Desertification Detection in Makkah Region based on Aerial Images Classification

Desertification has become a global threat and caused a crisis, especially in Middle Eastern countries, such as Saudi Arabia. Makkah is one of the most important cities in Saudi Arabia that needs to be protected from desertification. The vegetation area in Makkah has been damaged because of desertification through wind, floods, overgrazing, and global climate change. The damage caused by desertification can be recovered provided urgent action is taken to prevent further degradation of the vegetation area. In this paper, we propose an automatic desertification detection system based on Deep Learning techniques. Aerial images are classified using Convolutional Neural Networks (CNN) to detect land state variation in real-time. CNNs have been widely used for computer vision applications, such as image classification, image segmentation, and quality enhancement. The proposed CNN model was trained and evaluated on the Arial Image Dataset (AID). Compared to state-of-the-art methods, the proposed model has better performance while being suitable for embedded implementation. It has achieved high efficiency with 96.47% accuracy. In light of the current research, we assert the appropriateness of the proposed CNN model in detecting desertification from aerial images.     

IoT scheduling for higher throughput and lower transmission power

Wireless Networks - The massive increase in the Internet of Things (IoT) has brought a diverse long-range, low-power, and low bit-rate wireless network technologies. The LoRa a low-power wide area...     

Fatty acid methyl and ethyl esters obtained from rare seeds from Tunisia: Ammi visnaga,Citrullus colocynthis,Datura stramonium,Ecballium elaterium,and Silybum marianum

This work aims to study the properties of fatty acid methyl and ethyl esters from Tunisian oils in order to assess their potential use as biofuel sources. The oils chosen for this study have been scarcely researched by other authors and are very interesting for a possible exploitation as fuels. Most of them are nonedible sources and all of them can be grown in arid places with no need of supplementary water: the bishop’s weed Ammi visnaga, the bitter apple Citrullus colocynthis, the stramonium Datura stramonium, the devil pickle Ecballium elaterium, and the milk thistle Silybum marianum.     

Combined effects of blasting and geological structure on rock mass stability—a case study from the Marrakech–Agadir highway,Morocco

Bulletin of Engineering Geology and the Environment - The Marrakech–Agadir highway crosses mountainous areas of the Western High Atlas of Morocco with a high risk of slope instability. The...     

Spectral analysis of thermoelastic systems under nonclassical thermal models

We study some spectral properties of the solutions to generalized thermoelastic systems under Lord–Shulman, Green–Lindsay, and Green–Naghdi of type-II models. First, we prove that the linear operator of each model has compact resolvent and generates a C₀?semigroup in an appropriate Hilbert space. We also show that there is a sequence of generalized eigenfunctions of the linear operator that forms a Riesz basis. By a detailed spectral analysis, we obtain the expressions of the spectrum and we deduce that the spectrum-determined growth condition holds. Therefore, if the imaginary axis is not an asymptote of the spectrum, we prove that the energy of each model decays exponentially to a rate determined explicitly by the physical parameters. Finally, some simulations are given for each model to support our results.     

Prevalence of JC virus viraemia in HIV-infected patients with or without neurological disorders: a prospective study

Superoxide dismutase (SOD) and catalase (CAT) activities were measured in blood from 420 individuals: control population 126, males and females, age between 50 to 93 years of age without any relevant pathology. Pathological population: 294 patients, males and females, age between 50 to 93 years of age, with some disease in the cardiovascular system and in the osteoarticular system, myoma, prostatic pathologies, Chronic Obstructive Pulmonary Disease (EPOC), and Acute Cerebral Vascular Accident (ACVA). The method of Minami and Yoshikawa (SOD) and the method of Aebi (CAT) were judged the techniques of choice for a population study. Statistical methods: ANOVA and Student's "t". 1) The results were that levels of activity for SOD and CAT were increased for women in control population, and 2) the level of activity for CAT decreases with aging. In the pathological population, we detected: 3) increased activity for SOD in cardiovascular diseases, myomas, EPOC and ACVA. 4) for CAT the level of activity decreases in cardiovascular and prostatic diseases, EPOC and ACVA. 5) while in osteoarticular diseases levels of activity for SOD and CAT were standard, but SOD level decreases with aging, for CAT in cardiovascular diseases and EPOC, too. Both enzymes work to balance the antioxidant system.     

Variational Bayesian inference for infinite generalized inverted Dirichlet mixtures with feature selection and its application to clustering

We developed a variational Bayesian learning framework for the infinite generalized Dirichlet mixture model (i.e. a weighted mixture of Dirichlet process priors based on the generalized inverted Dirichlet distribution) that has proven its capability to model complex multidimensional data. We also integrate a “feature selection” approach to highlight the features that are most informative in order to construct an appropriate model in terms of clustering accuracy. Experiments on synthetic data as well as real data generated from visual scenes and handwritten digits datasets illustrate and validate the proposed approach.     

Coding graphene metasurface modeling using MoM‐GEC method for dynamic diffusion and scattering control at Terahertz range

In this article, we present an electromagnetic study of electrically programmable graphene‐based metasurface with individual scattering control. Our investigation is based on the method of moments combined with the generalized equivalent circuit (MoM‐GEC) approach. We show that, tuning the unit cell's conductivity leads to change its input impedance and scattering matrix. So, each unit cell of the metasurface exhibits' a dynamic phase response that can be switched between 0° and ?180° by controlling high transmission and total reflection states. Based on this feature, a 1‐bit coding metasurface consisting of discrete codes of “0” and “1” is used to synthesis 3D beams. Hence, tailorable anomalous reflection and diffusion are studied under normal incidence at a fixed frequency of 3.9 THz. This survey opens new opportunities in the domain of Terahertz beam engineering and security scanner applications.     

Numerical Study of the Swirl Effect on a Coaxial Jet Combustor Flame Including Radiative Heat Transfer

A numerical study of the swirl effect on a coaxial jet combustor flame including radiative heat transfer is presented. In this work, the standard k-ε model is applied to investigate the turbulence effect, and the eddy dissipation model (EDM) is used to model combustion. The radiative heat transfer and the properties of gases and soot are considered using a coupled of the finite-volume method (FVM), and the narrow-band based weighted-sum-of-gray gases (WSGG-SNB) model. The results of this work are validated by experiment data. The results clearly show that radiation must be taken into account to obtain good accuracy for turbulent diffusion flame in combustor chamber. Flame is very influenced by the radiation of gases, soot, and combustor wall. However, swirl is an important controlling variable on the combustion characteristics and pollutant formation.