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Within the Walloon Action Programme, transposition of the Nitrates Directive, the Administration organizes each year a control of the soil nitrate nitrogen residues in about 900 parcels located in vulnerable zone in order to verify if the practices of nitrogen spreading by the farmers are in accordance with the Walloon Action Programme. The current method is to yearly spot "suspects" by a control in three parcels in about 300 farms and to follow "suspects" by an observation programme wich leads after maximum six years to a penalty or to the end of this programme. The present statistical study means to assess the public control's methodology: what is the probability to penalize a "good" farmer, to forget a "bad" farmer? This study is based on real data and on a theoretical approach. Both conclusions indicate that the official methodology is sufficiently appropriate.

Dans le cadre du Programme de Gestion Durable de l’Azote en agriculture (PGDA), transposition de la Directive Nitrates, le Service Public de Wallonie (SPW) organise chaque année, depuis 2008, un contrôle du reliquat en azote nitrique dans le sol dans près de 900 parcelles situées en zone vulnérable afin de vérifier si la gestion des engrais azotés par l’agriculteur est conforme aux obligations fixées par le PGDA. La méthodologie développée par le SPW consiste d’une part, à déceler les cas « suspects » par le contrôle en automne du reliquat azoté dans trois parcelles de quelque 300 exploitations agricoles et d’autre part, à suivre les « suspects » dans le cadre d’un programme d’observation qui conduit après un maximum de six ans à une amende ou à la fin du programme. L’article évalue l’efficacité de la méthodologie du SPW : détecte-t-on efficacement les suspects ? au terme du programme d’observation, les « mauvaises » pratiques seront-elles exclusivement sanctionnées ? L’étude est réalisée à partir des observations menées au cours de trois années dans 23 exploitations agricoles, ainsi que de manière conceptuelle, par le calcul de probabilités sur la base de l’hypothèse d’une proportion constante dans le temps de parcelles non conformes. Les résultats de l’étude indiquent que la méthodologie actuelle du contrôle public présente un rapport cout/efficacité acceptable.

This paper presents a novel approach to skill modeling acquired from human demonstration. The approach is based on fuzzy modeling and is using a planner for generating corresponding robot trajectories. One of the main challenges stems from the morphological differences between human and robot hand/arm structure, which makes direct copying of human motions impossible in the general case. Thus, the planner works in hand state space, which is defined such that it is perception-invariant and valid for both human and robot hand. We show that this representation simplifies task reconstruction and preserves the essential parts of the task as well as the coordination between reaching and grasping motion. We also show how our approach can generalize observed trajectories based on multiple demonstrations and that the robot can match a demonstrated behavoir, despite morphological differences. To validate our approach we use a general-purpose robot manipulator equipped with an anthropomorphic three-fingered robot hand., QC 20141008

Objective: To study the long-term effects of selegiline in monotherapy and in combination with levodopa in the early phase of Parkinson disease (PD). Methods: One hundred fifty-seven de novo PD patients were randomized in a double-blind, placebo-controlled study of 7 years' duration. In the monotherapy part, selegiline significantly delayed the initiation of levodopa therapy vs placebo. The authors now report the results from the combination part of the study, in which 140 patients received selegiline or placebo in addition to individually tailored levodopa therapy. Results: Compared with placebo, selegiline slowed the progression of disease disability as measured by the Unified Parkinson Disease Rating Scale (UPDRS) total score (p = 0.003) or by motor (p = 0.002) and Activities of Daily Living (p = 0.0002) subscores. After 5 years in combination therapy, the mean difference in the UPDRS total score was nearly 10 points, with patients receiving placebo having 35% higher scores. Simultaneously, patients receiving placebo needed progressively higher doses of levodopa than patients receiving selegiline, after 5 years, the mean dosage of levodopa was 19% higher with placebo than with selegiline (p = 0.0002). Considering the entire (monotherapy and combination therapy) 7-year study time, there was a trend for selegiline to delay the start of wearing-off fluctuations (hazard ratio 0.55, p = 0.08). In both phases of the study, selegiline was safe and well tolerated. Conclusions: The results of this long-term study confirm earlier findings indicating that selegiline delays the progression of the signs and symptoms of Parkinson disease. Copyright © 2006 by AAN Enterprises, Inc.

Fuzzy gain schedulers are designed on the basis of a conventional modeling of the nonlinear controlled system and the division of the state space into a finite number of fuzzy regions. Linearization of the nonlinear system at the center of each fuzzy region leads to the design of a set of linear control laws that locally stabilize the linearized system, and consequently the original nonlinear system at the corresponding operating point. Gain scheduling control of the original nonlinear system can be therefore realized along an a priori unknown, but slowly time varying desired trajectory. In this paper we analyze the stability and robustness of the gain-scheduled closed-loop system by adopting ideas from sliding mode control. It is shown that gain scheduling control of the original nonlinear system can be realized along an a priori unknown, but slowly time-varying desired trajectory. It is shown how the advantages of the sliding mode types of analysis of a fuzzy gain scheduler can also be used for its design. © 2001 Elsevier Science B.V.

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