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Due to the current events related to Covid-19, the conference originally planned for July 2020 has been postponed to April 7-9, 2021.The conference will be organized virtually by videoconference. ORAL; International audience; In this paper, a study of UWB receivers in terms of detection theory is presented. The UWB radar which is presented in many works previously [1]-[3] has many applications. For road UWB radar application, the receiver based on correlation is the optimum receiver [4]. In fact, it maximizes the probability of detection. We will consider, in this study, a correlator receiver based on a threshold detection method. As in narrowband [5] [6], we will describe the theoretical study that evaluates the performance of the UWB receiver based on correlation in terms of detection and false alarm probabilities. Then a study of curves showing threshold receiver operating characteristics (ROC system), based on correlation and destined to be used for a UWB radar is presented. The study is original because it is presented for the first time in a UWB radar system.

Le soutien aux économies émergentes au moment de la Covid-19 sera le prochain défi mondial. La coopération internationale devra créer des moyens durables de remédier aux inégalités et de renforcer la gouvernance mondiale.

Many countries around the world have chosen lockdown and restrictions on people's mobility as the main strategies to combat the COVID-19 pandemic. These actions have significantly affected environmental noise and modified urban soundscapes, opening up an unprecedented opportunity for research in the field. In order to enable these investigations to be carried out in a more harmonized and consistent manner, this paper makes a proposal for a set of indicators that will enable to address the challenge from a number of different approaches. It proposes a minimum set of basic energetic indicators, and the taxonomy that will allow their communication and reporting. In addition, an extended set of descriptors is outlined which better enables the application of more novel approaches to the evaluation of the effect of this new soundscape on people's subjective perception.

Year 2020 will mark History, with the emergence of the new Covid-19 virus, and more importantly, the consequent political decisions to apply freedom restriction at such a largescale. Identifying the human behaviours during this extraordinary period represents a unique opportunity to both improve our fundamental knowledge and to improve future management of similar issues. Throughout almost all the duration of the French lockdown (from March 24, 2020 to May 10, 2020), we carried out an online survey on more than 12,000 individuals well distributed over the country. This online survey was performed by using both Lime-Survey and Google Forms services and was addressed to adults living in France. Statistical analyses combined classical inferential approach, mapping, clustering and text mining. The results showed that a significant part of the population moved out just before the lockdown (around 10% of our sample) and we highlighted three different profiles of participants. The results emphasised that the lockdown measures compliance was lower in two cases: (i) an unfavourable living environment (referring to social and economic inequity) associated with a high feeling of fear and a lack of trust towards Governmental measures; or (ii) the feeling that the risk was low due to the fact that others complied with the measures. In case a similar situation should occur again, it is recommended that Governments broadcast clear speeches to improve trust, limit fear and increase cooperative behaviours.

Part 5: Autonomous Agents; International audience; Autonomous Vehicles (AVs) can potentially reduce the accident risk while a human is driving. They can also improve the public transportation by connecting city centers with main mass transit systems. The development of technologies that can provide a sense of security to the passenger when the driver is missing remains a challenging task. Moreover, such technologies are forced to adopt to the new reality formed by the COVID-19 pandemic, as it has created significant restrictions to passenger mobility through public transportation. In this work, an image-based approach, supported by novel AI algorithms, is proposed as a service to increase autonomy of non-fully autonomous people such as kids, grandparents and disabled people. The proposed real-time service, can identify family members via facial characteristics and efficiently ignore face masks, while providing notifications for their condition to their supervisor relatives. The envisioned AI-supported security framework, apart from enhancing the trust to autonomous mobility, could be advantageous in other applications also related to domestic security and defense.

This paper analyses the changes on the maritime network before and after the Covid-19 outbreak. Using a large sample of vessel movements between ports, we show a decrease in the global maritime connectivity and significant differences between ports and inter-port links. Furthermore, we find that Covid-19 mitigation measures implemented by governments affected regional port hierarchies differently, with a reduction in port concentration in Europe and Africa and an increase in Asia and North America. Globally, very large ports and small but densely inter-connected ones resisted better to the crisis than the others, while small transshipment hubs and bridges appear to have been more negatively impacted. These findings have implications for the design of more resilient port strategies and transport policies by states and firms.

In response to insufficient understanding of the determinants of change in e-shopping behaviors during the COVID-19 pandemic in developing countries, this paper used the data from 355 respondents, collected in Hanoi during the social distancing period (April 2020), to explore the factors associated with shopping online more frequently (i.e., representing the growth of e-shopping) for five product types (food, medical products, clothing, electronics, and books) in Hanoi, Vietnam. The results showed that nearly 80% of the respondents engaged in e-shopping more frequently than they did before the outbreak of COVID-19. As regards shopping online more frequently in general (i.e., for at least one product type), females were more likely to do so. In-store shopping enjoyment and a decrease in income were a facilitator and a deterrent, respectively. Regarding specific product types, completely working from home had a positive association with more frequent e-purchasing for electronics. Fear of disease encouraged higher frequencies of e-shopping for food and medical products. Notably, the shortage of physical supply was not a determinant of buying any product type online more frequently. As for the implications of our findings, supporting and encouraging low-income shoppers, older persons, and females to engage in e-shopping is necessary to limit the detrimental effects of the pandemic on their lives. The growth of internet purchasing expresses a need to manage the development of urban delivery services, to limit the uncontrolled proliferation of motorcycles. E-shopping requires delivery to complete the online-to-offline process; therefore, protecting the health of delivery drivers to ensure the safety of the whole online shopping process would be necessary.

Many countries around the world have chosen lockdown and restrictions on people’s mobility as the main strategies to combat the COVID-19 pandemic. These actions have significantly affected environmental noise and modified urban soundscapes, opening up an unprecedented opportunity for research in the field. In order to enable these investigations to be carried out in a more harmonized and consistent manner, this paper makes a proposal for a set of indicators that will enable to address the challenge from a number of different approaches. It proposes a minimum set of basic energetic indicators, and the taxonomy that will allow their communication and reporting. In addition, an extended set of descriptors is outlined which better enables the application of more novel approaches to the evaluation of the effect of this new soundscape on people’s subjective perception.

During the first wave of the COVID-19 pandemic, some French regions were more affected than others. To relieve those areas most affected, the French government organized transfers of critical patients, notably by plane or helicopter. Our objective was to investigate the impact of such transfers on the pulse oximetric saturation (SpO2)-to-inspired fraction of oxygen (FiO2) ratio among transferred critical patients with COVID-19. We conducted a retrospective study on medical and paramedical records. The primary endpoint was the change in SpO2/FiO2 during transfers. Thirty-eight patients were transferred between 28 March and 5 April 2020, with a mean age of 62.4 years and a mean body mass index of 29.8 kg/m2. The population was 69.7% male, and the leading medical history was hypertension (42.1%), diabetes (34.2%), and dyslipidemia (18.4%). Of 28 patients with full data, we found a decrease of 28.9 points in SpO2/FiO2 (95% confidence interval, 5.8 to 52.1, p = 0.01) between the starting and the arrival intensive care units (SpO2/FiO2, 187.3 ± 61.3 and 158.4 ± 62.8 mmHg, respectively). Air medical transfers organized to relieve intensive care unit teams under surging conditions during the first COVID wave were associated with significant decreases in arterial oxygenation.

_; This proposal adopts a holistic approach to strategic transport investment by discussing the wider economic impacts (WEIs) analysis method in terms of several dominant and emerging methods. The WEIs analysis goes beyond the effects captured in a standard cost-benefit analysis (CBA). A CBA addresses the market for transport services and infrastructure access but neglects the wider impacts on other markets. These wider impacts usually relate to agglomeration, market power, and the behavioral adaptions of firms and households. The high uncertainty in land use changes indicates that WEIs tend to occur in different forms on multiple spatial scales, varying by place and time. Additionally, some activities, such as education, have no direct market value, but may indirectly contribute to the overall economic output and human capital development in cities and regions. Given that the conventional elasticity methods are not goal oriented, it is important to ensure that the WEIs analysis accounts for the stakeholder-specific costs and benefits. Assuming that it is possible to consider all WEIs through theoretical models, major efforts should focus on establishing and maintaining appropriate methodologies and tools. The social and environmental data needed to address biodiversity issues should also be improved and promoted. Complementary to the WEIs, understanding how the behavior of agents changes in response to the new transport options will help clarify the long-term implications of transportation. This will suggest new strategies (territorial appropriation), approaches/ techniques to feasibility, and ?place-based? interrelations, that is, specific interrelations in places. This last aspect is especially important in the current context of the COVID-19 pandemic, which has affected and will likely change transportation behaviors and transport demand in the dynamic future.