Semiclassical approach to fidelity amplitude

The fidelity amplitude is a quantity of paramount importance in echo type experiments. We use semiclassical theory to study the average fidelity amplitude for quantum chaotic systems under external perturbation. We explain analytically two extreme cases: the random dynamics limit --attained approximately by strongly chaotic systems-- and the random perturbation limit, which shows a Lyapunov decay. Numerical simulations help us bridge the gap between both extreme cases.Comment: 10 pages, 9 figures. Version closest to published versio

UN MODELO CAUSAL DE COMPETITIVIDAD EMPRESARIAL PLANTEADO DESDE LA VBR: CAPACIDADES DIRECTIVAS, DE INNOVACIÓN, MARKETING Y CALIDAD

El propósito de esta investigación es desarrollar un modelo explicativo de la competitividad empresarial a partir de factores internos a la empresa. Para ello se identifican los factores de competitividad más importantes en el caso de las empresas manufactureras vascas, así como las variables que permiten caracterizarlos, utilizando técnicas cualitativas basadas en entrevistas con directivos. Los factores resultantes son las capacidades directivas, las capacidades de innovación, las capacidades de marketing y las capacidades de calidad. Tras analizar estos factores bajo la Visión de la empresa Basada en Recursos (VBR), y definir sus escalas de medida, se plantea un modelo causal que relaciona cada uno de ellos con la competividad de la empresa. Este modelo otorga una importancia especial a las capacidades directivas al plantear este factor como precedente del resto de capacidades de la empresa. El modelo es contrastado a través de la técnica de modelado con ecuaciones estructurales utilizando una muestra representativa de la población de empresas manufactureras vascas formada por 861 empresas

Análise da divulgação e comercialização do Curadermite: uma tecnologia gerada pela Embrapa Tabuleiros Costeiros.

O estudo mostra que o conhecimento dos produtores e extensionistas acerca dos aspectos diferenciais do Curadermite se restringiu, praticamente, à Bahia e Sergipe, estados de maior proximidade geográfica com a Embrapa Tabuleiros Costeiros, produtora do Curadermite. Por outro lado, o esforço de divulgação da tecnologia não obteve êxito nos meios acadêmico e científico onde o curadermite é praticamente desconhecido. O trabalho tem como resultado um conjunto de indicativos que podem ser utilizados na reorientação da política de divulgação e marketing de tecnologias na Embrapa.bitstream/CPATC/19761/1/bp-28.pd

Genótipos de feijoeiro comum em sistema de produção orgânico.

O objetivo foi identificar linhagens e cultivares de feijoeiro comum desenvolvidas pelo programa de melhoramento genético da Embrapa Arroz Feijão adaptadas ao cultivo em sistema orgânico, em diferentes épocas de semeadura.bitstream/CNPAF/26601/1/comt_141.pd

Noise models for superoperators in the chord representation

We study many-qubit generalizations of quantum noise channels that can be written as an incoherent sum of translations in phase space. Physical description in terms of the spectral properties of the superoperator and the action in phase space are provided. A very natural description of decoherence leading to a preferred basis is achieved with diffusion along a phase space line. The numerical advantages of using the chord representation are illustrated in the case of coarse-graining noise.Comment: 8 pages, 5 .ps figures (RevTeX4). Submitted to Phys. Rev. A. minor changes made, according to referee suggestion

Viscosity measurements of liquid toluene at low temperatures using a dual vibrating-wire technique

A recently developed dual vibrating-wire technique has been used to perform viscosity measurements of liquid toluene in the temperature range 213 K ≤ T ≤ 298 K, and at pressures up to approximately 20 MPa. The results were obtained by operating the vibrating-wire sensor in both forced and free decay modes. The estimated precision of the viscosity measurements, in either mode of operation, is ±0.5%, for temperatures above or equal to 273 K, increasing with decreasing temperature up to ±1% at 213 K. The corresponding overall uncertainty is estimated to be within ±1% and ±1.5%, respectively

Genótipos de feijoeiro comum em sistema de produção orgânico.

O objetivo foi identificar linhagens e cultivares de feijoeiro comum desenvolvidas pelo programa de melhoramento genético da Embrapa Arroz Feijão adaptadas ao cultivo em sistema orgânico, em diferentes locais e épocas de semeadura

Traffic monitoring for assuring quality of advanced services in future internet

The final publication is available at Springer via http://dx.doi.org/10.1007/978-3-642-21560-5_16Services based on packet switched networks are becoming dominant in telecommunication business and both operators and service providers must evolve in order to guarantee the required quality. Increasing bandwidth is no longer a viable solution because of the business erosion for network operators which cannot expect revenues due to the large investments required to satisfy new applications demand of bandwidth. This paper presents devices and a specific architecture of services monitoring platform that allows network operators and service providers to analyze the perceived quality of service and check their service level agreements. Thus, a cost-effective service management, based on direct IP traffic measuring, can be supported on integrated monitoring systems to provide network-centric mechanisms for differentiated quality of service, security and other advanced services.This work has been partially developed in the framework of the Celtic and EUREKA initiative IPNQSIS (IP Network Monitoring for Quality of Service Intelligent Support)