Results 41 to 50 of about 12,874,811 (378)
Low-Density Parity-Check Codes
, 2004 Low-density parity-check (LDPC) error correcting codes were introduced in 1963 by Robert Gallager in his Ph.D. thesis. The basic motivation came from the observation that random linear codes, cf.
Christian Schlegel, Lance C. Perez
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Restoring the density-gradient expansion for exchange in solids and surfaces. [PDF]
Physical Review Letters, 2007 Popular modern generalized gradient approximations are biased toward the description of free-atom energies. Restoration of the first-principles gradient expansion for exchange over a wide range of density gradients eliminates this bias.
J. Perdew +7 more
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The Journal of Symbolic Logic, 2021 AbstractWe define a new type of “shatter function” for set systems that satisfies a Sauer–Shelah type dichotomy, but whose polynomial-growth case is governed by Shelah’s two-rank instead of VC dimension. We identify the least exponent bounding the rate of growth of the shatter function, the quantity analogous to VC density, with Shelah’s $\omega ...
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On Estimation of a Probability Density Function and Mode
, 1962 : Given a sequence of independent identically distributed random variables with a common probability density function, the problem of the estimation of a probability density function and of determining the mode of a probability function are discussed ...
E. Parzen
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Screening in orbital-density-dependent functionals
, 2017 Electronic-structure functionals that include screening effects, such as Hubbard or Koopmans' functionals, require to describe the response of a system to the fractional addition or removal of an electron from an orbital or a manifold. Here, we present a
Colonna, Nicola +3 more
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Mammographic density. Measurement of mammographic density [PDF]
Breast Cancer Research, 2008 Mammographic density has been strongly associated with increased risk of breast cancer. Furthermore, density is inversely correlated with the accuracy of mammography and, therefore, a measurement of density conveys information about the difficulty of detecting cancer in a mammogram.
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Self-interaction correction to density-functional approximations for many-electron systems
, 1981 exchange and correlation, are not. We present two related methods for the self-interaction correction (SIC) of any density functional for the energy; correction of the self-consistent one-electron potenial follows naturally from the variational principle.
J. Perdew, A. Zunger
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Bioinform., 2003 MOTIVATION When running experiments that involve multiple high density oligonucleotide arrays, it is important to remove sources of variation between arrays of non-biological origin. Normalization is a process for reducing this variation. It is common to
B. Bolstad +3 more
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Hormonal determinants of mammographic density and density change [PDF]
Breast Cancer Research, 2020 AbstractBackgroundMammographic density (MD) is a strong risk factor for breast cancer. We examined how endogenous plasma hormones are associated with average MD area (cm2) and annual MD change (cm2/year).MethodsThis study within the prospective KARMA cohort included analyses of plasma hormones of 1040 women.
Marike Gabrielson +9 more
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