The Algero-Tunisian confines (Tebessa region) is partially composed of Cenomano- Turonian carbonate outcrops; therefore, it presents a good example to highlight the black shale levels reported over a short period, around the Cenomanian-Turonian boundary. The lithostratigraphic study made it possible to specify the paleoenvironment during the Cenomano-Turonian in the Tebessa region. At that time, the depositional environment emphasized a relatively deep, calm and often confined ocean environment that was significantly shalloweron the north part of the study area. The lithology and the distribution of the facies in the Constantine domain allow us to underline the pelagic influences during the Upper Cretaceous and neritic during the lower Cretaceous period. We note a maximum thickness of the Cenomano- Turonian in the southern zones and a minimum (100m) appears further north. This Palaeogeographic organization continue laterally in Tunisia on the extension of the Constantine mole.

In this paper, we propose a new numerical method for acoustics microwaves detection of an acoustics microwaves signal during the propagation of acoustics microwaves in a piezoelectric substrate zinc oxide (ZnO). We have used support vector machines (SVMs), the originality of this method is the accurate values that provides this technique help to identify undetectable waves that we can not identify with the classical methods. We classify all the values of the real part and the imaginary part of the coefficient attenuation with the acoustic velocity in order to build a model from which we note the types of microwaves acoustics (bulk waves or surface waves or leaky waves). We obtain accurate values for each of the coefficient attenuation and acoustic velocity. This study will be very interesting in modelling and realisation of acoustics microwaves devices (ultrasound, radiating structures, filter SAW…) based on the propagation of acoustics microwaves.

Located in northeast Algerian, the coastal aquifer of Taleza constitutes a significant source of groundwater. It contains hundreds of private wells installed by the population for several purposes including drinking water. Recently, the groundwater has become quite salinized. Furthermore, some people have noted the presence of a bad odor, as rotten eggs, in the groundwater pumped from their wells. The groundwater quality is mostly controlled by two factors: 1) natural processes related to aquifer lithology, and soil/rock interactions with groundwater, and 2) anthropogenic activities. However, the later activities can be considered as the most serious sources of groundwater contamination. This paper describes a review of potential anthropogenic sources of groundwater contamination over the Taleza territory. Several different potential anthropogenic sources were identified, such as cultivated fields, private sanitation systems, random urbanisation, over-exploitation of groundwater, solid waste dumpsites, and cemeteries. Consequently, efficient and durable groundwater protection planning is urgently required, to limit and possibly remediate groundwater contamination related to anthropogenic activities.

This paper proposes a compromise-tolerant (t,n)-threshold certification management scheme for MANETs. Our solution allows to mitigate the impact of compromised nodes that participate in the certification service. In our design, certification management is achieved anonymously by an Anonymous Certification Authority (ACA). The latter is fully distributed into multiple disjointed coalitions of nodes whose structure is made hidden. This prevents an adversary from taking the control of the ACA by arbitrarily compromising t or more nodes. In other words, our proposal enhances the compromise-tolerance to more than the threshold number t of nodes without breaking down the whole certification system. As a result, our scheme requires a very smaller threshold than traditional schemes, which improves considerably the service availability. The experimental study shows a clear advantage over traditional threshold-based certification schemes by ensuring a significant positive compromise between security and availability of certification service.

Let B(H) be the C* -algebra of all bounded linear operators acting on a complex separable Hilbert space H . We shall show that: 1. The class of all selfadjoint operators in B(H) multiplied by scalars is characterized by ∀X ∈ B(H), S2X +XS2 =>2||SXS||, (S ∈ B(H)). 2. The class of all normal operators in B(H) is characterized by each of the three following properties (where DS = S*S-SS* , for S ∈ B(H)), (i) ∀X ∈ B(H), S2X + XS2 =>2||SXS||,(S ∈ B(H)), (ii) S*DSS = 0 = SDSS*,(S ∈ B(H)), (iii) S*DSS=> 0 =>SDSS*,(S ∈ B(H)).