ROLE OF CUTANEOUS AFFERENTS IN THE CONTROL OF FINE MOVEMENTS

An increase in the quantity of afferents has been observed to be less useful to normal individual, therefore to patients suffering from neurological problems. To determine the effect of reduction of cutaneous afferents in the control of fine movements.Sixty healthy individuals, age between 20 and 25 years, were randomized into 2 groups.Main outcome measures: The speed of movements was measured with a specific device constructed specially to this study, related to digital chronometer that detects 1/100 of the second. T-test was performed for outcome measure and to evaluate individual difference within groups in the presence of significance. The position at the edge of the support show an increase in the speed of the fine movement by 82% than the position completely on the support

ROLE OF CUTANEOUS AFFERENTS IN THE CONTROL OF FINE MOVEMENTS

An increase in the quantity of afferents has been observed to be less useful to normal individual, therefore to patients suffering from neurological problems. To determine the effect of reduction of cutaneous afferents in the control of fine movements.Sixty healthy individuals, age between 20 and 25 years, were randomized into 2 groups.Main outcome measures: The speed of movements was measured with a specific device constructed specially to this study, related to digital chronometer that detects 1/100 of the second. T-test was performed for outcome measure and to evaluate individual difference within groups in the presence of significance. The position at the edge of the support show an increase in the speed of the fine movement by 82% than the position completely on the support

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Cοntributiοn à l'étude des engrenages électrοmagnétiques pοur les applicatiοns énergies renοuvelables

Energy conversion systems for renewable energy rely on mechanical gearboxes to transmit mechanical power to the electrical machine at higher speeds and to avoid having very large generators. The main issue with mechanical gears is their low reliability and requirement for regular lubrication and maintenance. Magnetic gears perform power transmission between two ports through the frictionless interaction of magnetic forces. Some potential advantages of using magnetic gears are reduced maintenance, possible isolation between input and output shafts, and inherent overload protection. To cover all the objectives defined, the work was divided into four chapters. The literature overview of the first chapter has shown that remarkably high-performance magnetic gears were developed. In the second chapter, 3D and quasi-3D computationally efficient magnetic equivalent circuit models that could consider the magnetic saturation and the end-effects were presented. It was found that these methods could achieve an important time gain against the finite element method, albeit with a slight reduction in the accuracy. The third chapter included an overview of the marine renewable energy systems and the magnetic gear applications in this field, and then an optimization study was done to propose a magnetic gear design that could be suitable for marine renewable energy applications. The fourth chapter presented a study and analysis on the eccentricity defect that could occur in tubular linear machines and magnetic gears, where a 3D finite element method model was used in the analysis first, and then to reduce the computation time a quasi-3D finite element method tool was developed.Les systèmes de conversion d'énergie pour les énergies renouvelables reposent sur des boîtes de vitesses mécaniques pour transmettre la puissance mécanique à la machine électrique à des vitesses plus élevées et pour éviter d'avoir de très gros générateurs. Le principal problème des engrenages mécaniques est leur faible fiabilité et la nécessité d'une lubrification et d'un entretien réguliers. Les engrenages magnétiques assurent la transmission de puissance entre deux ports grâce à l'interaction sans frottement des forces magnétiques. Certains avantages potentiels de l'utilisation d'engrenages magnétiques sont une maintenance réduite, une isolation possible entre les arbres d'entrée et de sortie et une protection inhérente contre les surcharges. Afin de couvrir l'ensemble des objectifs définis, le travail a été divisé en quatre chapitres. L'aperçu de la littérature du premier chapitre a montré que des engrenages magnétiques remarquablement performants ont été développés. Dans le deuxième chapitre, des modèles de circuits équivalents magnétiques efficaces en calcul 3D et quasi-3D qui pourraient prendre en compte la saturation magnétique et les effets de bord ont été présentés. Il a été constaté que ces méthodes pouvaient réaliser un gain de temps important par rapport à la méthode des éléments finis, mais avec une légère réduction de la précision. Le troisième chapitre comprenait un aperçu des systèmes d'énergie marine renouvelable et des applications des engrenages magnétiques dans ce domaine, puis une étude d'optimisation a été réalisée pour proposer une conception d'engrenage magnétique qui pourrait convenir aux applications des énergies marines renouvelables. Le quatrième chapitre a présenté une étude et une analyse sur le défaut d'excentricité qui pourrait se produire dans les machines linéaires tubulaires, où un modèle de méthode d'éléments finis 3D a d'abord été utilisé, puis pour réduire le temps de calcul un élément fini quasi-3D outil méthodologique a été développé

Cοntributiοn à l'étude des engrenages électrοmagnétiques pοur les applicatiοns énergies renοuvelables

Energy conversion systems for renewable energy rely on mechanical gearboxes to transmit mechanical power to the electrical machine at higher speeds and to avoid having very large generators. The main issue with mechanical gears is their low reliability and requirement for regular lubrication and maintenance. Magnetic gears perform power transmission between two ports through the frictionless interaction of magnetic forces. Some potential advantages of using magnetic gears are reduced maintenance, possible isolation between input and output shafts, and inherent overload protection. To cover all the objectives defined, the work was divided into four chapters. The literature overview of the first chapter has shown that remarkably high-performance magnetic gears were developed. In the second chapter, 3D and quasi-3D computationally efficient magnetic equivalent circuit models that could consider the magnetic saturation and the end-effects were presented. It was found that these methods could achieve an important time gain against the finite element method, albeit with a slight reduction in the accuracy. The third chapter included an overview of the marine renewable energy systems and the magnetic gear applications in this field, and then an optimization study was done to propose a magnetic gear design that could be suitable for marine renewable energy applications. The fourth chapter presented a study and analysis on the eccentricity defect that could occur in tubular linear machines and magnetic gears, where a 3D finite element method model was used in the analysis first, and then to reduce the computation time a quasi-3D finite element method tool was developed.Les systèmes de conversion d'énergie pour les énergies renouvelables reposent sur des boîtes de vitesses mécaniques pour transmettre la puissance mécanique à la machine électrique à des vitesses plus élevées et pour éviter d'avoir de très gros générateurs. Le principal problème des engrenages mécaniques est leur faible fiabilité et la nécessité d'une lubrification et d'un entretien réguliers. Les engrenages magnétiques assurent la transmission de puissance entre deux ports grâce à l'interaction sans frottement des forces magnétiques. Certains avantages potentiels de l'utilisation d'engrenages magnétiques sont une maintenance réduite, une isolation possible entre les arbres d'entrée et de sortie et une protection inhérente contre les surcharges. Afin de couvrir l'ensemble des objectifs définis, le travail a été divisé en quatre chapitres. L'aperçu de la littérature du premier chapitre a montré que des engrenages magnétiques remarquablement performants ont été développés. Dans le deuxième chapitre, des modèles de circuits équivalents magnétiques efficaces en calcul 3D et quasi-3D qui pourraient prendre en compte la saturation magnétique et les effets de bord ont été présentés. Il a été constaté que ces méthodes pouvaient réaliser un gain de temps important par rapport à la méthode des éléments finis, mais avec une légère réduction de la précision. Le troisième chapitre comprenait un aperçu des systèmes d'énergie marine renouvelable et des applications des engrenages magnétiques dans ce domaine, puis une étude d'optimisation a été réalisée pour proposer une conception d'engrenage magnétique qui pourrait convenir aux applications des énergies marines renouvelables. Le quatrième chapitre a présenté une étude et une analyse sur le défaut d'excentricité qui pourrait se produire dans les machines linéaires tubulaires, où un modèle de méthode d'éléments finis 3D a d'abord été utilisé, puis pour réduire le temps de calcul un élément fini quasi-3D outil méthodologique a été développé

Contribution to the study of electromagnetic gears for renewable energy applications

Les systèmes de conversion d'énergie pour les énergies renouvelables reposent sur des boîtes de vitesses mécaniques pour transmettre la puissance mécanique à la machine électrique à des vitesses plus élevées et pour éviter d'avoir de très gros générateurs. Le principal problème des engrenages mécaniques est leur faible fiabilité et la nécessité d'une lubrification et d'un entretien réguliers. Les engrenages magnétiques assurent la transmission de puissance entre deux ports grâce à l'interaction sans frottement des forces magnétiques. Certains avantages potentiels de l'utilisation d'engrenages magnétiques sont une maintenance réduite, une isolation possible entre les arbres d'entrée et de sortie et une protection inhérente contre les surcharges. Afin de couvrir l'ensemble des objectifs définis, le travail a été divisé en quatre chapitres. L'aperçu de la littérature du premier chapitre a montré que des engrenages magnétiques remarquablement performants ont été développés. Dans le deuxième chapitre, des modèles de circuits équivalents magnétiques efficaces en calcul 3D et quasi-3D qui pourraient prendre en compte la saturation magnétique et les effets de bord ont été présentés. Il a été constaté que ces méthodes pouvaient réaliser un gain de temps important par rapport à la méthode des éléments finis, mais avec une légère réduction de la précision. Le troisième chapitre comprenait un aperçu des systèmes d'énergie marine renouvelable et des applications des engrenages magnétiques dans ce domaine, puis une étude d'optimisation a été réalisée pour proposer une conception d'engrenage magnétique qui pourrait convenir aux applications des énergies marines renouvelables. Le quatrième chapitre a présenté une étude et une analyse sur le défaut d'excentricité qui pourrait se produire dans les machines linéaires tubulaires, où un modèle de méthode d'éléments finis 3D a d'abord été utilisé, puis pour réduire le temps de calcul un élément fini quasi-3D outil méthodologique a été développé.Energy conversion systems for renewable energy rely on mechanical gearboxes to transmit mechanical power to the electrical machine at higher speeds and to avoid having very large generators. The main issue with mechanical gears is their low reliability and requirement for regular lubrication and maintenance. Magnetic gears perform power transmission between two ports through the frictionless interaction of magnetic forces. Some potential advantages of using magnetic gears are reduced maintenance, possible isolation between input and output shafts, and inherent overload protection. To cover all the objectives defined, the work was divided into four chapters. The literature overview of the first chapter has shown that remarkably high-performance magnetic gears were developed. In the second chapter, 3D and quasi-3D computationally efficient magnetic equivalent circuit models that could consider the magnetic saturation and the end-effects were presented. It was found that these methods could achieve an important time gain against the finite element method, albeit with a slight reduction in the accuracy. The third chapter included an overview of the marine renewable energy systems and the magnetic gear applications in this field, and then an optimization study was done to propose a magnetic gear design that could be suitable for marine renewable energy applications. The fourth chapter presented a study and analysis on the eccentricity defect that could occur in tubular linear machines and magnetic gears, where a 3D finite element method model was used in the analysis first, and then to reduce the computation time a quasi-3D finite element method tool was developed

Open Circuit Performance of Axial Air Gap Flux Switching Permanent Magnet Synchronous Machine for Wind Energy Conversion: Modeling and Experimental Study

The aim of this paper is to present the design and modeling of a machine that possesses some advantageous characteristics for wind energy conversion applications. The studied machine is a double stator inner rotor axial airgap flux switching permanent magnet machine (AFSPM). The paper will start by presenting this type of machine and its points of interest. Then, it will continue by introducing the constructed prototype and its specifications and structure. This prototype has been designed based on a reference specification used at GREAH to develop different prototypes and compare their performances. The second part will introduce the reluctance network model specifically constructed for this type of machine. The constructed model was validated by comparing its results to the results from the finite element method model. Finally, the experimental results will be presented and compared to the reluctance network (RN) model results where satisfying agreement between both results was obtained

Design and Realization of a Hybrid Excited Flux Switching Vernier Machine for Renewable Energy Conversion

International audienceThis paper presents the design of a hybrid excited flux switching Vernier machine. This machine is designed to serve in renewable energy conversion applications, such as a wind turbine generator, or tidal turbine generator. After introducing this original structure, a design based on finite element models is conducted. The specifications correspond to relatively low power direct drive wind or tidal turbine applications. The rated power is set to 10 kW, with a rated speed of 300 rpm. Mainly the electromagnetic design is presented. Aspects related to the realization of a prototype are also presented, and an experimental study is included

Introduction to Mesh Based Generated Lumped Parameter Models for Electromagnetic Problems using Triangular Elements

This paper is an introduction to mesh based generated reluctance network modeling using triangular elements. Many contributions on mesh based generated reluctance networks using rectangular shaped elements have been published, but very few on those generated from a mesh using triangular elements. The use of triangular elements is aimed at extending the application of the approach to any shape of modeled devices. Basic concepts of the approach are presented in the case of electromagnetic devices. The procedure for coding the approach in the case of a flat linear permanent magnet machine is presented. Codes developed under MATLAB environment are also included