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Spatially explicit life cycle assessments reveal hotspots of environmental impacts from renewable electricity generation
(2022-08-30)
Renewable energy generation has great potential to reduce greenhouse gas emissions, however, it may exacerbate other environmental impacts, such as water scarcity, elsewhere in the supply chain. Here, we reveal a wide range of global environmental impacts of concentrated solar power, run-of-river hydropower, and biomass burning compared to classical coal-fired power: Spatially explicit life cycle impact assessment is used to evaluate their supply chains with respect to demand for energy, land, material, and water, ...
Aufsatz
Agile Erzählungen
(2022-01-05)
Wenn man sich mit dem Thema „Agilität“ inhaltlich befasst, erscheint es nicht angeraten, es in erster Linie als ein einheitliches theoretisches Konstrukt oder Modell zu betrachten, das man auf seine interne logische Stimmigkeit seiner einzelnen Bestandteile und auf deren empirische Verankerung hin überprüft. Damit würde man Kriterien anlegen, bei denen von vorneherein offensichtlich ist, dass der agile Ansatz dem weder gerecht werden kann noch will. Die eigentliche Bedeutung des agilen Konzepts liegt nicht in seiner ...
Aufsatz
Transmission Electron Microscopy Study on the Precipitation Behaviors of Laser-Welded Ferritic Stainless Steels and Their Implications on Intergranular Corrosion Resistance
(2022-01-04)
The intergranular corrosion susceptibility of ferritic stainless-steel weldments is strongly dependent on chromium carbide precipitation phenomena. Hence, stabilization is widely used to mitigate the aforementioned precipitation. In contrast, stabilization has proved ineffective to fully prevent intergranular corrosion due to segregation of unreacted chromium during solid-state heat-treatments. To analyze the precipitation behavior of 17 wt.-% chromium ferritic stainless steels during laser welding, sheets of ...
Aufsatz
Development of an Optical System Based on Spectral Imaging Used for a Slug Control Robot
(2022-01-14)
The state-of-the-art technique to control slug pests in agriculture is the spreading of slug pellets. This method has some downsides, because slug pellets also harm beneficials and often fail because their efficiency depends on the prevailing weather conditions. This study is part of a research project which is developing a pest control robot to monitor the field, detect slugs, and eliminate them. Robots represent a promising alternative to slug pellets. They work independent of weather conditions and can distinguish ...
Aufsatz
Rechte Radikalisierung und Deradikalisierung – Perspektiven in der psychologischen Beratung. Zum Film „Skin“ von Guy Nattiv
(2022-01-10)
Vor dem Hintergrund des Films „Skin“ von Guy Nattiv (2018) wird ein Einblick in die Dynamiken von Radikalisierungsprozessen gegeben unter Einbeziehung einer multifaktoriellen Perspektive. In einem zweiten Schwerpunkt werden die Gelingens- und Rahmenbedingungen von Deradikalisierungsprozessen erörtert. Der Beitrag schließt mit der Darstellung eines Beratungsansatzes zur Deradikalisierung.
Aufsatz
Improving Prospective Teachers’ Beliefs About a Double Discontinuity Between School Mathematics and University Mathematics
(2022-05-12)
Prospective teachers often perceive a “double discontinuity” between school mathematics and university mathematics. The first discontinuity can be described as the belief that there is no coherence between school mathematics and university mathematics, which forms part of the notoriously problematic transition from school to university. The second discontinuity can be described as a belief about the lack of relevance of university mathematics for the later professional practice of prospective teachers. Beliefs about ...
Aufsatz
Numerical simulation of viscoelastic fluid-structure interaction benchmarks and their application to the human eye
(2022-10-11)
We present a numerical solution method for time-dependent viscoelastic fluid–structure interaction employing the arbitrary Lagrangian Eulerian framework. The derived monolithic variational formulation is discretized in time using the shifted Crank–Nicolson scheme and in space using the finite element method. For the linearisation we employ Newton’s method with exact Jacobians. The viscoelastic fluid is modelled either using the Oldroyd-B or a Burgers-type model. The elastic structures are non-linear hyperelastic ...
Aufsatz
Multisite and Multitemporal Grassland Yield Estimation Using UAV-Borne Hyperspectral Data
(2022-04-26)
Grassland ecosystems can be hotspots of biodiversity and act as carbon sinks while at the same time providing the basis of forage production for ruminants in dairy and meat production. Annual grassland dry matter yield (DMY) is one of the most important agronomic parameters reflecting differences in usage intensity such as number of harvests and fertilization. Current methods for grassland DMY estimation are labor-intensive and prone to error due to small sample size. With the advent of unmanned aerial vehicles (UAVs) ...
Aufsatz
Description and prediction of copper contents in soils using different modeling approaches - Results of long-term monitoring of soils of northern Germany
(2022-10-03)
Background: Different regression approaches may be useful to predict dynamics of copper (Cu), an essential element for plants and microorganisms that becomes toxic at increased contents, in soils. //
Aim: Our objective was to explore the usefulness of mixed-effects modeling and rule-based models for a description and prediction of Cu contents in aqua regia (CuAR) in surface soils using site, pH, soil organic carbon (SOC), and the cation exchange capacity (CEC) as predictors. //
Methods: Three sites in northern ...
Aufsatz
An extendable key space integer image-cipher using 4-bit piece-wise linear cat map
(2022-09-30)
This paper presents a multiplierless image-cipher, with extendable 2048-bit key-space, based on a 4-dimensional (4D) quantized piece-wise linear cat map (PWLCM). The quantized PWLCM exhibits limit-cycles of 4-bit encoded integers with periods greater than 10⁷. The synthesis of the PWLCM in a finite state space allows to eliminate the undesirable finite precision effect due to the hardware realization. The proposed image-cipher combines chaos, modular arithmetic, and lattice-based cryptography to encrypt a color image ...