1,213 research outputs found

    Rise-time effects in ggnMOSt under TLP stress

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    In this paper the main mechanisms that lead the turn on of the parasitic bipolar transistor of a grounded gate nMOS transistor (ggnMOS) under TLP stress have been analyzed in detail in the sub-nanoseconds range by means of a mixed-mode simulator. We showed that the breakdown voltage of the ggnMOS measured in static conditions would underestimate the maximum voltage across the protection structure obtained by TLP stress, depending on the rise-time of the applied puls

    Turn-on speed of grounded gate NMOS ESD protection transistors

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    The turn-on speed of nMOS transistors (nMOST) is of paramount importance for robust Charged Device Model (CDM) protection circuitry. In this paper the nMOST turn-on time has been measured for the first time in the sub-halve nanosecond range with a commercial e-beam tester. The method may be used to improve CDM-ESD hardness by investigating the CDM pulse responses within circuit. Furthermore it is shown that the CDM results of various protection layouts can be simulated with a SPICE model

    Who should pay for interdependent risk? Policy implications for security interdependence among airports

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    We study interdependent risks in security, and shed light on the economic and policy implications of increasing security interdependence in presence of reactive attackers. We investigate the impact of potential public policy arrangements on the security of a group of interdependent organizations, namely, airports. Focusing on security expenditures and costs to society, as assessed by a social planner, to individual airports and to attackers, we first develop a game‐theoretic framework, and derive explicit Nash equilibrium and socially optimal solutions in the airports network. We then conduct numerical experiments mirroring real‐world cyber scenarios, to assess how a change in interdependence impact the airports' security expenditures, the overall expected costs to society, and the fairness of security financing. Our study provides insights on the economic and policy implications for the United States, Europe, and Asia

    On the Impact of the Global Financial Crisis on the Euro Area

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    This paper analyses the impact of the Global Financial Crisis on the Euro area utilizing a simple dynamic macroeconomic model with interaction between monetary policy and �fiscal policy. The model consists of an IS curve, a Phillips curve, a term structure relation, a debt accumulation equation and a Taylor monetary policy rule supplemented with a Zero Lower Bound, and a fi�scal policy rule. The model is calibrated/estimated for EU-16 countries for the period 1980Q1{2009Q4. The impact of the Global Financial Crisis is studied by means of impulse responses following a combined, prolonged aggregate demand and public debt shock. The simulation mimicking the GFC turns out to work fairly well. However, the required size of the shock is quite large

    Photoemission spectroscopy and sum rules in dilute electron-phonon systems

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    A family of exact sum rules for the one-polaron spectral function in the low-density limit is derived. An algorithm to calculate energy moments of arbitrary order of the spectral function is presented. Explicit expressions are given for the first two moments of a model with general electron-phonon interaction, and for the first four moments of the Holstein polaron. The sum rules are linked to experiments on momentum-resolved photoemission spectroscopy. The bare electronic dispersion and the electron-phonon coupling constant can be extracted from the first and second moments of spectrum. The sum rules could serve as constraints in analytical and numerical studies of electron-phonon models.Comment: 4 page

    Instability due to long range Coulomb interaction in a liquid of polarizable particles (polarons, etc.)

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    The interaction Hamiltonian for a system of polarons a la Feynman in the presence of long range Coulomb interaction is derived and the dielectric function is computed in mean field. For large enough concentration a liquid of such particles becomes unstable. The onset of the instability is signaled by the softening of a collective optical mode in which all electrons oscillate in phase in their respective self-trapping potential. We associate the instability with a metallization of the system. Optical experiments in slightly doped cuprates and doped nickelates are analyzed within this theory. We discuss why doped cuprates matallize whereas nickelates do not.Comment: 5 pages,1 figur

    Process Qualification Strategy for Advances Embedded Non Volatile Memory Technology:The Philips' 0.18um Embedded Flash Case

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    A qualification strategy for advanced embedded non-volatile memory technology has been revealed. This strategy consists of: a thorough understanding of the requirements, extensive use and frequent update of the FMEA (failure mode effect analysis), a qualification plan with excellent coverage of all the risk areas, implementing effective in-line and off-line measures and control, and check-off of all the tests with good results. With such a strategy in place, the Philips 0.18 /spl mu/m embedded flash technology has been successfully qualified for volume production

    Monitoring 2009 Forest Disturbance Across the Conterminous United States, Based on Near-Real Time and Historical MODIS 250 Meter NDVI Products

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    This case study shows the promise of computing current season forest disturbance detection products at regional to CONUS scales. Use of the eMODIS expedited product enabled a NRT CONUS forest disturbance detection product, a requirement for an eventual, operational forest threat EWS. The 2009 classification product from this study can be used to quantify the areal extent of forest disturbance across CONUS, although a quantitative accuracy assessment still needs to be completed. However, the results would not include disturbances that occurred after July 27, such as the Station Fire. While not shown here, the project also produced maximum NDVI products for the June 10-July 27 period of each year of the 2000-2009 time frame. These products could be applied to compute forest change products on an annual basis. GIS could then be used to assess disturbance persistence. Such follow-on work could lead to attribution of year in which a disturbance occurred. These products (e.g., Figures 6 and 7) may also be useful for assessing forest change associated with climate change, such as carbon losses from bark beetle-induced forest mortality in the Western United States. Other MODIS phenological products are being assessed for aiding forest monitoring needs of the EWS, including cumulative NDVI products (Figure 10)
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