1,184 research outputs found
On the shape of vortices for a rotating Bose Einstein condensate
For a Bose-Einstein condensate placed in a rotating trap, we study the
simplified energy of a vortex line derived in Aftalion-Riviere Phys. Rev. A 64,
043611 (2001) in order to determine the shape of the vortex line according to
the rotational velocity and the elongation of the condensate. The energy
reflects the competition between the length of the vortex which needs to be
minimized taking into account the anisotropy of the trap and the rotation term
which pushes the vortex along the z axis. We prove that if the condensate has
the shape of a pancake, the vortex stays straight along the z axis while in the
case of a cigar, the vortex is bent
TCT-395 Dedicated coronary bifurcation stent BiOSS in patients with diabetes. Does the design matter?
Understanding Post-Adoptive Usage Behaviors: A Two-Dimensional View
Recent information systems (IS) publications reveal an emerging interest in studying postadoptive system use behaviors. Compared to the well-established research stream of IS adoption and initial usage, understanding of IS use behaviors after initial implementation stage is still at its early stage. To further develop knowledge about this phenomenon, this study reviews the IS implementation stage model and a variety of post-adoptive usage concepts in extant literature. These usage concepts are classified into three types and are mapped against their corresponding implementation stages. A two dimensional view of these use concepts is then proposed as an alternative perspective to understand these post-adoptive behaviors. Implications are also discussed at the end of this paper
Steering smog prediction
The use of computational steering for smog prediction is described. This application is representative for many underlying issues found in steering high performance applications: high computing times, large data sets, and many different input parameters. After a short description of the smog prediction model, its visualization and steering are described. The amount of computation needed to solve the governing transport equations is alarmingly high. The user has a large number of options for the display of various aspects of the simulation, and also for the interactive control of its input data. Smooth animation is very important to monitor the evolution of pollutants and for a responsive feedback to parameter changes. Here a performance of least 15 frames per second is required. We discuss techniques that allow the user to steer the numerical solver, such that an optimal tradeoff between computation speed and accuracy can be made
For Yield Test Weight Disease Resistance: Settler Oat
\u27Settler,\u27 a new spring oat, was released by the South Dakota Agricultural Experiment Station in 1989 during South Dakota\u27s Centennial celebration and named in honor of the pioneers that settled in South Dakota. Settler exhibits a significant improvement over other varieties released by Reeves in its tolerance to barley yellow dwarf (BYD) virus. This disease is caused by a virus transmitted by insects and is commonly called red leaf
CSE: a modular architecture for computational steering
Computational steering is the ultimate goal of interactive simulation. Steering enables users to supervise and dynamically control the computation of an ongoing simulation. We describe CSE: a modular architecture for a computational steering environment. The kernel of the architecture is designed to be very simple, flexible and minimalistic. All higher level system functionality is pushed into modular components outside of the kernel, resulting in a rich and powerful environment. For these modular components (called satellites) a uniform user interface metaphor for users, based on a tray of cards, has been used. The card tray metaphor is very simple to understand and provides users with a simple mechanism to organize and retrieve the tools. Several applications of the environment are shown
Preventing adolescentsâ externalizing and internalizing symptoms : effects of the Penn Resiliency Program
This study reports secondary outcome analyses from a past study of the Penn Resiliency
Program (PRP), a cognitive-behavioral depression prevention program for middle-school
aged children. Middle school students (N = 697) were randomly assigned to PRP, PEP
(an alternate intervention), or control conditions. Gillham et al., (2007) reported analyses
examining PRPâs effects on average and clinical levels of depression symptoms. We
examine PRPâs effects on parent-, teacher-, and self-reports of adolescentsâ externalizing
and broader internalizing (depression/anxiety, somatic complaints, and social
withdrawal) symptoms over three years of follow-up. Relative to no intervention control,
PRP reduced parent-reports of adolescentsâ internalizing symptoms beginning at the first
assessment after the intervention and persisting for most of the follow-up assessments.
PRP also reduced parent-reported conduct problems relative to no-intervention. There
was no evidence that the PRP program produced an effect on teacher- or self-report of
adolescentsâ symptoms. Overall, PRP did not reduce symptoms relative to the alternate
intervention, although there is a suggestion of a delayed effect for conduct problems.
These findings are discussed with attention to developmental trajectories and the
importance of interventions that address common risk factors for diverse forms of
negative outcomes.peer-reviewe
Faster scannerless GLR parsing
Analysis and renovation of large software portfolios requires syntax analysis of multiple, usually embedded, languages and this is beyond the capabilities of many standard parsing techniques. The traditional separation between lexer and parser falls short due to the limitations of tokenization based on regular expressions when handling multiple lexical grammars. In such cases scannerless parsing provides a viable solution. It uses the power of context-free grammars to be able to deal with a wide variety of issues in parsing lexical syntax. However, it comes at the price of less efficiency. The structure of tokens is obtained using a more powerful but more time and memory intensive parsing algorithm. Scannerless grammars are also more non-deterministic than their tokenized counterparts, increasing the burden on the parsing algorithm even further. In this paper we investigate the application of the Right-Nulled Generalized LR parsing algorithm (RNGLR) to scannerless parsing. We adapt the Scannerless Generalized LR parsing and filtering algorithm (SGLR) to implement the optimizations of RNGLR. We present an updated parsing and filtering algorithm, called SRNGLR, and analyze its performance in comparison to SGLR on ambiguous grammars for the programming languages C, Java, Python, SASL, and C++. Measurements show that SRNGLR is on average 33% faster than SGLR, but is 95% faster on the highly ambiguous SASL grammar. For the mainstream languages C, C++, Java and Python the average speedup is 16%
Computational steering
The traditional cycle in simulation is to prepare input, execute a simulation, and to visualize the results as a post-processing step. However, more insight and a higher productivity can be achieved if these activities are done simultaneously. This is the underlying idea of Computational Steering: researchers change parameters of their simulation on the fly and immediately receive feedback on the effect. In this paper the Computational Steering Environment, CSE, developed at CWI is described. We discuss the requirements of computational steering environment, its relation with high performance computing and networking, and show an application of its use
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