A5091466494- Arctic and Antarctic ice dynamics
- Methane Hydrates and Related Phenomena
- Advanced Power Amplifier Design
- Radio Frequency Integrated Circuit Design
- Groundwater and Isotope Geochemistry
- Marine and coastal ecosystems
- Microwave Engineering and Waveguides
- Geology and Paleoclimatology Research
- Physiological and biochemical adaptations
- Water Quality Monitoring and Analysis
- Experimental Learning in Engineering
- Coastal and Marine Dynamics
- Fish Ecology and Management Studies
- Advanced DC-DC Converters
Alfred-Wegener-Institut Helmholtz-Zentrum für Polar- und Meeresforschung
2023-2025
University of Bremen
2025
Graz University of Technology
2021
Leibniz Institute of Freshwater Ecology and Inland Fisheries
2021
Fraunhofer Institute for Integrated Circuits
2016-2019
Abstract Seawater infiltration into the permeable sands of beach aquifers creates a high input biogeochemical reactants driven by tides and waves. The upper sand layer acts as filter, retaining particulate organic matter (POM), which is degraded bacteria under predominantly oxic conditions. seasonal variation seawater POM oxygen (O 2 ) entering zone, combined with filtration efficiency highly morphodynamic layer, determines turnover subsequent redox gradients along porewater flowpaths. We...
Subterranean estuaries are connective zones between inland aquifers and the open sea where terrestrial freshwater circulating seawater mix undergo major biogeochemical changes. They reactors that modify groundwater chemistry prior to discharge into sea. We propose subterranean of high-energy beaches particularly dynamic environments, effect boundary conditions propagates tens meters subsurface, leading strong spatio-temporal variability geochemical conditions. hypothesize they form a unique...
Animals often face changing environments, and behavioral flexibility allows them to rapidly adaptively respond abiotic factors that vary more or less regularly. However, affect prey species do not necessarily their predators. Still, the prey’s response might predator indirectly, yet evidence from wild for such a classical bottom-up effect of shaping several trophic levels remains sparse. In many aquatic daily changes in oxygen concentrations occur frequently. When drop hypoxic levels, fishes...
This paper presents linearity improvement of power amplifiers (PAs) with envelope tracking (ET) modulators. ET modulators vary the supply voltage RF to optimize efficiency, but potentially degrade system. However, has shown improve both efficiency and under certain conditions. work an analytical study PA modulation. The theoretical considerations are supported by performance measurements using hardware implementation.
High-energy beaches mark a highly variable land-ocean transition where matter fluxes are modulated by dynamic subsurface biogeochemical reactions. At the beach face, seawater infiltration into saline recirculation cell of intertidal aquifer creates high input electron acceptors and organic matter. Microorganisms rapidly degrade fresh in upper sandy layer under advective flow conditions. Filtration particulate constant supply oxygen (O2) shallow sand body result much this turnover taking...
Learning factories allow for hands-on teaching of theoretical concepts in a simulated business environment. There, the opportunities provided by digital assistance with work-flows and high value acquired process data are already an integral part offered courses, mostly as input. To improve learning experience participants taught at factories, interactive concept topics is developed. Based on existing methodologies developing workshop analytics presented. provide immersive experience, setting...
A broadband push-pull RF power amplifier (PA) is designed and implemented. The PA yields high efficiency from 0.8 to 3.7 GHz with a peak drain of 68 % at 1.6 GHz. output greater or equal 40 dBm over the entire band minimum gain 10 dB. Two 6 W packaged GaN devices are used design PA. features individual inputs optimize backoff efficiency; phase shift between its influence on overall performance investigated through simulation measurement. planar balun output. No additional matching utilized.