Search

Published After
Published Before

Search Results

  • Assessment of the vulnerability of zemmouri bay to coastal erosion, diachronic study between 1957 and 2017
    15-30
    Views:
    189

    The analysis and understanding of coastline variability and coastal erosion trends, and accretion are essential to scientists and local decision-makers to guide shoreline management regulations and decisions. This study focuses on detecting and analyzing historical changes in the Zemmouri (Central Algeria) shoreline position between 1957 and 2017. We collected all the necessary data related to the Zemmouri bay to achieve our objective, such as satellite images, aerial photos, and topographical surveys carried out by the DGPS, all between 1957 and 2017 DSAS calculation tool. Diachronic analysis of aerial photographs and satellite images of Zemmouri Bay revealed that only 39% of sandy beaches are eroding while 3% have some stability. The maximum erosion at Mazer East beach is -1.25m/year. The maximum accretion rate of +1.40m/year at Blue Waves beach, mainly due to the implantation of breakwaters at this beach which created tombolos favoring sand accumulation and beach widening.

  • In-flight icing characteristics of unmanned aerial vechicles during special atmospheric condition over the Carpathian-basin
    74-80
    Views:
    59

    The in-flight aerial icing phenomena is very important for the Unmanned Aerial Vehicles (UAV) because it causes some serious problems such as reduced lift and increased drag forces, significantly decreased angle of attack, increased weight, structural imbalances and improper radio communications. In order to increase flight safety of UAV’s we develop an integrated meteorological support system for the UAV pilots, mission controllers and decision makers, too. In our paper we show the in-flight structural icing estimation method as a part of this support system based on a simple 2D ice accretion model predictions. We point out the role of the ambient air temperature, cloud liquid water content, airfoil geometry and mainly the true airspeed in the icing process on the wings of UAVs. With the help of our model we made an estimation of geometry and amount of ice accretion on the wing of a short-range and a high-altitude and long-endurance UAVs during a hypothetical flight under a typical icy weather situation with St clouds over the Carpathian-basin (a cold-pool situation case study). Finally we point out that our icing estimation system can easily be adapted for supporting the missions of UAVs.