USING GIS AND PHOTOGRAMMETRY FOR ASSESSING SOLAR PHOTOVOLTAIC POTENTIAL ON FLAT ROOFS IN URBAN AREA CASE OF THE CITY OF BEN GUERIR / MOROCCO

Renewable energy sources are at the forefront of political discussions around the world because of the scarcity of fossil fuels and climate change caused by the accumulation of greenhouse gases. By 2030, Morocco will cover 52% of these energy needs through renewable energies, in order to preserve the environment (COP 22). This paper aims to estimate the potential of photovoltaic solar energy from flat roofs in the city of Ben Guerir, Morocco using remote sensing and GIS data. To achieve this goal, vector orthophoto resulting from the photogrammetric restitution acquired in 2015 were used to generate a 3D model (DSM). The annual solar irradiation is calculated by the analyser of the solar tool. Each roof is calculated based on algorithms for the most common solar panel technologies (mono-si and poly-si). The applicability of this methodology has been demonstrated in the urban area of Benguerir, Morocco, and can be widespread in any other region of the world. The results obtained for a total roofing surface of 135 Ha, i.e. more than 345 Gwh of electricity annually generate. For an average roof of 60 m2 that could supply 5 to 6 households; A planned investment between 118,218 and 167,296 DH, and an annual maintenance charge of 2%. This study may be an initial assessment of solar potential in the city, which can be used to support the management decision regarding investment in the urban solar system

Undulation instabilities in the meniscus of smectic membranes

Using optical microscopy, phase shifting interferometry and atomic force microscopy, we demonstrate the existence of undulated structures in the meniscus of ferroelectric smectic-C* films. The meniscus is characterized by a periodic undulation of the smectic-air interface, which manifests itself in a striped pattern. The instability disappears in the untilted smectic-A phase. The modulation amplitude and wavelength both depend on meniscus thickness. We study the temperature evolution of the structure and propose a simple model that accounts for the observed undulations.Comment: Submitted to PR

Marine health of the Arabian Gulf: Drivers of pollution and assessment approaches focusing on desalination activities

The Arabian Gulf is one of the most adversely affected marine environments worldwide, which results from combined pollution drivers including climate change, oil and gas activities, and coastal anthropogenic disturbances. Desalination activities are one of the major marine pollution drivers regionally and internationally. Arabian Gulf countries represent a hotspot of desalination activities as they are responsible for nearly 50% of the global desalination capacity. Building desalination plants, up-taking seawater, and discharging untreated brine back into the sea adversely affects the biodiversity of the marine ecosystems. The present review attempted to reveal the potential negative effects of desalination plants on the Gulf's marine environments. We emphasised different conventional and innovative assessment tools used to assess the health of marine environments and evaluate the damage exerted by desalination activity in the Gulf. Finally, we suggested effective management approaches to tackle the issue including the significance of national regulations and regional cooperation