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Determining association rules of significant interest is an essential task within data mining and statistical analysis. In this paper, we first precisely define the notion of association rule. For this, we introduce a general model, which includes the usual transaction model, and which allows many operations on the association rules. Then, we interpret association rules as statistical decision rules. This interpretation leads to four decisional measures, one of them being the usual confidence. Then, we give some strategies based on the use of these four decisional measures in order to select or to construct association rules with a given consequent. We finally present an experimental study to illustrate these strategies. This study is carried out in R language, with the R‐package we specifically built for association rules mining. [ABSTRACT FROM AUTHOR]

Reports on rare earth elements fractionation between scheelite and apatite in hydrothermal conditions. Geochemical analysis of hydrothermal apatite and scheelite; Indication of crystallization; Identification of successive ore-bearing fluids.

The mining of frequent itemsets and association rules is a core problem in data mining and an essential task in data analysis. In this paper, we present SufRec, a new algorithm for finding frequent itemsets and association rules. We give two versions. In both versions, the mining of the frequent itemsets is decomposed as a sequence of tasks. The first version (the SufRecDep algorithm) proceeds the tasks successively, each one using the results of the previous ones. The second version (the SufRecInd algorithm) performs the tasks independently of each other. Both versions are recursive with respect to the items and have thus the advantage to be particularly efficient for updating the mining process when new items are added to the database or when others are excluded. Moreover, the task-independent processing of SufRecInd makes it very easy to build parallel versions of SufRec. We present two parallel SufRec algorithms. With the first one, P-FIFO-SufRec, the processors perform the tasks according to the order in which the items appear in the database, preserving the recursive nature of SufRec. For second one, P-PAST-SufRec, the set of items is fixed and the tasks are pre-assigned to each processor. In order to evaluate the performance of SufRec, we carry out a consequent experimental study. In particular, we compare its running times with those of well-known parallel and non-parallel frequent itemsets mining algorithms. • Construction of SufRec, a new algorithm for frequent itemsets mining (FIM). • Construction of parallel versions of SufRec algorithm. • Experimental study comparing SufRec with well-known FIM algorithms. • Applications to the case where the list of items changes over time. [ABSTRACT FROM AUTHOR]

Highlights: [•] The role of the transient phase from aerated to anoxic on iron corrosion is studied. [•] Ferrous carbonates are formed at the metallic interface in a ferric corrosion layer. [•] The corrosion rate corresponds to a general corrosion mechanism in an anoxic medium. [ABSTRACT FROM AUTHOR]

Abstract: Doppler broadening of annihilation gamma-line combined with a slow positron beam (SPB) was used to measure the momentum density distribution of annihilating pairs in a set of sintered UO2 samples implantated with 800-keV 136Xe2+ at fluences of 1×1015 and 1×1016 Xecm−2. The effect of prolonged post-implantation annealing at 1673 and 1873K, grain size, and 152-MeV Iodine irradiation were studied by analysis of S(E) profiles and S-W maps and discussed versus secondary ion mass spectroscopy (SIMS), scanning transmission electron microscopy results. Spectroscopy with SPB and SIMS is an excellent combination of complementary techniques for studying the formation and evolution of Xe-bubbles, and Xe retention. [Copyright &y& Elsevier]

Abstract: This study explores the dynamics of porosity and reactive surface area changes during porous limestone dissolution by CO2-rich water. The Sr and Ca concentrations in both the rock and the outlet solution are used to evaluate the reactive surface area changes of the two rock-forming calcites, i.e. micrite grains and sparite crystals, which have different trace element signatures. The geometric surface area measured with X-ray microtomography decreases slightly whereas the reactive surface area increases continuously with increasing porosity from 20.3 to 30.2%. Surprisingly, changes in reactive surface areas are very different between the two calcites. The reactive surface area changes in the micrite are parabolic while the reactive surface area of sparite increases greatly. The numerical model HYTEC is used to model the change in reactive surface areas during the experiment. Different geometrical models are tested. The model based on spherical-grain dissolution and spherical-pore growth fails to reproduce the experimental results, while the sugar-lump model provides reasonable agreement with the experiment. [Copyright &y& Elsevier]

Abstract: This study explores the dynamics of porosity and reactive surface area changes during porous limestone dissolution by CO2-rich water. The Sr and Ca concentrations in both the rock and the outlet solution are used to evaluate the reactive surface area changes of the two rock-forming calcites, i.e. micrite grains and sparite crystals, which have different trace element signatures. The geometric surface area measured with X-ray microtomography decreases slightly whereas the reactive surface area increases continuously with increasing porosity from 20.3 to 30.2%. Surprisingly, changes in reactive surface areas are very different between the two calcites. The reactive surface area changes in the micrite are parabolic while the reactive surface area of sparite increases greatly. The numerical model HYTEC is used to model the change in reactive surface areas during the experiment. Different geometrical models are tested. The model based on spherical-grain dissolution and spherical-pore growth fails to reproduce the experimental results, while the sugar-lump model provides reasonable agreement with the experiment. [Copyright &y& Elsevier]