9,525 research outputs found
Prediction of the Caspian Sea level using ECMWF seasonal forecasts and reanalysis
This article is made available through the Brunel Open Access Publishing Fund. This article is distributed under the terms of the Creative Commons Attribution License which permits any use, distribution, and
reproduction in any medium, provided the original author(s) and the
source are credited.The hydrological budget of the Caspian Sea (CS) is investigated using the European Centre for Medium-Range Weather Forecasts interim reanalysis (ERAi) and seasonal forecast (FCST) data with the aim of predicting the Caspian Sea Level (CSL) some months ahead. Precipitation and evaporation are used. After precipitation events over the Volga River, the discharge (Volga River discharge (VRD)) follows with delays, which are parameterized. The components of the water budget from ERAi and FCSTs are integrated to obtain time series of the CSL. Observations of the CSL and the VRD are used for comparison and tuning. The quality of ERAi data is sufficiently good to calculate the time variability of the CSL with a satisfactory accuracy. Already the storage of water within the Volga Basin allows forecasts of the CSL a few months ahead, and using the FCSTs of precipitation improves the CSL forecasts. The evaporation in the seasonal forecasts is deficient due to unrealistic sea surface temperatures over the CS. Impacts of different water budget terms on the CSL variability are shown by a variety of validation tools. The importance of precipitation anomalies over the catchment of the Volga River is confirmed, but also impacts from the two southern rivers (Sefidrud and Kura River) and the evaporation over the CS become obvious for some periods. When pushing the FCSTs beyond the limits of the seasonal FCSTs to 1 year, considerable forecast skill can still be found. Validating only FCSTs by the present approach, which show the same trend as one based on a statistical method, significantly enhances the skill scores
Can a spontaneous collapse in flavour oscillations be tested at KLOE?
Why do we never see a table in a superposition of here and there? This
problem gets a solution by so called collapse models assuming the collapse as a
genuinely physical process. Here we consider two specific collapse models and
apply them to systems at high energies, i.e. flavour oscillating neutral meson
systems. We find on one hand a potentially new interpretation of the decay
rates introduced by hand in the standard formalism and on the other hand that
these systems at high energies constrain by experimental data the possible
collapse scenarios.Comment: To appear in the proceedings of the KLOE-2 Workshop on e+e- collision
physics at 1 GeV, 26-28 October 2016, INFN - Laboratori Nazionali di
Frascati, Ital
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From A Service-Learning to A Social-Change Model
Tutor education courses that prepare students to serve as peer
writing consultants often include service learning; a typical servicelearning
tutor education course involves sending students to tutor
in local schools, usually in underserved neighborhoods. Existing
writing center scholarship on service learning tends to overlook the
limitations of this model. This article advances a radically different
approach for tutor education where the course acts as an incubator
for social change on campus. Informed by the principles advanced
by the critical service learning movement, the course described here
invites students to design and implement campus-based community
building projects. Ultimately, this article demonstrates that a course
focused on community building, rather than tutoring theory and
strategies, can effectively prepare students to serve as peer writing
consultants while imparting a heightened awareness of social
inequities and a deep investment in the campus community.University Writing Cente
Primitive ontology and quantum state in the GRW matter density theory
The paper explains in what sense the GRW matter density theory (GRWm) is a
primitive ontology theory of quantum mechanics and why, thus conceived, the
standard objections against the GRW formalism do not apply to GRWm. We consider
the different options for conceiving the quantum state in GRWm and argue that
dispositionalism is the most attractive one.Comment: arXiv admin note: text overlap with arXiv:quant-ph/0603027 by other
author
Models of wave-function collapse, underlying theories, and experimental tests
We describe the state of the art in preparing, manipulating and detecting coherent molecular matter. We focus on experimental methods for handling the quantum motion of compound systems from diatomic molecules to clusters or biomolecules.Molecular quantum optics offers many challenges and innovative prospects: already the combination of two atoms into one molecule takes several well-established methods from atomic physics, such as for instance laser cooling, to their limits. The enormous internal complexity that arises when hundreds or thousands of atoms are bound in a single organic molecule, cluster or nanocrystal provides a richness that can only be tackled by combining methods from atomic physics, chemistry, cluster physics, nanotechnology and the life sciences.We review various molecular beam sources and their suitability for matter-wave experiments. We discuss numerous molecular detection schemes and give an overview over diffraction and interference experiments that have already been performed with molecules or clusters.Applications of de Broglie studies with composite systems range from fundamental tests of physics up to quantum-enhanced metrology in physical chemistry, biophysics and the surface sciences.Nanoparticle quantum optics is a growing field, which will intrigue researchers still for many years to come. This review can, therefore, only be a snapshot of a very dynamical process
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