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In this paper, we present a method based on coupling between shock filter and diffusion process for image restoration. This method smoothes homogeneous part of the image, while it enhances edges efficiently. This selective smoothing propriety is used as a pretreatment step for an efficient classification of infrared satellite images, in order to cluster the solar field.

L’augmentation du coût des énergies classiques d’une part, et la limitation de leurs ressources d’autre part font que l’énergie photovoltaïque ‘PV’ devient de plus en plus, une solution parmi les options énergétiques prometteuses avec des avantages comme l’abondance, l’absence de toute pollution et la disponibilité en plus ou moins grandes quantités en tout point du globe terrestre. L’utilisation directe de l’énergie sortant d’un générateur PV (GPV) est possible. Par exemple, un GPV peut être directement connecté à une charge de type continu. Il faut cependant que la charge accepte la tension et le courant continus délivrés par le générateur. Cependant, dans ce cas de connexion directe, le GPV n’est exploité au mieux qu’au point de fonctionnement pour lequel la tension nominale de la charge est égale ou avoisine la tension optimale du générateur. Ceci dépend des charges, étant donnée une configuration donnée du GPV, comme on le verra dans cet article.

Thin-film solar cell technology based on hydrogenated amorphous silicon has matured over the last two decades and is capable to deliver commercial modules with almost 10 % stabilized efficiency. Moreover attention on hydrogen fuel cells is increasing as the range of potential commercial applications expands, with more than 3800 fuel cell systems being installed and operated worldwide. These systems attain high theoretical efficiencies in the range of 43.7-70.4 %, with an additional 20% as heat recovery, and operating at carbon-free conditions between 50 °C and 900 °C. In this paper the status of thin-film silicon solar cell technology is reviewed by comparing it to other major solar cell technologies. A discussion is also made upon the benefits obtained from the few potential applications, as long-term potential actions for sustainable development, and the future of Solid Oxide Fuel Cells (SOFCs). Applications of thin-film silicon modules and SOFCs are presented. EPIA (European Photovoltaic Industry Association) estimates that half of the growth in the next two years will come from thin-film technology.

La qualité des générateurs photovoltaïques (GPV) installés jusqu’à présent pouvait être contrôlée uniquement par le biais de système de mesures onéreux et peu pratique. Deux points importants sont étudiés dans le cadre de ce travail. Dans la première partie, on s’intéresse au développement d’un dispositif automatique de caractérisation de module PV à base du PIC16F877 sous condition de fonctionnement réel. Nous présentons dans la deuxième partie, une évaluation pratique des performances électriques d’un module solaire en silicium amorphe a-Si:H hybride (couches minces inorganique/substrat organique) en temps réel, orienté vers le sud avec une inclinaison de 38°, meilleure orientation pour la ville d’Oran (Algérie).

Security is a sensitive area that concerns all authorities around the world due to the emerging terrorism phenomenon. Contactless biometric technologies such as face recognition have grown in interest for their capacity to identify probe subjects without any human interaction. Since traditional face recognition systems use visible spectrum sensors, their performances decrease rapidly when some visible imaging phenomena occur, mainly illumination changes. Unlike the visible spectrum, Infrared spectra are invariant to light changes, which makes them an alternative solution for face recognition. However, in infrared, the textural information is lost. We aim, in this paper, to benefit from visible and thermal spectra by proposing a new heterogeneous face recognition approach. This approach includes four scientific contributions. The first one is the annotation of a thermal face database, which has been shared via Github with all the scientific community. The second is the proposition of a multi-sensors face detector model based on the last YOLO v3 architecture, able to detect simultaneously faces captured in visible and thermal images. The third contribution takes up the challenge of modality gap reduction between visible and thermal spectra, by applying a new structure of CycleGAN, called TV-CycleGAN, which aims to synthesize visible-like face images from thermal face images. This new thermal-visible synthesis method includes all extreme poses and facial expressions in color space. To show the efficacy and the robustness of the proposed TV-CycleGAN, experiments have been applied on three challenging benchmark databases, including different real-world scenarios: TUFTS and its aligned version, NVIE and PUJ. The qualitative evaluation shows that our method generates more realistic faces. The quantitative one demonstrates that the proposed TV -CycleGAN gives the best improvement on face recognition rates. Therefore, instead of applying a direct matching from thermal to visible images which allows a recognition rate of 47,06% for TUFTS Database, a proposed TV-CycleGAN ensures accuracy of 57,56% for the same database. It contributes to a rate enhancement of 29,16%, and 15,71% for NVIE and PUJ databases, respectively. It reaches an accuracy enhancement of 18,5% for the aligned TUFTS database. It also outperforms some recent state of the art methods in terms of F1-Score, AUC/EER and other evaluation metrics. Furthermore, it should be mentioned that the obtained visible synthesized face images using TV-CycleGAN method are very promising for thermal facial landmark detection as a fourth contribution of this paper.

Saffron "Crocus sativus" is a plant of the Iridaceae family. Its therapeutic virtues have been known since antiquity; it is used in traditional medicine and culinary preparations. It is also known for its use in cosmetics because of its beneficial pharmacological activities for human skin. In particular, saffron tepals are the main by-product of saffron processing; they contain several bioactive compounds such as mineral agents, anthocyanins, monoterpenoids, carotenoids, flavonoids, and flavonols (kaempferol). This review aims to describe the different properties of saffron flower tepals, including their botanical characteristics, phytochemical composition, biological activities, and cosmetology and perfumery uses. [ABSTRACT FROM AUTHOR]

This paper summarises the findings of many studies and surveys in the water and energy sectors in order to make recommendations for water and energy policies in Algeria. We provide an overview of current policy concerning water, energy, and climate change. We investigate the impact of the water-energy nexus on current policy developments. We made specific proposals to aid in the integration of water and energy policies in Algeria. This study demonstrates how, in the absence of integrated policies, the inextricable historical linkages between water and electricity have given rise to spurious trade-offs between water and energy. Drought and climate change are projected to increase demand for electricity, and water sector adaptation strategies have the potential to contribute to climate change by encouraging investment in energy-intensive technologies such as desalination and enhanced wastewater treatment. The findings indicate that demand management programmes and water pricing regulations that lower water and energy intensity in important industries are likely to benefit Algeria's whole economy and environment. The findings are equally applicable to other countries confronted with the burden of developing appropriate strategies to manage their water and energy issues.