In advance longwall mining, the safety of mine network, production rate, and consequently, economic conditions of a mine are dependent on the stability conditions of gate roadways. The gate roadway stability is a function of two important factors: 1) characteristics of the excavation damaged zone (EDZ) above the gate roadway and 2) loading effect due to the caving zone (CZ) above the longwall w...

presence of joints and fractures in rocks strongly influences the behavior of the rock mass by dividing the media into smaller units. these structures intensify the potential instability besides the development of sliding and rotational movements. the assumption of discontinuum media changes the whole analysis conditions in relation to the continuum analysis. acquisition of geometrical and stru...

In this article, we establish the existence and non-existence of solutions for quasilinear equations with nonlinear boundary conditions and indefinite weight. Our proofs are based on variational methods and their geometrical features. In addition, we prove that all the weak solutions are in C1,β(Ω) for some β ∈ (0, 1).

A concise derivation is given for a compact nonlinear equation which specifies possible 3D rotations of rigid objects, compatible with measurements of five object points in two views. The insight provided by direct geometrical interpretation of this equation = which contains ULLMAN's polar equation as a special case-may be exploited for attempts to categorize the set of possible solutions.

nonlinear analyses allow simulating, in a more realistic way, the behaviour of structuressubjected to several types of complex loading conditions such as earthquakes. however, it isrecognized that these analyses normally generate a considerable amount of results, a factorthat difficult its interpretation. over the last years, considerable progresses have been made instructural nonlinear behavio...

in this paper the reflection coefficient of electromagnetic wave incidence on the walls of the buildings and obstacles that occurs in mobile communication path was modified by solving the riccati nonlinear equations. for this purpose, the building walls are assumed inhomogeneous layers where their permittivity changes as function of the wall thickness. using this reflection coefficient, a new p...