8,298 research outputs found
Feshbach spectroscopy of an ultracold Rb-Cs mixture
Full text linkThis thesis reports the observation of interspecies Feshbach resonances in an ultracold mixture of Rb and Cs atoms. A versatile combined magnetic and optical potential has been designed and constructed which is capable of bringing both and to degeneracy, and reaching high phase-space density in . High phase-space density mixtures are the first step required in the production of ultracold polar molecules, the topic of much current research.
The apparatus capitalises on the efficient capture of atoms by a magnetic trap from a magneto-optical trap, and the efficient sympathetic cooling of Cs by Rb therein. Upon transfer to the crossed optical dipole trap condensates in excess of atoms and approximately atoms are produced after direct evaporation and gravito-magnetic tilting of the potential. The observation of six interspecies - Feshbach resonances are reported, three of which had only been predicted theoretically, allowing testing and development of the theoretical model. Furthermore, the extrapolation of this model has predicted numerous Feshbach resonances between and , none of which have been experimentally observed prior to this work. The versatile nature of this apparatus is discussed, including the application of the current system to cooling of . Initial experiments observed seven interspecies resonances, including a broad s-wave resonance at a magnetic field of G which is in excellent agreement with the theoretical prediction. Further work has revealed that fourteen Feshbach resonances exist in the 0-700 G magnetic field range between and atoms in the and states, respectively. Several of these resonances would be ideal for magneto-association of RbCs molecules, prior to transfer to the rovibrational ground-state
Reminiscence of John Muir by Melville B. Anderson
No full textTHE CONVERSATION OF JOHN MUIR By Melville B. Anderson Professor of English Literature, Leland Stanford University JOHN MUIR is beyond care for what we do…https://scholarlycommons.pacific.edu/cs-jmr/1002/thumbnail.jp
CS2023: ACM/IEEE-CS/AAAI Computer Science Curricula: Knowledge Area Operating Systems
No full textOperating system is the collection of services needed to safely interface the hardware with applications. Core topics focus on the mechanisms and policies needed to virtualize computation, memory, and I/O. Overarching themes that are reused at many levels in computer systems are well illustrated in operating Systems (e.g. polling vs interrupts, caching, flexibility costs overhead, similar scheduling approaches to processes, page replacement, etc.).
OS should focus on how those concepts apply in other areas of CS - trust boundaries, concurrency, persistence, safe extensibility
On large-scale diagonalization techniques for the Anderson model of localization
Full text linkWe propose efficient preconditioning algorithms for an eigenvalue problem arising in quantum physics, namely the computation of a few interior eigenvalues and their associated eigenvectors for large-scale sparse real and symmetric indefinite matrices of the Anderson model
of localization. We compare the Lanczos algorithm in the 1987 implementation by Cullum and Willoughby with the shift-and-invert techniques in the implicitly restarted Lanczos method and in the Jacobi–Davidson method. Our preconditioning approaches for the shift-and-invert symmetric indefinite linear system are based on maximum weighted matchings and algebraic multilevel incomplete
LDLT factorizations. These techniques can be seen as a complement to the alternative idea of using more complete pivoting techniques for the highly ill-conditioned symmetric indefinite Anderson matrices. We demonstrate the effectiveness and the numerical accuracy of these algorithms. Our numerical examples reveal that recent algebraic multilevel preconditioning solvers can accelerate the computation of a large-scale eigenvalue problem corresponding to the Anderson model of localization
by several orders of magnitude
Better outcomes for hospitalized patients with TIA when in stroke units: An observational study, Author Response (Editorial)
No full textEditors' Note: Drs. Phan and Srikanth point out that in “Better outcomes for hospitalized patients with TIA when in stroke units: An observational study,” the recurrence rate was much higher than that in an Australian rapid/outpatient-based TIA pathway. Inability to walk (which could indicate stroke instead of TIA), low usage of antiplatelet therapy, and time to antiplatelet therapy are possible explanations. In response, Cadilhac et al. comment that initiation of aspirin within several hours vs 24–48 hours has not been shown to clearly improve outcomes.No Full Tex
PiLa-CS Professional Learning Community - Workshop 2 Resources
No full textDuring the Summer of 2021 and 2022, the Participating in Literacies and Computer Science (PiLa-CS) Research Practice Partnership convened and supported a community of practice to learn more about how to enable better CS teaching for emergent bilinguals. These are materials from Workshop 2 of the PLC.Sponsored by the National Science Foundation under NSF grant CNS-1738645 and DRL-1837446. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation
Translanguaging Pedagogy in CS Ed
No full textEpisode 3: Translanguaging pedagogy in CS Education
This video looks at how multilingual students already use translanguaging in their computer science classes and discusses how CS educators can further support them with translanguaging pedagogy, a framework that prompts teachers to consider their stance, design, and shifts.
Featuring team members from Participating in Literacies and Computer Science (PiLa-CS), https://www.pila-cs.orgEpisode 3: Translanguaging pedagogy in CS Education
This video looks at how multilingual students already use translanguaging in their computer science classes and discusses how CS educators can further support them with translanguaging pedagogy, a framework that prompts teachers to consider their stance, design, and shifts.
Featuring team members from Participating in Literacies and Computer Science (PiLa-CS), https://www.pila-cs.orgSponsored by the National Science Foundation under NSF grant CNS-1738645 and DRL-1837446. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation
PiLa-CS Professional Learning Community - Design Journal Template
No full textDuring the Summer of 2021 and 2022, the Participating in Literacies and Computer Science (PiLa-CS) Research Practice Partnership convened and supported a community of practice to learn more about how to enable better CS teaching for emergent bilinguals. These are materials from from the PLC for a Design Journal to act as a planing template for teachers.Sponsored by the National Science Foundation under NSF grant CNS-1738645 and DRL-1837446. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation
Code-switching and Coordination in Interpreter-mediated Interaction
No full textThis chapter describes and compares code-switching (CS) by lay participants and institutional representatives in data involving English-speaking migrants from West Africa (Nigeria, Ghana) collected in legal and healthcare settings in Northern Italy. In both settings CS by foreign end-users is found to be relatively common in sequentially ‘reactive’ positions; with the exception of nonce borrowings, lay participants take the initiative in CS more rarely, mainly when pressing personal concerns are at issue. CS by institutional representatives shows a functional sensitivity both to broad institutional aims and to the specific sub-aims of the various phases of the encounter; its greater prevalence in the healthcare setting can, it is argued, be traced to the need to create a collaborative relationship in order to successfully diagnose and treat the patient. Implications of the results for theories of mediated interaction and for the training of community interpreters and court interpreters dealing with migrant populations are discussed
Prediction of the Caspian Sea level using ECMWF seasonal forecasts and reanalysis
Full text linkThis 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
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