Is There Light at the Ends of the Tunnel? Wireless Sensor Networks for Adaptive Lighting in Road Tunnels

Existing deployments of wireless sensor networks (WSNs) are often conceived as stand-alone monitoring tools. In this paper, we report instead on a deployment where the WSN is a key component of a closed-loop control system for adaptive lighting in operational road tunnels. WSN nodes along the tunnel walls report light readings to a control station, which closes the loop by setting the intensity of lamps to match a legislated curve. The ability to match dynamically the lighting levels to the actual environmental conditions improves the tunnel safety and reduces its power consumption. The use of WSNs in a closed-loop system, combined with the real-world, harsh setting of operational road tunnels, induces tighter requirements on the quality and timeliness of sensed data, as well as on the reliability and lifetime of the network. In this work, we test to what extent mainstream WSN technology meets these challenges, using a dedicated design that however relies on wellestablished techniques. The paper describes the hw/sw architecture we devised by focusing on the WSN component, and analyzes its performance through experiments in a real, operational tunnel

Quantitative assessment of HCC wash-out on CT is a predictor of early complete response to TACE

OBJECTIVES: To investigate the predictive value of four-phase contrast-enhanced CT (CECT) for early complete response (CR) to drug-eluting-bead transarterial chemoembolization (DEB-TACE), with a particular focus on the quantitatively assessed wash-in and wash-out. METHODS: A retrospective analysis of preprocedural CECTs was performed for 129 HCC nodules consecutively subjected to DEB-TACE as first-line therapy. Lesion size, location, and margins were recorded. For the quantitative analysis, the following parameters were computed: contrast enhancement ratio (CER) and lesion-to-liver contrast ratio (LLC) as estimates of wash-in; absolute and relative wash-out (WO(abs) and WO(rel)) and delayed percentage attenuation ratio (DPAR) as estimates of wash-out. The early radiological response of each lesion was assessed by the mRECIST criteria and dichotomized in CR versus others (partial response, stable disease, and progressive disease). RESULTS: All quantitatively assessed wash-out variables had significantly higher rates for CR lesions (WO(abs) p = 0.01, WO(rel) p = 0.01, and DPAR p = 0.00002). However, only DPAR demonstrated an acceptable discriminating ability, quantified by AUC = 0.80 (95% CI0.73–0.88). In particular, nodules with DPAR ≥ 120 showed an odds ratio of 3.3(1.5–7.2) for CR (p = 0.0026). When accompanied by smooth lesion margins, DPAR ≥ 120 lesions showed a 78% CR rate at first follow-up imaging. No significative association with CR was found for quantitative wash-in estimates (CER and LLC). CONCLUSIONS: Based on preprocedural CECT, the quantitative assessment of HCC wash-out is useful in predicting early CR after DEB-TACE. Among the different formulas for wash-out quantification, DPAR has the best discriminating ability. When associated, DPAR ≥ 120 and smooth lesion margins are related to relatively high CR rates. KEY POINTS: • A high wash-out rate, quantitatively assessed during preprocedural four-phase contrast-enhanced CT (CECT), is a favorable predictor for early radiological complete response of HCC to drug-eluting-bead chemoembolization (DEB-TACE). • The arterial phase of CECT shows great dispersion of attenuation values among different lesions, even when a standardized protocol is used, limiting its usefulness for quantitative analyses. • Among the different formulas used to quantify the wash-out rate (absolute wash-out, relative wash-out, and delayed percentage attenuation ratio), the latter (DPAR), based only on the delayed phase, is the most predictive (AUC = 0.80), showing a significant association with complete response for values above 120

A multi-element psychosocial intervention for early psychosis (GET UP PIANO TRIAL) conducted in a catchment area of 10 million inhabitants: study protocol for a pragmatic cluster randomized controlled trial

Multi-element interventions for first-episode psychosis (FEP) are promising, but have mostly been conducted in non-epidemiologically representative samples, thereby raising the risk of underestimating the complexities involved in treating FEP in 'real-world' services

Functional data modeling and monitoring applied to particleboard manufacturing

Density of particleboards strongly affects its functional properties. In this paper we show that appropriate statistical methods aimed at monitoring the entire VDP shape, instead of some specific features, can improve the overall quality of the produced boards. The proposed method is based on recent literature on profile monitoring, which suggests to firstly model the profile via functional data and then design appropriate multivariate control charts for monitoring coefficients of the functional data model. The model combines BSpline functions as regressors and a small-scale model for dealing with the autocorrelated errors. Alternative strategies for placing the Spline knots are made. A performance comparison study based on real data is carried out to show that the proposed approach outperforms traditional methods considered in the industrial practice

Towards an automated framework to instantiate virtual networks in OpenFlow-based infrastructures

The explosion of cloud applications and data-centres technologies has recently renewed the interest of both academic and industrial research community on network virtualisation techniques. The increasing availability of programmable network devices and the pervasive adoption of a software-defined networking approach in all segments of the network are paving the way toward novel virtualisation approaches which aim at improving network management operations while guaranteeing a better utilisation of resources especially when compared to traditional overlay-based techniques widely used in data-centre settings. In this paper, the experience gained by the authors in the development and deployment of an innovative network virtualisation framework on an OpenFlow-based programmable experimental facility is provided and discussed in detail. Despite its specific application to a Future Internet testbed scenario, the proposed architecture is a first step toward a completely automatic management of virtual networks in OpenFlow-based software-defined networks

Generalizing virtual network topologies in OpenFlow-based networks

Network Virtualization (NV) is one of the most promising technique to enable innovation in today's network. A recent approach toward NV has been proposed through FlowVisor, whose aim is to leverage on the specific features of an OpenFlow-controlled network to share the same hardware forwarding plane among multiple logical networks. However, FlowVisor lacks some features to enable a full implementation of a NV architecture: the virtual topologies that can be established are restricted to subsets of the physical topology and it has no way for two slices to share flowspace and simultaneously prevent them from interfering with each other's traffic. In this work, an innovative system called ADVisor (ADvanced FlowVisor) which enhances FlowVisor while overcoming its major constraints is presented and a set of experimental results discussed to demonstrate its capability to provide an effective support toward a Network Virtualization architecture

A datapath-centric virtualization mechanism for OpenFlow networks

Abstract: The adoption of a robust and scalable network virtualization framework is a key requirement in order to make the vision of a shareable network infrastructure a reality. To this aim, one of the most suitable approaches is the one which takes advantage of the emerging paradigm of Software-Defined Networking (SDN) and OpenFlow, its de-facto standard. Several virtualization frameworks have been proposed in the last few years, however, they are either based on proxy-based solutions that raises scalability and robustness issues (FlowVisor), or they rely on a simplified view of the data path (generally based on Open vSwitch instances) that have little chances to be adopted in production network settings. This paper presents a novel OpenFlow-based network virtualization mechanism exploiting a recent open-source data path project named extensible Data path Daemon (xDPd), the proposed multi-platform data path is based on a robust distributed virtualization architecture that is able to run on multi-version OpenFlow switch network scenarios, has a minimal overhead from a performance point of view and can be easily ported on several hardware platforms via xDPd libraries

An Approach to Exposing and Sharing Network Services in Software-Defined Networking

The ecosystem of SDN controllers and programmable devices is extremely fragmented: a number of controller platforms and companion tools is available, each of them based on a very different set of features. Moreover, most of the SDN controller frameworks provide a limited set of functionalities to applications that can be deployed on top (usually leveraging on a set of northbound APIs