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131.
132.
Interconnect imperfections have become an important issue in modern nanometer technologies. Some of them cause Small Delay Defects (SDDs) which are difficult to detect. Those SDDs not detected during testing may pose a reliability problem. Furthermore,
nanometer issues (e.g. process variations, spatial correlations) represent important challenges for traditional delay test
methods. In this paper, a methodology to compute the Detection Probability (DP) of resistive open and bridge defects using a statistical timing framework that takes into account process
variations and other nanometer issues is proposed. The DP gives the sensitivity of the circuit performance to a given resistance
range of the defect. The efficiency issue when analyzing large circuits is alleviated using stratified sampling techniques
to reduce the space of possible analyzed defect locations This methodology is applied to some ISCAS benchmark circuits. The
obtained results show the feasibility of the proposed methodology. Measures can be taken for those circuits presenting non-acceptable
DP in order to improve the test quality. 相似文献
133.
134.
This paper focuses on the results of the national research of cyberbullying of Czech teachers, which was realized in year 2016 in the entire Czech Republic. The research focused on impact of cyberbullying on teachers – especially in emotional, physiological and behavioural area. The research involved a total of 5136 primary and secondary school teachers from all regions of the Czech Republic. The research has shown that a fifth of respondents (21.73%) has experienced a cyber-attack on their person, however cyberbullying during the last 12 months lasting over 1 week was confirmed only by 3.52% of the total number of respondents. 相似文献
135.
The Hg0.8Cd0.2Te type-conversion, Hg self-diffusion and interdiffusion processes are analyzed in the context of a first order reaction kinetics
approach. Sets of nonlinear, stiffly coupled continuity equations are presented which describe the underlying physics, and
their solutions model the observed macroscopic behavior. It is demonstrated that the Frenkel pair mechanism interactions dominated
by the cation sublattice, in conjunction with basic diffusive and drift properties of the ionized point defects, comprise
the basic processes which effect all macroscopic phenomena discussed. Existing experimental results are reviewed and apparent
discrepancies discussed. Use is made of the Stanford University mercury cadmium telluride process simulator to provide quantitative
and insightful examples of important results. 相似文献
136.
Helder Fleury Pinheiro Attílio José Giarola Carlos Leônidas da Silva Souza Sobrinho 《Journal of Infrared, Millimeter and Terahertz Waves》1995,16(11):1965-1975
The formulation is developed in the frequency domain and the finite difference method is used for the numerical solution of the scalar wave equation, written in terms of the transverse components of the magnetic field. As a result a conventional eigenvalue problem is obtained without the presence of spurious modes due to the implicit inclusion of the divergence of the magnetic field equal to zero. The formulation is developed to include biaxial anisotropic dielectrics with an index profile varying arbitrarily in the cross section of the waveguide under analysis. This formulation is then applied to the analysis of the influence on the dispersion characteristics of the dimensions of asymmetric coupled rectangular uniaxial anisotropic dielectric waveguides. As expected, the reduction of the height or the width of one of the rectangular dielectric waveguides causes the dispersion curves to move towards higher frequencies. 相似文献
137.
Luis E. Juanicó Fabián Rinalde Eduardo Taglialavore Marcelo Molina 《Journal of Electronic Materials》2013,42(7):1789-1795
This paper presents a new thermogenerator based on moderate-temperature (up to 175°C) BiTe modules available on the open market. Despite this handicap relative to commercial thermogenerators based on high-temperature proprietary-technology PbBi modules (up to 560°C), this new design may become economically competitive due to its innovative thermal sink. Our thermal sink is based on a free-convection water loop built with standard tubing and household hot-water radiators, leading to a more practical, modular design. So, the specific cost of about 55,000 USD/kW obtained for this 120-W prototype is improved to 33,000 USD/kW for a 1-kW unit, which represents about half the price of commercial thermogenerators. Moreover, considering recently launched BiTe modules (that withstand up to 320°C), our proposition could have an even more favorable outlook. 相似文献
138.
Thierry Guillemot Eric Pottier Joseph Saillard Jean-René Levrel Emmanuelle Lebreton 《电信纪事》1997,52(1-2):81-93
In high frequency thercs measurement of large target must be done at important distances, so the distance of measurement (Fraunhofer’s distance) R is given by R ≥ 2d2 /λ where d is the tranversal length of the target and λ the radiation wavelength. In this paper we present a method for target that are large relative to the curvature of the spherical wavefront and the curvature of the cylindrical wavefront. A two-dimensional analytical algorithm transforms the spherical wave (near-field) measurement into the desired plane wave (far-field) and a one-dimensionnal analytical algorithm transforms the cylindrical wave (near-field) measurement into the desired plane wave (far-field). We present some results on simulations and measurements. A comparison of one-dimensional and two-dimensional methods demonstrates the efficiency of the two dimensional methods. 相似文献
139.
Audio-visual and other multimedia services are seen as an important source of traffic for ATM networks. Due to the statistical multiplexing schemes used by ATM networks, cells are exposed to delays, jitters and losses. These phenomena affect the quality of the service provided to the video-based applications. In this paper, we introduce a set of control mechanisms at different levels of the protocol architecture. These mechanisms have been particularly tailored to better support MPEG-2-based video communications applications using ATM networks as their underlying transmission mechanism. We show that the use of errorconcealment mechanisms prove more effective when supplemented by a structured set of protocol mechanisms. We study the impact of cell losses on the quality of MPEG-2 video sequences and provide an evaluation of the quality of the decoded video as perceived by the end user. Our results demonstrate the effectiveness of the proposed protocol architecture in improving the quality of service provided to the video application. 相似文献
140.
Girault JM Kouamé D Ouahabi A Patat F 《IEEE transactions on bio-medical engineering》2000,47(11):1431-1439
Several studies have been carried out in the last twenty years on the characterization and detection of cerebral artery emboli. From the detection point of view, the existing methods are largely based on the classical Fourier analysis of which the well known limitations provide poor accuracy. This paper first recalls existing methods based on Fourier, Wigner-Ville and wavelet approaches. It then presents new emboli detection methods based on parametric signal processing approaches. The basic idea of these parametric methods is to compare the Doppler embolic signal to its autoregressive model. The detection principle consists in constructing a decision information which contains the signature of the micro-embolus being sought. The detection is finally evaluated using receiver operating characteristic (ROC) curves. Comparison between the new methods and classical approaches is performed using a realistic embolic signal simulation. Furthermore, to validate our theoretical study, we tested our new algorithms using in vivo signals. This comparison shows the significant inaccuracy of existing methods to detect micro-emboli. 相似文献