It is proven that the lowest excitations Elow(k) of one-dimensional halfinteger spin generalized Heisenberg models and half-filled extended Hubbard models are π-periodic functions. For Hubbard models at fractional fillings Elow(k + 2kf ) = Elow(k), where 2kf = πn, and n is the number of electrons per unit cell. Moreover, if one of the ground states of the system is magnetic in the thermodynamic...

in this paper a new isolating system is introduced for short to mid-rise buildings. in comparison to conventional systems such as lrb and hrb, the proposed system has the advantage of no need to cutting edge technology and has low manufacturing cost. this system is made up of two orthogonal pairs of pillow-shaped rollers that are located between flat bed and plates. by using this system in two ...

large capacity cylindrical tanks are used to store a variety of liquids. their satisfactoryperformance during earthquake is crucial for modern facilities. in present paper, the behavior of cylindricalconcrete tanks under harmonic excitation is studied using the finite element method. liquid sloshing, liquidviscosity and wall flexibility are considered and additionally excitation frequency, liqu...

Sample controllers for a three-dimensional smart base-isolated building benchmark problem with linear and frictional isolation system are presented in this paper. A Kalman filter is used to estimate the states based on absolute acceleration measurements. Input filters are used to better inform the controller of the spectral content of the earthquake excitations. A reduced order control-oriented...

The low-frequency electronic excitations in double-walled armchair carbon nanotubes are studied within the random-phase approximation. The intertube atomic overlaps significantly affect the low-energy bands and thus enrich the low-frequency single-particle excitations and collective excitations. They induce more plasmon modes, reduce the plasmon strength, and change acoustic plasmons into optic...

We define and study holelike excitations (the Lieb II mode) in a weakly interacting Bose liquid subject to external confinement. These excitations are obtained by semiclassical quantization of gray solitons propagating on top of a Thomas-Fermi background. Radiation of phonons by an accelerated gray soliton leads to a finite lifetime of these excitations. It is shown that, for a large number of ...

We derive conservation laws from interactions of actively-interacting braid-like excitations of embedded framed spin networks in Quantum Gravity. Additionally we demonstrate that actively-interacting braid-like excitations interact in such a way that the product of interactions involving two actively-interacting braid-like excitations produces a resulting actively-interacting form. ∗Email addre...