The improved computation presented in this paper is aimed to optimize the neural networks learning process using Levenberg-Marquardt (LM) algorithm. Quasi-Hessian matrix and gradient vector are computed directly, without Jacobian matrix multiplication and storage. The memory limitation problem for LM training is solved. Considering the symmetry of quasi-Hessian matrix, only elements in its uppe...

Recent experiments on triangular lattice organic Mott insulators have found evidence for a two-dimensional 2D spin liquid in close proximity to the metal-insulator transition. A Gutzwiller wave function study of the triangular lattice Heisenberg model with a four-spin ring exchange term appropriate in this regime has found that the projected spinon Fermi sea state has a low variational energy. ...

Results are presented for spin-wave dispersions in geometrically frustrated stacked triangular antiferromagnets with a thin film or semi-infinite geometry having either zero, easy-plane, or easy-axis anisotropy. Surface effects on the equilibrium spin configurations and excitation spectrum are investigated for the case of antiferromagnetically coupled films, serving to extend previous results o...

A histogram-based method for quasi-static test of analog-to-digital converters has been proposed for standardization aims. The test exploits the use of small-amplitude triangular waves. Different signal offset values are used to fully stimulate the converter input range. The reduced amplitude and slope of the input triangular wave with respect to the converter range and slew rate, respectively,...

The electronic properties of heterojunction electron gases formed in GaN/AlGaN core/shell nanowires with hexagonal and triangular cross sections are studied theoretically. We show that at nanoscale dimensions, the nonpolar hexagonal system exhibits degenerate quasi-one-dimensional electron gases at the hexagon corners, which transition to a core-centered electron gas at lower doping. In contras...

Introducing a black hole's e ective temperature, we obtained an Honorable Mention in the 2012 Gravity Research Foundation Essay Competition interpreting black hole's quasi-normal modes naturally in terms of quantum levels. This permitted us to show that quantities which are fundamental to realize the underlying quantum gravity theory, like Bekenstein-Hawking entropy, its sub-leading corrections...

We investigate the spectral properties of a hole moving in a two-dimensional Hubbard model for strongly correlated t(2g) electrons. Although superexchange interactions are Ising-like, a quasi-one-dimensional coherent hole motion arises due to effective three-site terms. This mechanism is fundamentally different from the hole motion via quantum fluctuations in the conventional spin model with SU...

Nonlinear plate bending within Mindlin's strain gradient elasticity theory (SGT) is investigated by employing somewhat non-standard finite element methods. The main goal to compare the results provided geometrically nonlinear three-dimensional (3D) and Reissner–Mindlin theory, i.e., first-order shear deformation (FSDT), SGT. For 3D Green–Lagrange relations are adopted, while von Kármán strains ...

We present a polynomial-time algorithm for recognizing quasi-Meyniel graphs. A hole is a chordless cycle with at least four vertices. A cap is a cycle with at least 6ve vertices, with a single chord that forms a triangle with two edges of the cycle. A graph G is quasi-Meyniel if it contains no odd hole and for some x ∈ V (G), the chord of every cap in G has x as an endvertex. Our recognition al...

We study the calculation of quasi-bound states in nMOS inversion channels and their impact on direct tunneling currents through the dielectric layer. For typical device parameters, the gate leakage in inversion is dominated by this tunneling component. However, a strong inaccuracy arises, if the eigenvalues of the closed system are used for the quasi-bound state tunneling current. We propose si...