Prof. Dr. sc. techn.

Wolfgang Keller

retired

Contact

+49 711 685-83285

Geschwister-Scholl-Str. 24D
70174 Stuttgart
Deutschland

  1. 2019

    1. Javaid, M., & Keller, W. (2019). Data mining of spherical harmonic (SH) coefficients using artificial neural networks (ANN). EGU, Wien, 7--12 April 2019.
  2. 2016

    1. Javaid, M. A., & Keller, W. (2016a). Comparison of two gravity recovery algorithms based on the variational equation approach. Second International Conference on Space, COMSTECH Secretariat, 33-Constitution Avenue, G-5/2, Islamabad, Pakistan.
    2. Javaid, M. A., & Keller, W. (2016b). Data mining for Monthly Spherical Harmonics (SH) Coefficients from GRACE satellite. Second International Conference on Space, COMSTECH Secretariat, 33-Constitution Avenue, G-5/2, Islamabad, Pakistan.
  3. 2015

    1. Antoni, Markus, Keller, W., Kersten, T., & Schön, S. (2015). Alternative GNSS antenna calibration in terms of Bernstein-Bezier polynomials. Retrieved from https://opencms.uni-stuttgart.de/fak6/gis/forschung/doc/ANTO_2015a.pdf
    2. Keller, Wolfgang. (2015a). Data mining in GRACE monthly solutions (solicited). European Geosciences Union General Assembly 2015, Vienna, Austria.
    3. Keller, Wolfgang. (2015b). Data mining in SST monthly solutions. 26th IUGG general Assembly 2015, Prague, Czech Republik.
    4. Keller, Wolfgang, & You, R.-J. (2015). Rosborough approach for the determination of regional time variability of the gravity field from satellite gradiometry data. 6(2), 295--318. https://doi.org/10.1007/s13137-015-0077-5
    5. Keller, Wolfgang. (2015c). Satellite-to-Satellite Tracking (Low-Low/High-Low SST). In W. Freeden, Z. Nashed, & T. Sonar (Eds.), Handbook of Geomathematics (pp. 171--210; By W. Freeden, Z. Nashed, & T. Sonar). Springer-Verlag, Berlin Heidelberg.
  4. 2014

    1. Keller, W, & You, R. J. (2014). Adaptation of the torus and Rosborough approach to radial base functions. 58(2), 249--268. https://doi.org/10.1007/s11200-013-0157-7
    2. Antoni, Markus, Roth, M., & Keller, W. (2014). Construction of directional wavelets on the sphere. Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/ANTO_2014a.pdf
  5. 2013

    1. Antoni, Markus, Weigelt, M., Keller, W., & Van Dam, T. (2013). Boundary elements for modelling gravitational signals observed by inter-satellite ranging. Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/ANTO_2013a.pdf
    2. Antoni, Markus, & Keller, W. (2013). Closed solution of the Hill differential equation for short arcs and a local mass anomaly in the central body. 115(2), 107--121. https://doi.org/10.1007/s10569-012-9454-7
    3. Roth, M, Sneeuw, N., & Keller, W. (2013). Euler Deconvolution of GOCE Gravity Gradiometry Data. In W. Nagel, D. Kröner, & M. Resch (Eds.), High Performance Computing in Science and Engineering ’12 (pp. 503--515; By W. Nagel, D. Kröner, & M. Resch). https://doi.org/10.1007/978-3-642-33374-3_36
    4. Cramer, M., Schwieger, V., Fritsch, D., Keller, W., Kleusberg, A., & Sneeuw, N. (2013). Geoengine -- The University of Stuttgart International Master Program with more than 6 years of experience. Environment for Sustainability, 19. Retrieved from http://www.fig.net/resources/proceedings/fig_proceedings/fig2013/papers/ts01e/TS01E_cramer_schwieger_et_al_6689.pdf
    5. Weigelt, M., Van Dam, T., Jäggi, A., Prange, L., Sneeuw, N., & Keller, W. (2013). Long-term mass changes over Greenland derived from high-low satellite-to-satellite tracking. Retrieved from http://www.bernese.unibe.ch/publist/2013/post/EGU2013_Weigeltetal_Greenland.pdf
    6. Weigelt, M., Van Dam, T., Jäggi, A., Prange, L., Tourian, M. J., Keller, W., & Sneeuw, N. (2013). Time-variable gravity signal in Greenland revealed by high-low satellite-to-satellite tracking. 118(7), 3848--3859. https://doi.org/10.1002/jgrb.50283
  6. 2012

    1. Roth, Matthias, Baur, O., & Keller, W. (2012). ``Brute-force’’ solution of large-scale systems of equations in a MPI-PBLAS-ScaLAPACK environment. In W. E. Nagel, D. B. Kröner, & M. M. Resch (Eds.), High Performance Computing in Science and Engineering ’11 (pp. 581--594; By W. E. Nagel, D. B. Kröner, & M. M. Resch). https://doi.org/10.1007/978-3-642-23869-7_42
    2. Roth, M, Sneeuw, N., & Keller, W. (2012). Euler deconvolution of GOCE gravity gradiometry data. The 15th Results and Review Workshop, HLRS Stuttgart, Germany.
    3. Weigelt, M., Van Dam, T., Jäggi, A., Prange, L., Sneeuw, N., & Keller, W. (2012). Large scale time variability from high-low SST -- filling the gap between GRACE and GFO. GRACE Science Team Meeting GSTM 2012, Potsdam, Germany.
    4. Antoni, Markus, & Keller, W. (2012). Local improvement of GRACE gravity field solutions using SO(3) representations. Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/ANTO_2012a.pdf
    5. Weigelt, M., Keller, W., & Antoni, M. (2012). On the comparison of radial base functions and single layer density representations in local gravity field modeling from simulated satellite observations. In N. Sneeuw, P. Novák, M. Crespi, & F. Sansò (Eds.), Proceedings VII Hotine-Marussi Symposium on Mathematical Geodesy, Rome, Italy (pp. 199--204; By N. Sneeuw, P. Novák, M. Crespi, & F. Sansò). https://doi.org/10.1007/978-3-642-22078-4_29
    6. Weigelt, M., & Keller, W. (2012). Refinement of the differential gravimetry approach for future inter-satellite observations. EGU General Assembly, Vienna, Austria.
    7. Weigelt, M., Jäggi, A., Prange, L., Chen, Q., Keller, W., & Sneeuw, N. (2012). Time variability from high-low SST -- filling the gap between GRACE and GFO. Retrieved from http://www.bernese.unibe.ch/publist/2012/pres/Pres_GGHS2012_Weigeltetal.pdf
    8. Keller, W. (2012). Wavelet compression of geodetic integral operators. EGU General Assembly, Vienna, Austria.
  7. 2011

    1. Roth, M., Baur, O., & Keller, W. (2011). ``Brute-force’’ solution of large-scale systems of equations in a MPI-PBLAS-ScaLAPACK environment. The 14th Results and Review Workshop of the HLRS, Stuttgart, Germany.
    2. Keller, W, Kuhn, M., & Featherstone, W. E. (2011). A set of analytical formulae to model deglaciation-induced polar wander. In S. Kenyon, M. C. Pacino, & U. Marti (Eds.), Geodesy for the Planet Earth (pp. 527--537; By S. Kenyon, M. C. Pacino, & U. Marti). https://doi.org/10.1007/978-3-642-20338-1_64
    3. Antoni, Markus, Keller, W., & Weigelt, M. (2011). Comparison of genetic algorithm and descend direction algorithm for SST data. Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/ANTO_2011a.pdf
    4. Weigelt, M., & Keller, W. (2011). GRACE Gravity Field Solutions Using the Differential Gravimetry Approach.- Earth on the Edge :Science for a Sustainable Planet. IUGG General Assembly , Melbourne, Australia.
    5. Keller, W, & Hajkova, J. (2011). Representation of planar integral-transformations by 4-D wavelet decomposition. 85(6), 341--356. https://doi.org/10.1007/s00190-010-0440-0
    6. Keller, W. (2011a). Representation of planar integral-transformations by 4-D wavelet decomposition. EGU General Assembly, Vienna, Austria.
    7. Roth, M, Baur, O., & Keller, W. (2011). Tailored usage of the NEC SX-8 and SX-9 systems in satellite geodesy. In W. E. Nagel, D. B. Kröner, & M. M. Resch (Eds.), High Performance Computing in Science and Engineering ’10 (pp. 561--572; By W. E. Nagel, D. B. Kröner, & M. M. Resch). https://doi.org/10.1007/978-3-642-15748-6_41
    8. Weigelt, M., Jäggi, A., Prange, L., Keller, W., & Sneeuw, N. (2011). Towards the time-variable gravity field from CHAMP. IUGG General Assembly - Earth on the Edge: Science for a Sustainable Planet, Melbourne, Australia.
    9. Keller, W. (2011b). Umordnung großer, schwach besetzter Normalgleichungsmatrizen mithilfe graphen-theoretischer und genetischer Algorithmen. Retrieved from http://www.uni-stuttgart.de/gi/research/Geodaetische_Woche/2011/Session6/S6-08-Keller.pdf
    10. Keller, W, & Borkowski, A. (2011). Wavelet based buildings segmentation in airborne laser scanning data sets. 60(2), 99--121. https://doi.org/10.2478/v10277-012-0010-0
  8. 2010

    1. Weigelt, M., Sneeuw, N., & Keller, W. (2010). Evaluation of EGM2008 by Comparison with Global and Local Gravity Solutions from CHAMP. In S. P. Mertikas (Ed.), Gravity, Geoid and Earth Observation (pp. 497--504; By S. P. Mertikas). https://doi.org/10.1007/978-3-642-10634-7
    2. Kuhn, M., Schmid, S., Rieser, D., Anjsmara, I., Baur, O., & Keller, W. (2010). Monitoring mass transport in the Murray-Darling basin, Australia, using GRACE time-variable gravity: TRMM precipitation and river level/flow observations. Second International Symposium of the International Gravity Field Service, Fairbanks, Alaska, USA.
    3. Weigelt, M., & Keller, W. (2010). Numerische Aspekte bei der Berechnung von GRACE Schwerefeldern mit Hilfe des Ansatzes der differentiellen Gravimetrie. Geodätische Woche, Köln, Germany.
    4. Roth, M, Baur, O., & Keller, W. (2010). Tailored usage of the NEC SX-8 and SX-9 systems in satellite geodesy. High Performance Computing in Science and Engineering -- the 13th Results and Review Workshop of the HLRS, Stuttgart, Germany.
  9. 2009

    1. Keller, W, Antoni, M., & Weigelt, M. (2009). A Closed Solution of the Variational Equations for Short-Arc SST. IAG General Assembly 2009, Buenos Aires, Argentina.
    2. Keller, W. (2009). A Geometric Perspective to the Boundary Value Problem of Physical Geodesy. In P. Holota (Ed.), Mission and Passion: Science. A volume dedicated to Milan Bursa on the occasion of his 80th birthday (pp. 125--135; By P. Holota). Prague, Czech Republic.
    3. Keller, W, Kuhn, M., & Featherstone, W. E. (2009). A set of analytical formulae to model deglaciation-induced polar wander. IAG General Assembly 2009, Buenos Aires, Argentina.
    4. Antoni, Markus, Keller, W., & Weigelt, M. (2009a). Analyse von GRACE-Beobachtungen durch optimierte radiale Basisfunktionen (2). Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/ANTO_2009d.pdf
    5. Weigelt, M., Keller, W., & Antoni, M. (2009a). Comparing the local gravity field recovery based on radial base functions with the boundary element method. Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/WEIG_2009a.pdf
    6. Baur, O., & Keller, W. (2009). Computational considerations for satellite-based geopotential recovery. In W. E. Nagel, D. B. Kröner, & M. M. Resch (Eds.), High Performance Computing in Science and Engineering ’09 (pp. 511--521; By W. E. Nagel, D. B. Kröner, & M. M. Resch). https://doi.org/10.1007/978-3-642-04665-0_35
    7. Kuhn, M., Featherstone, W. E., Makarynskyy, O., & Keller, W. (2009). Deglaciation-Induced Spatially Variable Sea-level Change: A Simple-Model Case Study for the Greenland and Antarctic Ice Sheets. https://doi.org/10.1260/1759-3131.1.2.67
    8. Awange, J. L., Sharifi, M. A., Baur, O., Keller, W., Featherstone, W. E., & Kuhn, M. (2009). GRACE hydrological monitoring of Australia: current limitations and future prospects. 54(1), 23--36. https://doi.org/10.1080/14498596.2009.9635164
    9. Weigelt, M., Keller, W., & Antoni, M. (2009b). Lokale Schwerefeldbestimmung mit Hilfe der Randelementemethode und radialen Basisfunktionen. Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/WEIG_2009b.pdf
    10. Antoni, Markus, Keller, W., & Weigelt, M. (2009b). Recovery of residual GRACE-observations by radial base functions. Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/ANTO_2009c.pdf
    11. Antoni, Markus, Keller, W., & Weigelt, M. (2009c). Representation of Regional Gravity Fields by Radial Base Functions. In M. G. Sideris (Ed.), Observation our Changing Earth, Proceedings of the 2007 IAG General Assembly, Perugia, Italy (pp. 293--299; By M. G. Sideris). https://doi.org/10.1007/978-3-540-85426-5_34
    12. Austen, G., & Keller, W. (2009). Singularity free formulations of the geodetic boundary value problem in gravity space. 83(7), 645--657. https://doi.org/10.1007/s00190-008-0278-x
    13. Antoni, Markus, Borkowski, A., Keller, W., & Owczarek, M. (2009). Verification of localized GRACE solutions by the Polish quasiqeoid. 58(2), 21--36.
  10. 2008

    1. Keller, W. (2008). A Localizing Basis Function Representation for Low-Low Mode SST and Gravity Gradients Observations. In P. Xu, J. Liu, & A. Dermanis (Eds.), VI Hotine-Marussi Symposium on Theoretical and Computational Geodesy, Wuhan, PR China (pp. 10--16; By P. Xu, J. Liu, & A. Dermanis). https://doi.org/10.1007/978-3-540-74584-6_2
    2. Antoni, Markus, Keller, W., & Weigelt, M. (2008). Analyse der GRACE-Beobachtungen durch optimierte radiale Basisfunktionen. Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/ANTO_2008b.pdf
    3. Weigelt, M., Sneeuw, N., & Keller, W. (2008). Evaluation of PGM2007A by comparison with globally and locally estimated gravity solutions from CHAMP. IAG International Symposium on Gravity, Geoid and Earth Observations (GGEO 2008), Chania, Crete, Greece.
    4. Awange, J. L., Sharifi, M. A., Baur, O., Keller, W., Featherstone, W. E., & Kuhn, M. (2008). GRACE hydrological monitoring of Australia: current limitations and future prospects. IAG International Symposium on Gravity, Geoid and Earth Observations (GGEO 2008), Chania, Crete, Greece.
    5. Sneeuw, N., Sharifi, M. A., & Keller, W. 29. 5.-2. 6. 2006). (2008). Gravity Recovery from Formation Flight Missions. In P. Xu, J. Liu, & A. Dermanis (Eds.), VI Hotine-Marussi Symposium on Theoretical and Computational Geodesy, Wuhan, PR China (pp. 29--34; By P. Xu, J. Liu, & A. Dermanis). https://doi.org/10.1007/978-3-540-74584-6_5
    6. Weigelt, M., & Keller, W. (2008). Line-of-sight Gradiometrie und ihre praktische Umsetzung im Falle von GRACE. Geodätische Woche, Bremen, Germany.
    7. Weigelt, M., Antoni, M., & Keller, W. (2008). Regional gravity recovery from GRACE using position optimized radial base functions. Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/WEIG_2008a.pdf
    8. Antoni, M, Keller, W., & Weigelt, M. (2008). Regionale Schwerefeldmodellierung durch Slepian- und radiale Basisfunktionen. 133(2), 120--129. Retrieved from http://geodaesie.info/zfv/heftbeitrag/597
  11. 2007

    1. Sharifi, M., Sneeuw, N., & Keller, W. (2007). Gravity recovery capability of four generic satellite formations. In A. Kiliçoglu & R. Forsberg (Eds.), Gravity field of the Earth: General Command of Mapping: Vol. 18 (special issue) (pp. 211--216; By A. Kiliçoglu & R. Forsberg). 1st Int. Symp. of the International Gravity Field Service, Istanbul, Turkey.
    2. Austen, G., & Keller, W. (2007). On an ellipsoidal approach to the singularity-free gravity space theory. In P. Xu, J. Liu, & A. Dermanis (Eds.), VI Hotine-Marussi Symposium on Theoretical and Computational Geodesy, Wuhan, China (pp. 327--332; By P. Xu, J. Liu, & A. Dermanis). https://doi.org/10.1007/978-3-540-74584-6_53
    3. Antoni, Markus, Keller, W., & Weigelt, M. (2007). Representation of Regional Gravity Fields by Radial Base Functions. Retrieved from https://www.gis.uni-stuttgart.de/forschung/doc/ANTO_2007a.pdf
    4. Keller, W. (2007). Self-adaptive choice of a system of localizing base function for regional gravity field recovery. IUGG XXIV General Assembly (IUGG 2007), Perugia, Italy.
    5. Weigelt, M., Van Der Wal, W., Sneeuw, N., Keller, W., & Baur, O. (2007). Time variable gravity field recovery in local areas by means of Slepian functions. IUGG XXIV General Assembly (IUGG 2007), Perugia, Italy.
  12. 2006

    1. Wang, J., Keller, W., & Sharifi, M. A. (2006). Comparison of Availability of GALILEO, GPS and Combined GALILEO/GPS Navigation Systems. 41, 3--15. https://doi.org/10.2478/v10018-007-0001-9
    2. Baur, O., Austen, G., & Keller, W. (2006). Efficient Satellite Based Geopotential Recovery. In W. E. Nagel, W. Jäger, & M. Resch (Eds.), High Performance Computing in Science and Engineering ’06 (pp. 499--514; By W. E. Nagel, W. Jäger, & M. Resch). https://doi.org/10.1007/978-3-540-36183-1_36
    3. Götzelmann, M., Keller, W., & Reubelt, T. (2006). Gross error compensation for gravity field analysis based on kinematic orbit data. 80(4), 184--198. https://doi.org/10.1007/s00190-006-0061-9
    4. Austen, G., & Keller, W. (2006a). LSQR Tuning to Succeed in Computing High Resolution Gravity Field Solutions. In P. Alberigo, G. Erbacci, & F. Garofalo (Eds.), Science and Supercomputing in Europe, HPC-Europa Transnational Access Report 2005 (pp. 307--311; By P. Alberigo, G. Erbacci, & F. Garofalo). Monograf s.r.l., Bologna, Italy.
    5. Austen, G., & Keller, W. (2006b). Numerical implementation of the Gravity Space approach -- proof of concept. In C. Rizos & P. Tregoning (Eds.), Dynamic Planet -- Monitoring and Understanding a Dynamic Planet with Geodetic and Oceanographic Tools (pp. 296--302; By C. Rizos & P. Tregoning). https://doi.org/10.1007/978-3-540-49350-1_44
  13. 2005

    1. Borkowski, A., & Keller, W. (2005). Global and local methods for tracking the intersection curve between two surfaces. 79(1), 1--10. https://doi.org/10.1007/s00190-005-0437-2
    2. Sharifi, M. A., & Keller, W. (2005). GRACE Gradiometer. In C. Jekeli, L. Bastos, & J. Fernandes (Eds.), Gravity, Geoid and Space Mission (pp. 42--47; By C. Jekeli, L. Bastos, & J. Fernandes). https://doi.org/10.1007/3-540-26932-0_8
    3. Keller, W, & Sharifi, M. (2005). Satellite Gradiometry Using a Satellite Pair. 78(9), 544--557. https://doi.org/10.1007/s00190-004-0426-x
    4. Austen, G., Baur, O., & Keller, W. (2005). Use of high performance computing in gravity field research. In W. Nagel, W. Resch, & W. Jäger (Eds.), High Performance Computing in Science and Engineering’ 05 (pp. 305--318; By W. Nagel, W. Resch, & W. Jäger). https://doi.org/10.1007/3-540-29064-8_24
  14. 2004

    1. Keller, W, Kubik, K., & Mojarrabi, B. (2004). Bi-static SAR using GPS Signals reflected at the Sea-surface. Proceedings EUSAR 2004, 2, 779--783. 5th European Conference on Synthetic Aperture Radar, EUSAR2004, Ulm, Germany: VDE Verlag.
    2. Keller, W. (2004a). The use of wavelets for the acceleration of iteration schemes. In F. Sansò (Ed.), V. Hotine-Marussi Symposium on Mathematical Geodesy (pp. 81--87; By F. Sansò). https://doi.org/10.1007/978-3-662-10735-5_10
    3. Keller, W. (2004b). Wavelets in Geodesy and Geodynamics (p. 279). De Gruyter.
  15. 2003

    1. Borkowski, A., & Keller, W. (2003). Modelling of Irregularly Sampled Surfaces by two-dimensional Snakes. 77(9), 543--553. https://doi.org/10.1007/s00190-003-0354-1
  16. 2001

    1. Keller, W. (2001). A wavelet solution to 1D non-stationary collocation with an extension to 2D case. In M. G. Sideris (Ed.), Gravity, Geoid and Geodynamics 2000 (pp. 79--85; By M. G. Sideris). https://doi.org/10.1007/978-3-662-04827-6_13
  17. 2000

    1. Keller, W. (2000). A wavelet approach to non-stationary collocation. In K. P. Schwarz (Ed.), Geodesy Beyond 2000 -- The Challenges of the First Decade (pp. 208--213; By K. P. Schwarz). https://doi.org/10.1007/978-3-642-59742-8_34
    2. Gilbert, A., & Keller, W. (2000). Deconvolution with wavelets and vaguelettes. 74(3--4), 306--320. https://doi.org/10.1007/s001900050288
  18. 1999

    1. Keller, W. (1999). Geodetic pseudodifferential operators and the Meissl scheme. In F. Krumm & V. S. Schwarze (Eds.), Quo vadis geodesia...? Festschrift for Erik W. Grafarend on the occasion of his 60th birthday (pp. 237--246; By F. Krumm & V. S. Schwarze). Retrieved from http://www.uni-stuttgart.de/gi/research/schriftenreihe/quo_vadis/pdf/keller.pdf
    2. Heß, D., & Keller, W. (1999a). Gradiometrie mit GRACE, Teil I. 124, 137--144.
    3. Heß, D., & Keller, W. (1999b). Gradiometrie mit GRACE, Teil II. 124, 205--211.
  19. 1997

    1. Keller, W. (1997a). A Wavelet-Vaguelette Analysis of Geodetic Integral Formulae. In J. Segawa, H. Fujimoto, & K. Okubo (Eds.), Gravity, Geoid and Marine Geodesy (pp. 557--564; By J. Segawa, H. Fujimoto, & K. Okubo). https://doi.org/10.1007/978-3-662-03482-8_74
    2. Keller, W. (1997b). Anwendung von Wavelets in der Verarbeitung geowissenschaftlicher Daten. 122, 334--339.
    3. Keller, W. (1997c). Application of Boundary Value Techniques to Satellite Gradiometry. In F. Sansó & R. Rummel (Eds.), Geodetic Boundary Value Problems in View of the One Centimeter Geoid (pp. 542--558; By F. Sansó & R. Rummel). https://doi.org/10.1007/BFb0011716
    4. Keller, W. (1997d). Schnelle Algorithmen zur diskreten Wavelet Transformation. 122, 126--135.
  20. 1996

    1. Bláha, T., Hirsch, M., Keller, W., & Scheinert, M. (1996). Application of a spherical FFT approach in airborne gravimetry. 70(11), 663--672. https://doi.org/10.1007/BF00867145
    2. Keller, W. (1996a). Inversion of STEP-observation equation using Banach’s fixed-point principle. In B. H. Jacobsen, K. Mosegaard, & P. Sibani (Eds.), Inverse Methods: Interdisciplinary Elements of Methodology, Computation, and Applications (pp. 247--253; By B. H. Jacobsen, K. Mosegaard, & P. Sibani). https://doi.org/10.1007/BFb0011783
    3. Keller, W. (1996b). Kontinuierliche Wavelet Transformation. 121, 563--572.
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