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For a number of years surgeons have been using robotic arms to carry out precision operations. These technical appendages can operate without any tremors, and according to the manufacturers, they off er up to ten times the precision of the human hand. The downside is that surgeons using robot arms cannot feel what they are doing. Until now,that is. Countless research groups are looking into the possibilities of force feedback, i.e. transmitting the reaction force acting on the robot arm back to the surgeon. A lot of progress has already been made with soft structures, but hard structures remained a problem. Researchers at TU Delft have succeeded in building a fi rst prototype that can grasp both hard and soft structures while enabling the remotely operating surgeon to really feel what he is doing.

Fingerprinting is an essential tool to shun legal buyers of digital content from illegal redistribution. In fingerprinting schemes, the merchant embeds the buyer's identity as a watermark into the content so that the merchant can retrieve the buyer's identity when he encounters a redistributed copy. To prevent the merchant from dishonestly embedding the buyer's identity multiple times, it is essential for the fingerprinting scheme to be anonymous. Kuribayashi and Tanaka, 2005, proposed an anonymous fingerprinting scheme based on a homomorphic additive encryption scheme, which uses basic quantization index modulation (QIM) for embedding. In order, for this scheme, to provide sufficient security to the merchant, the buyer must be unable to remove the fingerprint without significantly degrading the purchased digital content. Unfortunately, QIM watermarks can be removed by simple attacks like amplitude scaling. Furthermore, the embedding positions can be retrieved by a single buyer, allowing for a locally targeted attack. In this paper, we use robust watermarking techniques within the anonymous fingerprinting approach proposed by Kuribayashi and Tanaka. We show that the properties of an additive homomorphic cryptosystem allow for creating anonymous fingerprinting schemes based on distortion compensated QIM (DC-QIM) and rational dither modulation (RDM), improving the robustness of the embedded fingerprints. We evaluate the performance of the proposed anonymous fingerprinting schemes under additive-noise and amplitude-scaling attacks.

Is it possible to make platinum particles with a diameter of less than eight nanometres? That was the question Jan Marijnissen at the aerosol lab of Delft ChemTech was asked. Together with graduate student Jan van Erven, the famous aerosol expert Sheldon Friedlander of the University of California (UCLA), and the University of Karlsruhe, Germany, Marijnissen set out to experiment. He managed to do achieve this by using his favourite electrospray method. While they were at it, the research teams used an electron microscope to see how a soot filter uses the platinum nanogranules to get rid of its soot.

As many viewers will know from experience, the thrilling description on a video cover offers no guarantee of suspense in the video itself. The exciting bits may add up to only a few minutes of the 90 minutes or so running time, and that is something you would have liked to have known in advance. Dr. Alan Hanjalic at the Information Technology and Systems (its) faculty of Delft University of Technology has collaborated with Dr. Li-Qun Xu of British Telecom to develop a method that will let a computer analyse the video content for suspense, melancholy, mirth, or any mix of these emotions.On top of this the Delft researcher has been working on a system that will automate access to video archives. Over the years, film and television companies have built up enormous archives. The Dutch Audiovisual Archive alone contains some 900,000 hours of analogue audiovisual material. The only way to make this material accessible is to look at the video frames, make a record of what you see, and store the record in a computer. Hanjalics system can classify video stills as well as moving video frames. It can pick Editors always have to dig into the image archives to put together documentaries, or to illustrate television news stories. Television companies have masses of video material at their disposal. The archives keep on growing so that locating the right bit of footage on people who are not in the news daily is becoming more and more difficult. It can pick out the goals in a soccer match with no trouble at all. News broadcasts are automatically cut into sections and arranged according to subject.