Acoustic context effects, where surrounding changes in pitch, rate or timbre influence the perception of a sound, are well documented in speech perception, but how they interact with language ...background remains unclear. Using a reverse-correlation approach, we systematically varied the pitch and speech rate in phrases around different pairs of vowels for second language (L2) speakers of English (/i/-/I/) and French (/u/-/y/), thus reconstructing, in a data-driven manner, the prosodic profiles that bias their perception. Testing English and French speakers (n=25), we showed that vowel perception is in fact influenced by conflicting effects from the surrounding pitch and speech rate: a congruent proximal effect 0.2s pre-target and a distal contrastive effect up to 1s before; and found that L1 and L2 speakers exhibited strikingly similar prosodic profiles in perception. We provide a novel method to investigate acoustic context effects across stimuli, timescales, and acoustic domain.
Hydroprocessing stabilization has been assessed using experimental data acquired at transient conditions. These data were obtained from a hydrotreating pilot plant in a wide range of operating ...conditions. It has been found that the stabilization evolution follows a first-order response and could be characterized by a stabilization time τ. A linear model was developed to relate τ to its most influential parameters. The model can then be combined with online transient data to predict the steady-state performance. By testing against new data with other feedstocks, the model has been found to provide a good prediction of the stabilization evolution and the ultimate steady-state hydrotreating performance. It is, hence, possible to “online” calculate the steady-state performance without the need to reach this steady state.
•A continuous lumping model was applied to hydrocracking of VGO.•Experimental data from a pilot plant was used for calibration and validation.•Good results are obtained for a wide range of operating ...conditions and feeds.•A detailed statistical analysis of model parameters is presented.
Process models are a vital tool for the development of industrial hydrocracking units and to drive innovation of process design and novel catalysts. A hydrocracking model, based on the continuous lumping approach, is presented in this work. A zeolite catalyst was used for hydrocracking of pre-treated VGO feeds. The model includes inhibition terms for organic nitrogen and NH3 gas. A total of 74 data points, from experimental runs in a fixed-bed pilot plant, have been used for parameter identification (52 points) and model validation (22 points). The model has been found to provide a good estimation of total residue (>370°C cut) conversion and yield structure (naphtha, kerosene and diesel). A statistical analysis of the 12 model parameters, based on the Eigenvectors of the Hessian has been presented. The impact of the individual parameters on the objective function was thus evaluated. This analysis can help guide future refinement of the model.
Having sufficient grid-forming sources is one of the necessary conditions to guarantee the stability in a power system hosting a very large share of inverter-based generation. The grid-forming ...function has been historically fulfilled by synchronous machines. However, with the appropriate control, it can also be provided by voltage source converters (VSC). This work presents a comparison between two technologies with grid-forming capability: the VSC with a grid-forming control coupled with an adequate energy storage system, and the synchronous condensers (SC). Both devices are compared regarding their inertial response, as well as their contribution to the system strength and short-circuit current for an equivalent capacity expressed in terms of apparent power and inertial reserve. Their behaviour following grid disturbances is assessed through time-domain simulations based on detailed electromagnetic transient (EMT) models. The results show that both devices achieve similar performance in the time-scale of seconds. For shorter time-windows, however, they present a different behavior: the SC ensures a better stiffness in the first tens of ms following the disturbance, while the VSC offers a faster resynchronization.
•Extension of Hydrocracking Single Events Model from paraffins to cyclic species.•Sucessful application to HCK of a real VGO feed.•Model is shown to be useful for an industrial process with real ...feed.•Detailed analysis of reaction kinetic of individual molecular families is presented.
The single events microkinetic modelling approach is extended to include saturated and unsaturated cyclic molecules, in addition to paraffins. The model is successfully applied to hydrocracking (HCK) of an hydrotreated Vacuum Gas Oil (VGO) residue in a pilot plant, under industrial operating conditions, on a commercial bi-functional catalyst. The molecular composition of the VGO feed is obtained by reconstruction based on a combination of analytical data (SIMDIS, GCxGC, mass spectrometryspectrometry). The necessary extensions to the single events methodology, which has previously only been applied to much simpler reacting systems (i.e. HCK of paraffins) are detailed in this work. Feeds typically used in the petrochemical industry typically contain a far more complex mixture of hydrocarbons, including cyclic species (i.e. naphthenes & aromatics). A more complex reaction network is therefore required in order to apply a single events model to such feeds. Hydrogenation, as well as endo- and exo-cyclic reactions have been added to the well-known acyclic β-scission and PCP-isomerization reactions. A model for aromatic ring hydrogenation was included in order to be able to simulate the reduction in aromatic rings, which is an important feature of HCK units. The model was then applied to 8 mass balances with a wide range of residue conversion (20–90%). The single events model is shown to be capable of correctly simulating the macroscopic effluent characteristics, such as residue conversion, yield structure, and weight distribution of paraffinic, naphthenic, and aromatic compounds in the standard cuts. This validates the overall model. The single events model provides far more detail about the fundamental chemistry of the system. This is shown in a detailed analysis of the reaction kinetics. The evolution of molecule size (i.e. carbon number), number of saturated/unsaturated rings, or the ratio of branched and un-branched species can be followed along the reactor. This demonstrates the explanatory power of this type of model. Calculations are performed on the IFPEN high performance computing cluster, with parallelization via MPI (message passing interface). This was very useful in order to reduce time consuming problems especially for the parameter fitting step
Abstract
Objective
To assess the safety and the efficacy of TNF-α antagonists and tocilizumab in patients with Takayasu arteritis (TAK).
Methods
A total of 209 patients with TAK median age 29 years ...(interquartile range 7–62), 186 (89%) females were included. They received either TNF-α antagonists n = 132 (63%) with 172 lines; infliximab (n = 109), adalimumab (n = 45), golimumab (n = 8), certolizumab (n = 6) and etanercept (n = 5) or tocilizumab n = 77 (37%) with 121 lines; i.v. and s.c. in 95 and 26 cases, respectively.
Results
A complete response at 6 months was evidenced in 101/152 (66%) patients on TNF-α antagonists and 75/107 (70%) patients on tocilizumab. Age ≥30 years odds ratio 2.09 (95% CI 1.09, 3.99) was associated with complete response, whereas vascular signs OR 0.26 (95% CI 0.1, 0.65), baseline prednisone ≥20 mg/day OR 0.51 (95% CI 0.28, 0.93) were negatively associated with the complete response to TNF-α antagonists or tocilizumab. During a median follow-up of 36 months, 103 relapses were noted. Supra-aortic branches and thoracic aorta involvement HR 2.44 (95% CI 1.06, 5.65) and 3.66 (1.18, 11.4), respectively and systemic signs at baseline HR 2.01 (95% CI 1.30, 3.11) were significantly associated with relapse. The cumulative incidence of treatment discontinuation and relapse were similar in TNF-α antagonists and tocilizumab. Fifty-eight (20%) adverse effects occurred on biologic targeted therapies 37 (21%) on TNF-α antagonists and 21 (17%) on tocilizumab (P = 0.4), respectively.
Conclusion
This large multicentre study shows high efficacy of biologic targeted treatments in refractory TAK. Efficacy, relapse and drug retention rate were equivalent with TNF-α antagonists and tocilizumab.
•The dominant factors during hydroprocessing stabilization were assessed.•Stabilization time model was constructed using transient data.•Good prediction of steady-state performance from ...transient-state data.
Hydroprocessing stabilization has been assessed using experimental data acquired at transient conditions. These data were obtained from a hydrotreating pilot plant in a wide range of operating conditions. It has been found that the stabilization evolution follows a first-order response and could be characterized by a stabilization time τ. A linear model was developed to relate τ to its most influential parameters. The model can then be combined with online transient data to predict the steady-state performance. By testing against new data with other feedstocks, the model has been found to provide a good prediction of the stabilization evolution and the ultimate steady-state hydrotreating performance. It is, hence, possible to “online” calculate the steady-state performance without the need to reach this steady state.
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