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Agro-ecological landuse transformation in oasis systems of Al Jabal Al Akhdar, northern Oman
(2021-04-08)
The millenia-old oasis systems in the Western Hajar Mountains of Northern Oman have received widespread attention as models of sustainable irrigated agriculture in hyperarid Arabia. Given Oman’s rampant urbanization, growing scarcity of water and skilled labour, we quantified chances in water use, land use, and land cover between 2007 and 2018 using a rare time-series approach of detailed GIS-based crop mapping. Results from satellite image analysis and comprehensive ground truthing showed that urban areas grew from ...
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Evidence of considerable C and N transfer from peas to cereals via direct root contact but not via mycorrhiza
(2021-06-01)
Intercropping of legumes and cereals is an important management method for improving yield stability, especially in organic farming systems. However, knowledge is restricted on the relevance of different nutrient transfer pathways. The objective of the study was to quantify nitrogen (N) and carbon (C) transfer from peas to triticale by (1) direct root contact (= R), (2) arbuscular mycorrhizal fungi (AMF; = A), and (3) diffusion (= D). Pea (Pisum sativum cv. Frisson and P2) and triticale (Triticum × Secale cv. Benetto) ...
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Single-atom heat engine as a sensitive thermal probe
(2020-09-09)
We propose employing a quantum heat engine as a sensitive probe for thermal baths. In particular, we study a single-atom Otto engine operating in an open thermodynamic cycle. Owing to its cyclic nature, the engine is capable of translating small temperature differences between two baths into a macroscopic oscillation in a flywheel. We present analytical and numerical modeling of the quantum dynamics of the engine and estimate it to be capable of detecting temperature differences as small as 2 μK. This sensitivity can ...
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Microstructural and mechanical properties of dissimilar nitinol and stainless steel wire joints produced by micro electron beam welding without filler material
(2020-09-18)
Nitinol is a shape memory and superelastic alloy, respectively, and stainless steels are widely used materials in medical engineering, e.g., for implants and medical instruments. However, due to its high price and poor machinability, there is a high demand for dissimilar welding of nitinol components to stainless steel. During welding of titanium-containing alloys, like nitinol, to ferrous metals like stainless steel, intermetallic phases between titanium and iron may form. These phases are brittle and lead to rapid ...
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Deutungen von Bildung frühpädagogischer Fachkräfte
(2021-08-20)
Kindertageseinrichtungen gelten als Bildungsinstitutionen und leisten einen wesentlichen Beitrag zur Gestaltung des Aufwachsens von Kindern in Deutschland. Dabei spielen die frühpädagogischen Fachkräfte als Gestalter_innen und Ermöglicher_innen von Bildungsprozessen für Kinder eine entscheidende Rolle. Der Beitrag nimmt ihre Vorstellungen von Bildung und worauf sich diese gründen in den Blick.
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Detecting Careless Responding in Survey Data Using Stochastic Gradient Boosting
(2021-04-19)
Careless responding is a bias in survey responses that disregards the actual item content, constituting a threat to the factor structure, reliability, and validity of psychological measurements. Different approaches have been proposed to detect aberrant responses such as probing questions that directly assess test-taking behavior (e.g., bogus items), auxiliary or paradata (e.g., response times), or data-driven statistical techniques (e.g., Mahalanobis distance). In the present study, gradient boosted trees, a ...
Aufsatz
Vibrotaktile Codierung von Standardfunktionen einer Menüführung
(2020-03-03)
Tactons sind taktile Nachrichten, die dem Nutzer Informationen über den haptischen Sinneskanal übermitteln, und können beispielsweise bei der Interaktion mit Touchscreens von Nutzen sein. In dieser Studie wird die systematische Erarbeitung eines Tacton-Sets für Standardfunktionen einer Menüführung (im Einzelnen die Funktionen Beenden, Bestätigen, Hauptmenü, Hilfe, Korrektur, Lauter, Leiser sowie Zurück) vorgestellt. Neben existierenden Erkenntnissen aus der Literatur wurden bei der Gestaltung des Tacton-Sets ebenfalls ...
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Improving Animal Health on Organic Dairy Farms: Stakeholder Views on Policy Options
(2020-04-09)
Although ensuring good animal health is a stated aim of organic livestock farming and an important reason why consumers purchase organic products, the health states actually achieved are comparable to those in conventional farming. Unfortunately, there have been no studies to date that have assessed stakeholder views on different policy options for improving animal health on organic dairy farms. To address this deficit, stakeholder consultations were conducted in four European countries, involving 39 supply-chain ...
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Durability Properties of Ultra-High Performance Lightweight Concrete (UHPLC) with Expanded Glass
(2021-10-05)
It is important to ensure the durability and safety of structures. In the case of newly developed materials that are outside the current rules, it is important to investigate all aspects of structural safety. The material studied in the following is a structural lightweight concrete with an ultra-high-performance matrix and expanded glass as a lightweight aggregate. The material, with a compressive strength of 60–100 MPa and a bulk density of 1.5–1.9 kg/dm³, showed high capillary porosities of 12 vol% (ultra-high-performance ...
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Developing and publishing strong empirical research in sustainability management - adressing the intersection of theory, method, and empirical field
(2021-02-05)
Students starting their research into sustainability management are often driven by a normative assumption of wanting “to do something good” or “save the world” from this or that problem. This also holds for many researchers, where the pressure to do research that has an immediate impact on the local business or natural environment is paramount. This often gets into the way of developing sound research that might pass the review process in strong academic journals. Good (empirical) research builds on the interplay ...