Automatic Sensing of Speech Activity and Correlation with Mood Changes

he association between social relationships and psychological health has been established fairly recently, in the last 30-40 years, relying on survey-based methods to record past activities and the psychological responses in individuals. However, using the self-reporting methods for capturing social behavior exhibits a number of shortcomings including recall bias, memory dependence, and a high end user effort for a continuous long-term monitoring. In contrast, automated sensing techniques for monitoring social activity, and in general, human behavior, has a potential to provide more objective measurements thus to overcome the shortcomings of self-reporting methods. In this paper, we present a privacy preserving approach to detect one component of social interactions - the speech activity, through the use of off-the-shelf accelerometers. Furthermore, we used the accelerometer based speech detection method to investigate the correlation between the amount of speech (which is an aspect that reflects the participation in verbal social interactions) and mood changes. Our pilot study suggested that verbal interactions are an important factor that has an impact on individuals’ mood, while the study also demonstrated the potential of automated capturing social activity comparable to the use of gold standard surveys

Toward Operando Characterization of Interphases in Batteries

Electrode/electrolyte interfaces are the most importantand leastunderstood components of Li-ion and next-generation batteries. Animproved understanding of interphases in batteries will undoubtedlylead to breakthroughs in the field. Traditionally, evaluating thoseinterphases involves using ex situ surface sensitiveand/or imaging techniques. Due to their very dynamic and reactivenature, ex situ sample manipulation is undesirable.From this point of view, operando surface sensitivetechniques represent a major opportunity to push boundaries in batterydevelopment. While numerous bulk spectroscopic, scattering, and imagingtechniques are well established and widely used, surface sensitive operando techniques remain challenging and, to a largerextent, restricted to the model systems. Here, we give a perspectiveon techniques with the potential to characterize solid/liquid interfacesin both model and realistic battery configurations. The focus is ontechniques that provide chemical and structural information at lengthand time scales relevant for the solid electrolyte interphase (SEI)formation and evolution, while also probing representative electrodeareas. We highlight the following techniques: vibrational spectroscopy,X-ray photoelectron spectroscopy (XPS), neutron and X-ray reflectometry,and grazing incidence scattering techniques. Comprehensive overviews,as well as promises and challenges, of these techniques when used operando on battery interphases are discussed in detail

Virtual uniforms: using sound frequencies for grouping individuals

In this paper, we present the concept of grouping individuals and detecting their proximity by emitting/receiving inaudible tones using their mobile phones. The inspiration stems from uniforms metaphor (of different colors) that groups subjects based on the roles, occupations or teams. The goal is to get an insight into the social context and social interaction patterns

The duration of daily activities has no impact on measures of overall wellbeing

It is widely assumed that the longer we spend in happier activities the happier we will be. In an intensive study of momentary happiness, we show that, in fact, longer time spent in happier activities does not lead to higher levels of reported happiness overall. This finding is replicated with different samples (student and diverse, multi-national panel), measures and methods of analysis. We explore different explanations for this seemingly paradoxical finding, providing fresh insight into the factors that do and do not affect the relationship between how happy we report feeling as a function of how long it lasts. This work calls into question the assumption that spending more time doing what we like will show up in making us happier, presenting a fundamental challenge to the validity of current tools used to measure happiness

Polysulfide Speciation and Migration in Catholyte Lithium−Sulfur Cells

Semi-liquid catholyte Lithium−Sulfur (Li−S) cells have shown to be a promising path to realize high energy density energy storage devices. In general, Li−S cells rely on the conversion of elemental sulfur to soluble polysulfide species. In the case of catholyte cells, the active material is added through polysulfide species dissolved in the electrolyte. Herein, we use operando Raman spectroscopy to track the speciation and migration of polysulfides in the catholyte to shed light on the processes taking place. Combined with ex-situ surface and electrochemical analysis we show that the migration of polysulfides is central in order to maximize the performance in terms of capacity (active material utilization) as well as interphase stability on the Li-metal anode during cycling. More specifically we show that using a catholyte where the polysulfides have the dual roles of active material and conducting species, e. g. no traditional Li-salt (such as LiTFSI) is present, results in a higher mobility and faster migration of polysulfides. We also reveal how the formation of long chain polysulfides in the catholyte is delayed during charge as a result of rapid formation and migration of shorter chain species, beneficial for reaching higher capacities. However, the depletion of ionic species during the last stage of charge, due to the conversion to and precipitation of elemental sulfur on the cathode support, results in polarization of the cell before full conversion can be achieved

A high-power and fast charging Li-ion battery with outstanding cycle-life

Electrochemical energy storage devices based on Li-ion cells currently power almost all electronic devices and power tools. The development of new Li-ion cell configurations by incorporating innovative functional components (electrode materials and electrolyte formulations) will allow to bring this technology beyond mobile electronics and to boost performance largely beyond the state-of-the-art. Here we demonstrate a new full Li-ion cell constituted by a high-potential cathode material, i.e. LiNi0.5Mn1.5O4, a safe nanostructured anode material, i.e. TiO2, and a composite electrolyte made by a mixture of an ionic liquid suitable for high potential applications, i.e. Pyr1,4PF6, a lithium salt, i.e. LiPF6, and standard organic carbonates. The final cell configuration is able to reversibly cycle lithium for thousands of cycles at 1000 mAg-1 and a capacity retention of 65% at cycle 2000. © 2017 The Author(s)