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To study the interaction of wind farms with mesoscale effects and with neighboring wind farms we develop and employ high-fidelity large-eddy simulations (LES). These simulations resolve the equations of motion for scales larger than the grid size, while smaller scale motions are modelled with sub-grid scale (SGS) models. Consequently, the accuracy of LES is highly dependent on the SGS model used to parameterize these processes. In Part I we determine the most suitable SGS for large scale simulations. We show that LES using either the anisotropic minimum dissipation (AMD) or the computational more expensive Lagrangian-averaged scale-dependent (LASD) SGS model agrees better with measurements and theoretical predictions than LES using the Smagorinsky model. Furthermore, the effect of selected mesoscale processes is modeled and investigated in microscale LES of wind farms. Here, microscale refers to domain sizes smaller than a few hundred square kilometers. In contrast, mesoscale processes, such as different weather phenomena, cannot be explicitly simulated in microscale domains and must be modeled. Here, we introduce a method to include dynamic wind direction changes, originating from mesoscale atmospheric flow phenomena, in microscale LES. We show that these dynamic wind direction changes can positively and negatively affect the power production of wind farms. Additionally, we include negative geostrophic shear in the LES and show that this phenomenon creates an upward flux above the low-level jet which limits the energy entrainment into the wind farm. In Part II, wind farm wakes and their impact on downstream positioned wind farms are analyzed using LES. We show that the performance of the leading row and the wake recovery of the downstream farm are highly impacted by the wake of the upstream farm. The results are used for an evaluation of the wind farm wake recovery predicted by engineering models. We find that all engineering models under consideration overestimate the wind farm wake recovery compared to LES observations. Therefore, we conclude that these engineering models must be updated to include the interaction between wind farms.

An important blast injury mechanism is the rupture of the lungs and the gastrointestinal tract. In explosives safety studies and threat analysis the empirical model of Bowen is often used to quantify this mechanism. The original model predicts the lethality for a person in front of a reflecting surface caused by simple Friedlander blast waves. Bowen extended the applicability to persons in prone position and standing in the free field by making assumptions about the pressure dose at these positions. Based on new experimental data, some authors recently concluded that the lethality for a person standing in the free field is the same as for a person in front of a reflecting surface, contrary to Bowen's assumptions.In this article, we show that only for a short duration blast wave, the load on a person standing in the free field is comparable to that on a person in front of a reflecting surface. For long positive phase durations, a safe and conservative assumption is that the load on a person standing in the free field is the sum of the side-on overpressure and the dynamic pressure. This hypothesis is supported by common knowledge about blast waves and is illustrated with numerical blast simulations.In a step by step derivation we present a new standard for the prediction of lethality caused by Friedlander blast waves, which will be included in the NATO Explosives Safety Manual AASTP-4. The result is a comprehensive engineering model that can be easily applied in calculations. © 2016 Elsevier Ltd.

PICASSO - A PICo-satellite for Atmospheric and Space Science Observations is an ESA project led by the Belgian Institute for Space Aeronomy, in collaboration with VTT Technical Research Centre of Finland Ltd, Clyde Space Ltd. (UK) and Centre Spatial de Liège (BE). The test campaign for the engineering model of the PICASSO VISION instrument, a miniaturized nanosatellite spectral imager, has been successfully completed. The test results look very promising. The proto-flight model of VISION has also been successfully integrated and it is waiting for the final integration to the satellite platform. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

Noise control for an urban district starts by understanding the actual noise situation. A correct understanding is needed to take appropriate and cost efficient measures. For a noise burdened urban district, surrounded by road and rail traffic, the traffic noise as well as the annoyance has been measured. The size of the district is approximately one square km. With the help of 35 microphones, applied in a scalable sensor network, the time-varying sound levels were recorded. These results were coupled to an engineering model to obtain the sound levels for the complete district as well as to discriminate between road and rail traffic noise. Also, a data assimilation technique has been applied to increase the agreement between the measurement and model results. For example, for Lden sound levels the standard used source strengths for road and rail needed to be adapted to better match the sound level measurement results. In a separate paper these corrected sound levels at the façades are coupled to annoyance survey results to derive a local exposure-response relation. The annoyance survey also indicated the importance of peak levels and vibrations. This is further investigated by considering the measured noise dynamics.

Noise control for an urban district starts by understanding the actual noise situation. A correct understanding is needed to take appropriate and cost efficient measures. For a noise burdened urban district, surrounded by road and rail traffic, the traffic noise as well as the annoyance has been measured. The size of the district is approximately one square km. With the help of 35 microphones, applied in a scalable sensor network, the time-varying sound levels were recorded. These results were coupled to an engineering model to obtain the sound levels for the complete district as well as to discriminate between road and rail traffic noise. Also, a data assimilation technique has been applied to increase the agreement between the measurement and model results. For example, for Lden sound levels the standard used source strengths for road and rail needed to be adapted to better match the sound level measurement results. In a separate paper these corrected sound levels at the façades are coupled to annoyance survey results to derive a local exposure-response relation. The annoyance survey also indicated the importance of peak levels and vibrations. This is further investigated by considering the measured noise dynamics.

At TNO several energy-based engineering models have been created for various failure mechanism occurring in ballistic testing of materials, like ductile hole growth, denting, plugging, etc. Such models are also under development for ceramic and fiberbased materials (fabrics). As the models are energy-based they can be directly compared to experimental results of ballistic tests as the mass and velocities of projectiles are regularly measured. This allows the models to be validated, as has been done for the ductile hole growth model. Using AP-rounds on ductile target materials like many metals, clay and polymers, ductile hole growth (DHG) normally is the major failure mechanism during projectile penetration. When the core of the projectile remains rigid (which is often the case in ductile materials) the loss in kinetic energy of the core is easily measured from its initial and residual velocity. In the DHG-engineering model this energy loss is also calculated but requires that the flow stress at high strain rates is known. Using the experimental results in combination with this engineering model the dynamic flow stress of the target has been quantified. This procedure has been done for several material (metals, clay types and polymers) and allows the determination of dynamic material properties that are otherwise not easily measured. This method requires a rigid penetration of a projectile through a (thick) plate of the material to be characterized. Hence, no special sample shape or dimension is required. The dynamic flow stresses that are obtained have been compared to high strain rate (order 1000/s) strength values of the same materials determined by other techniques. As the values are very close to each other, this provides confidence in the approach to use ballistic test results of targets failed by DHG in combination with the engineering model for the characterization of materials at high strain rates.

At TNO several energy-based engineering models have been created for various failure mechanism occurring in ballistic testing of materials, like ductile hole growth, denting, plugging, etc. Such models are also under development for ceramic and fiberbased materials (fabrics). As the models are energy-based they can be directly compared to experimental results of ballistic tests as the mass and velocities of projectiles are regularly measured. This allows the models to be validated, as has been done for the ductile hole growth model. Using AP-rounds on ductile target materials like many metals, clay and polymers, ductile hole growth (DHG) normally is the major failure mechanism during projectile penetration. When the core of the projectile remains rigid (which is often the case in ductile materials) the loss in kinetic energy of the core is easily measured from its initial and residual velocity. In the DHG-engineering model this energy loss is also calculated but requires that the flow stress at high strain rates is known. Using the experimental results in combination with this engineering model the dynamic flow stress of the target has been quantified. This procedure has been done for several material (metals, clay types and polymers) and allows the determination of dynamic material properties that are otherwise not easily measured. This method requires a rigid penetration of a projectile through a (thick) plate of the material to be characterized. Hence, no special sample shape or dimension is required. The dynamic flow stresses that are obtained have been compared to high strain rate (order 1000/s) strength values of the same materials determined by other techniques. As the values are very close to each other, this provides confidence in the approach to use ballistic test results of targets failed by DHG in combination with the engineering model for the characterization of materials at high strain rates.

Lots of engineering modeling methods have been designed to investigate and analyze complex systems, such as artificial life, cellular automata and artificial society. Artificial society is a bottom-up modeling method which is a new paradigm of simulating human society from bottom up. A great amount of work has used the artificial society method. However, how to engineering modeling artificial society with unconventional emergency is still worth to research. In this paper, we take into account the particularity of unconventional emergency management to research artificial society modeling with the viewpoint of software engineering. Then, we propose an unconventional emergency management-oriented artificial society model, including agent model, environment agent model and emergency model. Furthermore, agents in the artificial society adopt the self-adaptive approach -binding mechanism, including role binding and emergency model binding. Then, the proposed model is illustrated by an example of H1N1.