1,224 research outputs found

    Social cognition in the age of human–robot interaction

    Get PDF
    Artificial intelligence advances have led to robots endowed with increasingly sophisticated social abilities. These machines speak to our innate desire to perceive social cues in the environment, as well as the promise of robots enhancing our daily lives. However, a strong mismatch still exists between our expectations and the reality of social robots. We argue that careful delineation of the neurocognitive mechanisms supporting human–robot interaction will enable us to gather insights critical for optimising social encounters between humans and robots. To achieve this, the field must incorporate human neuroscience tools including mobile neuroimaging to explore long-term, embodied human–robot interaction in situ. New analytical neuroimaging approaches will enable characterisation of social cognition representations on a finer scale using sensitive and appropriate categorical comparisons (human, animal, tool, or object). The future of social robotics is undeniably exciting, and insights from human neuroscience research will bring us closer to interacting and collaborating with socially sophisticated robots

    Air pollution

    Get PDF

    Investigation of a direction sensitive sapphire detector stack at the 5 GeV electron beam at DESY-II

    Full text link
    Extremely radiation hard sensors are needed in particle physics experiments to instrument the region near the beam pipe. Examples are beam halo and beam loss monitors at the Large Hadron Collider, FLASH or XFEL. Currently artificial diamond sensors are widely used. In this paper single crystal sapphire sensors are considered as a promising alternative. Industrially grown sapphire wafers are available in large sizes, are of low cost and, like diamond sensors, can be operated without cooling. Here we present results of an irradiation study done with sapphire sensors in a high intensity low energy electron beam. Then, a multichannel direction-sensitive sapphire detector stack is described. It comprises 8 sapphire plates of 1 cm^2 size and 525 micro m thickness, metallized on both sides, and apposed to form a stack. Each second metal layer is supplied with a bias voltage, and the layers in between are connected to charge-sensitive preamplifiers. The performance of the detector was studied in a 5 GeV electron beam. The charge collection efficiency measured as a function of the bias voltage rises with the voltage, reaching about 10 % at 950 V. The signal size obtained from electrons crossing the stack at this voltage is about 22000 e, where e is the unit charge. The signal size is measured as a function of the hit position, showing variations of up to 20 % in the direction perpendicular to the beam and to the electric field. The measurement of the signal size as a function of the coordinate parallel to the electric field confirms the prediction that mainly electrons contribute to the signal. Also evidence for the presence of a polarisation field was observed.Comment: 13 pages, 7 figures, 3 table

    A Performance Comparison Using HPC Benchmarks: Windows HPC Server 2008 and Red Hat Enterprise Linux 5

    Get PDF
    This document was developed with support from the National Science Foundation (NSF) under Grant No. 0910812 to Indiana University for ”FutureGrid: An Experimental, High-Performance Grid Test-bed.” Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the NSF.A collection of performance benchmarks have been run on an IBM System X iDataPlex cluster using two different operating systems. Windows HPC Server 2008 (WinHPC) and Red Hat Enterprise Linux v5.4 (RHEL5) are compared using SPEC MPI2007 v1.1, the High Performance Computing Challenge (HPCC) and National Science Foundation (NSF) acceptance test benchmark suites. Overall, we find the performance of WinHPC and RHEL5 to be equivalent but significant performance differences exist when analyzing specific applications. We focus on presenting the results from the application benchmarks and include the results of the HPCC microbenchmark for completeness

    Effect of inhomogeneous distribution of non-metallic inclusions on crack path deflection in G42CrMo4 steel at different loading rates

    Get PDF
    An inhomogeneous distribution of non-metallic inclusions can result from the steel casting process.The aim of the present study was to investigate the damaging effect of an inhomogeneous distribution of nonmetallic inclusions on the crack extension behavior. To this end, the fracture toughness behavior in terms ofquasi-static J-?a curves was determined at room temperature. Additionally, dynamic fracture mechanics tests inan instrumented Charpy impact-testing machine were performed. The fracture surface of fracture mechanicsspecimens was analyzed by means of scanning electron microscopy.It was shown that an inhomogeneous distribution significantly affected the path and, therefore, the plane ofcrack growth. Especially clusters of non-metallic inclusions with a size of up to 200 ?m exhibited a very lowcrack growth resistance. Due to the damaging effect of the clusters, the growing crack was strongly deflectedtowards the cluster. Furthermore, crack tip blunting was completely inhibited when inclusions were located atthe fatigue precrack tip. Due to the large size of the non-metallic inclusion clusters, the height differenceintroduced by crack path deflection was significantly larger than the stretch zone height due to the crack tipblunting. However, the crack path deflection introduced by a cluster was not associated with a toughnessincreasing mechanism. The dynamic loading ( 1 0.5 5 s MPam 10 ? ? K? ) did not result in a transition from ductile fracture to brittle fracture. However, the crack growth resistance decreased with increased loading rate. This was attributed to the higher portion of relatively flat regions where the dimples were less distinct
    • …
    corecore