Damping of very soft moving quarks in high-temperature QCD

We determine the analytic expression of the damping rates for very soft moving quarks in an expansion to second order in powers of their momentum in the context of QCD at high temperature. The calculation is performed using the hard-thermal-loop-summed perturbation scheme. We describe the range of validity of the expansion and make a comparison with other calculations, particularly those using a magnetic mass as a shield from infrared sensitivity. We discuss the possible occurrence of infrared divergences in our results and argue that they are due to magnetic sensitivity.Comment: 24 pages, REVTe

Neural network applications to reservoirs: Physics-based models and data models

International audienceEditoria

Approche Strategique pour Rentabilite Economique du Coton dans la Commune de Banikoara au Benin: la Cuma comme une Response Alternative?

Avec une production qui ne cesse de croître depuis 2016, le coton place actuellement le Bénin au rang du premier pays producteur du coton en Afrique. Pour maintenir cette tendance profitable à l’économie nationale, il est nécessaire de la rendre plus rentable aux producteurs, surtout avec la mise en œuvre de réformes visant la mécanisation de l’agriculture. C’est ce qui justifie cette étude ayant pour centre d’intérêt, la rentabilité économique de la production du coton, avec comme cadre expérimental, la localité de Banikoara, qui en est le premier producteur au plan national. L’objectif visé est de faire une analyse de la rentabilité économique du coton dans un contexte d’investissement en matériel de production. La méthode de direct costing a servi de modèle économique pour cet exercice qui a mis en exergue les stratégies d’association de cultures, de financement partiel de l’équipement sur emprunt et de promotion des CUMA (Coopérative d’Utilisation de Matériel Agricole). Au regard des résultats obtenus, on observe que la mise en œuvre de ces stratégies assure une rentabilité certaine aux producteurs.   With production that has continued to grow since 2016, cotton currently ranks Benin as the leading cotton-producing country in Africa. To maintain this profitable trend for the national economy, it is necessary to make it more profitable for producers, especially with the implementation of reforms aimed at the mechanization of agriculture. This is what justifies this study whose focus is the economic profitability of cotton production, with the experimental setting of the locality of Banikoara, which is the leading producer at the national level. The objective is to analyze the economic profitability of cotton in the context of investment in production equipment. The direct costing method served as an economic model for this exercise which highlighted the strategies of association of cultures, partial financing of equipment on loan and promotion of CUAE (Cooperative for the Use of Agricultural Equipment). In view of the results obtained, we observe that the implementation of these strategies ensures a certain profitability for the producers

Horticultural Households Profit Optimization and the Efficiency of Labour Contract Choice

In agriculture, the coexistence of different forms of land tenancy or labour contract has been explained so far by several theories related to Marshallian inefficiency, incentives, risk sharing, and transaction costs, including supervision costs. These theories and the empirical evidences have greatly contributed to explain the reasons behind land tenancy or labour contract choice. This study follows up on this. Moreover, it intends to take a further step by focusing particularly on the production technologies at plot level, and by designing and testing a theoretical model based on household profit optimization. This model will take into account the supervision costs of labour (i) to compare optimum profit derived from plots based on household labour, a sharecropping labour contract, and a wage labour contract, controlling for irrigation equipment (ii) to test the efficiency of the labour contract choice using data from Senegal’s horticultural zone. As expected, the production elasticity of labour decreases when improved irrigation equipment like a motor pump is used. The technology displays an increasing return to scale on plots without a motor pump and a constant return to scale on plots irrigated with a motor pump. While on plots without a motor pump the sharecropping contract is the efficient labour contract choice, leading to a higher optimum profit for the household, on plots irrigated with a motor pump, the wage contract is the best labour contract choice. Consequently, we can conclude from this finding that the use of a motor pump drives out the sharecropping contract in favour of household labour and the wage labour contract.land tenancy, labour, sharecropping, wage, contract, supervision, household, profit optimization, efficient, irrigation equipment, horticulture, Senegal, Agricultural Finance,

Tourisme et Croissance Inclusive au Bénin: Une Analyse d’Après l’Indice Synthétique de Croissance Inclusive

Cette étude vise à examiner le type de relation entre tourisme et croissance inclusive au Bénin de 1995 à 2021 en utilisant comme variable dépendante, contrairement à plusieurs études,  l’Indice Synthétique de Croissance Inclusive  (ISCI). En nous appuyant sur des données chronologiques, nous avons effectué des estimations à l'aide du Modèle Vectoriel à Correction d'Erreur (VECM), du test de causalité de Granger et du Modèle à Correction d'Erreur (MCE) sous STATA 15. Les résultats révèlent une relation significative positive entre le ratio des recettes touristiques réelles et l'Indice Synthétique de Croissance Inclusive (ISCI), démontrant que le tourisme contribue à la croissance inclusive jusqu'à un certain seuil. En outre,  la nature bidirectionnelle de cette relation (entre tourisme et croissance inclusive) a été également mise en évidence.   This study aims to examine the type of relationship between tourism and inclusive growth in Benin from 1995 to 2021 using as a dependent variable, unlike several studies, the Synthetic Inclusive Growth Index (ISCI). Based on historical data, we carried out estimations using the Vector Error Correction Model (VECM), the Granger causality test and the Error Correction Model (ECM) under STATA 15. The results reveal a significant positive relationship between the ratio of real tourism receipts and the Synthetic Inclusive Growth Index (ISCI), demonstrating that tourism contributes to inclusive growth up to a certain threshold. Furthermore, the bidirectional nature of this relationship (between tourism and inclusive growth) was also highlighted

Tourisme et Croissance Inclusive au Bénin : Une Analyse d’Après l’Indice Synthétique de Croissance Inclusive

Cette étude vise à examiner le type de relation entre tourisme et croissance inclusive au Bénin de 1995 à 2021 en utilisant comme variable dépendante, contrairement à plusieurs études, l’Indice Synthétique de Croissance Inclusive (ISCI). En nous appuyant sur des données chronologiques, nous avons effectué des estimations à l'aide du Modèle Vectoriel à Correction d'Erreur (VECM), du test de causalité de Granger et du Modèle à Correction d'Erreur (MCE) sous STATA 15. Les résultats révèlent une relation significative positive entre le ratio des recettes touristiques réelles et l'Indice Synthétique de Croissance Inclusive (ISCI), démontrant que le tourisme contribue à la croissance inclusive jusqu'à un seuil donné. En outre, la nature bidirectionnelle de cette relation (entre tourisme et croissance inclusive) a été également mise en évidence. This study aims to examine the type of relationship between tourism and inclusive growth in Benin from 1995 to 2021 using as a dependent variable, unlike several studies, the Synthetic Inclusive Growth Index (ISCI). Based on historical data, we carried out estimations using the Vector Error Correction Model (VECM), the Granger causality test and the Error Correction Model (ECM) under STATA 15. The results reveal a significant positive relationship between the ratio of real tourism receipts and the Synthetic Inclusive Growth Index (ISCI), demonstrating that tourism contributes to inclusive growth up to a given threshold. Furthermore, the bidirectional nature of this relationship (between tourism and inclusive growth) was also highlighted

Tourisme et Croissance Inclusive au Bénin: Une Analyse d’Après l’Indice Synthétique de Croissance Inclusive

Cette étude vise à examiner le type de relation entre tourisme et croissance inclusive au Bénin de 1995 à 2021 en utilisant comme variable dépendante, contrairement à plusieurs études,  l’Indice Synthétique de Croissance Inclusive  (ISCI). En nous appuyant sur des données chronologiques, nous avons effectué des estimations à l'aide du Modèle Vectoriel à Correction d'Erreur (VECM), du test de causalité de Granger et du Modèle à Correction d'Erreur (MCE) sous STATA 15. Les résultats révèlent une relation significative positive entre le ratio des recettes touristiques réelles et l'Indice Synthétique de Croissance Inclusive (ISCI), démontrant que le tourisme contribue à la croissance inclusive jusqu'à un certain seuil. En outre,  la nature bidirectionnelle de cette relation (entre tourisme et croissance inclusive) a été également mise en évidence.   This study aims to examine the type of relationship between tourism and inclusive growth in Benin from 1995 to 2021 using as a dependent variable, unlike several studies, the Synthetic Inclusive Growth Index (ISCI). Based on historical data, we carried out estimations using the Vector Error Correction Model (VECM), the Granger causality test and the Error Correction Model (ECM) under STATA 15. The results reveal a significant positive relationship between the ratio of real tourism receipts and the Synthetic Inclusive Growth Index (ISCI), demonstrating that tourism contributes to inclusive growth up to a certain threshold. Furthermore, the bidirectional nature of this relationship (between tourism and inclusive growth) was also highlighted

Identification of weed population and determination of plant performance in aerobic rice under different rates of NPK application / Wan Nur Aifa Wan Din

Rice is as a staple food that consumed daily by the people. Aerobic rice was produced through crossing technique in between the traditional upland, which is drought tolerance and improved lowland, which is high yield. Application of fertilizer in aerobic rice has been proved as one of the factors affected plant growth and development, hence, lead to produce optimum yield. However, attainment of effectiveness of nutrient supply is rely on the different rates of fertilizer application. Glasshouse study in Randomized Complete Block Design (RCBD) was conducted at Greenhouse University Technology MARA (UiTM) Jasin. This experiment was carried out to determine the influence of various NPK levels, which are 3gram, 6gram and 9gram towards weed population infestation and to evaluate the growth performance of aerobic rice (AERON 1) such as plant height, number of tiller and chlorophyll content upon different sampling dates. Leptochloa chinensis was found as predominant weed species in all treatments followed by Fimbristylis miliacea, Cleome rutidosperma, Cassia occidentallis and Ludwigia hyssopifolia. Besides that, plant heights, number of tillers and chlorophyll contents for AERON 1 were recorded highest in the treatment of 9gram NPK fertilizer

Experimental Study on Dynamic Responses of Truss Spar Platform Subjected To Long-Crested Waves and Short-Crested Waves with Current

The environmental conditions e.g. wave and current are the important aspects that shall be considered in the design of offshore structures. Research have been highlighted on the long-crested waves or unidirectional wave. However, the occurrence of such waves are seldom found in the real sea condition [1]. Studies also stated that wave force by long-crested waves would be overestimated or overdesigned [2]. On the other hand, short-crested wave would be better representing the real sea condition. By considering short-crested waves, an optimum design of the offshore structure with cost and time effectiveness could be achieved [2]. Yet, there no experimental studies has been reported comparing the dynamic responses of truss spar platform subjected to long-crested and short-crested wave with current in six degree of freedom. Thus, an experimental study by wave tank test has been performed in order to quantify the effectiveness of the dynamic responses of the truss spar platform subjected to short-crested waves by comparing to the long-crested waves with current. A model of truss spar platform which is fabricated by steel plate with 1:100 ratio scale from the prototype was used in the study of dynamic responses. In wave tank test, long-crested waves with current and short-crested waves with current was generated by wave and current generator. Spreading function, cosine squared (cos2) was implemented and incorporated with JONSWAP spectrum to produce short-crested wave. Current as well has been considered in this study. Wave probe was adopted to record the wave profile while the Qualisys Track Manager (QTM) was used to record the dynamic motion responses in six degree of freedom. The dynamic motion responses of truss spar platform model were compared among the long and short-crested waves with current. As results, the responses of truss spar considering short-crested waves with current were found to smaller compare to long-crested wave with current. This indicated that offshore structure design considering short-crested waves with current could the optimized and provide an economical design