Selected Aspects of Meshless Method Optimization in the Room Acoustics with Impedance Boundary Conditions

Groups Generated by Wave-duct Acoustics with Impedance Boundary Conditions

Source-free wave-duct acoustics formulated as an initial value problem for the wave equation with impedance boundary conditions is considered. Properties of the corresponding C0-groups and their generators are given by emphasizing the spectral representation of these operators. Research supported in part (H.T.B.) by the Air Force O ce of Scienti c Research under grant AFOSR-90-0091. This resear...

Imposing boundary conditions in the meshless local Petrov–Galerkin method

A particular meshless method, named meshless local Petrov–Galerkin is investigated. To treat the essential boundary condition problem, an alternative approach is proposed. The basic idea is to merge the best features of two different methods of shape function generation: the moving least squares (MLS) and the radial basis functions with polynomial terms (RBFp). Whereas the MLS has lower computa...

Time Domain Boundary Element Method for Room Acoustics

the effect of taftan pozzolan on the compressive strength of concrete in the environmental conditions of oman sea (chabahar port)

cement is an essential ingredient in the concrete buildings. for production of cement considerable amount of fossil fuel and electrical energy is consumed. on the other hand for generating one tone of portland cement, nearly one ton of carbon dioxide is released. it shows that 7 percent of the total released carbon dioxide in the world relates to the cement industry. considering ecological issu...

A Collocation Method with Modified Equilibrium on Line Method for Imposition of Neumann and Robin Boundary Conditions in Acoustics (TECHNICAL NOTE)

A collocation method with the modified equilibrium on line method (ELM) forimposition of Neumann and Robin boundary conditions is presented for solving the two-dimensionalacoustical problems. In the modified ELM, the governing equations are integrated over the lines onthe Neumann (Robin) boundary instead of the Neumann (Robin) boundary condition equations. Inother words, integration domains are...