Effect of earth discontinued to the electrical field distribution in rod-plane air gaps under lightning impulse

This paper, will present some results of investigations carried out on electric field distribution on the surface of a discontinuous plane of short rod-plane air gap arrangement. For this purpose, we have used different results obtained by an experimental model and a numerical method for computation used the finite elements methods (FEM). The effect of interface on the field stress has also been studied, As a result, the interface locally reinforces the electric field, and then the electric field increases at the interface may lead to a discharge between the high voltage rode and the interface. In the vicinity of the interface, we have observed a kind of discontinuity in the evolution of the electric field intensity. This latter becomes greater than the value obtained in the case of gaps with homogeneous plane earth. The electric field distribution, obtained by means of the computational procedure, is in good agreement with the experimental results.Keywords: discontinuous plane; the electric field; homogeneous plane; the finite elements methods (FEM

Effect of plastic fins on a traditional solar still's efficiency

Solar distillation is a relatively straightforward and environmental method. It is used in many countries and especially in isolated areas to treat polluted water. In this context, two similar solar stills of 50 x 50 cm were used in the same climatic conditions in order to test the influence of plastic fins on the performance of this device. The results show that there is a negative effect on the output of the distiller with a rate of 8.8 %. So this way is not recommended for researchers in this field

Effect of plastic fins on a traditional solar still's efficiency

Solar distillation is a relatively straightforward and environmental method. It is used in many countries and especially in isolated areas to treat polluted water. In this context, two similar solar stills of 50 x 50 cm were used in the same climatic conditions in order to test the influence of plastic fins on the performance of this device. The results show that there is a negative effect on the output of the distiller with a rate of 8.8 %. So this way is not recommended for researchers in this field

Design and Realization of a Refuse Sorting System for Educational Perspective

Our project focused on developing a waste sorting machine for metal, plastic, and glass for educational purposes. We divided it into several parts, including waste types, sorting methods, and recycling processes. All processes were done highlighting the use of the Arduino Uno controller. Additionally, we outlined the tools required for an automated sorting system and go beyond simulations by creating a prototype. Our goal is to establish a waste sorting machine that promotes recycling and environmental protection, providing both financial returns and sustainability by diverting waste from burial or incineration, thus mitigating pollution

Seasonal variation of the diet of the Fennec fox, Vulpes zerda (Canidae, Carnivora), in Algeria

Les variations saisonnières du régime alimentaire du Fennec, Vulpes zerda, ont été étudiées à partir de crottes collectées à Ben Ahmed, région de Ghardaïa (Sahara septentrional algérien). De l’automne 2010 au printemps 2011, 130 crottes ont livré 726 proies animales appartenant à 17 ordres, 30 familles et 75 espèces. Les proies principales ont été les Insectes (554 individus), suivis par les Mammifères (142 individus) et les Arachnides (14 individus). Cependant, en biomasse les Mammifères ont été les proies dominantes (86,5 %) devant les Insectes (10,7 %) et les oiseaux (1,2 %). Un spectre semblable a été trouvé au cours des trois saisons étudiées, toutefois les fréquences des principaux groupes ont varié significativement. L’automne a été la saison de plus forte prédation sur les Mammifères, en hiver les Isoptères ont été les proies les plus nombreuses, au printemps ce furent les Orthoptères et les Arachnides. La prédation des Coléoptères, Squamates et Oiseaux a été stable au fil des saisons. Ces résultats confirment que le Fennec est un prédateur opportuniste.The seasonal diet of the Fennec fox, Vulpes zerda, has been investigated in Ben Ahmed, Ghardaïa region (northern Sahara, Algeria) using scat content analysis. In 130 scats collected from autumn 2010 to spring 2011 we identified 726 animal prey items belonging to 17 orders, 30 families and 75 species. The main preys were insects (554 individuals), followed by mammals (142 individuals) and arachnids (14 individuals). However, biomass was dominated by mammals, (86.5 %), followed by insects (10.7 %) and birds (1.2 %). Similar patterns were observed among the seasons, but the frequencies of the main contributing taxa were significantly different. Autumn was the season when mammals were the most consumed; in winter Isoptera were the most numerous preys; in spring Orthoptera and Arachnida were abundantly fed upon, whereas predation of Coleoptera, squamates and birds were similar along the seasons. These results confirm that the fennec fox is an opportunistic predator

ELECTRIC FIELD MEASUREMENT IN ROD-DISCONTINUED PLANE AIR GAPS USING DISTRIBUTED CAPACITY PROBE

<p>The present experimental carried out investigations<em> </em>aimed at elucidating the effect of earth discontinuity on the breakdown voltage of short rod-plane air gap (80 to160 mm) under negative lightning impulses (-1.2/50ms).We also carried out investigations on electric field measurement on the surface of a discontinuous plane of a rod-plane air gap arrangement. For this purpose, we used a probe with distributed capacity, under negative lightning applied impulse voltage. The probe is incorporated on the same level of plane surface.The interface locally reinforces the electric field. The electric field increases at the interface may lead to a discharge between the high voltage rode and the interface. In the vicinity of the interface, we observe a kind of discontinuity in the evolution of the electric field intensity. This one becomes greater than the value obtained in the case of gaps with homogeneous plane earth.</p