Service social des groupes en contexte multiculturel

Ce court article est un commentaire aux propos de Kenneth L. Chau sur les expériences que vivent les membres des communautés culturelles en Amérique. L'auteure fait ressortir deux aspects de ce vécu, à savoir la couleur et l'adaptation, qui se traduisent, d'une part, par des difficultés tant personnelles que collectives au niveau de l'identité et de l'estime de soi et, d'autre part, par diverses stratégies d'adaptation, elles-mêmes sources de problèmes. Pernell réexamine les objectifs du service social des groupes en tenant compte du vécu des communautés ethniques et, par conséquent, des particularités qu'implique l'intervention en contexte multiculturel

Superconducting Qubits Coupled to Nanoelectromechanical Resonators: An Architecture for Solid-State Quantum Information Processing

We describe the design for a scalable, solid-state quantum-information-processing architecture based on the integration of GHz-frequency nanomechanical resonators with Josephson tunnel junctions, which has the potential for demonstrating a variety of single- and multi-qubit operations critical to quantum computation. The computational qubits are eigenstates of large-area, current-biased Josephson junctions, manipulated and measured using strobed external circuitry. Two or more of these phase qubits are capacitively coupled to a high-quality-factor piezoelectric nanoelectromechanical disk resonator, which forms the backbone of our architecture, and which enables coherent coupling of the qubits. The integrated system is analogous to one or more few-level atoms (the Josephson junction qubits) in an electromagnetic cavity (the nanomechanical resonator). However, unlike existing approaches using atoms in electromagnetic cavities, here we can individually tune the level spacing of the ``atoms'' and control their ``electromagnetic'' interaction strength. We show theoretically that quantum states prepared in a Josephson junction can be passed to the nanomechanical resonator and stored there, and then can be passed back to the original junction or transferred to another with high fidelity. The resonator can also be used to produce maximally entangled Bell states between a pair of Josephson junctions. Many such junction-resonator complexes can assembled in a hub-and-spoke layout, resulting in a large-scale quantum circuit. Our proposed architecture combines desirable features of both solid-state and cavity quantum electrodynamics approaches, and could make quantum information processing possible in a scalable, solid-state environment.Comment: 20 pages, 14 separate low-resolution jpeg figure

Implicit Smartphone User Authentication with Sensors and Contextual Machine Learning

Authentication of smartphone users is important because a lot of sensitive data is stored in the smartphone and the smartphone is also used to access various cloud data and services. However, smartphones are easily stolen or co-opted by an attacker. Beyond the initial login, it is highly desirable to re-authenticate end-users who are continuing to access security-critical services and data. Hence, this paper proposes a novel authentication system for implicit, continuous authentication of the smartphone user based on behavioral characteristics, by leveraging the sensors already ubiquitously built into smartphones. We propose novel context-based authentication models to differentiate the legitimate smartphone owner versus other users. We systematically show how to achieve high authentication accuracy with different design alternatives in sensor and feature selection, machine learning techniques, context detection and multiple devices. Our system can achieve excellent authentication performance with 98.1% accuracy with negligible system overhead and less than 2.4% battery consumption.Comment: Published on the IEEE/IFIP International Conference on Dependable Systems and Networks (DSN) 2017. arXiv admin note: substantial text overlap with arXiv:1703.0352

Secure Pick Up: Implicit Authentication When You Start Using the Smartphone

We propose Secure Pick Up (SPU), a convenient, lightweight, in-device, non-intrusive and automatic-learning system for smartphone user authentication. Operating in the background, our system implicitly observes users' phone pick-up movements, the way they bend their arms when they pick up a smartphone to interact with the device, to authenticate the users. Our SPU outperforms the state-of-the-art implicit authentication mechanisms in three main aspects: 1) SPU automatically learns the user's behavioral pattern without requiring a large amount of training data (especially those of other users) as previous methods did, making it more deployable. Towards this end, we propose a weighted multi-dimensional Dynamic Time Warping (DTW) algorithm to effectively quantify similarities between users' pick-up movements; 2) SPU does not rely on a remote server for providing further computational power, making SPU efficient and usable even without network access; and 3) our system can adaptively update a user's authentication model to accommodate user's behavioral drift over time with negligible overhead. Through extensive experiments on real world datasets, we demonstrate that SPU can achieve authentication accuracy up to 96.3% with a very low latency of 2.4 milliseconds. It reduces the number of times a user has to do explicit authentication by 32.9%, while effectively defending against various attacks.Comment: Published on ACM Symposium on Access Control Models and Technologies (SACMAT) 201

Reflexion M\"ossbauer analysis of the in situ oxidation products hydroxycarbonate green rust

The purpose of this study is to determine the nature of the oxidation products of FeII-III hydroxycarbonate FeII4FeIII2(OH)12CO3~3H2O (green rust GR(CO32-)) by using the miniaturised M\"ossbauer spectrometer MIMOS II. Two M\"ossbauer measurements methods are used: method (i) with green rust pastes coated with glycerol and spread into Plexiglas sample holders, and method (ii) with green rust pastes in the same sample holders but introduced into a gas-tight cell with a beryllium window under a continuous nitrogen flow. Method (ii) allows us to follow the continuous deprotonation of GR(CO32-) into the fully ferric deprotonated form FeIII6O4(OH)8CO3~3H2O by adding the correct amount of H2O2, without any further oxidation or degradation of the samples

Ethnocentric Behaviour and Business Performance of Multinational Enterprises (MNES): Evidence From South-West Nigeria

The globalised world has become more integrated and has witnessed an unprecedented dispersal of Multinational Enterprises (MNEs) across various nations and regions of the world. Most of these MNEs advertently or inadvertently exhibit tendencies that show them off as ethnocentric- possessing superior culture than those of their host country. This study assessed the effects of ethnocentric behaviours on the performance of MNEs in the South West of Nigeria. Adopting a survey design, the study made use of primary data collected mainly through administering a set of questionnaire to 207 management staff of selected MNEs from Oyo, Lagos and Ogun states respectively. Findings inter alia revealed that: engaging expatriates in strategic positions by MNE's leads to increased operating costs; foreign culture of MNE's home country negatively affects the local acceptance of management techniques by employees in host countries and MNE's standardized marketing strategies encouraged customers' loyalty and patronage in the Nigeria business environments. The work among other things, recommends that local employees in host nations must be incorporated into key decisions to aid MNE's continuous effectiveness. The work, in addition to that, also advised that MNE's should guide against culture shock i.e. the disorientation, cultural risks and stress associated with being in a foreign environment