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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."

"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."

"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. ;"

"This book provides comprehensive coverage of the detection and processing of signals in underwater acoustics. Background material on active and passive sonar systems, underwater acoustics, and statistical signal processing makes the book a self-contained and valuable resource for graduate students, researchers, and active practitioners alike. Signal detection topics span a range of common signal types including signals of known form such as active sonar or communications signals; signals of unknown form, including passive sonar and narrowband signals; and transient signals such as marine mammal vocalizations. This text, along with its companion volume on beamforming, provides a thorough treatment of underwater acoustic signal processing that speaks to its authors broad experience in the field."

"Teknologi akustik bawah air merupakan gelombang suara yang digunakan untuk mendeteksi keberadaan benda di air yang rata-rata digunakan untuk kepentingan data rahasia untuk tujuan tertentu dan dimanfaatkan untuk kepentingan yang dianggap mengamankan keadaan air laut di sekitarnya. Gelombang suara akan mengenai obyek sebagai sasaran untuk diketahui posisi/letak di perairan dalam atau dangkal. Penelitian ini bertujuan untuk menguji pengaruh efektivitas teknologi akustik terhadap potensi pelanggaran kapal selam asing yang memasuki wilayah NKRI. Penelitian ini menggunakan metode kuantitatif dan dilaksanakan di Pusat Hidrografi dan Oseanografi TNI Angkatan Laut (Pushidrosal). Sampel penelitian adalah personel Pushidrosal sebanyak 76 orang yang memiliki kualifikasi Surveyor Hidrografi. Hipotesis penelitian adalah Terdapat pengaruh positif dan signifikan secara simultan efektivitas teknologi akustik terhadap potensi pelanggaran kapal selam asing. Pengumpulan data untuk variabel menggunakan metode kuesioner (angket) dengan skala Likert. Keabsahan data diperoleh melalui uji validitas dan reliabilitas. Pengujian persyaratan analisis menggunakan uji asumsi klasik yang meliputi uji normalitas, uji multikolinieritas, dan uji heterokedastisitas dengan menggunakan tool software SPSS 25. Hasil penelitian menunjukkan bahwa terdapat pengaruh positif dan signifikan antara variabel Efektivitas terhadap variabel potensi pelanggaran kapal selam dapat dijawab dengan melihat hasil dari t hitung > ttabel (1.763 > 1,666). Sehingga dapat membuktikan bahwa terdapat pengaruh yang positif dan signifikan antara efektivitas terhadap potensi pelanggaran kapal selam sebesar 26,7%. Besarnya pengaruh tersebut meskipun kecil namun menunjukkan bahwa faktor yang menjadi kriteria atau ukuran efektivitas mampu mempengaruhi potensi pelanggaran kapal selam dalam waktu tertentu."

"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. "