The Supernova Remnant W44: confirmations and challenges for cosmic-ray acceleration

The middle-aged supernova remnant (SNR) W44 has recently attracted attention because of its relevance regarding the origin of Galactic cosmic-rays. The gamma-ray missions AGILE and Fermi have established, for the first time for a SNR, the spectral continuum below 200 MeV which can be attributed to neutral pion emission. Confirming the hadronic origin of the gamma-ray emission near 100 MeV is then of the greatest importance. Our paper is focused on a global re-assessment of all available data and models of particle acceleration in W44, with the goal of determining on a firm ground the hadronic and leptonic contributions to the overall spectrum. We also present new gamma-ray and CO NANTEN2 data on W44, and compare them with recently published AGILE and Fermi data. Our analysis strengthens previous studies and observations of the W44 complex environment and provides new information for a more detailed modeling. In particular, we determine that the average gas density of the regions emitting 100 MeV - 10 GeV gamma-rays is relatively high (n= 250 - 300 cm^-3). The hadronic interpretation of the gamma-ray spectrum of W44 is viable, and supported by strong evidence. It implies a relatively large value for the average magnetic field (B > 10^2 microG) in the SNR surroundings, sign of field amplification by shock-driven turbulence. Our new analysis establishes that the spectral index of the proton energy distribution function is p1 = 2.2 +/- 0.1 at low energies and p2 = 3.2 +/- 0.1 at high energies. We critically discuss hadronic versus leptonic-only models of emission taking into account simultaneously radio and gamma-ray data. We find that the leptonic models are disfavored by the combination of radio and gamma-ray data. Having determined the hadronic nature of the gamma-ray emission on firm ground, a number of theoretical challenges remains to be addressed.Comment: 13 pages, 11 figures, accepted by A&

Systematizing new value proposition through a TRIZ-based classification of functional features

AbstractIn recent years, several TRIZ practitioners have focused their attention on the application of TRIZ concepts for new business strategy definition. Among the others, the Blue Ocean Strategy has attracted the largest consensus. Nevertheless, this methodological approach proves to be very elegant to describe past business innovation successes, while it provides just general directions if a new profile of “values” is requested for a given product or service. The present paper analyzes with a TRIZ perspective 32 case studies from the BOS literature and shows that more prescriptive guidelines can be identified from these experiences

Development of an Equilibrium-based Model of Gasification of Biomass by Aspen Plus

Abstract Agricultural and forestry residues are usually processed as wastes; otherwise, they can be recovered to produce electrical and thermal energy through processes of thermochemical conversion, such us torrefaction, pyrolysis and gasification. Currently, the gasification of residual biomass for producing neutral CO 2 fuel for energy production is in development stage. In this context, this study proposes anequilibrium-based model, developed by the commercial software Aspen Plus, of a co-current gasifier fueled with agriculture residual, which allows estimating the chemical composition and theheating value of the syngas produced. The prediction of such model includes the main gaseous species, the yields of char and tar and describes the gasification process through the mass and energy balances, the water-gas shift (WGS) and the methanation reaction. The model validation was carried out through the comparison with experimental data, concerning two biomass with different moisture content and different gasification conditions, for sixteen cases compared. Overall, the comparison between the results of the simulations and the experimental data have shown a good agreement

Calibration of a Multichannel Water Vapor Raman Lidar through Noncollocated Operational Soundings: Optimization and Characterization of Accuracy and Variability

Abstract This paper presents a parametric automatic procedure to calibrate the multichannel Rayleigh–Mie–Raman lidar at the Institute for Atmospheric Science and Climate of the Italian National Research Council (ISAC-CNR) in Tor Vergata, Rome, Italy, using as a reference the operational 0000 UTC soundings at the WMO station 16245 (Pratica di Mare) located about 25 km southwest of the lidar site. The procedure, which is applied to both channels of the system, first identifies portions of the lidar and radiosonde profiles that are assumed to sample the same features of the water vapor profile, taking into account the different time and space sampling. Then, it computes the calibration coefficient with a best-fit procedure, weighted by the instrumental errors of both radiosounding and lidar. The parameters to be set in the procedure are described, and values adopted are discussed. The procedure was applied to a set of 57 sessions of nighttime 1-min-sampling lidar profiles (roughly about 300 h of measurements) covering the whole annual cycle (February 2007–September 2008). A calibration coefficient is computed for each measurement session. The variability of the calibration coefficients (∼10%) over periods with the same instrumental setting is reduced compared to the values obtained with the previously adopted, operator-assisted, and time-consuming calibration procedure. Reduction of variability, as well as the absence of evident trends, gives confidence both on system stability as well as on the developed procedure. Because of the definition of the calibration coefficient and of the different sampling between lidar and radiosonde, a contribution to the variability resulting from aerosol extinction and to the spatial and temporal variability of the water vapor mixing ratio is expected. A preliminary analysis aimed at identifying the contribution to the variability from these factors is presented. The parametric nature of the procedure makes it suitable for application to similar Raman lidar systems

Post-fire management of cork oak forests

28 páginas, 11 figuras.This chapter concerns the ecology and post-fire management of cork oak forests. It starts with a short overview of ecological and socio-economic context, continuing with an introduction on the cork oak post-fire regeneration strategies and the main factors affecting tree responses. Several post-fire management issues and alternatives, such as tree logging, assisting natural regeneration, reforestation, cork harvesting and pruning, or protecting against herbivory, are also presented and discussed.To all people who contributed in some way to the contents of this chapter, with special thanks to Francisco Rego, Paulo Fernandes and Thomas Curt. To Fundação para a Ciência e a Tecnologia (PhD grant SFRH/BD/65991/2009), FFP (project Recuperação de Áreas Ardidas), EU (COST FP0701 and TRANZFOR), and the Spanish government (project VARQUS, CGL2004-4325/BOS).Peer reviewe