--- _id: '24159' abstract: - lang: eng text: "The online fitting of a microscopic traffic simulation model to reconstruct the current state of a real traffic\r\narea can be challenging depending on the provided data. This paper presents a novel method based on limited\r\ndata from sensors positioned at specific locations and guarantees a general accordance of reality and\r\nsimulation in terms of multimodal road traffic counts and vehicle speeds. In these considerations, the actual\r\npurpose of research is of particular importance. Here, the research aims at improving the traffic flow by\r\ncontrolling the Traffic Light Systems (TLS) of the examined area which is why the current traffic state and\r\nthe route choices of individual road users are the matter of interest. An integer optimization problem is derived\r\nto fit the current simulation to the latest field measurements. The concept can be transferred to any road traffic\r\nnetwork and results in an observation of the current multimodal traffic state matching at the given sensor\r\nposition. First case studies show promosing results in terms of deviations between reality and simulation." author: - first_name: Kevin full_name: Malena, Kevin id: '36303' last_name: Malena orcid: 0000-0003-1183-4679 - first_name: Christopher full_name: Link, Christopher id: '38249' last_name: Link - first_name: Sven full_name: Mertin, Sven id: '13195' last_name: Mertin - first_name: Sandra full_name: Gausemeier, Sandra id: '17793' last_name: Gausemeier - first_name: Ansgar full_name: Trächtler, Ansgar id: '552' last_name: Trächtler citation: ama: 'Malena K, Link C, Mertin S, Gausemeier S, Trächtler A. Online State Estimation for Microscopic Traffic Simulations using Multiple Data Sources*. In: VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems. Vol 7. VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems. SCITEPRESS; 2021:386-395.' apa: Malena, K., Link, C., Mertin, S., Gausemeier, S., & Trächtler, A. (2021). Online State Estimation for Microscopic Traffic Simulations using Multiple Data Sources*. VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems, 7, 386–395. bibtex: '@inproceedings{Malena_Link_Mertin_Gausemeier_Trächtler_2021, place={Portugal}, series={VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems}, title={Online State Estimation for Microscopic Traffic Simulations using Multiple Data Sources*}, volume={7}, booktitle={VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems}, publisher={SCITEPRESS}, author={Malena, Kevin and Link, Christopher and Mertin, Sven and Gausemeier, Sandra and Trächtler, Ansgar}, year={2021}, pages={386–395}, collection={VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems} }' chicago: 'Malena, Kevin, Christopher Link, Sven Mertin, Sandra Gausemeier, and Ansgar Trächtler. “Online State Estimation for Microscopic Traffic Simulations Using Multiple Data Sources*.” In VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems, 7:386–95. VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems. Portugal: SCITEPRESS, 2021.' ieee: K. Malena, C. Link, S. Mertin, S. Gausemeier, and A. Trächtler, “Online State Estimation for Microscopic Traffic Simulations using Multiple Data Sources*,” in VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems, Online Streaming, 2021, vol. 7, pp. 386–395. mla: Malena, Kevin, et al. “Online State Estimation for Microscopic Traffic Simulations Using Multiple Data Sources*.” VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems, vol. 7, SCITEPRESS, 2021, pp. 386–95. short: 'K. Malena, C. Link, S. Mertin, S. Gausemeier, A. Trächtler, in: VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems, SCITEPRESS, Portugal, 2021, pp. 386–395.' conference: end_date: 2021-04-30 location: Online Streaming name: 7th International Conference on Vehicle Technology and Intelligent Transport Systems start_date: 2021-04-28 date_created: 2021-09-10T12:19:14Z date_updated: 2026-01-26T08:49:53Z department: - _id: '153' intvolume: ' 7' keyword: - Microscopic Traffic Simulation - Online State Estimation - Mixed Road Users - Sensor Fusion - Integer Programming - Route Choice - Vehicle2Infrastructure language: - iso: eng main_file_link: - url: https://www.scitepress.org/PublicationsDetail.aspx?ID=3xZWfOSENWk=&t=1 page: 386-395 place: Portugal project: - _id: '688' name: Pilotprojekt "Schlosskreuzung" publication: VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems publication_identifier: isbn: - 978-989-758-513-5 publication_status: published publisher: SCITEPRESS quality_controlled: '1' related_material: link: - relation: confirmation url: https://www.scitepress.org/PublicationsDetail.aspx?ID=3xZWfOSENWk=&t=1 record: - id: '33849' relation: is_continued_by status: public series_title: VEHITS 2021 Proceedings of the 7th International Conference on Vehicle Technology and Intelligent Transport Systems status: public title: Online State Estimation for Microscopic Traffic Simulations using Multiple Data Sources* type: conference user_id: '36303' volume: 7 year: '2021' ... --- _id: '29940' abstract: - lang: eng text: A full-bridge modular multilevel converter (MMC) is compared to a half-bridge-based MMC for high-current low-voltage DC-applications such as electrolysis, arc welding or datacenters with DC-power distribution. Usually, modular multilevel converters are used in high-voltage DC-applications (HVDC) in the multiple kV-range, but to meet the needs of a high-current demand at low output voltage levels, the modular converter concept requires adaptations. In the proposed concept, the MMC is used to step-down the three-phase medium-voltage of 10 kV. Therefore, each module is extended by an LLC resonant converter to adapt to the specific electrolyzers DC-voltage range of 142-220V and to provide galvanic isolation. The proposed MMC converter with full-bridge modules uses half the number of modules compared to a half-bridge-based MMC while reducing the voltage ripple by 78% and capacitor losses by 64% by rearranging the same components to ensure identical costs and volume. For additional reliability, a new robust algorithm for balancing conduction losses during the bypass phase is presented. author: - first_name: Roland full_name: Unruh, Roland id: '34289' last_name: Unruh - first_name: Frank full_name: Schafmeister, Frank id: '71291' last_name: Schafmeister - first_name: Norbert full_name: Fröhleke, Norbert last_name: Fröhleke - first_name: Joachim full_name: Böcker, Joachim id: '66' last_name: Böcker orcid: 0000-0002-8480-7295 citation: ama: 'Unruh R, Schafmeister F, Fröhleke N, Böcker J. 1-MW Full-Bridge MMC for High-Current Low-Voltage (100V-400V) DC-Applications. In: PCIM Europe Digital Days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management. VDE; 2020.' apa: Unruh, R., Schafmeister, F., Fröhleke, N., & Böcker, J. (2020). 1-MW Full-Bridge MMC for High-Current Low-Voltage (100V-400V) DC-Applications. PCIM Europe Digital Days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management. PCIM Europe digital days 2020, Germany. bibtex: '@inproceedings{Unruh_Schafmeister_Fröhleke_Böcker_2020, title={1-MW Full-Bridge MMC for High-Current Low-Voltage (100V-400V) DC-Applications}, booktitle={PCIM Europe digital days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management}, publisher={VDE}, author={Unruh, Roland and Schafmeister, Frank and Fröhleke, Norbert and Böcker, Joachim}, year={2020} }' chicago: Unruh, Roland, Frank Schafmeister, Norbert Fröhleke, and Joachim Böcker. “1-MW Full-Bridge MMC for High-Current Low-Voltage (100V-400V) DC-Applications.” In PCIM Europe Digital Days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management. VDE, 2020. ieee: R. Unruh, F. Schafmeister, N. Fröhleke, and J. Böcker, “1-MW Full-Bridge MMC for High-Current Low-Voltage (100V-400V) DC-Applications,” presented at the PCIM Europe digital days 2020, Germany, 2020. mla: Unruh, Roland, et al. “1-MW Full-Bridge MMC for High-Current Low-Voltage (100V-400V) DC-Applications.” PCIM Europe Digital Days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management, VDE, 2020. short: 'R. Unruh, F. Schafmeister, N. Fröhleke, J. Böcker, in: PCIM Europe Digital Days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management, VDE, 2020.' conference: end_date: 2020-07-08 location: Germany name: PCIM Europe digital days 2020 start_date: 2020-07-07 date_created: 2022-02-21T16:42:30Z date_updated: 2023-10-20T11:52:39Z department: - _id: '52' keyword: - Cascaded H-Bridge - Solid-State Transformer - Capacitor voltage ripple - Zero sequence voltage - Full-Bridge language: - iso: eng main_file_link: - url: https://ieeexplore.ieee.org/abstract/document/9178138 publication: PCIM Europe digital days 2020; International Exhibition and Conference for Power Electronics, Intelligent Motion, Renewable Energy and Energy Management publication_identifier: isbn: - 978-3-8007-5245-4 publication_status: published publisher: VDE status: public title: 1-MW Full-Bridge MMC for High-Current Low-Voltage (100V-400V) DC-Applications type: conference user_id: '34289' year: '2020' ... --- _id: '35398' abstract: - lang: eng text: The Haller relationship was applied to estimate the nematic order parameter S from 1H NMR spectra of fully protonated liquid crystals aligned in the magnetic field. The NMR line shapes were approximated as doublets of very broad peaks. Both the temperature-dependent doublet Splitting and the full width at half maximum of the whole spectra were used for Haller extrapolation. The order parameters obtained with the proposed approach for 4-cyano-4'-pentylbiphenyl (5CB) and the nematic mixture E7 were found to be in good agreement with previously reports. article_type: original author: - first_name: Ming-xue full_name: Tang, Ming-xue last_name: Tang - first_name: Claudia full_name: Schmidt, Claudia id: '466' last_name: Schmidt orcid: 0000-0003-3179-9997 citation: ama: Tang M, Schmidt C. Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals . Chinese Journal of Magnetic Resonance. 2019;36:138-147. doi:10.11938/cjmr20182685 apa: Tang, M., & Schmidt, C. (2019). Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals . Chinese Journal of Magnetic Resonance, 36, 138–147. https://doi.org/10.11938/cjmr20182685 bibtex: '@article{Tang_Schmidt_2019, title={Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals }, volume={36}, DOI={10.11938/cjmr20182685 }, journal={Chinese Journal of Magnetic Resonance}, author={Tang, Ming-xue and Schmidt, Claudia}, year={2019}, pages={138–147} }' chicago: 'Tang, Ming-xue, and Claudia Schmidt. “Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals .” Chinese Journal of Magnetic Resonance 36 (2019): 138–47. https://doi.org/10.11938/cjmr20182685 .' ieee: 'M. Tang and C. Schmidt, “Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals ,” Chinese Journal of Magnetic Resonance, vol. 36, pp. 138–147, 2019, doi: 10.11938/cjmr20182685 .' mla: Tang, Ming-xue, and Claudia Schmidt. “Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals .” Chinese Journal of Magnetic Resonance, vol. 36, 2019, pp. 138–47, doi:10.11938/cjmr20182685 . short: M. Tang, C. Schmidt, Chinese Journal of Magnetic Resonance 36 (2019) 138–147. date_created: 2023-01-06T17:29:26Z date_updated: 2023-01-07T10:31:24Z department: - _id: '2' - _id: '315' doi: '10.11938/cjmr20182685 ' intvolume: ' 36' keyword: - nematic liquid crystal - order parameter - Haller analysis - 1H NMR language: - iso: eng page: 138-147 publication: Chinese Journal of Magnetic Resonance quality_controlled: '1' related_material: link: - relation: research_paper url: http://121.43.60.238/bpxzz/EN/10.11938/cjmr20182685 status: public title: 'Estimation of Nematic Order Parameters via Haller Analysis of 1H NMR Spectra of Liquid Crystals ' type: journal_article user_id: '466' volume: 36 year: '2019' ... --- _id: '64018' abstract: - lang: eng text: CO oxidation is an extensively studied reaction in heterogeneous catalysis due to its seeming simplicity and its great importance for emission control. However, the role of particle size and more specifically structure sensitivity in this reaction is still controversial. In the present study, colloidal “surfactant-free” Pt nanoparticles (NPs) in a size regime of 1–4 nm with narrow size distribution and control over particle size were synthesized and subsequently supported on Al2O3 to prepare model catalysts. CO oxidation was performed using Pt NPs catalysts with particles sizes of 1, 2, 3, and 4 nm at different reaction temperatures. It is shown that the reaction exhibits a particle size effect that depends strongly on the reaction conditions. At 170 °C, the reaction seems to proceed within the same kinetic regime for all particle sizes, but the surface normalized activity depends strongly on the particle size, with maximum activity for nanoparticles 2 nm in diameter. A temperature increase to 200 °C leads to a change of the kinetic regime that depends on the particle size. For Pt NPs 1 nm in diameter a reaction order of 1 for O2 was observed, indicating that O2 adsorbs molecularly and dissociates in a following step, which represents the generally accepted mechanism on Pt surfaces. The reaction order of −1 for CO demonstrates that the surface is saturated with CO under reaction conditions. With increasing particle size, the reaction orders of O2 and CO change. For particles 2 nm in size, an increase in temperature also results in reaction orders of 1 for O2 and −1 for CO; NPs of 3 and 4 nm, even at higher temperatures, show no clear kinetic behavior that can be explained by a single reaction mechanism. Instead, the Boudouard reaction between two adjacent adsorbed CO molecules was identified as an important additional reaction pathway that occurs preferentially on large particles and causes more complex kinetics. author: - first_name: Sarah full_name: Neumann, Sarah last_name: Neumann - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky - first_name: Stephen full_name: Paul, Stephen last_name: Paul - first_name: Greg full_name: Thiele, Greg last_name: Thiele - first_name: Heiko full_name: Sievers, Heiko last_name: Sievers - first_name: Marcus full_name: Bäumer, Marcus last_name: Bäumer - first_name: Sebastian full_name: Kunz, Sebastian last_name: Kunz citation: ama: Neumann S, Gutmann T, Buntkowsky G, et al. Insights into the reaction mechanism and particle size effects of CO oxidation over supported Pt nanoparticle catalysts. Journal of Catalysis. 2019;377:662–672. doi:10.1016/j.jcat.2019.07.049 apa: Neumann, S., Gutmann, T., Buntkowsky, G., Paul, S., Thiele, G., Sievers, H., Bäumer, M., & Kunz, S. (2019). Insights into the reaction mechanism and particle size effects of CO oxidation over supported Pt nanoparticle catalysts. Journal of Catalysis, 377, 662–672. https://doi.org/10.1016/j.jcat.2019.07.049 bibtex: '@article{Neumann_Gutmann_Buntkowsky_Paul_Thiele_Sievers_Bäumer_Kunz_2019, title={Insights into the reaction mechanism and particle size effects of CO oxidation over supported Pt nanoparticle catalysts}, volume={377}, DOI={10.1016/j.jcat.2019.07.049}, journal={Journal of Catalysis}, author={Neumann, Sarah and Gutmann, Torsten and Buntkowsky, Gerd and Paul, Stephen and Thiele, Greg and Sievers, Heiko and Bäumer, Marcus and Kunz, Sebastian}, year={2019}, pages={662–672} }' chicago: 'Neumann, Sarah, Torsten Gutmann, Gerd Buntkowsky, Stephen Paul, Greg Thiele, Heiko Sievers, Marcus Bäumer, and Sebastian Kunz. “Insights into the Reaction Mechanism and Particle Size Effects of CO Oxidation over Supported Pt Nanoparticle Catalysts.” Journal of Catalysis 377 (2019): 662–672. https://doi.org/10.1016/j.jcat.2019.07.049.' ieee: 'S. Neumann et al., “Insights into the reaction mechanism and particle size effects of CO oxidation over supported Pt nanoparticle catalysts,” Journal of Catalysis, vol. 377, pp. 662–672, 2019, doi: 10.1016/j.jcat.2019.07.049.' mla: Neumann, Sarah, et al. “Insights into the Reaction Mechanism and Particle Size Effects of CO Oxidation over Supported Pt Nanoparticle Catalysts.” Journal of Catalysis, vol. 377, 2019, pp. 662–672, doi:10.1016/j.jcat.2019.07.049. short: S. Neumann, T. Gutmann, G. Buntkowsky, S. Paul, G. Thiele, H. Sievers, M. Bäumer, S. Kunz, Journal of Catalysis 377 (2019) 662–672. date_created: 2026-02-07T16:02:06Z date_updated: 2026-02-17T16:14:45Z doi: 10.1016/j.jcat.2019.07.049 extern: '1' intvolume: ' 377' keyword: - Solid state NMR - “Surfactant-free” platinum nanoparticles - CO oxidation - Particle size effect - Structure sensitivity language: - iso: eng page: 662–672 publication: Journal of Catalysis status: public title: Insights into the reaction mechanism and particle size effects of CO oxidation over supported Pt nanoparticle catalysts type: journal_article user_id: '100715' volume: 377 year: '2019' ... --- _id: '63960' abstract: - lang: eng text: Recent advances in solid-state nuclear magnetic resonance (NMR) spectroscopy and dynamic nuclear polarization (DNP) of nanostructured materials are reviewed. A first group of materials is based on crystalline nanocellulose (CNC) or microcrystalline cellulose (MCC), which are used as carrier materials for dye molecules, catalysts or in combination with heterocyclic molecules as ion conducting membranes. These materials have widespread applications in sensorics, optics, catalysis or fuel cell research. A second group are metal oxides such as V-Mo-W oxides, which are of enormous importance in the manufacturing process of basic chemicals. The third group are catalytically active nanocrystalline metal nanoparticles, coated with protectants or embedded in polymers. The last group includes of lead-free perovskite materials, which are employed as environmentally benign substitution materials for conventional lead-based electronics materials. These materials are discussed in terms of their application and physico-chemical characterization by solid-state NMR techniques, combined with gas-phase NMR and quantum-chemical modelling on the density functional theory (DFT) level. The application of multinuclear 1H, 2H, 13C, 15N and 23Na solid state NMR techniques under static or MAS conditions for the characterization of these materials, their surfaces and processes on their surfaces is discussed. Moreover, the analytic power of the combination of these techniques with DNP for the identification of low-concentrated carbon and nitrogen containing surface species in natural abundance is reviewed. Finally, approaches for sensitivity enhancement by DNP of quadrupolar nuclei such as 17O and 51V are presented that enable the identification of catalytic sites in metal oxide catalysts. author: - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Pedro B. full_name: Groszewicz, Pedro B. last_name: Groszewicz - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: Gutmann T, Groszewicz PB, Buntkowsky G. Solid-state NMR of nanocrystals. Annual Reports on NMR Spectroscopy. 2019;97:1–82. doi:10.1016/bs.arnmr.2018.12.001 apa: Gutmann, T., Groszewicz, P. B., & Buntkowsky, G. (2019). Solid-state NMR of nanocrystals. Annual Reports on NMR Spectroscopy, 97, 1–82. https://doi.org/10.1016/bs.arnmr.2018.12.001 bibtex: '@article{Gutmann_Groszewicz_Buntkowsky_2019, title={Solid-state NMR of nanocrystals}, volume={97}, DOI={10.1016/bs.arnmr.2018.12.001}, journal={Annual Reports on NMR Spectroscopy}, author={Gutmann, Torsten and Groszewicz, Pedro B. and Buntkowsky, Gerd}, year={2019}, pages={1–82} }' chicago: 'Gutmann, Torsten, Pedro B. Groszewicz, and Gerd Buntkowsky. “Solid-State NMR of Nanocrystals.” Annual Reports on NMR Spectroscopy 97 (2019): 1–82. https://doi.org/10.1016/bs.arnmr.2018.12.001.' ieee: 'T. Gutmann, P. B. Groszewicz, and G. Buntkowsky, “Solid-state NMR of nanocrystals,” Annual Reports on NMR Spectroscopy, vol. 97, pp. 1–82, 2019, doi: 10.1016/bs.arnmr.2018.12.001.' mla: Gutmann, Torsten, et al. “Solid-State NMR of Nanocrystals.” Annual Reports on NMR Spectroscopy, vol. 97, 2019, pp. 1–82, doi:10.1016/bs.arnmr.2018.12.001. short: T. Gutmann, P.B. Groszewicz, G. Buntkowsky, Annual Reports on NMR Spectroscopy 97 (2019) 1–82. date_created: 2026-02-07T15:37:03Z date_updated: 2026-02-17T16:17:56Z doi: 10.1016/bs.arnmr.2018.12.001 extern: '1' intvolume: ' 97' keyword: - solid-state nmr - heterogeneous catalysis - dynamic nuclear polarization - Ferroelectrics - Nanocatalysis - Surface reactions language: - iso: eng page: 1–82 publication: Annual Reports on NMR Spectroscopy status: public title: Solid-state NMR of nanocrystals type: journal_article user_id: '100715' volume: 97 year: '2019' ... --- _id: '8167' author: - first_name: Sevag full_name: Gharibian, Sevag id: '71541' last_name: Gharibian orcid: 0000-0002-9992-3379 - first_name: Jamie full_name: Sikora, Jamie last_name: Sikora citation: ama: Gharibian S, Sikora J. Ground State Connectivity of Local Hamiltonians. ACM Transactions on Computation Theory (TOCT). 2018;10(2):8:1-8:28. doi:10.1145/3186587 apa: Gharibian, S., & Sikora, J. (2018). Ground State Connectivity of Local Hamiltonians. ACM Transactions on Computation Theory (TOCT), 10(2), 8:1-8:28. https://doi.org/10.1145/3186587 bibtex: '@article{Gharibian_Sikora_2018, title={Ground State Connectivity of Local Hamiltonians}, volume={10}, DOI={10.1145/3186587}, number={2}, journal={ACM Transactions on Computation Theory (TOCT)}, publisher={ACM}, author={Gharibian, Sevag and Sikora, Jamie}, year={2018}, pages={8:1-8:28} }' chicago: 'Gharibian, Sevag, and Jamie Sikora. “Ground State Connectivity of Local Hamiltonians.” ACM Transactions on Computation Theory (TOCT) 10, no. 2 (2018): 8:1-8:28. https://doi.org/10.1145/3186587.' ieee: 'S. Gharibian and J. Sikora, “Ground State Connectivity of Local Hamiltonians,” ACM Transactions on Computation Theory (TOCT), vol. 10, no. 2, p. 8:1-8:28, 2018, doi: 10.1145/3186587.' mla: Gharibian, Sevag, and Jamie Sikora. “Ground State Connectivity of Local Hamiltonians.” ACM Transactions on Computation Theory (TOCT), vol. 10, no. 2, ACM, 2018, p. 8:1-8:28, doi:10.1145/3186587. short: S. Gharibian, J. Sikora, ACM Transactions on Computation Theory (TOCT) 10 (2018) 8:1-8:28. date_created: 2019-03-01T11:49:31Z date_updated: 2023-02-28T11:01:36Z department: - _id: '623' - _id: '7' doi: 10.1145/3186587 external_id: arxiv: - '1409.3182' intvolume: ' 10' issue: '2' keyword: - Local Hamiltonian - ground state connectivity - quantum Hamiltonian complexity - reconfiguration problem language: - iso: eng main_file_link: - open_access: '1' url: https://arxiv.org/abs/1409.3182 oa: '1' page: 8:1-8:28 publication: ACM Transactions on Computation Theory (TOCT) publication_identifier: issn: - 1942-3454 publication_status: published publisher: ACM status: public title: Ground State Connectivity of Local Hamiltonians type: journal_article user_id: '71541' volume: 10 year: '2018' ... --- _id: '64010' abstract: - lang: eng text: Seven novel dirhodium coordination polymers (Rh-2-Ln) (n = 1-7) are prepared by employing bitopic ligands to connect dirhodium nodes. The formation of the framework is confirmed by attenuated total reflectance Fourier transform infrared (ATR-FTIR) and H-1 C-13 cross polarization magic angle spinning nuclear magnetic resonance (CP MAS NMR) spectroscopy. Defect sites resulting from incomplete ligand substitution are revealed by F-19 MAS NMR. The random stacking behavior of the frameworks in the obtained solid is analyzed by scanning electron microscopy (SEM) and X-ray diffraction (XRD). The Rh-2/O interaction in neighboring layers is investigated by diffuse reflectance ultra-violet visible light (DR-UV-vis) spectroscopy and X-ray photoelectron spectroscopy (XPS). This interaction is relevant to understand the catalytic behavior of various Rh-2-Ln catalysts in the cyclopropanation of styrene with ethyl diazoacetate (EDA). In this context, the structure-reactivity relationship is discussed by taking into consideration both interlayer Rh-2/O interactions and steric effects of side chains. author: - first_name: J. Q. full_name: Liu, J. Q. last_name: Liu - first_name: Y. P. full_name: Xu, Y. P. last_name: Xu - first_name: P. B. full_name: Groszewicz, P. B. last_name: Groszewicz - first_name: M. full_name: Brodrecht, M. last_name: Brodrecht - first_name: C. full_name: Fasel, C. last_name: Fasel - first_name: K. full_name: Hofmann, K. last_name: Hofmann - first_name: X. J. full_name: Tan, X. J. last_name: Tan - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: G. full_name: Buntkowsky, G. last_name: Buntkowsky citation: ama: 'Liu JQ, Xu YP, Groszewicz PB, et al. Novel dirhodium coordination polymers: the impact of side chains on cyclopropanation. Catalysis Science & Technology. 2018;8(20):5190–5200. doi:10.1039/c8cy01493k' apa: 'Liu, J. Q., Xu, Y. P., Groszewicz, P. B., Brodrecht, M., Fasel, C., Hofmann, K., Tan, X. J., Gutmann, T., & Buntkowsky, G. (2018). Novel dirhodium coordination polymers: the impact of side chains on cyclopropanation. Catalysis Science & Technology, 8(20), 5190–5200. https://doi.org/10.1039/c8cy01493k' bibtex: '@article{Liu_Xu_Groszewicz_Brodrecht_Fasel_Hofmann_Tan_Gutmann_Buntkowsky_2018, title={Novel dirhodium coordination polymers: the impact of side chains on cyclopropanation}, volume={8}, DOI={10.1039/c8cy01493k}, number={20}, journal={Catalysis Science & Technology}, author={Liu, J. Q. and Xu, Y. P. and Groszewicz, P. B. and Brodrecht, M. and Fasel, C. and Hofmann, K. and Tan, X. J. and Gutmann, Torsten and Buntkowsky, G.}, year={2018}, pages={5190–5200} }' chicago: 'Liu, J. Q., Y. P. Xu, P. B. Groszewicz, M. Brodrecht, C. Fasel, K. Hofmann, X. J. Tan, Torsten Gutmann, and G. Buntkowsky. “Novel Dirhodium Coordination Polymers: The Impact of Side Chains on Cyclopropanation.” Catalysis Science & Technology 8, no. 20 (2018): 5190–5200. https://doi.org/10.1039/c8cy01493k.' ieee: 'J. Q. Liu et al., “Novel dirhodium coordination polymers: the impact of side chains on cyclopropanation,” Catalysis Science & Technology, vol. 8, no. 20, pp. 5190–5200, 2018, doi: 10.1039/c8cy01493k.' mla: 'Liu, J. Q., et al. “Novel Dirhodium Coordination Polymers: The Impact of Side Chains on Cyclopropanation.” Catalysis Science & Technology, vol. 8, no. 20, 2018, pp. 5190–5200, doi:10.1039/c8cy01493k.' short: J.Q. Liu, Y.P. Xu, P.B. Groszewicz, M. Brodrecht, C. Fasel, K. Hofmann, X.J. Tan, T. Gutmann, G. Buntkowsky, Catalysis Science & Technology 8 (2018) 5190–5200. date_created: 2026-02-07T15:57:34Z date_updated: 2026-02-17T16:15:22Z doi: 10.1039/c8cy01493k extern: '1' intvolume: ' 8' issue: '20' keyword: - Chemistry - asymmetric cyclopropanation - c-h insertion - carbene transformations - carboxylates - catalysts - functionalization - immobilization - metal-organic frameworks - nmr - solid support language: - iso: eng page: 5190–5200 publication: Catalysis Science & Technology publication_identifier: issn: - 2044-4753 status: public title: 'Novel dirhodium coordination polymers: the impact of side chains on cyclopropanation' type: journal_article user_id: '100715' volume: 8 year: '2018' ... --- _id: '64053' abstract: - lang: eng text: The utilization and preparation of functional hybrid films for optical sensing applications and membranes is of utmost importance. In this work, we report the convenient and scalable preparation of self-crosslinking particle-based films derived by directed self-assembly of alkoxysilane-based cross-linkers as part of a core-shell particle architecture. The synthesis of well-designed monodisperse core-shell particles by emulsion polymerization is the basic prerequisite for subsequent particle processing via the melt-shear organization technique. In more detail, the core particles consist of polystyrene (PS) or poly(methyl methacrylate) (PMMA), while the comparably soft particle shell consists of poly(ethyl acrylate) (PEA) and different alkoxysilane-based poly(methacrylate)s. For hybrid film formation and convenient self-cross-linking, different alkyl groups at the siloxane moieties were investigated in detail by solid-state Magic-Angle Spinning Nuclear Magnetic Resonance (MAS, NMR) spectroscopy revealing different crosslinking capabilities, which strongly influence the properties of the core or shell particle films with respect to transparency and iridescent reflection colors. Furthermore, solid-state NMR spectroscopy and investigation of the thermal properties by differential scanning calorimetry (DSC) measurements allow for insights into the cross-linking capabilities prior to and after synthesis, as well as after the thermally and pressure-induced processing steps. Subsequently, free-standing and self-crosslinked particle-based films featuring excellent particle order are obtained by application of the melt-shear organization technique, as shown by microscopy (TEM, SEM). author: - first_name: S. full_name: Vowinkel, S. last_name: Vowinkel - first_name: S. full_name: Paul, S. last_name: Paul - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: M. full_name: Gallei, M. last_name: Gallei citation: ama: Vowinkel S, Paul S, Gutmann T, Gallei M. Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing. Nanomaterials. 2017;7(11):390. doi:10.3390/nano7110390 apa: Vowinkel, S., Paul, S., Gutmann, T., & Gallei, M. (2017). Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing. Nanomaterials, 7(11), 390. https://doi.org/10.3390/nano7110390 bibtex: '@article{Vowinkel_Paul_Gutmann_Gallei_2017, title={Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing}, volume={7}, DOI={10.3390/nano7110390}, number={11}, journal={Nanomaterials}, author={Vowinkel, S. and Paul, S. and Gutmann, Torsten and Gallei, M.}, year={2017}, pages={390} }' chicago: 'Vowinkel, S., S. Paul, Torsten Gutmann, and M. Gallei. “Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing.” Nanomaterials 7, no. 11 (2017): 390. https://doi.org/10.3390/nano7110390.' ieee: 'S. Vowinkel, S. Paul, T. Gutmann, and M. Gallei, “Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing,” Nanomaterials, vol. 7, no. 11, p. 390, 2017, doi: 10.3390/nano7110390.' mla: Vowinkel, S., et al. “Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing.” Nanomaterials, vol. 7, no. 11, 2017, p. 390, doi:10.3390/nano7110390. short: S. Vowinkel, S. Paul, T. Gutmann, M. Gallei, Nanomaterials 7 (2017) 390. date_created: 2026-02-07T16:15:23Z date_updated: 2026-02-17T16:12:54Z doi: 10.3390/nano7110390 extern: '1' intvolume: ' 7' issue: '11' keyword: - Materials Science - Science & Technology - Other Topics - solid-state nmr - spectroscopy - catalysts - colloidal crystals - colloids - cross-linking - elastomeric opal films - emulsion polymerization - gamma-methacryloxypropyltrimethoxysilane - hybrid films - melt-shear organization - nanoparticles - particle - photons - polymers - processing - self-assembly - transition language: - iso: eng page: '390' publication: Nanomaterials publication_identifier: issn: - 2079-4991 status: public title: Free-Standing and Self-Crosslinkable Hybrid Films by Core-Shell Particle Design and Processing type: journal_article user_id: '100715' volume: 7 year: '2017' ... --- _id: '63956' abstract: - lang: eng text: The synthesis of novel robust and stable iridium-based immobilized catalysts on silica-polymer hybrid materials (Si-PB-Ir) is described. These catalysts are characterized by a combination of 1D P-31 CP-MAS and 2D P-31-H-1 HETCOR and J-resolved multinuclear solid state NMR experiments. Different binding situations such as singly and multiply coordinated phosphines are identified. Density functional theory (DFT) calculations are performed to corroborate the interpretation of the experimental NMR data, in order to propose a structural model of the heterogenized catalysts. Finally, the catalytic activity of the Si-PB-Ir catalysts is investigated for the hydrogenation of styrene employing para-enriched hydrogen gas. author: - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: S. full_name: Alkhagani, S. last_name: Alkhagani - first_name: N. full_name: Rothermel, N. last_name: Rothermel - first_name: H. H. full_name: Limbach, H. H. last_name: Limbach - first_name: H. full_name: Breitzke, H. last_name: Breitzke - first_name: G. full_name: Buntkowsky, G. last_name: Buntkowsky citation: ama: Gutmann T, Alkhagani S, Rothermel N, Limbach HH, Breitzke H, Buntkowsky G. P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts. Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics. 2017;231(3):653–669. doi:10.1515/zpch-2016-0837 apa: Gutmann, T., Alkhagani, S., Rothermel, N., Limbach, H. H., Breitzke, H., & Buntkowsky, G. (2017). P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts. Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics, 231(3), 653–669. https://doi.org/10.1515/zpch-2016-0837 bibtex: '@article{Gutmann_Alkhagani_Rothermel_Limbach_Breitzke_Buntkowsky_2017, title={P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts}, volume={231}, DOI={10.1515/zpch-2016-0837}, number={3}, journal={Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics}, author={Gutmann, Torsten and Alkhagani, S. and Rothermel, N. and Limbach, H. H. and Breitzke, H. and Buntkowsky, G.}, year={2017}, pages={653–669} }' chicago: 'Gutmann, Torsten, S. Alkhagani, N. Rothermel, H. H. Limbach, H. Breitzke, and G. Buntkowsky. “P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel Heterogenized Iridium-Catalysts.” Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics 231, no. 3 (2017): 653–669. https://doi.org/10.1515/zpch-2016-0837.' ieee: 'T. Gutmann, S. Alkhagani, N. Rothermel, H. H. Limbach, H. Breitzke, and G. Buntkowsky, “P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts,” Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics, vol. 231, no. 3, pp. 653–669, 2017, doi: 10.1515/zpch-2016-0837.' mla: Gutmann, Torsten, et al. “P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel Heterogenized Iridium-Catalysts.” Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics, vol. 231, no. 3, 2017, pp. 653–669, doi:10.1515/zpch-2016-0837. short: T. Gutmann, S. Alkhagani, N. Rothermel, H.H. Limbach, H. Breitzke, G. Buntkowsky, Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics 231 (2017) 653–669. date_created: 2026-02-07T15:35:41Z date_updated: 2026-02-17T16:18:04Z doi: 10.1515/zpch-2016-0837 extern: '1' intvolume: ' 231' issue: '3' keyword: - Chemistry - dynamic nuclear-polarization - solid-state nmr - DFT - heterogeneous catalysis - hydrido complexes - hydrogenation - immobilized catalyst - inorganic hybrid - iridium - materials - mesoporous - molecular-orbital methods - PHIP - phosphine complexes - reusable catalysts - silica - solid-state-NMR - wilkinsons catalyst language: - iso: eng page: 653–669 publication: Zeitschrift Fur Physikalische Chemie-International Journal of Research in Physical Chemistry & Chemical Physics publication_identifier: issn: - 0942-9352 status: public title: P-31-Solid-State NMR Characterization and Catalytic Hydrogenation Tests of Novel heterogenized Iridium-Catalysts type: journal_article user_id: '100715' volume: 231 year: '2017' ... --- _id: '63920' abstract: - lang: eng text: Coordinatively unsaturated sites (CUS) present a key feature of alumina based catalysts as they are believed to act as Lewis-acid sites in heterogeneously catalyzed reactions. In the present study, the direct observation of active species on a fluoride-doped aluminum oxide catalyst is demonstrated. This new fluoride-doped aluminum oxide exhibits strong Lewis-acid sites and superior catalytic activity as compared to gamma-Al2O3. To emphasize the labile state of Lewis-acid sites, two distinctive states of the catalysts surface are addressed using H-1-Al-27 cross polarization (CP) MAS NMR. On the one hand, the highly dehydrated and active state after calcination at 700 degrees C and on the other hand the rehydrated and catalytically inactive surface (produced by contact to air) are probed. These experiments revealed the presence of significant amounts of coordinatively unsaturated sites in the form of 4-and 5-fold coordinated Al-sites on the highly dehydrated surface. In contrast to this, the rehydrated sample exhibited a severely restructured surface caused by the chemisorption of H2O which is ’constituted in a manner that was proposed in earlier models for gamma-Al2O3 surfaces. author: - first_name: L. full_name: Ahrem, L. last_name: Ahrem - first_name: G. full_name: Scholz, G. last_name: Scholz - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: B. full_name: Calvo, B. last_name: Calvo - first_name: G. full_name: Buntkowsky, G. last_name: Buntkowsky - first_name: E. full_name: Kemnitz, E. last_name: Kemnitz citation: ama: Ahrem L, Scholz G, Gutmann T, Calvo B, Buntkowsky G, Kemnitz E. Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst. Journal of Physical Chemistry C. 2017;121(22):12206–12213. doi:10.1021/acs.jpcc.7b02535 apa: Ahrem, L., Scholz, G., Gutmann, T., Calvo, B., Buntkowsky, G., & Kemnitz, E. (2017). Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst. Journal of Physical Chemistry C, 121(22), 12206–12213. https://doi.org/10.1021/acs.jpcc.7b02535 bibtex: '@article{Ahrem_Scholz_Gutmann_Calvo_Buntkowsky_Kemnitz_2017, title={Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst}, volume={121}, DOI={10.1021/acs.jpcc.7b02535}, number={22}, journal={Journal of Physical Chemistry C}, author={Ahrem, L. and Scholz, G. and Gutmann, Torsten and Calvo, B. and Buntkowsky, G. and Kemnitz, E.}, year={2017}, pages={12206–12213} }' chicago: 'Ahrem, L., G. Scholz, Torsten Gutmann, B. Calvo, G. Buntkowsky, and E. Kemnitz. “Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst.” Journal of Physical Chemistry C 121, no. 22 (2017): 12206–12213. https://doi.org/10.1021/acs.jpcc.7b02535.' ieee: 'L. Ahrem, G. Scholz, T. Gutmann, B. Calvo, G. Buntkowsky, and E. Kemnitz, “Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst,” Journal of Physical Chemistry C, vol. 121, no. 22, pp. 12206–12213, 2017, doi: 10.1021/acs.jpcc.7b02535.' mla: Ahrem, L., et al. “Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst.” Journal of Physical Chemistry C, vol. 121, no. 22, 2017, pp. 12206–12213, doi:10.1021/acs.jpcc.7b02535. short: L. Ahrem, G. Scholz, T. Gutmann, B. Calvo, G. Buntkowsky, E. Kemnitz, Journal of Physical Chemistry C 121 (2017) 12206–12213. date_created: 2026-02-07T08:56:18Z date_updated: 2026-02-17T16:19:24Z doi: 10.1021/acs.jpcc.7b02535 extern: '1' intvolume: ' 121' issue: '22' keyword: - al-27 nmr - characterization - Chemistry - cross-polarization - dynamic nuclear-polarization - eta-alumina - gamma-alumina - hydroxy fluorides - ions - Materials Science - pentacoordinated al3+ - Science & Technology - Other Topics - solid-state nmr - spectroscopic - structural insights language: - iso: eng page: 12206–12213 publication: Journal of Physical Chemistry C publication_identifier: issn: - 1932-7447 status: public title: Direct Observation of Coordinatively Unsaturated Sites on the Surface of a Fluoride-Doped Alumina Catalyst type: journal_article user_id: '100715' volume: 121 year: '2017' ... --- _id: '64039' abstract: - lang: eng text: The preparation of hierarchical and sophisticated particle architectures for mimicking structural colors known from nature still remains a challenge. In this study, the preparation of novel opal and double-inverse opal films based on thermally treated metallopolymer core particles with a silica shell is described. Thermal treatment leads to the formation of magnetic nanorattle-type particles. The main challenge of artificial particles is to ensure sufficient dispersibility after several synthetic steps. Especially silica particles providing surface hydroxyl groups tend to sinter at high temperatures leading to agglomeration. We present the introduction of trimethyl ethoxy silane (TMES) as an excellent functionalization reagent as the key reaction step. The necessity and success of functionalization are investigated by transmission electron microscopy (TEM) and zeta potential measurements. Importantly, solid state NMR techniques are employed to gain deeper insights into the chemical structure of the surface-attached reagent. Finally, by this convenient functionalization the preparation of elastomeric opal films and double-inverse opal films is proven successful revealing excellent optical film properties. Moreover, magnetic properties of these novel films are investigated by using magnetic force microscopy (MFM). The herein established route is expected to pave the way for the preparation of a variety of advanced and stimuli-responsive optical materials. author: - first_name: D. full_name: Scheid, D. last_name: Scheid - first_name: D. full_name: Stock, D. last_name: Stock - first_name: T. full_name: Winter, T. last_name: Winter - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: C. full_name: Dietz, C. last_name: Dietz - first_name: M. full_name: Gallei, M. last_name: Gallei citation: ama: Scheid D, Stock D, Winter T, Gutmann T, Dietz C, Gallei M. The pivotal step of nanoparticle functionalization for the preparation of functional and magnetic hybrid opal films. Journal of Materials Chemistry C. 2016;4(11):2187–2196. doi:10.1039/c5tc04388c apa: Scheid, D., Stock, D., Winter, T., Gutmann, T., Dietz, C., & Gallei, M. (2016). The pivotal step of nanoparticle functionalization for the preparation of functional and magnetic hybrid opal films. Journal of Materials Chemistry C, 4(11), 2187–2196. https://doi.org/10.1039/c5tc04388c bibtex: '@article{Scheid_Stock_Winter_Gutmann_Dietz_Gallei_2016, title={The pivotal step of nanoparticle functionalization for the preparation of functional and magnetic hybrid opal films}, volume={4}, DOI={10.1039/c5tc04388c}, number={11}, journal={Journal of Materials Chemistry C}, author={Scheid, D. and Stock, D. and Winter, T. and Gutmann, Torsten and Dietz, C. and Gallei, M.}, year={2016}, pages={2187–2196} }' chicago: 'Scheid, D., D. Stock, T. Winter, Torsten Gutmann, C. Dietz, and M. Gallei. “The Pivotal Step of Nanoparticle Functionalization for the Preparation of Functional and Magnetic Hybrid Opal Films.” Journal of Materials Chemistry C 4, no. 11 (2016): 2187–2196. https://doi.org/10.1039/c5tc04388c.' ieee: 'D. Scheid, D. Stock, T. Winter, T. Gutmann, C. Dietz, and M. Gallei, “The pivotal step of nanoparticle functionalization for the preparation of functional and magnetic hybrid opal films,” Journal of Materials Chemistry C, vol. 4, no. 11, pp. 2187–2196, 2016, doi: 10.1039/c5tc04388c.' mla: Scheid, D., et al. “The Pivotal Step of Nanoparticle Functionalization for the Preparation of Functional and Magnetic Hybrid Opal Films.” Journal of Materials Chemistry C, vol. 4, no. 11, 2016, pp. 2187–2196, doi:10.1039/c5tc04388c. short: D. Scheid, D. Stock, T. Winter, T. Gutmann, C. Dietz, M. Gallei, Journal of Materials Chemistry C 4 (2016) 2187–2196. date_created: 2026-02-07T16:09:09Z date_updated: 2026-02-17T16:13:25Z doi: 10.1039/c5tc04388c extern: '1' intvolume: ' 4' issue: '11' keyword: - Materials Science - silica - Physics - nmr - colloidal photonic crystals - light - polymerization - solids - structural color - thermo language: - iso: eng page: 2187–2196 publication: Journal of Materials Chemistry C publication_identifier: issn: - 2050-7526 status: public title: The pivotal step of nanoparticle functionalization for the preparation of functional and magnetic hybrid opal films type: journal_article user_id: '100715' volume: 4 year: '2016' ... --- _id: '63963' abstract: - lang: eng text: A novel heterogeneous dirhodium catalyst has been synthesized. This stable catalyst is constructed from dirhodium acetate dimer (Rh2(OAc)4) units, which are covalently linked to amine- and carboxyl-bifunctionalized mesoporous silica (SBA-15NH2COOH). It shows good efficiency in catalyzing the cyclopropanation reaction of styrene and ethyl diazoacetate (EDA) forming cis- and trans-1-ethoxycarbonyl-2-phenylcyclopropane. To characterize the structure of this catalyst and to confirm the successful immobilization, heteronuclear solid-state NMR experiments have been performed. The high application potential of dynamic nuclear polarization (DNP) NMR for the analysis of binding sites in this novel catalyst is demonstrated. Signal-enhanced 13C CP MAS and 15N CP MAS techniques have been employed to detect different carboxyl and amine binding sites in natural abundance on a fast time scale. The interpretation of the experimental chemical shift values for different binding sites has been corroborated by quantum chemical calculations on dirhodium model complexes. author: - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Jiquan full_name: Liu, Jiquan last_name: Liu - first_name: Niels full_name: Rothermel, Niels last_name: Rothermel - first_name: Yeping full_name: Xu, Yeping last_name: Xu - first_name: Eva full_name: Jaumann, Eva last_name: Jaumann - first_name: Mayke full_name: Werner, Mayke last_name: Werner - first_name: Hergen full_name: Breitzke, Hergen last_name: Breitzke - first_name: Snorri T. full_name: Sigurdsson, Snorri T. last_name: Sigurdsson - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: 'Gutmann T, Liu J, Rothermel N, et al. Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst. Chemistry A European Journal. 2015;21(9):3798–3805. doi:10.1002/chem.201405043' apa: 'Gutmann, T., Liu, J., Rothermel, N., Xu, Y., Jaumann, E., Werner, M., Breitzke, H., Sigurdsson, S. T., & Buntkowsky, G. (2015). Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst. Chemistry A European Journal, 21(9), 3798–3805. https://doi.org/10.1002/chem.201405043' bibtex: '@article{Gutmann_Liu_Rothermel_Xu_Jaumann_Werner_Breitzke_Sigurdsson_Buntkowsky_2015, title={Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst}, volume={21}, DOI={10.1002/chem.201405043}, number={9}, journal={Chemistry A European Journal}, publisher={WILEY-VCH Verlag}, author={Gutmann, Torsten and Liu, Jiquan and Rothermel, Niels and Xu, Yeping and Jaumann, Eva and Werner, Mayke and Breitzke, Hergen and Sigurdsson, Snorri T. and Buntkowsky, Gerd}, year={2015}, pages={3798–3805} }' chicago: 'Gutmann, Torsten, Jiquan Liu, Niels Rothermel, Yeping Xu, Eva Jaumann, Mayke Werner, Hergen Breitzke, Snorri T. Sigurdsson, and Gerd Buntkowsky. “Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst.” Chemistry A European Journal 21, no. 9 (2015): 3798–3805. https://doi.org/10.1002/chem.201405043.' ieee: 'T. Gutmann et al., “Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst,” Chemistry A European Journal, vol. 21, no. 9, pp. 3798–3805, 2015, doi: 10.1002/chem.201405043.' mla: 'Gutmann, Torsten, et al. “Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst.” Chemistry A European Journal, vol. 21, no. 9, WILEY-VCH Verlag, 2015, pp. 3798–3805, doi:10.1002/chem.201405043.' short: T. Gutmann, J. Liu, N. Rothermel, Y. Xu, E. Jaumann, M. Werner, H. Breitzke, S.T. Sigurdsson, G. Buntkowsky, Chemistry A European Journal 21 (2015) 3798–3805. date_created: 2026-02-07T15:38:07Z date_updated: 2026-02-17T16:17:50Z doi: 10.1002/chem.201405043 extern: '1' intvolume: ' 21' issue: '9' keyword: - heterogeneous catalysis - immobilized catalyst - dynamic nuclear polarization - hyperpolarization - NMR spectroscopy language: - iso: eng page: 3798–3805 publication: Chemistry A European Journal publisher: WILEY-VCH Verlag status: public title: 'Natural Abundance 15N NMR by Dynamic Nuclear Polarization: Fast Analysis of Binding Sites of a Novel Amine-Carboxyl-Linked Immobilized Dirhodium Catalyst' type: journal_article user_id: '100715' volume: 21 year: '2015' ... --- _id: '11917' abstract: - lang: eng text: In this paper we present a speech presence probability (SPP) estimation algorithmwhich exploits both temporal and spectral correlations of speech. To this end, the SPP estimation is formulated as the posterior probability estimation of the states of a two-dimensional (2D) Hidden Markov Model (HMM). We derive an iterative algorithm to decode the 2D-HMM which is based on the turbo principle. The experimental results show that indeed the SPP estimates improve from iteration to iteration, and further clearly outperform another state-of-the-art SPP estimation algorithm. author: - first_name: Dang Hai Tran full_name: Vu, Dang Hai Tran last_name: Vu - first_name: Reinhold full_name: Haeb-Umbach, Reinhold id: '242' last_name: Haeb-Umbach citation: ama: 'Vu DHT, Haeb-Umbach R. Using the turbo principle for exploiting temporal and spectral correlations in speech presence probability estimation. In: 38th International Conference on Acoustics, Speech and Signal Processing (ICASSP 2013). ; 2013:863-867. doi:10.1109/ICASSP.2013.6637771' apa: Vu, D. H. T., & Haeb-Umbach, R. (2013). Using the turbo principle for exploiting temporal and spectral correlations in speech presence probability estimation. In 38th International Conference on Acoustics, Speech and Signal Processing (ICASSP 2013) (pp. 863–867). https://doi.org/10.1109/ICASSP.2013.6637771 bibtex: '@inproceedings{Vu_Haeb-Umbach_2013, title={Using the turbo principle for exploiting temporal and spectral correlations in speech presence probability estimation}, DOI={10.1109/ICASSP.2013.6637771}, booktitle={38th International Conference on Acoustics, Speech and Signal Processing (ICASSP 2013)}, author={Vu, Dang Hai Tran and Haeb-Umbach, Reinhold}, year={2013}, pages={863–867} }' chicago: Vu, Dang Hai Tran, and Reinhold Haeb-Umbach. “Using the Turbo Principle for Exploiting Temporal and Spectral Correlations in Speech Presence Probability Estimation.” In 38th International Conference on Acoustics, Speech and Signal Processing (ICASSP 2013), 863–67, 2013. https://doi.org/10.1109/ICASSP.2013.6637771. ieee: D. H. T. Vu and R. Haeb-Umbach, “Using the turbo principle for exploiting temporal and spectral correlations in speech presence probability estimation,” in 38th International Conference on Acoustics, Speech and Signal Processing (ICASSP 2013), 2013, pp. 863–867. mla: Vu, Dang Hai Tran, and Reinhold Haeb-Umbach. “Using the Turbo Principle for Exploiting Temporal and Spectral Correlations in Speech Presence Probability Estimation.” 38th International Conference on Acoustics, Speech and Signal Processing (ICASSP 2013), 2013, pp. 863–67, doi:10.1109/ICASSP.2013.6637771. short: 'D.H.T. Vu, R. Haeb-Umbach, in: 38th International Conference on Acoustics, Speech and Signal Processing (ICASSP 2013), 2013, pp. 863–867.' date_created: 2019-07-12T05:30:45Z date_updated: 2022-01-06T06:51:12Z department: - _id: '54' doi: 10.1109/ICASSP.2013.6637771 keyword: - correlation methods - estimation theory - hidden Markov models - iterative methods - probability - spectral analysis - speech processing - 2D HMM - SPP estimates - iterative algorithm - posterior probability estimation - spectral correlation - speech presence probability estimation - state-of-the-art SPP estimation algorithm - temporal correlation - turbo principle - two-dimensional hidden Markov model - Correlation - Decoding - Estimation - Iterative decoding - Noise - Speech - Vectors language: - iso: eng page: 863-867 publication: 38th International Conference on Acoustics, Speech and Signal Processing (ICASSP 2013) publication_identifier: issn: - 1520-6149 status: public title: Using the turbo principle for exploiting temporal and spectral correlations in speech presence probability estimation type: conference user_id: '44006' year: '2013' ... --- _id: '9784' abstract: - lang: eng text: Piezoelectric inertia motors use the inertia of a body to drive it by means of a friction contact in a series of small steps. These motors can operate in ``stick-slip'' or ``slip-slip'' mode, with the fundamental frequency of the driving signal ranging from several Hertz to more than 100 kHz. To predict the motor characteristics, a Coulomb friction model is sufficient in many cases, but numerical simulation requires microscopic time steps. This contribution proposes a much faster simulation technique using one evaluation per period of the excitation signal. The proposed technique produces results very close to those of timestep simulation for ultrasonics inertia motors and allows direct determination of the steady-state velocity of an inertia motor from the motion profile of the driving part. Thus it is a useful simulation technique which can be applied in both analysis and design of inertia motors, especially for parameter studies and optimisation. author: - first_name: Matthias full_name: Hunstig, Matthias last_name: Hunstig - first_name: Tobias full_name: Hemsel, Tobias last_name: Hemsel - first_name: Walter full_name: Sextro, Walter last_name: Sextro citation: ama: 'Hunstig M, Hemsel T, Sextro W. An efficient simulation technique for high-frequency piezoelectric inertia motors. In: Ultrasonics Symposium (IUS), 2012 IEEE International. ; 2012:277-280. doi:10.1109/ULTSYM.2012.0068' apa: Hunstig, M., Hemsel, T., & Sextro, W. (2012). An efficient simulation technique for high-frequency piezoelectric inertia motors. In Ultrasonics Symposium (IUS), 2012 IEEE International (pp. 277–280). https://doi.org/10.1109/ULTSYM.2012.0068 bibtex: '@inproceedings{Hunstig_Hemsel_Sextro_2012, title={An efficient simulation technique for high-frequency piezoelectric inertia motors}, DOI={10.1109/ULTSYM.2012.0068}, booktitle={Ultrasonics Symposium (IUS), 2012 IEEE International}, author={Hunstig, Matthias and Hemsel, Tobias and Sextro, Walter}, year={2012}, pages={277–280} }' chicago: Hunstig, Matthias, Tobias Hemsel, and Walter Sextro. “An Efficient Simulation Technique for High-Frequency Piezoelectric Inertia Motors.” In Ultrasonics Symposium (IUS), 2012 IEEE International, 277–80, 2012. https://doi.org/10.1109/ULTSYM.2012.0068. ieee: M. Hunstig, T. Hemsel, and W. Sextro, “An efficient simulation technique for high-frequency piezoelectric inertia motors,” in Ultrasonics Symposium (IUS), 2012 IEEE International, 2012, pp. 277–280. mla: Hunstig, Matthias, et al. “An Efficient Simulation Technique for High-Frequency Piezoelectric Inertia Motors.” Ultrasonics Symposium (IUS), 2012 IEEE International, 2012, pp. 277–80, doi:10.1109/ULTSYM.2012.0068. short: 'M. Hunstig, T. Hemsel, W. Sextro, in: Ultrasonics Symposium (IUS), 2012 IEEE International, 2012, pp. 277–280.' date_created: 2019-05-13T13:20:17Z date_updated: 2022-01-06T07:04:20Z department: - _id: '151' doi: 10.1109/ULTSYM.2012.0068 keyword: - friction - ultrasonic motors - Coulomb friction model - efficient simulation technique - friction contact - high-frequency piezoelectric inertia motor - motor characteristics prediction - numerical simulation - slip-slip mode - stick-slip mode - time-step simulation - ultrasonic inertia motor - Acceleration - Acoustics - Actuators - Computational modeling - Friction - Numerical models - Steady-state language: - iso: eng page: 277-280 publication: Ultrasonics Symposium (IUS), 2012 IEEE International publication_identifier: issn: - 1948-5719 quality_controlled: '1' status: public title: An efficient simulation technique for high-frequency piezoelectric inertia motors type: conference user_id: '55222' year: '2012' ... --- _id: '9759' abstract: - lang: eng text: Among various lead-free piezoelectric materials, (K,Na)NbO$_{3}$ is a very promising candidate. In this study, (K,Na)NbO$_{3}$ ceramics were sintered from mixed (K,Na)NbO$_{3}$ and NaNbO$_{3}$ powders prepared by hydrothermal reaction. These two powders were mixed with distilled water in a KNbO$_{3}$/NaNbO$_{3}$ molar ratio of 1. After sintering the mixed powder, the solid solution of (Na,K)NbO$_{3}$ ceramics was obtained. The electrical properties such as the electromechanical coupling factors k$_{p}$ and k$_{33}$, the mechanical quality factor, Q$_{m}$, and the piezoelectric constant d$_{33}$ of the sintered (K,Na)NbO$_{3}$ ceramics were 0.32, 0.48, 71 (radial mode), 118 ((33)mode), and 107 pC/N, respectively. author: - first_name: Takafumi full_name: Maeda, Takafumi last_name: Maeda - first_name: Norihito full_name: Takiguchi, Norihito last_name: Takiguchi - first_name: Takeshi full_name: Morita, Takeshi last_name: Morita - first_name: Mutsuo full_name: Ishikawa, Mutsuo last_name: Ishikawa - first_name: Tobias full_name: Hemsel, Tobias id: '210' last_name: Hemsel citation: ama: Maeda T, Takiguchi N, Morita T, Ishikawa M, Hemsel T. (K,Na)NbO3 lead-free piezoelectric ceramics synthesized from hydrothermal powders. Materials Letters. 2010;64(2):125-128. doi:10.1016/j.matlet.2009.10.012 apa: Maeda, T., Takiguchi, N., Morita, T., Ishikawa, M., & Hemsel, T. (2010). (K,Na)NbO3 lead-free piezoelectric ceramics synthesized from hydrothermal powders. Materials Letters, 64(2), 125–128. https://doi.org/10.1016/j.matlet.2009.10.012 bibtex: '@article{Maeda_Takiguchi_Morita_Ishikawa_Hemsel_2010, title={(K,Na)NbO3 lead-free piezoelectric ceramics synthesized from hydrothermal powders}, volume={64}, DOI={10.1016/j.matlet.2009.10.012}, number={2}, journal={Materials Letters}, author={Maeda, Takafumi and Takiguchi, Norihito and Morita, Takeshi and Ishikawa, Mutsuo and Hemsel, Tobias}, year={2010}, pages={125–128} }' chicago: 'Maeda, Takafumi, Norihito Takiguchi, Takeshi Morita, Mutsuo Ishikawa, and Tobias Hemsel. “(K,Na)NbO3 Lead-Free Piezoelectric Ceramics Synthesized from Hydrothermal Powders.” Materials Letters 64, no. 2 (2010): 125–28. https://doi.org/10.1016/j.matlet.2009.10.012.' ieee: T. Maeda, N. Takiguchi, T. Morita, M. Ishikawa, and T. Hemsel, “(K,Na)NbO3 lead-free piezoelectric ceramics synthesized from hydrothermal powders,” Materials Letters, vol. 64, no. 2, pp. 125–128, 2010. mla: Maeda, Takafumi, et al. “(K,Na)NbO3 Lead-Free Piezoelectric Ceramics Synthesized from Hydrothermal Powders.” Materials Letters, vol. 64, no. 2, 2010, pp. 125–28, doi:10.1016/j.matlet.2009.10.012. short: T. Maeda, N. Takiguchi, T. Morita, M. Ishikawa, T. Hemsel, Materials Letters 64 (2010) 125–128. date_created: 2019-05-13T10:21:17Z date_updated: 2022-01-06T07:04:19Z department: - _id: '151' doi: 10.1016/j.matlet.2009.10.012 intvolume: ' 64' issue: '2' keyword: - Lead-free piezoelectric material - (K - Na)NbO$_{3}$ ceramics - Sintering solid solution - Piezoelectric properties language: - iso: eng page: 125-128 publication: Materials Letters publication_identifier: issn: - 1948-5719 quality_controlled: '1' status: public title: (K,Na)NbO3 lead-free piezoelectric ceramics synthesized from hydrothermal powders type: journal_article user_id: '55222' volume: 64 year: '2010' ... --- _id: '11726' abstract: - lang: eng text: In this paper we present a robust location estimation algorithm especially focused on the accuracy in vertical position. A loosely-coupled error state space Kalman filter, which fuses sensor data of an Inertial Measurement Unit and the output of a Global Positioning System device, is augmented by height information from an altitude measurement unit. This unit consists of a barometric altimeter whose output is fused with topographic map information by a Kalman filter to provide robust information about the current vertical user position. These data replace the less reliable vertical position information provided the GPS device. It is shown that typical barometric errors like thermal divergences and fluctuations in the pressure due to changing weather conditions can be compensated by the topographic map information and the barometric error Kalman filter. The resulting height information is shown not only to be more reliable than height information provided by GPS. It also turns out that it leads to better attitude and thus better overall localization estimation accuracy due to the coupling of spatial orientations via the Direct Cosine Matrix. Results are presented both for artificially generated and field test data, where the user is moving by car. author: - first_name: Maik full_name: Bevermeier, Maik last_name: Bevermeier - first_name: Oliver full_name: Walter, Oliver last_name: Walter - first_name: Sven full_name: Peschke, Sven last_name: Peschke - first_name: Reinhold full_name: Haeb-Umbach, Reinhold id: '242' last_name: Haeb-Umbach citation: ama: 'Bevermeier M, Walter O, Peschke S, Haeb-Umbach R. Barometric height estimation combined with map-matching in a loosely-coupled Kalman-filter. In: 7th Workshop on Positioning Navigation and Communication (WPNC 2010). ; 2010:128-134. doi:10.1109/WPNC.2010.5650745' apa: Bevermeier, M., Walter, O., Peschke, S., & Haeb-Umbach, R. (2010). Barometric height estimation combined with map-matching in a loosely-coupled Kalman-filter. In 7th Workshop on Positioning Navigation and Communication (WPNC 2010) (pp. 128–134). https://doi.org/10.1109/WPNC.2010.5650745 bibtex: '@inproceedings{Bevermeier_Walter_Peschke_Haeb-Umbach_2010, title={Barometric height estimation combined with map-matching in a loosely-coupled Kalman-filter}, DOI={10.1109/WPNC.2010.5650745}, booktitle={7th Workshop on Positioning Navigation and Communication (WPNC 2010)}, author={Bevermeier, Maik and Walter, Oliver and Peschke, Sven and Haeb-Umbach, Reinhold}, year={2010}, pages={128–134} }' chicago: Bevermeier, Maik, Oliver Walter, Sven Peschke, and Reinhold Haeb-Umbach. “Barometric Height Estimation Combined with Map-Matching in a Loosely-Coupled Kalman-Filter.” In 7th Workshop on Positioning Navigation and Communication (WPNC 2010), 128–34, 2010. https://doi.org/10.1109/WPNC.2010.5650745. ieee: M. Bevermeier, O. Walter, S. Peschke, and R. Haeb-Umbach, “Barometric height estimation combined with map-matching in a loosely-coupled Kalman-filter,” in 7th Workshop on Positioning Navigation and Communication (WPNC 2010), 2010, pp. 128–134. mla: Bevermeier, Maik, et al. “Barometric Height Estimation Combined with Map-Matching in a Loosely-Coupled Kalman-Filter.” 7th Workshop on Positioning Navigation and Communication (WPNC 2010), 2010, pp. 128–34, doi:10.1109/WPNC.2010.5650745. short: 'M. Bevermeier, O. Walter, S. Peschke, R. Haeb-Umbach, in: 7th Workshop on Positioning Navigation and Communication (WPNC 2010), 2010, pp. 128–134.' date_created: 2019-07-12T05:27:04Z date_updated: 2022-01-06T06:51:07Z department: - _id: '54' doi: 10.1109/WPNC.2010.5650745 keyword: - altitude measurement unit - barometers - barometric altimeter - barometric error Kalman filter - barometric height estimation - direct cosine matrix - global positioning system - Global Positioning System - GPS device - height information - height measurement - inertial measurement unit - Kalman filters - loosely-coupled error state space Kalman filter - loosely-coupled Kalman-filter - map matching - robust information - robust location estimation - sensor fusion - topographic map information - vertical user position language: - iso: eng main_file_link: - open_access: '1' url: https://groups.uni-paderborn.de/nt/pubs/2010/BeWaPeHa10.pdf oa: '1' page: 128-134 publication: 7th Workshop on Positioning Navigation and Communication (WPNC 2010) status: public title: Barometric height estimation combined with map-matching in a loosely-coupled Kalman-filter type: conference user_id: '44006' year: '2010' ... --- _id: '11723' abstract: - lang: eng text: In this paper we present a novel vehicle tracking algorithm, which is based on multi-level sensor fusion of GPS (global positioning system) with Inertial Measurement Unit sensor data. It is shown that the robustness of the system to temporary dropouts of the GPS signal, which may occur due to limited visibility of satellites in narrow street canyons or tunnels, is greatly improved by sensor fusion. We further demonstrate how the observation and state noise covariances of the employed Kalman filters can be estimated alongside the filtering by an application of the Expectation-Maximization algorithm. The proposed time-variant multi-level Kalman filter is shown to outperform an Interacting Multiple Model approach while at the same time being computationally less demanding. author: - first_name: Maik full_name: Bevermeier, Maik last_name: Bevermeier - first_name: Sven full_name: Peschke, Sven last_name: Peschke - first_name: Reinhold full_name: Haeb-Umbach, Reinhold id: '242' last_name: Haeb-Umbach citation: ama: 'Bevermeier M, Peschke S, Haeb-Umbach R. Robust vehicle localization based on multi-level sensor fusion and online parameter estimation. In: 6th Workshop on Positioning Navigation and Communication (WPNC 2009). ; 2009:235-242. doi:10.1109/WPNC.2009.4907833' apa: Bevermeier, M., Peschke, S., & Haeb-Umbach, R. (2009). Robust vehicle localization based on multi-level sensor fusion and online parameter estimation. In 6th Workshop on Positioning Navigation and Communication (WPNC 2009) (pp. 235–242). https://doi.org/10.1109/WPNC.2009.4907833 bibtex: '@inproceedings{Bevermeier_Peschke_Haeb-Umbach_2009, title={Robust vehicle localization based on multi-level sensor fusion and online parameter estimation}, DOI={10.1109/WPNC.2009.4907833}, booktitle={6th Workshop on Positioning Navigation and Communication (WPNC 2009)}, author={Bevermeier, Maik and Peschke, Sven and Haeb-Umbach, Reinhold}, year={2009}, pages={235–242} }' chicago: Bevermeier, Maik, Sven Peschke, and Reinhold Haeb-Umbach. “Robust Vehicle Localization Based on Multi-Level Sensor Fusion and Online Parameter Estimation.” In 6th Workshop on Positioning Navigation and Communication (WPNC 2009), 235–42, 2009. https://doi.org/10.1109/WPNC.2009.4907833. ieee: M. Bevermeier, S. Peschke, and R. Haeb-Umbach, “Robust vehicle localization based on multi-level sensor fusion and online parameter estimation,” in 6th Workshop on Positioning Navigation and Communication (WPNC 2009), 2009, pp. 235–242. mla: Bevermeier, Maik, et al. “Robust Vehicle Localization Based on Multi-Level Sensor Fusion and Online Parameter Estimation.” 6th Workshop on Positioning Navigation and Communication (WPNC 2009), 2009, pp. 235–42, doi:10.1109/WPNC.2009.4907833. short: 'M. Bevermeier, S. Peschke, R. Haeb-Umbach, in: 6th Workshop on Positioning Navigation and Communication (WPNC 2009), 2009, pp. 235–242.' date_created: 2019-07-12T05:27:01Z date_updated: 2022-01-06T06:51:07Z department: - _id: '54' doi: 10.1109/WPNC.2009.4907833 keyword: - covariance matrices - expectation-maximisation algorithm - expectation-maximization algorithm - global positioning system - Global Positioning System - GPS - inertial measurement unit - interacting multiple model approach - Kalman filters - multilevel sensor fusion - narrow street canyons - narrow tunnels - online parameter estimation - parameter estimation - road vehicles - robust vehicle localization - sensor fusion - state noise covariances - time-variant multilevel Kalman filter - vehicle tracking algorithm language: - iso: eng main_file_link: - open_access: '1' url: https://groups.uni-paderborn.de/nt/pubs/2009/BePeHa09.pdf oa: '1' page: 235-242 publication: 6th Workshop on Positioning Navigation and Communication (WPNC 2009) status: public title: Robust vehicle localization based on multi-level sensor fusion and online parameter estimation type: conference user_id: '44006' year: '2009' ... --- _id: '11938' abstract: - lang: eng text: In this paper, parameter estimation of a state-space model of noise or noisy speech cepstra is investigated. A blockwise EM algorithm is derived for the estimation of the state and observation noise covariance from noise-only input data. It is supposed to be used during the offline training mode of a speech recognizer. Further a sequential online EM algorithm is developed to adapt the observation noise covariance on noisy speech cepstra at its input. The estimated parameters are then used in model-based speech feature enhancement for noise-robust automatic speech recognition. Experiments on the AURORA4 database lead to improved recognition results with a linear state model compared to the assumption of stationary noise. author: - first_name: Stefan full_name: Windmann, Stefan last_name: Windmann - first_name: Reinhold full_name: Haeb-Umbach, Reinhold id: '242' last_name: Haeb-Umbach citation: ama: Windmann S, Haeb-Umbach R. Parameter Estimation of a State-Space Model of Noise for Robust Speech Recognition. IEEE Transactions on Audio, Speech, and Language Processing. 2009;17(8):1577-1590. doi:10.1109/TASL.2009.2023172 apa: Windmann, S., & Haeb-Umbach, R. (2009). Parameter Estimation of a State-Space Model of Noise for Robust Speech Recognition. IEEE Transactions on Audio, Speech, and Language Processing, 17(8), 1577–1590. https://doi.org/10.1109/TASL.2009.2023172 bibtex: '@article{Windmann_Haeb-Umbach_2009, title={Parameter Estimation of a State-Space Model of Noise for Robust Speech Recognition}, volume={17}, DOI={10.1109/TASL.2009.2023172}, number={8}, journal={IEEE Transactions on Audio, Speech, and Language Processing}, author={Windmann, Stefan and Haeb-Umbach, Reinhold}, year={2009}, pages={1577–1590} }' chicago: 'Windmann, Stefan, and Reinhold Haeb-Umbach. “Parameter Estimation of a State-Space Model of Noise for Robust Speech Recognition.” IEEE Transactions on Audio, Speech, and Language Processing 17, no. 8 (2009): 1577–90. https://doi.org/10.1109/TASL.2009.2023172.' ieee: S. Windmann and R. Haeb-Umbach, “Parameter Estimation of a State-Space Model of Noise for Robust Speech Recognition,” IEEE Transactions on Audio, Speech, and Language Processing, vol. 17, no. 8, pp. 1577–1590, 2009. mla: Windmann, Stefan, and Reinhold Haeb-Umbach. “Parameter Estimation of a State-Space Model of Noise for Robust Speech Recognition.” IEEE Transactions on Audio, Speech, and Language Processing, vol. 17, no. 8, 2009, pp. 1577–90, doi:10.1109/TASL.2009.2023172. short: S. Windmann, R. Haeb-Umbach, IEEE Transactions on Audio, Speech, and Language Processing 17 (2009) 1577–1590. date_created: 2019-07-12T05:31:09Z date_updated: 2022-01-06T06:51:12Z department: - _id: '54' doi: 10.1109/TASL.2009.2023172 intvolume: ' 17' issue: '8' keyword: - AURORA4 database - blockwise EM algorithm - covariance analysis - linear state model - noise covariance - noise-robust automatic speech recognition - noisy speech cepstra - offline training mode - parameter estimation - speech recognition - speech recognition equipment - speech recognizer - state-space methods - state-space model language: - iso: eng main_file_link: - open_access: '1' url: https://groups.uni-paderborn.de/nt/pubs/2009/WiHa09-2.pdf oa: '1' page: 1577-1590 publication: IEEE Transactions on Audio, Speech, and Language Processing status: public title: Parameter Estimation of a State-Space Model of Noise for Robust Speech Recognition type: journal_article user_id: '44006' volume: 17 year: '2009' ... --- _id: '64055' abstract: - lang: eng text: A program for iterative fitting procedures to determine the NMR parameters from 51V solid-state MAS NMR spectra was developed. It contains options to use genetic algorithms and downhill-simplex optimizing procedures to extract the optimal parameter sets, which describe our spectra. As computational kernel the SIMPSON program is employed. Other kernels like SPINEVOLUTION are easily incorporable. The algorithms are checked for their suitability for the present optimization problem and optimal simulation conditions are determined, with the focus on minimal processing time. The procedure leads to a very good agreement between experimental and simulated spectra in a passable period of time. First results for spectra of model compounds for the active site of vanadium haloperoxidases are presented. author: - first_name: Maria full_name: Waechtler, Maria last_name: Waechtler - first_name: Annika full_name: Schweitzer, Annika last_name: Schweitzer - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Hergen full_name: Breitzke, Hergen last_name: Breitzke - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: Waechtler M, Schweitzer A, Gutmann T, Breitzke H, Buntkowsky G. Efficient analysis of 51V solid-state MAS NMR spectra using genetic algorithms. Solid State Nuclear Magnetic Resonance. 2009;35(1):37–48. doi:10.1016/j.ssnmr.2008.11.003 apa: Waechtler, M., Schweitzer, A., Gutmann, T., Breitzke, H., & Buntkowsky, G. (2009). Efficient analysis of 51V solid-state MAS NMR spectra using genetic algorithms. Solid State Nuclear Magnetic Resonance, 35(1), 37–48. https://doi.org/10.1016/j.ssnmr.2008.11.003 bibtex: '@article{Waechtler_Schweitzer_Gutmann_Breitzke_Buntkowsky_2009, title={Efficient analysis of 51V solid-state MAS NMR spectra using genetic algorithms}, volume={35}, DOI={10.1016/j.ssnmr.2008.11.003}, number={1}, journal={Solid State Nuclear Magnetic Resonance}, author={Waechtler, Maria and Schweitzer, Annika and Gutmann, Torsten and Breitzke, Hergen and Buntkowsky, Gerd}, year={2009}, pages={37–48} }' chicago: 'Waechtler, Maria, Annika Schweitzer, Torsten Gutmann, Hergen Breitzke, and Gerd Buntkowsky. “Efficient Analysis of 51V Solid-State MAS NMR Spectra Using Genetic Algorithms.” Solid State Nuclear Magnetic Resonance 35, no. 1 (2009): 37–48. https://doi.org/10.1016/j.ssnmr.2008.11.003.' ieee: 'M. Waechtler, A. Schweitzer, T. Gutmann, H. Breitzke, and G. Buntkowsky, “Efficient analysis of 51V solid-state MAS NMR spectra using genetic algorithms,” Solid State Nuclear Magnetic Resonance, vol. 35, no. 1, pp. 37–48, 2009, doi: 10.1016/j.ssnmr.2008.11.003.' mla: Waechtler, Maria, et al. “Efficient Analysis of 51V Solid-State MAS NMR Spectra Using Genetic Algorithms.” Solid State Nuclear Magnetic Resonance, vol. 35, no. 1, 2009, pp. 37–48, doi:10.1016/j.ssnmr.2008.11.003. short: M. Waechtler, A. Schweitzer, T. Gutmann, H. Breitzke, G. Buntkowsky, Solid State Nuclear Magnetic Resonance 35 (2009) 37–48. date_created: 2026-02-07T16:15:57Z date_updated: 2026-02-17T16:12:50Z doi: 10.1016/j.ssnmr.2008.11.003 extern: '1' intvolume: ' 35' issue: '1' keyword: - 51V MAS NMR spectroscopy - Genetic algorithms - Iterative fitting procedures - Model complexes for vanadium haloperoxidases language: - iso: eng page: 37–48 publication: Solid State Nuclear Magnetic Resonance status: public title: Efficient analysis of 51V solid-state MAS NMR spectra using genetic algorithms type: journal_article user_id: '100715' volume: 35 year: '2009' ... --- _id: '63951' abstract: - lang: eng text: The parameters describing the quadrupolar and CSA interactions of 51V solid-state MAS NMR investigations of model complexes mimicking vanadoenzymes as well as vanadium containing catalysts and enzyme complexes are interpreted with respect to the chemical structure. The interpretation is based on the data of 15 vanadium complexes including two new complexes with previously unpublished data and 13 complexes with data previously published by us. Correlations between the chemical structure and the 51V solid-state NMR data of this class of compounds have been established. Especially for the isotropic chemical shift δ iso and the chemical shift anisotropy δ σ , correlations with specific structural features like the coordination number of the vanadium atom, the number of coordinating nitrogens, the number of oxygen atoms and the chemical surrounding of the complex could be established for these compounds. Moreover, quantitative correlations between the solid-state NMR parameters and specific bond angles and bond lengths have been obtained. Our results can be of particular interest for future investigations concerning the structure and the mode of action of related vanadoenzymes and vanadate protein assemblies, including the use of vanadate adducts as transition state analogs for phosphate metabolizing systems. author: - first_name: Annika full_name: Fenn, Annika last_name: Fenn - first_name: Maria full_name: Wächtler, Maria last_name: Wächtler - first_name: Torsten full_name: Gutmann, Torsten id: '118165' last_name: Gutmann - first_name: Hergen full_name: Breitzke, Hergen last_name: Breitzke - first_name: Axel full_name: Buchholz, Axel last_name: Buchholz - first_name: Ines full_name: Lippold, Ines last_name: Lippold - first_name: Winfried full_name: Plass, Winfried last_name: Plass - first_name: Gerd full_name: Buntkowsky, Gerd last_name: Buntkowsky citation: ama: Fenn A, Wächtler M, Gutmann T, et al. Correlations between 51V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts. Solid State Nuclear Magnetic Resonance. 2009;36(4):192–201. doi:10.1016/j.ssnmr.2009.11.003 apa: Fenn, A., Wächtler, M., Gutmann, T., Breitzke, H., Buchholz, A., Lippold, I., Plass, W., & Buntkowsky, G. (2009). Correlations between 51V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts. Solid State Nuclear Magnetic Resonance, 36(4), 192–201. https://doi.org/10.1016/j.ssnmr.2009.11.003 bibtex: '@article{Fenn_Wächtler_Gutmann_Breitzke_Buchholz_Lippold_Plass_Buntkowsky_2009, title={Correlations between 51V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts}, volume={36}, DOI={10.1016/j.ssnmr.2009.11.003}, number={4}, journal={Solid State Nuclear Magnetic Resonance}, author={Fenn, Annika and Wächtler, Maria and Gutmann, Torsten and Breitzke, Hergen and Buchholz, Axel and Lippold, Ines and Plass, Winfried and Buntkowsky, Gerd}, year={2009}, pages={192–201} }' chicago: 'Fenn, Annika, Maria Wächtler, Torsten Gutmann, Hergen Breitzke, Axel Buchholz, Ines Lippold, Winfried Plass, and Gerd Buntkowsky. “Correlations between 51V Solid-State NMR Parameters and Chemical Structure of Vanadium (V) Complexes as Models for Related Metalloproteins and Catalysts.” Solid State Nuclear Magnetic Resonance 36, no. 4 (2009): 192–201. https://doi.org/10.1016/j.ssnmr.2009.11.003.' ieee: 'A. Fenn et al., “Correlations between 51V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts,” Solid State Nuclear Magnetic Resonance, vol. 36, no. 4, pp. 192–201, 2009, doi: 10.1016/j.ssnmr.2009.11.003.' mla: Fenn, Annika, et al. “Correlations between 51V Solid-State NMR Parameters and Chemical Structure of Vanadium (V) Complexes as Models for Related Metalloproteins and Catalysts.” Solid State Nuclear Magnetic Resonance, vol. 36, no. 4, 2009, pp. 192–201, doi:10.1016/j.ssnmr.2009.11.003. short: A. Fenn, M. Wächtler, T. Gutmann, H. Breitzke, A. Buchholz, I. Lippold, W. Plass, G. Buntkowsky, Solid State Nuclear Magnetic Resonance 36 (2009) 192–201. date_created: 2026-02-07T15:33:58Z date_updated: 2026-02-17T16:18:21Z doi: 10.1016/j.ssnmr.2009.11.003 extern: '1' intvolume: ' 36' issue: '4' keyword: - 51V NMR - Cis-dioxovanadium (v) complex - Model system - Vanadate language: - iso: eng page: 192–201 publication: Solid State Nuclear Magnetic Resonance status: public title: Correlations between 51V solid-state NMR parameters and chemical structure of vanadium (V) complexes as models for related metalloproteins and catalysts type: journal_article user_id: '100715' volume: 36 year: '2009' ...