Stability of Transportation Networks Under Adaptive Routing Policies

AbstractGrowing concerns regarding urban congestion, and the recent explosion of mobile devices able to provide real-time information to traffic users have motivated increasing reliance on real-time route guidance for the online management of traffic networks. However, while the theory of traffic equilibria is very well-known, much fewer results exist on the stability of such equilibria, especially in the context of adaptive routing policy. In this work, we consider the problem of characterizing the stability properties of traffic equilibria in the context of online adaptive route choice induced by GPS-based decision making. We first extend the recent framework of “Markovian Traffic Equilibria” (MTE), in which users update their route choice at each intersection of the road network based on traffic conditions, to the case of non-equilibrium conditions, while preserving consistency with known existence and uniqueness results on MTE. We then exhibit sufficient conditions on the network topology and the latency functions for those MTEs to be stable in the sense of Lyapunov for a single destination problem. For various more restricted classes of network topologies motivated by the observed properties of travel patterns in the Singapore network, under certain assumptions we prove local exponential stability of the MTE, and derive analytical results on the sensitivity of the characteristic time of convergence on network and traffic parameters. The results proposed in this work are illustrated and validated on synthetic toy problems as well as on the full Singapore road network with real demand and traffic data, and the applicability of our results for online road network analysis, pricing and control is discussed

Shape Animation with Combined Captured and Simulated Dynamics

We present a novel volumetric animation generation framework to create new types of animations from raw 3D surface or point cloud sequence of captured real performances. The framework considers as input time incoherent 3D observations of a moving shape, and is thus particularly suitable for the output of performance capture platforms. In our system, a suitable virtual representation of the actor is built from real captures that allows seamless combination and simulation with virtual external forces and objects, in which the original captured actor can be reshaped, disassembled or reassembled from user-specified virtual physics. Instead of using the dominant surface-based geometric representation of the capture, which is less suitable for volumetric effects, our pipeline exploits Centroidal Voronoi tessellation decompositions as unified volumetric representation of the real captured actor, which we show can be used seamlessly as a building block for all processing stages, from capture and tracking to virtual physic simulation. The representation makes no human specific assumption and can be used to capture and re-simulate the actor with props or other moving scenery elements. We demonstrate the potential of this pipeline for virtual reanimation of a real captured event with various unprecedented volumetric visual effects, such as volumetric distortion, erosion, morphing, gravity pull, or collisions

Transfer Learning for Predictive Models in Massive Open Online Courses

Abstract. Data recorded while learners are interacting with Massive Open Online Courses (MOOC) platforms provide a unique opportunity to build predictive models that can help anticipate future behaviors and develop interventions. But since most of the useful predictive problems are defined for a real-time framework, using knowledge drawn from previous courses becomes crucial. To address this challenge, we designed a set of processes that take advantage of knowledge from both previous courses and previous weeks of the same course to make real time predictions on learners behavior. In particular, we evaluate multiple transfer learning methods. In this article, we present our results for the stopout prediction problem (predicting which learners are likely to stop engaging in the course). We believe this paper is a first step towards addressing the need of transferring knowledge across courses

How human practices have affected vector-borne diseases in the past: a study of malaria transmission in Alpine valleys

This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens

The ecology and evolution of Japanese encephalitis virus

Japanese encephalitis virus (JEV) is a mosquito-borne flavivirus mainly spread by Culex mosquitoes that currently has a geographic distribution across most of Southeast Asia and the Western Pacific. Infection with JEV can cause Japanese encephalitis (JE), a severe disease with a high mortality rate, which also results in ongoing sequalae in many survivors. The natural reservoir of JEV is ardeid wading birds, such as egrets and herons, but pigs commonly play an important role as an amplifying host during outbreaks in human populations. Other domestic animals and wildlife have been detected as hosts for JEV, but their role in the ecology and epidemiology of JEV is uncertain. Safe and effective JEV vaccines are available, but unfortunately, their use remains low in most endemic countries where they are most needed. Increased surveillance and diagnosis of JE is required as climate change and social disruption are likely to facilitate further geographical expansion of Culex vectors and JE risk areas

Use of artificial nutrition near the end of life: Results from a French national population-based study of hospitalized cancer patients

International audienceBackgroundThe use of artificial nutrition, defined as a medical treatment that allows a non‐oral mechanical feeding, for cancer patients with limited life expectancy is deemed nonbeneficial. High‐quality evidence about the use of artificial nutrition near the end of life is lacking. This study aimed (a) to quantify the use of artificial nutrition near the end‐of‐life, and (b) to identify the factors associated with the use of artificial nutrition.MethodsThis was a retrospective cohort study of decedents based on data from the French national hospital database. The study population included adult cancer patients who died in hospitals in France between 2013 and 2016 and defined to be in a palliative condition. Use of artificial nutrition during the last 7 days before death was the primary endpoint.ResultsA total of 398 822 patients were included. The median duration of the last hospital stay was 10 (interquartile range, 4‐21) days. The artificial nutrition was used for 11 723 (2.9%) during the last 7 days before death. Being a man, younger, having digestive cancers, metastasis, comorbidities, malnutrition, absence of dementia, and palliative care use were the main factors associated to the use of artificial nutrition.ConclusionThis study indicates that the use of artificial nutrition near the end of life is in keeping with current clinical guidelines. The identification of factors associated with the use of artificial nutrition, such as cancer localization, presence of comorbidities or specific symptoms, may help to better manage its use

Lessons from end-of-life care among schizophrenia patients with cancer: a population- based cohort study from the French national hospital database Running title: End-of-life care among patients with schizophrenia and cancer

International audienceBackgroundPatients with schizophrenia represent a vulnerable, underserved, and undertreated population who have been neglected in health disparities work. Understanding of end-of-life care in patients with schizophrenia and cancer is poor. We aimed to establish whether end-of-life care delivered to patients with schizophrenia and cancer differed from that delivered to patients with cancer who do not have diagnosed mental illness.MethodsWe did a population-based cohort study of all patients older than 15 years who had a diagnosis of advanced cancer and who died in hospital in France between Jan 1, 2013, and Dec 31, 2016. We divided this population into cases (ie, patients with schizophrenia) and controls (ie, patients without a diagnosis of mental illness) and compared access to palliative care and indicators of high-intensity end-of-life care between groups. In addition to unmatched analyses, we also did matched analyses (matched in terms of age at death, sex, and site of primary cancer) between patients with schizophrenia and matched controls (1:4). Multivariable generalised linear models were done with adjustment for social deprivation, year of death, time from cancer diagnosis to death, metastases, comorbidity, and hospital type (ie, specialist cancer centre vs non-specialist centre).FindingsThe main analysis included 2481 patients with schizophrenia and 222 477 controls. The matched analyses included 2477 patients with schizophrenia and 9896 controls. Patients with schizophrenia were more likely to receive palliative care in the last 31 days of life (adjusted odds ratio 1·61 [95% CI 1·45–1·80]; p<0·0001) and less likely to receive high-intensity end-of-life care—such as chemotherapy and surgery—than were matched controls without a diagnosis of mental illness. Patients with schizophrenia were also more likely to die younger, had a shorter duration between cancer diagnosis and death, and were more likely to have thoracic cancers and comorbidities than were controls.InterpretationOur findings suggest the existence of disparities in health and health care between patients with schizophrenia and patients without a diagnosis of mental illness. These findings underscore the need for better understanding of health inequalities so that effective interventions can be developed for this vulnerable population

4DHumanOutfit: a multi-subject 4D dataset of human motion sequences in varying outfits exhibiting large displacements

This work presents 4DHumanOutfit, a new dataset of densely sampled spatio-temporal 4D human motion data of different actors, outfits and motions. The dataset is designed to contain different actors wearing different outfits while performing different motions in each outfit. In this way, the dataset can be seen as a cube of data containing 4D motion sequences along 3 axes with identity, outfit and motion. This rich dataset has numerous potential applications for the processing and creation of digital humans, e.g. augmented reality, avatar creation and virtual try on. 4DHumanOutfit is released for research purposes at https://kinovis.inria.fr/4dhumanoutfit/. In addition to image data and 4D reconstructions, the dataset includes reference solutions for each axis. We present independent baselines along each axis that demonstrate the value of these reference solutions for evaluation tasks

Ability of the Premise Condition Index to Identify Premises with Adult and Immature Aedes Mosquitoes in Kampong Cham, Cambodia.

Aedes-transmitted diseases, especially dengue, are increasing throughout the world and the main preventive methods include vector control and the avoidance of mosquito bites. A simple Premise Condition Index (PCI) categorizing shade, house, and yard conditions was previously developed to help prioritize households or geographical areas where resources are limited. However, evidence about the accuracy of the PCI is mixed. The current study aimed to contribute to a better understanding of the relevance by collecting data from 2,400 premises at four time points over 1 year in Kampong Cham, Cambodia. Regression models were then used to identify associations between PCI and Aedes adult female mosquitoes and pupae. In addition, receiver operating characteristic curves were used to measure the ability of PCI to identify premises in the top quartile of mosquito abundance. The density of adult Aedes females was positively associated with PCI at the household (ratio of means = 1.16 per point on the PCI scale) and cluster level (ratio of means = 1.54). However, the number of Aedes pupae was negatively associated with PCI at the household level (rate ratio = 0.74) and did not have a statistically significant association at the cluster level. Receiver operating characteristic curves suggest the PCI score had "rather low accuracy" (area under the ROC curve = 0.52 and 0.54) at identifying top-quartile premises in terms of adult female Aedes and pupae, respectively. These results suggest that caution is warranted in the programmatic use of PCI in areas of similar geography and mosquito abundance