Automated and coordinated vehicles' driving (platooning) is very challenging due to the multi-body control complexity and the presence of unreliable, time-varying wireless Inter-Vehicular Communication (IVC). We propose a novel controller for vehicle platooning based on consensus and analytically demonstrate its stability and dynamic properties. Traditional approaches assume the logical control topology as a constraint fixed a priori, and the control law is designed consequently; our approach makes the control topology a design parameter that can be exploited to reconfigure the controller depending on the needs and scenario characteristics. Furthermore, the controller automatically compensates outdated information caused by network losses and delays. The controller is implemented in PLEXE, a state of the art IVC and mobility simulator that includes basic building blocks for platooning. Analysis and simulations show the controller robustness and performance in several scenarios, including realistic propagation conditions with interference caused by other vehicles. We compare our approach against a controller taken from literature, which is generally considered among the most performing ones. Finally, we test the proposed controller by implementing the real dynamics (engine, transmission, braking systems, etc.) of heterogeneous vehicles in PLEXE and verifying that platoons remain stable and safe regardless of real life impairments that cannot be modeled in the analytic solution. The results show the ability of the proposed approach to maintain a stable string of realistic vehicles with different control-communication topologies even in the presence of strong interference, delays, and fading conditions, providing higher comfort and safety for platoon drivers.

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Automated and coordinated vehicles' driving (platooning) is gaining more and more attention today and it represents a challenging scenario heavily relying on wireless Inter-Vehicular Communication (IVC). In this paper, we propose a novel controller for vehicle platooning based on consensus. Opposed to current approaches where the logical control topology is fixed a priori and the control law designed consequently, we design a system whose control topology can be reconfigured depending on the actual network status. Moreover, the controller does not require the vehicles to be radar equipped and automatically compensates outdated information caused by network delays. We define the control law and analyze it in both analytical and simulative way, showing its robustness in different network scenarios. We consider three different wireless network settings: uncorrelated Bernoullian losses, correlated losses using a Gilbert-Elliott channel, and a realistic traffic scenario with interferences caused by other vehicles. Finally, we compare our strategy with another state of the art controller. The results show the ability of the proposed approach to maintain a stable string of vehicles even in the presence of strong interference, delays, and fading conditions, providing higher comfort and safety for platoon driver

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Purpose The rise of the mean age incremented the occurrence of femur fractures with respect to the past, leading thus to serious consequences, as regards morbidity and socio-economic impact. The direction of the A.O.R.N. Cardarelli of Naples has introduced a DTAP whose aim was the reduction of LOS. The paper aims to discuss this issue. Design/methodology/approach The aim of this paper is to analyze the introduction of DTAP, employing Lean Thinking and Six Sigma methodology based on the DMAIC cycle. To evaluate the effectiveness of DTAP, two groups of patients have been observed for 14 months (before and after the implementation of DTAP). Findings Statistical tests were performed on the groups and graphics were provided to visualize the decrease of LOS (29.9 per cent). The overall population was also divided in subgroups according to six variables potentially influencing LOS. Research limitations/implications Authors considered six variables of influences; yet, others could be taken into account in the future. Practical implications The decrease of costs due to the management of elderly patients with femur fracture, the optimization of care processes in hospitals and a faster recovery for patients is the tangible contribute of DTAP. Originality/value The implementation of DTAP allowed the hospital to obtain a significant reduction of LOS with a consequently decrease of costs alleviating the hospital and the society from the socio-economic burden and the morbidity of this pathology.

Coronary artery disease is one of the most prevalent chronic pathologies in the modern world, leading to the deaths of thousands of people, both in the United States and in Europe. This article reports the use of data mining techniques to analyse a population of 10,265 people who were evaluated by the Department of Advanced Biomedical Sciences for myocardial ischaemia. Overall, 22 features are extracted, and linear discriminant analysis is implemented twice through both the Knime analytics platform and R statistical programming language to classify patients as either normal or pathological. The former of these analyses includes only classification, while the latter method includes principal component analysis before classification to create new features. The classification accuracies obtained for these methods were 84.5 and 86.0 per cent, respectively, with a specificity over 97 per cent and a sensitivity between 62 and 66 per cent. This article presents a practical implementation of traditional data mining techniques that can be used to help clinicians in decision-making; moreover, principal component analysis is used as an algorithm for feature reduction.

We theoretically address the problem of achieving third-order consensus for a platoon of vehicles in the presence of heterogenous time-varying communication delays. A Lyapunov-Krasovkii function is constructed for the stability analysis. Necessary and sufficient conditions are derived to guarantee that all vehicles asymptotically reach the relative acceleration, speed and position according to the spacing policy. Numerical simulations are provided to demonstrate the effectiveness of the theoretical results in different driving conditions and in the presence of external disturbances. © 2015, IFAC (International Federation of Automatic Control) Hosting by Elsevier Ltd. All rights reserved

Cooperative driving is an essential component of future intelligent road systems. It promises greater safety, reducing accidents due to drivers distraction, improved infrastructure utilization, and fuel consumption reduction with platooning applications. Proper platoon management requires Inter-Vehicular Communication (IVC), longitudinal control and lateral control for stability and safety, and proper application protocols protocols and algorithms to manage platoons and perform coordinated maneuvers. This work shows how a longitudinal controller based on distributed consensus can at the same time guarantee stability and performance in regime platoon operation and be at the hearth of maneuvering protocols and algorithms, as it remains stable in face of changes of platoon topology and control gains. The adoption of a single control algorithm for two fundamental tasks greatly simplify the overall design of the system and improves stability and safety as it is not required to switch between different controllers during platoon operation. The theoretical properties are proven in the first part of the paper. The second part of the paper is devoted to its implemented in a state-of-theart mobility and IVC simulator, which is used for an extensive experimental campaign showing the dynamic properties of the system and its performance in a set of typical platoon maneuvers as join, leave and inclusion of a vehicle in the middle of the platoon. All simulations include realistic details of the vehicle dynamics (mass, dimensions, power train dynamics) as well as extremely detailed modeling of the communication network, from 802.11p protocol details, to collisions, packet errors, path loss and fading on the channel, and source-destination based delays.