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"This book presents current research trends in the field of underwater acoustic wave direct and inverse problems. Until very recently, little has been published concerning model-based inversions of the boundaries and material constants of finite-sized targets located either in the water column or the sediments. This text is the first to investigate inverse problems in an ocean environment with a heavy emphasis placed on the description and resolution of the forward scattering problem.Marine Acoustics: Direct and Inverse Problems emphasizes computation of Green's Functions with new material added for elastic and poro-elastic seabeds. This timely publication addresses many areas of practical interest in connection with underwater acoustical imaging including ecological survey and clean up, protection of open water harbors, offshore petroleum and gas enterprises, as well as environmental and military uses. The ocean-seabed system is an acoustic waveguide and this is the only book that treats inverse problems in a waveguide. The propagation of acoustic waves in this system is treated for various types of seabeds and the direct and inverse problems are considered in realistic ocean environments. The inverse problem is to determine the shape of an impenetrable or penetrable object, or to determine the coefficients describing the seabed. This is done by acoustically illuminating the seabed and investigating the scattered field."

"This literature study presents an overview of underwater acoustic networking. It provides a background and describes the state of the art of all networking facets that are relevant for underwater applications. "

"In architectural acoustics, Cathedrals and Churches are usually give specific acoustic characteristics and their acoustic treatments therefore are relatively difficult. In the case of Jakarta, there is only one Cathedral that was built around 1890 with a Neo-Gothic style and now is still being used. The capacity of the Cathedral is for 800 people, it has been used for Catholic masses and sometimes for musical, choir, and chamber orchestra performances. The plan shape of the cathedral is cross with 60 m length, main width is JO m and 5 m for the aisles in each side. The height of the ceiling is 17 m. The electro-acoustic is used for the masses and performances, although it is said that it is not necessary. The acoustic attribute judged to the cathedral therefore should be assessed and evaluated, by investigating the behaviour of sound. This paper evaluates the acoustic properties of the cathedral in relation with its shape and dimensions. The surrounding materials used for the cathedral are also evaluated. The acoustic measurements involved are reverberation time. The derived acoustic parameters were then validated with the theoretical predictions. Besides, subjective predictions were used from several seating positions. The results obtained from the measurements indicated that the design of cathedral is appropriate regarding its RT for masses and choirs as well as the interior design for architectural point of view, and therefore the judgement for not using electro-acoustic is appropriate."