17,101 research outputs found

    Introduction to the new usability

    Get PDF
    This paper introduces the motivation for and concept of the "new usability" and positions it against existing approaches to usability. It is argued that the contexts of emerging products and systems mean that traditional approaches to usability engineering and evaluation are likely to prove inappropriate to the needs of "digital consumers." The paper briefly reviews the contributions to this special issue in terms of their relation to the idea of the "new usability" and their individual approaches to dealing with contemporary usability issues. This helps provide a background to the "new usability" research agenda, and the paper ends by posing what are argued to be the central challenges facing the area and those which lie at the heart of the proposed research agenda

    Effects of cosmic rays on single event upsets

    Get PDF
    Assistance was provided to the Brookhaven Single Event Upset (SEU) Test Facility. Computer codes were developed for fragmentation and secondary radiation affecting Very Large Scale Integration (VLSI) in space. A computer controlled CV (HP4192) test was developed for Terman analysis. Also developed were high speed parametric tests which are independent of operator judgment and a charge pumping technique for measurement of D(sub it) (E). The X-ray secondary effects, and parametric degradation as a function of dose rate were simulated. The SPICE simulation of static RAMs with various resistor filters was tested

    AdS/CFT and the Information Paradox

    Get PDF
    The information paradox in the quantum evolution of black holes is studied within the framework of the AdS/CFT correspondence. The unitarity of the CFT strongly suggests that all information about an initial state that forms a black hole is returned in the Hawking radiation. The CFT dynamics implies an information retention time of order the black hole lifetime. This fact determines many qualitative properties of the non-local effects that must show up in a semi-classical effective theory in the bulk. We argue that no violations of causality are apparent to local observers, but the semi-classical theory in the bulk duplicates degrees of freedom inside and outside the event horizon. Non-local quantum effects are required to eliminate this redundancy. This leads to a breakdown of the usual classical-quantum correspondence principle in Lorentzian black hole spacetimes.Comment: 16 pages, harvmac, reference added, minor correction
    corecore