MULTI‐PHYSICAL MODELLING AND PROTOTYPING OF AN ENERGY HARVESTING SYSTEM INTEGRATED IN A RAILWAY PNEUMATIC SUSPENSION

The aim of this PhD thesis is the investigation of an energy harvesting system to be integrated in a railway pneumatic spring to recovery otherwise wasted energy source from suspension vibration. Exploiting the piezoelectric effect to convert the mechanical energy into an electrical one, the final scope consists on the use of this system to power supply one or more sensors that can give useful information for the monitoring and the diagnostics of vehicle or its subsystems. Starting from the analysis of the energy sources, a multi‐physical approach to the study of an energy harvesting system is proposed to take into account all physics involved in the phenomenon, to make the most of the otherwise wasted energy and to develop a suitable and affordable tool for the design. The project of the energy harvesting device embedded in a railway pneumatic spring has been carried out by means of using a finite element technique and multi‐physics modelling activity. The possibility to combine two energy extraction processes was investigated with the purpose of making the most of the characteristics of the system and maximize the energy recovering. Exploiting commercial piezoelectric transducers, an experimental activity was conducted in two steps. A first mock‐up was built and tested on a shaker to develop the device and to tune the numerical model against experimental evidence. In the second step a fullscale prototype of an air spring for metro application with the EH system was realized. In order to test the full‐scale component, the design of a new test bench was carried out. Finally, the Air spring integrated with the EH device was tested and models validated

Not only P-glycoprotein: amplification of the ABCB1-containing chromosome region 7q21 confers multidrug resistance upon cancer cells by coordinated overexpression of an assortment of resistance-related proteins

The development of drug resistance continues to be a dominant hindrance toward curative cancer treatment. Overexpression of a wide-spectrum of ATP-dependent efflux pumps, and in particular of ABCB1 (P-glycoprotein or MDR1) is a well-known resistance mechanism for a plethora of cancer chemotherapeutics including for example taxenes, anthracyclines, Vinca alkaloids, and epipodopyllotoxins, demonstrated by a large array of published papers, both in tumor cell lines and in a variety of tumors, including various solid tumors and hematological malignancies. Upon repeated or even single dose treatment of cultured tumor cells or tumors in vivo with anti-tumor agents such as paclitaxel and doxorubicin, increased ABCB1 copy number has been demonstrated, resulting from chromosomal amplification events at 7q11.2-21 locus, leading to marked P-glycoprotein overexpression, and multidrug resistance (MDR). Clearly however, additional mechanisms such as single nucleotide polymorphisms (SNPs) and epigenetic modifications have shown a role in the overexpression of ABCB1 and of other MDR efflux pumps. However, notwithstanding the design of 4 generations of ABCB1 inhibitors and the wealth of information on the biochemistry and substrate specificity of ABC transporters, translation of this vast knowledge from the bench to the bedside has proven to be unexpectedly difficult. Many studies show that upon repeated treatment schedules of cell cultures or tumors with taxenes and anthracyclines as well as other chemotherapeutic drugs, amplification, and/or overexpression of a series of genes genomically surrounding the ABCB1 locus, is observed. Consequently, altered levels of other proteins may contribute to the establishment of the MDR phenotype, and lead to poor clinical outcome. Thus, the genes contained in this ABCB1 amplicon including ABCB4, SRI, DBF4, TMEM243, and RUNDC3B are overexpressed in many cancers, and especially in MDR tumors, while TP53TG1 and DMTF1 are bona fide tumor suppressors. This review describes the role of these genes in cancer and especially in the acquisition of MDR, elucidates possible connections in transcriptional regulation (co-amplification/repression) of genes belonging to the same ABCB1 amplicon region, and delineates their novel emerging contributions to tumor biology and possible strategies to overcome cancer MDR

Fractional Calculus Approach to Reproduce Material Viscoelastic Behavior, including the Time–Temperature Superposition Phenomenon

The design of modern products and processes cannot prescind from the usage of viscoelastic materials that provide extreme design freedoms at relatively low cost. Correct and reliable modeling of these materials allows effective use that involves the design, maintenance, and monitoring phase and the possibility of reuse and recycling. Fractional models are becoming more and more popular in the reproduction of viscoelastic phenomena because of their capability to describe the behavior of such materials using a limited number of parameters with an acceptable accuracy over a vast range of excitation frequencies. A particularly reliable model parametrization procedure, using the poles-zeros formulation, allows researchers to considerably reduce the computational cost of the calibration process and avoid convergence issues typically occurring for rheological models. The aim of the presented work is to demonstrate that the poles-zeros identification methodology can be employed not only to identify the viscoelastic master curves but also the material parameters characterizing the time-temperature superposition phenomenon. The proposed technique, starting from the data concerning the isothermal experimental curves, makes use of the fractional derivative generalized model to reconstruct the master curves in the frequency domain and correctly identify the coefficients of the WLF function. To validate the methodology, three different viscoelastic materials have been employed, highlighting the potential of the material parameters' global identification. Furthermore, the paper points out a further possibility to employ only a limited number of the experimental curves to feed the identification methodology and predict the complete viscoelastic material behavior

Événement : Lumières d’ailleurs. Rencontres de l’édition étrangère et de la traduction, Lyon 2014

Organisées par les étudiants du Master 2 Pro TLEC de la Faculté des langues de l’université Lyon 2, ces rencontres se sont tenues les 23-24-25 janvier 2014 dans le cadre suggestif du Musée des Moulages de Lyon. La conférence inaugurale a été confiée à Jean-Yves Masson qui a examiné du point de vue historique, littéraire, éditorial et disons, syndical, les aspects inhérents à la traduction, une véritable lectio magistralis. La première journée était axée sur différentes tables rondes privilégi..

Ouvrage : La Cigarette et le Néant, Horace Engdahl

Il y a une page célèbre de La coscienza di Zeno, où Italo Svevo disserte sur son addiction à la cigarette. Le propos « Puisque fumer me fait mal, je ne fumerai plus mais avant je veux le faire pour la dernière fois », jamais observé, est devenu paradigmatique de l’ennui et de l’angoisse existentiels. Écrivain et critique, membre de l’Académie suédoise, Horace Engdahl ne cite jamais l’écrivain italien, mais en cite des dizaines d’autres, classiques et modernes, de son pays et d’Europe, dans un..

Événement : Lumières d’ailleurs. Rencontres de l’édition étrangère et de la traduction, Lyon 2014

Organisées par les étudiants du Master 2 Pro TLEC de la Faculté des langues de l’université Lyon 2, ces rencontres se sont tenues les 23-24-25 janvier 2014 dans le cadre suggestif du Musée des Moulages de Lyon. La conférence inaugurale a été confiée à Jean-Yves Masson qui a examiné du point de vue historique, littéraire, éditorial et disons, syndical, les aspects inhérents à la traduction, une véritable lectio magistralis. La première journée était axée sur différentes tables rondes privilégi..

Ouvrage : La Cigarette et le Néant, Horace Engdahl

Il y a une page célèbre de La coscienza di Zeno, où Italo Svevo disserte sur son addiction à la cigarette. Le propos « Puisque fumer me fait mal, je ne fumerai plus mais avant je veux le faire pour la dernière fois », jamais observé, est devenu paradigmatique de l’ennui et de l’angoisse existentiels. Écrivain et critique, membre de l’Académie suédoise, Horace Engdahl ne cite jamais l’écrivain italien, mais en cite des dizaines d’autres, classiques et modernes, de son pays et d’Europe, dans un..

Review on friction and wear test rigs: An overview on the state of the art in tyre tread friction evaluation

The future evolution of autonomous mobility and road transportation will require substantial improvements in tyre adherence optimization. As new technologies being deployed in tyre manufacturing reduce total vehicle energy consumption, the contribution of tyre friction for safety and performance enhancement continues to increase. For this reason, the tyre’s grip is starting to drive the focus of many tyre developments nowadays. This is because the tread compound attitude to maximize the interaction forces with the ground is the result of a mix of effects, involving polymer viscoelastic characteristics, road roughness profiles and the conditions under which each tyre works during its lifespan. In such a context, mainly concerning the automotive market, the testing, analysis and objectivation of the friction arising at the tread interface is performed by means of specific test benches called friction testers. This paper reviews the state of the art in such devices’ development and use, with a global overview of the measurement methodologies and with a classification based on the working and specimen motion principle. Most tyre friction testers allow one to manage the relative sliding speed and the contact pressure between the specimen and the counter-surface, while just some of them are able to let the user vary the testing temperature. Few devices can really take into account the road real roughness, carrying out outdoor measurements, useful because they involve actual contact phenomena, but very complex to control outside the laboratory environment