Using a risk matrix for Risk mapping constitutes the basis of risk management strategy. It aims to classify the identified risks with regards to their management and control. This risk classification, which is based on the frequency and the severity dimensions, is often carried out according to a procedure founded on experts’ judgments. In order to overcome the subjectivity bias of this classification, this paper presents the contribution of the Principal Components Analysis (PCA) method: an exploratory method for graphing risks based on factors that allow a better visualized classification of scenarios accidents. Still, the commonly encountered problem in the data classified by the PCA method resides in the main factors of classification; we judged useful to frame these letters by an algebraic formulation to make an improvement of this classification possible. The obtained results show that the suggested method is a promising alternative to solve the recurring problems of risk matrices, notably in accident scenarios’ classification.

Mobile Wireless Sensor and Actor Networks (MWSANs) can simply be defined as an extension of Wireless Sensor and Actor Networks (WSANs) in which the actor nodes are mobile. As such, in addition to challenges existing in WSAN, the mobility also imposes new challenges such as localization of actors, cooperative tracking of both actor-actor and actor-sensor collaboration, and communication infrastructure between distant actors. New communication protocols, specific to MWSANs, are needed. In this paper, we propose a self-organization and data collection protocol in order to provide energy efficiency, low latency, high success rate and suitably interactions between sensors and actors and take benefit from the mobility and resources existing on the network’s actor nodes. The actor nodes move according to RWP mobility model. Each actor, during its pause time creates a temporary cluster, and is the head of it, collects and processes sensor data and performs actions on the environment based on the information gathered from sensor nodes in its cluster. Once an actor detects a base station it delivers the collected data to it. The simulations carried out (with TOSSIM tool), comfort us with good performances results.

Scene text presents challenging characteristics mainly related to acquisition circumstances and environmental changes resulting in low quality videos. In this paper, we present a scene text detection algorithm based on pseudo Zernike moments (PZMs) and stroke features from low resolution lecture videos. Algorithm mainly consists of three steps: slide detection, text detection and segmentation and non-text filtering. In lecture videos, slide region is a key object carrying almost all important information; hence slide region has to be extracted and segmented from other scene objects considered as background for later processing. Slide region detection and segmentation is done by applying pseudo Zernike moment’s based on RGB frames. Text detection and extraction is performed using PZMs segmentation over V channel of HSV colour space, and then stroke feature is used to filter out non-text region and to remove false positives. The algorithm is robust to illumination, low resolution and uneven luminance from compressed videos. Effectiveness of PZM description leads to very few false positives comparing to other approached. Moreover resulting images can be used directly by OCR engines and no more processing is needed.

The groundwater quality of Tadjenanet- Chelghoum Laid Semi-arid region was assessed for irrigation suitability; where the intensity of salinization process depends on soil characteristics, water quality, irrigation practices and in particular the inefficiency of the drainage system. The drought of the last decade has created an agricultural deficit due to high evapotranspiration, influencing the water salinity. To achieve this assessment, thirty groundwater samples were collected at identical locations from deeper wells. The physicochemical parameters such as, pH, electrical conductivity (EC), total hardness (TH), Ca²^+$, Mg²^+$, Na^+$, K^+$, HCO3^-$, SO4²^-$, Cl^-$ and NO3^-$ have been studied. Obtained results were measured and interpreted with different irrigation indexes like EC, sodium percentage (SP), sodium adsorption ratio (SAR), residual sodium carbonate (RSC), permeability index (PI) and Kelly’s ratio (KR). These parameters combined allowed to conclude that the quality of groundwater was roughly suitable for irrigation.

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.