471 research outputs found
Assessing the rider's seat and horse's behavior: difficulties and perspectives
correct seat and position are the basis for a good performance in horseback riding. This study aimed to measure deviations from the correct seat, test a seat improvement program (dismounted exercises), and investigate whether horse behavior was affected by the rider's seat. Five experienced trainers defined 16 seat deviations and scored the occurrence in 20 riders in a dressage test. Half the riders then carried out an individual training program; after 9 weeks, riders were again scored. The study took no video or heart-rate recordings of horses and riders. Panel members did not agree on the deviations in the rider's seat; the study detected no differencesÂżwith the exception of improvement of backward-tilted pelvisÂżbetween the groups. Horse behavior, classified as Âżevasive,Âż increased; horse heart rate decreased in the experimental group. Heart rates of riders in both groups decreased. Seven of 9 riders in the experimental group had the impression that the exercises improved their riding performance. There is a clear need to develop a robust system that allows trainers to objectively evaluate the rider's sea
Banking system stability: A cross-atlantic perspective
Paper prepared for the NBER project on âRisks of Financial Institutionsâ. We benefited from suggestions
and criticism by many participants in the NBER project on âRisks of financial institutionsâ, in particular by
the organizers Mark Carey (also involving Dean Amel and Allen Berger) and Rene Stulz, by our discussant
Tony Saunders and by Patrick de Fontnouvelle, Gary Gorton, Andy Lo, Jim OâBrien and Eric Rosengren.
Furthermore, we are grateful for comments we received at the 2004 European Finance Association Meetings
in Maastricht, in particular by our discussant Marco da Rin and by Christian Upper, at the 2004 Ottobeuren
seminar in economics, notably the thoughts of our discussant Ernst Baltensberger, of Friedrich Heinemann
and of Gerhard Illing, as well as at seminars of the Max Planck Institute for Research on Collective Goods,
the Federal Reserve Bank of St. Louis, the ECB and the University of Frankfurt. Gabe de Bondt and David
Marques Ibanez supported us enormously in finding yield spread data, Lieven Baele and Richard Stehle
kindly made us aware of pitfalls in Datastream equity data. Very helpful research assistance by Sandrine
Corvoisier, Peter Galos and Marco Lo Duca as well as editorial support by Sabine Wiedemann are gratefully
acknowledged. Any views expressed only reflect those of the authors and should not be interpreted as the
ones of the ECB or the Eurosystem. The views expressed herein are those of the author(s) and do not
necessarily reflect the views of the National Bureau of Economic Research.
This paper derives indicators of the severity and structure of banking system risk from asymptotic
interdependencies between banksâ equity prices. We use new tools available from multivariate
extreme value theory to estimate individual banksâ exposure to each other (âcontagion riskâ) and to
systematic risk. Moreover, by applying structural break tests to those measures we study whether
capital markets indicate changes in the importance of systemic risk over time. Using data for the
United States and the euro area, we can also compare banking system stability between the two
largest economies in the world. Finally, for Europe we assess the relative importance of cross-border
bank spillovers as compared to domestic bank spillovers. The results suggest, inter alia, that systemic
risk in the US is higher than in the euro area, mainly as cross-border risks are still relatively mild in
Europe. On both sides of the Atlantic systemic risk has increased during the 1990s
Fundamentals and joint currency crises
It is by now well known that Ănancial returns exhibit heavy tails and
are thus nonnormally distributed. This implies that extreme market
conditions tend to happen more frequently than expected on the basis
of the normal distribution, which is used so often in standard asset pricing approaches. From the point of view of international Ănan-
cial stability and portfolio diversiĂcation, the strength of asset linkages
during crisis periods matters even more, as the linkages determine the
stability of the system as a whole. Several papers talk about increased
correlation between Ănancial assets or markets during crisis periods. As
has been argued before, the use of correlation analysis is not without
problems though. Since the correlation concept is just an intermediary
step in calculating probabilities, we prefer to deĂne market linkages in
terms of conditional probabilities and the expected number of market
crashes
Report of the working group on the measurement of triple gauge boson couplings
The working group discussed several aspects of triple gauge coupling analysis viewed in the light of experiences with the first high energy data recorded at energies above the W pair threshold. Some analysis methods were reviewed briefly, and consideration given to better ways of characterising the data. The measurement of CP violating parameters was discussed. Results were prepared to further quantify the precision attainable on anaomalous couplings in the four-quark channel using jet-charge methods, and finally the trade off between maximum LEP energy-vs-luminosity was quantified.The working group discussed several aspects of triple gauge coupling analysis viewed in the light of experiences with the first high energy data recorded at energies above the W pair threshold. Some analysis methods were reviewed briefly, and consideration given to better ways of characterising the data. The measurement of CP violating parameters was discussed. Results were prepared to further quantify the precision attainable on anaomalous couplings in the four-quark channel using jet-charge methods, and finally the trade off between maximum LEP energy-vs-luminosity was quantified
Kinetic model of II-VI(001) semiconductor surfaces: Growth rates in atomic layer epitaxy
We present a zinc-blende lattice gas model of II-VI(001) surfaces, which is
investigated by means of Kinetic Monte Carlo (KMC) simulations. Anisotropic
effective interactions between surface metal atoms allow for the description
of, e.g., the sublimation of CdTe(001), including the reconstruction of
Cd-terminated surfaces and its dependence on the substrate temperature T. Our
model also includes Te-dimerization and the potential presence of excess Te in
a reservoir of weakly bound atoms at the surface. We study the self-regulation
of atomic layer epitaxy (ALE) and demonstrate how the interplay of the
reservoir occupation with the surface kinetics results in two different
regimes: at high T the growth rate is limited to 0.5 layers per ALE cycle,
whereas at low enough T each cycle adds a complete layer of CdTe. The
transition between the two regimes occurs at a characteristic temperature and
its dependence on external parameters is studied. Comparing the temperature
dependence of the ALE growth rate in our model with experimental results for
CdTe we find qualitative agreement.Comment: 9 pages (REVTeX), 8 figures (EPS). Content revised, references added,
typos correcte
Adsorption of microplastics to the edible Fucus vesiculosus and possible wash off before food application
Exact/heuristic hybrids using rVNS and hyperheuristics for workforce scheduling
In this paper we study a complex real-world workforce scheduling
problem. We propose a method of splitting the problem into smaller parts and
solving each part using exhaustive search. These smaller parts comprise a
combination of choosing a method to select a task to be scheduled and a method
to allocate resources, including time, to the selected task. We use reduced
Variable Neighbourhood Search (rVNS) and hyperheuristic approaches to
decide which sub problems to tackle. The resulting methods are compared to
local search and Genetic Algorithm approaches. Parallelisation is used to
perform nearly one CPU-year of experiments. The results show that the new
methods can produce results fitter than the Genetic Algorithm in less time and
that they are far superior to any of their component techniques. The method
used to split up the problem is generalisable and could be applied to a wide
range of optimisation problems
Magnetized Particle Capture Cross Section for Braneworld Black Hole
Capture cross section of magnetized particle (with nonzero magnetic moment)
by braneworld black hole in uniform magnetic field is considered. The magnetic
moment of particle was chosen as it was done by \citet{rs99} and for the
simplicity particle with zero electric charge is chosen. It is shown that the
spin of particle as well as the brane parameter are to sustain the stability of
particles circularly orbiting around the black hole in braneworld i.e. spin of
particles and brane parameter try to prevent the capture by black hole.Comment: 7 pages, 4 figures, Accepted for publication in Astrophysics & Space
Scienc
Active Galactic Nuclei at the Crossroads of Astrophysics
Over the last five decades, AGN studies have produced a number of spectacular
examples of synergies and multifaceted approaches in astrophysics. The field of
AGN research now spans the entire spectral range and covers more than twelve
orders of magnitude in the spatial and temporal domains. The next generation of
astrophysical facilities will open up new possibilities for AGN studies,
especially in the areas of high-resolution and high-fidelity imaging and
spectroscopy of nuclear regions in the X-ray, optical, and radio bands. These
studies will address in detail a number of critical issues in AGN research such
as processes in the immediate vicinity of supermassive black holes, physical
conditions of broad-line and narrow-line regions, formation and evolution of
accretion disks and relativistic outflows, and the connection between nuclear
activity and galaxy evolution.Comment: 16 pages, 5 figures; review contribution; "Exploring the Cosmic
Frontier: Astrophysical Instruments for the 21st Century", ESO Astrophysical
Symposia Serie
Accretion, Outflows, and Winds of Magnetized Stars
Many types of stars have strong magnetic fields that can dynamically
influence the flow of circumstellar matter. In stars with accretion disks, the
stellar magnetic field can truncate the inner disk and determine the paths that
matter can take to flow onto the star. These paths are different in stars with
different magnetospheres and periods of rotation. External field lines of the
magnetosphere may inflate and produce favorable conditions for outflows from
the disk-magnetosphere boundary. Outflows can be particularly strong in the
propeller regime, wherein a star rotates more rapidly than the inner disk.
Outflows may also form at the disk-magnetosphere boundary of slowly rotating
stars, if the magnetosphere is compressed by the accreting matter. In isolated,
strongly magnetized stars, the magnetic field can influence formation and/or
propagation of stellar wind outflows. Winds from low-mass, solar-type stars may
be either thermally or magnetically driven, while winds from massive, luminous
O and B type stars are radiatively driven. In all of these cases, the magnetic
field influences matter flow from the stars and determines many observational
properties. In this chapter we review recent studies of accretion, outflows,
and winds of magnetized stars with a focus on three main topics: (1) accretion
onto magnetized stars; (2) outflows from the disk-magnetosphere boundary; and
(3) winds from isolated massive magnetized stars. We show results obtained from
global magnetohydrodynamic simulations and, in a number of cases compare global
simulations with observations.Comment: 60 pages, 44 figure
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