8,410 research outputs found
XMILE:An XML-based approach for programmable networks
In this paper we describe an XML-based platform for dynamic active node policy updates. XML supports the definitionof specific policy languages, their extension to satisfy new needs and the management of deployed policies on differentactive nodes. We show an example of the management of router packet forwarding policies where the XML policiesthat drive the packet routing are updated at run-time on the active nodes depending on the network status. The platformdecouples policy management, which is handled through XML interpretation, from packet forwarding that, forperformance reasons has to be implemented in more efficient languages
Theoretical study on the protonation of AZA-aromatics
The protonation of azanaphthalenes and azabenzenes has been studied theoretically using CNDO/2 wavefunctions and perturbation theory in order to examine the correlation between pKa values and quantum-mechanical quantities
Liquid-grain mixing suppresses droplet spreading and splashing during impact
Would a raindrop impacting on a coarse beach behave differently from that
impacting on a desert of fine sand? We study this question by a series of model
experiments, where the packing density of the granular target, the wettability
of individual grains, the grain size, the impacting liquid, and the impact
speed are varied. We find that by increasing the grain size and/or the
wettability of individual grains the maximum droplet spreading undergoes a
transition from a capillary regime towards a viscous regime, and splashing is
suppressed. The liquid-grain mixing is discovered to be the underlying
mechanism. An effective viscosity is defined accordingly to quantitatively
explain the observations
Crater formation during raindrop impact on sand
After a raindrop impacts on a granular bed, a crater is formed as both drop
and target deform. After an initial, transient, phase in which the maximum
crater depth is reached, the crater broadens outwards until a final steady
shape is attained. By varying the impact velocity of the drop and the packing
density of the bed, we find that avalanches of grains are important in the
second phase and hence, affect the final crater shape. In a previous paper, we
introduced an estimate of the impact energy going solely into sand deformation
and here we show that both the transient and final crater diameter collapse
with this quantity for various packing densities. The aspect ratio of the
transient crater is however altered by changes in the packing fraction.Comment: 9 pages, 9 figure
Self-Organization in Peer-to-Peer Systems
Peer-to-Peer Systems are about community-based cooperations. The peers share responsibilities and benefits by cooperating in a distributed and decentralized environment. To carry out tasks sensibly, however, a more or less rigid order is required for efficiency and reliability reasons. This order can be partially imposed from the outside, for example within so-called "structed" Peer-to-Peer systems. A common approach here is the use of Distributed Hash Tables. Alternatively, Peer-to-Peer systems can be "unstructured" in the sense that an useful order emerges from own internal processes. Unstructured and structured Peer-to-Peer systems rely both on a more or less decentralized overlay management. Self-organization, therefore, is a key to the success of Peer-to-Peer systems in various forms. This presentation gives an overview of the role of self-organization in Peer-to-Peer systems
Diazanaphthalenes: A 13C NMR investigation on the site of protonation and pKa values
The pH dependence of the 13C chemical shifts (δ) of the diazanaphthalenes has been recorded. From this dependence the pKa values have been determined using the Henderson-Hasselbach equation. The change in 13C chemical shifts under the influence of nitrogen protonation (Δδ) has been predicted using the Δδ values of quinoline and isoquinoline. The correlation between observed and expected Δδ values of the symmetric diazanaphthalenes is very good. Assuming these changes in chemical shifts to be of general validity, the site of protonation in the asymmetric diazanaphthalenes has been determined by comparison of the expected Δδ values for α- and ß-nitrogen protonation with the observed ones. The site of protonation for 1,6- and 1,7-naphthyridine is the ß-nitrogen atom, whereas for cinnoline both monoprotonated species are present in a significant amount
Exploring droplet impact near a millimetre-sized hole: comparing a closed pit with an open-ended pore
We investigate drop impact dynamics near both closed pits and open- ended
pores experimentally. The resulting impact phenomena differ greatly for a pit
or a pore. For the first, we observe three phenomena: a splash, a jet and an
air bubble, whose appearance depends on the distance between impact location
and pit. Furthermore, we found that splash velocities can reach up to seven
times the impact velocity. Drop impact near a pore, however, results solely in
splashing. Surprisingly, two distinct and disconnected splashing regimes occur,
with a region of plain spreading in-between. For pores, splashes are less
pronounced than in the pit case. We state that, for the pit case, the presence
of air inside the pit plays a crucial role: it promotes splashing and allows
for air bubbles to appear.Comment: 17 pages, 11 figures, 1 supplementary movie, submitted to JF
La traducción de los órganos jurisdiccionales y del personal judicial de España y Alemania
El presente Trabajo de Fin de Grado tiene por objeto analizar detenidamente la problemática existente a la hora de traducir la denominación de los órganos jurisdiccionales y del personal judicial de los ordenamientos jurídicos de España y Alemania. Explicaremos los conceptos más relevantes de ambas jurisdicciones, con el fin de establecer el contexto jurídico de estos términos que con tanta frecuencia aparecen en textos jurídicos, tales como sentencias o autos. Analizaremos, asimismo, las tres técnicas que se pueden llevar a cabo a la hora de traducir estos referentes culturales: la traducción descriptiva, la traducción por equivalencia funcional —o «domesticación»—, y la conservación de la denominación oficial en la lengua origen (LO) explicada en una nota al pie. Ninguna de estas tres corrientes es más aconsejable que las otras; el traductor deberá decantarse por una u otra en función del encargo de traducción y del lector meta
Dramatic effect of fluid chemistry on cornstarch suspensions: linking particle interactions to macroscopic rheology
Suspensions of cornstarch in water exhibit strong dynamic shear-thickening.
We show that partly replacing water by ethanol strongly alters the suspension
rheology. We perform steady and non-steady rheology measurements combined with
atomic force microscopy to investigate the role of fluid chemistry on the
macroscopic rheology of the suspensions and its link with the interactions
between cornstarch grains. Upon increasing the ethanol content, the suspension
goes through a yield-stress fluid state and ultimately becomes a shear-thinning
fluid. On the cornstarch grain scale, atomic force microscopy measurements
reveal the presence of polymers on the cornstarch surface, which exhibit a
co-solvency effect. At intermediate ethanol content, a maximum of polymer
solubility induces high microscopic adhesion which we relate to the macroscopic
yield stress
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