La ética de la confianza en el periodismo digital

Con base en un estudio cualitativo realizado entre 2009-2010 con usuarios de sitios web periodísticos en Bélgica, este artículo propone un análisis ético de la confianza en el periodismo digital articulado alrededor de tres valores morales evocados por los participantes en el estudio: (1) la credibilidad del periodista digital en términos de su responsabilidad moral al verificar las fuentes, (2) la transparencia informativa y financiera de las organizaciones periodísticas digitales y (3) la construcción de redes de confianza entre lectores destinadas a evaluar y promover los sitios periodísticos digitales que ellos consideran dignos de confianza.Based on a qualitative study carried out between 2009-2010 with Belgian users of online news sites, this paper provides an ethical analysis of trust in online journalism built upon three moral values highlighted by participants in the study: (1) Journalists’ credibility as a function of their moral responsibility when doing fact checking, (2) online news sites’ reporting and financial transparency, and (3) building networks of trust among readers aimed at promoting online news sites they consider as trustworth

Tecnología, valores periodísticos: implicaciones de la ética informativa para el periodismo digital

Este artículo analiza algunas de las implicaciones de la ética informática para el periodismo digital. Con base en dos enfoques específicos, a saber, el diseño sensible a los valores y la ética informática reveladora, se argumenta que el diseño de ciertas tecnologías utilizadas en el periodismo digital impone limitaciones en las acciones de los periodistas y lectores y, en consecuencia, afectan a valores morales fundamentales como la privacidad, la autonomía, la justicia y la democracia. Algunas conclusiones relevantes y pistas de investigación futura serán ofrecidas al final del artículo.This paper analyzes some implications of computer ethics for online journalism. By drawing on two specific trends, namely Value Sensitive Design and Disclosive Computer Ethics, it will be argued that the design of some computer technologies in online journalism constrain journalists’ and audiences’ action patterns and, consequently, affect core moral values such as privacy, autonomy, justice and democracy. Some relevant conclusions and prospectives for future research will be provided in the final section

Beyond conventional factorization: Non-Hermitian Hamiltonians with radial oscillator spectrum

The eigenvalue problem of the spherically symmetric oscillator Hamiltonian is revisited in the context of canonical raising and lowering operators. The Hamiltonian is then factorized in terms of two not mutually adjoint factorizing operators which, in turn, give rise to a non-Hermitian radial Hamiltonian. The set of eigenvalues of this new Hamiltonian is exactly the same as the energy spectrum of the radial oscillator and the new square-integrable eigenfunctions are complex Darboux-deformations of the associated Laguerre polynomials.Comment: 13 pages, 7 figure

Velocity Distribution in a Viscous Granular Gas

We investigate the velocity relaxation of a viscous one-dimensional granular gas, that is, one in which neither energy nor momentum is conserved in a collision. Of interest is the distribution of velocities in the gas as it cools, and the time dependence of the relaxation behavior. A Boltzmann equation of instantaneous binary collisions leads to a two-peaked distribution with each peak relaxing to zero velocity as 1/t while each peak also narrows as 1/t. Numerical simulations of grains on a line also lead to a double-peaked distribution that narrows as 1/t. A Maxwell approximation leads to a single-peaked distribution about zero velocity with power-law wings. This distribution narrows exponentially. In either case, the relaxing distribution is not of Maxwell-Boltzmann form

Multi-objective decision model for green supply chain management

In this paper, a multi-objective linear programming model was developed which sought to simultaneously optimize total costs and total GHG emissions for the Thai Rubber supply chain. The model was solved by the ε -constraint method which computed the Pareto optimal solution. Each point in the Pareto set entailed a different design of quantity of rubber product flow between the supply chain entities and transport modes and routes. The result obtained show the trade-offs between costs and GHG emissions. It appears that improvements in cost reductions are only possible by compromising on and allowing for higher GHG emissions. From the Pareto set of solutions, each point is equally effective solution for achieving significant cost reductions without compromising too far on GHG emissions. Scenarios analysis were considered to examine the impact of transportation and distribution restructuring on the trade-off between GHG emissions and costs vis-à-vis the baseline model. Overall, the model developed in this research, together with its Pareto optimal solutions analysis, shows that it can be used as an effective tool to design a new and workable GSCM model for the Thai Rubber industry

Robustness of the European power grids under intentional attack

The power grid defines one of the most important technological networks of our times and sustains our complex society. It has evolved for more than a century into an extremely huge and seemingly robust and well understood system. But it becomes extremely fragile as well, when unexpected, usually minimal, failures turn into unknown dynamical behaviours leading, for example, to sudden and massive blackouts. Here we explore the fragility of the European power grid under the effect of selective node removal. A mean field analysis of fragility against attacks is presented together with the observed patterns. Deviations from the theoretical conditions for network percolation (and fragmentation) under attacks are analysed and correlated with non topological reliability measures.Comment: 7 pages, 4 figure

Pulse propagation in decorated granular chains: An analytical approach

We study pulse propagation in one-dimensional chains of spherical granules decorated with small grains placed between large granules. The effect of the small granules can be captured by replacing the decorated chains by undecorated chains of large granules of appropriately renormalized mass and effective interaction between the large granules. This allows us to obtain simple analytic expressions for the pulse propagation properties using a generalization of the binary collision approximation introduced in our earlier work [Phys. Rev. E in print (2009); Phys. Rev. E {\bf 69}, 037601 (2004)]Comment: 10 pages and 12 figure

Observation of two-wave structure in strongly nonlinear dissipative granular chains

In a strongly nonlinear viscous granular chain under conditions of loading that exclude stationary waves (e.g., impact by a single grain) we observe a pulse that consists of two interconnected but distinct parts. One is a leading narrow "primary pulse" with properties similar to a solitary wave in a "sonic vacuum." It arises from strong nonlinearity and discreteness in the absence of dissipation, but now decays due to viscosity. The other is a broad, much more persistent shock-like "secondary pulse" trailing the primary pulse and caused by viscous dissipation. The medium behind the primary pulse is transformed from a "sonic vacuum" to a medium with finite sound speed. When the rapidly decaying primary pulse dies, the secondary pulse continues to propagate in the "sonic vacuum," with an oscillatory front if the viscosity is relatively small, until its eventual (but very slow) disintegration. Beyond a critical viscosity there is no separation of the two pulses, and the dissipation and nonlinearity dominate the shock-like attenuating pulse which now exhibits a nonoscillatory front

Coherent-State Approach to Two-dimensional Electron Magnetism

We study in this paper the possible occurrence of orbital magnetim for two-dimensional electrons confined by a harmonic potential in various regimes of temperature and magnetic field. Standard coherent state families are used for calculating symbols of various involved observables like thermodynamical potential, magnetic moment, or spatialdistribution of current. Their expressions are given in a closed form and the resulting Berezin-Lieb inequalities provide a straightforward way to study magnetism in various limit regimes. In particular, we predict a paramagnetic behaviour in the thermodynamical limit as well as in the quasiclassical limit under a weak field. Eventually, we obtain an exact expression for the magnetic moment which yields a full description of the phase diagram of the magnetization.Comment: 21 pages, 6 figures, submitted to PR