ParisTech

About: ParisTech is a education organization based out in Paris, France. It is known for research contribution in the topics: Residual stress & Finite element method. The organization has 1888 authors who have published 1965 publications receiving 55532 citations. The organization is also known as: Paris Institute of Technology & ParisTech Développement.

Five-Phase Version of 12Slots/8Poles Three-Phase Synchronous Machine for Marine-Propulsion

Abstract: This paper proposes a simple and effective scheme for Direct Torque Control (DTC) of Brushless DC Motor. Unlike the traditional DTC where both the torque and flux must to be employed in order to deliver the switching table for the inverter, the proposed DTC scheme utilizes only the torque information. By considering the particular operating principle of the motor, the instantaneous torque can be estimated only by using back EMF ratio in an unified differential equation. The simulation results have shown the good performance of the proposed scheme. It can be seen thus a very suitable technique for EV drives which need fast and precise torque response.

Modeling growth of organized nanoporous structures by anodic oxidation.

Abstract: Nanostructured porous oxides are produced by anodic dissolution of several metals. A scaling approach is introduced to explain pattern nucleation in an oxide layer, and a related microscopic model shows oxide growth with long nanopores. The scaling approach matches the time of ion transport across the thin oxide layer, which is related to metal corrosion, and the time of diffusion along the oxide/solution (OS) interface, which represents the extension of oxide dissolution. The selected pattern size is of order (dDS/vO)1/2, where d is the oxide thickness, vO is the migration velocity of oxygen ions across the oxide, and Ds is the diffusion coefficient of H+ ions along the oxide/solution interface. This result is consistent with available experimental data for those quantities, predicts the increase of pore size with the external voltage, and suggests the independence of pore size with the solution pH. Subsequently, we propose a microscopic model that expresses the main physicochemical processes as a set of...

The CDM framework: Knowledge recombination from an evolutionary viewpoint

Abstract: Since Crepon, Duguet, and Mairesse published their ground-breaking article (‘Research, Innovation and Productivity: An Econometric Analysis at the Firm Level’, 1998), the CDM framework has known a large diffusion, despite being published in a non-indexed journal. The present study is an exploration of the spread and recombination of ‘knowledge’ in the ‘CDM universe’, comprising all papers in Scopus indexed journals citing CDM or/and CDM cited papers. We assess first the speed and range of diffusion of CDM and investigate next the ‘origins’ and further ‘genealogical’ make up of the knowledge recombinations within the CDM universe. We find that CDM is cited by a growing number of papers, which spread over a variety of fields, and that it compares very well with the most cited comparable articles in indexed journals in its domain of research. We further find that the CDM universe is mainly constituted of three large clusters and for each of them we are able to identify knowledge paths going from the ...

Multicenter study of 37 pediatric patients with SCIWORA or other spinal cord injury without associated bone lesion.

Abstract: Background Pure traumatic spinal cord injury (without associated bone lesion) are encountered in pediatric accidentology, the most typical being spinal cord injury without radiological abnormality (SCIWORA). The present study reports a multicenter series of under-18-year-olds admitted for traumatic medullary lesion. The objectives were: (1) to describe the causes of pure spinal cord injuries in children in France and their clinical presentation; (2) to identify any prognostic factors; and (3) to describe their medical management in France. Patients and method A multicenter retrospective study was conducted in 3 pediatric spine pathology reference centers. Files of 37 patients with confirmed spinal cord injury between January 1988 and June 2017 were analyzed: SCIWORA (n = 30), myelopathy associated with severe cranial trauma (n = 2), and obstetric trauma (n = 5). Accident causes, associated lesions, initial Frankel grade, level of clinical spinal cord injury, initial MRI findings, type of treatment and neurology results at last follow-up were collated. The main endpoint was neurologic recovery, defined by improvement of at least 1 Frankel grade. Results Causes comprised 17 road accidents, 11 sports accidents, 5 obstetric lesions and 4 falls. Mean follow-up was 502 days. The rate of at least partial neurologic recovery was 20/30 in SCIWORA, 0/5 in obstetric trauma, and 0/4 in case of associated intracranial lesion. In SCIWORA, factors associated with recovery comprised age, accident type, and absence of initial MRI lesion. Discussion We report a large series of pediatric spinal cord injury without associated bone lesion. This is a potentially serious pathology, in which prognosis is mainly related to age and trauma mechanism. Level of evidence IV, case series.