Older projects
Before joining the Alaska Satellite Facility I carried out a number of research projects that are summarized here.
Delft Interfaculty Research Centre (DIOC)
During my post-doctoral research I was part of a program on "Determination
and prediction of the 3D-movements of the Earth's surface".
Within this program I worked on a project on "High-resolution monitoring
of deformation using SAR interferometry". The main goal of the project was
to develop data processing and validation strategies for InSAR for the monitoring
of three-dimensional movements of the Earth's surface over long time scales under
real conditions.
The research I carried out within this project focused on the optimization of a minimum cost flow phase unwrappingn algorithm. As part of this research I published a review paper on phase unwrapping:
Synergy of remotely sensed data
"Synergy of remotely sensed data" was a three-year research project supported by the European Scientific Research Network. It dealt with image and data fusion techniques and applications, and related synergistic use of disparate remote sensing data sets. There were eleven organizations involved in this project. Some 30 scientists from four European countries, and from many disciplines (ranging from physicists through electronic engineers, photogrammetrists, to foresters, geologists, geographers, landuse specialists) all tackled the same research issues from their own perspectives.
This was the project that provided the funding for my Ph.D. research. The project resulted in a final report as well as Craig Cassells' and my Ph.D. thesis.
Fusetutor
Fusetutor is a multimedia tutorial on remote sensing image and data fusion, consisting of seven chapters. It describes the concepts of data fusion and provides the technical background of three different levels of data fusion (pixel-based, feature-based and decision-based). Two case studies are included to show practical applications of the different fusion techniques. A glossary of terms, a list of relevant literature as well as a list of Internet links are given as appendices.
This was one of the most challenging project I have worked on. Initially, I covered all aspects of projects from writing the contents, to creating the graphics material and implementing it in the multimedia software under a particularly tight time line. At a later stage I had the support of Zoltán Vekerdy and Anupma Prakash for working on the case studies and the image processing. Despite a low budget covering only four months of time we pulled this project off. From my point of view, this was a master piece of team work.
Later, a second version of the tutorial was generated with more chapters and case studies. The results of the project are published under
BCRS InSAR
There were two BCRS InSAR project I was involved with. The first entitled "Deformation measurements with SAR" focused on application of this technique in Groningen, the Netherlands, where land subsidence is caused by the extraction of natural gas. As the subsidence is as low as less the one centimeter per year and the temporal decorrelation due to crop growth and climatic conditions is high, a standard InSAR technique did not suffice. An alternative approach combining leveling and InSAR measurements by means of a simple polynomial model, that describes the time and spatial dependence of the deformation, was used. This approach reduced the necessity for frequent leveling measurements, leaning to a better cost-benefit ratio than a technique based on leveling alone.
The second project investigated land subsidence caused by underground coal mining and coal mine fires. The test area was in Northwest China and the results achieved are documented in the final report as well as in a refereed journal paper cited below.