Search results for "mecA"
showing 10 items of 475 documents
Efficiency improvement of a ground coupled heat pump system from energy management
2011
The installed capacity of an air conditioning system is usually higher than the average cooling or heating demand along the year. So, most of the time, the system is working under its actual capacity. In this contribution, we study the way to improve the efficiency of a ground coupled heat pump air conditioning system by adapting its produced thermal energy to the actual thermal demand. For this purpose, an air conditioning system composed by a ground coupled heat pump and a central fan coil linked to an office located in a cooling dominated area was simulated, and a new management strategy aiming to diminish electrical consumption was developed under the basic constraint that comfort requi…
Risk assessment of component failure modes and human errors using a new FMECA approach: application in the safety analysis of HDR brachytherapy
2014
Failure mode, effects and criticality analysis (FMECA) is a safety technique extensively used in many different industrial fields to identify and prevent potential failures. In the application of traditional FMECA, the risk priority number (RPN) is determined to rank the failure modes; however, the method has been criticised for having several weaknesses. Moreover, it is unable to adequately deal with human errors or negligence. In this paper, a new versatile fuzzy rule-based assessment model is proposed to evaluate the RPN index to rank both component failure and human error. The proposed methodology is applied to potential radiological over-exposure of patients during high-dose-rate brach…
Safety study of an LNG regasification plant using an FMECA and HAZOP integrated methodology
2015
Abstract A safety analysis was performed to determine possible accidental events in the storage system used in the liquefied natural gas regasification plant using the integrated application of failure modes, effects and criticality analysis (FMECA) and hazard and operability analysis (HAZOP) methodologies. The goal of the FMECA technique is the estimation of component failure modes and their major effects, whereas HAZOP is a structured and systematic technique that provides an identification of the hazards and the operability problems using logical sequences of cause-deviation-consequence of process parameters. The proposed FMECA and HAZOP integrated analysis (FHIA) has been designed as a …
Péptidos antihipertensivos derivados de proteínas lácteas: producción mediante levaduras no convencionales y mecanismos de acción
2015
En esta Tesis Doctoral se ha estudiado el potencial de levaduras no convencionales, pertenecientes a las especies Debaryomyces hansenii, Kluyveromyces lactis y Kluyveromyces marxianus, para generar hidrolizados y péptidos antihipertensivos provenientes de caseína (CN) o lactoferrina (LF). Además, se ha profundizado en el mecanismo de acción responsable del efecto antihipertensivo. Para ello, se han utilizado diferentes aproximaciones experimentales que incluyen ensayos in vitro para determinar los efectos inhibitorios sobre la actividad de la enzima conversora de angiotensina (ECA) y ensayos in vivo en ratas espóntaneamente hipertensas (SHRs) para estudiar los efectos sobre la presión arter…
Microfabrication of hybrid fluid membrane for microengines
2015
International audience; This paper describes the microfabrication and dynamic characterization of thick membranes providing a technological solution for microengines. The studied membranes are called hybrid fluid-membrane (HFM) and consist of two thin membranes that encapsulate an incompressible fluid. This work details the microelectromechanical system (MEMS) scalable fabrication and characterization of HFMs. The membranes are composite structures based on Silicon spiral springs embedded in a polymer (RTV silicone). The anodic bonding of multiple stacks of Si/glass structures, the fluid filling and the sealing have been demonstrated. Various HFMs were successfully fabricated and their dyna…
Global Linear Stability Analysis of the Flow Around a Superhydrophobic Circular Cylinder
2016
International audience; Over the last few years, superhydrophobic (SH) surfaces have been receiving an increasing attention in many scientific areas by virtue of their ability to enhance flow slip past solid walls and reduce the skin-friction drag. In the present study, a global linear-stability analysis is employed to investigate the influence of the SH-induced slip velocity on the primary instability of the 2D flow past a circular cylinder. The flow regions playing the role of 'wavemaker' are identified by considering the structural sensitivity of the unstable mode, thus highlighting the effect of slip on the global instability of the considered flow. In addition, a sensitivity analysis t…
Mechanical characterization of bio-based composite/metal laminates for an application in street furniture
2019
In this work, it is proposed to study the influence of three manufacturing parameters in the development of bio-basedcomposite/steel hybrids. These parameters arethe methodof assembly between composite and metal, the distribution of composite and steellayers throughthe thicknessof the hybrid,and the stacking sequence of the composite part of the hybrid. The study was conducted through impact tests at different energies and quasi-static three-point bending tests. For each of these parameters, the influenceon the mechanical properties of the hybrid is evaluated.The results show that these properties depend essentially on the relative distribution of steel and composite through the thickness.
Stream‐Discharge Surges Generated by Groundwater Flow
2019
International audience
ICR in human cadaveric specimens: An essential parameter to consider in a new lumbar disc prosthesis design.
2020
[EN] Study design Biomechanical study in cadaveric specimens. Background The commercially available lumbar disc prostheses do not reproduce the intact disc's Instantaneous centre of Rotation (ICR), thus inducing an overload on adjacent anatomical structures, promoting secondary degeneration. Aim To examine biomechanical testing of cadaveric lumbar spine specimens in order to evaluate and define the ICR of intact lumbar discs. Material and Methods Twelve cold preserved fresh human cadaveric lumbosacral spine specimens were subjected to computerized tomography (CT), magnetic resonance imaging (MRI) and biomechanical testing. Kinematic studies were performed to analyse range of movements in or…
Influence du vieillissement hygrothermique sur la tenue à l'impact de stratifiés quasi-isotropes/quasi homogènes
2011
International audience; La présente étude a pour objectif de déterminer l'influence du vieillissement hygrothermique sur la tolérance à l'impact de stratifiés possédant des propriétés particulières d'isotropie. Trois stratifications de 24 plis carbone/époxy ont été étudiées. Deux d'entre elles conduisent à des propriétés d'isotropie en membrane et en flexion, la troisième est isotrope en membrane et anisotrope en flexion. Les stratifiés obtenus après cuisson suivant le cycle préconisé par le fabricant ont été découpés pour obtenir des éprouvettes carrées destinées au vieillissement et à l'impact. Le vieillissement a été réalisé grâce à une enceinte climatique à une température de 70 °C sous…