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Snow Cover Area monitoring is an important factor in studies of global climate change, regional water balance and soil moisture. Recently, the usage of remote sensing techniques has flourished. In fact, remote sensing data provides timely adequate snow cover information for large areas. While the National Center for Remote Sensing in Lebanon (CNRS) has recently established an operational monitoring room for natural resources and natural disasters, this paper presents the implementation of a fully automated snow cover monitoring system based on Moderate Resolution Imaging Spectroradiometer (MODIS) satellite images. The system uses snow products from EOS Terra, and Aqua satellites to monitor the Snow Cover of Lebanon during the snow season (i.e. November-April). The importance of this project lies in its daily and fully automated process of acquiring, processing, storing and displaying statistics of the snow covered areas in Lebanon. Applying a custom algorithm based on combining Terra and Aqua snow products will reduce cloud contamination.

Integrated full electric propulsion systems are being introduced across both civil and military marine sectors. Standard power system analysis packages cover electrical and electromagnetic components but have limited models of mechanical subsystems and their controllers. Hence, electromechanical system interactions between the prime movers, power network, and driven loads are poorly understood. This paper reviews available models of the propulsion drive system components: The power converter, motor, propeller, and ship. Due to the wide range of time constants in the system, reduced-order models of the power converter are required. A new model using state-averaged models of the inverter and a hybrid model of the rectifier is developed to give an effective solution combining accuracy with speed of simulation and an appropriate interface to the electrical network model. Simulation results for a typical ship maneuver are presented. © 2009 IEEE.

We present a method for restoring the recordings obtained from surveillance cameras whose quality deteriorates due to dirt or water that gathers on the camera's lens. The method is designed to operate in the surveillance setting and makes use of good quality frames from the beginning of the recorded sequence to remove the blur at later stages caused by the dirty lens. A background subtraction method allows us to obtain a stable background of the scene. Based on this background, a multiframe blind deconvolution algorithm is used to estimate the Point Spread Function (PSF) of the blur. Once the PSF is obtained it can be used to deblur the entire scene. This restoration method was tested on both synthetic and real data with improvements of 15 dB in PSNR being achieved by using clean frames from the beginning of the recorded sequence.

This study was conducted to determine the effect of detergents on eggs hatchability, survival rates, morphometry and bone structure of Wader Pari fish (Rasbora lateristriata Bleeker, 1854). The fish were treated with detergent solution, with a concentration of 0 mg L−1, 3 mg L−1, 6 mg L−1, 9 mg L−1, 18 mg L−1, 27 mg L−1, and 50 mg L−1, respectively. Each test consisted of one aquarium filled with 30 eggs. The number of eggs hatched was counted and these were treated continually for 1.5 mo to determine fish survival rates, morphology, growth rates and bone structure assays. The bone structure assay was prepared with Alizarin’s Red-Alcian Blue staining. The results show that detergent treatments at 0 mg L−1, 3 mg L−1, 6 mg L−1, 9 mg L−1 did not significantly affect hatchability, survival rate, or morphometry of either egg or fish (p > 0.05). However, a higher concentration at 18 mg L−1, 27 mg L−1, and 50 mg L−1, significantly affected the fish egg hatchability and survivability. Moreover, fish vertebral structures were normal at treatments of 0 mg L−1, 3 mg L−1, 6 mg L−1, whereas at 9 mg L−1, was caused abnormal vertebral structures.

We address the analysis of fish trajectories in unconstrained underwater videos environmental changes which can be observed from the abnormal behaviour of fish. The fish trajectories are separated into normal and abnormal classes which indicate the common behaviour of fish and the behaviours that are rare/ unusual respectively. The proposed solution is based on a novel type of hierarchical classifier which builds the tree using clustered and labelled data based on similarity of data while using different feature sets at different levels of hierarchy. The paper presents a new method for fish trajectory analysis which has better performance compared to state-of-the-art techniques while the results are significant considering the challenges of underwater environments, low video quality, erratic movement of fish and highly imbalanced trajectory data that we used. Moreover, the proposed method is also powerful enough to classify highly imbalanced real-world datasets.

The annotation of large datasets containing domain-specific images is both time-consuming and difficult. However, currently computer vision and machine learning methods have to deal with ever increasing amounts of data, where annotation of this data is essential. The annotated images allow these kind of methods to learn the variation in large datasets and evaluate methods based on large datasets. This paper presents a method for annotation of domain-specific (fish species) images using approximate nearest neighbor search to retrieve similar fish species in a large set (216,501) of images. The approximate nearest neighbor search allows us to find a ranked set of images in large datasets. Presenting similar images to users allows them to annotate images much more efficiently. In this case, our user interface present these images in such a way that the user does not need to have knowledge of a specific domain to contribute in the annotation of images.

By providing a common power supply to both the propulsion and service loads on ships, Integrated Full Electric Propulsion (IFEP) offers benefits of increased design flexibility and reduced running costs. Whilst presenting power system challenges commonly seen in land based grid systems, the prevalence of power electronics, high power density, and the significance of individual loads (such as propulsion drives) creates particular challenges for modelling and simulation tools. Operating challenges also exist, which require the use of multi-disciplinary modelling and simulation to investigate. This paper presents a high fidelity integrated IFEP simulation tool, which contains models from the electrical, mechanical and thermal physical domain. This model enables investigation from a systems level point of view. Some of the key challenges identified in the development of this model are discussed, focusing on aspects such as the existence of different time constants and the difficulties of system validation. The chosen solutions to the challenges listed above are presented and discussed. The effectiveness of the integrated IFEP simulation tool is demonstrated through a case study on the loss of propulsion load. ©2008 IEEE.