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61.
The geotechnical features of the three members of the Neogene of the Grenade basin (South Spain) are described from 170 samples. The upper member shows 30 meters of soil with 46–90% silt, 5–52% clays (34 to 82% smectitic), high durability-high plasticity and high swelling potential. In the upper 10 meters, some very local layers of silts and gypsum are observed and at the bottom 20 meters of detritic deposits. The middle member is composed by 80 to 250 meters of marly soils with 40–92% of silt fraction, 5 to 60% of clay fraction (40 to 100% illitic), high weathering index and low swelling potential. Some turbiditic and evaporitic deposits, several tens of meters thick, are also locally interlayered. The upper member is composed by 100 meters of detritic-carbonated soils with 0–88% of sand fraction and 5–57% of clay fraction (30–80% smectitic). The weathering index and the swelling potential are similar to the middle member, even with its higher smectitic contain and because of the swelling inhibition derived from the higher carbonate and sulfate proportions. 相似文献
62.
63.
Fathi Habashi Farouk T. Awadalla Xin-Bao Yao 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1987,38(2):115-126
When phosphate rock is leached with hydrochloric acid, radium can be removed by co-precipitation with Ba0.4Ca0.6SO4 and uranium by extraction with a 5% solution of tributyl phosphate in hexane or Varsol. Phosphoric acid is then separated from calcium chloride solution and other impurities by extraction with undiluted tributyl phosphate. The lanthanides can be precipitated from the raffinate by NH3, and CaSO4.2H2O by H2SO4 to regenerate HCl for recycle. The organic phase containing H3PO4 can be stripped by NH3 to yield ammonium phosphate and to regenerate the tributyl phosphate for recycle. Fluorine can be precipitated from the initial leach solution as Na2SiF6. 相似文献
64.
Rabehi A. Amrani M. Benamara Z. Akkal B. Ziane A. Guermoui M. Hatem-Kacha A. Monier G. Gruzza B. Bideux L. Robert-Goumet C. 《Semiconductors》2018,52(16):1998-2006
Semiconductors - In this paper, we studied the electrical characteristic of Schottky diodes based on gold contact on nitridated GaAs substrates. The used (100) GaAs substrate is n-type with... 相似文献
65.
J. Batle C. H. Raymond Ooi M. Abutalib Ahmed Farouk S. Abdalla 《Quantum Information Processing》2016,15(7):2839-2850
Quantum correlations are almost impossible to address in bulk systems. Quantum measures extended only to a few number of parties can be discussed in practice. In the present work, we study nonlocality for a cluster of spins belonging to a mineral whose structure is that of a quantum magnet. We reproduce at a much smaller scale the experimental outcomes, and then, we study the role of quantum correlations there. A macroscopic entanglement witness has been introduced in order to reveal nonlocal quantum correlations between individual constituents of the azurite mineral at nonzero temperatures. The critical point beyond which entanglement is zero is found at \(T_c < 1\,\mathrm{K}\). 相似文献
66.
J. Batle C. H. Raymond Ooi Ahmed Farouk M. Abutalib S. Abdalla 《Quantum Information Processing》2016,15(8):3081-3099
Quantum correlations are thought to be the reason why certain quantum algorithms overcome their classical counterparts. Since the nature of this resource is still not fully understood, we shall investigate how multipartite entanglement and non-locality among qubits vary as the quantum computation runs. We shall encounter that quantum measures on the whole system cannot account for their corresponding speedup. 相似文献
67.
Ali Khebizi Hassina Seridi-Bouchelaghem Bouallem Benatallah Farouk Toumani 《Service Oriented Computing and Applications》2017,11(2):163-181
We investigate the problem of web service instances migration in the context of business protocol evolution, i.e., how to convert active instances of web services from an old version of a business protocol into a new one? We propose a framework based on a declarative approach to support service providers in defining fine-grained migration strategies of active instances. While the existing approaches for instances migration force the migrated instances to reflect the original ones as accurately as possible, in our approach we give to service providers the ability to declaratively define the constraints that drive the instances migration process. A migration strategy is expressed as a set of instances migration rules which are specified using an instance mapping language made of a set of generic migration patterns. The proposed approach has been implemented in a software tool that provides useful functionalities for protocol managers. 相似文献
68.
Co-Training by Committee: A Generalized Framework for Semi-Supervised Learning with Committees 下载免费PDF全文
Mohamed Farouk Abdel Hady Friedhelm Schwenker 《International Journal of Software and Informatics》2008,2(2):95-124
Many data mining applications have a large amount of data but labeling data is often di cult, expensive, or time consuming, as it requires human experts for annotation.Semi-supervised learning addresses this problem by using unlabeled data together with labeled data to improve the performance. Co-Training is a popular semi-supervised learning algorithm that has the assumptions that each example is represented by two or more redundantly su cient sets of features (views) and additionally these views are independent given the class. However, these assumptions are not satis ed in many real-world application domains. In this paper, a framework called Co-Training by Committee (CoBC) is proposed, in which an ensemble of diverse classi ers is used for semi-supervised learning that requires neither redundant and independent views nor di erent base learning algorithms. The framework
is a general single-view semi-supervised learner that can be applied on any ensemble learner to build diverse committees. Experimental results of CoBC using Bagging, AdaBoost and the Random Subspace Method (RSM) as ensemble learners demonstrate that error diversity among classi ers leads to an e ective Co-Training style algorithm that maintains the diversity of the underlying ensemble. 相似文献
69.
Acoustically generated flows in microchannel flexural plate wave sensors: Effects of compressibility
Ersin SayarBakhtier Farouk 《Sensors and actuators. A, Physical》2011,171(2):317-323
Acoustically generated flowfields in flexural plate wave sensors filled with a Newtonian liquid (water) are considered. A computational model based on compressible flow is developed for the sensor with a moving wall for pumping and mixing applications in microchannels. For the compressible flow formulation, an isothermal equation of state for water is employed. The velocity and pressure profiles for different parameters including flexural wall frequency, channel height, amplitude of the wave and wave length are investigated for four microchannel height/length geometries. It is found that the flowfield becomes pseudo-steady after sufficient number of flexural cycles. Both instantaneous and time averaged results show that an evanescent wave is generated in the microchannel. The predicted flows generated by the FPWs are compared with results available in the literature. The proposed device can be exploited to integrate micropumps with complex microfluidic chips improving the portability of micro-total-analysis systems. 相似文献
70.
This paper investigates the problems of stability and synchronization for high-order recurrent neural networks with mixed delays. Firstly, we establish sufficient conditions to ensure the asymptotic stability and then the exponential synchronization. Furthermore, our results are applied to two chosen systems to demonstrate the effectiveness of the obtained theoretical results. 相似文献