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Eigenvalue distributions of multi-channel radar systems can be used to predict the achievable detection performance for moving target indication. For sea data they additionally inform about the present sea state. In this paper airborne experiments with the commercially available radar system SlimSAR were performed to analyze the eigenvalue distributions of real and simulated data of land, sea and...
Developing a new sonar for side-scan imaging can be a complicated and expensive proposition. Sonar models and simulations can be used to alleviate some of the expense and time required for development by providing some early simulated imagery of proposed designs. This paper describes a modeling approach where inverse imaging techniques are applied in order to generate simulated stave-level sonar data...
Planning for oil spill response and other marine activities requires a keen understanding of the weather and other conditions that can be expected in a given area and in a given period of time. It also requires consideratios about how those conditions — wind, waves, visibility, sea ice, etc. — may challenge or preclude on-water operations. The response viability analysis methodology matches data from...
Evaporation duct is an anomalous atmospheric surface layer over the sea surface and has severe influence on the microwave propagation. The evaporation duct height, which implies the strength of the evaporation duct, is an important physical quantity. Based on National Centers for Environmental Prediction Climate Forecast System Reanalysis data and the evaporation duct model, high spatial resolution...
A coastal acoustic tomography (CAT) experiment was carried out using seven sets of CAT systems between September 6 to 9, 2009, in the Sanmen Bay region. Both assimilation and inversion of the data were used to reconstruct the current fields. The assimilated velocities agreed better with the independent acoustic Doppler current profiler (ADCP) data than the velocities obtained through inversion. Root...
Alaska's Kenai fisheries are managed for maximum efficiency while ensuring fair allocation across multiple stakeholder groups and long term sustainability of the fishery. Managers must work to meet the fishery's goals while adapting their commercial and subsistence eco-service management practices to meet changing ecological conditions. Pre- and in-season fishery management practices are supported...
In this work we develop and demonstrate a probabilistic generative model for phytoplankton communities. The proposed model takes counts of a set of phytoplankton taxa in a timeseries as its training data, and models communities by learning sparse co-occurrence structure between the taxa. Our model is probabilistic, where communities are represented by probability distributions over the species, and...
Alaska's coastal communities are facing increased coastal hazards. Accurate predictive models are necessary to anticipate how various hazards may affect communities over time. Currently, erosion projections do not take into account the non-linear increase in erosion due to warming near-shore water, air, and permafrost. University of Alaska, Anchorage (UAA) is developing an arctic-capable coastal geomorphic...
Wave power potential assessment in the Indian Ocean along the South Coast of Central Java Island in Indonesia was conducted using 15-year hindcasting procedure through MIKE 21 Spectral Wave Software. A set of wind data with 0.125° spatial resolution and bathymetry were used to construct the model. The model was validated with experimental data from a observation buoy provided by the Agency for the...
Arctic coastal morphology is increasingly affected by changes to the climate. As the season length for shorefast ice decreases and temperatures warm permafrost, coastlines are increasingly susceptible to erosion from storm waves. Such coastal erosion is significant since the majority of the population centers and infrastructure in the Arctic are located near the coasts. Stakeholders and decision makers...
All commercial fishery species harvested globally either live on or near the seabed (also referred to as the benthos or benthic environment) or employ life history strategies or behaviors linked to benthic processes. The act of pursuing and catching benthic and demersal species requires operating fishing gear on or very near the seabed, resulting in direct gear-seabed contact. It is essential to further...
Explosive naval mines pose a threat to ocean and sea faring vessels, both military and civilian. This work applies deep neural network (DNN) methods to the problem of detecting minelike objects (MLO) on the seafloor in side-scan sonar imagery. We explored how the DNN depth, memory requirements, calculation requirements, and training data distribution affect detection efficacy. A visualization technique...
In order to improve the robustness of Adaptive Matched Field Processing(AMFP), a Conditional Probability Constraint Matched Field Processing (MFP-CPC) is proposed. The algorithm derives the posterior probability density of the source locations from Bayesian Criterion, then the main lobe of AMFP is protected and the side lobe is restricted by the posterior probability density, so MFP-CPC not only has...
This study investigates near-shore circulation and wave characteristics applied to a case-study site in Monterey Bay, California. We integrate physics-based models to resolve wave conditions (based on inputs from a global wave model, wind data from an operational weather platform, and predictions from a regional flow model) together with a linear machine learning algorithm that combines forecasts...
Mechanical systems operating in noisy environments create a challenging signal processing and monitoring problem especially in real-time. To detect a particular type of subsystem from noisy vibration data, it is necessary to identify signatures or particular features that make it unique. Resonant (modal) frequencies emitted during its normal operation satisfy this constraint. Monitoring structural...
Modeling the spatial variation of resources is necessary because it gives an estimate of what to expect during their exploration and exploitation. We focus on the spatial modeling of polymetallic nodules found in the deep sea regions of the Clarion-Clipperton zone in the Pacific. The data from this region available in the open domain is sparse, which warrants modeling techniques that can efficiently...
Focusing on detection technology for autonomous underwater detection device which found marine target which radiated noise signal submerged in background noise, chaotic detector based on Duffing oscillator is researched. In this paper, the Duffing oscillator and chaotic detector based on Duffing oscillator are described. Through numerical simulation and theoretical analysis, it is proved that the...
Terrestrial sensor systems and platforms regularly rely on photovoltaic cells as their primary power source. With a rechargeable battery backup, solar modules provide these remote sensor systems with reliable, simple, and predictable power. For these terrestrial systems, power predictions are well established and engineers developing power budgets have multiple avenues for estimating daily average...
Shell Exploration & Production Company is working with academic, non-profit, and federal stakeholders in the Gulf of Mexico to develop and implement long term environmental offshore monitoring programs. One such program, started in 2008 between Shell and the National Oceanic and Atmospheric Administration, has expanded to include new collaborators working together to operate multiple underwater...
Considering the cultural background of users is known to improve recommender systems for multimedia items. In this work, we focus on music and analyze user demographics and music listening events in a large corpus (120,000 users, 109 events) from Last.fm to investigate whether similarity between countries in terms of cultural and socio-economic factors is reflected in music taste. To this end, we...
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