ADAPS: Autonomous Driving Via Principled Simulations

Autonomous driving has gained significant advancements in recent years. However, obtaining a robust control policy for driving remains challenging as it requires training data from a variety of scenarios, including rare situations (e.g., accidents), an effective policy architecture, and an efficient learning mechanism. We propose ADAPS for producing robust control policies for autonomous vehicles. ADAPS consists of two simulation platforms in generating and analyzing accidents to automatically produce labeled training data, and a memory-enabled hierarchical control policy. Additionally, ADAPS offers a more efficient online learning mechanism that reduces the number of iterations required in learning compared to existing methods such as DAGGER. We present both theoretical and experimental results. The latter are produced in simulated environments, where qualitative and quantitative results are generated to demonstrate the benefits of ADAPS.Comment: Accepted to ICRA201

3D view synthesis with inter-view consistency

International audienceIn this paper, we propose a new pipeline to synthesize virtual views by extrapolation. It allows us to generate virtual views far away from each other, each presenting the exact same level of quality. This inter-view consistency is key to seamlessly navigate between viewpoints. Its computational cost is also lower than that of existing approaches. We compare the proposed approach with state-of-the-art methods and show the effectiveness of this new view synthesis pipeline

WarpDriver: context-aware probabilistic motion prediction for crowd simulation

Microscopic crowd simulators rely on models of local interaction (e.g. collision avoidance) to synthesize the individual motion of each virtual agent. The quality of the resulting motions heavily depends on this component, which has significantly improved in the past few years. Recent advances have been in particular due to the introduction of a short-horizon motion prediction strategy that enables anticipated motion adaptation during local interactions among agents. However, the simplicity of prediction techniques of existing models somewhat limits their domain of validity. In this paper, our key objective is to significantly improve the quality of simulations by expanding the applicable range of motion predictions. To this end, we present a novel local interaction algorithm with a new context-aware, probabilistic motion prediction model. By context-aware, we mean that this approach allows crowd simulators to account for many factors, such as the influence of environment layouts or in-progress interactions among agents, and has the ability to simultaneously maintain several possible alternate scenarios for future motions and to cope with uncertainties on sensing and other agent's motions. Technically, this model introduces "collision probability fields" between agents, efficiently computed through the cumulative application of Warp Operators on a source Intrinsic Field. We demonstrate how this model significantly improves the quality of simulated motions in challenging scenarios, such as dense crowds and complex environments

3D view synthesis with inter-view consistency

International audienceIn this paper, we propose a new pipeline to synthesize virtual views by extrapolation. It allows us to generate virtual views far away from each other, each presenting the exact same level of quality. This inter-view consistency is key to seamlessly navigate between viewpoints. Its computational cost is also lower than that of existing approaches. We compare the proposed approach with state-of-the-art methods and show the effectiveness of this new view synthesis pipeline

Infiltration of a photonic crystal fiber with cholesteric liquid crystal and blue phase

Photonic crystal fibers (PCF) have been selectively filled with a cholesteric liquid crystal (ChLC) with special interest in the blue phase (BP) of the liquid crystal. It has been observed thermal tuning of the guided light in the visible region. A dramatically enhance appears when the phase of the liquid crystal changes from cholesteric to blue phase I (BPI). When a thermal range of the blue phase I is achieved, no changes are observed while increasing temperature from BPI through BPII and to the isotropic phase

Electronic, vibrational and magnetic properties of a novel C_{48}N_{12} aza-fullerene

We study the structural, electronic, vibrational and magnetic properties of a novel ${\rm C}_{48}{\rm N}_{12}$ aza-fullerene using density functional theory and restricted Hartree-Fock theory. Optimized geometries and total energy of this fullerene have been calculated. We find that for ${\rm C}_{48}{\rm N}_{12}$ the total ground state energy is about -67617 eV, the HOMO-LUMO gap is about 1.9 eV, five strong IR spectral lines are located at the vibrational frequencies, 461.5 ${\rm cm}^{-1}$, 568.4 ${\rm cm}^{-1}$, 579.3 ${\rm cm}^{-1}$, 1236.1 ${\rm cm}^{-1}$, 1338.9 ${\rm cm}^{-1}$, the Raman scattering activities and depolarization ratios are zero, and 10 NMR spectral signals are predicted. Calculations of diamagnetic shielding factor, static dipole polarizabilities and hyperpolarizabilities of ${\rm C}_{48}{\rm N}_{12}$ are performed and discussed.Comment: published in Chem.Phys.Let

Synthetic and computational studies on the tricarboxylate core of 6,7-dideoxysqualestatin H5 involving a carbonyl ylide cycloaddition–rearrangement

Reaction of diazodiketoesters 17 and 28 with methyl glyoxylate in the presence of catalytic rhodium(II) acetate generates predominantly the 6,8-dioxabicyclo[3.2.1]octanes 29 and 30, respectively. Acid-catalysed rearrangement of the corresponding alcohol 31 favours, at equilibrium, the 2,8-dioxabicyclo[3.2.1]octane skeleton 33 of the squalestatins–zaragozic acids. Force field calculations on the position of the equilibrium gave misleading results. DFT calculations were correct in suggesting that the energy difference between 31 and 33 should be small, but did not always suggest the right major product. Calculation of the NMR spectra of the similar structures could be used to assign the isomers with a high level of confidence

Genome-Wide Analysis of Effectors of Peroxisome Biogenesis

Peroxisomes are intracellular organelles that house a number of diverse metabolic processes, notably those required for β-oxidation of fatty acids. Peroxisomes biogenesis can be induced by the presence of peroxisome proliferators, including fatty acids, which activate complex cellular programs that underlie the induction process. Here, we used multi-parameter quantitative phenotype analyses of an arrayed mutant collection of yeast cells induced to proliferate peroxisomes, to establish a comprehensive inventory of genes required for peroxisome induction and function. The assays employed include growth in the presence of fatty acids, and confocal imaging and flow cytometry through the induction process. In addition to the classical phenotypes associated with loss of peroxisomal functions, these studies identified 169 genes required for robust signaling, transcription, normal peroxisomal development and morphologies, and transmission of peroxisomes to daughter cells. These gene products are localized throughout the cell, and many have indirect connections to peroxisome function. By integration with extant data sets, we present a total of 211 genes linked to peroxisome biogenesis and highlight the complex networks through which information flows during peroxisome biogenesis and function