Fossil and Non-Fossil Sources of Different Carbonaceous Fractions in Fine and Coarse Particles by Radiocarbon Measurement

Radiocarbon offers a unique possibility for unambiguous source apportionment of carbonaceous particles due to a direct distinction of non-fossil and fossil carbon. In this work, particulate matter of different size fractions was collected at 4 sites in Switzerland to examine whether fine and coarse carbonaceous particles exhibit different fossil and contemporary sources. Elemental carbon (EC) and organic carbon (OC) as well as water-soluble OC (WSOC) and water-insoluble OC (WINSOC) were separated and determined for subsequent 14C measurement. In general, both fossil and non-fossil fractions in OC and EC were found more abundant in the fine than in the coarse mode. However, a substantial fraction (~20 ± 5%) of fossil EC was found in coarse particles, which could be attributed to traffic-induced non-exhaust emissions. The contribution of biomass burning to coarse-mode EC in winter was relatively high, which is likely associated to the coating of EC with organic and/or inorganic substances emitted from intensive wood burning. Further, fossil OC (i.e. from vehicle emissions) was found to be smaller than non-fossil OC due to the presence of primary biogenic OC and/or growing in size of wood-burning OC particles during aging processes. 14C content in WSOC indicated that the second organic carbon rather stems from non-fossil precursors for all samples. Interestingly, both fossil and non-fossil WINSOC concentrations were found to be higher in fine particles than in coarse particles in winter, which is likely due to primary wood burning emissions and/or secondary formation of WINSOC.

Vehicular traffic surveillance and road lane detection using radar interferometry

Speed enforcement on public roadways is an important issue in order to guarantee road security and to reduce the number and seriousness of traffic accidents. Traditionally, this task has been partially solved using radar and/or laser technologies and, more recently, using video-camera based systems. All these systems have significant shortcomings that have yet to be overcome. The main drawback of classical Doppler radar technology is that the velocity measurement fails when several vehicles are in the radars beam. Modern radar systems are able to measure speed and range between vehicle and radar. However, this is not enough to discriminate the lane where the vehicle is driving on. The limitation of several vehicles in the beam is overcome using laser technology. However, laser systems have another important limitation: They cannot measure the speed of several vehicles simultaneously. Novel video-camera systems, based on license plate identification, solve the previous drawbacks, but they have the problem that they can only measure average speed but never top-speed. This paper studies the feasibility of using an interferometric linear frequency modulated continuous wave radar to improve top-speed enforcement on roadways. Two different systems based on down-the-road and across-the-road radar configurations are presented. The main advantage of the proposed solutions is they can simultaneously measure speed, range, and lane of several vehicles, allowing the univocal identification of the offenders. A detailed analysis about the operation and accuracy of these solutions is reported. In addition, the feasibility of the proposed techniques has been demonstrated with simulations and real experiments using a Ka-band interferometric radar developed by our research group.

An initial assessment of the literature on the measurement, control, transport, transformation and health effects of urregulated diesel engine emissions /

Final report, January 1979.

Review of chest deflection measurement techniques and transducers. Final report.

National Highway Traffic Safety Administration, Office of Research and Development, Washington, D.C.

Lap belt angle measurement in adjustable rear seats: procedure development and vehicle survey. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Sobering agent: effectiveness measurement and development. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Calibration of a six-degree-of-freedom acceleration measurement device. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Vehicle crashworthiness and aggressiveness. Volume II: Measurement of aggressiveness for safety standards compliance.

Mode of access: Internet.

Model minimum performance specifications for lidar (laser) speed measurement devices.

Mode of access: Internet.

Measurement of vehicle contamination by exhaust gases. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

Analysis of performance measurement and training requirements for driving decision making in emergency situations. Final report.

National Highway Traffic Safety Administration, Washington, D.C.

An investigation of site effects on roadside measurement of truck noise. Final report.

Transportation Department, Office of Noise Abatement, Washington, D.C.

Development of standards and tests for acceptance of traffic signal lenses. Final report.

Federal Highway Administration, Washington, D.C.

Mobile parametric measurement device. Volume II: test procedures. Users manual.

National Highway Traffic Safety Administration, Washington, D.C.

New concepts for traffic barrier systems. Final report.

Federal Highway Administration, Structures and Applied Mechanics Division, Washington, D.C.