Coding da Vinci Niedersachsen 2020 - Projektbericht

Mit der Preisverleihung am 29. Januar 2021 endete Coding da Vinci Niedersachsen 2020. Der Abschlussbericht zum Projekt bietet einen ausführliche Rückblick auf den Kultur-Hackathon „Coding da Vinci Niedersachsen 2020“ und eine Zusammenfassung der Ergebnisse

On the role of the Helmholtz-Leray projector in the space discretization of the Navier-Stokes equations

Recent progress on pressure-robust mixed methods for the incompressible Navier-Stokes equations and the connection to the Helmholtz-Leray projector is presented. It is argued that and how pressure-robust methods allow to decrease the ( formal ) approximation order of the used discretizations. As applications, electrolytes and stagnation point flows are emphasized

Modeling and simulation of electrically driven quantum light emitters

The design of electrically driven quantum light sources based on semiconductor quantum dots, such as single-photon emitters and nanolasers, asks for modeling approaches combining classical device physics with cavity quantum electrodynamics . In particular, one has to connect the well-established fields of semi-classical semiconductor transport theory and the theory of open quantum systems . We present a first step in this direction by coupling the van Roosbroeck system with a quantum master equation in Lindblad form . The resulting hybrid quantum-classical system obeys the fundamental laws of non-equilibrium thermodynamics and provides a comprehensive description of quantum dot devices on multiple scales : It enables the calculation of quantum optical figures of merit (e.g. the second order intensity correlation function) together with the spatially resolved simulation of the current flow in realistic semiconductor device geometries in a unified way

High resolution Magnetic Resonance Imaging experiments - lessons in nonlinear statistical modeling

Recent advances in neuro-imaging attempt to enable in-vivo histology of the brain. Doing so requires increased spatial resolution up to a situation where the signal meets the noise floor. The talk will cover research conducted at WIAS, in collaboration with MR physicists, on statistical issues in modeling imaging data characterized by low signal-to-noise ratio (SNR). I'll cover several specific, but interrelated problems: - characterization of the signal distribution in MR experiments, - effects of preprocessing on the signal distribution, - estimation of the noise profile in MR images, - use of spatial information for variance reduction in (collections of) MR images, - bias due to incorrect modeling in MR experiments. I'll consider two specific imaging experiments to illustrate problems, characterize effects that are due to high measurment noise and provide solutions for: - diffusion weighted MR, with an analysis based on data of the Human Connectome Project, - multi-parameter mapping, using data measured at the Wellcome Trust Center for Neuroimaging, London. Literature: S. Becker, K. Tabelow, S. Mohammadi, N. Weiskopf and J. Polzehl, Adaptive smoothing of multi-shell diffusion-weighted MR data by msPOAS, NeuroImage, 95 (2014) pp. 90--105. K. Tabelow, H.U. Voss and J. Polzehl, Local estimation of the noise level in MRI using structural adaptation, Medical Image Analysis, 20 (2015) pp. 76--86. J. Polzehl and K. Tabelow, Low SNR in dMRI models, JASA, 11 (2016) pp. 1480--1490. K. Tabelow, Ch. D'Alonzo, L. Ruthotto, M. F. Callaghan, N. Weiskopf, J. Polzehl and S. Mohammadi, Removing the estimation bias due to the noise floor in multi-parameter maps, ISMRM annual meeting 2017

A benchmark study for CFD solvers: simulation of air flow in livestock husbandry

In this work we present the results of a joint effort of three Leibniz Institutes (ATP, TROPOS and WIAS) leading to the validation of numerical methods and software for fluid simulations. The benchmark problem is motivated by the application in livestock husbandry, in which the understanding flow characteristics is of extreme importance in order to guarantee good quality fresh air and being environmentally sparing.In this field, CFD represents a valuable tool that enable simulation of flow patterns in different configurations . In order to assess the performance of different CFD approaches (including different solver, flow models and numerical methods ) three open source models are compared: ASAM (developed at TROPOS), OpenFOAM and ParMooN (developed at WIAS). The results are compared with measurements obtained by wind tunnel experiments

Handling research software: recommendations to users, developers and research managers

A working group initiated by a joint initiative of German research and funding organizations developed a "helping hand" paper providing recommendations on important aspects of research software developmement and maintenance [1]. It is addressed to the different stakeholders in the hierarchy of an research organization. The talk will introduce the main points of this document. Based on the personal experience of the speaker a number of steps necessary to introduce these guidelines into the everyday practice of a research institution will be discussed. [1] Katerbow, Matthias / Feulner, Georg (2018): Handreichung zum Umgang mit Forschungssoftware. Herausgegeben von der AG Forschungssoftware im Rahmen der Schwerpunktinitiative Digitale Information der Allianz der deutschen Wissenschaftsorganisationen. Unter Mitarbeit von Mathias Bornschein, Björn Brembs, Michael Erben-Russ, Konrad Förstner, Michael Franke, Bernadette Fritzsch, Jürgen Fuhrmann, Michael Goedicke, Stephan Janosch, Uwe Konrad, Dennis Zielke

Der Umgang mit Forschungsdaten an der Leibniz Universität Hannover. Auswertung einer Umfrage und ergänzender Interviews 2015/16

Im Kontext des Projekts „Entwicklung eines institutionellen Konzepts zum Forschungsdatenmanagement an der Leibniz Universität Hannover“ wurden 2015/16 eine universitätsinterne Online-Umfrage und ergänzende Interviews durchgeführt. Deren Ergebnisse ermöglichen einen Einblick in den derzeitigen Umgang mit Forschungsdaten und eine Abschätzung des Bedarfs an Beratung, Schulung und technischer Infrastruktur seitens des wissenschaftlichen Personals. In diesem Bericht werden die Daten präsentiert und ausgewertet

FAQs zu rechtlichen Aspekten im Umgang mit Forschungsdaten

In diesem Merkblatt sind häufige Fragen von Forschenden sowie Antworten von Juristinnen und Juristen der Leibniz Universität Hannover und der Technischen Informationsbibliothek zu rechtlichen Aspekten im Umgang mit Forschungsdaten zusammengestellt. Ein Großteil der Informationen sollte auch auf andere Forschungseinrichtungen übertragbar sein. Die hier zusammengestellten Informationen sind nur als grobe Orientierungshilfe anzusehen, die eine individuelle Rechtsberatung nicht ersetzen kann. Alle Angaben sind ohne Gewähr

Universitaetsbibliothek Hannover und Technische Informationsbibliothek. Jahresbericht 1986

SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

Universitaetsbibliothek und Technische Informationsbibliothek Hannover. Jahresbericht 1988

SIGLECopy held by FIZ Karlsruhe; available from UB/TIB Hannover / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman