High-quality power generation through distributed control of a power park microgrid

Published versio

Control and filter design of three-phase inverters for high power quality grid connection

Published versio

Demand management for home energy networks using cost-optimal appliance scheduling

This paper uses problem decomposition to show that optimal dynamic home energy prices can be used to reduce the cost of supplying energy, while at the same time reducing the cost of energy for the home users. The paper makes no specific recommendations on the nature of energy pricing, but shows that energy prices can normally be found that not only result in optimal energy consumption schedules for the energy provider's problem and are economically viable for the energy provider, but also reduce total users energy costs. Following this, the paper presents a heuristic real-time algorithm for demand management using home appliance scheduling. The presented algorithm ensures users' privacy by requiring users to only communicate their aggregate energy consumption schedules to the energy provider at each iteration of the algorithm. The performance of the algorithm is evaluated using a comprehensive probabilistic user demand model which is based on real user data from energy provider E.ON. The simulation results show potential reduction of up to 17% of the mean peak-to-average power estimate, reducing the user daily energy cost for up to 14%

Understanding the diffuse gamma ray emission of the milky way - from supernova remnants to dark matter

Diffuse gamma ray emission from the Galactic center at 2-3 GeV, as well as the 12 TeV gamma ray excess in the Galactic disk, remain open for debate and represent the missing puzzles in the complete picture of the high-energy Milky Way sky. Our papers emphasize the importance of understanding all of the populations that contribute to the diffuse gamma background in order to discriminate between the astrophysical sources such as supernova remnants and pulsars, and something that is expected to be seen in gamma rays and is much more exotic - dark matter. We analyze two separate data sets that have been measured in different energy ranges from the ?Fermi-LAT? and ?Milagro? telescopes, using these as a powerful tool to limit and test our analytical source population models. We model supernova remnants and pulsars, estimating the number of still undetected ones that contribute to the diffuse background, trying to explain both the Galactic center and the 12 TeV excess. Furthermore, we aim to predict the number of soon to be detected sources with new telescopes, such as the ?HAWC?

Multiscale modeling of twitch contractions in cardiac trabeculae

© 2021 Mijailovich et al. Understanding the dynamics of a cardiac muscle twitch contraction is complex because it requires a detailed understanding of the kinetic processes of the Ca2+ transient, thin-filament activation, and the myosin-actin cross-bridge chemomechanical cycle. Each of these steps has been well defined individually, but understanding how all three of the processes operate in combination is a far more complex problem. Computational modeling has the potential to provide detailed insight into each of these processes, how the dynamics of each process affect the complexity of contractile behavior, and how perturbations such as mutations in sarcomere proteins affect the complex interactions of all of these processes. The mechanisms involved in relaxation of tension during a cardiac twitch have been particularly difficult to discern due to nonhomogeneous sarcomere lengthening during relaxation. Here we use the multiscale MUSICO platform to model rat trabecular twitches. Validation of computational models is dependent on being able to simulate different experimental datasets, but there has been a paucity of data that can provide all of the required parameters in a single experiment, such as simultaneous measurements of force, intracellular Ca2+ transients, and sarcomere length dynamics. In this study, we used data from different studies collected under similar experimental conditions to provide information for all the required parameters. Our simulations established that twitches either in an isometric sarcomere or in fixed-length, multiple-sarcomere trabeculae replicate the experimental observations if models incorporate a length-tension relationship for the nonlinear series elasticity of muscle preparations and a scheme for thick-filament regulation. The thick-filament regulation assumes an off state in which myosin heads are parked onto the thick-filament backbone and are unable to interact with actin, a state analogous to the super-relaxed state. Including these two mechanisms provided simulations that accurately predict twitch contractions over a range of different conditions

Organic Lamb Meat Production in Serbia Based on Autochthonous Zackel Breed: Opportunities and Challenges

The global growing tendency of lamb and mutton meat production has been emphasized. The fastest growing meat production industry on a global level is lamb and mutton meat production. Lamb meat production increase is primarily based on genetic improvement of sheep breeds, reproduction management and disease reduction. The new Strategy for Agriculture and Rural Development in Serbia from 2014 to 2024 defines goals and priorities for further development of agriculture. One of priority topics is the promotion of organic production. Organic lamb production is a great opportunity for rural regions development. Botanical composition analyses, as well as plants nutrition value, have shown that natural resources of regions in Serbia have great potentials for organic lamb production. Basic principles of organic production promote well adapted, autochthonous breeds. Various types of Zackel sheep are important genetic resources, evolutionary adapted on specific conditions and extreme climate. The study evaluated the value of various types of Zackel sheep populations in the regions where they are traditionally reared with special emphasis on some traits such as health status and robustness, important for organic production. Disease frequency analysis in different Zackel type populations has shown that gastrointestinal parasitic infections represent the main health problem in sheep farming. The introduction of veterinary medicine standards in organic sheep production is a great challenge. Considering that conventional prevention and medication are forbidden in organic production, veterinary control of parasitic infections is not satisfying. Our investigations are focused on preventive measure and genetic resistance/tolerance to parasitic infections of various types of Zackel sheep as very important for organic lamb production