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.

Induced innovation in energy technologies and systems: a review of evidence and potential implications for CO2 mitigation

Abstract: We conduct a systematic and interdisciplinary review of empirical literature assessing evidence on induced innovation in energy and related technologies. We explore links between demand-drivers (both market-wide and targeted); indicators of innovation (principally, patents); and outcomes (cost reduction, efficiency, and multi-sector/macro consequences). We build on existing reviews in different fields and assess over 200 papers containing original data analysis. Papers linking drivers to patents, and indicators of cumulative capacity to cost reductions (experience curves), dominate the literature. The former does not directly link patents to outcomes; the latter does not directly test for the causal impact of on cost reductions. Diverse other literatures provide additional evidence concerning the links between deployment, innovation activities, and outcomes. We derive three main conclusions. (a) Demand-pull forces enhance patenting; econometric studies find positive impacts in industry, electricity and transport sectors in all but a few specific cases. This applies to all drivers-general energy prices, carbon prices, and targeted interventions that build markets. (b) Technology costs decline with cumulative investment for almost every technology studied across all time periods, when controlled for other factors. Numerous lines of evidence point to dominant causality from at-scale deployment (prior to self-sustaining diffusion) to cost reduction in this relationship. (c) Overall innovation is cumulative, multi-faceted, and self-reinforcing in its direction (path-dependent). We conclude with brief observations on implications for modelling and policy. In interpreting these results, we suggest distinguishing the economics of active deployment, from more passive diffusion processes, and draw the following implications. There is a role for policy diversity and experimentation, with evaluation of potential gains from innovation in the broadest sense. Consequently, endogenising innovation in large-scale models is important for deriving policy-relevant conclusions. Finally, seeking to relate quantitative economic evaluation to the qualitative socio-technical transitions literatures could be a fruitful area for future research.

Introduction of variability into pantograph–catenary dynamic simulations

Abstract: In railways, electrical current is generally collected by the train through a complex coupledmechanical system composed of a pantograph and a catenary. Dynamic phenomena that occur duringtheir interaction are still not fully understood. Furthermore, the system behaviour is sensitive to numerousparameters and thus highly variable. The first contribution of this thesis is a detailed analysis of thepantograph-catenary dynamic interaction separating phenomena due to the dynamic response of the pantographto the catenary geometry from wave propagations, reflections and transmissions that occur in thecatenary. The coincidence of frequencies or characteristic times is then shown to explain most variationsin the quantities of interest. Moreover, droppers surrounding the mast have been shown to be particularlyimportant in dynamic interaction. Ratio of wire impedances and sum of wave velocities also appeared tobe dimensioning quantities for catenary design. The second contribution was to reduce epistemic uncertaintylinked with model parameters such as catenary damping, contact stiffness and element size. Thefinal contribution was to use the model in a configuration with random parameters. An initial step was tostatistically characterise physical catenary parameters using available measurements. From this randommodel, ranking of uncertainties using Sobol indices on static and dynamic criteria was shown to be possible.An absence of correlation between geometric and dynamic criteria was also found, which has notableimplications for maintenance policies. The high number of sensitivity studies also gave the occasion tohighlight the maturity of simulation tool and propose directions for further work on design, maintenance orcertification of pantographs and catenaries.

Variation in breast cancer risk with mutation position, smoking, alcohol, and chest X-ray history, in the French National BRCA1/2 carrier cohort (GENEPSO)

Abstract: Germline mutations in BRCA1/2 confer a high risk of breast cancer (BC), but the magnitude of this risk varies according to various factors Although controversial, there are data to support the hypothesis of allelic-risk heterogeneity We assessed variation in BC risk according to the location of mutations recorded in the French study GENEPSO Since the women in this study were selected from high-risk families, oversampling of affected women was eliminated by using a weighted Cox-regression model Women were censored at the date of diagnosis when affected by any cancer, or the date of interview when unaffected A total of 990 women were selected for the analysis: 379 were classified as affected, 611 as unaffected For BRCA1, there was some evidence of a central region where the risk of BC is lower (codons 374–1161) (HR = 059, P = 004) For BRCA2, there was a strong evidence for a region at decreased risk (codons 957–1827) (HR = 035, P = 0005) and for one at increased risk (codons 2546–2968) (HR = 356, P = 001) Moreover, we found an important association between radiation exposure from chest X-rays and BC risk (HR = 429, P < 10−3) and a positive association between smoking more than 21 pack-years and BC risk (HR = 209, P = 004) No significant variation in BC risk associated with chest X-ray exposure, smoking, and alcohol consumption was found according to the location of the mutation in BRCA1 and BRCA2 Our findings are consistent with those suggesting that the risk of BC is lower in the central regions of BRCA1/2 A new high-risk region in BRCA2 is described Taking into account environmental and lifestyle modifiers, the location of mutations might be important in the clinical management of BRCA mutation carriers