Search

The major objective of the deliverable is to present the traffic surveillance algorithms designed within COLOMBO. The deliverable gives an overview of existing conventional traffic surveillance approaches, first, which are mainly relying on stationary detectors. In a second step, this document places the algorithms developed in COLOMBO in the scope of already existing V2X-based surveillance algorithms. The document shows four different solutions for traffic surveillance, namely: • Cluster-based Traffic Surveillance • DissFlow Traffic Surveillance • Traffic State Generation from CAMs • Probe Vehicle Data-based Traffic Surveillance The document additionally outlines the on-going work on traffic anomalies detection and local emissions monitoring and presents an overview on the costs of V2X-based systems.

A revised formula for calculation of dose per time or monitor unit ("dose rate") of irregular megavoltage photon beams is proposed. The formula considers additionally the shading by secondary shieldings of the plane source describing the scattered radiation in the head. Therefore, in addition to the primary output factor C(ac) as function of the equivalent square ac x ac of the collimator field size a secondary output factor S(as) is introduced denoted as function of the equivalent square as x as of the irregular field. S is determined using a satellite diaphragm formed of shielding blocks in combination with a totally opened collimator. In this definition, S includes both the effects of radiation scattered in tissue (phantom scatter factor PSF) and of missing photons from the plane source by the blocks (satellite diaphragm factor SAT). In the usual formula to calculate the "dose rate" (output) at reference point in depth t, PSF is replaced by S: D = D0 x C(ac) x [PSF(as)/PSF(ac)] x T x R(as,t). There T is representing the block tray factor and R(as,t) the tissue phantom ratio or relative depth dose, depending on the irradiation technique used. Thus the modified formula is given by D = D0 x C(ac) x [S(as)/S(ac)] x T x R(as,t). Measurements show that the revised formula provides an additional precision of up to 2% in the calculation of dose, depending on the type of accelerator respectively on the size of the plane source of scattered radiation.

The neutron dose was measured in X-ray beams with a limiting energy of 8 to 45 MeV and in 42 MeV electrons (10 X 10 cm2) from several electron accelerators (betatrons, linear accelerators, microtron). The measurements were taken with activation probes and nuclear films of polycarbonate coated with 0,5 mm Cd. On a 42 MeV betatron, the neutron spectrum, the density of neutron flow and the neutron dose of the central ray were evaluated in a paraffin phantom by means of seven threshold value reactions. The neutron spectrum showed only a small dependence on depth. The neutron equivalent dose (with Q approximately equal to 10) was 13 mSv at the surface per Gy of the absorbed dose of 42 MeV X-rays in the dose maximum. The neutron dose contribution to the dose maximum was only a little higher and showed a curve resembling to the depth dose curve of X-radiation. In case of 42 MeV electrons, the neutron equivalent dose was 0,8 mSv per Gy of the electron dose at the surface of the phantom. The measurements taken by means of nuclear films showed a monotonous increase of the equivalent dose contribution of fast neutrons from 0,8 mSv in case of 8 MeV to 15 mSv in case of 45 MeV X-rays per Gy of the primary radiation dose in the dose maximum. The increase became lower above 25 MeV and was not dependent on the field size or on measurements with or without phantom.

Vorstellung des COLOMBO-Systems zur Reduktion der Emissionen im Straßenverkehr unter Verwendung von Fahrzeug-Fahrzeug- und Fahrzeug-Infrastruktur-Kommunikation bei geringen Ausrüstungsraten.