Comment on Real‐Time Observation on Dynamic Growth/Dissolution of Conductive Filaments in Oxide‐Electrolyte‐ Based ReRAM

Filament formation and dissolution in the system Ag(Cu)/ZrO₂/Pt were observed by Liu et al. [Adv. Mater. 2012, 24, 1844]. Their explanation of the phenomena is shown here to be inappropriate. Various situations, including the “bipolar electrode” shown in the figure, are considered and the difference between the behavior in electrochemical metallization memories (ECMs) and valence change memories (VCMs) outlined. Of crucial importance for distinguishing ECM from VCM behavior, that is, the effects of cation and anion migration, is the choice of the solid materials used to transport metal cations. A possible explanation of the phenomena is proposed.     

Assessing the quality of sensory experience for multimedia presentations

This paper introduces the concept of sensory experience by utilizing sensory effects such as wind or lighting as another dimension which contributes to the quality of the user experience. In particular, we utilize a representation format for sensory effects that are attached to traditional multimedia resources such as audio, video, and image contents. Sensory effects (e.g., wind, lighting, explosion, heat, cold) are rendered on special devices (e.g., fans, ambient lights, motion chair, air condition) in synchronization with the traditional multimedia resources and shall stimulate other senses than audition and vision (e.g., mechanoreception, equilibrioception, thermoreception), with the intention to increase the users Quality of Experience (QoE). In particular, the paper provides a comprehensive introduction into the concept of sensory experience, its assessment in terms of the QoE, and related standardization and implementation efforts. Finally, we will highlight open issues and research challenges including future work.     

Combining prospective motion correction and distortion correction for EPI: towards a comprehensive correction of motion and susceptibility-induced artifacts

Object  

State-of-the-art MR techniques that rely on echo planar imaging (EPI), such as real-time fMRI, are limited in their applicability by both subject motion and B₀ field inhomogeneities. The goal of this work is to demonstrate that in principle it is possible to accurately predict the B₀ field inhomogeneities that occur during echo planar imaging in the presence of large scale head motion and apply this knowledge for distortion correction.     

Bulk Conductivity and Defect Chemistry of Acceptor-Doped Strontium Titanate in the Quenched State

The grain bulk conductivity of acceptor-doped SrTiO₃ ceramics was investigated by the impedance analysis method after quenching from high-temperature equilibria. The influence of the oxygen partial pressure during equilibration, P ^Eq_O2, is described in terms of a defect model for titanates. From a comparison between the experimental results and the predictions of this model, a predominant ionic conductivity is concluded for a wide P ^Eq_O2 range (approximately 10⁻¹¹ to 10⁵ Pa). The influence of the ionization energy of the acceptors and of possible defect association is discussed.