Lutte contre le mildiou (Pseudoperonospora cubensis) en culture de concombre biologique : compte-rendu d'essai 2005

Le mildiou des cucurbitacées (Pseudoperonospora cubensis) est la maladie aérienne la plus grave sur concombre en Agriculture Biologique. L’attaque est souvent foudroyante : concombre et mildiou appréciant tous deux des atmosphères chaudes et humides, il est difficile de jouer sur l’aération des tunnels pour limiter le développement de la maladie. De plus, les moyens de lutte disponibles en AB sont très limités (pas de variétés résistantes, produits fongicides encore peu efficaces et pas encore d'homologation contre le mildiou). L’objectif de cet essai est de : - tester l'efficacité du soufre mouillable (homologué contre oïdium) : appliqué contre les acariens dans un essai GRAB en 2004, il a montré une efficacité secondaire intéressante contre mildiou - trouver de nouvelles pistes de produits utilisables en bio : SDN extraits de plantes (extraits d'algues, tisane de saule) produits montrant une efficacité contre le mildiou sur d'autres cultures : Mycosin, Megagree

L’offre-finale baseball : un mécanisme arbitral particulier et utile

Cette étude aborde le sujet de l’arbitrage de l’offre-finale. L’étude vise tout d’abord à présenter la particularité de ce mécanisme arbitral au travers du prisme de l’arbitrage salarial pratiqué au baseball. Elle vise ensuite à promouvoir l’utilité de ce processus au sein de ce cadre sportif en proposant son emploi pour régler les litiges relatifs à la détermination du montant des indemnités de transferts des footballeurs professionnels européens.The following is a case-study about final-offer arbitration. The first objective is to describe the uniqueness of this mechanism in the context of baseball salary-arbitration. The second is to promote the utility of this process, in the context of baseball salary-arbitration. For instance, it advocates for its use to determine appropriate fees to be paid for professional european soccer players transfers

Impact of friction dampers and ductility factor on the seismic response of concrete moment resisting frame buildings

Infrastructures around the world are impacted by seismic events and therefore can suffer different types of losses that include: life, structure, economy and much more. It is important to control the vibration in structures using appropriate design methods, materials, and energy dissipation devices. There are many different types of energy dissipating devices providing supplemental damping to structures and control their vibration response. This research focuses on friction devices, particularly, the inline friction dampers used in diagonal bracings to control the vibration in buildings. There is no standard design process available in the National Building Code of Canada to design buildings with friction dampers. The procedure suggested in FEMA guidelines is quite complicated to use. The focus here is to use a rational method for building design with friction dampers and demonstrate the impact of friction dampers in the design process, and seismic response. Currently, dampers are used as a device which are supplementary to the structure post- design, to increase its strength and stiffness that benefit structures. However, that produces a highly conservative design which may not be economically justified. By letting the dampers take about a tart of the lateral forces, structure can be optimized. The effect of fiction dampers was observed by the reduction of moment and shear on columns, the reduction of cost. Six structures were designed for this study: elastic with and without dampers, moderately-ductile with and without dampers and ductile with and without dampers. This study demonstrates that by designing and applying friction dampers into the design stage, the beams and columns attract less moment and shear impacting their sizes. While designing the structure, adding dampers helped reduce the cost in material for all three structures by around 7.5% in contrasts to the same model without dampers. An optimization of the structure section was made after adding the dampers into the structure. The impact of moment and shear into the columns and beams was shown to also be reduced of nearly 25-40% (the average is 29.5%). The seismic response of the different building models was determined using nonlinear pushover and time-history analyses. The results show that despite having smaller sections for beams and columns, the structures with dampers have reduced drift as compared to those without dampers. It was clearly demonstrated that friction dampers have an impact into the design of structures making them stronger with a higher response and lower cost. After calculating the cost of material and the overall results of analysis, the ductile structure is found to be the most economical choice. However, considering the post-earthquake damage and repair cost, the moderately-ductile structure with dampers will be a better option

Multi-surface description of temperature and strain rate-dependent damage initiation and growth in ductile viscoplastic materials

A phenomenological modelling approach has been developed, based on some salient physical effects regarding void growth vs. plastic straining, to describe the transition behaviour between dense metal plasticity and micro-porous metal plasticity. Considering that void germination requires a certain amount of plastic deformation, a ‘primary’ hole nucleation criterion has been proposed, as well as a statistical law governing the ‘secondary’ hole kinetics. In a consistent way, the hole nucleation criterion accounts for the accelerating effects of stress triaxiality and, conversely, the delaying effects of temperature and strain rate. In this work, a modification of the GTN model has also been proposed, overcoming its inability to predict damage growth and fracture for zero and low triaxiality, shear-dominated deformations. In this respect the kinematic mean stress related shift mechanism has been introduced and quantified in the expression of the GTN plastic potential, enabling thus the damage growth under shear and under small negative triaxialities. The 3D constitutive equations have been implemented as user material in the engineering finite element computation code Abaqus®. Numerical simulations have been conducted considering a single finite element under simple shear on one hand and a notched cylindrical sample under remote uniaxial tensile loading on the other hand. The numerical results show clearly the influence of the hole nucleation criterion related constants on the damage and further failure of the material

Designing fit-for-purpose indicators to connect nature and people’s well-being in New Zealand

Recognizing the value of nature for people’s wellbeing is key to ensuring protection of the environment for current and future generations. However, data to demonstrate the connection between nature and wellbeing, are needed for environmental reporting, to inform policy development and evaluate progress toward outcomes. While many indicators exist, they are mostly derived from available data collected for other purposes and there is limited, if any, description of how these indicators were designed. Based on a conceptualization of nature–well-being connections, we propose a participatory process to identify fit-for-purpose indicators linking nature to human wellbeing. The process uses a series of targeted questions to explore how different aspects of wellbeing rely on nature, enabling more fitting indicators to be identified by the participatory group. The process was refined and tested in workshops with stakeholders in a New Zealand context

Technological breakthrough and innovation in the production of whey powders, with 30-40% reduction in energy costs

There are two essential stages in the elimination of water for the production of whey and permeate powders: concentration by vacuum evaporation followed by spray drying. These two operations alone represent 25% of the energy consumed by the French dairy industry, the major part of which is due to the drying stage. Indeed, 96.7% of the whey water is removed during the vacuum evaporation/concentration stage, whereas drying, which removes only 3.3% of the water, requires 31% of the total energy used over the entire process. One possible way to reduce energy consumption would be for the product to enter the drying tower at a higher level of dryness. We therefore propose replacing the drying tower with rotating evaporators, i.e. equipment adapted to highly viscous products able to pass from a liquid state to a granular state by a continuous process. Please click Additional Files below to see the full abstract

Decomposing God Classes at Siemens

International audienceA group of developers at Siemens Digital Industry Division approached our team to help them restructure a large legacy system. Several problems were identified, including the presence of God classes (big classes with thousands of lines of code and hundred of methods). They had tried different approaches considering the dependencies between the classes, but none were satisfactory. Through interaction during the last three years with a lead software architect of the project, we designed a software visualization tool and an accompanying process that allows her to propose a decomposition of a God Class in a matter of one or two hours even without prior knowledge of the class (although actually implementing the decomposition in the source code could take a week of work). In this paper, we present the process that was formalized to decompose God Classes and the tool that was designed. We give details on the system itself and some of the classes that were decomposed. The presented process and visualisations have been successfully used for the last three years on a real industrial system at Siemens