Enhance Sample Efficiency and Robustness of End-to-end Urban Autonomous Driving via Semantic Masked World Model

End-to-end autonomous driving provides a feasible way to automatically maximize overall driving system performance by directly mapping the raw pixels from a front-facing camera to control signals. Recent advanced methods construct a latent world model to map the high dimensional observations into compact latent space. However, the latent states embedded by the world model proposed in previous works may contain a large amount of task-irrelevant information, resulting in low sampling efficiency and poor robustness to input perturbations. Meanwhile, the training data distribution is usually unbalanced, and the learned policy is hard to cope with the corner cases during the driving process. To solve the above challenges, we present a semantic masked recurrent world model (SEM2), which introduces a latent filter to extract key task-relevant features and reconstruct a semantic mask via the filtered features, and is trained with a multi-source data sampler, which aggregates common data and multiple corner case data in a single batch, to balance the data distribution. Extensive experiments on CARLA show that our method outperforms the state-of-the-art approaches in terms of sample efficiency and robustness to input permutations.Comment: 11 pages, 7 figures, 1 table, submitted to Deep RL Workshop 202

Efficacy and Affecting Factors of 131I Thyroid Remnant Ablation After Surgical Treatment of Differentiated Thyroid Carcinoma

Purpose: Radioiodine (131I) thyroid remnant ablation is an important treatment of differentiated thyroid carcinoma (DTC) and various factors affecting its efficacy have been reported but not well defined. The aim of our study was to evaluate the efficacy and the affecting factors of 131I ablation after total or near-total thyroidectomy in a relative large DTC cohort.Methods: 261 DTC patients with negative thyroglobulin antibody received 100–200 mCi 131I for thyroid remnant ablation after total or near-total thyroidectomy between January 2012 and October 2015 in our hospital. The efficacy and affecting factors of 131I ablation therapy were retrospectively investigated.Results: The success rate of the first 131I thyroid remnant ablation was 65.90%. Univariate analysis demonstrated that larger tumor size, higher level of pre-ablation stimulated thyroglobulin (sTg), intermediate to high risk stratification for recurrence, and lymph node and distant metastases were associated with a lower success rate of the first 131I ablation (all p < 0.05). Multivariate logistic regression analysis showed that tumor size, pre-ablation sTg, and lymph node and distant metastases were independent factors affecting the efficacy of the first 131I ablation. Areas under receiver operating characteristic curves for sTg, sTg/TSH ratio, and tumor size to predict unsuccessful ablation were 0.831, 0.824, and 0.648, respectively. The threshold values were 4.595 ng/ml, 0.046 mg/IU, and 1.350 cm, respectively. The sensitivities were 95.51, 96.63, and 73.03% and the specificities were 64.54, 61.63, and 49.41%, respectively. The excellent response (ER) ratio of the successful group was significantly higher than that of the unsuccessful group.Conclusions: The efficacy of the first 131I thyroid remnant ablation after surgical treatment of DTC is well demonstrated, and tumor size, pre-ablation sTg, lymph node, and distant metastases are independent factors affecting its efficacy

Dégradation atmosphérique des COVs : Isoprène et ses produis d'ozonolyse, une cétone perfluorée et des cétones à longue chaine

Volatile organic compounds (VOCs) constitute a major gas pollutants emitted from both human and biogenic activities. They have a major influence on the chemistry of the troposphere impacting human health, air quality and global climate change. In the present work, the newly built outdoor atmospheric simulation chamber-HELIOS at CNRS-ICARE (Orléans, France) is a 90 m3 Teflon-FEP chamber, that allows the kinetics and mechanistic investigations of ozonolysis of isoprene, methacrolein and methyl vinyl ketone under dark concdition and photolysis of perfluoro- (PF-2M3P) and non-fluorinated 2-methyl-3-pentanone (2M3P) under natural irradiation conditions. In addition, the photolysis of PF-2M3P was also conducted in one 3.4 m3 moveable chamber. In order to determine the photolysis rate of PF-2M3P and 2M3P, their absorption cross sections were measured using an absorption cell coupled with one UV-visible spectrophotometer.In addition, two other simulation chambers: the 7.3 m3 indoor chamber-CSA and 200 L indoor chamber at CNRS-ICARE (Orléans, France) allow kinetics and mechanistic investigations of OH and Cl reactions with three long chain ketones: 2M3P, 3M2P (3-methyl-2-pentanone) and 4M2P (4-methyl-2-pentanone). In addition, a pulsed laser photolysis-laser induced fluorescence (PLP-LIF) system was used to measure the first temperature dependence of the rate constants for the reactions of OH with 2M3P and 3M2P. A wide range and complementary analytical tools have been used to conduct the present work including Fourier Transform Infrared Spectroscopy (FTIR), Gas Chromatograph-Mass spectrometer (GC-MS), Proton Transfer Reaction-Time of Flight-Mass Spectrometer (PTR-ToF-MS), Ultra High speed Liquid Chromatograph-Mass Spectrometer (UHPLC-MS) for measuring VOC/OVOC, Scanning Mobility Particle Sizer-Condensation Particle Counter (SMPS-CPC) for measuring size distribution of SOA.Les composés organiques volatils (COV) constituent des polluants gazeux qui sont émis par des activités humaines et biogéniques. Ils ont une influence majeure sur la chimie de la troposphère qui influe sur la santé humaine, la qualité de l'air et le changement climatique mondial. Dans ce projet, la nouvelle chambre de simulation atmosphérique extérieure - HELIOS au CNRS-ICARE (Orléans, France) est une chambre 90 m3 Teflon-FEP qui permet la cinétique et les études mécaniques de l'ozonolyse de l'isoprène, de la méthacroleine et de la méthylvinylcétone sous la condition sombre et la photolyse du perfluoro- (PF-2M3P) et non fluorée 2-méthyl-3-pentanone (2M3P) dans des conditions d'irradiation naturelles. De plus, la photolyse de PF-2M3P a également été réalisée dans une chambre mobile de 3,4 m3. Pour analyser la photolyse de PF-2M3P et 2M3P, leurs sections transversales d'absorption ont été mesurées par une cellule d'absorption associée à un spectrophotomètre UV-visible.Deux autres chambres de simulation : la chambre intérieure de 7,3 m3-CSA et la chambre intérieure de 200 L au CNRS-ICARE (Orléans, France) permettent des études cinétiques et mécaniques des réactions OH et Cl avec trois cétones à longue chaîne : 2M3P, 3M2P (3 -méthyl-2-pentanone) et 4M2P (4-méthyl-2-pentanone). En outre, Photolyse à Laser Pulsé – Fluorescence Induite par Laser (PLP-LIF) a été utilisé pour mesurer la première dépendance à la température des constantes de vitesse pour les réactions de OH avec 2M3P et 3M2P. Une large gamme et des outils analytiques complémentaires ont été utilisés dans le présent travail, y compris la spectroscopie infrarouge à transformée de Fourier (FTIR), le spectromètre de masse de chromatographie en phase gazeuse (GC-MS), Réaction du transfert de protons- Temps de vol- Spectromètre de masse (PTR-ToF- MS), Spectromètre de masse de chromatographe liquide ultra haute vitesse (UHPLC-MS) pour la mesure de COV / OVOC, Scanning Mobility Particle Sizer-Condensation Particle Counter (SMPS-CPC) pour la mesure de la distribution de taille de SOA

Investigation of the reaction of ozone with isoprene, methacrolein and methyl vinyl ketone using the HELIOS chamber

International audienceThe rate constants for the ozonolysis of isoprene (ISO), methacrolein (MACR) and methyl vinyl ketone (MVK) have been measured using the newly built large volume atmospheric simulation chamber at CNRS-Orleans (France), HELIOS (Chambre de simulation atmospherique a irradiation naturelle d'Orleans). The OH radical yields from the ozonolysis of isoprene, MACR and MVK have also been determined, as well as the gas phase stable products and their yields. The secondary organic aerosol yield for the ozonolysis of isoprene has been tentatively measured in the presence and absence of an OH radical scavenger. The measurements were performed under different experimental conditions with and without adding cyclohexane (cHX) as an OH radical scavenger. All experiments have been conducted at 760 torr of purified dry air (RH < 1%) and ambient temperature (T = 281-295 K). The data obtained are discussed and compared with those from the literature. The use of the HELIOS facility and its associated analytical equipment enables the derivation of kinetic parameters as well as mechanistic information under near realistic atmospheric conditions