Vissarion Fisikopoulos

Computer Engineer & Research Scientist — geometric computing, optimization, computational statistics, open-source software

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Status

  • Co-founder and coordinator of the GeomScale project, conducting R&D on high-dimensional geometric computing, statistics, and optimization.

  • Researcher at the DSO lab, NTUA, working on satellite trajectories, including methods and software for precise orbit determination (POD) and positioning.

  • Software engineer in the LibreOffice project, focusing on Base development, the suite’s database front end and database management component.

  • Lecturer at the Department of Informatics and Telecommunications of NKUA, teaching MSc courses and supervising diploma theses.

  • Scientific collaborator with the OURAGAN team at INRIA.

Short Bio

Spent a decade at Oracle/MySQL, developing geometric algorithms for GIS in Boost.Geometry and MySQL.

Previously, was a postdoctoral researcher in the Algorithms Research Group at Université libre de Bruxelles (ULB), working with Prof. Samuel Fiorini on combinatorial optimization and polyhedral combinatorics [cite:17][cite:20][cite:29]. Before that, was a visiting researcher at the National Institute for Mathematical Sciences in South Korea and a researcher at the University of Athens.

Holds a PhD in Computer Science from the University of Athens, supervised by Prof. Ioannis Emiris, an MSc in Logic, Algorithms and Computation from the University of Athens, and a Diploma (5-year degree) in Computer Engineering & Computer Science from CEID, University of Patras.

Research Interests

  • Foundations of data science: sampling, integration, optimization.
  • Mathematical software, computational statistics, algorithm engineering, open-source software.
  • Linear algebra, (high-dimensional) computational geometry, robust computation.
  • GIS, spatial databases, satellite geodesy, precise orbit determination (POD), positioning.
  • Applications in computational finance and structural biology.

selected publications

  1. Dingo: a Python Package for Metabolic Flux Sampling
    Apostolos Chalkis, Vissarion Fisikopoulos, Elias Tsigaridas, and 1 more author
    Bioinformatics Advances, 2024
  2. Truncated Log-Concave Sampling for Convex Bodies with Reflective Hamiltonian Monte Carlo
    Apostolos Chalkis, Vissarion Fisikopoulos, Marios Papachristou, and 1 more author
    ACM Transactions on Mathematical Software, 2023
  3. Enumeration of 2-Level Polytopes
    Y. Faenza, S. Fiorini, V. Fisikopoulos, and 2 more authors
    Mathematical Programming Computation, 2019
  4. Practical Polytope Volume Approximation
    I.Z. Emiris and V. Fisikopoulos
    ACM Transactions on Mathematical Software, 2018