26 research outputs found

    Intraoperative Beat-to-Beat Pulse Transit Time (PTT) Monitoring via Non-Invasive Piezoelectric/Piezocapacitive Peripheral Sensors Can Predict Changes in Invasively Acquired Blood Pressure in High-Risk Surgical Patients

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    Background: Non-invasive tracking of beat-to-beat pulse transit time (PTT) via piezoelectric/piezocapacitive sensors (PES/PCS) may expand perioperative hemodynamic monitoring. This study evaluated the ability for PTT via PES/PCS to correlate with systolic, diastolic, and mean invasive blood pressure (SBPIBP, DBPIBP, and MAPIBP, respectively) and to detect SBPIBP fluctuations. Methods: PES/PCS and IBP measurements were performed in 20 patients undergoing abdominal, urological, and cardiac surgery. A Pearson’s correlation analysis (r) between 1/PTT and IBP was performed. The predictive ability of 1/PTT with changes in SBPIBP was determined by area under the curve (reported as AUC, sensitivity, specificity). Results: Significant correlations between 1/PTT and SBPIBP were found for PES (r = 0.64) and PCS (r = 0.55) (p < 0.01), as well as MAPIBP/DBPIBP for PES (r = 0.6/0.55) and PCS (r = 0.5/0.45) (p < 0.05). A 7% decrease in 1/PTTPES predicted a 30% SBPIBP decrease (0.82, 0.76, 0.76), while a 5.6% increase predicted a 30% SBPIBP increase (0.75, 0.7, 0.68). A 6.6% decrease in 1/PTTPCS detected a 30% SBPIBP decrease (0.81, 0.72, 0.8), while a 4.8% 1/PTTPCS increase detected a 30% SBPIBP increase (0.73, 0.64, 0.68). Conclusions: Non-invasive beat-to-beat PTT via PES/PCS demonstrated significant correlations with IBP and detected significant changes in SBPIBP. Thus, PES/PCS as a novel sensor technology may augment intraoperative hemodynamic monitoring during major surgery.German Government sponsored ZIM (Zentrales Innovationsprogramm Mittelstand) programPeer Reviewe

    SEVered: Subverting AMD's virtual machine encryption

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    AMD SEV is a hardware feature designed for the secure encryption of virtual machines. SEV aims to protect virtual machine memory not only from other malicious guests and physical attackers, but also from a possibly malicious hypervisor. This relieves cloud and virtual server customers from fully trusting their server providers and the hypervisors they are using. We present the design and implementation of SEVered, an attack from a malicious hypervisor capable of extracting the full contents of main memory in plaintext from SEV-encrypted virtual machines. SEVered neither requires physical access nor colluding virtual machines, but only relies on a remote communication service, such as a web server, running in the targeted virtual machine. We verify the effectiveness of SEVered on a recent A MD SEV-enabled server platform running different services, such as web or SSH servers, in encrypted virtual machines. With these examples, we demonstrate that SEVered reliably and efficiently extracts all memory contents even in scenarios where the targeted virtual machine is under high load

    Safety & security testing of cooperative automotive systems

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    Cooperative behavior of automated traffic participants is one next step towards the goals of reducing the number of traffic fatalities and optimizing traffic flow. The notification of a traffic participant’s intentions and coordination of driving strategies increase the reaction time for safety functions and allow a foresighted maneuver planning. When developing cooperative applications, a higher design complexity has to be handled, as components are distributed over heterogeneous systems that interact with a varying timing behavior and less data confidence. In this paper, we present a solution for the development, simulation and validation of cooperative automotive systems together with an exemplary development flow for safety and security testing

    A Rapid Innovation Framework for Connected Mobility Applications: High Performance Center Connected Secure Systems. Fraunhofer AISEC, EMFT & ESK

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    Connected Mobility Applications help to continuously improve traffic safety and efficiency. Today, much time and effort have to be invested to bring an idea into a safe prototype and to finally launch a reliable product.Software development tools have to adapt to these requirements. They have to support a rapid and continuous development process, that allows to test and validate the distributed application as one overall system. When developing cooperative applications, a higher design complexity has to be handled, as components are distributed over heterogeneous systems that interact with a varying timing behavior and less data confidence. Also, test and validation become more complex. Our Innovation Framework is intended to rapidly bring an idea for a connected application into a prototype so the investment risk for innovative applications is reduced. In this whitepaper we describe the approach of a Rapid InnovationTool Kit that is intended to speed up the development process for connected mobility applications. Thereby, a safe and secure prototype is available at an early development phase to gain experience within field tests that help to rapidly improve the intended application. Our software tool kit is able to find deviations from the specified behaviour and also it can instantly locate and identify erroneous functions within distributed systems. Extensive security tests can then be applied on the implemented application to ensure a secure operation. Another use case for the described testbed is to evaluate communication technologies and to find the most suitable transmission technology for a certain application. For example, short range communication with the 802.11p WLAN technology or the upcoming LTE enhancement LTE-V2X are comparable within specific scenarios. This evaluation can help to reduce the investment risk for the deployment of connected applications

    Tijding en tendens : literatuurwetenschap in de Nederlanden. /

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    Ten Geleide. Het lappendeken. Over literatuurwetenschap in de Nederlanden / Sascha Bru en Anneleen Maaschelein;Deel 1. De tekst en zijn grenzen. Duivelse mechaniek : Narratologie in de Lage Landen / Lars Bernaerts; Omtrent 'Lessen in lyriek'. Structuralisme, poëtica, poststructuralisme in het werk van Bronzwaer / Ulla Mussara-schrøder; Losse eindjes in de literatuurwetenschap van de laatste honderd jaar. Over formele procedés, intertekstualiteit en genre / Douwe Fokkema; 'Glashelder is het geheel niet.' Opvattingen over betekenis in het poëticaonderzoek sinds Oversteegen / Pieter Verstraeten;Deel 2. Grenzen in Context. Literatuursociologie in de Lage Landen / Bart Keunen, Daan Vandenhaute en Laurence Van Nuijs; Voorbij het aperitief. Een overzicht van het wetenschappelijk onderzoek naar uitgeverijen in Nederland en Vlaanderen / Kevin Absillis; Omwegen en allegorieën : interdisciplinariteit en 'cultural analysis' / Joost de Bloois; De blinde vlekken van de historische letterkunde / Jürgen Pieters;Nawoord. Vergelijkende Literatuurwetenschap in België en Nederland / Geert Lernout
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