Product family optimization: a multiplatform algorithm based on iterative increase of the commonality

International audienceThis work addresses the problem of optimizing the design of a family of products and simultaneously maximizing the commonality between these products. By commonality, we mean the proportion of components that are shared between the products. The set of all components common to all products is called platform [2, 3]. We consider here the multiplatform problem that allows the commonality to start as soon as one component is common to two products. The multiplatform formulation encompasses every possible case of commonality and leads to a highly complex optimization problem: for NP products, of each N design variables, there are (BNP )N multiplatform configurations (BNP is the Nth P number of Bell). In this paper, we propose an algorithm to tackle this multiplatform product family optimization. Similarly to [1, 3] , we will estimate the Pareto front between an aggregation of the products engineering performance and the family commonality. The proposed method is based on a quadratic approximation of the product performance functions and has a complexity of O(N ×N2 P ×log(NP )), which is much better than the complexity of any enumeration strategy ((BNP )N)

Coupled structural and magnetic properties of ferric fluoride nanostructures: part II, a Monte-Carlo Heisenberg study

We present a numerical study of the magnetic structure of nanostructured iron fluoride, using the Monte-Carlo-Metropolis simulated annealing technique and a classical Heisenberg Hamiltonian with a superexchange angle dependence. The parameters are adjusted on experimental results, and the atomic structure and topology taken from a previous atomistic model of grain boundaries in the same system. We find perfect antiferromagnetic crystalline grains and a disordered magnetic configuration (speromagnetic like) at the grain boundary, in agreement with experimental findings. Both the lowest magnetic energy and the rate of magnetic frustration are found to be dependent on the relative disorientation of crystalline grains, i.e. on the cationic topology. By simulating hysteresis loops, we find that the magnetization rotation is not spatially uniform. We conclude on possible extensions of the model.Comment: submitted to JMM

Diversité des formes de conseil agricole en Afrique de l'Ouest et du Centre

Le conseil agricole est un service important pour renforcer les capacités des agriculteurs et les performances de leurs exploitations et organisations. La pluralité des démarches et des formes de conseil témoigne des nombreuses visions de l'agriculture portée par les acteurs des filières agricoles et des territoires

Elaboration concertée de la politique publique de conseil et de vulgarisation agricoles : Volume 2 : Rapport préparatoire au document de politique publique de vulgarisation et de conseil agricoles

Le présent document est le fruit d'une réflexion collective menée de manière itérative et suivie de bout en bout par un groupe de contact permanent. Il se distingue de ce fait de trop nombreux documents de politique élaborés à dire d'experts. Le document comprend deux grandes parties complémentaires. La première constitue la déclaration de politique proprement dite ; elle comprend les éléments clés du diagnostic qui a permis de hiérarchiser les problèmes et de formuler les objectifs destinés à les résoudre ; elle comprend également les principes de base et les orientations stratégiques de la politique publique qui fixent le cap des principales actions à mettre en oeuvre. La seconde partie constitue le volet opérationnel de la politique ; elle détaille le dispositif institutionnel de mise en oeuvre et l'architecture du Système National de Vulgarisation et de Conseil Agricoles (SNVCA) qui regroupe et coordonne l'ensemble des acteurs publics et privés impliqués dans le domaine

Système national de recherche et d'innovation en Afrique : le cas du Cameroun

La transition sociodémographique des pays du sud structure les marchés intérieurs et crée des opportunités de croissance économique. En mobilisant le concept de Système National de Recherche et d'Innovation, nous testons en quoi il améliore la connaissance des conditions institutionnelles qui mobilisent les résultats de la recherche dans les processus d'innovation. Une première partie discute de l'adaptation de la notion de Système National d'Innovation aux pays du Sud. Une seconde partie caractérise les conditions historiques d'émergence des institutions de recherche au Cameroun. Une troisième partie analyse en quoi la structure de la production scientifique depuis 1991 répond aux besoins d'innovations du secteur agricole et alimentaire. La quatrième partie explicite les conditions d'utilisation de cette production par les sous-systèmes de l'intermédiation et de l'entrepreneuriat. Les résultats interrogent comment l'usage de la notion de SNRI peut devenir un élément d'orientation des politiques de recherche et d'innovation finalisées par le développement. (Résumé d'auteur

A genome‐wide association meta‐analysis of all‐cause and vascular dementia

Introduction : Dementia is a multifactorial disease with Alzheimer’s disease (AD)and vascular dementia (VaD) pathologies making the largest contributions. Yet, mostgenome-wide association studies (GWAS) focus on AD. Methods : We conducted a GWAS of all-cause dementia (ACD) and examined thegenetic overlap with VaD. Our dataset includes 800,597 individuals, with 46,902 and8702 cases of ACD and VaD, respectively. Known AD loci for ACD and VaD were repli-cated. Bioinformatic analyses prioritized genes that are likely functionally relevant andshared with closely related traits and risk factors. Results : For ACD, novel loci identified were associated with energy transport(SEMA4D), neuronal excitability (ANO3), amyloid deposition in the brain (RBFOX1), andmagnetic resonance imaging markers of small vessel disease (SVD; HBEGF). Novel VaDloci were associated with hypertension, diabetes, and neuron maintenance (SPRY2,FOXA2, AJAP1, and PSMA3). Discussion: Our study identified genetic risks underlying ACD, demonstratingoverlap with neurodegenerative processes, vascular risk factors, and cerebral SVD

PROSPECTS AND CONSTRAINTS TO THE ADOPTION OF PRECISION AGRICULTURE IN THE PRACTICE OF MARKET GARDENING IN SANTA, NORTHWEST REGION, CAMEROON

Precision Agriculture, or digital farming, is a farm management approach that uses a collection of data-driven technologies to enhance agricultural productivity and sustainability. In the context of market gardening in Santa Sub-Division in the North West Region of Cameroon, these technologies present great prospects such as increased efficiency, improved crop yields and quality, reduced cost inputs, environmental sustainability, adaptation to climate change, better decision making, market access, and increased profitability among others. Despite these great prospects, the adoption rate of these technologies by market gardeners is still very timid. Its effective adoption and implementation by farmers is being hindered by factors like; high initial cost, limited capital, lack of access to credit and funding, lack of technical expertise, data security concerns. Limited infrastructure, ignorance of its economic and environmental benefits, lack of digital skills and literacy, limited access to technologies, poor market organization, unstable land tenure practices and the lack of government support. Thus, addressing these fundamental constraints is pivotal for the successful adoption and implementation of these technologies in the practice of market gardening in the Santa Sub-division