
Assistant ProfessorDepartment of Mathematics, The University of Hong Kong Room 419, Run Run Shaw Building Pokfulam Road, Hong Kong Phone: (852) 2859 2578 Email: zhengqu[at]hku[dot]hk 






Research interests:
Papers & preprints
 Journal publications:
 O. Fercoq and Z. Qu. Restarting the accelerated coordinate descent method with a rough strong convexity estimate, Computational Optimization and Applications, 2019.
 O. Fercoq and Z. Qu. Adaptive restart of accelerated gradient methods under local quadratic growth condition, IMA Journal of Numerical Analysis, 39(4) :20692095, 2019, DOI:10.1093/imanum/drz007
 Y. Seladji and Z. Qu. Polyhedron overapproximation for complexity reduction in static analysis, International Journal of Computer Mathematics : Computer Systems Theory, 3(4):215229, 2018. DOI:10.1080/23799927.2018.1535525
 J. Konečný, Z. Qu and P. Richtárik. S2CD: semistochastic coordinate descent, Optimization Methods and Software, 32:9931005, 2017. DOI:10.1080/10556788.2017.1298596.
 S. Gaubert and Z. Qu. Checking the strict positivity of Kraus maps is NPhard, Information Processing Letters, 118:3543, 2017. DOI:10.1016/j.ipl.2016.09.008
 Z. Qu and P. Richtárik. Coordinate descent with arbitrary sampling I: algorithms and complexity, Optimization Methods and Software, 31(5):829857, 2016. DOI:10.1080/10556788.2016.1190360.
 Z. Qu and P. Richtárik. Coordinate descent with arbitrary sampling II: expected separable overapproximation, Optimization Methods and Software, 31(5):858884, 2016. DOI:10.1080/10556788.2016.1190361.
 S. Gaubert, Z. Qu and S. Sridharan. Maximizing concave piecewise affine functions on the unitary group, Optimization Letters, 10(4):655–665, 2016. DOI:10.1007/s115900150951y.
 S. Gaubert and Z. Qu. Dobrushin ergodicity coefficient for Markov operators on cones, Integral Equations and Operator Theory, 81(1):127150, 2015. DOI: 10.1007/s0002001421932.
 Z. Qu. Contraction of Riccati flows applied to the convergence analysis of a maxplus curse of dimensionality free method, SIAM Journal on Control and Optimization, 52(5):26772706, 2014. DOI: 10.1137/130906702.
 S. Gaubert and Z. Qu. The contraction rate in Thompson metric of orderpreserving flows on a cone  application to generalized Riccati equations, Journal of Differential Equations, 256(8):29022948, 2014. DOI: 10.1016/j.jde.2014.01.024.
 Preprints:
 F. Li and Z. Qu. An inexact proximal augmented Lagrangian framework with arbitrary linearly convergent inner solver for composite convex optimization, arXiv:1909.09582.
 X. Qian, Z. Qu and P. Richtárik. LSVRG and LKatyusha with arbitrary sampling, arXiv:1906.01481.
 O. Fercoq and Z. Qu. Restarting accelerated gradient methods with a rough strong convexity estimate, arXiv:1609.07358.
 Conference Proceedings (refereed):
 M. Akian, S. Gaubert, Z. Qu and O. Saadi. Solving ergodic Markov decision processes and perfect information Zerosum stochastic games by variance reduced deflated value iteration, in Proc. of the 58th Conference on Decision and Control, 2019
 X. Qian, Z. Qu and P. Richtárik. SAGA with arbitrary sampling, ICML, 2019
 Z. Qu, P. Richtárik, M. Takáč and O. Fercoq. SDNA: stochastic dual newton ascent for empirical risk minization, ICML, 2016
 D. Csiba, Z. Qu and P. Richtárik. Stochastic dual coordinate ascent with adaptive probabilities, ICML, 2015
 Z. Qu, P. Richtárik and T. Zhang. Randomized dual coordinate ascent with arbitrary Sampling, NIPS, 2015. Code
 O. Fercoq, Z. Qu, P. Richtárik and M. Takáč. Fast distributed coordinate descent for nonstrongly convex losses, in Proc. of the 24th IEEE International Workshop on Machine Learning for Signal Processing, Reims, 2014.
 Z. Qu. A maxplus based randomized algorithm for solving a class of HJB PDEs, in Proc. of the 53rd IEEE Conference on Decision and Control, pp. 1575  1580, Los Angeles, 2014. DOI:10.1109/CDC.2014.7039624
 S. Gaubert, Z. Qu and S. Sridharan. Bundlebased pruning in the maxplus curse of dimensionality free method, in Proc. of the 21st International Symposium on Mathematical Theory of Networks and Systems, Groningen, 2014.
 S. Gaubert and Z. Qu. Markov operators on cones and noncommutative consensus, in Proc. of the 12th biannual European Control Conference, pp 26932700, Zurich, 2013.
 Z. Qu. Contraction of Riccati flows applied to the convergence analysis of the maxplus curse of dimensionality free method, in Proc. of the 12th biannual European Control Conference, pp.22262231, Zurich, 2013.
 S. Gaubert, W. McEneaney and Z. Qu. Curse of dimensionality reduction in maxplus based approximation methods: theoretical estimates and improved pruning algorithms, in Proc. of the 50th IEEE Conference on Decision and Control and European Control Conference, pp.10541061, Orlando, 2014. DOI:10.1109/CDC.2011.6161386.
Teaching
 University of Hong Kong course title "MATH 2901/3901 Operation Research I", Sep. to Nov. 2018
 University of Hong Kong course title "MATH 2603/3603 Probability Theory", Sep. to Nov. 2018
 University of Hong Kong course title "MATH 2603/3603 Probability Theory", Sep. to Nov. 2017
 University of Hong Kong course title "MATH 2901/3901 Operation Research I", Jan. to Apr. 2017
 University of Hong Kong course title "MATH 2603/3603 Probability Theory", Sep. to Nov. 2016
 University of Hong Kong course title "MATH 2901/3901 Operation Research I", Jan. to Apr. 2016
 University of Hong Kong course title "MATH 2603/3603 Probability Theory", Sep. to Nov. 2015
 University of Edinburgh course CORF, course title "Computing for Operational Research and Finance", in charge of 5 lectures and 5 lab sessions for 70 postgraduate students, Sep. to Oct. 2014
 Teaching assistant: ENSTA course AO102, course title "Dynamical systems", in charge of 14h practical work sessions for 18 3rd year undergraduate students, Sep. to Nov. 2013
 Teaching assistant: ENSTA course AO102, course title "Dynamical systems", in charge of 14h practical work sessions for 18 3rd year undergraduate students, Sep. to Nov. 2012
Conference talks
 The sixth International Conference on Continuous Optimization, Berlin, Germany, Aug. 2019. slides
 SIAM Conference on Optimization, Vancouver, Canada, May. 2017. slides
 The fifth International Conference on Continuous Optimization, Tokyo, Japan, Aug. 2016. slides
 2016 Conference on Applied Mathematics , Hong Kong, Aug. 2016. slides
 The ninth ChinaR Conference, Beijing, China, May 2016. slides
 2015 International Workshops on Singal Processing, Optimization and Compressed Sensing (SPOC), Guangzhou, China, Dec. 2015.
 22nd International Symposium on Mathematical Programming, Pittsburgh, USA, July 2015. slides
 32nd International Conference on Machine Learning, Lille, France, July 2015. slides
 3rd Optimization and Big Data Workshop, Edinburgh, UK, May 2015. . slides
 53rd Conference on Decision and Control, Los Angeles, USA, December 2014. slides
 4th IMA conference on numerical algebra and optimisation, Birmingham, UK, Sep., 2014.
 12th European Control Conference, Zurich, Switzerland, July, 2013.
 SIAM annual meeting, San Diego, California, U.S.A., July, 2013.
 SMAI 2013, Seignosse, France, May, 2013.
 PGMO (Program Gaspard Monge pour l'Optimisation et la recherche opérationnelle), monthly seminar, France, Feb., 2013.
 Seminar Digiteo, Ecole Polytechnique, France, Mar., 2012.
 50th IEEE Conference on Decision and Control, Orlando, U.S.A., Dec., 2011.
 Second Monterey Workshop on Computational Issues in Nonlinear Control, Monterey, U.S.A., Nov., 2011.