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In this work, we relied on a particular exact method to solve NP-Hard problem of determining a horizontal fragmentation scheme in relational data warehouses. The method used is that of linear programming which is distinguished by other methods by the existence of practical methods that facilitate the resolution of problems that may be described in linear form. We quote the Simplex method and the interior points. To meet the linearity of the objective function and constraints, we used initially “De Morgan” theorem, which is based on properties of sets to transform and optimize decision queries, from any form to a linear one. In addition to designing and solving the selection problem of horizontal fragmentation technique, we considered the problem in two simultaneous objectives, namely: the number of Inputs/Outputs needed to run the global workload, and number of fragments generated to identify the best solutions compared to the concept of Pareto dominance. In addition, to carry out our work, we used the Benchmark APB1 invoked by a workload, to achieve satisfactory results. [ABSTRACT FROM AUTHOR]

Several studies have invested in machine learning classifiers to protect plants from diseases by processing leaf images. Most of the proposed classifiers are trained and evaluated with small datasets, focusing on the extraction of hand-crafted features from image to classify the leaves. In this study, we have used a large dataset compared to the state-of-the art. Here, the dataset contains 14,828 images of tomato leaves infected with nine diseases. To train our classifier, we have introduced the Convolutional Neural Network (CNN) as a learning algorithm. One of the biggest advantages of CNN is the automatic extraction of features by processing directly the raw images. To analyze the proposed deep model, we have used visualization methods to understand symptoms and to localize disease regions in leaf. The obtained results are encouraging, reaching 99.18% of accuracy, which ourperforms dramatically shallow models, and they can be used as a practical tool for farmers to protect tomato against disease. [ABSTRACT FROM AUTHOR]

The upper member of the Jafnayn Formation in Wadi Rusayl and Al Khoud, Seeb Area in north Oman containsNemkovella stockariLess & Özcan, 2007, an Early Eocene orthophragminid recorded here for the first time from the Arabian Peninsula.N. stockari, the only orthophragminid identified in Jafnayn Formation, is quite distinct from any other species from Tethys in having spiral and orbitoidiform chambers around the isolepidine embryon developed before the onset of annular chambers. The Oman specimens exhibit equal-sized principal auxiliary chambers and symmetrical spirals and are assigned toN. stockari bejaensisÖzcan, Boukhalfa & Scheibner, 2014, an advanced form of theN. stockarilineage. The associated alveolinids, revised in this study, rotaliids and other age-diagnostic foraminiferal taxa in the transgressive basal part of the upper member have enabled us to revise the age as middle Ilerdian (Early Eocene), assignable to SBZ 7/8 and 8; OZ 3/4. Integrating a new record of this species from Arabian Plate margin in Belen, S Turkey, and previous records from north Africa,N. stockariappears to be a diagnostic marker for the Early Eocene along the southern peri-Tethys platforms, facilitating the Tethyan correlation by orthophragminids. The palaeobiogeographic distribution ofN. stockariis discussed. [ABSTRACT FROM PUBLISHER]

A new paraclupeid fish, Tunisiaclupea speratus, gen. et sp. nov., is described from the Upper Barremian (Early Cretaceous) of the Chotts Basin, southern Tunisia. With a series of predorsal scutes of different size and shape, it is distinguished from other paraclupeids by the following combination of characters: anterior neural spines unfused; first uroneural bearing a dorsal laminar expansion and extending anteriorly nearly to third preural centrum; and hypural diastema present. The results of a phylogenetic analysis reconfirmed the monophyly of Ellimmichthyiformes and resolved Sorbinichthyoidei (Gasteroclupeidae + Sorbinichthyidae) as the most basal clade, with the Diplomystus clade the next, Armigatidae more derived than Diplomystus clade but with few diagnostic features, and Paraclupeidae with well-supported monophyly. Tunisiaclupea was resolved as a basal paraclupeid and an intermediate lineage between Ellimma branneri from the Lower Cretaceous of Brazil and Tycheroichthys dunveganensis from the Upper Cretaceous of North America. Tunisiaclupea is among the oldest ellimmichthyiforms known so far and extends the distribution of Paraclupeidae to the southern Mediterranean Tethys in the Early Cretaceous. Ellimmichthyiform diversity reached its peak in the Mediterranean region during the early Late Cretaceous, which might have resulted from allopatric speciation promoted by the sea-level highstand and the consequential land-sea distribution with increased food input, dispersal routes, and habitat fragmentation for these fishes. [ABSTRACT FROM AUTHOR]