Search results for "Wire"
showing 10 items of 1383 documents
When, why, and how to perform wire-based antegrade dissection and reentry technique
2022
Antegrade dissection and reentry (ADR) refers to an attempt to cross a coronary chronic total occlusion (CTO) lesion through wire and/or equipment passage in the subintimal space followed by reentry to the distal true lumen. From the original subintimal tracking and reentry (STAR) technique description by Colombo in 2005, refinement of the technique, improved characteristics of the microcatheters and wires, and better understanding of subadventitial vessel trauma have led to higher success rates, lower complications rates, and improved long-term outcomes. In this chapter, we discuss the technique, its outcomes, and limitations.
Current-induced domain wall motion in nanoscale ferromagnetic elements
2011
The manipulation of a magnetic domain wall (DW) by a spin polarized current in ferromagnetic nanowires has attracted tremendous interest during the last years due to fundamental questions in the fields of spin dependent transport phenomena and magnetization dynamics but also due to promising applications, such as DW based magnetic memory concepts and logic devices. We comprehensively review recent developments in the field of geometrically confined domain walls and in particular current induced DW dynamics. We focus on the influence of the magnetic and electronic transport properties of the materials on the spin transfer effect in DWs. After considering the different DW structures in ferrom…
Wireless HROV Control with Compressed Visual Feedback Using Acoustic and RF Links
2020
AbstractUnderwater cooperative robotics offers the possibility to perform challenging intervention applications, such as recovering archeological objects as within the context of the MERBOTS research project, or grasping, transporting and assembly of big objects, using more than one mobile manipulator, as faced by the TWINBOT project. In order to enhance safety during the intervention, it is reasonable to avoid the umbilical, also giving more mobility to the robots, and enabling a broader set of cooperative movements. Several solutions, based on acoustic, radiofrequency (RF) or Visual Light Communication (VLC) have been proposed for underwater communications in the literature. This paper pr…
DECENTRALIZED SUBSPACE PROJECTION IN LARGE NETWORKS
2018
A great number of applications in wireless sensor networks involve projecting a vector of observations onto a subspace dictated by prior information. Accomplishing such a task in a centralized fashion entails great power consumption, congestion at certain nodes, and suffers from robustness issues. A sensible alternative is to compute such projections in a decentralized fashion. To this end, recent works proposed schemes based on graph filters, which compute projections exactly with a finite number of local exchanges among sensor nodes. However, existing methods to obtain these filters are confined to reduced families of projection matrices or small networks. This paper proposes a method tha…
A TDMA-Based MAC Protocol Supporting Cooperative Communications in Wireless Mesh Networks
2011
This paper proposes a TDMA-based medium access control protocol which enables cooperative communications in multi-hop wireless mesh networks. According to the proposed scheme, each router at the two-hop neighbourhood of each other is allocated to a specific time slot for accommodating either direct or cooperative transmissions in a coordinated manner, controlled by mini-slots which are part of the time slot. Benefiting from the elaborate mini-slot design, channel resources are fairly and efficiently allocated to each router so that no handshake is needed prior to each packet transmission. By providing access priority to cooperative transmission through an optimal relay which is determined b…
A new Scheme for RPL to handle Mobility in Wireless Sensor Networks
2017
Mobile wireless sensor networks (WSNs) are characterised by dynamic changes in the network topology leading to route breaks and disconnections. The IPv6 routing protocol for low power and lossy networks (RPL), which has become a standard, uses the Trickle timer algorithm to handle changes in the network topology. However, neither RPL nor Trickle timer are well adapted to mobility. This paper investigates the problem of supporting mobility when using RPL. It enhances RPL to fit with sensors' mobility by studying two cases. Firstly, it proposes to modify RPL in order to fit with a dynamic and hybrid topology in the context of medical applications. Secondly, it investigates a more general case…
A self-routing protocol for distributed consensus on logical information
2010
In this paper, we address decision making problems, depending on a set of input events, with networks of dynamic agents that have partial visibility of such events. Previous work by the authors proposed so-called logical consensus approach, by which a network of agents, that can exchange binary values representing their local estimates of the events, is able to reach a unique and consistent decision. The approach therein proposed is based on the construction of an iterative map, whose computation is centralized and guaranteed under suitable conditions on the input visibility and graph connectivity. Under the same conditions, we extend the approach in this work by allowing the construction o…
I-RP: Interference Aware Routing Protocol for WBAN
2018
The Wireless Body Sensor Networks (WBSN) have witnessed tremendous research interest because of their wide range of applications (medical and non-medical) in order to improve the quality of life. The healthcare applications of WBSN demands dissemination of patient’s data, reliably and in a timely manner. For this purpose, medical teams may use real-time applications for disseminating critical data such as blood pressure, ECG, and EEG. The critical data packets are highly delay sensitive that must reach intended destination within time constraints. Due to the exchange of real-time and multi-media data, some nodes or links may experience the significant level of interference in the network. C…
Power-constrained sensor selection and routing for cooperative detection in cognitive radios
2012
Given a spectrum-sensing network, a set of active nodes jointly aggregate sensed data at a preset frequency-band and simultaneously route this information to an arbitrarily chosen querying node through a power-constrained multi-hop path. Locally, each sensor node is assumed to be an energy-based detector. This work focuses on deriving algorithms that jointly optimize sensor selection and cooperative detection from which a power-efficient route to the querying node can be established, and then, a tree routing structure spanning the chosen nodes is constructed under a power budget constraint. Sensor information is sequentially aggregated along this optimized routing structure up to the queryi…
Adaptive live video streaming on low-cost wireless multihop networks for road traffic surveillance in smart cities
2021
Abstract Traffic surveillance is an important issue for Intelligent Transportation Systems (ITS) that helps detect incidents automatically, such as wrong-way drivers, still-standing vehicles and jams. Sometimes these systems require a fast and short-term deployment of video cameras. In these cases, ad-hoc networks could be a low-cost and feasible option, but they have poor performance for video delivery. Thus, we propose a smart live video adaptive streaming technique in order to transport video streams from the cameras to the external road traffic monitoring servers. To achieve this goal, these networks need a thorough study in order to analyze video quality under their inherent constraint…