https://www.researchgate.net/publication/329529188_Comparative_Performance_Prediction_of_Historical_Thames_A_Rater_Class_Designs

The Thames A-Rater fleet is a unique class both in appearance and in its combination of historic and modern technologies. With high aspect ratio, carbon fibre rigs fitted onto wooden hulls, many of which have survived two World Wars, the class is a demonstration of the evolution of sailing technology. In more recent decades, various attempts have been made to expand the class with new composite boats. However, due to the strict rules issued by the class association, new hulls must be exact replicas of existing A-Raters, with a 1.5 inch tolerance. Furthermore, as only one linesplan exists in the public domain, the expansion of the fleet is extremely limited. Consequently, in order to ensure the conservation of some of these historic designs, the lines of several vessels were taken off and used to create accurate linesplan and 3D models. The comparative performance of the various crafts was then assessed through a Velocity Prediction Programme, focused on the specific environmental conditions of the vessels' main operating area, eventually ascertaining the hull with the best racing potential by design

On some Riemannian aspects of two and three-body controlled problems

The flow of the Kepler problem (motion of two mutually attracting bodies) is known to be geodesic after the work of Moser [20], extended by Belbruno and Osipov [2, 21]: Trajectories are reparameterizations of minimum length curves for some Riemannian metric. This is not true anymore in the case of the three-body problem, and there are topological obstructions as observed by McCord et al. [19]. The controlled formulations of these two problems are considered so as to model the motion of a spacecraft within the influence of one or two planets. The averaged flow of the (energy minimum) controlled Kepler problem with two controls is shown to remain geodesic. The same holds true in the case of only one control provided one allows singularities in the metric. Some numerical insight into the control of the circular restricted three-body problem is also be given

Abregé de la vie, vertus & miracles de Saint Jean de la Croix, premier carme dechausse et coadjunteur de Sainte Therese dans la reforme de l'ordre de Notre Dame du Mont Carmel

Copia digital. Valladolid : Junta de Castilla y León. Consejería de Cultura y Turismo, 2012-2013Sign. : a6, A-S

Exponential Tracking Control Using Backstepping Approach for Voltage-Based Control of a Flexible Joint Electrically Driven Robot

This paper addresses the design of exponential tracking control using backstepping approach for voltage-based control of a flexible joint electrically driven robot (EFJR), to cope with the difficulty introduced by the cascade structure in EFJR dynamic model, to deal with flexibility in joints, and to ensure fast tracking performance. Backstepping approach is used to ensure global asymptotic stability and its common algorithm is modified such that the link position and velocity errors converge to zero exponentially fast. In contrast with the other backstepping controller for electrically driven flexible joint robot manipulators control problem, the proposed controller is robust with respect to stiffness uncertainty and allows tracking fast motions. Simulation results are presented for both single link flexible joint electrically driven manipulator and 2-DOF flexible joint electrically driven robot manipulator. These simulations show very satisfactory tracking performances and the superiority of the proposed controller to those performed in the literature using simple backstepping methodology

Safe Childbirth and Motherhood in African Great Lakes Region: External Pelvimetry in Nulliparae and Scheduled Caesarean Section

The authors have carried out a literature review of targeted relevant research with a focus on two countries of the African Great Lakes Region, i.e. Rwanda and the Democratic Republic of the Congo (DRC). The aim was to find a common thread between nulliparity and timely caesarean section through external clinical pelvimetry. Higher rates of nulliparity and caesarean section were found with poor outcome in terms of foeto-maternal prognosis. External clinical pelvimetry presented in Rwandan and Congolese nulliparae the same characteristics during pregnancy and at delivery: lower average values in comparison with multiparae who never experienced caesarean section; average values significantly lower in women who underwent caesarean than in those who delivered naturally; and a gradual and significant decrease in caesarean section rate as pelvic sizes increased. Cephalopelvic disproportion, the main cause of mechanical dystocia, was associated with significantly lower pelvic average values. On the basis of an appropriate tool to predict cephalopelvic disproportion and taking as an illustration of complication the case of obstetrical fistulas, the authors finally advocate the use of the pelvimeter to screen in time pelvises at higher risk for cephalopelvic disproportion in resource-constrained environment

Genetic Analysis of Flower Bud Thrips Resistance (Megalurothrips sjostedti) in Cowpea (Vigna unguiculata [L.] Walp.) in Burkina Faso

Cowpea is an important grain legume in sub Saharan Africa where its protein rich grains are consumed. However, its production is hampered by some major constraints including flower bud thrips (Megalurothrips sjostedti) that can cause 60% to total crop yield loss. Therefore, the development of resistant varieties becomes necessary. Thus, the present study was designed to determine the inheritance and elucidate the genetic control of cowpea resistance to thrips. Generation mean analysis model was exploited to assess the mode of inheritance of the resistance to flower bud thrips in cowpea using six generations (P1, P2, F1, F2, BC1P1 and BC1P2) derived from cross of Komcallé and Sanzi. Parameters such as number of flowers abortion per plant, number of pods per plant, thrips damage, number of thrips per plant and 100 seeds weight were exploited for progenies evaluation. Generation mean analysis revealed the existence of additive (a), additive x dominance (ad) and dominance x dominance (dd) effects as the mode of gene action predominantly involved into cowpea for thrips resistance control. Number of effective factors for thrips damage control varied from 3 (number of aborted flowers per plant) to 6 (weight of 100 seeds). Estimated Broad and narrow sense heritabilities for flower bud thrips resistance were low indicating large effect of the environment on the trait

Contrôle optimal géométrique (méthodes homotopiques et applications)

Le contexte de ce travail est le contrôle optimal géométrique appliqué à la mécanique céleste et au contrôle quantique. On s est tout d abord intéressé au problème de transfert orbital de satellite autour de la Terre à consommation minimale,qui amena à la réalisation du code HamPath, permettant tout d abord la résolution de problème de contrôle optimal dont la loi de commande est lisse. Il se base sur le Principe du Maximum de Pontryagin (PMP) et sur la notion de point conjugué. Ce programme combine méthode de tir, méthodes homotopiques différentielles et calcul des conditions d optimalité du deuxième ordre. Nous nous intéressons par la suite au contrôle quantique. On étudie tout d abord le contrôle d un système composé de deux types de particules de spin 1/2 ayant des temps de relaxation différents et dont la dynamique est gouvernée par les équations de Bloch. Ces deux sous-systèmes,correspondant aux deux types de particules, sont couplés par un même contrôle (un champ electromagnétique), le but étant alors d amener la magnétisation des particules du premier type à zéro tout en maximisant celle du second (dans un système de coordonnées bien choisi). Ce modèle intervient en imagerie médicale par Résonance Magnétique Nucléaire et consiste à maximiser le contraste entre deux régions d une même image. L utilisation des outils géométriques et numériques aura permis de donner une très bonne synthèse sous-optimale pour deux cas particuliers (mélange sang oxygéné/désoxygéné et liquide cérébrospinal/eau). La dernière contribution de cette thèse porte sur l étude d un système quantique à deux niveaux d énergie dontl a dynamique est régie par les équations de Lindblad. Le modèle est basé sur la minimisation d énergie du transfert. On se restreint à un cas particulier pour lequelle Hamiltonien donné par le PMP est Liouville intégrable. On décrit alors les lieux conjugués et de coupure pour ce problème riemannien avec dériveThis work is about geometric optimal control applied to celestial and quantum mechanics. We first dealt with the minimum fuel consumption problem of transfering a satellite around the Earth. This brought to the creation of the code HamPath which permits first of all to solve optimal control problem for which the command law is smooth. It is based on the Pontryagin Maximum Principle (PMP) and on the notion of conjugate point. This program combines shooting method, differential homotopic methods and tools to compute second order optimality conditions. Then we are interested in quantum control. We study first a system which consists in two different particles of spin 1/2 having two different relaxation time. Both sub-systems are driven by the same control. The problem consists in bringing to zero the magnetization of one of the two system while maximizing the magnetization of the second one. This problem comes from constrast imaging in Nuclear Magnetic Resonance and consists in maximising the contrast between two areas of the image. The use of geometrical and numerical tools has given a very precise sub-optimal synthesis for two particular cases (deoxygenated/oxygenated blood and cerebrospinal fluid/water cases). The last contribution of this thesis is about the Lindblad equations in the two-level case. The model is based upon the minimisation of the transfer energy. We restrict the study to a particular case for which the Hamiltonian given by the PMP is Liouville integrable.We describe the conjugate and cut loci for this Riemannian with drift problemDIJON-BU Doc.électronique (212319901) / SudocSudocFranceF