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Možnosti využití nových medií v oblasti formálního vzdělávaní: Případová studie návrhu historické simulace / The use of new media in formal education: A case study of design of the historical simulationLekovski, Michael January 2012 (has links)
Thesis was developed as a model specification for a design of historical simulation applied in formal education. The text is divided into two main parts: The theoretical part summarizes findings about the role of new media in e-learning and its potential enrichment for gamification elements. Also mentions computer game as a research subject and points to the game mechanics that can be used in formal education to a successful application DGBL - Digital Game-Based Learning in this process. Practical part presents case study of a model specification that is based on the real project: 'Stories from the History of Czechoslovakia: Research and experimental development of software simulations to teach the history of the Czech lands in the 20th Century", solved by Faculty of Arts and Facility of Mathematics and Physics of Charles University and Institute of Contemporary History of Academy of Sciences of Czech Republic in Prague in 2011- 2014. In this section are addressed by specific examples of model applications of gamification elements with a view to achieving the educational goals of teaching simulation.
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Regulation of Permeation in AquaporinsKaptan, Shreyas Sanjay 23 March 2015 (has links)
No description available.
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A Grid-Adaptive Algebraic Hybrid RANS/LES MethodReuß, Silvia 16 December 2015 (has links)
No description available.
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COMPARISON OF FILE TRANSFER USING SCPS FP AND TCP/IP FTP OVER A SIMULATED SATELLITE CHANNELHoran, Stephen, Wang, Ru-hai 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The CCSDS SCPS FP file transfer performance is compared with that of TCP/IP FTP in
a simulated satellite channel environment. The comparison is made as a function of
channel bit error rate and forward/return data rates. From these simulations, we see that
both protocols work well when the channel error rate is low (below 10^-6) and the SCPS
FP generally performs better when the error rate is higher. We also noticed a strong effect
on the SCPS FP throughput as a function of forward transmission rate when running
unbalanced channel tests.
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Distributed Interactive Simulation (DIS): An Overview Of The System And Its Potential UsesBoyd, Edward L., Novits, Charles S., Boisvert, Robert A. 10 1900 (has links)
International Telemetering Conference Proceedings / October 17-20, 1994 / Town & Country Hotel and Conference Center, San Diego, California / The Distributed Interactive Simulation (DIS) concept, since its inception, has been
defined into three separate but distinct areas of service.
• Viewing of data in the real-time environment.
• Multiple range viewing and usage of"real-time data."
• Problems with the sharing of information through DIS.
This paper will discuss the DIS concept and some of the various methods available to
display this data to users of the system.
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Micromagnetic simulations for the investigation of magnetic vortex array dynamicsCiuciulkaite, Agne January 2016 (has links)
In this work the dynamics of permalloy circular magnetic islands of 225 nm radius and 10 nm thickness arranged into square lattices was investigated employing micromagnetic simulations.The simulations of the vortex magnetization loops and the ferromagnetic resonance (FMR) spectra were carried out using a free micromagnetics simulation software Mumax3. The obtained data was analyzed using Matlab. The simulations were carried out on a single vortex island as well as on two different lattices. The first lattice is comprised of interacting islands, while the second lattice - of non-interacting islands, separated by 25 nm and by 450 nm edge-to-edge distance, respectively. The magnetization loops were simulated by applying the static magnetic field in-plane of the single island or the lattice. The FMR simulations were carried out by applying the static magnetic field in-plane of the lattice and after the system reached the ground state in that field, the excitation as a sinc pulse was sent out along the out-of-plane direction of the lattice. The analysis of the obtained FMR spectra revealed that the several resonant modes are present for the single vortex island and the lattice, comprised of such islands. However, the physical explanation of the origin of those modes is a subject for further investigations.
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Computer simulations of polymers and gelsWood, Dean January 2013 (has links)
Computer simulations have become a vital tool in modern science. The ability to reliably move beyond the capabilities of experiment has allowed great insights into the nature of matter. To enable the study of a wide range of systems and properties a plethora of simulation techniques have been developed and refined, allowing many aspects of complex systems to be demystified. I have used a range of these to study a variety of systems, utilising the latest technology in high performance computing (HPC) and novel, nanoscale models. Monte Carlo (MC) simulation is a commonly used method to study the properties of system using statistical mechanics and I have made use of it in published work [1] to study the properties of ferrogels in homogeneous magnetic fields using a simple microscopic model. The main phenomena of interest concern the anisotropy and enhancement of the elastic moduli that result from applying uniform magnetic fields before and after the magnetic grains are locked in to the polymer-gel matrix by cross-linking reactions. The positional organization of the magnetic grains is influenced by the application of a magnetic field during gel formation, leading to a pronounced anisotropy in the mechanical response of the ferrogel to an applied magnetic field. In particular, the elastic moduli can be enhanced to different degrees depending on the mutual orientation of the fields during and after ferrogel formation. Previously, no microscopic models have been produced to shed light on this effect and the main purpose of the work presented here is to illuminate the microscopic behaviour. The model represents ferrogels by ensembles of dipolar spheres dispersed in elastic matrices. Experimental trends are shown to be reflected accurately in the simulations of the microscopic model while shedding light on the microscopic mechanism causing these effects. These mechanisms are shown to be related to the behaviour of the dipoles during the production of the gels and caused by the chaining of dipoles in magnetic fields. Finally, simple relationships between the elastic moduli and the magnetization are proposed. If supplemented by the magnetization curve, these relationships yield the dependencies of the elastic moduli on the applied magnetic field, which are often measured directly in experiments. While MC simulations are useful for statistical studies, it can be difficult to use them to gather information about the dynamics of a system. In this case, Molecular Dynamics (MD) is more widely used. MD generally utilises the classical equations of motion to simulate the evolution of a system. For large systems, which are often of interest, and multi-species polymers, the required computer power still poses a challenge and requires the use of HPC techniques. The most recent development in HPC is the use of Graphical Processing Units (GPU) for the fast solution of data parallel problems. In further published work [2], I have used a bespoke MD code utilising GPU acceleration in order to simulate large systems of block copolymers(BC) in solvent over long timescales. I have studied thin films of BC solutions drying on a flat, smooth surface which requires long timescales due to the ’slow’ nature of the process. BC’s display interesting self-organisation behaviour in bulk solution and near surfaces and have a wide range of potential applications from semi-conductors to self-constructing fabrics. Previous studies have shown some unusual behaviour of PI-PEO diblock co-polymers adsorbing to a freshly cleaved mica surface. These AFM studies showed polymers increasing in height over time and proposed the change of affinity of mica to water and the loss of water layers on the surface as a driver for this change. The MD simulation aimed to illuminate the process involved in this phenomena. The process of evaporation of water layers from a surface was successfully simulated and gave a good indication that the process of solvent evaporation from the surface and the ingress of solvent beneath the adsorbed polymer caused the increase in height seen in experiment.
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Simulation and Measurement of Wheel on Rail Fatigue and WearDirks, Babette January 2015 (has links)
The life of railway wheels and rails has been decreasing in recent years. This is mainly caused by more traffic and running at higher vehicle speed. A higher speed usually generates higher forces, unless compensated by improved track and vehicle designs, in the wheel-rail contact, resulting in more wear and rolling contact fatigue (RCF) damage to the wheels and rails. As recently as 15 years ago, RCF was not recognised as a serious problem. Nowadays it is a serious problem in many countries and ''artificial wear'' is being used to control the growth of cracks by preventive re-profiling and grinding of, respectively, the wheels and rails. This can be used because a competition exists between wear and surface initiated RCF: At a high wear rate, RCF does not have the opportunity to develop further. Initiated cracks are in this case worn off and will not be able to propagate deep beneath the surface of the rail or wheel. When wheel-rail damage in terms of wear and RCF can be predicted, measures can be taken to decrease it. For example, the combination of wheel and rail profiles, or the combination of vehicle and track, can be optimised to control the damage. Not only can this lead to lower maintenance costs, but also to a safer system since high potential risks can be detected in advance. This thesis describes the development of a wheel-rail life prediction tool with regard to both wear and surface-initiated RCF. The main goal of this PhD work was to develop such a tool where vehicle-track dynamics simulations are implemented. This way, many different wheel-rail contact conditions which a wheel or a rail will encounter in reality can be taken into account. The wear prediction part of the tool had already been successfully developed by others to be used in combination with multibody simulations. The crack prediction part, however, was more difficult to be used in combination with multibody simulations since crack propagation models are time-consuming. Therefore, more concessions had to be made in the crack propagation part of the tool, since time-consuming detailed modelling of the crack, for example in Finite Elements models, was not an option. The use of simple and fast, but less accurate, crack propagation models is the first step in the development of a wheel-rail life prediction model. Another goal of this work was to verify the wheel-rail prediction tool against measurements of profile and crack development. For this purpose, the wheel profiles of trains running on the Stockholm commuter network have been measured together with the crack development on these wheels. Three train units were selected and their wheels have been measured over a period of more than a year. The maximum running distance for these wheels was 230,000 km. A chosen fatigue model was calibrated against crack and wear measurements of rails to determine two unknown parameters. The verification of the prediction tool against the wheel measurements, however, showed that one of the calibrated parameters was not valid to predict RCF on wheels. It could be concluded that wheels experience relatively less RCF damage than rails. Once the two parameters were calibrated against the wheel measurements, the prediction tool showed promising results for predicting both wear and RCF and their trade-off. The predicted position of the damage on the tread of the wheel also agreed well with the position found in the measurements. / <p>QC 20150526</p>
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Quantification of the confidence that can be placed in land-surface model predictions : applications to vegetation and hydrologic processesGulden, Lindsey Elizabeth 04 February 2010 (has links)
The research presented here informs the confidence that can be placed in the
simulations of land-surface models (LSMs).
After introducing a method for simplifying a complex, heterogeneous land-cover
dataset for use in LSMs, I show that LSMs can realistically represent the spatial
distribution of heterogeneous land-cover processes (e.g., biogenic emission of volatile
organic compounds) in Texas. LSM-derived estimates of biogenic emissions are sensitive
(varying up to a factor of 3) to land-cover data, which is not well constrained by
observations. Simulated emissions are most sensitive to land-cover data in eastern and
central Texas, where tropospheric ozone pollution is a concern. I further demonstrate that
interannual variation in leaf mass is at least as important to variation in biogenic
emissions as is interannual variation in shortwave radiation and temperature. Model estimates show that more-humid regions with less year-to-year variation in precipitation
have lower year-to-year variation in biogenic emissions: as modeled mean emissions
increase, their mean-normalized standard deviation decreases.
I evaluate three parameterizations of subsurface hydrology in LSMs (with (1) a
shallow, 10-layer soil; (2) a deeper, many-layered soil; and (3) a lumped aquifer model)
under increasing parameter uncertainty. When given their optimal parameter sets, all
three versions perform equivalently well when simulating monthly change in terrestrial
water storage. The most conceptually realistic model is least sensitive to errant parameter
values. However, even when using the most conceptually realistic model, parameter
interaction ensures that knowing ranges for individual parameters is insufficient to
guarantee realistic simulation.
LSMs are often developed and evaluated at data-rich sites but are then applied in
regions where data are sparse or unavailable. I present a framework for model evaluation
that explicitly acknowledges perennial sources of uncertainty in LSM simulations (e.g.,
parameter uncertainty, meteorological forcing-data uncertainty, evaluation-data
uncertainty) and that evaluates LSMs in a way that is consistent with models’ typical
application. The model performance score quantifies the likelihood that a representative
ensemble of model performance will bracket observations with high skill and low spread.
The robustness score quantifies the sensitivity of model performance to parameter error
or data error. The fitness score ranks models’ suitability for broad application. / text
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A simulation approach to studying the relationship between landscape features and social system on the genetic structure of a tamarin primate populationValencia Rodriguez, Lina Maria 01 October 2014 (has links)
Landscape genetics is an emerging field that seeks to understand how specific landscape features and microevolutionary processes such as gene flow, genetic drift, and selection interact to shape the amount and spatial distribution of genetic variation. This study explores, through agent based simulations, how the specific mating and social system of tamarin primates (genus Saguinus) influences population genetic structure and patterns of relatedness within and among groups of this primate species, which might affect the ability of landscape genetic studies to detect the effects of fragmentation on gene flow. I use a spatially-explicit agent-based population genetics simulation model (GENESYS) configured to reflect the particular social system of tamarin monkeys (i.e. small group size, limited numbers of breeders per group, frequent twin births, and short dispersal distances) to assess whether the isolation by distance model of genetic differentiation expected in an unfragmented landscape can be distinguished from the isolation by barrier model expected in a fragmented landscape. GENESYS allows a user to explore the effects of social structure and landscape features on the population genetic structure of social animals, such as primates. I simulated two different landscapes containing an otherwise equivalent population of tamarins. In the first setup I simulated a homogeneous landscape unconstrained by any barriers to gene flow, while for the second setup, a barrier to gene flow restricted dispersal from one half of the landscape to the other. I found that the particular mating system of tamarin results in the rapid genetic differentiation of its social groups and consequently its populations. Social groups in the continuous landscape indeed revealed an isolation by distance pattern, while social groups on the fragmented landscape yielded instead an isolation by barrier model, where the barrier rather than geographic distance per se influenced the spatial genetic structure of the population. The results from this study suggest that features of the tamarin social system influence population genetic structure, which could affect the ability of landscape genetic studies to detect the effects of fragmentation on gene flow. To more fully address that issue, future studies should focus on a range of different primate social systems. / text
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