Replacing side-view mirrors in trucks with integrated digital system to improve safety (DREAMS)

Replacing rear-view mirrors on trucks by rear-view camera monitoring systems and in-vehicle monitors is expected to increase safety and reduce fuel consumption. This project generated knowledge on how such systems operate, if truck drivers find them useful and appealing, and to what extent they can improve traffic safety. Stoneridge’s camera-based rear-view mirror prototype mounted on a Scania truck served as a use case. The prototype includes cameras mounted close to the front corners of the truck cabin and in-vehicle monitors mounted in Apillars showing videos of the surroundings to truck drivers. An evaluation methodology has been developed and applied in tests at the test track AstaZero and on public roads. The evaluations involved both controlled and naturalistic experiments, as well as real-world use of the platform. These were conducted under various light and weather conditions and captured various traffic environments including urban, rural and highway driving. The evaluations showed that a high-level of safety and usability could be achieved, and provided valuable insights on further improvements of the prototype, which were later implemented within the project. A majority of the drivers found the prototype desirable and easy to get used to. The major safety advantages that they identified as compared to the conventional mirrors include: a) larger field of view, especially at intersections and roundabouts, b) direct visibility significantly improved, c) dirt from windshield does not affect visibility, and d) there is no need for body and head movements to increase field of view. Some of the drivers found that objects were too small on the monitors, especially on the passenger side, and that cameras reacted differently to different light sources. Some of the drivers expressed also a general anxiety for technical failures that may occur over the lifespan of the prototype. The project has also identified how expand the functionality of the prototype regarding driver support and automated driving. Several different concepts were suggested including: detection of vulnerable road users and other potential hazards in blind spots, free lane indication, estimation of distance to other vehicles and objects, and platoon monitoring. Examples of future research include further improvement of the prototype in terms of e.g., monitor placement and camera adaptability to different light sources, as well as further development and evaluation of the concepts providing additional functionality. The project was conducted by Stoneridge Electronics AB, Scania CV AB, and RISE Viktoria AB. It has increased technical maturity of Stoneridge’s camera-based rear-view mirror prototype and brought it closer to the market launch that is scheduled for 2018. It has also led to a general growth in innovation capacity in Sweden, and empowered strategic R&D activities and manufacturing in the country

The Isotopic Composition of Enriched Si: A Data Analysis

To determine the Avogadro constant by counting the atoms in quasi-perfect spheres made of silicon crystals highly enriched with 28Si, the isotopic composition of the crystal was measured in different laboratories by different measurement methods. This paper examines the consistency of the measurement results.JRC.DG.D.4-Isotope measurement

A Reassessment of the Molar Volume and of the Avogadro Constant.

Abstract not availableJRC.D-Institute for Reference Materials and Measurements (Geel

Present Status of the Avogrado Constant Determination from Silicon Crystals with Natural Isotopic Composition

The determination of the Avogadro Constant from selected silicon crystals is described. The density molar mass and lattice spacing of the 2 crystals were measured at NMIJ, PTB, IRMM, IMGC and NIST. When all date are combined, it leads to the Avogadro Constant of 6.022 135 3 (21) 10^23 mol^-1.JRC.D.4-Isotope measurement

Large-scale Production of Highly Enriched 28Si for the Precise Determination of the Avogadro Constant

An attempt is described to replace the present definition of the kilogram with the mass of a certain number of silicon atoms. A prerequisite for this is that the Avogadro constant, NA, is determined with a relative uncertainty of better than 2 × 10−8. For the determination, silicon crystals are used. However, the difficulty arising thereby is the measurement of the average molar mass of natural Si. Consequently, a worldwide collaboration has been launched to produce approximately a 5 kg 28Si single crystal with an enrichment factor greater than 99.985% and of sufficient chemical purity so that it can be used to determine NA with the targeted relative measurement uncertainty mentioned above. In the following, the first successful tests of all technological steps will be reported (enrichment of SiF4, distillation into silane and chemical purification, chemical vapour deposition of polycrystalline 28Si, floating zone growth of a dislocation-free single crystal) and new equipment for the production of high-purity 28Si with an enrichment of not less than 99.99% will be described. All steps are well defined by a Technical Road Map (TRM28) and all key results are measured by new mass spectrometric, IR spectroscopic and other chemical and physical methods, such as Hall effect, photoluminescence, laser scattering and x-ray topographic methods (TRM for Analytical Monitoring and Certification, TRM28-AMC). The initial enrichment of the gas is >0.999 95 and the depletion during the entire process is <0.000 05. The isotopic homogeneity is checked by natural Si crystal growth and does, in the enriched sphere, not exceed 5 × 10−10, relatively. The C content of the final material is less than 1015 atoms cm−3 and the specific resistance is 400–1000 _ cmJRC.D.4-Isotope measurement

Counting the Atoms in a 28Si Crystal for a New Kilogram Definition

This paper concerns an international research project aimed at determining the Avogadro constant by counting the atoms in an isotopically enriched silicon crystal. The counting procedure was based on the measurement of the molar volume and the volume of an atom in two 1 kg crystal spheres. The novelty was the use of isotope dilution mass spectrometry as a new and very accurate method for the determination of the molar mass of enriched silicon. Because of an unexpected metallic contamination of the sphere surfaces, the relative measurement uncertainty, 3 × 10-8 NA, is larger by a factor 1.5 than that targeted. The measured value of the Avogadro constant, NA = 6.022 140 82(18) × 1023 mol-1, is the most accurate input datum for the kilogram redefinition and differs by 16 × 10-8 NA from the CODATA 2006 adjusted value. This value is midway between the NIST and NPL watt-balance values.JRC.DG.D.4-Isotope measurement