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Abstrak :
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.

Abstrak :
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.

Abstrak :
Digital sonar design in underwater acoustics principles and applications, provides comprehensive and up-to-date coverage of research on sonar design, including the basic theory and techniques of digital signal processing, basic concept of information theory, ocean acoustics, underwater acoustic signal propagation theory, and underwater signal processing theory. This book discusses the general design procedure and approaches to implementation, the design method, system simulation theory and techniques, sonar tests in the laboratory, lake and sea, and practical validation criteria and methods for digital sonar design. ;

Abstrak :
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.

Abstrak :
Shallow water acoustics (SWA), the study of how low and medium frequency sound propagates and scatters on the continental shelves of the worlds oceans, has both technical interest and a large number of practical applications. Technically, shallow water poses an interesting medium for the study of acoustic scattering, inverse theory, and propagation physics in a complicated oceanic waveguide. Practically, shallow water acoustics has interest for geophysical exploration, marine mammal studies, and naval applications. Additionally, one notes the very interdisciplinary nature of shallow water acoustics, including acoustical physics, physical oceanography, marine geology, and marine biology. In this specialized volume the authors, all of whom have extensive at-sea experience in US and Russian research efforts, have tried to summarize the main experimental, theoretical, and computational results in shallow water acoustics, with an emphasis on providing physical insight into the topics presented.

Abstrak :
ABSTRACT
Seorang karyawan memerlukan ruang kerja yang dapat mendukung aktivitas kerjanya. Kenyamanan ruang kerja adalah salah satu hal yang harus terpenuhi. Salah satu hal yang memengaruhi kenyamanan dari sebuah ruang kerja adalah ruang yang tenang, yaitu tidak ada suara bising yang mengganggu ketenangan para karyawan. Menurut Kepmenaker NOMOR : KEP.51/MEN/1999 , kebisingan adalah semua suara yang tidak dikehendaki yang bersumber dari alat-alat proses produksi dan atau alat-alat kerja yang pada tingkat tertentu dapat menimbulkan gangguan pendengaran pasal 1, no.10 . Pada zaman sekarang banyak tempat bekerja yang di dalamnya memiliki berbagai jenis pekerjaan, yaitu pekerjaan bising dan tenang. Kedua jenis pekerjaan ini memang saling terkait dimana dibutuhkan kolaborasi dan interaksi antar para karyawannya agar dapat menghasilkan pekerjaan yang optimal. Penempatan kedua ruang secara berdekatan menjadi solusi untuk memudahkan interaksi para karyawannya. Namun, akan menimbulkan polusi suara yang dihasilkan pekerjaan bising terhadap pekerjaan tenang. Hal ini akan berpengaruh pada kinerja, konsentrasi, komunikasi serta merusak sistem pendengaran para karyawan lainnya, terlebih jika material ruang tersebut bersifat memantulkan suara.

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ABSTRACT
An employee needs a workspace that can support his work activities. Working room comfort is one of the things that must be fulfilled. One of the things that affects the comfort of a work space is a quiet room, which is no noise that disturbs the quietness of the employees. According to Kepmenaker NOMOR KEP.51 MEN 1999 , noise is any undesirable sound sourced from the means of production processes and or work tools which at some level may cause hearing loss pasal 1, no.10 . Today, there are many workplaces in which there are various types of jobs, which are noisy and quiet jobs. Both types of work are indeed interrelated where it takes collaboration and interaction among its workers in order to produce optimal work. Placing the two working spaces close together becomes the solution to facilitate the interaction of the workers. However, it will cause noise pollution resulting in noisy work against quiet work. This will affect performance, concentration, communication and damage the hearing system of other workers, especially if the space material is reflective.