@article{SanchezWichtBaerenzung2020,
  author    = {Sanchez, Sabrina and Wicht, Johannes and B{\"a}renzung, Julien},
  title     = {Predictions of the geomagnetic secular variation based on the ensemble sequential assimilation of geomagnetic field models by dynamo simulations},
  series = {Earth, planets and space},
  volume    = {72},
  journal   = {Earth, planets and space},
  number    = {1},
  publisher = {Springer},
  address   = {New York},
  issn      = {1880-5981},
  doi       = {10.1186/s40623-020-01279-y},
  pages     = {20},
  year      = {2020},
  abstract  = {The IGRF offers an important incentive for testing algorithms predicting the Earth's magnetic field changes, known as secular variation (SV), in a 5-year range. Here, we present a SV candidate model for the 13th IGRF that stems from a sequential ensemble data assimilation approach (EnKF). The ensemble consists of a number of parallel-running 3D-dynamo simulations. The assimilated data are geomagnetic field snapshots covering the years 1840 to 2000 from the COV-OBS.x1 model and for 2001 to 2020 from the Kalmag model. A spectral covariance localization method, considering the couplings between spherical harmonics of the same equatorial symmetry and same azimuthal wave number, allows decreasing the ensemble size to about a 100 while maintaining the stability of the assimilation. The quality of 5-year predictions is tested for the past two decades. These tests show that the assimilation scheme is able to reconstruct the overall SV evolution. They also suggest that a better 5-year forecast is obtained keeping the SV constant compared to the dynamically evolving SV. However, the quality of the dynamical forecast steadily improves over the full assimilation window (180 years). We therefore propose the instantaneous SV estimate for 2020 from our assimilation as a candidate model for the IGRF-13. The ensemble approach provides uncertainty estimates, which closely match the residual differences with respect to the IGRF-13. Longer term predictions for the evolution of the main magnetic field features over a 50-year range are also presented. We observe the further decrease of the axial dipole at a mean rate of 8 nT/year as well as a deepening and broadening of the South Atlantic Anomaly. The magnetic dip poles are seen to approach an eccentric dipole configuration.},
  language  = {en}
}
@article{AlSa'diJaiserBagnichetal.2012,
  author    = {Al-Sa'di, Mahmoud and Jaiser, Frank and Bagnich, Sergey A. and Unger, Thomas and Blakesley, James C. and Wilke, Andreas and Neher, Dieter},
  title     = {Electrical and optical simulations of a polymer-based phosphorescent organic light-emitting diode with high efficiency},
  series = {Journal of polymer science : B, Polymer physics},
  volume    = {50},
  journal   = {Journal of polymer science : B, Polymer physics},
  number    = {22},
  publisher = {Wiley-Blackwell},
  address   = {Hoboken},
  issn      = {0887-6266},
  doi       = {10.1002/polb.23158},
  pages     = {1567 -- 1576},
  year      = {2012},
  abstract  = {A comprehensive numerical device simulation of the electrical and optical characteristics accompanied with experimental measurements of a new highly efficient system for polymer-based light-emitting diodes doped with phosphorescent dyes is presented. The system under investigation comprises an electron transporter attached to a polymer backbone blended with an electronically inert small molecule and an iridium-based green phosphorescent dye which serves as both emitter and hole transporter. The device simulation combines an electrical and an optical model. Based on the known highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels of all components as well as the measured electrical and optical characteristics of the devices, we model the emissive layer as an effective medium using the dye's HOMO as hole transport level and the polymer LUMO as electron transport level. By fine-tuning the injection barriers at the electron and hole-injecting contact, respectively, in simulated devices, unipolar device characteristics were fitted to the experimental data. Simulations using the so-obtained set of parameters yielded very good agreement to the measured currentvoltage, luminancevoltage characteristics, and the emission profile of entire bipolar light-emitting diodes, without additional fitting parameters. The simulation was used to gain insight into the physical processes and the mechanisms governing the efficiency of the organic light-emitting diode, including the position and extent of the recombination zone, carrier concentration profiles, and field distribution inside the device. The simulations show that the device is severely limited by hole injection, and that a reduction of the hole-injection barrier would improve the device efficiency by almost 50\%.},
  language  = {en}
}
@article{HuangRichterKleickmannetal.2022,
  author    = {Huang, Yizhen and Richter, Eric and Kleickmann, Thilo and Richter, Dirk},
  title     = {Comparing video and virtual reality as tools for fostering interest and self-efficacy in classroom management},
  series = {British journal of educational technology / British Educational Communications and Technology Agency},
  volume    = {54},
  journal   = {British journal of educational technology / British Educational Communications and Technology Agency},
  number    = {2},
  publisher = {Wiley-Blackwell},
  address   = {Oxford},
  issn      = {0007-1013},
  doi       = {10.1111/bjet.13254},
  pages     = {467 -- 488},
  year      = {2022},
  abstract  = {Video is a widely used medium in teacher training for situating student teachers in classroom scenarios. Although the emerging technology of virtual reality (VR) provides similar, and arguably more powerful, capabilities for immersing teachers in lifelike situations, its benefits and risks relative to video formats have received little attention in the research to date. The current study used a randomized pretest-posttest experimental design to examine the influence of a video- versus VR-based task on changing situational interest and self-efficacy in classroom management. Results from 49 student teachers revealed that the VR simulation led to higher increments in self-reported triggered interest and self-efficacy in classroom management, but also invoked higher extraneous cognitive load than a video viewing task. We discussed the implications of these results for pre-service teacher education and the design of VR environments for professional training purposes. Practitioner notes What is already known about this topic Video is a popular teacher training medium given its ability to display classroom situations. Virtual reality (VR) also immerses users in lifelike situations and has gained popularity in recent years. Situational interest and self-efficacy in classroom management is vital for student teachers' professional development. What this paper adds VR outperforms video in promoting student teachers' triggered interest in classroom management. Student teachers felt more efficacious in classroom management after participating in VR. VR also invoked higher extraneous cognitive load than the video. Implications for practice and/or policy VR provides an authentic teacher training environment for classroom management. The design of the VR training environment needs to ensure a low extraneous cognitive load.},
  language  = {en}
}
@article{WirthNeumannAntoniettietal.2014,
  author    = {Wirth, Jonas and Neumann, Rainer and Antonietti, Markus and Saalfrank, Peter},
  title     = {Adsorption and photocatalytic splitting of water on graphitic carbon nitride},
  series = {physical chemistry, chemical physics : PCCP},
  volume    = {2014},
  journal   = {physical chemistry, chemical physics : PCCP},
  number    = {16},
  issn      = {1463-9076},
  doi       = {10.1039/c4cp02021a},
  pages     = {15917 -- 15926},
  year      = {2014},
  abstract  = {Graphitic carbon nitride, g-C₃N₄, is a promising organic photo-catalyst for a variety of redox reactions. In order to improve its efficiency in a systematic manner, however, a fundamental understanding of the microscopic interaction between catalyst, reactants and products is crucial. Here we present a systematic study of water adsorption on g-C₃N₄ by means of density functional theory and the density functional based tight-binding method as a prerequisite for understanding photocatalytic water splitting. We then analyze this prototypical redox reaction on the basis of a thermodynamic model providing an estimate of the overpotential for both water oxidation and H⁺ reduction. While the latter is found to occur readily upon irradiation with visible light, we derive a prohibitive overpotential of 1.56 eV for the water oxidation half reaction, comparing well with the experimental finding that in contrast to H₂ production O₂ evolution is only possible in the presence of oxidation cocatalysts.},
  language  = {en}
}