Search results for "Multi"

Can we improve the birth weight prediction?: the effect of normal BMI using a multivariate model

2015

Objective: The construction of a predictive model that improves the estimation of the fetal weight (EFW). Study Design: a comparative, descriptive study. One hundred forty pregnant women were recruited at two-stage sample in health department in Spain. They were classified in four groups depending on the pre-gestational BMI. Fetal weight at term was estimated by ultrasound at 33-35 weeks (EFW40w) by one gynecologist. A regression model was created with the variables that reacted to the newborn's weight, symphysis-fundal height (SFH), EFW40w, gestational age (GA), ferritin level and cigarettes smoked. Results: A multivariate model was created for the NW group to estimate the fetal weight (EF…

Co-développement d'un modèle d'aide à la décision pour la gestion intégrée de la flore adventice. Méta-modélisation et analyse de sensibilité d'un mo…

2018

The main threat to agricultural crops are weeds with herbicides being the primary cropping management practice. Due to the negative impact of herbicides on health and environment, their use must be reduced. To replace herbicides, numerous cropping practices need to be implemented. This makes weed management more complicated and, together with necessity of scheduling operations at long-term and the multiplicity of cropping system impacts, explains why models are so useful for designing innovative cropping systems. The aim of this thesis was to develop a Decision Support System (DSS) intended for crop advisors to help design cropping systems that are less dependent on herbicides. Our approach…

A Multi objective inventory model for short food supply chains

2017

Over the past 50 years, vertically integrated multinationals dominated global food markets by providing huge product diversity at low prices. Such systems are characterized by long supply chains capable of achieving high cost efficiencies resulting from the use of cheap raw materials, high chemical inputs, industrial shelf-life extension processes, economies of scale and mechanization. This dominant position on the market, however, has been achieved at a heavy cost on the global environment, generated by massive food wastage, and by a steady supply of fossil fuels. For such reasons, global supply chains are considered unsustainable and new food systems are being promoted in order to replace…

Supporting Multi-Sided Platform firms to maintain rapid growth (and to avoid failure) over time through a Dynamic Business Modelling approach

2020

Over the last few decades, the diffusion of the sharing economy has nurtured continuous changes in business model opportunities with multi-sided platforms (MSPs) in many industries. MSPs are digital exchange platforms aiming at connecting unmatched demand- and supply- side participants through the use of internet technology. In many cases, such start-up initiatives have led to the creation of scale-up or high-growth firms (HGFs). However, in spite of the significant contribution to both economic development and employment, current studies seem to investigate primarily in an isolated perspective HGFs, MSPs and their business model innovation (BMI). The existing literature on HGFs focuses on …

Measurement of top-quark polarisation observables and a search for dark matter in single-top-quark production with the ATLAS detector at the LHC

2022

Esta tesis presenta dos análisis diferentes basados en los datos resultantes de colisiones protón-protón a una energía en el centro de masas de 13 TeV recolectados con el detector ATLAS del LHC, correspondientes a una luminosidad integrada de 139 fb$^{-1}$. El primer análisis presenta una medida de secciones eficaces diferenciales normalizadas del canal de producción de quarks top en solitario $t$-channel, donde el quark top se desintegra leptónicamente, como función de los tres ángulos de polarización del leptón para eventos con quarks top y quarks antitop tanto separadamente como de forma inclusiva. Estos observables son particularmente sensibles a efectos de nueva física en el vértice $t…

TES microcalorimeter for IXO: From focal plane to anticoincidence detector

2009

The high resolution spectroscopy provides a unique technique to extract fundamental information in X-ray Astrophysics and Cosmology. In order to exploit at the best the capability of carrying out spectroscopy of faint sources, great care must be taken to reduce the background in the main detector. In this paper, we will present the working principle of a TES (Transition Edge Sensor) Microcalorimeter, its application for fine spectroscopy and a novel anticoincidence technique , based itself on a TES detector. Recent results from the first sample of the IXO-anticoincidence detector will be also shown.

The household location in multicenter urban spaces

1991

In multicenter urban spaces, the household location problem is to find an optimal location taking into account the locations of several economic centers.In this article, we show that the usual model, maximizing a residential utility under a budget spatial constraint, can’t give a satisfactory solution.So, we construct a fuzzy spatial model, including imprecision in consumer’s behavior. This model allows us to find an optimal location in a multicenter urban setting. Then, an empirical study illustrates the performances of the fuzzy model.

CoSAC, un projet pour la conception de stratégies durables de gestion des adventices dans un contexte de changement (climat, pratiques agricoles, bio…

2016

The CoSAC project associates partners from research and development in order to (1) quantify and understand, with experiments, the effects of novel agricultural practices on weeds and the functioning of the agroecosystem, (2) design tools that predict the effect of agricultural techniques et pedoclimate on weed flora, (3) use these tools to design sustainable weed management strategies and to evaluate their performances in contexts of changing agricultural practices, climate, biodiversity, (4) facilitate the adoption of these novel strategies by farmers. We will present the first results of the project, e.g. the effect on weeds of cover crops during fallow or associated to a cash crop, the …

Forecasting correlated time series with exponential smoothing models

2011

Abstract This paper presents the Bayesian analysis of a general multivariate exponential smoothing model that allows us to forecast time series jointly, subject to correlated random disturbances. The general multivariate model, which can be formulated as a seemingly unrelated regression model, includes the previously studied homogeneous multivariate Holt-Winters’ model as a special case when all of the univariate series share a common structure. MCMC simulation techniques are required in order to approach the non-analytically tractable posterior distribution of the model parameters. The predictive distribution is then estimated using Monte Carlo integration. A Bayesian model selection crite…

2017

Aqueous humour (AH) is an important biologic fluid that maintains normal intraocular pressure and contains proteins that regulate the homeostasis of ocular tissues. Any alterations in the protein compositions are correlated to the pathogenesis of various ocular disorders. In recent years, gender-based medicine has emerged as an important research focus considering the prevalence of certain diseases, which are higher in a particular sex. Nevertheless, the inter-gender variations in the AH proteome are unknown. Therefore, this study endeavoured to characterize the AH proteome to assess the differences between genders. Thirty AH samples of patients who underwent cataract surgery were categoriz…