Low-cost VR Collaborative System equipped with Haptic Feedback

International audienceIn this paper, we present a low-cost virtual reality (VR) collaborative system equipped with a haptic feedback sensation system. This system is composed of a Kinect sensor for bodies and gestures detection, a microcontroller and vibrators to simulate outside interactions, and smartphone powered cardboard, all of this are put into a network implemented with Unity 3D game engine. CCS CONCEPTS • Interaction paradigms → Virtual reality; Collaborative interaction; • Hardware → Sensors and actuators; Wireless devices; KEYWORDS collaborative virtual reality, haptic feedback system

DASHbed: a testbed framework for large scale empirical evaluation of real-time DASH in wireless scenarios

Recent years have witnessed an explosion of multimedia traffic carried over the Internet. Video-on-demand and live streaming services are the most dominant services. To ensure growth, many streaming providers have invested considerable time and effort to keep pace with ever-increasing users’ demand for better quality and stall abolition. HTTP adaptive streaming (HAS) algorithms are at the core of every major streaming provider service. Recent years have seen sustained development in HAS algorithms. Currently, to evaluate their proposed solutions, researchers need to create a framework and numerous state-of-the-art algorithms. Often, these frameworks lack flexibility and scalability, covering only a limited set of scenarios. To fill this gap, in this paper we propose DASHbed, a highly customizable real-time framework for testing HAS algorithms in a wireless environment. Due to its low memory requirement, DASHbed offers a means of running large-scale experiments with a hundred competing players. Finally, we supplement the proposed framework with a dataset consisting of results for five HAS algorithms tested in various evaluated scenarios. The dataset showcases the abilities of DASHbed and presents the adaptation metrics per segment in the generated content (such as switches, buffer-level, P.1203.1 values, delivery rate, stall duration, etc.), which can be used as a baseline when researchers compare the output of their proposed algorithm against the state-of-the-art algorithms

An unusual plank-shaped nematogen with a graphene nanoribbon core

A [12]phenacene exclusively decorated with four lateral hexylester substituents self-assembles into a nematic liquid crystal glass on cooling after melting at high temperature. This uniaxial nematic organization of a plank-shaped nanographene is unprecedented and in strong contrast to the common design rules for liquid crystals. Highly birefringent samples emitting polarized fluorescence can be obtained in homogeneously planar or twisted waveguiding configurations that are stable against crystallization at and below room temperature and up to 100 °C

Observer-Based Robust H_infty Control for Uncertain Discrete-Time T-S Fuzzy Systems

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Regiospecific synthesis of tetrasusubstituted phthalocyanines and their liquid crystalline order

International audienceMetal-free and metal(II) all-endo-tetraaalkoxy-phthalocyanines of C 4h symmetry are synthesised regio-specifically from 3-(2-butyloctyloxy)phthalonitrile with lithium octanolate and subsequent metal ion exchange. The voluminous, yet not overly large, and racemically disordered alkoxy substituent not only renders the cyclotetramerisation regiospecific, but also leads to liquid crystalline self-assembly with attainable clearing temperatures and persisting columnar organisation at room temperature....

Concentration-dependent characteristics of a complex coacervate

In this work, we have comprehensively and systematically investigated the influence of the initial concentration of oppositely charged polyelectrolyte solutions on the interaction strength, interfacial tension and local structure of the coacervate phase generated at charge stoichiometry in a PDADMAC/PANa model system. We have shown for the first time that the concentration has a direct and significant impact on the complexation strength between the two polyelectrolytes, leading to lighter coacervates with constant mass yield and increasing network mesh and decreasing liquid-liquid interfacial tensions until a critical concentration where oppositely charged chains no longer interact, generating the so-called self-supressed coacervate single phase (SSCV). An effect that is due the free counterions present in the solution, whose concentration increases with that of the PE polyelectrolytes and gradually screens the electrostatic complexation. These characteristics will certainly have an impact on the capacity of these coacervates, objects of great scientific and technical interest today, to be efficiently stabilized, to encapsulate active principles and to serve as bioreactors

Tactile Internet to Share VR users’ Experiences

International audienceWe propose the concept of "Tactile Internet"(Tac-I) that will be the next evolution of the Internet of Things (IoT). It enables sharing experiences of others with the sense of touch. In our case, Tac-I allows to multicast vibrotactile sensations from one node to multiple nodes via Internet. We developed vibrotactile shared devices which are physical bracelets connected between them through Cloud platform. We use the WebRTC as communication protocol to exchange data between tactile bracelets. Users can access Tac-I Web using a smartphone or Tablet and experience the vibrotactile sensation by manipulating virtual objects in a virtual reality environment from a Web browser. Multiple vibrotactile bracelets would be connected to the Cloud and transmit the tactile information from one node to another one or to multiple ones

Impact of aging on the phase behavior of cocoa butter and copra oil blends

Aging of cocoa butter (CB)/copra oil (CO) binary blends (noted CB/CO) is investigated through a multi-technique approach. Indeed, the phase behavior of non-aged and 30 days-aged cocoa butter/copra oil binary blends (CB/CO) at 4°C is studied, using a combination of Nuclear Magnetic Resonance (NMR), Differential Scanning Calorimetry (DSC) and X-Ray Diffraction (XRD). During subsequent heating from 4°C to 40°C, solid fat content depression between 15°C and 20°C is shown with NMR, with the most pronounced occurring at two different compositions for the non-aged (60% CO addition in CB) and for the 30 days-aged mixtures (80% CO addition in CB). In agreement, DSC exposes melting enthalpy and melting temperature depression for the aged-blend 80/20 CB/CO. XRD highlights fat interactions at the nanoscopic scale and allows the precise attribution of polymorphic transitions perceived with DSC. The melt-mediated transformation of CB crystals from β'2-2L to β2-3L is shown in non-aged blends containing 0% to 10% of CO in CB, whereas it is shown to occur in blends containing 0% to 60% CO in CB for the 30 days aged-blends. As a result of this study, all the results obtained with the various methods are used to build the very first complete pseudo-phase diagram of 4°C-aged CB/CO blends, it highlights the shift of the eutectic points after 30 days of storage. We think that such a fundamental work can bring new understanding of a well-known issue as encountered in chocolate-based products storage