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The development of machine learning research has provided statistical innovations and further developments within the field of time series analysis. This study seeks to investigate two different approaches on artificial neural network models based on different learning techniques, and answering how well the neural network approach compares with a basic autoregressive approach, as well as how the artificial neural network models compare to each other. The models were compared and analyzed in regards to the univariate forecast accuracy on 20 randomly drawn time series from two different time frequencies from the M4 competition dataset. Forecasting was made dependent on one time lag (t-1) and forecasted three and six steps ahead respectively. The artificial neural network models outperformed the baseline Autoregressive model, showing notably lower mean average percentage error overall. The Multilayered perceptron models performed better than the Long short-term memory model overall, whereas the Long short-term memory model showed improvement on longer prediction time dimensions. As the training were done univariately on a limited set of time steps, it is believed that the one layered-approach gave a good enough approximation on the data, whereas the added layer couldn’t fully utilize its strengths of processing power. Likewise, the Long short-term memory model couldn’t fully demonstrate the advantagements of recurrent learning. Using the same dataset, further studies could be made with another approach to data processing. Implementing an unsupervised approach of clustering the data before analysis, the same models could be tested with multivariate analysis on models trained on multiple time series simultaneously.

El concepto de servicio hidrometeorológico, climático y medioambiental urbano integrado ha sido propuesto por la OMM para satisfacer las necesidades futuras de sus Miembros, especialmente para lograr los Objetivos de Desarrollo Sostenible de las Naciones Unidas. UrbanSIS en Estocolmo es una excelente demostración de una iniciativa de integración de diversas disciplinas científicas de una forma holística e innovadora. Los modelos meteorológicos, de calidad del aire e hidrológicos se usan para proporcionar datos de alta resolución espacial (1 km) y temporal (15 minutos a 1 hora) para el diseño y la planificación urbanas de manera vanguardista y ecocéntrica. La iniciativa de la OMM se emprendió cooperativamente y en colaboración con otras ciudades –Bolonia y Rotterdam– para desarrollar y generalizar eficientemente su capacidad. La OMM está siguiendo la Guía para los servicios hidrometeorológicos, climáticos y medioambientales urbanos integrados, Parte 1: Concepto y Metodología con ejemplos adicionales de ciudades de muestra con la mayor diversidad económica, geográfica y de riesgos.

Reinforced rubber is thanks to its elastic and dissipative properties found in industrialapplications such as isolators, flexible joints and tires. Its dissipative propertied comes from material related losses which have the effect that energy invested when deforming the material is not retained when returning it back to its initial state. The materiallosses are in turn caused by interactions in the material on a level below the micro scale.These interaction forms a macro stress strain response that is dependent on both strainamplitude, strain rate and temperature.It is thus a challenge to accurately model components made of reinforced rubber andand features of interest related to them, such as the rolling resistance for a tire. It is also difficult to device general design guide lines for such components due to rubbers many and complex dependencies and a simple accurate phenomenological model for modeling these properties are highly sought for in industry today.This thesis presents a method for modeling the strain amplitude and strain rate behavior for cyclically loaded rubber along with a method of choosing its material parameters.The proposed modeling technique results in a model with the same frequencydependency over all strain rates. An approximation which is shown to be valid over a few decades of strain amplitudes and rates and is believed useful for many industrialapplications. The material model presented can in addition be implemented in commercial FEsoftwares by using only pre-defined material models. This was achieved by implementationof the overlay method. The thesis also presents a method for how to implement the modeling technique in simulations with purpose to determine the rolling resistance of a truck tyre. Förstärkt gummi används, tack vare sina elastiska och dissipativa egenskaper, i industriella komponenter som exempelvis bussningar i drivlinan, däck och flexibla gummikopplingar. Dissipationen orsakas av materialförluster som i sin tur orsakas av interaktioner på längdskalor kortare än micro-nivå i materialet. Dessa Interaktioner resulterar i ett material som mekaniskt kan klassificeras som ett ickelinjärt material beroende av töjningsamplitud, töjningshastighet och temperatur. Det är därför en utmaning att göra modeller som på ett korrekt sätt förutsäger beteendet för gummikomponenter och egenskaper relaterade till dessa, som exempelvis rullmotståndet i ett däck. Det är även svårt att ge generella design riktlinjer för dessa komponenter på grund gummits många materialberoenden och enkla användvändbara fenomenologiska modeller som kan underlätta vid sådana processer är därför högt efterfrågade av industrin idag. I denna rapport presenteras en materialmodell för att modellera töjningsamplitud och töjningshastighetsberoendet för gummi under cyklisk last samt en metod för att välja dess materialparametrar. Den föreslagna materialmoddeleringstekniken resulterar i en modell med samma töjningshastighetsberoende för alla töjningsamplituder. En approximation som är användbar inom ett antal decader av töjningsamplituder och töjningshastigheter vilket borde vara tillräckligt för de flesta industriella tillämpningar idag. Den föreslagna materialmodellen kan dessutom implementeras i kommersiella FEprogramvaror genom att endast använda i programmet inbyggda materialmodeller. Detta sker genom tillämpning av overlay-metoden. I rapporten presenteras även en metod förhur modelleringstekniken kan implementeras genom en tillämpning i simuleringar med syfte att bestämma rullmotståndet för ett lastbilsdäck.

Reinforced rubber is thanks to its elastic and dissipative properties found in industrialapplications such as isolators, flexible joints and tires. Its dissipative propertied comes from material related losses which have the effect that energy invested when deforming the material is not retained when returning it back to its initial state. The materiallosses are in turn caused by interactions in the material on a level below the micro scale.These interaction forms a macro stress strain response that is dependent on both strainamplitude, strain rate and temperature.It is thus a challenge to accurately model components made of reinforced rubber andand features of interest related to them, such as the rolling resistance for a tire. It is also difficult to device general design guide lines for such components due to rubbers many and complex dependencies and a simple accurate phenomenological model for modeling these properties are highly sought for in industry today.This thesis presents a method for modeling the strain amplitude and strain rate behavior for cyclically loaded rubber along with a method of choosing its material parameters.The proposed modeling technique results in a model with the same frequencydependency over all strain rates. An approximation which is shown to be valid over a few decades of strain amplitudes and rates and is believed useful for many industrialapplications. The material model presented can in addition be implemented in commercial FEsoftwares by using only pre-defined material models. This was achieved by implementationof the overlay method. The thesis also presents a method for how to implement the modeling technique in simulations with purpose to determine the rolling resistance of a truck tyre. Förstärkt gummi används, tack vare sina elastiska och dissipativa egenskaper, i industriella komponenter som exempelvis bussningar i drivlinan, däck och flexibla gummikopplingar. Dissipationen orsakas av materialförluster som i sin tur orsakas av interaktioner på längdskalor kortare än micro-nivå i materialet. Dessa Interaktioner resulterar i ett material som mekaniskt kan klassificeras som ett ickelinjärt material beroende av töjningsamplitud, töjningshastighet och temperatur. Det är därför en utmaning att göra modeller som på ett korrekt sätt förutsäger beteendet för gummikomponenter och egenskaper relaterade till dessa, som exempelvis rullmotståndet i ett däck. Det är även svårt att ge generella design riktlinjer för dessa komponenter på grund gummits många materialberoenden och enkla användvändbara fenomenologiska modeller som kan underlätta vid sådana processer är därför högt efterfrågade av industrin idag. I denna rapport presenteras en materialmodell för att modellera töjningsamplitud och töjningshastighetsberoendet för gummi under cyklisk last samt en metod för att välja dess materialparametrar. Den föreslagna materialmoddeleringstekniken resulterar i en modell med samma töjningshastighetsberoende för alla töjningsamplituder. En approximation som är användbar inom ett antal decader av töjningsamplituder och töjningshastigheter vilket borde vara tillräckligt för de flesta industriella tillämpningar idag. Den föreslagna materialmodellen kan dessutom implementeras i kommersiella FEprogramvaror genom att endast använda i programmet inbyggda materialmodeller. Detta sker genom tillämpning av overlay-metoden. I rapporten presenteras även en metod förhur modelleringstekniken kan implementeras genom en tillämpning i simuleringar med syfte att bestämma rullmotståndet för ett lastbilsdäck.

Weather and climate models applied with sufficiently fine mesh grids to enable a large part of atmospheric deep convection to be explicitly resolved have shown a significantly improved representation of local, short-duration and intense precipitation events compared to coarser scale models. In this thesis, two studies are presented aimed at exploring the dependence of horizontal resolution and of parameterization of convection on the simulation of precipitation. The first examined the ability of HARMONIE Climate (HCLIM) regional climate model to reproduce the recent climate in Europe with two different horizontal resolutions, 15 and 6.25 km. The latter is part of the ”grey-zone” resolution interval corresponding to approximately 3-10 km. Particular focus has been given to rainfall and its spatial and temporal variability and other characteristics, for example intensity distributions. The model configuration with the higher resolution is much better at simulating days of large accumulated precipitation amounts, most evident when the comparison is made against high-resolution observations. Otherwise, the two simulations show similar skill, including the representation of the spatial structure of individual rainfall areas of primarily convective origin. The results suggest a ”scale-awareness” in HCLIM, which supports a central feature of the model’s description of deep convection as it is designed to operate independently of the horizontal resolution. In the second study, summer season precipitation over the Alps region, as simulated by HCLIM at different resolutions, is investigated. Similar model configurations as in the previous study were used, but in addition a simulation at the ”convection-permitting” 2 km resolution has been made over Central Europe. The latter considerably increases the realism compared to the former regarding the distribution and intensities of precipitation, as well as other important characteristics including the duration of rain spells, particularly on sub-daily time scales and for extreme events. The simulations with cumulus parameterization active underestimate short-duration heavy rainfall, and rainspells with low peak intensities are too persistent. Furthermore, even though the 6.25 km simulation generally reduces the biases seen in the 15 km run, definitive conclusions of the benefit of ”grey-zone” resolution is difficult to establish in context of the increased requirement of computer resources for the higher-resolution simulation.