of complement control, coordination and syntactic constraints on the binding of anaphora. In the final part, I look at the issues involved in embedding the dynamic model of syntactic competence in a model of language comprehension, seen both as a practical tool and as a model of the human sentence processor. I discuss how a probabilistic language model may be created by training the model of syntax on pre-analyzed data. Finally, I consider the consequences of possible processing strategies and how to model limitations on the human processor.
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Chambers, Steven B. "Investigation of combustive flows and dynamic meshing in computational fluid dynamics." Thesis, Texas A&M University, 2004. http://hdl.handle.net/1969.1/1324.
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Computational Fluid Dynamics (CFD) is a field that is constantly advancing. Its advances in terms of capabilities are a result of new theories, faster computers, and new numerical methods. In this thesis, advances in the computational fluid dynamic modeling of moving bodies and combustive flows are investigated. Thus, the basic theory behind CFD is being extended to solve a new class of problems that are generally more complex. The first chapter that investigates some of the results, chapter IV, discusses a technique developed to model unsteady aerodynamics with moving boundaries such as flapping winged flight. This will include mesh deformation and fluid dynamics theory needed to solve such a complex system. Chapter V will examine the numerical modeling of a combustive flow. A three dimensional single vane burner combustion chamber is numerically modeled. Species balance equations along with rates of reactions are introduced when modeling combustive flows and these expressions are discussed. A reaction mechanism is validated for use with in situ reheat simulations. Chapter VI compares numerical results with a laminar methane flame experiment to further investigate the capabilities of CFD to simulate a combustive flow. A new method of examining a combustive flow is introduced by looking at the solutions ability to satisfy the second law of thermodynamics. All laminar flame simulations are found to be in violation of the entropy inequality.
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Kachani, Soulaymane, and Georgia Perakis. "Modeling Travel Times in Dynamic Transportation Networks; A Fluid Dynamics Approach." Massachusetts Institute of Technology, Operations Research Center, 2001. http://hdl.handle.net/1721.1/5224.
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In this paper, we take a fluid dynamics approach to determine the travel time in traversing a network's link. We propose a general model for travel time functions that utilizes fluid dynamics laws for compressible flow to capture a variety of flow patterns such as the formation and dissipation of queues, drivers' response to upstream congestion or decongestion and drivers' reaction time. We examine two variants of the model, in the case of separable velocity functions, which gives rise to two families of travel time functions for the problem; a polynomial and an exponential family. We analyze these travel time functions and examine several special cases. Our investigation also extends to the case of non-separable velocity functions starting with an analysis of the interaction between two links, and then extending it to the general case of acyclic networks.
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Gaddoni, Giacomo. "Modeling of Evolutionary Cancer Dynamics and Optimal Treatment via Dynamic Programming." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021.
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Cancer is one of the biggest challenges in healthcare. Fast diagnosis and personalized pharmacological therapies are essential for lowering the mortality rate. In this thesis, we propose a general-purpose model for cancer and an optimal control strategy to minimize its volume. Firstly, we analyze the literature about cancer in the System and Control community and produce a taxonomy of cancer typologies. We identify four main behaviors arising in these models: growth, mutation, migration, and drug response. After this preliminary analysis, we propose a cancer treatment model based on Ordinary Differential Equations (ODEs) and Evolutionary Game Theory, that captures these dynamics more generally. ODEs provide a framework for lumped-parameters representations, and Evolutionary Game Theory provides tools to describe competitive behaviors typical of these cell populations. Starting from this taxonomy, we chose a model representable with a 2-node graph that expressed all the dynamics of cancer processes. We studied the model, discretized it, and applied an optimal control method based on Differential Dynamic Programming (DDP). Bounded and unbounded DDP were ineffective. It was necessary to introduce regularized DDP via adaptive shift. With this algorithm, the results are promising: the system is successfully stabilized in the origin. It is also possible to control the system, driving it between two equilibria, tracking a demanded trajectory. Most of the testing was done in MATLAB. Then, the project was ported to Python. This was done to facilitate future expansion of the model and control strategies through scientific analysis toolboxes and frameworks.
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Lee, SeeWoo. "Development of new dynamic tire model for improved vehicle dynamics simulation." The Ohio State University, 1994. http://rave.ohiolink.edu/etdc/view?acc_num=osu1334584006.
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Abbs, Brandon Robert. "The temporal dynamics of auditory memory for static and dynamic sounds." Diss., University of Iowa, 2008. http://ir.uiowa.edu/etd/4.
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Rupp, Matthew Y. "Passive dynamic steering system model for use in vehicle dynamics simulation." Connect to resource, 1994. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1157568618.
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Currier, Patrick Norman. "A Method for Modeling and Prediction of Ground Vehicle Dynamics and Stability in Autonomous Systems." Diss., Virginia Tech, 2011. http://hdl.handle.net/10919/27632.
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A future limitation of autonomous ground vehicle technology is the inability of current algorithmic techniques to successfully predict the allowable dynamic operating ranges of unmanned ground vehicles. A further difficulty presented by real vehicles is that the payloads may and probably will change with unpredictably time as will the terrain on which it is expected to operate. To address this limitation, a methodology has been developed to generate real-time estimations of a vehicleâ s instantaneous Maneuvering Manifold. This approach uses force-moment method techniques to create an adaptive, parameterized vehicle model. A technique is developed for estimation of vehicle load state using internal sensors combined with low-magnitude maneuvers. An unscented Kalman filter based estimator is then used to estimate tire forces for use in determining the ground/tire coefficient of friction. Probabilistic techniques are then combined with a combined-slip pneumatic trail based estimator to estimate the coefficient of friction in real-time. This data is then combined to map out the instantaneous maneuvering manifold while applying techniques to account for dynamic rollover and stability limitations. The algorithms are implemented in MATLAB, simulated against TruckSim models, and results are shown to demonstrate the validity of the techniques. The developed methodology is shown to be a novel approach that is capable of addressing the problem of successfully estimating the available maneuvering manifold for autonomous ground vehicles.Ph. D.
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Hughes, Jonathan L. "Applications of Stability Analysis to Nonlinear Discrete Dynamical Systems Modeling Interactions." VCU Scholars Compass, 2015. http://scholarscompass.vcu.edu/etd/3819.
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Many of the phenomena studied in the natural and social sciences are governed by processes which are discrete and nonlinear in nature, while the most highly developed and commonly used mathematical models are linear and continuous. There are significant differences between the discrete and the continuous, the nonlinear and the linear cases, and the development of mathematical models which exhibit the discrete, nonlinear properties occurring in nature and society is critical to future scientific progress. This thesis presents the basic theory of discrete dynamical systems and stability analysis and explores several applications of this theory to nonlinear systems which model interactions involving economic agents and biological populations. In particular we will explore the stability properties of equilibria associated with inter-species and intergenerational population dynamics in biology and market price and agent composition dynamics in economics.
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Aktan, Mikael. "Dynamic hair effects." Thesis, University of Gävle, Department of Mathematics, Natural and Computer Sciences, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-187.
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Creating three dimensional hair is still one of the hardest elements when creating characters. Problems occur because of the constant changes in the software every few years. A major goal is to create as realistic hair as possible in Autodesk Maya and to supply this detailed information on to other 3D artist. Techniques are researched and reviewed on how different hair systems are created, as well as how dynamic effects react on the moving hair.
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Bohm, Igor. "Speeding up dynamic compilation : concurrent and parallel dynamic compilation." Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/6694.
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The main challenge faced by a dynamic compilation system is to detect and translate frequently executed program regions into highly efficient native code as fast as possible. To efficiently reduce dynamic compilation latency, a dynamic compilation system must improve its workload throughput, i.e. compile more application hotspots per time. As time for dynamic compilation adds to the overall execution time, the dynamic compiler is often decoupled and operates in a separate thread independent from the main execution loop to reduce the overhead of dynamic compilation. This thesis proposes innovative techniques aimed at effectively speeding up dynamic compilation. The first contribution is a generalised region recording scheme optimised for program representations that require dynamic code discovery (e.g. binary program representations). The second contribution reduces dynamic compilation cost by incrementally compiling several hot regions in a concurrent and parallel task farm. Altogether the combination of generalised light-weight code discovery, large translation units, dynamic work scheduling, and concurrent and parallel dynamic compilation ensures timely and efficient processing of compilation workloads. Compared to state-of-the-art dynamic compilation approaches, speedups of up to 2.08 are demonstrated for industry standard benchmarks such as BioPerf, Spec Cpu 2006, and Eembc. Next, innovative applications of the proposed dynamic compilation scheme to speed up architectural and micro-architectural performance modelling are demonstrated. The main contribution in this context is to exploit runtime information to dynamically generate optimised code that accurately models architectural and micro-architectural components. Consequently, compilation units are larger and more complex resulting in increased compilation latencies. Large and complex compilation units present an ideal use case for our concurrent and parallel dynamic compilation infrastructure. We demonstrate that our novel micro-architectural performance modelling is faster than state-of-the-art Fpga-based simulation, whilst providing the same level of accuracy.
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Chapman, Craig K. "Coarsening dynamical systems : dynamic scaling, universality and mean-field theories." Thesis, University of Glasgow, 2012. http://theses.gla.ac.uk/3255/.
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We study three distinct coarsening dynamical systems (CDS) and probe the underlying scaling laws and universal scaling functions. We employ a variety of computational methods to discover and analyse these intrinsic statistical objects. We consider mean-field type models, similar in nature to those used in the seminal work of Lifshitz, Slyozov and Wagner (LSW theory), and statistical information is then derived from these models. We first consider a simple particle model where each particle possesses a continuous positive parameter, called mass, which itself determines the particle’s velocity through a prescribed law of motion. The varying speeds of particles, caused by their differing masses, causes collisions to take place, in which the colliding particles then merge into a single particle while conserving mass. We computationally discover the presence of scaling laws of the characteristic scale (mean mass) and universal scaling functions for the distribution of particle mass for a family of power-law motion rules. We show that in the limit as the power-law exponent approaches infinity, this family of models approaches a probabilistic min-driven model. This min-driven model is then analysed through a mean-field type model, which yields a prediction of the universal scaling function. We also consider the conserved Kuramoto-Sivashinsky (CKS) equation and provide, in particular, a critique of the effective dynamics derived by Politi and ben-Avraham. We consider several different numerical methods for solving the CKS equation, both on fixed and adaptive grids, before settling on an implicit-explicit hybrid scheme. We then show, through a series of detailed numerical simulations of both the CKS equation and the proposed dynamics, that their particular reduction to a length-based CDS does not capture the effective dynamics of the CKS equation. Finally, we consider a faceted CDS derived from a one-dimensional geometric partial differential equation. Unusually, an obvious one-point mean-field theory for this CDS is not present. As a result, we consider the two-point distribution of facet lengths. We derive a mean-field evolution equation governing the two-point distribution, which serves as a two-dimensional generalisation of the LSW theory. Through consideration of the two-point theory, we subsequently derive a non-trivial one-point sub-model which we analytically solve. Our predicted one-point distribution bears a significant resemblance to the LSW distribution and stands in reasonable agreement with the underlying faceted CDS.
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Epiphaniou, Nicholas. "Modelling of Dynamic Friction Across Solid Material Interfaces Using Molecular Dynamics Techniques." Thesis, Cranfield University, 2009. http://hdl.handle.net/1826/4458.
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The topic of this PhD is to investigate materials interfaces under the application of com-pressive forces and dynamic friction. Friction studies are important in applications for high-speed machining and ballistic penetration modelling, two areas where it is important to understand the behaviour of rapidly moving interfaces. Gaining insight into the velocity dependence of the effective tangential force, and its time-evolution, under various external loads is also of particular interest. It is important to understand on an atomic and/or molec-ular level the fundamentals of tribological processes. Some of the processes investigated in this thesis include plastic deformation due to high compression, the response of materials when sliding occurs in terms of temperature variation across the interface and its relation-ship with atomic diffusion. Moreover, the materials dependence on operating conditions of temperature, loading and dynamic friction are factors that ultimately determine the design of tribological systems.
In the last few years it has been shown that materials properties depend on the size, as smaller specimens are relatively stronger than larger ones. This thesis is aiming to em-ploy state of the art numerical and theoretical methods, which are vital to give a significant insight and understanding of the fundamental issues concerning dynamic friction of tribo-logical processes at the atomic scale. The mechanical behaviour is investigated in detail to reveal an accurate theoretical description of the frictional force at metallic surfaces. Special consideration is taken into account for the mechanism that causes dissipation in the form of heat. The strong deformation when materials undergo dynamic friction causes energy to dissipate away from the interface at a high rate.
Additionally, investigation of the plastic deformation and its variation under conditions prevalent at high speed sliding is carried out. Knowledge of the yield point under these conditions is important to obtain accurate constitutive models for the shear stresses. In-vestigating how the material strength varies under sliding friction and obtaining accurate evaluation of the stresses involved has proved difficult and time consuming. This is primar¬ily attributed to the fact that experiments are difficult to conduct and expensive facilities are required. This thesis focuses on aspects of this complex process with the aid of molecular dynamic simulations.
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Bradford, Robert D. "Solving dynamic battlespace movement problems using dynamic distributed computer networks /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA380802.
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Bradford, Robert D. III. "Solving dynamic battlespace movement problems using dynamic distributed computer networks." Thesis, Monterey, California. Naval Postgraduate School, 2000. http://hdl.handle.net/10945/7794.
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Approved for public release, distribution is unlimitedThis thesis develops an architecture for dynamic distributed military operations research. This architecture assumes that a network of heterogeneous computing devices connects forces throughout the battlespace. Both the raw data about the battlespace and the operations research models used to analyze this data are accessible to devices on this network. The thesis designs a system using this architecture that invokes operations research network optimization algorithms to solve problems involving movement of people and equipment over dynamic road networks. A specific application is, implemented to help a medic find the nearest aid station using a shortest path algorithm. This application marshals the most current data on unit locations and road conditions (distributed across the computing network) and locates on the network an appropriate algorithm that is then used to construct a solution. The answer is returned to the user as a web page in a form appropriate for his computing device. The application is implemented with existing technologies including the Java computer language, Konig, a Java-based tool for representing networks and graphs, and Hypertext Markup Language, a format for shared information on the Internet. This system uses operations research tools to transform data into decisions in real-time or near real-time.
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Periorellis, Panayiotis. "Dynamic enterprise modelling : a methodology for animating dynamic social networks." Thesis, University of Newcastle Upon Tyne, 2000. http://hdl.handle.net/10443/2134.
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Since the introduction of the Internet and the realisation of its potential companies have either transformed their operation or are in the process of doing so. It has been observed, that developments in I.T., telecommunications and the Internet have boosted the number of enterprises engaging into e-commerce, e-business and virtual enterprising. These trends are accompanied by re-shaping, transformation and changes in an enterprise's boundaries. The thesis gives an account of the research into the area of dynamic enterprise modelling and provides a modelling methodology that allows different roles and business models to be tested and evaluated without the risk associated with committing to a change.
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Kleingartner, Justin Alan. "Dynamic wetting of soft materials and applications of dynamic tensiometry." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/101508.
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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Chemical Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 171-184).
Surfaces and interfaces pervade our world and understanding the phenomena that occur at them is imperative for a wide range of commercial and industrial applications. This thesis focuses on investigating the influence of physical and chemical parameters on surface wettability and characterizing interfacial phenomena in a range of solid-liquid systems. In particular, a surface characterization technique (dynamic tensiometry) has been extended to provide further insight into the wetting properties of liquid-repellent surfaces, and the efficacy of engineered surfaces for applications in drag reduction, oleophobic fabric design and fog harvesting is detailed. Goniometric techniques traditionally quantify two parameters, the advancing and receding contact angles, that are useful for characterizing the wetting properties of a solid surface; however, dynamic tensiometry can provide further insight into the wetting properties of a surface. A framework for analyzing tensiometric results will be detailed that allows for the determination of wetting hysteresis, wetting state transitions, and characteristic topographical length scales on textured, nonwetting surfaces, in addition to the more traditional measurement of apparent advancing and receding contact angles. Switchable polymer multilayer coatings were prepared that reversibly and repeatedly rearrange from hydrophobic to hydrophilic (or vice versa) when contacted with water (or air). By examining the time evolution of the water contact angle at various temperatures, the apparent activation energy for the forward surface rearrangement (Ea,f) can be determined. Further insight can be gained into the kinetics of this surface reconstruction process by utilizing dynamic tensiometry to measure the evolution in the contact angle of a liquid meniscus at several rates and temperatures as it advances or recedes over the multilayer films. Next, the efficacy of engineered surfaces for three applications is explored. First, the ability of a superhydrophobic surface to reduce skin friction in turbulent Taylor-Couette flow is investigated. A reduction in the wall shear stress measured at the rotating inner cylinder is demonstrated by depositing sprayable superhydrophobic microstructures on the inner rotor surface. The magnitude of skin friction reduction becomes progressively larger as Re increases with a decrease of 22% observed at Re = 80, 000. I next detail a framework for designing robust hierarchically textured oleophobic fabrics. The liquid repellency of woven and nano-textured oleophobic fabrics is analyzed using a nested model with n levels of hierarchy that is constructed from modular units of cylindrical and spherical building blocks. For a plain-woven mesh comprised of chemically treated fiber bundles (n = 2), the tight packing of individual fibers in each bundle imposes a geometric constraint on the maximum oleophobicity that can be achieved solely by modifying the surface energy of the coating. I demonstrate how the introduction of an additional higher order micro /nano-texture on the fibers (n = 3) is necessary to overcome this limit and create more robustly non-wetting fabrics. Finally, previous work on fog harvesting is expanded at both the lab and pilot scales. The methodology for coating lab scale meshes is scaled up, allowing standard fog collectors (SFCs) to be coated, which are currently being deployed in the field for real world testing. Furthermore, a lab scale fog harvesting apparatus is used to investigate how mesh wire geometry affects the prevalence of mesh clogging and observe that thin rectangular wires show promise in reducing the effect of clogging for a given fog mesh spacing.
by Justin Alan Kleingartner.
Ph. D.
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Corneli, Marco. "Dynamic stochastic block models, clustering and segmentation in dynamic graphs." Thesis, Paris 1, 2017. http://www.theses.fr/2017PA01E012/document.
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Cette thèse porte sur l’analyse de graphes dynamiques, définis en temps discret ou continu. Nous introduisons une nouvelle extension dynamique du modèle a blocs stochastiques (SBM), appelée dSBM, qui utilise des processus de Poisson non homogènes pour modéliser les interactions parmi les paires de nœuds d’un graphe dynamique. Les fonctions d’intensité des processus ne dépendent que des classes des nœuds comme dans SBM. De plus, ces fonctions d’intensité ont des propriétés de régularité sur des intervalles temporels qui sont à estimer, et à l’intérieur desquels les processus de Poisson redeviennent homogènes. Un récent algorithme d’estimation pour SBM, qui repose sur la maximisation d’un critère exact (ICL exacte) est ici adopté pour estimer les paramètres de dSBM et sélectionner simultanément le modèle optimal. Ensuite, un algorithme exact pour la détection de rupture dans les séries temporelles, la méthode «pruned exact linear time» (PELT), est étendu pour faire de la détection de rupture dans des données de graphe dynamique selon le modèle dSBM. Enfin, le modèle dSBM est étendu ultérieurement pour faire de l’analyse de réseau textuel dynamique. Les réseaux sociaux sont un exemple de réseaux textuels: les acteurs s’échangent des documents (posts, tweets, etc.) dont le contenu textuel peut être utilisé pour faire de la classification et détecter la structure temporelle du graphe dynamique. Le modèle que nous introduisons est appelé «dynamic stochastic topic block model» (dSTBM)This thesis focuses on the statistical analysis of dynamic graphs, both defined in discrete or continuous time. We introduce a new extension of the stochastic block model (SBM) for dynamic graphs. The proposed approach, called dSBM, adopts non homogeneous Poisson processes to model the interaction times between pairs of nodes in dynamic graphs, either in discrete or continuous time. The intensity functions of the processes only depend on the node clusters, in a block modelling perspective. Moreover, all the intensity functions share some regularity properties on hidden time intervals that need to be estimated. A recent estimation algorithm for SBM, based on the greedy maximization of an exact criterion (exact ICL) is adopted for inference and model selection in dSBM. Moreover, an exact algorithm for change point detection in time series, the "pruned exact linear time" (PELT) method is extended to deal with dynamic graph data modelled via dSBM. The approach we propose can be used for change point analysis in graph data. Finally, a further extension of dSBM is developed to analyse dynamic net- works with textual edges (like social networks, for instance). In this context, the graph edges are associated with documents exchanged between the corresponding vertices. The textual content of the documents can provide additional information about the dynamic graph topological structure. The new model we propose is called "dynamic stochastic topic block model" (dSTBM).Graphs are mathematical structures very suitable to model interactions between objects or actors of interest. Several real networks such as communication networks, financial transaction networks, mobile telephone networks and social networks (Facebook, Linkedin, etc.) can be modelled via graphs. When observing a network, the time variable comes into play in two different ways: we can study the time dates at which the interactions occur and/or the interaction time spans. This thesis only focuses on the first time dimension and each interaction is assumed to be instantaneous, for simplicity. Hence, the network evolution is given by the interaction time dates only. In this framework, graphs can be used in two different ways to model networks. Discrete time […] Continuous time […]. In this thesis both these perspectives are adopted, alternatively. We consider new unsupervised methods to cluster the vertices of a graph into groups of homogeneous connection profiles. In this manuscript, the node groups are assumed to be time invariant to avoid possible identifiability issues. Moreover, the approaches that we propose aim to detect structural changes in the way the node clusters interact with each other. The building block of this thesis is the stochastic block model (SBM), a probabilistic approach initially used in social sciences. The standard SBM assumes that the nodes of a graph belong to hidden (disjoint) clusters and that the probability of observing an edge between two nodes only depends on their clusters. Since no further assumption is made on the connection probabilities, SBM is a very flexible model able to detect different network topologies (hubs, stars, communities, etc.)
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Hamidi, Babak. "Distinguished ground improvement projects by dynamic compaction or dynamic replacement." Thesis, Curtin University, 2014. http://hdl.handle.net/20.500.11937/66.
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Dynamic compaction is a popular ground improvement technique, and has been the subject of various research. However consolidated and comprehensive information on the subject is outdated, and publications remain scattered. In this thesis previously published researches have been collected, reviewed, commented on and compiled into a thorough and comprehensive document. Additionally, previously unpublished state-of-the-art dynamic compaction projects have been described, reviewed, analysed, compared with earlier research, and new formulations and calculation methods have been developed.
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Castro, Arnoldo. "Modeling and dynamic analysis of a two-wheeled inverted-pendulum." Thesis, Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/44897.
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There is a need for smaller and more economic transportation systems. Two-wheeled inverted-pendulum machines, such as the Segway, have been proposed to address this need. However, the Segway places the operator on top of a naturally unstable platform that is stabilized by means of a control system. The control stability of the Segway can be severely affected when minor disturbances or unanticipated conditions arise. In this thesis, a dynamic model of a Segway is developed and used in simulations of various conditions that can arise during normal use. The dynamic model of a general two-wheeled inverted pendulum and human rider is presented. Initial estimates of the parameters were calculated or obtained from other references. The results from numerous experiments are presented and used to develop a better understanding of the dynamics of the vehicle. The experimental data was then used to adjust the model parameters to match the dynamics of a real Segway Human Transporter. Finally, the model was used to simulate various failure conditions. The simulations provide a better understanding of how these conditions arise, and help identify which parameters play an important role in their outcome.
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Fischer, Simon. "Dynamic selfish routing." [S.l.] : [s.n.], 2007. http://deposit.ddb.de/cgi-bin/dokserv?idn=985433612.
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Strauss, Martin. "Dynamic market simulations." Zürich : ETH, Eidgenössische Technische Hochschule Zürich, Dept. für Informatik, 2001. http://e-collection.ethbib.ethz.ch/show?type=dipl&nr=45.
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Almgren, Björn. "Dynamic load modulation." Thesis, University of Gävle, Department of Technology and Built Environment, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:hig:diva-702.
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The purpose of this master thesis was to study if the drain efficiency of power amplifiers can be maintained at power back off using a technique called load modulation.
The amplifier classes studied are E, F and D-1. The target figure was to obtain a 10 to 12 dB dynamic range of amplitude with reasonable efficiency. Studies of power amplifiers have been made to understand how power is generated. Several different load modulation networks have been evaluated. Attempts to derive design equations for the modulation networks have also been done.
The thesis work was carried out with simulations in ADS 2006. As active devices commercially available bare-die transistor models have been used. The power rating of the dies are 15 W.
A dynamic range of amplitude of over 15 dB has been achieved with drain efficiency greater than 60 percent. The peak output power is in the 40 – 45 dBm range.
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Jayaraman, Shankar. "Dynamic cutback optimization." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33812.
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The focus of this thesis is to develop and evaluate a cutback noise minimization process - also known as dynamic cutback optimization - that considers engine spool down during thrust cutback and is consistent with ICAO and FAR Part 36 noise certification procedures.
Simplified methods for flyover EPNL prediction used by propulsion designers assume instantaneous thrust reduction and do not take into account the spooling down of the engine during the cutback procedure. The thesis investigates if there is an additional noise benefit that can be gained by modeling the engine spool down behavior. This in turn would improve the margin between predicted EPNL and Stage 4 noise regulations.
Modeling dynamic cutback also impacts engine design during the preliminary and detailed design stages. Reduced noise levels due to cutback may be traded for lower engine fan diameter, which in turn reduces weight, fuel burn, and cost.
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Horsch, Michael C. "Dynamic Bayesian networks." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/28909.
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Given the complexity of the domains for which we would like to use computers as reasoning
engines, an automated reasoning process will often be required to perform under some state of uncertainty. Probability provides a normative theory with which uncertainty can be modelled. Without assumptions of independence from the domain, naive computations of probability are intractible. If probability theory is to be used effectively in AI applications,
the independence assumptions from the domain should be represented explicitly, and used to greatest possible advantage. One such representation is a class of mathematical structures called Bayesian networks.
This thesis presents a framework for dynamically constructing and evaluating Bayesian networks. In particular, this thesis investigates the issue of representing probabilistic knowledge which has been abstracted from particular individuals to which this knowledge
may apply, resulting in a simple representation language. This language makes the independence assumptions for a domain explicit.
A simple procedure is provided for building networks from knowledge expressed in this language. The mapping between the knowledge base and network created is precisely defined, so that the network always represents a consistent probability distribution.
Finally, this thesis investigates the issue of modifying the network after some evaluation has taken place, and several techniques for correcting the state of the resulting model are derived.Science, Faculty of
Computer Science, Department of
Graduate
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O'Neill, George C. "Dynamic electrophysiological connectomics." Thesis, University of Nottingham, 2016. http://eprints.nottingham.ac.uk/33502/.
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The human brain can be divided into multiple areas, each responsible for different aspects of behaviour. For a century we have been developing techniques to non-invasively map these areas and their associated functions, a discipline now known as neuroimaging. In recent years the field has undergone a paradigm shift to investigate how the brain communicates with itself; it is widely regarded that healthy brain function relies upon efficient connectivity between different functional areas, and the neuroimaging field has been revolutionised by our ability to estimate this connectivity. Studies into communication between spatially separate locations in the brain have revealed a series of robust functional networks which govern mental processes. However these studies have been based on the temporal averaging of minutes or even hours of data to give us a generalised ’snapshot’ of connectivity. Increasing evidence shows us that these connections are dynamic in space, time and frequency and so the next generation of of neuroimaging methods, which capture this 5-dimensional connectivity will prove to be key tools in the investigation of brain networks and ultimately their breakdown in disease. In this thesis we introduce novel methods to capture non-stationarity using magnetoencephalography (MEG), an imaging modality which measures the changes in extracranial magnetic fields associated with neuronal current flow. MEG is a direct measurement of neural activity and has an excellent temporal resolution, which makes it attractive for non-invasively tracking dynamic functional connections. However there are many technical limitations which can confound assessment of functional connectivity which have to be addressed. In Chapters 2 and 3 we introduce the theory behind MEG; specifically how it is possible to measure the femtoTelsa changes in magnetic field generated by the brain and how to project these data to generate a 3-dimensional picture of current in the brain. Chapter 4 reviews some of popular methods of assessing functional connectivity and how to control for the influence of artefactual functional connections erroneously produced during source projection. Chapter 5 introduces a pipeline to assess functional connections across time, space and frequency and in Chapter 6 we apply this pipeline to show that resting state networks, measured using ’static’ metrics are in fact comprised of a series of rapidly forming and dissolving subnetwork connections. Finally, Chapter 7 introduces a pipeline to track dynamic network behaviour simultaneously across the entire brain volume and shows that networks can be characterised by their temporal signatures of connectivity.
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Desruisseaux, Bernard. "Random dynamic fonts." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0007/MQ29682.pdf.
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Birabassov, Rouslan. "Dynamic holographic gratings." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ60763.pdf.
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Heesakkers, Johannes Petrus Franciscus Antonius. "Dynamic urinary graciloplasty." Maastricht : Maastricht : Universiteit Maastricht ; University Library, Maastricht University [Host], 1997. http://arno.unimaas.nl/show.cgi?fid=6278.
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Hemert, Otto Anthonie Christoffel van. "Dynamic investor decisions." [Amsterdam] : Amsterdam : Thela Thesis ; Universiteit van Amsterdam [Host], 2006. http://dare.uva.nl/document/23503.
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Zhang, Yan. "Dynamic programming speedups /." View abstract or full-text, 2007. http://library.ust.hk/cgi/db/thesis.pl?CSED%202007%20ZHANGY.
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Winroth, Harald. "Dynamic projective geometry." Doctoral thesis, Stockholm : Tekniska högsk, 1999. http://www.lib.kth.se/abs99/winr0324.pdf.
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Sanyal, Suman. "Stochastic dynamic equations." Diss., Rolla, Mo. : Missouri University of Science and Technology, 2008. http://scholarsmine.mst.edu/thesis/pdf/Sanyal_09007dcc80519030.pdf.
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Thesis (Ph. D.)--Missouri University of Science and Technology, 2008.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed August 21, 2008) Includes bibliographical references (p. 124-131).
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Hamache, Violette. "Dynamic Ground Clearance." Thesis, Linköpings universitet, Mekanik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-93685.
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The purpose of this work is to develop a test method which will consider the variation of the ground clearance when driving, the so-called dynamic ground clearance. This has been done through the analysis of a specific application: the tractors in grain used in Brazil. Series of real life tests are run in order to obtain data on the tire compressions and the suspension travels. The tractor used is a 6x4 and is loaded with a trailer. When investigating critical cases, the minimum dynamic ground clearance is found to be as small as 123 mm at the axle 1, 78 mm at the exhaust outlet, 137 mm at the fuel tank, 35 mm at the bumper and 213 mm at the axle 2. These data will be transmitted to the engineer responsible for the chassis design in order for him to get a better understanding of the motion of the truck relative to ground.
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Steiner, Lydia. "The Dynamic Epigenome." Doctoral thesis, Universitätsbibliothek Leipzig, 2013. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-119746.
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There is a genome in a cell, as everyone knows, but there is also an epigenome. The epigenome regulates the transcription of the underlying genome. In the last decade, it was discovered that the epigenome state and its regulation are important for differentiation and
development. Correlation studies with aging samples had led to the hypothesis that misregulation of the epigenome causes aging and cancer. Furthermore, diseases were identified which are caused by
errors in the epigenome state and its regulation.
Identification of erroneous epigenome states and misregulation requires the prior knowledge of the common state. Several studies
aim at measuring epigenome states in different organisms and cell
types and thus, provide a huge amount of data.
In this dissertation, a pipeline is developed to analyze and characterize histone modifications with respect to different cell types. Application of this pipeline is shown for a published data set of mouse consisting of data for H3K4me3, H3K27me3, and H3K9me3 measured in embryonic stem cells, embryonic fibroblasts and neuronal progenitors.
Furthermore, methods for the detection of the epigenetic patterns are
presented in this dissertation. Therefore, a segmentation method is developed to segment the genome guided by the data sets. Based on this segmentation, the epigenome states as well as epigenetic variation can be studied. Different visualization methods are developed to highlight the epigenetic patterns in the segmentation data. Application of the segmentation AND visualization methods to the mouse data set had resulted in not only colorful squares but also in biological conclusions! It demonstrate the power of the developed methods.
Although the studied data set in this dissertation contains only ordinary tissue cells, the methods are not restricted to study the reference epigenome state. Comparison of normal and disease cells as well as comparison with aged cells are possible with all of the methods.
Finally, the methods are compared based on the obtained results. It shows that all methods highlight different aspects of the data. Thus, applying all methods to the same data sets, deep insights into the epigenome in murine embryonic stem cells, embryonic fibroblasts and
neuronal progenitor cells are gained. For example, it had been found
that several mechanisms exist setting H3K4me3 marks. Furthermore, not all mechanisms are found in all cell types. Strong evidence had been
found that catalysis of H3K4me3 and H3K27me3 is coupled.
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Desruisseaux, Bernard. "Random dynamic fonts." Thesis, McGill University, 1996. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=27307.
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This thesis presents a general method and structure for storing, representing and reproducing random dynamic fonts, i.e., fonts whose each rendition of each letterform differs. Such fonts allow, e.g., to come closer to simulating true handwriting, by rendering its freedom, spontaneity, and unpredictability.This method allows the generation of random letterforms with different overall shapes, derived from single letterform descriptions, according to specified parameters and constraints. Letterforms generated in this manner remain closely related--to a certain extent--to the original letterforms, and preserve the continuity and thickness of the strokes.
Several examples of a typeface family designed with this method, implemented as PostScript Type 3 font programs, are presented. A survey of the literature on random dynamic fonts is also proposed.
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Paterson, Maura Beth. "Dynamic frameproof codes." Thesis, Royal Holloway, University of London, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424457.
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