Results 301 to 310 of about 3,357,696 (317)

Clusterability and Centroid Approximation

2003
Identifying clusters in a dataset is valuable. Most existing data clustering algorithms need the number of clusters as an input. The present paper introduces a graphical method that outputs the number of clusters. Once the number of clusters is calculated, other clustering algorithms may use it. This method is cubic in the number of input data.
Alina Romero, Mukkai S. Krishnamoorthy
openaire   +1 more source

Cluster approximations in alloys

physica status solidi (b), 1973
AbstractSeveral cluster approximations in alloys are discussed and numerically studied for the one‐dimensional tight‐binding model. The approximations are compared, and some interrelations are found to exist. The shortcomings of the cluster approximations such as broadening, shifting, and diminishing of various cluster bands are exhibited.
openaire   +1 more source

An approximate coupled cluster doubles polarization propagator approximation

International Journal of Quantum Chemistry, 1988
A polarization propagator method based upon an approximate coupled cluster doubles (ACCD) wavefunction is presented and applied to CH+ and Be in calculations of excitation energies and radiative lifetimes. It is found that in these cases the computational results are nearly identical to results obtained using a similar method based on the full coupled ...
openaire   +1 more source

Accurate thermochemistry from explicitly correlated distinguishable cluster approximation.

Journal of Chemical Physics, 2015
D. Kats, D. Kreplin, H. Werner, F. Manby
semanticscholar   +1 more source

A goal-oriented adaptive procedure for the quasi-continuum method with cluster approximation

Computational Mechanics, 2015
Arash Memarnahavandi, F. Larsson, K. Runesson   +2 more
semanticscholar   +1 more source

Landau potential of a KDP crystal in the cluster approximation of the pseudospin model

, 2012
V. A. Abalmassov, A. S. Yurkov
semanticscholar   +1 more source

Variational cluster approximation study of the one-dimensional Holstein-Hubbard model at half filling

, 2011
A. Payeur, D. Sénéchal
semanticscholar   +1 more source

Dielectric susceptibility of a deuterated KDP crystal from experiment on Raman scattering and in the cluster approximation

, 2011
V. A. Abalmassov, A. Pugachev, N. Surovtsev   +2 more
semanticscholar   +1 more source

Approximant cluster reduction

2007
openaire   +1 more source

Mean-field (n,m)-cluster approximation for lattice models.

Physical Review A. Atomic, Molecular, and Optical Physics, 1992
Daniel ben-Avraham, J. Kohler
semanticscholar   +1 more source