6,164 research outputs found
Parton Interpretation and Twist-4 Parton Distributions
Through explicit examples we show that twist-4 parton distributions have no
parton interpretation in the sense that parton or partons inside a hadron can
carry the momentum fraction of the hadron with or . The
studied twist-4 parton distributions of collinear factoization are
power-divergent for . The corresponding transverse momentum
dependent parton distributions have also
no parton interpretation. They are finite. The implications of our results
are discussed.Comment: 11 pages, 3 figure
Providing appropriate social support to prevention of depression for high-anxious sufferers
This is the author accepted manuscript. The final version is available from the publisher via the DOI in this recordNational Natural Science Foundation of ChinaFundamental Research Funds for the Central Universities, ChinaChina Postdoctoral Science FoundationFund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shaanxi Provinc
Passivity enforcement for descriptor systems via matrix pencil perturbation
Passivity is an important property of circuits and systems to guarantee stable global simulation. Nonetheless, nonpassive models may result from passive underlying structures due to numerical or measurement error/inaccuracy. A postprocessing passivity enforcement algorithm is therefore desirable to perturb the model to be passive under a controlled error. However, previous literature only reports such passivity enforcement algorithms for pole-residue models and regular systems (RSs). In this paper, passivity enforcement algorithms for descriptor systems (DSs, a superset of RSs) with possibly singular direct term (specifically, D+D T or I-DD T) are proposed. The proposed algorithms cover all kinds of state-space models (RSs or DSs, with direct terms being singular or nonsingular, in the immittance or scattering representation) and thus have a much wider application scope than existing algorithms. The passivity enforcement is reduced to two standard optimization problems that can be solved efficiently. The objective functions in both optimization problems are the error functions, hence perturbed models with adequate accuracy can be obtained. Numerical examples then verify the efficiency and robustness of the proposed algorithms. © 2012 IEEE.published_or_final_versio
Transient Analysis of Warm Electron Injection Programming of Double Gate SONOS Memories by means of Full Band Monte Carlo Simulation
In this paper we investigate "Warm Electron Injection" as a mechanism for NOR
programming of double-gate SONOS memories through 2D full band Monte Carlo
simulations. Warm electron injection is characterized by an applied VDS smaller
than 3.15 V, so that electrons cannot easily accumulate a kinetic energy larger
than the height of the Si/SiO2 barrier. We perform a time-dependent simulation
of the program operation where the local gate current density is computed with
a continuum-based method and is adiabatically separated from the 2D full Monte
Carlo simulation used for obtaining the electron distribution in the phase
space. In this way we are able to compute the time evolution of the charge
stored in the nitride and of the threshold voltages corresponding to forward
and reverse bias. We show that warm electron injection is a viable option for
NOR programming in order to reduce power supply, preserve reliability and CMOS
logic level compatibility. In addition, it provides a well localized charge,
offering interesting perspectives for multi-level and dual bit operation, even
in devices with negligible short channel effects
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