Search results for "Tributi"

Ash resuspension related to the 2011–2012 Cordón Caulle eruption, Chile, in a rural community of Patagonia, Argentina

2017

Abstract The 2011–2012 Cordon Caulle eruption emitted about 1 km3 of rhyodacitic tephra. Dominant westerly winds in the region caused most of the primary tephra to deposit in neighboring Argentina. In addition to the impact of widespread dispersal and fallout of primary tephra during the eruption, Argentina was also significantly affected by remobilization of the primary ash even several years after the climactic phase of the eruption. In this mixed methods study, we combine aspects of natural and social sciences to characterize the ash resuspension events associated with the 2011–2012 Cordon Caulle deposits and assess the impacts on the Argentinian farming community of Ingeniero Jacobacci …

New Data on Orthotrichum gigantosporum Lewinsky (Orthotrichaceae, Bryophyta), a Widespread Northern Andean-Patagonian Endemic Moss

2021

The moss family Orthotrichaceae is still poorly known in the southern extreme of South America. This is especially true regarding the morphological variability, geographical distribution, and ecological affinities of the species restricted to the Andean-Patagonian area. These deficiencies are addressed for Orthotrichum gigantosporum Lewinsky, one of the least known and most interesting endemics of the area. After examining the rich collections made by our team in southern Chile and Argentina, we have found numerous new localities for the species. Orthotrichum gigantosporum has proven to be a widespread moss in the forests and scrublands of the northern sector of the Andean-Patagonian area. …

Reasons of irregularity of seed's distribution in the divider heads of air-seeders

2017

ISBN : 978-3-18-092300-0; International audience; Modern seeding equipment must allow to cultivate sizeable areas efficiently and finalize the seeding in a short amount of time. Air-seeder is a solution for a fast seeding: seeds are conveyed from the high-capacity seed hopper to the coulter-bar by an air-stream. Taking into account the complexity of this type of seed drills, they stay little-studied. Few developments have been done on divider headers responsible of distribution accuracy. This paper deals with a study on the influence of divider head geometry and functioning conditions on the seed's distribution accuracy. Moreover, observation of the seed's behaviour is done using a high-spe…

The MLE of the mean of the exponential distribution based on grouped data is stochastically increasing

2016

This paper refers to the problem stated by Balakrishnan et al. (2002). They proved that maximum likelihood estimator (MLE) of the exponential mean obtained from grouped samples is stochastically ordered provided that the sequence of the successive distances between inspection times is decreasing. In this paper we show that the assumption of monotonicity of the sequence of distances can be dropped.

Income Distribution and Consumption Patterns in a 'Classical' Growth Model

2003

Spatially dependent parton distribution functions and hard processes in nuclear collisions

2014

First measurement of the Sivers asymmetry for gluons using SIDIS data

2017

The Sivers function describes the correlation between the transverse spin of a nucleon and the transverse motion of its partons. It was extracted from measurements of the azimuthal asymmetry of hadrons produced in semi-inclusive deep inelastic scattering of leptons off transversely polarised nucleon targets, and it turned out to be non-zero for quarks. In this letter the evaluation of the Sivers asymmetry for gluons in the same process is presented. The analysis method is based on a Monte Carlo simulation that includes three hard processes: photon-gluon fusion, QCD Compton scattering and leading-order virtual-photon absorption process. The Sivers asymmetries of the three processes are simul…

Forward light-by-light scattering and electromagnetic correction to hadronic vacuum polarization

2023

Lattice QCD calculations of the hadronic vacuum polarization (HVP) have reached a precision where the electromagnetic (e.m.) correction can no longer be neglected. This correction is both computationally challenging and hard to validate, as it leads to ultraviolet (UV) divergences and to sizeable infrared (IR) effects associated with the massless photon. While we precisely determine the UV divergence using the operator-product expansion, we propose to introduce a separation scale $\Lambda\sim400\;$MeV into the internal photon propagator, whereby the calculation splits into a short-distance part, regulated in the UV by the lattice and in the IR by the scale $\Lambda$, and a UV-finite long-di…

Challenges in Geographically Distributed Information System Development : A Case Study

2021

Geographically distributed information system development (ISD) projects are more and more common, especially among organisations operating in global markets. Distributed ISD yields potential competitive advantages by developing new products near the target markets, utilizing global labour markets, and exposing the organisation to innovations, ideas and new paradigms. However, distributed ISD also presents challenges and problems which organisations must take into consideration. The pivotal challenge is usually communication. People working on the same project in different locations find it difficult to communicate due to lack of formal and informal face-to-face communication, different wor…

Features of W production in p-p, p-Pb and Pb-Pb collisions

2017

We consider the production of inclusive W bosons in variety of high-energy hadronic collisions: p--p, p--$\overline{\rm p}$, p--Pb, and Pb--Pb. In particular, we focus on the resulting distributions of charged leptons from W decay that can be measured with relatively low backgrounds. The leading-order expressions within the collinearly factorized QCD indicate that the center-of-mass energy dependence at forward/backward rapidities should be well approximated by a simple power law. The scaling exponent is related to the small-$x$ behaviour of the quark distributions, which is largely driven by the parton evolution. An interesting consequence is the simple scaling law for the lepton charge as…