Impedance boundary conditions for pseudo-spectral time-domain methods in room acoustics

The pseudo-spectral time-domain (PSTD) method is an alternative time-marching method to classicalleapfrog finite difference schemes in the simulation of wave-like propagating phenomena. It is basedon the fundamentals of the Fourier transform to compute the spatial derivatives of hyperbolic differential equations. Therefore, it results in an isotropic operator that can be implemented in an efficient way for room acoustics simulations. However, one of the first issues to be solved consists on modeling wallabsorption. Unfortunately, there are no references in the technical literature concerning to that problem. In this paper, assuming real and constant locally reacting impedances, several proposals to overcome this problem are presented, validated and compared to analytical solutions in different scenarios.

Impedance boundary conditions for pseudo-spectral time-domain methods in room acoustics

The Pseudo-Spectral Time Domain (PSTD) method is an alternative time-marching method to classical leapfrog finite difference schemes inthe simulation of wave-like propagating phenomena. It is based on the fundamentals of the Fourier transform to compute the spatial derivativesof hyperbolic differential equations. Therefore, it results in an isotropic operator that can be implemented in an efficient way for room acousticssimulations. However, one of the first issues to be solved consists on modeling wall absorption. Unfortunately, there are no references in thetechnical literature concerning to that problem. In this paper, assuming real and constant locally reacting impedances, several proposals toovercome this problem are presented, validated and compared to analytical solutions in different scenarios.

Condition of Employment, 2003

For much of American economic history, strength and manual dexterity could assure both a job and a reasonably comfortable standard of living. This is no longer the case as the industrial structure of American society has moved from agricultural to manufacturing to a service-producing economy. Today, we are changing the way we look at industries, jobs and, by extension, our economy. One of the responsibilities of Iowa Workforce Development is to study and report on those aspects of the economy that affect the working lives of Iowans – jobs, industrial employment, wages, and occupations. Condition of Employment 2003 is one of the vehicles we use to describe trends in the Iowa economy and the Iowa workplace.

Condition of Education in Iowa The Future for Education in Iowa, 2005

Statistics about public education in the state of Iowa including graduation rates and No Child Left Behind Act.

Female stereotypes in household appliances advertising and their social role in Spain: the perpetuation of a no- longer-existing female condition

The following dissertation proposes a qualitative approach on the matter ofadvertising, society and construction of identity, based on the effect of householdappliances commercials in constructing female identity of Spanish women today.Conclusions will be drawn based on a juxtaposition of social background andadvertising content and on how Spanish women of today perceive the evolution offemale imagery depicted in advertisements. The aim is to demonstrate how muchcommercials mirrors society and how far it reinforces paradigms no longer existing

Ordonnance de reglement pour les chasses (rendue par Louis Bontemps, capitaine des chasses de la varenne du Louvre) ... portant défenses à toutes personnes de quelque qualité et condition qu'elles soient, de chasser pendant deux années dans l'étendue de la capitainerie de la varenne du Louvre

[Acte. 1726-08-29. Paris]

The Annual Condition of Education Report, 2000

Statistics about public edcuation in the state of Iowa including graduation rates, No Child Left Behind Act,

The Annual Condition of Education Report, 1998

Statistics about public edcuation in the state of Iowa including graduation rates, No Child Left Behind Act,

The Annual Condition of Education Report, 1999

Statistics about public edcuation in the state of Iowa including graduation rates, No Child Left Behind Act,