This paper evaluates the potential for remote mapping of river bathymetry by (1) examining the theoretical basis of a simple, ratio-based technique for retrieving depth information from passive optical image data; (2) performing radiative transfer simulations to quantify the effects of suspended sediment concentration, bottom reflectance, and water surface state; (3) assessing the accuracy of s...

Airbome Laser Bathymetry (ALB) is a technique primarily aimed at augmenting nautical chart production and bathymetric mapping capability in relatively shallow coastal waters. The potential of waterpenetrating airborne laser radar to provide cost effective characterization of underwater topography to depths as great as 50 meters, depending on water clarity, has triggered a number of research and...

Current high-resolution side scan and multibeam sonars produce very large data sets. However, conventional interferometry-based bathymetry algorithms underestimate the potential information of such soundings, generally because they use small baselines to avoid phase ambiguity. Moreover, these algorithms limit the triangulation capabilities of multibeam echosounders to the detection of one sampl...

background and objective: high-level gentamicin resistance (hlgr: mic ≥ 500 µg/ml) in enterococci is mediated by aminoglycoside modifying enzymes which is mainly encoded by aac(6′)-ie-aph(2′′)-ia gene. the aim of this study was to evaluate the frequency of   aac(6′)-ie-aph(2′′)-ia gene in clinical isolates of enterococcus facium and enterococcus faecalis collected from hospitals in northwest of...

Coastal development and urban planning are facing different issues including natural disasters extreme storm events. The ability to track forecast the evolution of physical characteristics coastal areas over time is an important factor in development, risk mitigation overall zone management. Traditional bathymetry measurements obtained using echo-sounding techniques which considered expensive n...

Side-look synthetic aperture sonar (SAS) can produce very high quality images of the seabed. The imagery generated by SAS sensors display the seafloor and associated textures, such as sand ripples or seagrass. The characterization of SAS imagery is important for applications such as the detection and classification of targets, seabed segmentation and classification, and others. In this paper, w...

The objectives of our studies in FY09 are to collect observations of currents, waves, and bathymetry on tidal flats, and to develop, test, and improve models for tidal-flat processes and for mud-induced dissipation of waves in shallow water. Specific goals relating to tidal flats are to: Investigate the relative importance to the circulation of riverine and tidal flows, and Estimate the bottom ...