Search results for " Mathematica"
showing 10 items of 689 documents
Climate and agriculture: empirical evidence for countries and agroecological zones of the Sahel
2022
International audience; ow heterogenous is the impact of climate change across space and the type of agricultural production? In this paper, we investigate the relationship between climate change and variability, measured by temperature and rainfall, and agricultural production at the country and agroecological zone levels of the Sahel. We consider a crop production index and five cereals (maize, millet, sorghum, wheat and rice). Based on an original climate database and an agricultural production function estimated for the period 1961–2016, we show that average rainfall and temperature during the growing season indeed have highly heterogeneous effects on agricultural production, depending …
Comparison between simulated and observed LHC beam backgrounds in the ATLAS experiment at E beam =4 TeV
2018
Results of dedicated Monte Carlo simulations of beam-induced background (BIB) in the ATLAS experiment at the Large Hadron Collider (LHC) are presented and compared with data recorded in 2012. During normal physics operation this background arises mainly from scattering of the 4 TeV protons on residual gas in the beam pipe. Methods of reconstructing the BIB signals in the ATLAS detector, developed and implemented in the simulation chain based on the FLUKA Monte Carlo simulation package, are described. The interaction rates are determined from the residual gas pressure distribution in the LHC ring in order to set an absolute scale on the predicted rates of BIB so that they can be compared qua…
On Mathematical Thought, 1
2012
Taking into account some basic epistemological considerations on Psychoanalysis by Igna-cio Matte Blanco, it is possible to deduce some first simple remarks on certain logical as-pects of schizophrenic reasoning. Further remarks on mathematical thought are also made in the light of what established, taking into account the comparison with the extreme patho-logical schizophrenic paradigm.
REINSTATEMENT OF THE DINOFLAGELLATE GENUS Tripos TO REPLACE Neoceratium, MARINE SPECIES OF Ceratium (DINOPHYCEAE, ALVEOLATA)
2013
Morphological and molecular data support the split at the genus level of the marine and freshwater species of the dinoflagellate Ceratium (Gonyaulacales, Dinophyceae). A new genus name Neoceratium F. Gomez, D. Moreira & P. Lopez-Garcia was proposed for the marine species. However, it is considered illegitimate (type species is type of Biceratium Vanhoffen), and the nomenclatural priority is here given for the genus Tripos Bory (type species Tripos muelleri ) which replaces Neoceratium . New combinations are proposed for the existing names of species and infraspecific taxa. Reinstalacion del genero de dinoflagelados Tripos para reemplazar a Neoceratium , especies marinas de Ceratium (Dinophy…
A branch-and-cut algorithm for the Team Orienteering Problem
2017
The Team Orienteering Problem aims at maximizing the total amount of profit collected by a fleet of vehicles while not exceeding a predefined travel time limit on each vehicle. In the last years, several exact methods based on different mathematical formulations were proposed. In this paper, we present a new two-index formulation with a polynomial number of variables and constraints. This compact formulation, reinforced by connectivity constraints, was solved by means of a branch-and-cut algorithm. The total number of instances solved to optimality is 327 of 387 benchmark instances, 26 more than any previous method. Moreover, 24 not previously solved instances were closed to optimality.
Economic Robustness Analysis of Adaptive Chart Schemes for Monitoring the Total Nonconformities Number in Inspection Units
2015
In recent years, a variety of enhanced schemes for the c chart have been developed aimed at the effectiveness improving of the related statistical process control (SPC) procedures. However, the performance of such chart schemes can be very sensitive to values assumed for some operating and cost parameters, in particular to the considered process shift magnitude arising from out-of-control conditions. In such a circumstance, the effectiveness of such chart schemes can be subjected to substantial reductions when they are implemented in operative contexts given that, in practice, such value is unknown and it can be very difficult to accurately estimate. For this reason, in the present paper i…
Les études hédoniques soutiennent-elles une valeur verte élevée dans le bâtiment ? Une réponse par la méta-analyse
2018
International audience; La place majeure occupée par le secteur du bâtiment dans la consommation d'énergie (40%) et les émissions de gaz à effet de serre (1/3 des émissions) explique le développement du débat scientifique axé sur la réduction de l'impact environnemental du bâtit et sur ses leviers. Ces dernières années ont notamment vu croitre une littérature considérable relative à la disposition à payer du public pour les bâtiments « verts » labélisés par des écolabels, cette « valeur verte » étant estimée dans la grande majorité des études via des modèles hédoniques. Dans cet article, nous proposons d'offrir une synthèse de ces résultats dans le cadre d'une méta-analyse portant sur plus …
Wastewater modification processes in a stabilization reservoir: a new mathematical model
2018
The paper presents a mathematical model for the simulation of the ecology of a wastewater stabilization reservoir (WSR). WSRs are hypertrophic aquatic systems devoted to water storage in warm countries where shortage conditions are often encountered. Several factors that affect the stabilization reservoir’s effluent quality were taken into account: hydraulics and hydrology, solar radiation, reaeration, algae, zooplankton, organic matter, pathogens, and sediment-water interactions. The model quantifies the specific influence of each factor on effluent quality, and evaluating the correlation between the different factors. State variables included in the model were: algae, dissolved oxygen, or…
Networked Analysis of a Teaching Unit for Primary School Symmetries in the Form of an E-Book
2021
In mathematics education, technology offers many opportunities to enrich curricular contents. Plane symmetries is a topic often skipped by primary teachers. However, it is important and may be worked in attractive ways in dynamic geometry software environments. In any regular classroom there are students with different levels of mathematical attainment, some needing easy tasks while others, particularly mathematically-gifted students, need challenging problems. We present a teaching unit for plane symmetries, adequate for upper primary school grades, implemented in a fully interactive electronic book, with most activities solved in GeoGebra apps. The book allows student to choose which itin…
Emergent ultrafast phenomena in correlated oxides and heterostructures
2017
The possibility of investigating the dynamics of solids on timescales faster than the thermalization of the internal degrees of freedom has disclosed novel non-equilibrium phenomena that have no counterpart at equilibrium. Transition metal oxides (TMOs) provide an interesting playground in which the correlations among the charges in the metal $d$-orbitals give rise to a wealth of intriguing electronic and thermodynamic properties involving the spin, charge, lattice and orbital orders. Furthermore, the physical properties of TMOs can be engineered at the atomic level, thus providing the platform to investigate the transport phenomena on timescales of the order of the intrinsic decoherence ti…