HAL-CIRAD
Not a member yet
54841 research outputs found
Sort by
Integrated, multi-scale and multi-objective design of batch food processing plants. Part 1: Methodology
No full textInternational audienceThe design of batch food processing plants is complex which requires the use of advanced simulation and optimisation methods. This paper presents how existing methods for multi-scale design and multi-objective optimisation can be combined together while carrying out the integrative design of these complex systems. To implement the Methodology for the Integrated, Multi-scale and Multi-Objective Design of Systems (MIMMODS), 8 tasks must be completed. The goal of the first 6 tasks is to build a design support tool that (i) simulates the behavior of the processing plant and estimates its performance at different functional levels and whatever design variables it is made up of, (ii) takes into account the preferences of the decision-maker to convert the performances of a design solution into desirability indices and (iii) searches for the design solution(s) that best satisfies the design objectives and the preferences of the decision-maker. When the design support tool is functioning, the results have to be visualised and analysed in order to validate whether the resulting design solution is satisfactory, realistic, feasible and consistent or whether a new iteration of the methodology needs to be conducted to refine the design support tool
Le potentiel d'une taxe sur le capital pour traiter la triple crise climatique
No full textInternational audienceThe triple climate inequality crisis, or in contributions, impacts and capacity to act within and between countries,is a central issue in addressing climate change. This Comment advocates for progressive wealth taxation as a viable solution to the finance gap
Retrieving Soil Moisture from Sentinel-1: Limitations over Certain Crops and Sensitivity to the First Soil Thin Layer
No full textInternational audienceThis paper presents a comparison between the Sentinel-1 (S1)/Sentinel-2 (S2)-derived soil moisture products at plot scale (S2MP) and in situ soil moisture measurements at a 10 cm depth for several winter and summer crops. Specifically, the paper discusses the consistency between the in situ soil moisture measurements, usually performed at a 10 cm soil depth, and the variable S1 C-band penetration depth in soil due to soil humidity conditions, vegetation development and S1 acquisition configuration. The aim is to provide end users with the strength and limitations of S1-derived soil moisture, mainly the S2MP soil moisture product, for their further applications. Both the estimated and measured soil moisture (SM) were evaluated over three testing fields in a Mediterranean climatic context, with crop cycles including wheat, tomato, cover crops and soybeans. The main results showed that the comparison between the S2MP-estimated SM based on S1 backscattering (at ~5 cm depth) with a 10 cm in situ SM is not always relevant during the crop cycle. In dry conditions, the S1 SM significantly underestimated the 10 cm SM measurements with an underestimation that could reach around 20 vol.% in some extremely dry conditions. This high underestimation was mainly due to the difference between the topsoil SM captured by the S1 sensor and the 10 cm in depth SM. Moderately wet conditions due to rainfall or irrigation showed less of a difference between the S1-estimated SM and the 10 cm in situ SM and varying between −10 and −5 vol.% due to the homogeneity of the SM at different soil depths. For extremely wet conditions, the S1 SM started to underestimate the SM values with an underestimation that can reach an order of −10 vol.%. A comparison of the S1-estimated SM as a function of the vegetation development showed that, for the studied crop types, the S1 SM estimates are only valid for low and moderate vegetation cover with a Normalized Difference Vegetation Index (NDVI) of less than 0.7. For dense vegetation cover (NDVI > 0.7), overestimations of the SM (average bias of about 4 vol.%) are mainly observed for developed tomato and soybean crops due to fruits’ emergence, whereas an extreme underestimation (average bias reaching −15.5 vol.%) is found for developed wheat cover due to the vertical structure of the wheat kernels. The results also suggest that the optimal SM estimations by S1 could be mainly obtained at low radar incidence angles (incidence angle less than 35°)
Let earthworms be functional - Definition of new functional groups based on their bioturbation behavior
No full textInternational audienceThe three main ecological categories of earthworms (anecic, endogeic, epigeic) are often used as proxies for functional groups. This is troublesome since they were not designed for this purpose and thus the relevance of such a use was never tested nor proven. How earthworms influence the different soil functions is tightly linked to their bioturbating behavior and thus they are considered as physical ecosystem engineers. Here, we characterized the different facets of this behavior (burrow creation, production of casts below and above ground, and litter consumption) for 50 species or subspecies of European earthworms under standardized laboratory conditions. Using PCA and K-means methods, we defined six new functional groups of earthworms, i.e. intense tunnelers, burrowers, shallow bioturbators, deep bioturbators, litter dwellers and intermediates. Intense tunnelers and burrowers build continuous and vertically oriented burrows, the first however burrow more and consume less litter. Deep bioturbators live deeply in the soil, make very discontinuous burrows and consume no litter. They could be seen as a novel group but they can be linked to the hypo-endogeics ecological categories defined 50 years ago. Litter-dwellers and shallow bioturbators can be respectively linked to the epidegeics and endogeics ecological categories. However, the new groups only partially overlap with the traditional ecological categories. We assume that their use, based on quantitative behavioral assessments, will improve the study of the relationships between earthworm communities and the associated provision of ecosystem services by minimizing the overlooked variability within the three main ecological categories regarding their behavior
GeoNLPlify: A spatial data augmentation enhancing text classification for crisis monitoring
No full textInternational audienceCrises such as natural disasters and public health emergencies generate vast amounts of text data, making it challenging to classify the information into relevant categories. Acquiring expert-labeled data for such scenarios can be difficult, leading to limited training datasets for text classification by fine-tuning BERT-like models. Unfortunately, traditional data augmentation techniques only slightly improve F1-scores. How can data augmentation be used to obtain better results in this applied domain? In this paper, using neural network explicability methods, we aim to highlight that fine-tuned BERT-like models on crisis corpora give too much importance to spatial information to make their predictions. This overfitting of spatial information limits their ability to generalize especially when the event which occurs in a place has evolved and changed since the training dataset has been built. To reduce this bias, we propose GeoNLPlify,1 a novel data augmentation technique that leverages spatial information to generate new labeled data for text classification related to crises. Our approach aims to address overfitting without necessitating modifications to the underlying model architecture, distinguishing it from other prevalent methods employed to combat overfitting. Our results show that GeoNLPlify significantly improves F1-scores, demonstrating the potential of the spatial information for data augmentation for crisis-related text classification tasks. In order to evaluate the contribution of our method, GeoNLPlify is applied to three public datasets (PADI-web, CrisisNLP and SST2) and compared with classical natural language processing data augmentations
Quantitative trait loci and candidate genes for physico‐chemical traits related to tuber quality in greater yam (Dioscorea alata L.)
No full textInternational audienceBACKGROUND: Starch, dry matter content (DMC), proteins, and sugars are among the major influences on yam tuber quality. Genetic improvement programs need simple, rapid, and low‐cost tools to screen large populations. The objectives of this work were, using a quantitative trait loci mapping approach (QTL) on two diploid full‐sib segregating populations, (i) to acquire knowledge about the genetic control of these traits; (ii) to identify markers linked to the genomic regions controlling each trait, which are useful for marker‐assisted selection (MAS); (iii) to validate the QTLs on a diversity panel; and (iv) to identify candidate genes from the validated QTLs. RESULTS: Heritability for all traits was moderately high to high. Significant correlations were observed between traits. A total of 25 QTLs were identified, including six for DMC, six for sugars, six for proteins, and seven for starch. The phenotypic variance explained by individual QTLs ranged from 14.3% to 28.6%. The majority of QTLs were validated on a diversity panel, showing that they are not specific to the genetic background of the progenitors. The approximate physical location of validated QTLs allowed the identification of candidate genes for all studied traits. Those detected for starch content were mainly enzymes involved in starch and sucrose metabolism, whereas those detected for sugars were mainly involved in respiration and glycolysis.CONCLUSION: The validated QTLs will be useful for breeding programs using MAS to improve the quality of yam tubers. The putative genes should be useful in providing a better understanding of the physiological and molecular basis of these important tuber quality traits
Associations between screen viewing at 2 and 3.5 years and drawing ability at 3.5 years among children from the French nationwide Elfe birth cohort
No full textInternational audienceThe effect of screen viewing on children’s cognitive development has been of concern among parents and researchers. This study investigated the association between children screen time, as reported by parents, and drawing ability, and the confounding effects of socioeconomic characteristics (such as parental education, household income, migration status) and children’s competing activities (such as drawing practice, extracurricular activity, outdoor time, sleep time, time playing with parents). Participants included 7577 children aged 3.5 years (50% girls) who underwent the Draw-a-person test (McCarthy score [range = 0–12 points]) in the French nationwide Elfe birth cohort, initiated in 2011. Sex-stratified zero-inflated Poisson regression models were used. Increased screen time was associated with a higher likelihood to obtain a null score in boys (OR 1.15, 95% CI 1.07–1.23) and girls (1.13 [1.03–1.24]) and a lower score in girls only (β = − 0.02, 95% CI − 0.04; − 0.01). After adjusting for SES, associations were no longer observed, indicating that the association between screen time and drawing abilities was confounded by socioeconomic characteristics
Analyse de la vulnérabilité du système coopératif viticole aux aléas climatiques : étude du cas d’une coopérative languedocienne touchée par un épisode de gel et une inondation lors de la campagne 2021
No full textThe expected changes in the frequency, intensity and even seasonality of climatic hazards pose a short-term threat to the viability of farming systems that are already experiencing difficulties as a result of climate change and economic disruption. To date, the interactions between climate risks and the implications of contextual changes forthe adaptation of cooperative systems to climate change have not been addressed. The aim of this dissertation is therefore to gain a deeper understanding of the vulnerability of cooperative winegrowing systems by analysing feedback from a Languedoc cooperative affected by flooding and frost in 2021. The originality of this work lies in its cross-disciplinary nature, demonstrating the value of a multi-year approach to understanding and assessing the physical, organisational and economic damage and repercussions of climatic hazards on wine-growing cooperative socio-ecosystems.Les modifications attendues de la fréquence, de l’intensité voire de la saisonnalité des aléas climatiques font peser une menace à court terme sur la viabilité des systèmes agricoles déjà mis en difficultés dans un contexte de changement climatique et de perturbations économiques. À ce jour, les interactions entre les risques climatiques tout comme les implications des évolutions contextuelles dans l’adaptation des systèmes coopératifs au changement climatique ne sont pas traitées. L’objectif de ce mémoire est donc d’approfondir la connaissance de la vulnérabilité des systèmes coopératifs viticoles grâce à l’analyse d’un retour d’expérience réalisé auprès d’une coopérative languedocienne touchée en 2021 par une inondation et un épisode de gel. L’originalité de ce travail est d’être transdisciplinaire et de montrer l’intérêt d’une approche pluriannuelle pour la compréhension et l’évaluation des dommages et répercussions physiques, organisationnelles et économiques des aléas climatiques sur les socio-écosystèmes coopératifs viticoles
Enigmatic rodents from Lavergne, a late middle Eocene (MP 16) fissure-filling of the Quercy Phosphorites (Southwest France)
No full textInternational audienceTwo somewhat “odd” taxa of theridomyid rodents, one formerly known (Bernardia marandati Vianey-Liaud, 1991) and the other new (Idicia vidalenci gen. et sp. nov.) are discussed from a taxonomical and taphonomical perspectives. These two rodents were found at Lavergne, a late middle Eocene (MP16) “phosphatière” from the Quercy (Southwest France). The genus Bernardia, being preoccupied by a scale insect (Bernardia Ashmead, 1881), is here renamed Burgia. We benefit from this nomenclatural change to describe additional new dental specimens of this patriotheridomyine species, including a previously undescribed locus (P4). The other theridomyid from Lavergne, Idicia vidalenci gen. et sp. nov., so far documented by a mandible preserving two teeth (m2-m3) is a new taxon of peculiar occlusal morphology, and whose subfamilial affinities remain unknown. These two peculiar theridomyids recorded at Lavergne are found nowhere else, whether in coeval localities in Quercy or elsewhere in Western Europe. We discuss the possible causes of their unique presence at Lavergne
Une analyse multicritères à long terme de l'interculture de la canne à sucre par rapport aux systèmes de culture conventionnels
No full textMulti-criteria approaches are needed to integrate the agronomic, environmental, and socio-economic performances of intercropping agroecosystems and asses their sustainability. Nonetheless, the temporal dynamics of intercropping agrosystems still need to be better understood, particularly in tropical systems. This study provides the first long-term multi-criteria analysis of sugarcane intercropping systems to assess how temporal changes will determine the sustainability of this practice. In an experimental trial in La Reunion, we compared six sugarcane x companion crop intercropping systems to a conventional and a low weed control cropping system over seven years. In intercropping systems, weed cover increased over time, along with species richness and manual weeding. In the conventional system, herbicide application increased over time, reducing weed pressure. Regarding biodiversity, the intercropping system only modified the weed community in the first three years, compared with the conventional or low-weed control system, before the communities homogenized under sugarcane pressure and climate. Over seven years, the intercropping system reduced herbicide application by 51% and increased soil cover by 144%, with no significant impact on yield or sucrose content. Nevertheless, this practice led to an increase of 85% in costs and 162% in working hours, mainly due to companion crop sowing. Finally, we observed no difference in soil chemical and biological fertility between cropping systems. However, the physical fertility increased with the development of companion crops and weeds in the inter-row after seven years. This study illustrates the need to consider the dynamics of intercropping systems performances over the long term. It highlights the limits of this system for weed control in sugarcane, notably through an increase in weed pressure over time, but also ways of improving it regarding costs (particularly sowing). Finally, cropping systems with spontaneous flora in the inter-row should be studied further to reduce herbicides with a limited impact on production