311 research outputs found
Risk attitude, beliefs, and information in a corruption game: An experimental analysis
For our experiment on corruption we designed a coordination game to model the influence of risk attitudes, beliefs, and information on behavioral choices and determined the equilibria. We observed that the participants' risk attitudes failed to explain their choices between corrupt and non-corrupt behavior. Instead, beliefs appeared to be a better predictor of whether or not they would opt for the corrupt alternative. Furthermore, varying the quantity of information available to players (modeled by changing the degree of uncertainty) provided additional insight into the players' propensity to engage in corrupt behavior. The experimental results show that a higher degree of uncertainty in the informational setting reduces corruption. --Corruption,game theory,experiment,risk attitude,beliefs
Threshold effects in charm hadroproduction.
We describe calculations of cc production to next-to-next-to-leading order (NNLO)
and next-to-next-to-leading logarithm (NNLL) near threshold in pp and −p interactions.
We study the relevance of these calculations for existing cc total cross section data by
examining their sensitivity to partonic threshold kinematics, their convergence properties
and scale dependence
Collapse of Coherent Large Scale Flow in Strongly Turbulent Liquid Metal Convection
The large-scale flow structure and the turbulent transfer of heat and
momentum are directly measured in highly turbulent liquid metal convection
experiments for Rayleigh numbers varied between and and Prandtl numbers of . Our
measurements are performed in two cylindrical samples of aspect ratios diameter/height and 1 filled with the eutectic alloy GaInSn. The
reconstruction of the three-dimensional flow pattern by 17 ultrasound Doppler
velocimetry sensors detecting the velocity profiles along their beamlines in
different planes reveals a clear breakdown of coherence of the large-scale
circulation for . As a consequence, the scaling laws for heat and
momentum transfer inherit a dependence on the aspect ratio. We show that this
breakdown of coherence is accompanied with a reduction of the Reynolds number
. The scaling exponent of the power law
crosses \FIN{eventually} over from to 0.124 when the liquid metal
flow at reaches and the coherent
large-scale flow is completely collapsed.Comment: 4 pages, 5 figures, 1 supplementary with 1 figure and 4 tables, 1
movi
Otto Warburg and his contributions to the screw pine family (Pandanaceae)
Otto Warburg (1859–1938) had a great interest in tropical botany. He travelled in South-East Asia and the South Pacific between 1885 and 1889 and brought back a considerable collection of plant specimens from this expedition later donated to the Royal Botanical Museum in Berlin. Warburg published the first comprehensive monograph on the family Pandanaceae in 1900 in the third issue of Das Pflanzenreich established and edited by Adolf Engler (1844–1930). The aim of this article is to clarify the taxonomy, nomenclature and typification of Warburg's contributions to the Pandanaceae. Considerable parts of Warburg's original material was destroyed in Berlin during World War II but duplicates survived, shared by Engler and Warburg with Ugolino Martelli (1860–1934). Martelli was an expert on the family and he assembled a precious herbarium of Pandanaceae that was later donated to the Museo di Storia Naturale dell'Università degli Studi di Firenze. Warburg published 86 new names in Pandanaceae between 1898 and 1909 (five new sections, 69 new species, five new varieties, two new combinations and five replacement names). A complete review of the material extant in B and FI led to the conclusion that 38 names needed a nomenclatural act: 34 lectotypes, three neotypes and one epitype are designated here. Twenty new synonyms are also proposed. One Freycinetia name and six Pandanus names are considered as incertae sedis. A total of 21 names published by Warburg are accepted: 11 in Freycinetia and ten in Pandanus. In addition, four names published in Pandanus by Warburg serve as the basionyms of accepted names in the genus Benstonea
Oscillatory large-scale circulation in liquid-metal thermal convection and its structural unit
In Rayleigh-B\'enard convection (RBC), the size of a flow domain and its
aspect ratio (a ratio between the spatial length and height of the
domain) affect the shape of the large-scale circulation (LSC). For some aspect
ratios, the flow dynamics include a three-dimensional oscillatory mode known as
a jump-rope vortex (JRV), however, the effects of varying aspect ratios on this
mode are not well investigated. In this paper, we study these aspect-ratio
effects in liquid metals, for a low Prandtl number . Direct numerical
simulations and experiments are carried out for a Rayleigh number range and square cuboid domains with
, , and . Our study demonstrates that a repeating
pattern of a JRV encountered at an aspect ratio is the
basic structural unit that builds up to a lattice of interlaced JRVs at the
largest aspect ratio. The size of the domain determines how many structural
units are self-organized within the domain; the number of the realized units is
expected to scale as with sufficiently large and growing
. We find the oscillatory modes for all investigated ,
however, they are more pronounced for and . Future
studies for large-aspect ratio domains of different shapes would enhance our
understanding of how the JRVs adjust and reorganize at such scaled-up
geometries, and answer the question of whether they are indeed the smallest
superstructure units.Comment: 26 pages, 16 figure
Risk attitude, beliefs, and information in a corruption game - An experimental analysis
For our experiment on corruption we designed a coordination game to model the influence of risk attitudes, beliefs, and information on behavioral choices and determined the equilibria. We observed that the participants' risk attitudes failed to explain their choices between corrupt and non-corrupt behavior. Instead, beliefs appeared to be a better predictor of whether or not they would opt for the corrupt alternative. Furthermore, varying the quantity of information available to players (modeled by changing the degree of uncertainty) provided additional insight into the players' propensity to engage in corrupt behavior. The experimental results show that a higher degree of uncertainty in the informational setting reduces corruption
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