Research Scientist

Pulp and Paper Research Institute of Canada
570 Boulevard St. Jean
Pointe-Claire, Quebec H9R 3J9
CANADA

At PAPRICAN, I was a member of the Product Performance Program. I specialized on statistical models of paper structure and the fracture mechanics of heterogeneous fibre materials.

The goal of my work was to identify physical parameters that control the quality of paper products. For example, paper breaks have a significant economic impact on the operation of pressrooms and paper machines.  A better understanding of the fracture process in paper can lead to practices for minimizing the occurrence of breaks.

  • I developed a dynamic model of paper transport to investigate tension variations in paper webs, and studied the dependence of the strength uniformity parameter on various parameters. This work led to the publication (Hristopulos and Uesaka, 2002), which won the 2003 Johannes A. Van den Akker Prize for Advances in Paper Physics.
  • I used geostatistical methods based on random field theories and stochastic geometry to model paper structure and to analyze mill databases.
  • My research helped to identify critical parameters for paper breaks and factors that control the strength reliability of paper products.

Research Assistant Professor

Department of Environmental Sciences and Engineering University of North Carolina at Chapel Hill
Chapel Hill, NC 27599-7400

At Chapel Hill, I was a member of the Center for the Advanced Study of the Environment (CASE).
I collaborated with George Christakos, Marc Serre, and Casey Miller. I also benefited from informal discussions with Markus Hilpert.

My research at CASE focused on applications of statistical physics and field theory in environmental processes and heterogeneous porous media

Atmospheric and subsurface environmental processes are characterized by spatial and temporal variability that can be modeled mathematically by means of random fields.

Similarly, porous media (natural and technological), have heterogeneities at various physical scales, which influence their macroscopic (large-scale) behavior. More specifically:

  • I developed theoretical and computational methods (FORTRAN, MATLAB) with applications in geostatistics and porous media (structure, flow and transport).
  • I investigated applications of geostatistical methods in the characterization of environmental pollutant concentrations. This research has applications in the estimation and prediction of various risk factors in different environmental media.
  • Another direction of my research focused on the solution of stochastic differential equations that govern the subsurface flow and transport of groundwater contaminants. These problems have important applications in environmental fluid mechanics and enhanced oil recovery. In particular, I developed methods based on field theory for calculating large-scale features of flow fields that incorporate statistical information about the fine-scale variations due to the heterogeneity.