Open, sesame! Introducing access control to voice services

Personal voice assistants (VAs) are shown to be vulnerable against record–and–replay, and other acoustic attacks which allow an adversary to gain unauthorized control of connected devices within a smart home. Existing defenses either lack detection and management capabilities or are too coarse-grained to enable flexible policies on par with other computing interfaces. In this work, we present Sesame, a lightweight framework for edge devices which is the first to enable fine-grained access control of smart-home voice commands. Sesame combines three components: Automatic SpeechRecognition, Natural Language Understanding (NLU) and a Policymodule. We implemented Sesame on Android devices and demonstrate that our system can enforce security policies for both Alexa and Google Home in real-time (362ms end-to-end inference time), with a lightweight (<25MB) NLU model which exhibits minimal accuracy loss compared to its non-compact equivalent

Dynamical and quasistatic structural relaxation paths in Pd_(40)Ni_(40)P_(20) glass

By sequential heat treatment of a Pd_(40)Ni_(40)P_(20) metallic glass at temperatures and durations for which α-relaxation is not possible, dynamic, and quasistatic relaxation paths below the glass transition are identified via ex situ ultrasonic measurements following each heat treatment. The dynamic relaxation paths are associated with hopping between nonequilibrium potential energy states of the glass, while the quasistatic relaxation path is associated with reversible β-relaxation events toward quasiequilibrium states. These quasiequilibrium states are identified with secondary potential energy minima that exist within the inherent energy minimum of the glass, thereby supporting the concept of the sub-basin/metabasin organization of the potential-energy landscape

Atomistic Characterization of Stochastic Cavitation of a Binary Metallic Liquid under Negative Pressure

We demonstrate the stochastic nature of cavitation in a binary metallic liquid Cu_(46)Zr_(54) during hydrostatic expansion by employing molecular dynamics (MD) simulations using a quantum mechanics (QM)-derived potential. The activation volume is obtained from MD simulations and transition-state theory. Extrapolation of the pressure dependence of the activation volume from our MD simulations to low tensile pressure agrees remarkably with macroscale cavitation experiments. We find that classical nucleation theory can predict the cavitation rate if we incorporate the Tolman length derived from the MD simulations

Predicted Optimum Composition for the Glass-Forming Ability of Bulk Amorphous Alloys: Application to Cu−Zr−Al

Metallic glasses have been established to have unique properties such as ductility, toughness, and soft magnetism with promising engineering applications. However, the glass-forming ability (GFA) has not been sufficient to synthesize the bulk metallic glasses (BMGs) required for many engineering applications. Attempts to develop the understanding of the GFA required to predict the optimum alloys have not yet been proven successful. We develop here a computational model based on molecular dynamics simulations that explains the dramatic change of GFA with alloying small amounts of Al into Cu−Zr. We find that the high GFA to form BMGs depends on a combination of three factors, (a) a low thermodynamic driving force for crystallization, (b) a high melt viscosity, and (c) large ratios of icosahedral structures in the liquid phase. These computational methods to predict these factors that suppress formation of crystal nuclei and slow the dynamic motions in the liquids are practical for in silico prediction of new alloys with optimal GFA

How the toughness in metallic glasses depends on topological and chemical heterogeneity

To gain insight into the large toughness variability observed between metallic glasses (MGs), we examine the origin of fracture toughness through bending experiments and molecular dynamics (MD) simulations for two binary MGs: Pd_(82)Si_(18) and Cu_(46)Zr_(54). The bending experiments show that Pd_(82)Si_(18) is considerably tougher than Cu_(46)Zr_(54), and the higher toughness of Pd_(82)Si_(18) is attributed to an ability to deform plastically in the absence of crack nucleation through cavitation. The MD simulations study the initial stages of cavitation in both materials and extract the critical factors controlling cavitation. We find that for the tougher Pd_(82)Si_(18), cavitation is governed by chemical inhomogeneity in addition to topological structures. In contrast, no such chemical correlations are observed in the more brittle Cu_(46)Zr_(54), where topological low coordination number polyhedra are still observed around the critical cavity. As such, chemical inhomogeneity leads to more difficult cavitation initiation in Pd_(82)Si_(18) than in Cu_(46)Zr_(54), leading to a higher toughness. The absence of chemical separation during cavitation initiation in Cu_(46)Zr_(54) decreases the energy barrier for a cavitation event, leading to lower toughness

Melanin Pigmentation and Inflammation in Human Gingiva

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141745/1/jper0701.pd

The Replication Argument for Incompatibilism

In this paper, I articulate an argument for incompatibilism about moral responsibility and determinism. My argument comes in the form of an extended story, modeled loosely on Peter van Inwagen’s “rollback argument” scenario. I thus call it “the replication argument.” As I aim to bring out, though the argument is inspired by so-called “manipulation” and “original design” arguments, the argument is not a version of either such argument—and plausibly has advantages over both. The result, I believe, is a more convincing incompatibilist argument than those we have considered previously

Meson exchange currents in electromagnetic one-nucleon emission

The role of meson exchange currents (MEC) in electron- and photon-induced one-nucleon emission processes is studied in a nonrelativistic model including correlations and final state interactions. The nuclear current is the sum of a one-body and of a two-body part. The two-body current includes pion seagull, pion-in-flight and the isobar current contributions. Numerical results are presented for the exclusive 16O(e,e'p)15N and 16O(\gamma,p)15N reactions. MEC effects are in general rather small in (e,e'p), while in (\gamma,p) they are always large and important to obtain a consistent description of (e,e'p) and (\gamma,p) data, with the same spectroscopic factors. The calculated (\gamma,p) cross sections are sensitive to short-range correlations at high values of the recoil momentum, where MEC effects are larger and overwhelm the contribution of correlations.Comment: 9 pages, 6 figure

Systematic Review of Explicit Instruments Measuring Nature Connectedness: What Do We Know and What is Next?

This systematic review assesses the methodological quality of manuscripts focusing on scales that explicitly measure nature connectedness. A literature search in six electronic databases was conducted using a search strategy based on PICO guidelines. Only peer-reviewed primary research available in English language, published between 2000 and 2021, meeting the scope of this review were included. Data from 35 studies were narratively analyzed. Their methodological quality was assessed using the COSMIN Risk of Bias checklist. Only five studies were rated as high/adequate quality. Based on the findings we make the following recommendations: (a) the need for the development of a more universal nature connectedness construct, (b) the requirement to increase the methodological quality of the scales, (c) the need to identify which the scales measure trait or state, (d) the need to increase the validate scales cross-culturally, and (e) the need to develop scales that can be employed with non-adult samples