Research Activities

Invited Talks

• Ordered Banach spaces: embeddings and structure preserving operators
  University of the Witwatersrand, Johannesburg, South Africa, February 2023
• An order theoretic analysis of atomic JBW-algebras
  COSA 2023 workshop, Tozeur, Tunisia, February 2023
• Bi-Riesz homomorphisms in partially ordered vector spaces
  Online lecture, Faculte des Sciences de Tunis, Tunisia,  December 2019
• Ordered Banach spaces: embeddings and disjointness preserving operators
  Universitatea Babes-Bolyai din Cluj-Napoca, Department of Mathematics, Romania, October 2019
• Ordered Banach spaces: embeddings and disjointness preserving operators
  Workshop on Banach spaces and Banach lattices, Instituto de Ciencias Matemáticas, Madrid, Spain, September 2019
• Pre-Riesz spaces: embeddings and structure preserving operators
  Conference Positivity X, Department of Mathematics and Applied Mathematics, University of Pretoria, South Africa, July 2019
• Partially ordered vector spaces: embedding techniques and structure preserving operators
  Indian Institute of Technology Madras, Department of Mathematics, Chennai, India,
  February 2019
• Partially ordered vector spaces
  Workshop: Order structures, Jordan algebras, and geometry.
  Lorentz Center, Leiden, The Netherlands, June 2017
• Ideals and bands in pre-Riesz spaces
  South. Mathematical Institute of Vladikavkaz Scientific Centre,
  Russian Academy of Sciences, May 2015
• Positive dynamische Systeme und Strukturen in prä-Riesz-Räumen
  Universität Kassel, Fachbereich Mathematik, Juli 2012
• Substructures in partially ordered vector spaces seen in the light of functional representations
  University of Kent, Canterbury, U.K., June 2011
• Stabilitätsradien positiver Systeme - dynamische Gleichungen auf Zeitskalen Universität Tübingen, AG Funktionalanalysis, Januar 2009.
• M-operators on ordered normed spaces
  Leiden University, The Netherlands, February 2006
• Disjointness in partially ordered vector spaces (in Norwegian)
  Høgskolen i Agder, Kristiansand, Norway, March 2004

Research Visits

• Invited lecturer for the Vladikavkas young scientists mathematical school, XVI (online), September 24-27, 2021. Short Course Pre-Riesz Spaces (4 lectures)
• Research visit at Indian Institute of Technology Madras, Department of Mathematics, Chennai, India, February 19 - March 5, 2019
  Short Course for PhD students: An intruduction into partially ordered vector spaces: substructures and structure preserving operators
• CMO-BIRS Workshop Recent Advances in Banach Lattices
  Oaxaca, Mexico, from April 29 to May 09, 2018
• Research visit at the South. Mathematical Institute of Vladikavkaz Scientific Centre, Russian Academy of Sciences, North Ossetia, 24-30 May 2015, funded by the DFG Grant Positivity in Banach spaces
• Deputy professorship (W2) at University of Kassel, April - September 2012
• Research cooperation on partially ordered vector spaces and operators on ordered spaces with O. van Gaans, Leiden University (The Netherlands).
  Many joint work visits in Leiden and Dresden since 2005.
  In 2006 – 2010 the visits were supported by a 'VIDI subsidie' Stationary dynamics in infinite dimensions (639.032.510) in the 'Vernieuwingsimpuls' programme of the Netherlands Organization for Scientific Research (NWO).
• Short course for graduate students: Pre-Riesz Spaces: Disjointness, Ideals, Bands; National Technical University Athens, Department of Mathematics, Athens, Greece, March 2006. Visiting lecturer within the ERASMUS programme (teaching staff mobility).
• Research visit at St. Petersburg State University, Mathematics and Mechanics Faculty, Russia, October – December 1999

Co-organizer of Workshops and Conferences

• IWOTA 2024, 35th International Workshop on Operator Theory and its Applications, University of Kent, Canterbury, UK, August 12 - 16, 2024; Special Session: Positive operators and their dynamics, gemeinsam mit Jochen Glück

• Workshop on Ordered Vector Spaces and Positive Operators, Wuppertal, March 2023, together with Jochen Glück and Sahiba Arora

• DMV Annual Meeting FU Berlin, September 2022, Section Functional Analysis, Real and Complex Analysis, together with Agnes Radl

• Workshop on Ordered Banach Spaces, Positive Operators and Applications",
  TU Dresden, March 27-29, 2019,
  funded by the DFG Grant: Ordnungserhaltende Operatoren in Problemen der optimalen Steuerung und in der Theorie der partiellen Differentialgleichungen CH 1282/5-1.
• AIMS - International Conference on Dynamical Systems, Differential Equations and Applications, TU Dresden, May 2010.
  Special Session Positive Systems, together with T. Damm.
• Conference Positivity IV - Theory and Applications, TU Dresden, July 2005.

Selected Presentations on Conferences

• An order theoretical analysis of atomic JBW-algebras
  Positivity XI, Ljubljana, Slovenia, July 2023
• Pre-Riesz Spaces

  Workshop on Ordered Banach Spaces, Positive Operators and Applications,

  TU Dresden, Germany, March 2019
• Ideals and Bands in Pre-Riesz Spaces
  Positivity VIII, Southwest Jiaotong University, Chengdu, China, July 2015
• Directed Ideals in Partially Ordered Vector Spaces
  Positivity VII, Universiteit Leiden, The Netherlands, July 2013
• Disjointness Preserving Operators on pre-Riesz Spaces
  Operator semigroups meet complex analysis, harmonic analysis and mathematical physics. A symposium held in Herrnhut, Germany, June 2013
• Collatz-Wielandt Sets and Common Linear Lyapunov Functions for Positive Switched Systems
  POSTA 2012, Hamilton Institute, National University of Ireland, Maynooth, September 2012
• Characterization of Bands in Pre-Riesz Spaces by means of Functional Representation
  International Conference on Ordered Spaces and Applications, National Technical University of Athens, Greece, November 2011
• Robust Stability of Positive Linear Systems
  AIMS - International Conference on Dynamical Systems, Differential Equations and Applications, Dresden, May 2010
• Robustness of Positive Linear Systems
  Positivity VI, El Escorial, Madrid, Spain, July 2009
• Stability Radii for Positive Systems
  International Symposium on Positivity and its Applications in Science and Economics, Abant Izzet Baysal University Bolu, Turkey, September 2008
• Bands in Partially Ordered Vector Spaces
  Conference Positivity V, Queens University Belfast, UK, July 2007
• Disjoint Complements in Partially Ordered Vector Spaces
  Conference Positivity IV - Theory and Applications, TU Dresden, July 2005
• On Quasimonotone Increasing Operators on Ordered Normed Spaces
  Conference Function Spaces VII, Adam Mickiewicz University Poznan, Poland, July 2003
• Positive-off-diagonal Operators on Ordered Normed Spaces
  SAET Conference on Positivity, Rhodos, Greece, July 2003
• On a Special Class of Positively Invertible Operators
  Conference Function Spaces VI, Wroclaw University of Technology, Poland, September 2001
• On certain Maximum Principles for Positive Operators
  Conference Positivity and its Applications, Katholieke Universiteit Nijmegen, The Netherlands, July 2001