35,650 research outputs found
Volume integrals associated with the inhomegeneous Helmholtz equation. Part 2: Cylindrical region; rectangular region
Results are presented for volume integrals associated with the Helmholtz operator, nabla(2) + alpha(2), for the cases of a finite cylindrical region and a region of rectangular parallelepiped. By using appropriate Taylor series expansions and multinomial theorem, these volume integrals are obtained in series form for regions r r' and r 4', where r and r' are distances from the origin to the point of observation and source, respectively. When the wave number approaches zero, the results reduce directly to the potentials of variable densities
Effect of Decoherence on the Dynamics of Bose-Einstein Condensates in a Double-well Potential
We study the dynamics of a Bose-Einstein condensate in a double-well
potential in the mean-field approximation. Decoherence effects are considered
by analyzing the couplings of the condensate to environments. Two kinds of
coupling are taken into account. With the first kind of coupling dominated, the
decoherence can enhance the self-trapping by increasing the damping of the
oscillations in the dynamics, while the decoherence from the second kind of
condensate-environment coupling leads to spoiling of the quantum tunneling and
self-trapping.Comment: for color figures, see PR
Influence of additional stress caused by mining subsidence on blast furnace in metallurgical mining area
Underground goaf in metallurgical mining area leads to surface subsidence and has destructive effect on blast furnace. This paper studies the influence of underground goaf on blast furnace.The overlying strata and surface subsidence due to the formed gob area after the underground mining led to a different degree of destruction to blast furnace. Hence, blast furnace was modeled to theoretically analyze the additional stress applied to blast furnace body and foundation when withstanding the surface deformation. On this basis, the anti-deformation structure was designed to analyze the influences of Class I - IN surface deformation on the setting of Blast furnace body unit
On the Dichotomy between the Nodal and Antinodal Excitations in High-temperature Superconductors
Angle-resolved photoemission data on optimally- and under-doped high
temperature superconductors reveal a dichotomy between the nodal and antinodal
electronic excitations. In this paper we propose an explanation of this unusual
phenomenon by employing the coupling between the quasiparticle and the
commensurate/incommensurate magnetic excitations.Comment: 11 pages, 9 figure
Phenomenological and mechanics aspects of nondestructive evaluation and characterization by sound and ultrasound of material and fracture properties
Developments in fracture mechanics and elastic wave theory enhance the understanding of many physical phenomena in a mathematical context. Available literature in the material, and fracture characterization by NDT, and the related mathematical methods in mechanics that provide fundamental underlying principles for its interpretation and evaluation are reviewed. Information on the energy release mechanism of defects and the interaction of microstructures within the material is basic in the formulation of the mechanics problems that supply guidance for nondestructive evaluation (NDE)
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