Network Synchronization in a Noisy Environment with Time Delays: Fundamental Limits and Trade-Offs

We study the effects of nonzero time delays in stochastic synchronization problems with linear couplings in an arbitrary network. Using the known exact threshold value from the theory of differential equations with delays, we provide the synchronizability threshold for an arbitrary network. Further, by constructing the scaling theory of the underlying fluctuations, we establish the absolute limit of synchronization efficiency in a noisy environment with uniform time delays, i.e., the minimum attainable value of the width of the synchronization landscape. Our results have also strong implications for optimization and trade-offs in network synchronization with delays.Comment: 3 figure

The Impact of Competing Time Delays in Coupled Stochastic Systems

We study the impact of competing time delays in coupled stochastic synchronization and coordination problems. We consider two types of delays: transmission delays between interacting elements and processing, cognitive, or execution delays at each element. We establish the scaling theory for the phase boundary of synchronization and for the steady-state fluctuations in the synchronizable regime. Further, we provide the asymptotic behavior near the boundary of the synchronizable regime. Our results also imply the potential for optimization and trade-offs in synchronization problems with time delays

Arithmetic on a Distributed-Memory Quantum Multicomputer

We evaluate the performance of quantum arithmetic algorithms run on a distributed quantum computer (a quantum multicomputer). We vary the node capacity and I/O capabilities, and the network topology. The tradeoff of choosing between gates executed remotely, through ``teleported gates'' on entangled pairs of qubits (telegate), versus exchanging the relevant qubits via quantum teleportation, then executing the algorithm using local gates (teledata), is examined. We show that the teledata approach performs better, and that carry-ripple adders perform well when the teleportation block is decomposed so that the key quantum operations can be parallelized. A node size of only a few logical qubits performs adequately provided that the nodes have two transceiver qubits. A linear network topology performs acceptably for a broad range of system sizes and performance parameters. We therefore recommend pursuing small, high-I/O bandwidth nodes and a simple network. Such a machine will run Shor's algorithm for factoring large numbers efficiently.Comment: 24 pages, 10 figures, ACM transactions format. Extended version of Int. Symp. on Comp. Architecture (ISCA) paper; v2, correct one circuit error, numerous small changes for clarity, add reference

Angular distribution of positrons emitted from metal surfaces

The effect of inelastic scattering processes on the angular distribution of positrons spontaneously emitted from metal surfaces is investigated. Angular and energy spectra are calculated for positrons suffering energy loss due to electron-hole excitation in emission from materials with low (aluminum) and high (tungsten) positron work functions.Peer reviewe

The tensor part of the Skyrme energy density functional. III. Time-odd terms at high spin

This article extends previous studies on the effect of tensor terms in the Skyrme energy density functional by breaking of time-reversal invariance. We have systematically probed the impact of tensor terms on properties of superdeformed rotational bands calculated within the cranked Hartree-Fock-Bogoliubov approach for different parameterizations covering a wide range of values for the isoscalar and isovector tensor coupling constants. We analyze in detail the contribution of the tensor terms to the energies and dynamical moments of inertia and study their impact on quasi-particle spectra. Special attention is devoted to the time-odd tensor terms, the effect of variations of their coupling constants and finite-size instabilities.Comment: 28 pages, 34 figure

PHP8 ADVERSE DRUG REACTIONS IN GERMANY: COST ANALYSIS OF INTERNAL MEDICINE HOSPITALIZATIONS

La irrupción de las nuevas tecnologías en la vida cotidiana ha supuesto una enorme revolución a la hora de determinar tanto las relaciones entre los sujetos como de comprender e interpretar la realidad. Por ello, la alfabetización mediática se plantea hoy como una disciplina indispensable en los sistemas educativos de todo el mundo. Este artículo recoge los resultados obtenidos en un experimento con estudiantes de educación secundaria. El objetivo es observar hasta qué punto la alfabetización mediática puede resultar de utilidad a la hora de potenciar las competencias interpretativas de los estudiantes. La muestra está formada por alumnos de 14-15 años, pertenecientes al curso Décimo de tres centros escolares de Guayaquil. La variable independiente es conformada por cinco spots. Los resultados subrayan que, al margen del contexto socioeconómico, los alumnos instruidos mediáticamente muestran una capacidad interpretativa y decodificadora superior a aquellos otros que no lo fueron.  &nbsp