Rhammatocerus schistocercoides locust outbreaks in Mato Grosso (Brazil): A long-standing phenomenon
Evidence obtained orally or from publications clearly indicate that Rhammutocerus schistocercoides Rehn, 1906 (Orthoptera: Acrididae Gomphocerinae) outbreaks in Mato Grosso (Brazil) are a long-standing phenomenon, both in terms of their extent and nature. Current theories on the origins of these outbreaks therefore must be drastically revised, especially those that blame the accelerated agricultural development that has occurred in these regions since 1980.
Static and dynamic cartographies of the biotopes of the grasshopper Rhammatocerus schistocercoides (Rehn, 1906) in the state of Mato Grosso, Brazil
Les pullulations de #Rhammatocerus schistocercoides# ont lieu dans des biotopes specifiques. A partir d'une etude detaillee des donnees de terrain, des cartes des biotopes aptes a la reproduction, au developpement et a la survie de l'insecte ont ete realisees. Une cartographie statique a ete developpee sur la base d'une interpretation analogique des images Landsat TM. Les images NOAA ont egalement ete utilisees pour elaborer une cartographie dynamique permettant le suivi de l'evolution phenologique de la vegetation
Evaluation of buckling load and dynamic performance of steel shear wall retrofitted with strips made of shape memory alloy
One of the most imperfections of the steel shear wall is out of plane displacements that cause severe damage in both structural and non-structural elements. In this paper, the effects of shape-memory alloys on steel shear walls are investigated. First, a numerical analysis using the finite element method in ABAQUS software has been carried out according to an experimental test. The results of the numerical analysis have been verified with experimental results. Next, shape-memory alloy fibers have been added vertically and horizontally to various parts of the steel shear wall. The results show that retrofitting with the shape-memory alloy reduces the out-of-plane displacement of the steel shear wall under both cyclic and seismic loadings. Besides, the buckling load in the steel shear wall increases when it is retrofitted with the shape-memory alloy. Also, the total out-of-plane movement (accumulated absolute displacements) of the steel shear wall and non-structural damage are controlled by the characteristic of a shape-memory alloy material called “super-elastic”.