The Profitability Of The U.S. Food Supply Chain: Financial Indicators, Cross-Section And Time-Series Effects

This study examines the U.S. agribusiness’ profitability from 1986 to 2008. By using regression analysis, we model accounting returns as a function of diverse financial indicators. To select the explanatory variables we further decompose the DuPont equation and perform some ad hoc transformations to model return on investment (rather than return on equity). In addition, using a two-way fixed effects model, we test within sectors and time effects of returns. We compare time effects with the three most recent economic recessions

Métaheuristiques pour la classification de bouchons naturels en liège

We study heuristic methods for a classification problem encountered in cork industry. More precisely, we want to optimize the parameters of the classification rule that is daily used to classify corks. We experimented several metaheuristics and compared their performance on a real test case. The obtained results improve the current classification rate. We propose also, from our observations, new directions that may lead to further improvement for a still better classification.

The Gould's Belt Very Large Array Survey III. The Orion region

We present results from a high-sensitivity (60 $\mu$Jy), large-scale (2.26 square degree) survey obtained with the Karl G. Jansky Very Large Array as part of the Gould's Belt Survey program. We detected 374 and 354 sources at 4.5 and 7.5 GHz, respectively. Of these, 148 are associated with previously known Young Stellar Objects (YSOs). Another 86 sources previously unclassified at either optical or infrared wavelengths exhibit radio properties that are consistent with those of young stars. The overall properties of our sources at radio wavelengths such as their variability and radio to X-ray luminosity relation are consistent with previous results from the Gould's Belt Survey. Our detections provide target lists for followup VLBA radio observations to determine their distances as YSOs are located in regions of high nebulosity and extinction, making it difficult to measure optical parallaxes.Comment: Accepted for publication in ApJ; 51 pages, 15 figures, 5 table

Wetting, interfacial interactions and sticking in glass/steel systems

Wetting and sticking of soda-lime glass on two types of stainless steel as well as on platinum and vitreous carbon substrates are studied in a neutral gas atmosphere between 860 and 1200degreesC. Wetting is measured by the "transferred drop" version of the sessile drop technique, enabling fully isothermal spreading kinetics to be monitored. Sticking is investigated by measuring the temperature of glass drop detachment from the substrate during cooling below the vitreous transition temperature. Characterization of substrate and glass surfaces after separation is carried out using surface profilometry, atomic-force microscopy (AFM) and scanning electron microscopy (SEM) with energy-dispersive X-ray (EDX) spectroscopy. The character of molten glass wetting on metal (reactive or non-reactive) and the type of interactions ensuring ultimate wetting and adhesion (physical or chemical) are identified and discussed. The factors controlling glass spreading kinetics and those governing glass/steel sticking are also evidenced. (C) 2004 Elsevier B.V. All rights reserved

Decay Constants of Heavy-Light Mesons

The decay constants of the heavy-light pseudoscalar mesons are studied in a high statistics run using the Wilson action at $\beta=6.0$ and $\beta=6.2$, and the clover action at $\beta=6.0$. The systematics of $O(a)$ discretisation errors are discussed. Our best estimates of the decay constants are: $f_D$ = 218(9) MeV, $f_D/f_{Ds}$ = 1.11(1) and we obtain preliminary values for $f_B$.Comment: at the Dallas Lattice Conference, October 1993. 3 pages in a single postscript file, uuencoded form. Rome Preprint 93/98

Detection of ultra-high energy cosmic ray showers with a single-pixel fluorescence telescope

We present a concept for large-area, low-cost detection of ultra-high energy cosmic rays (UHECRs) with a Fluorescence detector Array of Single-pixel Telescopes (FAST), addressing the requirements for the next generation of UHECR experiments. In the FAST design, a large field of view is covered by a few pixels at the focal plane of a mirror or Fresnel lens. We report first results of a FAST prototype installed at the Telescope Array site, consisting of a single 200 mm photomultiplier tube at the focal plane of a 1 m$^2$ Fresnel lens system taken from the prototype of the JEM-EUSO experiment. The FAST prototype took data for 19 nights, demonstrating remarkable operational stability. We detected laser shots at distances of several kilometres as well as 16 highly significant UHECR shower candidates.Comment: Accepted for publication in Astroparticle Physic