scholarly journals A Large-Scale CNN Ensemble for Medication Safety Analysis

Author(s):  
Liliya Akhtyamova ◽  
Andrey Ignatov ◽  
John Cardiff
Author(s):  
Robert Zboray ◽  
Domenico Paladino ◽  
Olivier Auban

The present paper discusses experiments carried out to examine mixing of different gases (steam, air) and the evolution their distributions in large-scale, multi compartment geometry imitating nuclear reactor containment compartments. The flow and the mixing process in the experiments are driven by plumes and jets representing source structures with different momentum-to-buoyancy strength. The time evolution of the relevant parameters like gas concentrations, velocities and temperatures are followed using dedicated instrumentation. The data obtained is meant to be used for the validation and development of high-resolution, mainly CFD based, 3D computational tools for nuclear reactor containment safety analysis.


Author(s):  
Elisabeth Keim ◽  
Roland Hertlein ◽  
Ulf Ilg ◽  
Gu¨nter Ko¨nig ◽  
Norbert Schlu¨ter ◽  
...  

During the design stage of the today operating German PWRs, one major design target was to manage the materials ageing behavior of the ferritic reactor pressure vessel (RPV) steel in oder to prevent a brittle fracture of the RPV under all possible loads. Very conservative thermal hydraulic input data were used in this context for the assessment of loss of coolant accidents. Today more realistic thermal hydraulic analyses based on large scale experimental results are available as well as more sophisticated fracture mechanics methods to assess postulated flaws. Using these tools an additional joint analysis of six German PWR RPVs is performed. A fully representative spectrum of all possible large and small break loss of coolant accidents is investigated. Locations of interest are the irradiated RPV core beltline region as well as those regions with negligible irradiation but higher loading, like the RPV MCL nozzles and the flange to cylinder transition area. The thermal hydraulic work comprises global system analyses with subsequent local analysis considering mixing phenomena like plume forming below the injecting nozzles. Dependent on the location of the postulated flaw (core or nozzle region), the postulated leak size is differing. In the core weld region medium leak sizes (100 to 200 cm2) with subsequent injection into the cold leg lead to dominating loading, whereas in the nozzle the small leak sizes (3 to 20 cm2) with injection into the hot leg are more important. This is due to the higher pressure at smaller leak sizes and the larger thermal stresses caused by the high temperature of the nozzle flange and the low temperature of the injected ECCS-water. But independent of the number of transients it turned out that all load paths of the postulated flaws and the investigated leak sizes show a similar behavior. As the result of this additional joint safety analysis of six German PWR RPVs with different injection modes, a brittle fracture of all RPV regions can be excluded with sufficient safety margin.


2015 ◽  
Vol 58 ◽  
pp. 363-379 ◽  
Author(s):  
Paul St-Aubin ◽  
Nicolas Saunier ◽  
Luis Miranda-Moreno

2019 ◽  
Vol 48 (3) ◽  
pp. 253-259
Author(s):  
Ádám Bényei ◽  
Gabor Vida ◽  
Krisztián Pintér ◽  
Zsolt Szalay ◽  
György Ágoston

Cybersecurity is becoming more and more relevant. Autonomous vehicles handle large amounts of data and can connect to more and more existing devices, smartphones, tablets, or even other cars and systems. This poses the risk of unauthorized access to data. Theoretically cars have separate computer units, operate in isolation, and are not connected, so there is less possibility to be attacked. However if the vehicles are interconnected, hackers can have easier access to personal data. They can get information about the location of the car owner, their typical trips, and, for example, allow an intruder to know when the tracked person is not at home. Furthermore it can also be happened that the vehicle operation is maliciously disturbed, which can result in a security risk for the passengers. In extreme cases, computer terrorist attacks can also be prepared - large-scale interventions on roads can lead to chaos across a region or country. In accordance with the introduced threats, it is a crucial objective of this research to indicate specific methods, which can help the industry to evaluate and prepare for these kinds of attacks in a proper way.


2021 ◽  
Author(s):  
Biruk E. Tegicho ◽  
Tadilo E. Bogale ◽  
Abdullah Eroglu ◽  
William Edmonson
Keyword(s):  

1999 ◽  
Vol 173 ◽  
pp. 243-248
Author(s):  
D. Kubáček ◽  
A. Galád ◽  
A. Pravda

AbstractUnusual short-period comet 29P/Schwassmann-Wachmann 1 inspired many observers to explain its unpredictable outbursts. In this paper large scale structures and features from the inner part of the coma in time periods around outbursts are studied. CCD images were taken at Whipple Observatory, Mt. Hopkins, in 1989 and at Astronomical Observatory, Modra, from 1995 to 1998. Photographic plates of the comet were taken at Harvard College Observatory, Oak Ridge, from 1974 to 1982. The latter were digitized at first to apply the same techniques of image processing for optimizing the visibility of features in the coma during outbursts. Outbursts and coma structures show various shapes.


1994 ◽  
Vol 144 ◽  
pp. 29-33
Author(s):  
P. Ambrož

AbstractThe large-scale coronal structures observed during the sporadically visible solar eclipses were compared with the numerically extrapolated field-line structures of coronal magnetic field. A characteristic relationship between the observed structures of coronal plasma and the magnetic field line configurations was determined. The long-term evolution of large scale coronal structures inferred from photospheric magnetic observations in the course of 11- and 22-year solar cycles is described.Some known parameters, such as the source surface radius, or coronal rotation rate are discussed and actually interpreted. A relation between the large-scale photospheric magnetic field evolution and the coronal structure rearrangement is demonstrated.


2000 ◽  
Vol 179 ◽  
pp. 205-208
Author(s):  
Pavel Ambrož ◽  
Alfred Schroll

AbstractPrecise measurements of heliographic position of solar filaments were used for determination of the proper motion of solar filaments on the time-scale of days. The filaments have a tendency to make a shaking or waving of the external structure and to make a general movement of whole filament body, coinciding with the transport of the magnetic flux in the photosphere. The velocity scatter of individual measured points is about one order higher than the accuracy of measurements.


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