cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.35097/1307
title: Numerical experiments to "Inverse medium scattering for a nonlinear Helmholtz equation"

description: This is a guide to generate the figures that have been used in the work &gt; Inverse medium scattering for a nonlinear Helmholtz equation by Roland Griesmaier, Marvin Knöller and Rainer Mandel. You find all needed Matlab files to generate the figures. An overview: -evaluategfun_z is supposed to generate the Herglotz density g, dependent on a possible shift z\\in R^2 -Finalplots plots the figures at the end of the computation -funhandle_zAbs evaluates the function handle corresponding to the factorization method -funhanlde_zReal evaluates the function handle corresponding to the monotonicity method -getc and ToepPhi are used to evaluate the Toeplitz matrix in order to evaluate the 2d convolution from the nonlinear Lippmann Schwinger equation. Convolution is performed by using the 2d Fourier transform. -getUi_z generates incoming Herglotz fields, dependent on a possible shift z\\in R^2 -mycon is the constraint used in the optimization -NLHH evaluates the far field given an incoming field. This function uses a fixed point iteration arising from the nonlinear Lippmann Schwinger equation. -nonlinear_qh2_scaled gives the (scaled) function handle corresponding to a kite made of fused silica. The scripts Numerical_Example_Fac.m and Numerical_Example_Mon.m start the reconstruction of the kite using the factorization and the monotonicity method, respectively. The computations have been carried out on a Cluster using 32 Cores. Generating an example from scratch takes approximately 4 days. Computations have been carried out using the Matlab 2018a version. The code uses parallelization from the Matlab Parallelization Toolbox. The code uses optimization from the Matlab Optimization Toolbox.
DOI: 10.35097/1349
title: Numerical experiments to "High-frequency wave-propagation: error analysis for analytical and numerical approximations"

description: This code has been used for the numerical experiments in the thesis "High-frequency wave-propagation: error analysis for analytical and numerical approximations" by Julian Baumstark, see https://www.doi.org/10.5445/IR/1000149719.
description: The scripts are intended to reproduce the figures from the thesis "High-frequency wave-propagation: error analysis for analytical and numerical approximations" by Julian Baumstark ################################################################################ #### Requirements The codes are tested on Ubuntu 18.04 LTS with Matlab R2020a ################################################################################ #### Generation of figures With this code Figures 3.1, 3.2, 4.1, 4.2, 4.3, 5.1, and 5.2 can be generated. The calculation of the data for Figure 4.1, 4.2, 4.3, 5.1 and 5.2 takes a few days and requires a storage space of about 140 GB. #### Figure 3.1 and 3.2 In order to obtain Figure 3.X (X=1 or 2) run the command visualize_Fig3X.m in Matlab. #### Figure 4.1, 4.2 and 4.3 Open folder "Chapter_4" in Matlab. In order to obtain Figure 4.X (X=1 or 2 or 3) first run the command kleingordon_analytical_approx.m to compute the data. Then, run visualize_Fig4X.m in Matlab. #### Figure 5.1 and 5.2 Open folder "Chapter_5" in Matlab. In order to obtain Figure 5.X (X=1 or 2) first run the command kleingordon_numerical_approx.m to compute the data. Then, run visualize_Fig5X.m in Matlab.
DOI: 10.35097/1351
title: Numerical experiments to "Maximizing the electromagnetic chirality of thin metallic nanowires at optical frequencies"

description: For generating the numerical examples 1-3, run Paper_Ex1 Paper_Ex2 and Paper_Ex3. For the third example, we further provide the samples that we used in our publication. Consider the remarks in Paper_Ex3 for re-simulating them.
DOI: 10.35097/1287
title: Numerical experiments to "On averaged exponential integrators for semilinear wave equations with solutions of low-regularity"

description: This code was used for the numerical experiments in the preprint (CRC Preprint 2021/12; URL: https://www.waves.kit.edu/downloads/CRC1173_Preprint_2021-12.pdf) and in the paper "On averaged exponential integrators for semilinear wave equations with solutions of low-regularity" by S. Buchholz, B. Dörich, and M. Hochbruck.
description: This program is intended to reproduce the results from the paper "On averaged exponential integrators for semilinear wave equations with solutions of low-regularity. " by S. Buchholz, B. Dörich, and M. Hochbruck. The codes generates Figure 2. #### Requirements The program is tested with 1) Ubuntu 16.04.7 LTS and Python 3.7.6 and the following version of its modules: - numpy - 1.15.4 - scipy - 1.4.1 - matplotlib - 3.2.1 - tikzplotlib - 0.9.6 2) Ubuntu 18.04.5 LTS and Python 3.6.9 and the following version of its modules: - numpy - 1.19.2 - scipy - 1.5.1 - matplotlib - 3.3.2 - tikzplotlib - 0.9.4 #### Figure 2 In this folder open a console and run the following commands after each other. 1) Run "python3 run_paper_Strang_N_2pw09.py" 2) Run "python3 run_paper_Strang_N_2pw10.py" 3) Run "python3 run_paper_Strang_N_2pw11.py" After running the calculations, the errors can be found in the folder "results" as tikz-files.
DOI: 10.35097/1334
title: Numerical experiments to "On leapfrog-Chebyshev schemes for second-order differential equations"

description: This code has been used for the numerical experiments in the thesis "On leapfrog-Chebyshev schemes for second-order differential equations" by Constantin Carle; see https://www.doi.org/10.5445/IR/1000147725.
description: The computations are done with Python3. ##### Requirements The code is tested on Ubuntu 20.04.4 LTS with Python 3.8.10 and the following versions of its modules numpy - 1.17.4 scipy - 1.3.3 h5py - 2.10.0 dolfin (fenics) - 2019.2.0.dev0 (including mshr) matplotlib - 3.1.2 tikzplotlib - 0.9.6 (only for generating tikz/pgfplots files) ##### Generation of figures Figures **4.6, 4.7, 4.8, 4.9, 4.10, 5.3, 5.4, 5.5, 5.7 (including 5.6)**, and **5.8** can be generated with this code. In order to obtain Figure X.Y either - execute the Python script **script_Figure-XpY.py** in a suitable integrated development environment or - run the command **python3 script_Figure-XpY.py** in a terminal session. The scripts for Figures 4.6, 4.8, 4.10, and 5.5 only produce half of the figures. To get the other half, open the script and set the Boolean variable at the beginning of the script from `True` to `False` (case sensitive). - Figure 4.6: Boolean variable `LFC_unstab` + `True` : Figures 4.6 (a), (c), (e), (g) + `False`: Figures 4.6 (b), (d), (f), (h) - Figure 4.8: Boolean variable `stepsize_small` + `True` : Figures 4.8 (a), (b) + `False`: Figures 4.8 (c), (d) - Figure 4.10: Boolean variable `LFCpol_to_G` + `True` : Figures 4.10 (a), (b), (c) + `False`: Figures 4.10 (d), (e), (f) - Figure 5.5: Boolean variable `stepsize_small` + `True` : Figures 5.5 (a) + `False`: Figures 5.5 (b) Instead of the plots you can get the tikz/pgfplots files which were used for the figures in the thesis by setting the Boolean variable `plot_figure` from `True` to `False` in the scripts.
DOI: 10.35097/1299
title: Numerical experiments to "Rank-adaptive dynamical low-rank integrators for first-order and second-order matrix differential equations"

description: Instructions: The scripts inside the subfolders are intended to reproduce the figures from the preprint &gt; Rank-adaptive dynamical low-rank integrators for first-order and second-order matrix differential equations by Marlis Hochbruck, Markus Neher, and Stefan Schrammer Requirements The codes are tested with Ubuntu 20.04.2 LTS and Python 3.8.5 and the following version of its modules: numpy 1.19.2 scipy 1.5.2 numba 0.51.2 colorama 0.4.4 h5py 2.10.0 matplotlib 3.3.2 tikzplotlib 0.9.6 Generation of figures (tikz files containing the data are also created) In the folder fracginz open a console and run the commands 1. to create the data for Figures (1) and (2) python3 fgl.py 2. to create Figures (1) and (2) python3 fgl_results.py In the folder fracschr open a console and run the commands 3. to create the data for Figure (3) python3 fsr.py 4. to create Figure (3) python3 fsr_results.py In the folder laserplasma open a console and run the commands 5. to create the data for Figures (4) and (5) python3 lpi.py 6. to create Figures (4) and (5) python3 lpi_globalerr.py python3 lpi_svals_maxint.py In the folder sineg open a console and run the commands 7. to create the data for Figures (6) and (7) python3 sineg.py 8. to create Figures (6) and (7) python3 sineg_globalerr_ranks.py If the reference solutions shall be recomputed, uncomment the line methods.append(...) at the beginning of the scripts fgl.py, fsr.py, lpi.py, and sineg.py, respectively.
DOI: 10.35097/1285
title: Numerical experiments to the dissertation "A unified error analysis for the numerical solution of nonlinear wave-type equations with application to kinetic boundary conditions"

description: This code is used for the numerical experiments in the dissertation "A unified error analysis for the numerical solution of nonlinear wave-type equations with application to kinetic boundary conditions" by Jan Leibold (cf. Section 6.5)
description: The computations are done in C++ using the Finite Element library deal.II; the plots from the dissertation then are generated with Matlab. To use this code, deal.II (release 9.2.0) has to be installed, cf. https://www.dealii.org/9.2.0 In order to compile the program, open a terminal session in this folder and call "cmake -DDEAL_II_DIR=/path/to/deal.II .". Next, call "make release" and then "make" to compile the files. Before running the program, specify in the 'config.ini' for which figures the calculations should be performed. By default, the calculations for all plots are performed. Finally, run the program with "make run". This performs the computations and generates files in the "output" folder containing the results of the numerical experiments. After that, the plots can be generated with the Matlab Script 'plot_figures.m'. In this file it can also be selected which plots should be generated.
DOI: 10.35097/1552
title: Our (in)Secure Web: Understanding Update Behavior of Websites and Its Impact on Security

description: Software updates take an essential role in keeping IT environments secure. If service providers delay or do not install updates, it can cause unwanted security implications for their environments. This paper conducts a large-scale measurement study of the update behavior of websites and their utilized software stacks. Across 18 months, we analyze over 5.6M websites and 246 distinct client- and server-side software distributions. We found that almost all analyzed sites use outdated software.
description: This dataset holds additional materials to the paper "Our (in)Secure Web: Understanding Update Behavior of Websites and Its Impact on Security".
DOI: 10.35097/1317
title: PRESLHY Experiment series 3.1, part B

description: In the work package WP3.1 of the PRESLHY project the blow-down behavior of cryogenic hydrogen stored at elevated pressure is investigated by the project partners Karlsruhe Institute of Technology (KIT) and Pro-Science (PS). The main purpose of WP3.1 was to provide validation or reference data for • models defining or using a discharge coefficient, • subsequent explosion tests, where the released gases will be ignited (see E5.2), and • electrostatic field excitation and associated ignition potential of high-pressure hydrogen gas jets at cryogenic temperatures.
description: In part B of WP3.1 of the PRESLHY project 12 hydrogen blow-down experiments were performed with the Cryostat-facility on a free field-test site located a few kilometers to the north of KIT Campus North. About half of the experiments were made with liquid hydrogen at cryogenic temperatures (approx. 20 K). In the experimental campaign, the same release branch as in the related DisCha-experiments of Task 3.1A was used to facilitate comparison with the experiments of this series. For the same reason, five of the blow-down tests were made under ambient temperature conditions, since in part A also half of the matrix was performed under these conditions. The tests showed very good reproducibility. Besides the discharge characteristics and the transient jet behavior also the electrostatic fields have been recorded to understand potential mechanisms for spontaneous ignition.
DOI: 10.35097/1319
title: PRESLHY Experiment series 3.4

description: In the frame WP3.4 of the PRESLHY project 10 experiments on LH2-pool formation above different substrates have been performed with the POOL-facility on a free field-test site located a few kilometers to the north of KIT Campus North. Substrates to be investigated comprised concrete, sand, water and gravel. Four of the experiments were made with artificial side wind of known direction and known velocity to investigate the influence of side wind on the formation and evaporation of the LH2-pools.
description: In the frame WP3.4 of the PRESLHY project 10 experiments on LH2-pool formation above different substrates have been performed with the POOL-facility on a free field-test site located a few kilometers to the north of KIT Campus North. Substrates to be investigated comprised concrete, sand, water and gravel. Four of the experiments were made with artificial side wind of known direction and known velocity to investigate the influence of side wind on the formation and evaporation of the LH2-pools.
description: The POOL-facility was controlled via a computer that was located in a tent in a distance of approx. 10 m behind the wall with the BOS-background pattern, but after the initiation of an experiment this computer was controlled remotely from a shelter in a distance of approx. 100 m to the facility The control computer was also used to display and save all sensor records (temperatures, H2-concentrations, ambient wind conditions) with a measuring frequency of 10 Hz via LabView. The POOL-facility itself mainly consists of a stainless-steel box (dimensions 0.5 x 0.5 x 0.2 m³) that is filled up to half the height (0.1 m) with different substrates that can be found in, or are feasible for various real LH2-applications. The substrates used in the tests were concrete, sand, water and gravel, with the concrete pool being prepared already more than 1 month prior to the first experiment to allow sufficient hardening and drying. Three boxes were fabricated for the experiments, so one of these boxes had to be used for the experiments with two substrates (water and gravel, gravel was kept in separate box when not used, so in all experiments with gravel the same stones were used as substrate). For thermal protection the outside of the boxes was insulated by Styrofoam plates on its ground face and the sides. Inside the substrate layer 8 thermocouples were positioned via holders prior to the filling of the box with the respective substrate. The substrate filled box was then positioned on a scale on a table and the super insulated hose from the LH2-trailer was then fixed to a rack on the top of the table that positioned its open end above the box.
DOI: 10.35097/1321
title: PRESLHY Experiment series 4.4; Material of the ground: concrete

description: To identify and understand the ignition risks associated with situations unique to liquid hydrogen releases, where factors of cryogenic temperatures are significant. Ares of particular interest are: ignition potential at reduced temperature in the vapour phase; electrostatic charging in liquefied/multiphase mixtures; and energetic multiphase mixtures of hydrogen and oxygen. The key objective is to understand the impact of these particular circumstances on the likelihood of ignition, and to confirm the prioritisation of phenomena for further study within the project. Phenomena: Ignition above the pool under variable conditions (material of the ground, initial temperature).
description: To identify and understand the ignition risks associated with situations unique to liquid hydrogen releases, where factors of cryogenic temperatures are significant. Ares of particular interest are: ignition potential at reduced temperature in the vapour phase; electrostatic charging in liquefied/multiphase mixtures; and energetic multiphase mixtures of hydrogen and oxygen. The key objective is to understand the impact of these particular circumstances on the likelihood of ignition, and to confirm the prioritisation of phenomena for further study within the project. Phenomena: Ignition above the pool under variable conditions (material of the ground, initial temperature).
description: The POOL-facility mainly consists of an insulated stainless-steel box with the dimensions 0.5 x 0.5 x 0.2 m³ that is filled up to half the height (0.1 m) with the respective substrate. The height of the LH2-pool that forms above the substrate can be determined using the weight of the complete facility, since it is positioned on a scale, but also 6 thermocouples that are located in different heights above the pool. Ignition point height varies from 8cm to 45cm.
DOI: 10.35097/1323
title: PRESLHY Experiment series 4.4; Material of the ground: gravel

description: To identify and understand the ignition risks associated with situations unique to liquid hydrogen releases, where factors of cryogenic temperatures are significant. Ares of particular interest are: ignition potential at reduced temperature in the vapour phase; electrostatic charging in liquefied/multiphase mixtures; and energetic multiphase mixtures of hydrogen and oxygen. The key objective is to understand the impact of these particular circumstances on the likelihood of ignition, and to confirm the prioritisation of phenomena for further study within the project. Phenomena: Ignition above the pool under variable conditions (material of the ground, initial temperature).
description: To identify and understand the ignition risks associated with situations unique to liquid hydrogen releases, where factors of cryogenic temperatures are significant. Ares of particular interest are: ignition potential at reduced temperature in the vapour phase; electrostatic charging in liquefied/multiphase mixtures; and energetic multiphase mixtures of hydrogen and oxygen. The key objective is to understand the impact of these particular circumstances on the likelihood of ignition, and to confirm the prioritisation of phenomena for further study within the project. Phenomena: Ignition above the pool under variable conditions (material of the ground, initial temperature).
description: The POOL-facility mainly consists of an insulated stainless-steel box with the dimensions 0.5 x 0.5 x 0.2 m³ that is filled up to half the height (0.1 m) with the respective substrate. The height of the LH2-pool that forms above the substrate can be determined using the weight of the complete facility, since it is positioned on a scale, but also 6 thermocouples that are located in different heights above the pool. Ignition point height varies from 8cm to 45cm.
DOI: 10.35097/1320
title: PRESLHY Experiment series 4.4; Material of the ground: sand

description: To identify and understand the ignition risks associated with situations unique to liquid hydrogen releases, where factors of cryogenic temperatures are significant. Ares of particular interest are: ignition potential at reduced temperature in the vapour phase; electrostatic charging in liquefied/multiphase mixtures; and energetic multiphase mixtures of hydrogen and oxygen. The key objective is to understand the impact of these particular circumstances on the likelihood of ignition, and to confirm the prioritisation of phenomena for further study within the project. Phenomena: Ignition above the pool under variable conditions (material of the ground, initial temperature).
description: To identify and understand the ignition risks associated with situations unique to liquid hydrogen releases, where factors of cryogenic temperatures are significant. Ares of particular interest are: ignition potential at reduced temperature in the vapour phase; electrostatic charging in liquefied/multiphase mixtures; and energetic multiphase mixtures of hydrogen and oxygen. The key objective is to understand the impact of these particular circumstances on the likelihood of ignition, and to confirm the prioritisation of phenomena for further study within the project. Phenomena: Ignition above the pool under variable conditions (material of the ground, initial temperature).
description: The POOL-facility mainly consists of an insulated stainless-steel box with the dimensions 0.5 x 0.5 x 0.2 m³ that is filled up to half the height (0.1 m) with the respective substrate. The height of the LH2-pool that forms above the substrate can be determined using the weight of the complete facility, since it is positioned on a scale, but also 6 thermocouples that are located in different heights above the pool. Ignition point height varies from 8cm to 45cm.
DOI: 10.35097/1322
title: PRESLHY Experiment series 4.4; Material of the ground: water

description: To identify and understand the ignition risks associated with situations unique to liquid hydrogen releases, where factors of cryogenic temperatures are significant. Ares of particular interest are: ignition potential at reduced temperature in the vapour phase; electrostatic charging in liquefied/multiphase mixtures; and energetic multiphase mixtures of hydrogen and oxygen. The key objective is to understand the impact of these particular circumstances on the likelihood of ignition, and to confirm the prioritisation of phenomena for further study within the project. Phenomena: Ignition above the pool under variable conditions (material of the ground, initial temperature).
description: To identify and understand the ignition risks associated with situations unique to liquid hydrogen releases, where factors of cryogenic temperatures are significant. Ares of particular interest are: ignition potential at reduced temperature in the vapour phase; electrostatic charging in liquefied/multiphase mixtures; and energetic multiphase mixtures of hydrogen and oxygen. The key objective is to understand the impact of these particular circumstances on the likelihood of ignition, and to confirm the prioritisation of phenomena for further study within the project. Phenomena: Ignition above the pool under variable conditions (material of the ground, initial temperature).
description: The POOL-facility mainly consists of an insulated stainless-steel box with the dimensions 0.5 x 0.5 x 0.2 m³ that is filled up to half the height (0.1 m) with the respective substrate. The height of the LH2-pool that forms above the substrate can be determined using the weight of the complete facility, since it is positioned on a scale, but also 6 thermocouples that are located in different heights above the pool. Ignition point height varies from 8cm to 45cm.
DOI: 10.35097/1561
title: PRESLHY Experiment series 5.1

description: The objectives of this work are to complete the experimental database on cryogenic LH2 combustion, including laminar steady state and turbulent combustion and detonation of LH2 and gaseous hydrogen in air at ambient and cryogenic temperatures. The major characteristics to be investigated was the pressure, temperature, heat flux, and dynamics of the processes. Effects of scale and turbulence also was considered as parameters of the processes. Similar to LH2 distribution the combustion analysis included confinement geometry and obstructions.
description: The presented data and video files were obtained during experiments within the WP5.1., characterizing the LH2 jet fire behavior, including scaling and radiation properties ( variations on heat flux and dosis, temperature, max pressure and rise rate) at various initial properties (initial pressure, nozzle diameter, ignition location, ignition delay times)