Test set-up in 50 metre long corridor at NMi in Delft.
Laser distance measuring in air has been brought to its penultimate level: 100 metres at micrometer accuracy.
At first, the task seemed simple enough,” says Dr Nandini Bhattacharya (Applied Sciences), who co-supervised Dr Moxi Cui’s PhD research on distance metrology. Previously Dr Bas Swinkels had developed laser metrology in the same group with a different kind of laser. A new ‘femtosecond laser’ was expected to perform even better, producing ultra-short pulses of light (40 microns long) separated by 15 centimetres of nothing. Distance can be measured by splitting the laser beam: one part is sent down the distance to be measured, gets reflected and then returns; the other part bounces on a moveable reflector situated nearby. A pulse counter provides an estimate of (twice) the distance in multiples of 15 centimetres. Overlaying the pulses from both arms and bringing them into interference was expected to lower the precision to the order of the light wavelength (0.4 micron). Continued…
Posted in Articles, Delta.
Tagged with distance, laser, metrology.
By admin
– oktober 14, 2010
Mark van Staalduinen discovered paper's fingerprint - Photo: Tomas van Dijk
The imprint of the sieve in traditionally manufactured paper may be used to verify the authenticity of a work of art.
How to establish if the print of an etching by Rembrandt dates from say 1640, during his lifetime, or from hundred years later, if, as is the case for most of his prints, the paper doesn’t carry a watermark?
A new technology presented this week in a PhD thesis by Mark van Staalduinen offers an alternative identification method for handmade or ‘laid’ paper. The technique works by analyzing the pattern of the horizontal and vertical wires that form the imprint from the sieve that the paper was made in. This pattern is so unique that it can be regarded as the paper’s fingerprint: it links the sheet to a certain manufacturer during a relatively short time period (because the sieves became progressively deformed in the paper-making process, they were not used for long periods of time). Continued…
Posted in Articles, Delta.
Tagged with art history, image analysis, paper.
By admin
– oktober 7, 2010
Ir. Roy Zuijderduin:" Such cables wil be replaced by supercondutors". (Photo: Tomas van Dijk)
High voltage researchers last week announced a breakthrough in the development of a superconducting transmission cable.
The Delft high voltage laboratory collaborates with the German-Danish power cable producer NKT in the development of a high temperature superconducting (HTS) power cable. The superconducting cable should replace one of the existing 6 kilometre long transmission cables connecting the centre of Amsterdam with a distribution point further north. Continued…
Posted in Articles, Delta.
Tagged with HTS cables, power transmission, superconduction.
By admin
– september 30, 2010
A new material featuring a big temperature jump when subjected to a magnetic field will enable competitive magnetic cooling.
Hotel minibars are probably the first market to adopt magnetic cooling on a large scale. These machines currently use silent but very inefficient thermoelectric Peltier cooling. Replacing those machines by equally silent magnetocaloric fridges would save lots of energy, while adding to the hotel’s green credentials.
Continued…
Posted in Articles, Delta.
Tagged with cooling, magnetism, magnetocaloric effect.
By admin
– september 30, 2010
Steven van Campen showing his digital gubbe - Photo: Tomas van Dijk
In disaster training, the maximum number of victims should be helped with the limited means available. The iPod-based victims that Steven van Campen developed will actually ‘die’ when not properly cared for.
Even the biggest disaster relief operations usually start with a phone call from an eyewitness, someone reporting a collision on a motorway, for example. But once in the scene, the accident turns out to be a massive pile-up, including a leaking patrol truck, a van transporting radioactive materials and, wedged in between, a family car with injured but still-alive children in the backseat. Continued…
Posted in Articles, Delta.
Tagged with disaster training, iPod, serious gaming.
By admin
– september 23, 2010
Delft researchers succeeded in substantially prolonging an electron spin’s quantum state by using microwave pulses to shield it from surrounding perturbations.
Dr. Ronald Hanson and Gijs de Lange from the Kavli Institute of Nanoscience (Applied Sciences) had a busy day last Friday. On Thursday, the article they co-authored with researchers from the Ames Lab (U.S. Department of Energy) was published in Science magazine. Almost immediately colleagues from all over the world began mailing and phoning to pass on their congratulations. “Our finding has opened up a whole new field of research”, Dr. Hanson says. Continued…
Posted in Uncategorized.
By admin
– september 17, 2010
Akira Endo visiting the Apex telescope in Chile at an altitude of 5100 metres. (Photo: Wilfred Frieswijk)
Dr. Akira Endo has been awarded a Veni grant to develop a detector for studying the evolution of the early universe.
“Smaller galaxies combine by colliding. Stars and gas mix in a violent process, creating new stars and adding mass to the black hole in the centre.” Astronomer and physicist Akira Endo describes the processes as if he had witnessed them himself. Continued…
Posted in Articles, Delta.
Tagged with astronomy, asttron, galaxies, sub-millimetre.
By admin
– september 9, 2010
HafenCity Hamburg: living on a dike. (Photo: Luidger, Wikicommons)
Increasing rainfall levels will force most Dutch riverside cities to augment their flood defences. Why not improve the urban quality at the same time, asks PhD student Bianca Stalenberg. Continued…
Posted in Articles, Delta.
Tagged with flood defences, urban development.
By admin
– september 2, 2010
Enkhuizen and Friesland viewed from the balloon. (Photo: Tim Zaman)
TU Delft student Tim Zaman successfully completed a remarkable hobby project. Last summer he launched a helium balloon loaded with cameras and controls.
August 1, early afternoon on the Afsluitdijk. On a strip of land situated between the Waddenzee and IJsselmeer, a small, blue Volkswagen drives in a northeasterly direction toward Friesland. Tim Zaman (22) sits in the back with a laptop on his knees. He is studying the gps-tracks on the screen while giving directions to a friend driving the car. Zamans girlfriend films their adventure from the passenger’s seat. Continued…
Posted in Articles, Delta.
Tagged with aerial photography, balloon.
By admin
– augustus 27, 2010
Delft Outlook, July 2010
In recent months, the new Bionanoscience department (part of the faculty of Applied Sciences) led by Professor Cees Dekker has gone against the prevailing trend by recruiting top researchers to take part in a broad research programme examining how living cells actually work.
Click image for .pdf download
Continued…
Posted in Delft Outlook.
Tagged with bionano science.
By admin
– juli 10, 2010
