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LUCIFER (LBT NIR-Spectroscopic Utility with Camera and Integral-Field Unit for Extragalactic Research) is a full cryogenic NIR spectrograph and imager (λ 0.9μ - 2.5μ, zJHK-bands) to be built by a consortium of five institutes (Landessternwarte Heidelberg (LSW), Max Planck Institut fuer Astronomie in Heidelberg (MPIA), Max Planck Institut fuer Extraterrestrische Physik (MPE) in Garching, Astronomisches Institut der Ruhr Universitaet Bochum (AIRUB) and Fachhochschule fuer Technik und Gestaltung (FHTG) in Mannheim). The instrument has been selected as one of three first-light instruments for the Large Binocular Telescope (LBT) on Mt. Graham, Arizona which first mirror becomes available to the community in early 2003. The second mirror and a second more or less identical spectrograph/imager follows 18 month later. Both LUCIFER instruments will be mounted at the bent Gregorian foci of the two individual LBT-mirrors and include six observing modes: seeing and diffraction limited imaging, seeing and diffraction limited longslit spectroscopy, seeing limited multi-object spectroscopy (MOS) and integral-field spectroscopy (IFU). The detector will be a Rockwell HAWAII-2 HgCdTe-array with a pixel-size of 18μ.

In an ever faster changing world, innovation is a crucial tool to maintain the quality of road networks. In order to safely use innovative materials and techniques, validation procedures are needed. Because of the variable and non-standard nature of innovations, it is hard to standardize this kind of validation. Also, ensuring that innovations address the needs of road authorities can be quite a challenge. The Dutch highway authority, Rijkswaterstaat, currently uses a three tier approach to the validation of innovations. These consists of solicited innovations to address specific agency challenges and two systems to address unsolicited innovations. This paper describes the need for innovations, the most urgent topics that require solutions in the Dutch situation, the current approach towards innovation validation including examples of all three types of validation and the further developments foreseen for that system.

In order to adequately characterize the fatigue response of the various membranes with surrounding multilayer surfacing layers on orthotropic steel decks and collect the necessary parameters for FE modeling, the details of the cyclic Membrane Adhesion Tester (MAT) are introduced. The fatigue damage in membrane interface is related to the amount of dissipated work computed by using the measurement of actuator load and piston deformation during the loading cycle. The dissipated work, which is equivalent to the lost part of the total potential energy of the membrane, has been utilized to explain the incremental damage during the testing. Furthermore, using the experimental data obtained from MAT, ranking of the bonding characteristics of various membrane products is demonstrated as well as the role of other influencing factors, such as the types of substrate and test temperatures.

Self-concept and utility-values are thought to influence differences in choices, participation and performance in schools-careers between students of different genders and ages. This study was investigating existence of gender differences in such constructs regarding science. Further, the study investigated whether development of such constructs is still influenced by how children feel their parents perceive them in relation to sciences. Using a 30-item, Lickert-type questionnaire, data were collected from a random sample of 184 second and third graders. Results showed that, students’ self perceptions and those of parents regarding science are positively related. Further, self-concept and utility-values were higher among boys than girls. Based on the result, it was concluded that, parents’ gender-based perceptions regarding science that are still communicated at home might be the reason for the development of children’s gender-based self-perceptions regarding sciences.

Het is ondoenlijk om voor elk nieuw stofje in bronnen voor drinkwater testen uit te voeren om na te gaan hoe dit stofje het beste verwijderd zou kunnen worden. Mogelijk bieden nieuwe rekenkundige methoden, waarmee staCsCsch verbanden tussen bijvoorbeeld eigenschappen en gedrag van een stof worden berekend (QSAR’s), hier uitkomst. QSAR’s staan nog in de kinderschoenen; er is nog veel validaCe nodig en dat vereist weer heel veel goed gedocumenteerde data. KWR verkent de mogelijkheden om al deze data in een internaConale database te gaan verzamelen.

In order to adequately characterize the fatigue response of the various membranes with surrounding multilayer surfacing layers on orthotropic steel decks and collect the necessary parameters for FE modeling, the details of the cyclic Membrane Adhesion Tester (MAT) are introduced. The fatigue damage in membrane interface is related to the amount of dissipated work computed by using the measurement of actuator load and piston deformation during the loading cycle. The dissipated work, which is equivalent to the lost part of the total potential energy of the membrane, has been utilized to explain the incremental damage during the testing. Furthermore, using the experimental data obtained from MAT, ranking of the bonding characteristics of various membrane products is demonstrated as well as the role of other influencing factors, such as the types of substrate and test temperatures.

Polaire stoffen, zoals medicijnen of drugs, worden steeds vaker aangetroffen in het milieu. Het aantal stoffen en hun concentraties zullen in de toekomst nog hoger worden door de vergrijzing. Drugs en medicijnen zijn moeilijk uit het water te zuiveren. Experimenten laten zien dat nieuwe materialen, zoals gefunctionaliseerde polymeren, mogelijkheden bieden voor de zuivering van water voor de drinkwaterbereiding.

The French five-point bending test (5PBT) provides a laboratory scale test that allows studying the fatigue resistance of surfacing systems on orthotropic steel deck bridges (OSDB). The surfacing structure for OSDB in the Netherlands consists mostly of multilayer system: top porous asphalt layer, guss asphalt layer, steel deck and two membrane layers. In this paper, an analytical solution for 5PBT setup is presented first. In order to better understand the influence of geometrical, mechanical and structural parameters on the performance of the typical multilayer surfacing system of OSDB in the Netherlands, the 5PBT specimens with five structural layers have been investigated. The parametric study is performed at the numerical platform CAPA-3D that was developed at the Section of Structural Mechanics of TU Delft. The thicknesses of the top porous asphalt layer, middle guss asphalt layer and the steel plate are varied. The influences of the mechanical properties of both top and bottom membrane layers are studied. The sensitivities of those influence factors are evaluated by the examination of the maximum tensile stress at the top surface of the porous asphalt layers and the strain distributions through the entire thickness of the specimen at two cross sections.

Due to lightweight and flexibility, orthotropic steel deck bridges become popular the last decades but several problems were reported in relation to asphalt surfacing materials such as rutting, cracking, loss of bond between the surfacing system and steel deck. In the Netherlands a surfacing structure for orthotropic steel bridge decks mostly consists of five structural layers: top porous asphalt layer, guss asphalt layer, steel deck and two membrane layers. The five-point bending fatigue test is the standard device in France for asphalt concrete used on steel orthotropic deck bridges to perform the best asphalt mixture having a strong resistance to cracking. For the needs of this paper the 5 PBT was employed in order to evaluate the performance of the whole multilayer structure on steel deck and also to evaluate the mechanical properties of both top and bottom membrane and the influence they have on the structure. For the completion of the experimental investigation two types of specimen have been tested using the 5PBT set up. Displacement sensors have been used in order to detect the initiation of cracks where they are most likely to appear. Strain gauges have been used in order to monitor significant changes in strain on the Guss asphalt layer during the fatigue tests. Shear displacements between the asphalt layers are monitored and presented. It shows that the stiffness and the bonding characteristics of the intermediate membrane sheet as well as the wearing course behaviour seem to have great influence on the mechanical response of multilayer bridge surfacing system.

In order to adequately characterize the adhesive bonding strength of the various membranes with surrounding materials on orthotropic steel decks and collect the necessary parameters for FE modeling, details of the Membrane Adhesion Test (MAT) are introduced. Analytical constitutive relations of the MAT device have been derived using the same methodology as Williams (1997). Furthermore, using the experimental data obtained from MAT, ranking of the bonding characteristics of various membrane products is demonstrated as well as the role of other influencing factors, such as the types of substrate and test temperatures.

A base of data on tyre/road noise levels was compiled and attempts were made to synthesize ageing rates for various types of pavement. Noise data had been recorded by CPX trailers or by vehicle pass-by measurements. Ageing rates expressed as a noise level increase in dB per year of pavement age based on these types of measurement were compared. Pavement ageing models including both pavement age and traffic load were derived. A widespread was seen in data from apparently identical situations. With the same type and age of pavement there was a wide scatter in measured noise levels. Combining traffic load and pavement age in multiple parameter models did not improve correlations, so the pavement age is most important. The paper summarizes typical ageing rates found for some types of pavement and gives advice on how future investigations of pavement acoustic ageing could be designed.

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This paper presents the design, implementation, and evaluation of the RFID Guardian, the first-ever unified platform for RFID security and privacy administration. The RFID Guardian resembles an ``RFID firewall,'' that monitors and controls access to RFID tags by combining a standard-issue RFID reader with unique RFID tag emulation capabilities. Our system provides a platform for both automated and coordinated usage of RFID security mechanisms, offering fine-grained control over RFID-based auditing, key management, access control, and authentication capabilities. We have prototyped the RFID Guardian using off-the-shelf components, and our experience has shown that active mobile devices are a valuable tool for managing the security of RFID tags in a variety of applications, including protecting low-cost tags that are unable to regulate their own usage.More philosophically, RFID technology vividly illustrates the difficulties of security administration in a world of increasingly pervasive, decentralized, low-cost, and low-power computing. Our paper thus also offers a glimpse of what system administration may be like in the future, when laymen face the responsibility to manage systems of tiny computers that they are barely aware of.