Active Travel Co-Benefits of Travel Demand Management Policies that Reduce Greenhouse Gas Emissions, MTI Report 12-12

There is increasing evidence that improved health outcomes may be significant co-benefits of land use plans and transport policies that increase active transport (or walking and biking for purposeful travel) and reduce greenhouse gas emissions (GHGs) from vehicle miles traveled (VMT). A greater understanding of these benefits may broaden the constituency for regional planning that supports local and national GHG reduction goals. In this study, California’s activity-based travel demand model (ABM) is applied to (1) demonstrate how this new generation of travel models can be used to produce the active travel data (age and sex distributions) required by comparative risk assessment models to estimate health outcomes for alternative land use and transport plans and to (2) identify the magnitude of change in active travel that may be possible from land use, transit, and vehicle pricing policies for California and its five major regions for a future 2035 time horizon. The results of this study suggest that distance-based vehicle pricing may increase walking by about 10% and biking by about 17%, and concurrently GHG from VMT may be reduced by about 16%. Transit expansion and supportive development patterns may increase active travel by about 2% to 3% for both walk and bike modes while also reducing VMT by about 4% on average. The combination of all three policies may increase time spent walking by about 13% and biking by about 19%, and reduce VMT by about 19%

Transportation Futures: Policy Scenarios for Achieving Greenhouse Gas Reduction Targets, MNTRC Report 12-11

It is well established that GHG emissions must be reduced by 50% to 80% by 2050 in order to limit global temperature increase to 2°C. Achieving reductions of this magnitude in the transportation sector is a challenge and requires a multitude of policies and technology options. The research presented here analyzes three scenarios: changes in the perceived price of travel, land-use intensification, and increases in transit. Elasticity estimates are derived using an activity-based travel model for the state of California and broadly representative of the U.S. The VISION model is used to forecast changes in technology and fuel options that are currently forecast to occur in the U.S., providing a life cycle GHG forecast for the road transportation sector. Results suggest that aggressive policy action is needed, especially pricing policies, but also more on the technology side. Medium- and heavy-duty vehicles are in particular need of additional fuel or technology-based GHG reductions

The impact of terrigeneous inputs on the Bay of Ouinne (New Caledonia) phytoplankton communities : a spectrofluorometric and microscopic approach

The impact of terrigeneous inputs on the phytoplankton composition was studied during a 2.5 months daily survey in the Bay of Ouinne, a deep cove on the south-eastern coast of New Caledonia. Surface waters benefited from nutrients originating from nearby land drainage and the Ouinne river outflow during periods of heavy rain. The nutrient composition mirrored the composition of the drained soils, with concentrations reaching 3-4 mu M for nitrate and 0.13 mu M for phosphate at the river mouth. In addition to nutrient inputs, significant quantities of particulate matter (inorganic and organic compounds) were discharged into the lagoon during heavy rain periods, resulting in transitory decreases of the photic layer depth and enrichments of the water column through remineralization processes. Changes in contributions of the main phytoplankton groups in response to terrigeneous inputs were shown by chlorophyll and phycobiliprotein spectrofluorometric analyses. While dry periods were marked by the dominance of pico-(Prochlorococcus, and high-phycourobilin (PUB) Synechococcus) and microcyanobacteria (Trichodesmium spp.), developments of various eukaryote populations resulted from land drainage occurring during the wet periods. This was indicated by the increase of accessory chlorophyll pigments that doubled at a depth of 15 m: chlorophyll b (chlorophytes), chlorophyll c(1) + c(2) (associated with diatoms and dinoflagellates), chlorophyll c(3) (associated with c(1) and/or c(2) in prymnesiophytes, chrysophytes and/or pelagophytes). In addition, Synechococcus with a high phycoerythrobilin (PEB) content also appeared to be stimulated by river outputs. Finally, microscopic observations of the > 35 mu m net plankton confirmed the greater presence of diatoms and dinoflagellates during periods of rain compared to Trichodesmium, particularly in the surface layer. (c) 2005 Elsevier Ltd. All rights reserved

Cocoa Butter Saturated with Supercritical Carbon Dioxide: Measurements and Modelling of Solubility, Volumetric Expansion, Density and Viscosity

International audienceThe use of supercritical carbon dioxide technology for lipid processing has recently developed at the expense of traditional processes. For designing new processes the knowledge of thermophysical properties is a prerequisite. This work is focused on the characterization of physical and thermodynamic properties of CO2-cocoa butter (CB) saturated mixture. Measurements of density, volumetric expansion, viscosity and CO2 solubility were carried out on CB-rich phase at 313 and 353 K and pressures up to 40 MPa. The experimental techniques have previously been compared and validated. Density measurements of CB and CB saturated with CO2, were performed using the vibrating tube technology at pressures ranging from 0.1 to 25 MPa. Experimental values correlated well with the modified Tait equation. CO2 solubility measurements were coupled to those of density in the same pressures ranges. At 25 MPa, the solubility of CO2 is 31.4 % and 28.7 % at 313 and 353 K. Phase behaviour was investigated using a view cell in order to follow the expansion of the CB-rich phase with the rise in pressure. Volumetric expansion up to 47 % was measured and correlated to the CO2 solubility. Phase inversion was observed at 313 K and 40 MPa. Lastly, we developed an innovative falling ball viscometer for high pressure measurements. Viscosity measurements were carried out up to 25 MPa showing a viscosity reduction up to 90 % upon CO2 dissolution. These results were correlated with two empirical models. A new model here presented, was favourably compared with the Grunberg and Nissan model. All the experimental results are consistent with the available literature data for the CB-CO2 mixture and other fat systems. This work is a new contribution to the characterization of physical and thermodynamic behaviour of fats in contact with CO2 which is necessary to design supercritical fluid processes for fats processing

A laser triggered electron source for pulsed radiolysis

We present the design of a photo-injector based accelerator for pulsed radiolysis applications. This machine is destined to meet the needs of the physical chemistry community at the Universite de Paris XI. A 4 MeV Energy electron pulse of a few picoseconds duration and with a charge in the range of 1 to 10 nC is produced from a Cs/sub 2 /Te photocathode. The photocathode is placed in the half energy spread cell of a 1-1/2 cell, 3 GHz RF gun, whose design is based on the gun used for the drive beam of the CERN CLIC Test facility. A 4 cell "booster" cavity is then used to accelerate the beam to an energy of 9 MeV. The transport system consists of a quadrupole triplet downsteam of the booster, two rectangular, 30 degree bend, dipoles with a pair of quadrupoles between them and a second triplet downstream of the second dipole. Energy dependent path length effects in the two dipoles allow the possibility of magnetic bunch compression depending on the phase-energy correlation of the bunch exiting the booster cavity. The beam envelope and the bunch length have been calculated through the transport line using TRACE-3d and PARMELA. These codes allow us to verify the required beam parameters at the experimental areas. We discuss the adjustment of the optics, aimed at producing the minimum electron bunch length at the experimental targets. (4 refs)

Swelling of Transported Smoke from Savanna Fires over the Southeast Atlantic Ocean

We use the recently released Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) Version 4.1 (V4) lidar data to study the smoke plumes transported from Southern African biomass burning areas. Significant improvements in the CALIPSO V4 Level 1 calibration and V4 Level 2 algorithms lead to a better representation of their optical properties, with the aerosol subtype improvements being particularly relevant to smoke over this area. For the first time, we show evidence of smoke particles increasing in size, evidenced in their particulate color ratios, as they are transported over the South Atlantic Ocean from the source regions over Southern Africa. We hypothesize that this is due to hygroscopic swelling of the smoke particles and is reflected in the higher relative humidity in the middle troposphere for profiles with smoke. This finding may have implications for radiative forcing estimates over this area and is also relevant to the ORACLES field mission

Swelling of Transported Smoke from Savanna fires over the Southeast Atlantic Ocean

We use the recently released Version 4 (V4) lidar data products from CALIPSO to study the smoke plumes transported from Southern African biomass burning areas. The significant improvements in CALIPSO V4 Level 1 calibration and the V4 Level 2 aerosol subtyping algorithms, the latter being particularly relevant to biomass burning smoke over this area, lead to a better representation of their optical properties. For the first time, we show evidence of smoke particles increasing in size, evidenced in their particulate color ratios, as they are transported over the South Atlantic Ocean from the source regions over Southern Africa. This is likely due to hygroscopic swelling of the smoke particles and is reflected in the higher relative humidity in the middle troposphere for profiles with smoke. This finding may have implications for radiative forcing estimates over this area and is relevant to the ORACLES field mission that is currently underway

Three Corner Sat Constellation - New Mexico State University: Communications, LEO Telecommunications Services, Intersatellite Communications, and Ground Stations and Network

The Three Corner Satellite Constellation is part of the AFOSRlDARP A University Nanosatellite program. This project is a joint effort among Arizona State University (ASU), University of Colorado at Boulder (CU), and New Mexico State University (NMSU). The constellation will consist of three identical nanosatellites, that will demonstrate stereo imaging, innovative command and data handling, and formation flying with RF communications and a possibility of cellular phone communications through LEO telecommunications satellites. To achieve mission objectives, the satellites in the constellation and the ground communications network will need to be designed as a cooperative communications and control network that will allow the satellites in the constellation to form a virtual formation. In this paper, we will present the necessary communications and control architecture for the space segment and the ground segment to form this virtual formation that are NMSU\u27s responsibility in the program. Companion papers describe the respective areas of responsibility of the other partners: ASU -Project Management; Electrical Power System; Structures, Mechanisms, Thermal, and Radiation; Attitude/Orbit Determination and Control; Micropropulsion experiment; and • Integration; CU -- Command & Data Handling, Distributed Operations, Stereoscopic Imaging, Science Operations, and Spacecraft Operations

Surface plasmons of metallic surfaces perforated by nanoholes

Recent works dealt with the optical transmission on arrays of subwavelength holes perforated in a thick metallic film. We have performed simulations which quantitatively agree with experimental results and which unambiguously evidence that the extraordinary transmission is due to the excitation of a surface-plasmon-polariton (SPP) mode on the metallic film interfaces. We identify this SPP mode and show that its near-field possesses a hybrid character, gathering collective and localised effects which are both essential for the transmission.Comment: 16 pages, 4 figure