Vehicular networks face a number of new challenges, particularly due to the extremely dynamic network topology and the large variable number of mobile nodes. To overcome these problems, an effective solution is to organize the network in a way which will facilitate the management tasks and permit to deploy a wide panoply of applications such as urban sensing applications. This paper presents LTE4V2X, a novel framework for a centralized vehicular network organization using LTE. It takes advantage of a centralized architecture around the eNodeB in order to optimize the clusters management and provide better performances. We studied its performances against a decentralized organization protocol for a well known urban sensing application, FCD application. We analyze the performances of LTE4V2X using NS-3 simulation environment and a realistic urban mobility model. We show that it permits performance improvement by lowering the overhead induced by control messages, reducing the FCD packet losses, as well as enhancing the goodput.

In a recent work [1], we proposed LTE4V2X, a novel framework for a centralized vehicular network organization based on 4G LTE network. We demonstrated the efficiency of our framework for an FCD (Floating Car Data) application. Such applications are based on data collected from vehicles (localization, speed, direction, etc.) in order to feed a traffic management server. In the continuity of this work, this new paper presents two extensions of LTE4V2X. The first one is the multihop extension, which uses multi-hop communications to deal with areas where there is no LTE coverage (e.g. tunnels). The second extension deals with the adaptation of LTE4V2X framework for a dissemination application that aims to disseminate a specific message in a given geographical area. We analyze the performances of LTE4V2X using NS-3 simulation environment and a realistic highway mobility model. The results show that the multi-hop extension leads to an improvement of LTE4V2X performances, for applications based on both data collection and data dissemination.

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Over the last decade, great efforts are invested in reducing emissions of greenhouse gases at a world scale. We should therefore elaborate new global solutions to this type of pollution, in which fleets of vehicles are heavily contributing. In this paper, we propose a novel green architecture for global fleet management that considers the most important actors. The proposed architecture allows to collect useful information from several fleets of vehicles and their environment, and provides real-time services to companies that own one of these fleets. One important service is the calculation of economic itinerary. We propose a new "green" calculation method that is based on an efficient and high precision fuel consumption estimation. Our method uses: (i) topological information such as the elevation variations, source and destination of the trip, (ii) weather conditions, (iii) vehicle's characteristics, and (iv) driver's behavior. We implemented a lightweight traffic management server that provides a real-time service allowing to find the most economic itinerary for vehicles belonging to the fleet. The utilization of such architecture and mechanisms associated with itinerary planning results in a highly green fleet management system.

We propose a technique for treating abdominal aortic aneurysm in which first a minilaparotomy (retroperitoneal) is performed to make a conventional arterial dissection; then, video assistance is used to control the left lumbar arteries and to make the aortic anastomosis. This technique can be performed with no significant laparoscopic capability.The patient was installed in a 20-degree right lateral decubitus. A transverse left 8- to 10-cm abdominal incision was made, followed by separation of the muscular structures. Retroperitoneal control of the proximal aortic neck and of both common iliac arteries was obtained by digital and instrumental dissection. A 30-degree laparoscope was then introduced through a 8- to 12-mm trocar and provided the light and magnification that facilitated the dissection of the posterior wall of the aortic neck and of the left flank of the aneurysm, looking for the lumbar arteries to be clipped. A suspended running suture to make the aorto-prosthetic anastomosis was facilitated by the magnification of the camera, especially during the passage of needles. Between March and September 2001, 32 patients fulfilled the anatomic conditions: an infrarenal aortic neck length of 2 cm or more, absence of hypogastric artery aneurysm, and no need for inferior mesenteric artery reimplantation. In 30 patients, the surgery was performed by using the planned minimally invasive approach, and extension of the incision was necessary in two patients.