1,163 research outputs found
Defensive Perception: Estimation and Monitoring of Neural Network Performance under Deployment
In this paper, we propose a method for addressing the issue of unnoticed
catastrophic deployment and domain shift in neural networks for semantic
segmentation in autonomous driving. Our approach is based on the idea that deep
learning-based perception for autonomous driving is uncertain and best
represented as a probability distribution. As autonomous vehicles' safety is
paramount, it is crucial for perception systems to recognize when the vehicle
is leaving its operational design domain, anticipate hazardous uncertainty, and
reduce the performance of the perception system. To address this, we propose to
encapsulate the neural network under deployment within an uncertainty
estimation envelope that is based on the epistemic uncertainty estimation
through the Monte Carlo Dropout approach. This approach does not require
modification of the deployed neural network and guarantees expected model
performance. Our defensive perception envelope has the capability to estimate a
neural network's performance, enabling monitoring and notification of entering
domains of reduced neural network performance under deployment. Furthermore,
our envelope is extended by novel methods to improve the application in
deployment settings, including reducing compute expenses and confining
estimation noise. Finally, we demonstrate the applicability of our method for
multiple different potential deployment shifts relevant to autonomous driving,
such as transitions into the night, rainy, or snowy domain. Overall, our
approach shows great potential for application in deployment settings and
enables operational design domain recognition via uncertainty, which allows for
defensive perception, safe state triggers, warning notifications, and feedback
for testing or development and adaptation of the perception stack
Konjunkturprognose Ostdeutschland und Sachsen 2009/2010: Anhaltende Rezession
Die ostdeutsche Wirtschaft befindet sich weiterhin in einem massiven Abschwung. Gegenwärtig deuten zwar einige Indikatoren, wie das ifo Geschäftsklima fßr die gewerbliche Wirtschaft Ostdeutschlands, daraufhin, dass sich das Tempo der gesamtwirtschaftlichen Schrumpfung vermindert hat, eine Wende in der konjunkturellen Entwicklung zeichnet sich jedoch fßr das laufendende Jahr noch nicht ab. Das preisbereinigte Bruttoinlandsprodukt der ostdeutschen Bundesländer wird 2009 voraussichtlich um 4,9 % und 2010 um 0,3 % zurßckgehen. Fßr die sächsische Wirtschaft wird aufgrund ihrer hÜheren Exportabhängigkeit fßr 2009 ein vergleichsweise stärkerer und fßr 2010 ein etwas schwächerer Rßckgang prognostiziert. Der massive Konjunkturabschwung dßrfte sich zunehmend auch auf dem Arbeitsmarkt bemerkbar machen und zu einem deutlichen Rßckgang der Zahl der Erwerbstätigen fßhren.Konjunktur; Konjunkturprognose; Sachsen; Neue Bundesländer
8E-17 fractional laser frequency instability with a long room-temperature cavity
We present a laser system based on a 48 cm long optical glass resonator. The
large size requires a sophisticated thermal control and optimized mounting
design. A self balancing mounting was essential to reliably reach sensitivities
to acceleration of below < 2E-10 /g in all directions.
Furthermore, fiber noise cancellations from a common reference point near the
laser diode to the cavity mirror and to additional user points (Sr clock and
frequency comb) are implemented. Through comparison to other cavity-stabilized
lasers and to a strontium lattice clock an instability of below 1E-16 at
averaging times from 1 s to 1000 s is revealed
EEG and behavioural correlates of different forms of motor imagery during action observation in rhythmical actions
Recent studies show that participants can engage in motor imagery (MI) and action observation (AO) simultaneously (AO + MI), indicating a capacity for dual action simulation. Here we studied the electrophysiological correlates and behavioural outcomes of two forms of AO + MI, along with pure MI and pure AO control conditions. In synchronised AO + MI, participants imagined performing a rhythmical action in synchrony with an observed distractor action. In contrast in static AO + MI, where the imagery served to conflict with AO, participants imagined holding a static hand posture during AO. Following synchronised AO + MI, rhythmical execution was strongly biased toward the cycle time of the previously observed rhythm (âimitation biasâ), whereas a weaker bias was found following pure MI, and particularly for static AO + MI. In line with these findings, event-related desynchronisation (ERD) in primary sensorimotor and parietal regions was more pronounced in synchronised AO + MI compared to both pure AO and pure MI. These ERD amplitudes were, however, highly similar for static and synchronised AO + MI; suggesting that, regardless of co-represented content, both AO + MI states produced stronger motor activations than single action simulation. In contrast, synchronised AO + MI produced significantly stronger ERD in rostral prefrontal cortex compared to the other three conditions. This specific rostral prefrontal involvement most likely reflected additional cognitive processing for aligning dual action simulations. Together these results provide an important empirical validation of different AO + MI states, in that the imitation bias was strongly modulated by the content of the AO + MI instructions, and that synchronised AO + MI produced stronger behavioural and neurophysiological effects compared to pure AO or MI
C-Reactive Protein Triggers Cell Death in Ischemic Cells
C-reactive protein (CRP) is the best-known acute phase protein. In humans, almost every type of inflammation is accompanied by an increase of CRP concentration. Until recently, the only known physiological function of CRP was the marking of cells to initiate their phagocytosis. This triggers the classical complement pathway up to C4, which helps to eliminate pathogens and dead cells. However, vital cells with reduced energy supply are also marked, which is useful in the case of a classical external wound because an important substrate for pathogens is disposed of, but is counterproductive at internal wounds (e.g., heart attack or stroke). This mechanism negatively affects clinical outcomes since it is established that CRP levels correlate with the prognosis of these indications. Here, we summarize what we can learn from a clinical study in which CRP was adsorbed from the bloodstream by CRP-apheresis. Recently, it was shown that CRP can have a direct effect on blood pressure in rabbits. This is interesting in regard to patients with high inflammation, as they often become tachycardic and need catecholamines. These two physiological effects of CRP apparently also occur in COVID-19. Parts of the lung become ischemic due to intra-alveolar edema and hemorrhage and in parallel CRP increases dramatically, hence it is assumed that CRP is also involved in this ischemic condition. It is meanwhile considered that most of the damage in COVID-19 is caused by the immune system. The high amounts of CRP could have an additional influence on blood pressure in severe COVID-19
Energy system modelling â interactions and synergies in a highly renewable Pan-European power system
It is very likely that the European power supply system will be transformed in the next decades to a low carbon system based almost entirely on Renewable Energy Sources (RES). However, due to the natural fluctuations of the most powerful RES (wind and solar energy), it is also very likely that a significant amount of balancing and controllable backup power capacities will be required to ensure a stable grid operation. This implies high additional investments and operating costs. Therefore this work provides an overview of potential options and possibly more cost-effective alternatives to the installation of costly storage capacities, namely grid expansion, demand side management, an optimised mix between different RES as well as the use of overcapacities. Furthermore, the paper provides an approximation of the maximum RES penetration of the German electricity system in the absence of significant storage capacities. Our calculations show that from a numerical perspective on average approximately half of the load can be met by RES if flexible conventional power stations would provide the remaining electricity demand. However, in a 100% RES scenario a significant amount of storage capacities as well as limited overcapacities are required to ensure a reliable electricity supply
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