351 research outputs found

    EXPERIMENTAL PROCEDURES FOR PRELIMINARY USER CENTRED EVALUATION OF REGIONAL AICRAFT CABIN INTERIORS IN VIRTUAL REALITY

    Get PDF
    One of the main aims of the Horizon 2020 CASTLE (Cabin System Design Towards Passenger Wellbeing) project is to deliver innovative cabin interiors solutions that maximize the comfort and wellbeing of passengers in the next future. In order to achieve such an ambitious objective, an effective HCD (Human Centred Design) approach has been put in place to derive a Human Response Model based on a holistic assessment of comfort. Therefore, the overall CASTLE HCD methodology has been conceived to provide different tools and methods to collect data on the impact that the design of each cabin item has on the user from the earliest design stages. One of these tools is represented by the use of 3D mock-ups in Virtual/Augmented Reality environments to capture data on the user\u2019s perception and to rate the level of appraisal inspired by the specific design solution. In this paper we present the experimental procedures for the Human in the loop simulations in Virtual Reality Environment of the Regional Aircraft solutions provided in the CASTLE Project. First, we introduce the overall procedure plan. Then, we describe the work done for the creation of the Virtual Environment for different scenarios (user standing in the cabin, Galley, Lavatory) and for the subjective evaluation of these cabin items

    Removing krypton from xenon by cryogenic distillation to the ppq level

    Get PDF
    The XENON1T experiment aims for the direct detection of dark matter in a cryostat filled with 3.3 tons of liquid xenon. In order to achieve the desired sensitivity, the background induced by radioactive decays inside the detector has to be sufficiently low. One major contributor is the β\beta-emitter 85^{85}Kr which is an intrinsic contamination of the xenon. For the XENON1T experiment a concentration of natural krypton in xenon nat\rm{^{nat}}Kr/Xe < 200 ppq (parts per quadrillion, 1 ppq = 1015^{-15} mol/mol) is required. In this work, the design of a novel cryogenic distillation column using the common McCabe-Thiele approach is described. The system demonstrated a krypton reduction factor of 6.4\cdot105^5 with thermodynamic stability at process speeds above 3 kg/h. The resulting concentration of nat\rm{^{nat}}Kr/Xe < 26 ppq is the lowest ever achieved, almost one order of magnitude below the requirements for XENON1T and even sufficient for future dark matter experiments using liquid xenon, such as XENONnT and DARWIN

    Augmented reality technology selection based on integrated QFD-AHP model

    Get PDF
    In the last decade, Augmented Reality has become increasingly popular. As improved performances are gathered in terms of mature hardware and software tools, we are observing the stemming of a huge number of applications of this technology both in the entertainment and in the industrial domains. On the one hand, such applications are usually claimed to bring benefits in terms of productivity or enhancement of the human\u2019s capability to perform tasks. On the other hand, researchers and developers seem not to adequately consider the different meanings that AR assumes when implemented through visualization devices that can differ significantly in nature and in their capability to provide a mixed real-virtual scenario. In this paper, we describe a user-centred method based on an integrated QFD-AHP approach to select the best visualization display technology with regard to a specific application context. The aim is to establish a repeatable and documented process for the identification of the technology that best suits and mitigates the acceptability risks of the transition from a legacy working environment to an AR based operational environment. The method has been developed in the framework of the RETINA (Resilient Synthetic Vision for Advanced Control Tower Air Navigation Service Provision) project involving the end users, in this case, air traffic controllers. Nevertheless, it can be generalised and applied to other contexts of use. Furthermore, in order to be resilient to the fast, technological development in AR, it can be used to update the results as improvements arise in the performance level of the display devices in a specific technology

    Lowering the radioactivity of the photomultiplier tubes for the XENON1T dark matter experiment

    Get PDF
    The low-background, VUV-sensitive 3-inch diameter photomultiplier tube R11410 has been developed by Hamamatsu for dark matter direct detection experiments using liquid xenon as the target material. We present the results from the joint effort between the XENON collaboration and the Hamamatsu company to produce a highly radio-pure photosensor (version R11410-21) for the XENON1T dark matter experiment. After introducing the photosensor and its components, we show the methods and results of the radioactive contamination measurements of the individual materials employed in the photomultiplier production. We then discuss the adopted strategies to reduce the radioactivity of the various PMT versions. Finally, we detail the results from screening 216 tubes with ultra-low background germanium detectors, as well as their implications for the expected electronic and nuclear recoil background of the XENON1T experiment.Comment: 10 pages, 5 figure

    Search for Two-Neutrino Double Electron Capture of 124^{124}Xe with XENON100

    Get PDF
    Two-neutrino double electron capture is a rare nuclear decay where two electrons are simultaneously captured from the atomic shell. For 124^{124}Xe this process has not yet been observed and its detection would provide a new reference for nuclear matrix element calculations. We have conducted a search for two-neutrino double electron capture from the K-shell of 124^{124}Xe using 7636 kg\cdotd of data from the XENON100 dark matter detector. Using a Bayesian analysis we observed no significant excess above background, leading to a lower 90 % credibility limit on the half-life T1/2>6.5×1020T_{1/2}>6.5\times10^{20} yr. We also evaluated the sensitivity of the XENON1T experiment, which is currently being commissioned, and find a sensitivity of T1/2>6.1×1022T_{1/2}>6.1\times10^{22} yr after an exposure of 2 t\cdotyr.Comment: 6 pages, 4 figure

    Search for Event Rate Modulation in XENON100 Electronic Recoil Data

    Get PDF
    We have searched for periodic variations of the electronic recoil event rate in the (2-6) keV energy range recorded between February 2011 and March 2012 with the XENON100 detector, adding up to 224.6 live days in total. Following a detailed study to establish the stability of the detector and its background contributions during this run, we performed an un-binned profile likelihood analysis to identify any periodicity up to 500 days. We find a global significance of less than 1 sigma for all periods suggesting no statistically significant modulation in the data. While the local significance for an annual modulation is 2.8 sigma, the analysis of a multiple-scatter control sample and the phase of the modulation disfavor a dark matter interpretation. The DAMA/LIBRA annual modulation interpreted as a dark matter signature with axial-vector coupling of WIMPs to electrons is excluded at 4.8 sigma.Comment: 6 pages, 4 figure

    EEG alpha power is modulated by attentional changes during cognitive tasks and virtual reality immersion

    Get PDF
    Variations in alpha rhythm have a significant role in perception and attention. Recently, alpha decrease has been associated with externally directed attention, especially in the visual domain, whereas alpha increase has been related to internal processing such as mental arithmetic. However, the role of alpha oscillations and how the different components of a task (processing of external stimuli, internal manipulation/representation, and task demand) interact to affect alpha power are still unclear. Here, we investigate how alpha power is differently modulated by attentional tasks depending both on task difficulty (less/more demanding task) and direction of attention (internal/external). To this aim, we designed two experiments that differently manipulated these aspects. Experiment 1, outside Virtual Reality (VR), involved two tasks both requiring internal and external attentional components (intake of visual items for their internal manipulation) but with different internal task demands (arithmetic vs. reading). Experiment 2 took advantage of the VR (mimicking an aircraft cabin interior) to manipulate attention direction: it included a condition of VR immersion only, characterized by visual external attention, and a condition of a purely mental arithmetic task during VR immersion, requiring neglect of sensory stimuli. Results show that: (1) In line with previous studies, visual external attention caused a significant alpha decrease, especially in parieto-occipital regions; (2) Alpha decrease was significantly larger during the more demanding arithmetic task, when the task was driven by external visual stimuli; (3) Alpha dramatically increased during the purely mental task in VR immersion, whereby the external stimuli had no relation with the task. Our results suggest that alpha power is crucial to isolate a subject from the environment, and move attention from external to internal cues. Moreover, they emphasize that the emerging use of VR associated with EEG may have important implications to study brain rhythms and support the design of artificial systems

    Observation and applications of single-electron charge signals in the XENON100 experiment

    Get PDF
    The XENON100 dark matter experiment uses liquid xenon in a time projection chamber (TPC) to measure xenon nuclear recoils resulting from the scattering of dark matter Weakly Interacting Massive Particles (WIMPs). In this paper, we report the observation of single-electron charge signals which are not related to WIMP interactions. These signals, which show the excellent sensitivity of the detector to small charge signals, are explained as being due to the photoionization of impurities in the liquid xenon and of the metal components inside the TPC. They are used as a unique calibration source to characterize the detector. We explain how we can infer crucial parameters for the XENON100 experiment: the secondary-scintillation gain, the extraction yield from the liquid to the gas phase and the electron drift velocity

    Human-in-the-loop evaluation of an augmented reality based interface for the airport control tower

    Get PDF
    An innovative airport control tower concept based on the use of modern augmented reality technologies has been developed and validated by means of human-in-the-loop experiments in a simulated environment. An optical-based augmented reality interface underpins the proposed concept that consists in providing air traffic control operators in the airport control tower with complete head-up information, as opposed to the current mix of information retrieval through both head-up real view and head-down interfaces. Specific measurement of the time spent by the operator working in either head-up or head-down position, show that the proposal has a clear effect in stimulating the air traffic control operator to work in a head-up position more than in a head-down position, with positive effects on his/her situational awareness and perceived workload, especially when dealing with low visibility conditions operational scenarios

    Separation of track- and shower-like energy deposits in ProtoDUNE-SP using a convolutional neural network

    Get PDF
    Liquid argon time projection chamber detector technology provides high spatial and calorimetric resolutions on the charged particles traversing liquid argon. As a result, the technology has been used in a number of recent neutrino experiments, and is the technology of choice for the Deep Underground Neutrino Experiment (DUNE). In order to perform high precision measurements of neutrinos in the detector, final state particles need to be effectively identified, and their energy accurately reconstructed. This article proposes an algorithm based on a convolutional neural network to perform the classification of energy deposits and reconstructed particles as track-like or arising from electromagnetic cascades. Results from testing the algorithm on experimental data from ProtoDUNE-SP, a prototype of the DUNE far detector, are presented. The network identifies track- and shower-like particles, as well as Michel electrons, with high efficiency. The performance of the algorithm is consistent between experimental data and simulation
    corecore