5,719 research outputs found
Fast gates for ion traps by splitting laser pulses
We present a fast phase gate scheme that is experimentally achievable and has an operation time more than two orders of magnitude faster than current experimental schemes for low numbers of pulses. The gate time improves with the number of pulses following an inverse power law. Unlike
implemented schemes which excite precise motional sidebands, thus limiting
the gate timescale, our scheme excites multiple motional states using discrete
ultra-fast pulses.We use beam-splitters to divide pulses into smaller components
to overcome limitations due to the finite laser pulse repetition rate. This provides
gate times faster than proposed theoretical schemes when we optimize a practical
setup
Perspects in astrophysical databases
Astrophysics has become a domain extremely rich of scientific data. Data
mining tools are needed for information extraction from such large datasets.
This asks for an approach to data management emphasizing the efficiency and
simplicity of data access; efficiency is obtained using multidimensional access
methods and simplicity is achieved by properly handling metadata. Moreover,
clustering and classification techniques on large datasets pose additional
requirements in terms of computation and memory scalability and
interpretability of results. In this study we review some possible solutions
The MG Rover closure and policy response: an evaluation of the Task Force model in the UK
In recent years there have been a number of high-profile plant closures in the UK. In several cases, the policy response has included setting up a task force to deal with the impacts of the closure. It can be hypothesised that task force involving multi-level working across territorial boundaries and tiers of government is crucial to devising a policy response tailored to people's needs and to ensuring success in dealing with the immediate impacts of a closure. This suggests that leadership, and vision, partnership working and community engagement, and delivery of high quality services are important. This paper looks at the case of the MG Rover closure in 2005, to examine the extent to which the policy response to the closure at the national, regional and local levels dealt effectively with the immediate impacts of the closure, and the lessons that can be learned from the experience. Such lessons are of particular relevance given the closure of the LDV van plant in Birmingham in 2009 and more broadly – such as in the case of the downsizing of the Opel operation in Europe following its takeover by Magna
Plant closures and taskforce responses:an analysis of the impact of and policy response to MG Rover in Birmingham
This paper explores the socio-economic impacts and associated policy responses to the collapse of MG Rover at Longbridge in Birmingham. Critically, it attempts to move beyond a ‘standard’ taskforce narrative that emphasizes the role of the regional response. While recognizing that significant policy ‘successes’ were indeed evident at the regional level in anticipating and responding to the crisis, a wider perspective is required that situates this taskforce response in (1) a fuller understanding of labour market precariousness (that in turn mitigates some of its policy ‘successes’), and (2) more local perspectives that highlight the local impacts of closure, the role of the neighbourhood level officials and the third sector in mediating these. Taking this broader perspective suggests that longer-term, workers face a precarious situation and the need for policies to create and sustain ‘good quality’ jobs remains paramount. Adding in more local perspectives, a key lesson from the Longbridge experience for dealing with closures more generally is that the public policy responses must be: multidimensional in that they transcend narrow sector-based concerns and addresses broader spatial impacts; inclusive in that they build on a broad coalition of economic and social stakeholders; and long-term in that they acknowledge that adaptation takes many years. If anything, the Birmingham Longbridge experience demonstrates the difficulty of achieving such responses in the context of crisis where action is imperative and deliberation a luxury
A morphological algorithm for improving radio-frequency interference detection
A technique is described that is used to improve the detection of
radio-frequency interference in astronomical radio observatories. It is applied
on a two-dimensional interference mask after regular detection in the
time-frequency domain with existing techniques. The scale-invariant rank (SIR)
operator is defined, which is a one-dimensional mathematical morphology
technique that can be used to find adjacent intervals in the time or frequency
domain that are likely to be affected by RFI. The technique might also be
applicable in other areas in which morphological scale-invariant behaviour is
desired, such as source detection. A new algorithm is described, that is shown
to perform quite well, has linear time complexity and is fast enough to be
applied in modern high resolution observatories. It is used in the default
pipeline of the LOFAR observatory.Comment: Accepted for publication in A&
Pain expressiveness and altruistic behavior: an exploration using agent-based modeling
Predictions which invoke evolutionary mechanisms are hard to test. Agent-based modeling in artificial life offers a way to simulate behaviors and interactions in specific physical or social environments over many generations. The outcomes have implications for understanding adaptive value of behaviors in context. Pain-related behavior in animals is communicated to other animals that might protect or help, or might exploit or predate. An agent-based model simulated the effects of displaying or not displaying pain (expresser/nonexpresser strategies) when injured and of helping, ignoring, or exploiting another in pain (altruistic/nonaltruistic/selfish strategies). Agents modeled in MATLAB interacted at random while foraging (gaining energy); random injury interrupted foraging for a fixed time unless help from an altruistic agent, who paid an energy cost, speeded recovery. Environmental and social conditions also varied, and each model ran for 10,000 iterations. Findings were meaningful in that, in general, contingencies that evident from experimental work with a variety of mammals, over a few interactions, were replicated in the agent-based model after selection pressure over many generations. More energy-demanding expression of pain reduced its frequency in successive generations, and increasing injury frequency resulted in fewer expressers and altruists. Allowing exploitation of injured agents decreased expression of pain to near zero, but altruists remained. Decreasing costs or increasing benefits of helping hardly changed its frequency, whereas increasing interaction rate between injured agents and helpers diminished the benefits to both. Agent-based modeling allows simulation of complex behaviors and environmental pressures over evolutionary time
Orthogonal Range Reporting and Rectangle Stabbing for Fat Rectangles
In this paper we study two geometric data structure problems in the special
case when input objects or queries are fat rectangles. We show that in this
case a significant improvement compared to the general case can be achieved.
We describe data structures that answer two- and three-dimensional orthogonal
range reporting queries in the case when the query range is a \emph{fat}
rectangle. Our two-dimensional data structure uses words and supports
queries in time, where is the number of points in the
data structure, is the size of the universe and is the number of points
in the query range. Our three-dimensional data structure needs
words of space and answers queries in time. We also consider the rectangle stabbing problem on a set of
three-dimensional fat rectangles. Our data structure uses space and
answers stabbing queries in time.Comment: extended version of a WADS'19 pape
Effects of deceptive running speed on physiology, perceptual responses, and performance during sprint-distance triathlon
Objective
This study examined the effects of speed deception on performance, physiological and perceptual responses, and pacing during sprint-distance triathlon running.
Methods
Eight competitive triathletes completed three simulated sprint-distance triathlons (0.75 km swim, 20 km bike, 5 km run) in a randomised order, with swimming and cycling sections replicating baseline triathlon performance. During the first 1.66 km of the run participants maintained an imposed speed, completing the remaining 3.33 km as quickly as possible. Although participants were informed that initially prescribed running speed would reflect baseline performance, this was true during only one trial (Tri-Run100%). As such, other trials were either 3% faster (Tri-Run103%), or 3% slower (Tri-Run97%) than baseline during this initial period.
Results
Performance during Tri-Run103% (1346 ± 108 s) was likely faster than Tri-Run97% (1371 ± 108 s), and possibly faster than Tri-Run100% (1360 ± 125 s), with these differences likely to be competitively meaningful. The first 1.66 km of Tri-Run103% induced greater physiological strain compared to other conditions, whilst perceptual responses were not significantly different between trials.
Conclusions
It appears that even during ‘all-out’ triathlon running, athletes maintain some form of ‘reserve’ capacity which can be accessed by deception. This suggests that expectations and beliefs have a practically meaningful effect on pacing and performance during triathlon, although it is apparent that an individual’s conscious intentions are secondary to the brains sensitivity to potentially harmful levels of physiological and perceptual strain
¿Debemos temer a la inteligencia artificial?: análisis en profundidad
El ISBN corresponde a la versión electrónica del documentoDesde hace ya algunos años, la inteligencia artificial (IA) ha estado cobrando impulso. Una oleada de programas que sacan el máximo rendimiento a los procesadores de última generación están obteniendo resultandos espectaculares. Una de las aplicaciones más destacadas de la IA es el reconocimiento de voz: si bien los primeros modelos eran extraños y se caracterizaban por defectos constantes, ahora son capaces de responder correctamente a todo tipo de solicitudes de los usuarios en las más diversas situaciones. En el ámbito del reconocimiento de imagen también se están logrando avances notables, con programas capaces de reconocer figuras —e incluso gatos— en vídeos en línea que ahora se están adaptando para que el software controle los coches autónomos que invadirán nuestras calles en los próximos años. A día de hoy no podemos imaginar un futuro en Europa sin una IA avanzada que influya cada vez en más facetas de nuestra vida, desde el trabajo a la medicina, y desde la educación a las relaciones interpersonales
From Offshore Operation to Onshore Simulator: Using Visualized Ethnographic Outcomes to Work with Systems Developers
This paper focuses on the process of translating insights from a Computer Supported Cooperative Work (CSCW)-based study, conducted on a vessel at sea, into a model that can assist systems developers working with simulators, which are used by vessel operators for training purposes on land. That is, the empirical study at sea brought about rich insights into cooperation, which is important for systems developers to know about and consider in their designs. In the paper, we establish a model that primarily consists of a ‘computational artifact’. The model is designed to support researchers working with systems developers. Drawing on marine examples, we focus on the translation process and investigate how the model serves to visualize work activities; how it addresses relations between technical and computational artifacts, as well as between functions in technical systems and functionalities in cooperative systems. In turn, we link design back to fieldwork studies
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