110 research outputs found

    Memory switches based on metal oxide thin films

    Get PDF
    MnO.sub.2-x thin films (12) exhibit irreversible memory switching (28) with an OFF/ON resistance ratio of at least about 10.sup.3 and the tailorability of ON state (20) resistance. Such films are potentially extremely useful as a connection element in a variety of microelectronic circuits and arrays (24). Such films provide a pre-tailored, finite, non-volatile resistive element at a desired place in an electric circuit, which can be electrically turned OFF (22) or disconnected as desired, by application of an electrical pulse. Microswitch structures (10) constitute the thin film element, contacted by a pair of separate electrodes (16a, 16b) and have a finite, pre-selected ON resistance which is ideally suited, for example, as a programmable binary synaptic connection for electronic implementation of neural network architectures. The MnO.sub.2-x microswitch is non-volatile, patternable, insensitive to ultraviolet light, and adherent to a variety of insulating substrates (14), such as glass and silicon dioxide-coated silicon substrates

    Hybrid analog-digital associative neural network

    Get PDF
    Random access memory is used to store synaptic information in the form of a matrix of rows and columns of binary digits. N rows read in sequence are processed through switches and resistors, and a summing amplifier to N neural amplifiers in sequence, one row for each amplifier, using a first array of sample-and-hold devices S/H1 for commutation. The outputs of the neural amplifiers are stored in a second array of sample-and-hold devices S/H2 so that after N rows are processed, all of the second array of sample-and-hold devices are updated. A second memory may be added for binary values of 0 and -1, and processed simultaneously with the first to provide for values of 1, 0, and -1, the results of which are combined in a difference amplifier

    Hybrid analog-digital associative neural network

    Get PDF
    Random access memory is used to store synaptic information in the form of a matrix of rows and columns of binary digits. N rows read in sequence are processed through switches and resistors, and a summing amplifier to N neural amplifiers in sequence, one row for each amplifier, using a first array of sample-and-hold devices S/H1 for commutation. The outputs of the neural amplifiers are stored in a second array of sample-and-hold devices S/H2 so that after N rows are processed, all of said second array of sample-and-hold devices are updated. A second memory may be added for binary values of 0 and -1, and processed simultaneously with the first to provide for values of 1, 0, and -1, the results of which are combined in a difference amplifier

    High density associative memory

    Get PDF
    A multi-layered, thin-film, digital memory having associative recall. There is a first memory matrix and a second memory matrix. Each memory matrix comprises, a first layer comprising a plurality of electrically separated row conductors; a second layer comprising a plurality of electrically separated column conductors intersecting but electrically separated from the row conductors; and, a plurality of resistance elements electrically connected between the row condutors and the column conductors at respective intersections of the row conductors and the column conductors, each resistance element comprising, in series, a first resistor of sufficiently high ohmage to conduct a sensible element current therethrough with virtually no heat-generating power consumption when a low voltage as employed in thin-film applications is applied thereacross and a second resistor of sufficiently high ohmage to conduct no sensible current therethrough when a low voltage as employed in thin-film applications is applied thereacross, the second resistor having the quality of breaking down to create a short therethrough upon the application of a breakdown level voltage across the first and second resistors

    SLIP4EX- a program for routine slope stability analysis to include the effects of vegetation, reinforcement and hydrological changes

    Get PDF
    SLIP4EX is a straightforward computer program developed in connection with the EU funded ECOSLOPES project for routine stability analysis and the assessment of the contribution of vegetation to slope stability. The slope section is drawn up and dimensions and parameters are fed in to the Microsoft Excel based program for stability calculations and comparisons of Factors of Safety using different methods of analysis (Bishop, Janbu, Fellenius, Simple, Greenwood). The background and assumptions involved in the derivation of each of the methods is briefly described. The simplicity of the program enables the user to understand the nature of the analysis, explore the parameter assumptions made and compare the different methods of analysis. Soil reinforcement by geosynthetic layers or anchors, and vegetation effects of enhanced cohesion, changed water pressures, mass of vegetation, wind forces and root reinforcement forces are readily included in the analysis. The program is freely available on request from the author

    An electroluminescent-piezoelectric flat-panel display device

    Full text link
    A flat-panel, line display consisting of electroluminescent ZnS---Cu phosphors (EL) adjacent to piezoelectric voltage transformer elements (PE) has been fabricated to provide a controlled-movement luminescent light spot. Electroluminescence is excited by the electric fields generated at the surface of a piezoelectric element driven at its resonant frequency. The display is made up of thirty PE-EL units connected electrically in parallel, each unit resonating at a different frequency. Movement of the light spot over the face of the display is produced by frequency modulation of the voltages applied to the piezoelectric array, in the manner of a sweep frequency. Synchronized amplitude modulation permits the light spot to be localized and its movement to be controlled. The display has a sweep frequency range extending from 30 to 60 kc/s. PE-EL units under continuous operation generate 40 ft lamberts at 8[middle dot]8 Vrms, and can generate over 100 ft lamberts by overdriving at 40Vrms. In sweep operation at 100 c/s, the light output is 40 ft lamberts at 35 Vrms. Power consumption in this mode is less than 10 mW. EL fatigue is analyzed and minimized in this display sweep technique.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/32284/1/0000351.pd

    Zero Frequency Current Noise for the Double Tunnel Junction Coulomb Blockade

    Full text link
    We compute the zero frequency current noise numerically and in several limits analytically for the coulomb blockade problem consisting of two tunnel junctions connected in series. At low temperatures over a wide range of voltages, capacitances, and resistances it is shown that the noise measures the variance in the number of electrons in the region between the two tunnel junctions. The average current, on the other hand, only measures the mean number of electrons. Thus, the noise provides additional information about transport in these devices which is not available from measuring the current alone.Comment: 33 pages, 10 figure

    Time intervals and routes to diagnosis for lung cancer in 10 jurisdictions: cross-sectional study findings from the International Cancer Benchmarking Partnership (ICBP)

    Get PDF
    OBJECTIVE: Differences in time intervals to diagnosis and treatment between jurisdictions may contribute to previously reported differences in stage at diagnosis and survival. The International Cancer Benchmarking Partnership Module 4 reports the first international comparison of routes to diagnosis and time intervals from symptom onset until treatment start for patients with lung cancer. DESIGN: Newly diagnosed patients with lung cancer, their primary care physicians (PCPs) and cancer treatment specialists (CTSs) were surveyed in Victoria (Australia), Manitoba and Ontario (Canada), Northern Ireland, England, Scotland and Wales (UK), Denmark, Norway and Sweden. Using Wales as the reference jurisdiction, the 50th, 75th and 90th percentiles for intervals were compared using quantile regression adjusted for age, gender and comorbidity. PARTICIPANTS: Consecutive newly diagnosed patients with lung cancer, aged ≥40 years, diagnosed between October 2012 and March 2015 were identified through cancer registries. Of 10 203 eligible symptomatic patients contacted, 2631 (27.5%) responded and 2143 (21.0%) were included in the analysis. Data were also available from 1211 (56.6%) of their PCPs and 643 (37.0%) of their CTS. PRIMARY AND SECONDARY OUTCOME MEASURES: Interval lengths (days; primary), routes to diagnosis and symptoms (secondary). RESULTS: With the exception of Denmark (-49 days), in all other jurisdictions, the median adjusted total interval from symptom onset to treatment, for respondents diagnosed in 2012-2015, was similar to that of Wales (116 days). Denmark had shorter median adjusted primary care interval (-11 days) than Wales (20 days); Sweden had shorter (-20) and Manitoba longer (+40) median adjusted diagnostic intervals compared with Wales (45 days). Denmark (-13), Manitoba (-11), England (-9) and Northern Ireland (-4) had shorter median adjusted treatment intervals than Wales (43 days). The differences were greater for the 10% of patients who waited the longest. Based on overall trends, jurisdictions could be grouped into those with trends of reduced, longer and similar intervals to Wales. The proportion of patients diagnosed following presentation to the PCP ranged from 35% to 75%. CONCLUSION: There are differences between jurisdictions in interval to treatment, which are magnified in patients with lung cancer who wait the longest. The data could help jurisdictions develop more focused lung cancer policy and targeted clinical initiatives. Future analysis will explore if these differences in intervals impact on stage or survival
    corecore