Thesis (Ph. D.)--Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, the Woods Hole Oceanographic Institution), 2004. / Includes bibliographical references (v. 2, leaves 211-215). / In recent years the focus of passive detection and localization of submarines has moved from the deep ocean into the littoral regions. the problem of passive detection in these regions is complicated by strong multipath propagation with high transmission loss. Large aperture planar arrays have the potential to improve detection performance due to their high resolution and high gain, but are suceptible to two main performance degradation mechanisms: limited spatial coherence of signals and nonstationarity of high bearing rate interference sources common in littoral regions of strategic importance. This thesis presents subarray processing as a method of improving passive detection performance using such large arrays. This thesis develops statistical models for the detection of performance of three adaptive, sample-covariance-based subarray processing algorithms which incorporate the effects of limited spatial coherence as well as finite snapshot support. The performance of the optimum processor conditioned on known data coveriances is derived as well for comparison. These models are then used to compare subarray algorithms and partitioning schemes in a variety of interference environments using plane wave and matched-field propagation models. / (cont.) The analysis shows a tradeoff between the required adaptive degrees of freedom, snapshot support, and adaptive resolution. This thesis shows that for both plane-wave and matched-field processing, the Conventional-Then-Adaptive (CTA) algorithm optimizes this tradeoff most efficiently. Finally, a comparison of the CTA algorithm to beam-space adaptive processing shows that for moderate beam coverage, the subarray algorithm performs as well as or superior to the adaptive beamspace algorighm. / by Jennifer Anne Watson. / Ph.D.

Underwater communication within underwater sensor network is crucial for surveillance of coast and ocean areas. The aim of this report was to examine whether it is realistic to use the communication signal which is sent from one node to another as a sonar pulse, and in such case at what distances. To examine the problem, a system consisting of two nodes and one approaching target was simulated in Matlab. At first, the system tries to detect the target by using a generalized likelihood ratio test, which calculates the probability of a present target from the surrounding sounds. When a target is detected by a node, it estimates the bearing to the target by using beamforming and sends out a communication signal to the other node. The communication signal spreads out in the water, and bounces on the target before it is received by the second node. To calculate the distance, the second node decodes the signal to get the time difference, from which the distance is calculated. In the end, the target's position was estimated with a weighted least square estimator with measurements of the bearing and distance. The result shows that the distance to the target could be estimated with high precision in the given scenario, and that the width of the Cramér-Rao lower bound depends mainly on the variance of the beamforming algorithm. The maximum distance reached up to two kilometers but was mainly restricted by the detection algorithm. In conclusion, the result shows that the communication pulse can be used as a sonar pulse at the tested distances. However, the simulated scenario is a simplified version of the real world so more testing should be performed before a final conclusion can be made. / För övervakning av kust- och havsområden, vid exempelvis militära operationer eller för oceanografska observationer, används ofta ett undervattenssystem som är uppbyggt av flera noder som finns utplacerade på botten. Noderna lyssnar efter mål såsom ubåtar, fartyg etc, med syftet att kunna detektera och lokalisera dessa. Om en nod lyckas detektera ett mål så skickar den ut en akustisk kommunikationssignal till övriga noder i systemet. Målet med detta examensarbete var att undersöka om den kommunikationssignal som skickas mellan noderna också kan användas som en sonarpuls för att bestämma avståndet till målet, och därmed förbättra lokaliseringen av målets position. Under antagandet att kommunikationssignalen kan användas som sonarpuls, så undersöktes dessutom vid vilka avstånd mellan noden och målet som det var möjligt att använda signalen som sonarpuls. Resultatet visar att det är möjligt att använda kommunikationssignalen som en sonarpuls. Bäst funkar det på nära avstånd, då är den estimerade positionen i stort sett lika med det riktiga positionen. I takt med att avståndet till målet ökar så ökar även osäkerheten i vilken rikting målet befinner sig, estimeringen av avståndet höll sig däremot väldigt nära den faktiska distansen i alla simuleringar som gjordes. Simuleringen som gjordes var dock en förenkling av verkligheten, och flera av de störningsmoment som finns ute i naturen har inte tagits med i beräkningarna. För att undersöka detta så simulerades ett sensorsystem bestående av två noder tillsammans med ett mål som närmade sig noderna. Noderna försöker detektera målet genom att lyssna efter ljud som tillhör målet. Genom att mäta energinivåer i de ljudsignaler som noderna hör, så kan man utifrån sannolikhetslära bestämma hur troligt det är att det finns ett mål i närheten. När sannolikheten är tillräckligt hög säger man att ett mål detekterats. För att bestämma positionen så uppskattades målets riktning och avstånd i förhållande till noderna, som i sin tur användes för att beräkna målets position.

Atlantic Bluefin tuna (Thunnus thynnus) is a highly value specie that was endangered during the turn of the century by overfishing. Due to the massive resource exploitation, a recovery plan was implemented by the International Commission for the conservation of Atlantic Tunas (ICCAT). That plan enforces three major rules: to establish a fishing quota, to impose a closed fishing seasons and to fix minimum catching size (30kg). With the aim to control and improve as much as possible the fattening process turns necessary develop tools to help tuna ranchers. These tools will help them to improve tuna production efficiency in sea cages. Moreover, it is necessary the improvement of fishing quota control mechanisms. Acoustic techniques have been revealed as an efficient biomass control tool in aquaculture cages (mainly to salmon and gilthead sea bream). However, underwater acoustic methods (that are used to remote sensing of fish schools in free water) are not usually applied in sea cages. Nowadays, production control, in tuna fattening cages, has made either by manual sampling or by the use of stereoscopic cameras system. The former, it can cause damages to fishes and increases costs to ranchers. The latter, it is non-intrusive to tuna but it is affected by depth and water turbidity and it is limited by camera field of vision. A feasibility study of the use of acoustic techniques in tuna fattening cages to production control as well as to evaluate tuna behavior in captivity is presented In this thesis. Research and development of techniques together with experimental setups used are limited by tuna size and cage volume. General information about Bluefin tuna and their farming in sea cages is included in Chapter 2. In order to provide the necessary understanding of the field, Chapter 3 perform a progressive introduction of theoretical concepts in relation with underwater acoustic techniques linked with biomass estimation. To find out the tuna behavior inside the cages after being captured an experiment was carried out. Likewise, a second experiment was proposed to evaluate the response of tunas to certain anthropogenic sounds (as those produced by offshore wind turbine). The methodology and results of both studies presented are discussed in Chapter 4. Chapter 5 shows the feasibility of the use of acoustic techniques to evaluate "ex situ" dorsal target strength (TS). A relationship between dorsal aspect TS and tuna length was obtained. To perform it, four different tuna size in four separated sea cages were measured using two EK60 echosounders working at 120 and 200 kHz respectively. Using data from tuna slaughter on a farm, relations between the weight and the different dimensions of the tuna: length, maximum width and height have been looked for. Obtained expressions allow to calculate fattened tunas weight from the three tuna dimensions. Results are shown in Chapter 6. In order to expand the study carried out in Chapter 5, an experiment was proposed to determine the relationship between ventral TS and tuna size. In this case, measurements were carried out using acoustic and optic techniques in a new setup concept. A stereoscopic vision system synchronized with two echosounders (EK60) emitting at 120 and 200 kHz were used. With this setup, it is possible to know the value of the TS for a certain tuna that was recorded and measured with the cameras. As in the dorsal measures case, it was sought to know the applicability degree of combined technique in fattened tuna cages. This study and its results are presented in Chapter 7. Finally, in Chapter 8, a new method to counting tuna using acoustic techniques is presented. This method is intended to facilitate counting tuna during transfer process. The use of underwater acoustic techniques allows to automate tuna counting and to make it immune to water turbidity during transfers. To achieve it, a side scan sonar working 200 kHz was used. / El atún rojo (Thunnus thynnus) es una especie de alto valor económico que se vio amenazada en el cambio de siglo por la sobrepesca. Este hecho llevó a la Comisión Internacional para la Conservación del Atún Atlántico (ICCAT) , a establecer un Plan de recuperación cuyas tres ejes principales fueron: imponer un férreo sistema de cuotas de pesca, limitar los periodos en los que esta especie puede ser capturada y fijar una talla mínima de captura .Los productores, afectados por las restricciones impuestas a la captura necesitan de herramientas para el control del proceso de engrase que permitan mejorar la eficiencia de dicho proceso. Del mismo modo se precisa la mejora de las herramientas utilizadas para el control de la cuota pesquera asignada. El control de la biomasa en las jaulas de engrase de atunes se realiza, bien mediante muestreos manuales que pueden provocar daños a los peces y resultar costosos operacional y económicamente, o bien mediante el uso de sistemas de cámaras estereoscópicas, no invasivas con los peces, pero que se ven limitadas por el alcance del campo de visión de las cámaras, la profundidad y la turbiedad del agua. Las técnicas acústicas se han revelado como una herramienta eficiente para el control de la biomasa en jaulas de cría para otras especies de gran consumo, como la dorada o el salmón. En esta tesis se propone estudiar la viabilidad del uso de las técnicas acústicas para el control de los atunes en las jaulas de engrase, así como para la evaluación del comportamiento de los atunes cuando pasan de vivir en estado salvaje a estar confinados en jaulas marinas. El tamaño de los atunes, así como la forma y tamaño de las jaulas donde son engrasados, limita los estudios y las configuraciones de medida presentadas en el presente documento. En el Capítulo 2 se incluye información general sobre del atún rojo y sobre su engrase en cautividad. Seguidamente, en el Capítulo 3, se ofrecen los conceptos básicos y la formulación sobre acústica submarina para facilitar la comprensión del resto de capítulos. Se realizó un experimento con el objetivo de conocer cómo se comporta el atún rojo en cautividad y si dicho comportamiento se veía alterado cuando era sometido a estímulos sonoros externos de carácter antropogénico. La metodología y los resultados de este estudio se muestran en el Capítulo 4. En el Capítulo 5, se evalúa la idoneidad del uso de técnicas acústicas para establecer una relación entre el tamaño del atún rojo y el TS (a 120 y 200 kHz), cuando se realizan las medidas desde la superficie del mar y con los sensores orientados hacia el fondo (vista dorsal de los peces). A partir de datos provenientes del sacrifico de peces engrasados, se han buscado relaciones entre el peso y las dimensiones del atún rojo. De este modo se han obtenido expresiones que predicen el peso medio de los peces engrasados en una jaula a partir de su longitud, altura y anchura máxima. Dichas expresiones se muestran en el Capítulo 6. Haciendo uso de las técnicas acústicas combinadas con un sistema de visión estereoscópica, se ha estudiado la viabilidad de obtener relaciones entre la longitud del atún rojo y el TS (a 120 y 200 kHz) en jaulas de engrase desde el punto de vista ventral. Para ello, se dispusieron los equipos en el fondo de la jaula de engrase y se registraron los datos con todos los sensores sincronizados y mirando hacia la superficie. De este modo se pudo conocer el valor del TS de un pez determinado que es grabado con un sistema estereoscópico que nos facilitara datos sobre su longitud, anchura máxima y orientación respecto del transductor. Se presenta en el capítulo 8 un método para el conteo de atunes mediante técnicas acústicas usando un sonar de barrido lateral trabajando a 200 kHz. Esta técnica novedosa pretende facilitar el conteo de ejemplares durante los procesos de transferencia, automatizándolo en gran medida y haciéndolo inmune a la fa / La tonyina roja (Thunnus thynnus) és una espècie d'alt valor econòmic que es va veure amenaçada durant el canvi de segle per la sobrepesca. Este fet va portar a la Comissió Internacional per a la Conservació de la Tonyina Atlàntica (ICCAT), a establir un pla de recuperació que tenía com a eixos principals imposar un ferri sistema de quotes de pesca, limitar els períodes en què esta espècie pot ser capturada, a fixar una talla mínima de captura. Els productors, afectats per les restriccions imposades a la captura necessiten de ferramentes per al control del procés de engreixament que permeten millorar l'eficiència del procés. De la mateixa manera, es precisa la millora de les ferramentes utilitzades per al control de la quota pesquera assignada. El control de la biomassa en les gàbies d'engreixament de tonyines es realitza, bé per mitjà de mostrejos manuals que poden provocar danys als peixos i resultar costosos operacional i econòmicament, o bé per mitjà de l'ús de sistemes de càmeres estereoscòpiques no invasives amb els peixos, però que es veuen limitades per l'abast del camp de visió de les càmeres, la profunditat i la terbolesa de l'aigua. Les tècniques acústiques s'han revelat com una ferramenta eficient per al control de la biomassa en gàbies de cria per a altres espècies de gran consum com la daurada o el salmó. En esta tesi es proposa estudiar la viabilitat de l'ús de les tècniques acústiques per al control de les tonyines en les gàbies engreixament, així com per a l'avaluació del comportament de les tonyines quan passen de viure en estat salvatge, a estar confinades en gàbies marines. La grandària de les tonyines, així com la forma i grandària de les gàbies on són engreixades, limita els estudis i les configuracions de mesura presentades en este document. En el Capítol 2, s'inclou informació general sobre la tonyina roja i sobre el seu engreixament en captivitat. A continuació, en el Capítol 3, s'ofereixen els conceptes bàsics i la formulació sobre acústica submarina per a facilitar la comprensió de la resta de capítols. Es va realitzar un experiment amb l'objectiu de conèixer com es comportava la tonyina roja en captivitat, i si este comportament es veia alterat quan era sotmesa a estímuls sonors externs de caràcter antropogènic. La metodologia i els resultats d'este estudi es mostren en el Capítol 4. En el Capítol 5, s'avalua la idoneïtat de l'ús de tècniques acústiques per a establir una relació entre la grandària de la tonyina roja i el TS (a 120 i 200 kHz), quan es realitzen les mesures des de la superfície del mar i amb els sensors orientats cap al fons (vista dorsal dels peixos). A partir de dades provinents del sacrifici de peixos engreixats, s'han buscat relacions entre el pes i les dimensions de la tonyina roja. D'esta manera, s'han obtingut dades que prediuen el pes mitjà dels peixos engreixats en una gàbia a partir de la seua longitud, alçària i amplària màxima. Estes dades es mostren en el Capítol 6. Fent ús de les tècniques acústiques combinades amb un sistema de visió estereoscòpica, es va estudiar la viabilitat d'obtindre relacions entre la longitud de la tonyina roja i el TS (a 120 i 200 kHz) en gàbies d'engreixament des del punt de vista ventral. Per a això, es van disposar els equips en el fons de la gàbia marina i es van registrar les dades amb tots els sensors sincronitzats i mirant cap a la superfície. De aquesta manera, es va poder conèixer el valor del TS d'un peix determinat que és gravat amb un sistema estereoscòpic que ens facilitarà dades sobre la seua longitud, amplària màxima i orientació respecte del transductor. Finalment, en el Capítol 8, es presenta un mètode per al comptatge de tonyines per mitjà de tècniques acústiques fent ús d'un un sonar d'escombrat lateral treballant a 200 kHz . Esta tècnica nova pretén facilitar el comptatge d'exemplars durant els processos de transferència, au / Puig Pons, V. (2017). Control y caracterización del Atún Rojo en Jaulas Marinas [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/86213

The advancement of foundation models have opened up new possibilities in deep learning. These models can be adapted to new tasks and unseen domains from minimal or even no training data, making them well-suited for applications where labelled data is scarce or costly to collect. Lack of data has meant that deep learning for change detection in sonar imagery has not been used. Reliable methods for change detection of underwater environments is critical for a range of fields such as marine research and object search. Previous work in change detection for sonar imagery focus on non-deep learning methods. In this paper, we explore the use of a foundation model (Segment Anything Model) for performing change detection in imagery collected with synthetic aperture sonar (SAS). This thesis is the first case of applying Segment Anything Model to change detection in SAS imagery. The proposed method segments bi-temporal images, and change detection is then performed on the segments. In addition to a set of bi-temporal images containing real change, the model is also tested on a set of synthetic images. The proposed method shows promising results on both a real and synthetic data set.

International Telemetering Conference Proceedings / October 20-23, 2003 / Riviera Hotel and Convention Center, Las Vegas, Nevada / Disk Recorders now represent a high performance, low cost and reliable alternative to traditional tape recorders for a wide range of platform data recording applications. This paper discusses the latest advances in disk-based recording technology in the context of multi-channel Telemetry applications, showing the degree of flexibility that is now possible in terms of both channel count and the ability to record synchronous and asynchronous digital data streams alongside multiple wideband analog channels. The techniques described are equally applicable to Acoustic, SIGINT and Telecommunications data capture and analysis applications aboard static, airborne and maritime platforms. Topics covered include how new disk-based data capture technologies have been able to extend bandwidth, storage capacity, signal fidelity and the overall capability of mission recorders. Advanced operational issues, including true ‘read-after-write’, data security, portability and archiving, enhanced data management and analysis strategies are also covered. The Paper includes detailed test results from COTS Disk Recorders already in service as well as an informative Road Map for this exciting new technology.

Thesis (MScEng)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: In recent years Autonomous Underwater Vehicles (AUVs) have become interesting for harbor mapping and protection. AUVs require a SONAR sensor for observing their surroundings, thus enabling them to perform collision avoidance manoeuvres and scanning their operating environment for intruders or foreign objects, e.g. mines. To perform such actions the SONAR sensor is required to supply very fine range resolution for target imaging, as well as providing information about possible target velocity. Basic SONAR theory is discussed, as well as different approaches to signal design and processing techniques, for achieving the required resolution in range and target velocity. Two of the discussed approaches are selected for processing range and target velocity, respectively. Both approaches are simulated for their validity before being tested by using a custom-built platform. The platform is highly configurable and designed for capacity of testing a variety of SONAR signals and set ups. Furthermore, the platform is built by using off-the-shelf components to minimize development costs. The results of simulations and practical tests are presented. A high correlation between theory and practice is achieved. The knowledge and the platform presented form the stepping stone for further SONAR sensor developments. / AFRIKAANSE OPSOMMING: In die laaste jare het outonome onderwater voertuie (OOV) toenemend belangrik geword vir die kartografie en beskerming van hawens. OOV’s vereis SONAR sensore wat hulle in staat stel, om hulle omgewing waar te neem en sodoende botsing vermydings take te verrig en ook om hul werksomgewing noukeurig te skandeer om indringers of vreemde voorwerpe, bv. myne, op te spoor. Om sulke werk te verrig, word van die SONAR sensor vereis, om baie fyn afstand oplossings vir teiken te verskaf, insluitend die moontlike snelheid van die teiken. Basiese SONAR teorie word bespreek, en dan verskeie benaderings van sein ontwerp en verwerkings tegnieke. Twee van die bespreekte benaderings word gekies om afstand en teiken snelheid onderskeidelik te verwerk. Altwee benaderings word gesimuleer om hul geldigheid vas te stel, voor dat hulle getoets word op ’n pasmaat vervaardigde platform. Die platform is hoogs aanpasbaar en is ontwerp vir sy vermoë om ’n verskeidenheid SONAR seine en verwerkings te hanteer. Verder is die platform vervaardig met standard rakonderdele om ontwikkelingskoste so laag as moontlik te hou. Die uitslae van die simulerings en praktiese toetse word voorgestel. ’n Hoë mate aan korrelasie is bereik tussen teorie en praktyk. Die kennis en die platvorm, wat hier voorgestel word, vorm die eerste trappie vir toekomstige SONAR sensor ontwikkeling.

Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2009. / ENGLISH ABSTRACT: Sonars are used extensively for underwater sensing and recent advances in forward-looking imaging sonar have made this type of sonar an appropriate choice for use on Autonomous Underwater Vehicles. The images received from these sonar do however, tend to be noisy and when used in shallow water contain strong bottom reflections that obscure returns from actual targets. The focus of this work was the investigation and development of post-processing techniques to enable the successful use of the sonar images for automated navigation. The use of standard image processing techniques for noise reduction and background estimation, were evaluated on sonar images with varying amounts of noise, as well as on a set of images taken from an AUV in a harbour. The use of multiple background removal and noise reduction techniques on a single image was also investigated. To this end a performance measure was developed, based on the dynamic range found in the image and the uniformity of returned targets. This provided a means to quantitatively compare sets of post-processing techniques and identify the “optimal” processing. The resultant images showed great improvement in the visibility of target areas and the proposed techniques can significantly improve the chances of correct target extraction. / AFRIKAANSE OPSOMMING: Sonars word algemeen gebruik as onderwater sensors. Onlangse ontwikkelings in vooruit-kykende sonars, maak hierdie tipe sonar ’n goeie keuse vir die gebruik op ’n Outomatiese Onderwater Voertuig. Die beelde wat ontvang word vanaf hierdie sonar neig om egter raserig te wees, en wanneer dit in vlak water gebruik word toon dit sterk bodemrefleksies, wat die weerkaatsings van regte teikens verduister. Die fokus van die werk was die ondersoek en ontwikkeling van naverwerkings tegnieke, wat die sonar beelde bruikbaar maak vir outomatiese navigasie. Die gebruik van standaard beeldverwerkingstegnieke vir ruis-onderdrukking en agtergrond beraming, is geëvalueer aan die hand van sonar beelde met verskillende hoeveelhede ruis, asook aan die hand van ’n stel beelde wat in ’n hawe geneem is. Verdere ondersoek is ingestel na die gebruik van meer as een agtergrond beramings en ruis onderdrukking tegniek op ’n enkele beeld. Hierdie het gelei tot die ontwikkeling van ’n maatstaf vir werkverrigting van toegepaste tegnieke. Hierdie maatstaf gee ’n kwantitatiewe waardering van die verbetering op die oorspronklike beeld, en is gebaseer op die verbetering in dinamiese bereik in die beeld en die uniformiteit van die teiken se weerkaatsing. Hierdie maatstaf is gebruik vir die vergelyking van verskeie tegnieke, en identifisering van die “optimale” verwerking. Die verwerkte beelde het ’n groot verbetering getoon in die sigbaarheid van teikens, en die voorgestelde tegnieke kan ’n betekenisvolle bedrae lewer tot die suksesvolle identifisering van obstruksies.

Over the past decades technological developments have both changed and increased human in influence on the marine environment. We now have greater potential than ever before to introduce disturbance and deplete marine resources. Two of the issues currently under public scrutiny are the exploitation of fish stocks worldwide and levels of anthropogenic noise in the marine environment. The aim of this thesis is to investigate and develop novel analyses and simulations to provide additional insight into some of the challenges facing the marine ecosystem today. These methodologies will improve the management of these risks to marine ecosystems. This thesis first addresses the issue of competition between humans and grey seals (Halichoerus grypus) for marine resources, providing compelling evidence that a substantial proportion of the sandeels consumed by grey seals in the North Sea are in fact H. lanceolatus, which is not commercially exploited, rather than the commercially important A. marinus. In addition, we present quantitative results regarding sources of bias when estimating the total biomass of sandeels consumed by grey seals. Secondly, we investigate spatially adaptive 2-dimensional smoothing to improve the prediction of both the presence and density of marine species, information that is often key in the management of marine ecosystems. Particularly, we demonstrate the benefits of such methods in the prediction of sandeel occurrence. Lastly this thesis provides a quantitative assessment of the protocols for real-time monitoring of marine mammal presence, which require that acoustic operations cease when an animal is detected within a certain distance (i.e. the "monitoring zone") of the sound source. We assess monitoring zones of different sizes with regards to their effectiveness in reducing the risks of temporary and permanent damage to the animals' hearing, and demonstrate that a monitoring zone of 2 km is generally recommendable.

Approved for public release; distribution is unlimited / Reissued 30 May 2017 with correction to student's affiliation on title page. / Autonomous vehicle teams have great potential in a wide range of maritime sensing applications, including mine countermeasures (MCM). A key enabler for successfully employing autonomous vehicles in MCM missions is motion planning, a collection of algo-rithms for designing trajectories that vehicles must follow. For maximum utility, these algorithms must consider the capabilities and limitations of each team member. At a minimum, they should incorporate dynamic and operational constraints to ensure trajectories are feasible. Another goal is maximizing sensor performance in the presence of uncertainty. Optimal control provides a useful frame-work for solving these types of motion planning problems with dynamic constraints and di_x000B_erent performance objectives, but they usually require numerical solutions. Recent advances in numerical methods have produced a general mathematical and computational framework for numerically solving optimal control problems with parameter uncertainty—generalized optimal control (GenOC)— thus making it possible to numerically solve optimal search problems with multiple searcher, sensor, and target models. In this dissertation, we use the GenOC framework to solve motion planning problems for di_x000B_erentMCMsearch missions conducted by autonomous surface and underwater vehicles. Physics-based sonar detection models are developed for operationally relevant MCM sensors, and the resulting optimal search trajectories improve mine detection performance over conventional lawnmower survey patterns—especially under time or resource constraints. Simulation results highlight the flexibility of this approach for optimal mo-tion planning and pre-mission analysis. Finally, a novel application of this framework is presented to address inverse problems relating search performance to sensor design, team composition, and mission planning for MCM CONOPS development.

Small scale protected zones are valuable for helping the health and productivity of fisheries at Lake Tanganyika (East Africa). Spatial placement of protected areas relies on accurate maps of benthic habitats, consisting of detailed bathymetry data and information on lake-floor substrates. This information is unknown for most of Lake Tanganyika. Fish diversity is known to correlate with rocky substrates in ≤ 30 m water depth, which provide spawning grounds for littoral and pelagic species. These benthic habitats form important targets for protected areas, if they can be precisely located. At the NMVA, echosounding defined the position of the 30-m isobath and side-scan sonar successfully discriminated among crystalline basement, CaCO3-cemented sandstones, mixed sediment, and shell bed substrates. Total area encompassed from the shoreline to 30 m water depth is ~21 km2 and the distance to the 30-m isobath varies with proximity to deltas and rift-related faults. Total benthic area defined by crystalline basement is ~1.6 km2, whereas the total area of CaCO3-cemented sandstone is 0.2 km2. Crystalline basement was present in all water depths (0-30 m), whereas CaCO3-cemented sandstones were usually encountered in water ≤ 5 m deep. Spatial organization of rocky substrates is chiefly controlled by basin structure and lake level history.