The increasing demand for green spaces in cities underscores the urgent need for sustainable solutions to reduce the ecological impact of urban areas.This research focuses on converting unused rooftops into extensive ...The increasing demand for green spaces in cities underscores the urgent need for sustainable solutions to reduce the ecological impact of urban areas.This research focuses on converting unused rooftops into extensive green roofs in Nador,Morocco,offering an innovative approach to enhancing outdoor thermal comfort in this region.Several advanced techniques were used,including photogrammetric restitution(for creating land use maps),integration of light detection and ranging data(for three-dimensional urban modeling),and meteorological data collection(for modeling urban climate conditions).The urban-multiscale-environmental-predictor solar and longwave environmental irradiance geometry(UMEP-SOLWEIG)model was crucial for precisely evaluating the thermal performance of green roofs and their influence on urban microclimates.This model considers considered various parameters,such as the sky view factor,wall height and aspect,and shading conditions,for accurate,comprehensive analysis.Additionally,for accurate,comprehensive analysis,a comparative evaluation was performed between the UMEP-SOLWEIG and ENVI-met models to assess the UMEP SOLWEIG results.The findings were notable,demonstrating a substantial reduction(averaging over 3°C)in the mean radiant temperature on 60%of rooftops,covering 55%of the total surface area.This highlighted the effectiveness of green roofs in improving outdoor thermal comfort.Furthermore,green roofs were closely associated with reductions in air-conditioning energy consumption,with considerable reductions ranging from 17.53%to 43.82%.These savings translated to estimated financial benefits ranging from USD 1.63-4.07 million.These figures clearly verified the notable economic impact of green roofs despite their initially high costs(approximately USD 84.44 million).These potential long-term savings indicated that these investments are financially viable in the long run.The collected data were used to create thermal maps of the area using geographic-information-system tools.A thermal cadaster specific to green roofs was also developed,accessible online through Web mapping.Overall,this approach facilitates decision-making in urban planning by providing visual information on thermal variations,thereby aiding in the precise planning of measures against urban heat and promoting the use of green roofs to reduce environmental impact.展开更多
The development of bio-sourced materials is essential to ensuring sustainable construction;it is considered a locomotive of the green economy.Furthermore,it is an abundant material in our country,to which very little ...The development of bio-sourced materials is essential to ensuring sustainable construction;it is considered a locomotive of the green economy.Furthermore,it is an abundant material in our country,to which very little attention is being given.This work aims to valorize the waste of the trunks of banana trees to be used in construction.Firstly,the physicochemical properties of the fiber,such as the percentage of crystallization and its morphology,have been determined by X-ray diffraction tests and scanning electron microscopy to confirm the potential and the impact of the mode of drying on the quality of the banana fibers,with the purpose to promote the use of this material in construction.Secondly,the results obtained with the gypsum matrix allowed us to note a preponderant improvement in the composite’s thermal properties thanks to the variation of the banana fiber additive.Thirdly,the impact of the nature of the banana fiber distribution(either fiber mixed in matrix or fiber series model)on the flexural and compressive strengths of the composites was studied.The results obtained indicate that the insulation gain reaches up to 40%.It depends on the volume fraction and type of distribution of the banana fibers.However,the thermal inertia of the composites developed,represented by thermal diffusivity and thermal effusivity,was studied.Results indicate a gain of 40%and 25%,respectively,in terms of thermal diffusivity and thermal effusivity of the developed composites compared to plaster alone.Concerning the mechanical properties,the flexural strength depends on the percentage of the volume fraction of banana fibers used,and it can reach 20%more than the flexural strength of plaster;nevertheless,there is a significant loss in terms of the compressive strength of the studied composites.The results obtained are confirmed by the microstructure of the fiber banana.In fact,the morphology of the banana fibers was improved by the drying process.It reduces the amorphous area and improves the cellulosic crystalline surfaces,which assures good adhesion between the fiber and the matrix plaster.Finally,the dimensionless coefficient analysis was done to judge the optimal proportion of the banana fiber additive and to recommend its use even on false ceilings or walls.展开更多
Creating sustainable cities is the only way to live in a clean environment,and this problem can be solved by using bio-sourced and recycled materials.For this purpose,the authors contribute to the valuation of sheep w...Creating sustainable cities is the only way to live in a clean environment,and this problem can be solved by using bio-sourced and recycled materials.For this purpose,the authors contribute to the valuation of sheep wool waste as an eco-friendly material to be used in insulation.The paper investigates the thermal,hygrothermal,and biological aspects of sheep wool by testing a traditional treatment.The biological method of aerobic mesophilicflora has been applied.Fluorescence X was used to determine the chemical composition of the materials used.Also,thermal characterization has been conducted.The thermal conductivity is above 0.046(W·m^(-1)·K^(-1))and the thermal diffusivity is 1.56.10^(-6) m^(2)·s^(-1).Besides,the energy efficiency of using sheep wool in buildings was studied.Furthermore,its humidity behavior was evaluated in different aspects in both winter and summer.Results of biological analyses show the efficiency of the treatment by removing the majority of the microorgan-isms:the value of yeast and mildew was reduced from 38.10^(2) to 2.10^(2)(UFC·g^(-1)).In addition to that,sheep wool permits obtaining a low thermal transmittance on the scale of the walls and low cooling needs on the scale of the building with a gain of 45%and 52%,respectively.展开更多
A bacterial field isolate recovered from infected tomato plants in a green-house at Sidi Rehal, a region near Casablanca city (Morocco), was identified as the gammaproteobacterium Pseudomonas syringae pv. tomato DC300...A bacterial field isolate recovered from infected tomato plants in a green-house at Sidi Rehal, a region near Casablanca city (Morocco), was identified as the gammaproteobacterium Pseudomonas syringae pv. tomato DC3000 strain, the causal agent of bacterial speck. The bacterial isolate was characterized by morphological, biochemical and molecular biological tests, its growth curves carried out in various culture media, and its phytopathogenicity verified by infection tests. A screening was performed to evaluate the antibacterial activity of methanolic extracts of 12 selected Moroccan plants against the P. syringae pv. tomato DC3000 isolate, and Agar-well diffusion and Broth microdilution methods were used to determine minimum inhibitory and minimum bactericidal concentrations. Among the methanolic extracts tested, only those of Nigella sativa, Geranuim robertianum, Aizoon canariense and Rubia peregrine showed clear inhibitory and bactericidal activities, although the highest values were achieved with N. sativa, a plant used in Morocco as a spice, condiment and medicinal treatment.展开更多
Obviously, the outside annual climate change caused either by a major solar input during the hottest period or by a temperature drop during the coldest period leads to discomfort in inside buildings. This effect can b...Obviously, the outside annual climate change caused either by a major solar input during the hottest period or by a temperature drop during the coldest period leads to discomfort in inside buildings. This effect can be reduced by storing heat transmitted in phase change materials (PCM) as latent heat, in order to ensure a good situation of thermal comfort during all months of the year. In this work, thermal behavior of two roofing systems is studied. One roof is constituted only by usual materials in building. In the other, two phase change materials (PCM) are introduced according to three configurations. Study is interested to assess incorporation effect of two PCMs within the roof and to evaluate the optimum locations to reduce the energy consumption of air-conditioned room. Mono-dimensional numerical model validated analytically and experimentally, is used to carry out a parametric analyzes to determine characteristics of the layers in which the roofs are formed regardless of external climate effect. Numerical calculations are performed for three configurations of roof. Results show that insertion of phase change materials in roof provides best energy consumption saving regardless annual climate change. Generally, the three configurations lead to different results, depending on the combination of PCMs. This difference becomes less important when selection of PCMs take account the thermal comfort level and temperatures of hottest and coldest periods.展开更多
Energy efficiency in buildings is today a prime objective for energy policy at national and international levels. Because the residential and commercial energy consumption has steadily increased reaching figures betwe...Energy efficiency in buildings is today a prime objective for energy policy at national and international levels. Because the residential and commercial energy consumption has steadily increased reaching figures between 20% and 40%. The use of thermal insulation of the building envelope is one of the most currently requested solutions to reduce this energy consumption. Phase Change Materials (PCM) have received increased attention due to their ability to store large amounts of thermal energy within narrow temperature ranges. This property makes them ideal for storage of passive heat in the building envelopes. An experimental study was conducted to analyze the influence of PCM in the construction of exterior walls. Two test cells are constructed in the Faculty of Science Ain Chock, Casablanca. One is equipped with a 0.56 cm layer of PCM on its roof while the second is a reference cell without PCM. The results presented for the period from 8th to 10<sup>th</sup> July 2014 show that the integration of PCM layer reduces the amplitude of instantaneous heat flux through the horizontal wall. The indoor and the internal vertical wall temperatures, in the case of the cell with PCM, are relatively decreased compared to those of the reference one. For example, the maximum deviation between the indoor temperatures of the cubicles is not more than 1.5℃ while the one on the west faces reaches 3℃ by mid day. Also the inclusion of a layer of PCM shifts the time of peak load and discharge.展开更多
One of the difficulties encountered in the study of dusty plasmas is related to the knowledge of the size of the dust particles present. A variety of sources, physical and chemical mechanisms of formation, causes a wi...One of the difficulties encountered in the study of dusty plasmas is related to the knowledge of the size of the dust particles present. A variety of sources, physical and chemical mechanisms of formation, causes a wide variety of sizes and morphologies of dust. The diameter of a dust will not be unique but spread over several orders of magnitude. Its distribution in number, surface, mass or volume is called distribution. It is important to know this distribution in particle size because it strongly impacts the physical and radiative processes. To have a dust distribution in situ is very difficult;the reverse method can identify the particle populations from light extinction measures. In this study, we present an inversion procedure with a Tikhonov regularization dedicated to the determination of volume size distribution (V-PSD) from extinction measurements corresponding to the different wavelengths obtained by the Extinction Spectrometry technique.展开更多
Nanofluids are considered to offer important advantages over conventional heat transfer fluids. A model is developed to analyze the behavior of nanofluids taking into account the solid fraction χ. The Navier-Stokes e...Nanofluids are considered to offer important advantages over conventional heat transfer fluids. A model is developed to analyze the behavior of nanofluids taking into account the solid fraction χ. The Navier-Stokes equations are solved numerically with Alternating Direct Implicit method (ADI method) for various Grashof numbers 104 and 105;we have an excellent agreement between our numerical code and previously published works. Copper-Water nanofluid is used with Pr = 6.2 and solid volume fraction χ is varied as 0%;5%;10%;15% and 20%. The problem considered is a two-dimensional heat transfer in a square cavity. The vertical walls are differentially heated, the left is maintained at hot con- dition (sinusoidal) when the right one is cold. The horizontal walls are assumed to be insulated, non conducting and impermeable to mass transfer. The nanofluid in the enclosure is Newtonian, incompressible and laminar. The nanopar- ticles are assumed to have a uniform shape and size. Moreover, it is assumed that both the fluid phase and nanoparticles are in thermal equilibrium state and they flow at the same velocity. The thermophysical properties of the nanofluid are assumed to be constant except for the density variation in the buoyancy force, which is based on the Boussinesq approximation. Different correlations are proposed for predicting heat transfer for uniform and sinusoidal boundary thermal conditions.展开更多
The work deals with the thermal behavior of a conventional partition wall incorporating a phase change material(PCM).The wall separates two environments with different thermal properties.The first one is conditioned,w...The work deals with the thermal behavior of a conventional partition wall incorporating a phase change material(PCM).The wall separates two environments with different thermal properties.The first one is conditioned,while the adjacent space is characterized by a temperature that changes sinusoidally in time.The effect of the PCM is assessed through a comparative analysis of the cases with and without PCM.The performances are evaluated in terms of dimensionless energy stored within the wall,comfort temperature and variations of these quantities as a function of the amount of PCM and its emplacement.展开更多
A phenomenological low-filed mobility model is developed to describe the dependence ot the carrier molgmty on me gate to source bias applied for AIGaN/GaN high electron mobility transistor. The results show excellent ...A phenomenological low-filed mobility model is developed to describe the dependence ot the carrier molgmty on me gate to source bias applied for AIGaN/GaN high electron mobility transistor. The results show excellent agreement with experimental data, when compared thereby proving the validity of the model. In the proposed work the temporal evolution of the mobility degradation shows a sharp decline in emission rates below 456 s-1. We also note a sharp decline for large defects densities.展开更多
The glass series<span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span s...The glass series<span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">50P<sub>2</sub>O<sub>5</sub>-25CaO-(25</span></span><span style="white-space:normal;"><span style="font-family:;" "="">-</span></span><span style="white-space:normal;"><span style="font-family:;" "="">x)Na<sub>2</sub>O-xCoO (with (0 ≤ x ≤ 25;mol%)</span></span><span style="white-space:normal;"><span style="font-family:;" "="">, has been prepared by direct melting at 1080<span style="white-space:nowrap;">°</span>C</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">±</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">20<span style="white-space:nowrap;">°</span>C</span></span><span style="white-space:normal;"><span style="font-family:;" "="">. The introduction</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">of cobalt in calcium phosphate glasses is use</span></span><span style="white-space:normal;"><span style="font-family:;" "="">d</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> to compare its</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">effect with calcium in inhibition corrosion. The dissolution rate has been investigated. It indicated an improvement of chemical durability when the cobalt oxide increases in the network glass at the expense of Na<sub>2</sub>O content. Both, IR spectroscopy and X-ray diffraction have confirmed the structure changes when the CoO content increases in the glass. This change results in the disappearance of isolated orthophosphate groups follow</span></span><span style="white-space:normal;"><span style="font-family:;" "="">ed</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">of a polymerizing of the structure from isolated orthophosphate towards pyrophosphate chains (Q<sup>1</sup>) by promoting the formation of olygophosphates</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">(mixed</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">Q<sup>1</sup>-Q<sup>2</sup>) </span></span><span style="white-space:normal;"><span style="font-family:;" "="">rich in pyrophosphates. Analysis of the density values, showed an increase of density with the increase CoO content. The covalent radius values of oxygen</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><i><span style="font-family:;" "="">r</span></i></span><span style="white-space:normal;"><sub><span style="font-family:;" "="">cal</span></sub></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">(O<sup>2-</sup>) indicate a significant decrease and therefore a relatively high reinforcement of the metal-oxygen-phosphorus (Co-O-P) bonds. SEM micrograph confirms the evolution of the glass structural morphology. The sample having a maximum CoO content confirms a homogeneous glass phase with quite crystalline particles.</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">This property is prerequisite for many interesting industrial applications.</span></span>展开更多
Inorganic pyrophosphatases are enzymes that catalyze the hydrolysis of inorganic pyrophosphate to orthophosphate. These enzymes are divided into two groups: the soluble pyrophosphatases and the membrane pyrophosphatas...Inorganic pyrophosphatases are enzymes that catalyze the hydrolysis of inorganic pyrophosphate to orthophosphate. These enzymes are divided into two groups: the soluble pyrophosphatases and the membrane pyrophosphatases. They vary in structure and each has a determined catalysis mechanism. Soluble pyrophosphatases are ubiquitous enzymes and play a key role in regulating the rate of pyrophosphate and balance in this sense, the biosynthetic reactions. Membrane pyrophosphatases are ion pumps, producing a proton or sodium gradient, and provide critical energy reserves to organisms, especially during stress conditions. Several studies have shown that these enzymes are involved in numerous disorders (diseases, fault cell growth···). However they are potential targets for the development of agents against parasites. This article consists of a description of the different types, structures, catalytic properties of inorganic pyrophosphatases and their involvement in cellular metabolism.展开更多
Phosphorus is one of the bioelements most needed as a compound cell by living organisms. Phosphorus is involved in several pathologies: in human with bone and kidney diseases, in mammals with metabolism disorder (gluc...Phosphorus is one of the bioelements most needed as a compound cell by living organisms. Phosphorus is involved in several pathologies: in human with bone and kidney diseases, in mammals with metabolism disorder (glucose, insulin···), in microorganisms whose phosphorus is involved in cell growth. Phosphorus has various forms including pyrophosphate, a by-product of multiple pathways of biosynthesis. Enzymes that hydrolyze pyrophosphate are called inorganic pyrophosphatases (PPases). Two major types of inorganic pyrophosphatases are distinguished: the soluble pyrophosphatases (sPPases) and the membrane pyrophosphatases (mPPases or H+/Na+-PPases). They play a key role in the control of intracellular inorganic pyrophosphate level and produce an important ions gradient (H+ or Na+) to the cells. In this work, we primarily focused on the physiological study in a phosphate-poor medium of two models Tetrahymena thermophile and Tetrahymena pyriformis, following the mobility, the growth and the morphology of cells. Secondly, we evaluated the enzymatic activity of soluble and membrane pyrophosphatases in both species grown in the same complex medium. A decrease of cell growth is correlated with unusual morphologies and different mobility in the stress medium. The measurement of soluble and membrane inorganic pyrophosphatases activities also shows a decrease which illustrates the lack of phosphate found in the stress medium. Deficiency of phosphate is a limiting factor for protozoan growth. These results indicate that Tetrahymena can be used as a model of cellular stress and consists of a target to study inorganic pyrophosphatases for a better understanding of phosphate cycle in higher organisms.展开更多
The future network world will be embedded with different generations of wireless technologies,such as 3G,4G and 5G.At the same time,the development of new devices equipped with multiple interfaces is growing rapidly i...The future network world will be embedded with different generations of wireless technologies,such as 3G,4G and 5G.At the same time,the development of new devices equipped with multiple interfaces is growing rapidly in recent years.As a consequence,the vertical handover protocol is developed in order to provide ubiquitous connectivity in the heterogeneous wireless environment.Indeed,by using this protocol,the users have opportunities to be connected to the Internet through a variety of wireless technologies at any time and anywhere.The main challenge of this protocol is how to select the best access network in terms of Quality of Service(QoS)for users.For that,many algorithms have been proposed and developed to deal with the issue in recent studies.However,all existing algorithms permit only the selection of one access network from the available networks during the vertical handover process.To cope with this problem,in this paper we propose a new approach based on k-partite graph.Firstly,we introduce k-partite graph theory to model the vertical handover problem.Secondly,the selection of the best path is performed by a robust and lightweight mechanism based on cost function and Dijkstra’s algorithm.The experimental results show that the proposed approach can achieve better performance of QoS than the existing algorithms for FTP traffic and video streaming.展开更多
Oued El Maleh watershed is considered the largest ocean basin of the Chaouia-Ouardigha region in Morocco. Severe flooding occurred in 1996, 2001 and 2002 in the watershed. Thus, significant economic and human damage h...Oued El Maleh watershed is considered the largest ocean basin of the Chaouia-Ouardigha region in Morocco. Severe flooding occurred in 1996, 2001 and 2002 in the watershed. Thus, significant economic and human damage has been caused. The floods of Mohammedia city, located in the outlet of the watershed, were due to the silting of the Oued El Maleh dam which has lost its ability to retain water. This work, therefore, aims to assess soil losses by water erosion in the Oued El Maleh watershed through modeling main factors involved in water erosion. The methodology used is based on the use of the universal soil loss equation (USLE). The model includes the following factors: soil erodibility, the inclination of slopes, the rainfall erosivity, vegetation cover and erosion control practices. The aggressiveness of rainfall was calculated for a number of stations bordering the study area and interpolated across the watershed using geostatistical model. Soil erodibility was extracted from soil map and soil survey. The effect of topography was approached by combining the degree of slope and slope length using a digital elevation model (ASTER) and ArcHydrology extension (ArcGIS). The vegetation cover was derived from Landsat image ETM through the supervised classification method. The index of erosion control practices was approached by field visits. All factors have been measured and integrated into a geographic information system which enabled us to spatialize the degree of sediment production at the watershed scale in a synthetic map. The annual soil loss is 8.21 t/ha/yr and the soil loss classification shows that surfaces affected by high erosion are equivalent to 10% of the watershed. Furthermore, this map is available to support land managers policy makers in the process of decision making related to soil conservation, infrastructure and citizens’ property protection.展开更多
A study on the assemblage composition and vertical distribution of larval fish was conducted in the southern area of the Moroccan Atlantic coast in Autumn 2011. A total of I 680 fish larvae taxa were identified from 2...A study on the assemblage composition and vertical distribution of larval fish was conducted in the southern area of the Moroccan Atlantic coast in Autumn 2011. A total of I 680 fish larvae taxa were identified from 21 families. The majority of the larvae were present in the upper layers. Clupeids were the most abundant larvae taxa followed by Myctophidae, Gadidae and Sparidae, hence the larval fish assemblages (LFA) were variable in different depth layers. Total fish larvae showed a preference for surface layers, and were mainly found above 75 m depth, with some exceptions. The maximum concentration of fish larvae was concentrated up to 25 m essentially above the thermocline, where chlorophyll a and mesozooplankton were abundant. Spatially, neritic families were located near the coast and at some offshore stations especially in the northern part, while oceanic families were more distributed towards offshore along the study area. Cluster analysis showed a segregation of two groups of larvae. However, a clear separation between neritic families and oceanic families was not found. Multivariate analysis highlighted the relationship between the distribution of larvae of different families and environmental parameters. Temperature and salinity seem to have been the factors that acted on associations offish larvae. Day/night vertical distributions suggest there was not a very significant vertical migration, probably due to adequate light levels for feeding.展开更多
Staphylococcus aureus is one of the main pathogenic agents responsible for nosocomial and community-acquired bacterial infections. The pathogenicity of this Gram-positive bacterium is ensured by its different adhesion...Staphylococcus aureus is one of the main pathogenic agents responsible for nosocomial and community-acquired bacterial infections. The pathogenicity of this Gram-positive bacterium is ensured by its different adhesion factors. Collagen and the extracellular glycoprotein adhesin are among the Staphylococcus most important virulence factors. It has been shown that most of the S. aureus strains carry the ica operon, responsible for biofilm production. However, the coexpression of the icaA and the icaD genes is necessary for complete biofilm synthesis. The aim of our study was to study a collection of 15 clinical strains of S. aureus from different sources for the presence of can and icaD genes coding intercellular adhesion proteins. We also intended to estimate the strains’ ability to form biofilms by the red Cong method and to test the adhesion ability of S. aureus to the ciliated protist Tetrahymena pyriformis, which we used as a novel cellular adhesion model. Finally, we checked the adhesion’s inhibition capacity of some plants extracts. The molecular detection of adhesion genes revealed that 80% of strains are cna positive, and 73% are icaD positive. Qualitative biofilm production of S. aureus revealed that 66.6% of strains were slime producers. The adhesion test revealed that 20% of strains are strongly adhering to T. pyriformis and that the Clematis cirrhosa extract has an anti-adhering effect of S. aureus to the ciliate T. pyriformis.展开更多
Maamora is considered the most important cork-oak forest in the world with regard to surface. Therefore, anthropic pressure, including cork harvesting, grazing and soft acorn picking up by local communities, has harmf...Maamora is considered the most important cork-oak forest in the world with regard to surface. Therefore, anthropic pressure, including cork harvesting, grazing and soft acorn picking up by local communities, has harmful consequences on forest regeneration and the forest become older exceeding harvesting age. Thus, its sustainability depends on the managers’ ability to succeed cork oak plantations. This work presents an assessment approach to evaluate Quercus suber suitability to its plantation which is based on a random forest algorithm (RF). In fact, this suitability has been assessed through analyzing management data related to previous plantation success rates (SR). Then a relationship between SR and a set of environmental and social factors has been investigated using the RF. Application of the fitted model to continuous maps of all involved factors enabled establishment of suitability maps which would help managers to make more rational decisions in terms of cork oak regeneration, ensuring Maamora forest sustainability.展开更多
We consider and we study a general concept of domination for controlled and observed distributed systems. We give characterization results and the main properties of this notion for controlled systems, with respect to...We consider and we study a general concept of domination for controlled and observed distributed systems. We give characterization results and the main properties of this notion for controlled systems, with respect to an output operator. We also examine the case of actuators and sensors. Various other situations are considered and applications are given. Then, we extend this study by comparing observed systems with respect to a control operator. Finally, we study the relationship between the notion of domination and the compensation one, in the exact and weak cases.展开更多
In this paper, the MHD peristaltic flow inside wavy walls of an asymmetric channel is investigated, where the walls of the channel are moving with peristaltic wave velocity along the channel length. During this invest...In this paper, the MHD peristaltic flow inside wavy walls of an asymmetric channel is investigated, where the walls of the channel are moving with peristaltic wave velocity along the channel length. During this investigation,the electrical conductivity both in Lorentz force and Joule heating is taken to be temperature dependent. Also, the long wavelength and low Reynolds number assumptions are utilized to reduce the governing partial differential equations into a set of coupled nonlinear ordinary differential equations. The new set of obtained equations is then numerically solved using the generalized differential quadrature method(GDQM). This is the first attempt to solve the nonlinear equations arising in the peristaltic flows using this method in combination with the Newton-Raphson technique. Moreover, in order to check the accuracy of the proposed numerical method, our results are compared with the results of built-in Mathematica command NDSolve. Taking Joule heating and viscous dissipation into account, the effects of various parameters appearing in the problem are used to discuss the fluid flow characteristics and heat transfer in the electrically conducting fluids graphically. In presence of variable electrical conductivity, velocity and temperature profiles are highly decreasing in nature when the intensity of the electrical conductivity parameter is strengthened.展开更多
文摘The increasing demand for green spaces in cities underscores the urgent need for sustainable solutions to reduce the ecological impact of urban areas.This research focuses on converting unused rooftops into extensive green roofs in Nador,Morocco,offering an innovative approach to enhancing outdoor thermal comfort in this region.Several advanced techniques were used,including photogrammetric restitution(for creating land use maps),integration of light detection and ranging data(for three-dimensional urban modeling),and meteorological data collection(for modeling urban climate conditions).The urban-multiscale-environmental-predictor solar and longwave environmental irradiance geometry(UMEP-SOLWEIG)model was crucial for precisely evaluating the thermal performance of green roofs and their influence on urban microclimates.This model considers considered various parameters,such as the sky view factor,wall height and aspect,and shading conditions,for accurate,comprehensive analysis.Additionally,for accurate,comprehensive analysis,a comparative evaluation was performed between the UMEP-SOLWEIG and ENVI-met models to assess the UMEP SOLWEIG results.The findings were notable,demonstrating a substantial reduction(averaging over 3°C)in the mean radiant temperature on 60%of rooftops,covering 55%of the total surface area.This highlighted the effectiveness of green roofs in improving outdoor thermal comfort.Furthermore,green roofs were closely associated with reductions in air-conditioning energy consumption,with considerable reductions ranging from 17.53%to 43.82%.These savings translated to estimated financial benefits ranging from USD 1.63-4.07 million.These figures clearly verified the notable economic impact of green roofs despite their initially high costs(approximately USD 84.44 million).These potential long-term savings indicated that these investments are financially viable in the long run.The collected data were used to create thermal maps of the area using geographic-information-system tools.A thermal cadaster specific to green roofs was also developed,accessible online through Web mapping.Overall,this approach facilitates decision-making in urban planning by providing visual information on thermal variations,thereby aiding in the precise planning of measures against urban heat and promoting the use of green roofs to reduce environmental impact.
文摘The development of bio-sourced materials is essential to ensuring sustainable construction;it is considered a locomotive of the green economy.Furthermore,it is an abundant material in our country,to which very little attention is being given.This work aims to valorize the waste of the trunks of banana trees to be used in construction.Firstly,the physicochemical properties of the fiber,such as the percentage of crystallization and its morphology,have been determined by X-ray diffraction tests and scanning electron microscopy to confirm the potential and the impact of the mode of drying on the quality of the banana fibers,with the purpose to promote the use of this material in construction.Secondly,the results obtained with the gypsum matrix allowed us to note a preponderant improvement in the composite’s thermal properties thanks to the variation of the banana fiber additive.Thirdly,the impact of the nature of the banana fiber distribution(either fiber mixed in matrix or fiber series model)on the flexural and compressive strengths of the composites was studied.The results obtained indicate that the insulation gain reaches up to 40%.It depends on the volume fraction and type of distribution of the banana fibers.However,the thermal inertia of the composites developed,represented by thermal diffusivity and thermal effusivity,was studied.Results indicate a gain of 40%and 25%,respectively,in terms of thermal diffusivity and thermal effusivity of the developed composites compared to plaster alone.Concerning the mechanical properties,the flexural strength depends on the percentage of the volume fraction of banana fibers used,and it can reach 20%more than the flexural strength of plaster;nevertheless,there is a significant loss in terms of the compressive strength of the studied composites.The results obtained are confirmed by the microstructure of the fiber banana.In fact,the morphology of the banana fibers was improved by the drying process.It reduces the amorphous area and improves the cellulosic crystalline surfaces,which assures good adhesion between the fiber and the matrix plaster.Finally,the dimensionless coefficient analysis was done to judge the optimal proportion of the banana fiber additive and to recommend its use even on false ceilings or walls.
文摘Creating sustainable cities is the only way to live in a clean environment,and this problem can be solved by using bio-sourced and recycled materials.For this purpose,the authors contribute to the valuation of sheep wool waste as an eco-friendly material to be used in insulation.The paper investigates the thermal,hygrothermal,and biological aspects of sheep wool by testing a traditional treatment.The biological method of aerobic mesophilicflora has been applied.Fluorescence X was used to determine the chemical composition of the materials used.Also,thermal characterization has been conducted.The thermal conductivity is above 0.046(W·m^(-1)·K^(-1))and the thermal diffusivity is 1.56.10^(-6) m^(2)·s^(-1).Besides,the energy efficiency of using sheep wool in buildings was studied.Furthermore,its humidity behavior was evaluated in different aspects in both winter and summer.Results of biological analyses show the efficiency of the treatment by removing the majority of the microorgan-isms:the value of yeast and mildew was reduced from 38.10^(2) to 2.10^(2)(UFC·g^(-1)).In addition to that,sheep wool permits obtaining a low thermal transmittance on the scale of the walls and low cooling needs on the scale of the building with a gain of 45%and 52%,respectively.
文摘A bacterial field isolate recovered from infected tomato plants in a green-house at Sidi Rehal, a region near Casablanca city (Morocco), was identified as the gammaproteobacterium Pseudomonas syringae pv. tomato DC3000 strain, the causal agent of bacterial speck. The bacterial isolate was characterized by morphological, biochemical and molecular biological tests, its growth curves carried out in various culture media, and its phytopathogenicity verified by infection tests. A screening was performed to evaluate the antibacterial activity of methanolic extracts of 12 selected Moroccan plants against the P. syringae pv. tomato DC3000 isolate, and Agar-well diffusion and Broth microdilution methods were used to determine minimum inhibitory and minimum bactericidal concentrations. Among the methanolic extracts tested, only those of Nigella sativa, Geranuim robertianum, Aizoon canariense and Rubia peregrine showed clear inhibitory and bactericidal activities, although the highest values were achieved with N. sativa, a plant used in Morocco as a spice, condiment and medicinal treatment.
文摘Obviously, the outside annual climate change caused either by a major solar input during the hottest period or by a temperature drop during the coldest period leads to discomfort in inside buildings. This effect can be reduced by storing heat transmitted in phase change materials (PCM) as latent heat, in order to ensure a good situation of thermal comfort during all months of the year. In this work, thermal behavior of two roofing systems is studied. One roof is constituted only by usual materials in building. In the other, two phase change materials (PCM) are introduced according to three configurations. Study is interested to assess incorporation effect of two PCMs within the roof and to evaluate the optimum locations to reduce the energy consumption of air-conditioned room. Mono-dimensional numerical model validated analytically and experimentally, is used to carry out a parametric analyzes to determine characteristics of the layers in which the roofs are formed regardless of external climate effect. Numerical calculations are performed for three configurations of roof. Results show that insertion of phase change materials in roof provides best energy consumption saving regardless annual climate change. Generally, the three configurations lead to different results, depending on the combination of PCMs. This difference becomes less important when selection of PCMs take account the thermal comfort level and temperatures of hottest and coldest periods.
文摘Energy efficiency in buildings is today a prime objective for energy policy at national and international levels. Because the residential and commercial energy consumption has steadily increased reaching figures between 20% and 40%. The use of thermal insulation of the building envelope is one of the most currently requested solutions to reduce this energy consumption. Phase Change Materials (PCM) have received increased attention due to their ability to store large amounts of thermal energy within narrow temperature ranges. This property makes them ideal for storage of passive heat in the building envelopes. An experimental study was conducted to analyze the influence of PCM in the construction of exterior walls. Two test cells are constructed in the Faculty of Science Ain Chock, Casablanca. One is equipped with a 0.56 cm layer of PCM on its roof while the second is a reference cell without PCM. The results presented for the period from 8th to 10<sup>th</sup> July 2014 show that the integration of PCM layer reduces the amplitude of instantaneous heat flux through the horizontal wall. The indoor and the internal vertical wall temperatures, in the case of the cell with PCM, are relatively decreased compared to those of the reference one. For example, the maximum deviation between the indoor temperatures of the cubicles is not more than 1.5℃ while the one on the west faces reaches 3℃ by mid day. Also the inclusion of a layer of PCM shifts the time of peak load and discharge.
文摘One of the difficulties encountered in the study of dusty plasmas is related to the knowledge of the size of the dust particles present. A variety of sources, physical and chemical mechanisms of formation, causes a wide variety of sizes and morphologies of dust. The diameter of a dust will not be unique but spread over several orders of magnitude. Its distribution in number, surface, mass or volume is called distribution. It is important to know this distribution in particle size because it strongly impacts the physical and radiative processes. To have a dust distribution in situ is very difficult;the reverse method can identify the particle populations from light extinction measures. In this study, we present an inversion procedure with a Tikhonov regularization dedicated to the determination of volume size distribution (V-PSD) from extinction measurements corresponding to the different wavelengths obtained by the Extinction Spectrometry technique.
文摘Nanofluids are considered to offer important advantages over conventional heat transfer fluids. A model is developed to analyze the behavior of nanofluids taking into account the solid fraction χ. The Navier-Stokes equations are solved numerically with Alternating Direct Implicit method (ADI method) for various Grashof numbers 104 and 105;we have an excellent agreement between our numerical code and previously published works. Copper-Water nanofluid is used with Pr = 6.2 and solid volume fraction χ is varied as 0%;5%;10%;15% and 20%. The problem considered is a two-dimensional heat transfer in a square cavity. The vertical walls are differentially heated, the left is maintained at hot con- dition (sinusoidal) when the right one is cold. The horizontal walls are assumed to be insulated, non conducting and impermeable to mass transfer. The nanofluid in the enclosure is Newtonian, incompressible and laminar. The nanopar- ticles are assumed to have a uniform shape and size. Moreover, it is assumed that both the fluid phase and nanoparticles are in thermal equilibrium state and they flow at the same velocity. The thermophysical properties of the nanofluid are assumed to be constant except for the density variation in the buoyancy force, which is based on the Boussinesq approximation. Different correlations are proposed for predicting heat transfer for uniform and sinusoidal boundary thermal conditions.
文摘The work deals with the thermal behavior of a conventional partition wall incorporating a phase change material(PCM).The wall separates two environments with different thermal properties.The first one is conditioned,while the adjacent space is characterized by a temperature that changes sinusoidally in time.The effect of the PCM is assessed through a comparative analysis of the cases with and without PCM.The performances are evaluated in terms of dimensionless energy stored within the wall,comfort temperature and variations of these quantities as a function of the amount of PCM and its emplacement.
文摘A phenomenological low-filed mobility model is developed to describe the dependence ot the carrier molgmty on me gate to source bias applied for AIGaN/GaN high electron mobility transistor. The results show excellent agreement with experimental data, when compared thereby proving the validity of the model. In the proposed work the temporal evolution of the mobility degradation shows a sharp decline in emission rates below 456 s-1. We also note a sharp decline for large defects densities.
文摘The glass series<span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">50P<sub>2</sub>O<sub>5</sub>-25CaO-(25</span></span><span style="white-space:normal;"><span style="font-family:;" "="">-</span></span><span style="white-space:normal;"><span style="font-family:;" "="">x)Na<sub>2</sub>O-xCoO (with (0 ≤ x ≤ 25;mol%)</span></span><span style="white-space:normal;"><span style="font-family:;" "="">, has been prepared by direct melting at 1080<span style="white-space:nowrap;">°</span>C</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">±</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">20<span style="white-space:nowrap;">°</span>C</span></span><span style="white-space:normal;"><span style="font-family:;" "="">. The introduction</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">of cobalt in calcium phosphate glasses is use</span></span><span style="white-space:normal;"><span style="font-family:;" "="">d</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> to compare its</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">effect with calcium in inhibition corrosion. The dissolution rate has been investigated. It indicated an improvement of chemical durability when the cobalt oxide increases in the network glass at the expense of Na<sub>2</sub>O content. Both, IR spectroscopy and X-ray diffraction have confirmed the structure changes when the CoO content increases in the glass. This change results in the disappearance of isolated orthophosphate groups follow</span></span><span style="white-space:normal;"><span style="font-family:;" "="">ed</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">of a polymerizing of the structure from isolated orthophosphate towards pyrophosphate chains (Q<sup>1</sup>) by promoting the formation of olygophosphates</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">(mixed</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">Q<sup>1</sup>-Q<sup>2</sup>) </span></span><span style="white-space:normal;"><span style="font-family:;" "="">rich in pyrophosphates. Analysis of the density values, showed an increase of density with the increase CoO content. The covalent radius values of oxygen</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><i><span style="font-family:;" "="">r</span></i></span><span style="white-space:normal;"><sub><span style="font-family:;" "="">cal</span></sub></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">(O<sup>2-</sup>) indicate a significant decrease and therefore a relatively high reinforcement of the metal-oxygen-phosphorus (Co-O-P) bonds. SEM micrograph confirms the evolution of the glass structural morphology. The sample having a maximum CoO content confirms a homogeneous glass phase with quite crystalline particles.</span></span><span style="white-space:normal;"><span style="font-family:;" "=""> </span></span><span style="white-space:normal;"><span style="font-family:;" "="">This property is prerequisite for many interesting industrial applications.</span></span>
文摘Inorganic pyrophosphatases are enzymes that catalyze the hydrolysis of inorganic pyrophosphate to orthophosphate. These enzymes are divided into two groups: the soluble pyrophosphatases and the membrane pyrophosphatases. They vary in structure and each has a determined catalysis mechanism. Soluble pyrophosphatases are ubiquitous enzymes and play a key role in regulating the rate of pyrophosphate and balance in this sense, the biosynthetic reactions. Membrane pyrophosphatases are ion pumps, producing a proton or sodium gradient, and provide critical energy reserves to organisms, especially during stress conditions. Several studies have shown that these enzymes are involved in numerous disorders (diseases, fault cell growth···). However they are potential targets for the development of agents against parasites. This article consists of a description of the different types, structures, catalytic properties of inorganic pyrophosphatases and their involvement in cellular metabolism.
文摘Phosphorus is one of the bioelements most needed as a compound cell by living organisms. Phosphorus is involved in several pathologies: in human with bone and kidney diseases, in mammals with metabolism disorder (glucose, insulin···), in microorganisms whose phosphorus is involved in cell growth. Phosphorus has various forms including pyrophosphate, a by-product of multiple pathways of biosynthesis. Enzymes that hydrolyze pyrophosphate are called inorganic pyrophosphatases (PPases). Two major types of inorganic pyrophosphatases are distinguished: the soluble pyrophosphatases (sPPases) and the membrane pyrophosphatases (mPPases or H+/Na+-PPases). They play a key role in the control of intracellular inorganic pyrophosphate level and produce an important ions gradient (H+ or Na+) to the cells. In this work, we primarily focused on the physiological study in a phosphate-poor medium of two models Tetrahymena thermophile and Tetrahymena pyriformis, following the mobility, the growth and the morphology of cells. Secondly, we evaluated the enzymatic activity of soluble and membrane pyrophosphatases in both species grown in the same complex medium. A decrease of cell growth is correlated with unusual morphologies and different mobility in the stress medium. The measurement of soluble and membrane inorganic pyrophosphatases activities also shows a decrease which illustrates the lack of phosphate found in the stress medium. Deficiency of phosphate is a limiting factor for protozoan growth. These results indicate that Tetrahymena can be used as a model of cellular stress and consists of a target to study inorganic pyrophosphatases for a better understanding of phosphate cycle in higher organisms.
文摘The future network world will be embedded with different generations of wireless technologies,such as 3G,4G and 5G.At the same time,the development of new devices equipped with multiple interfaces is growing rapidly in recent years.As a consequence,the vertical handover protocol is developed in order to provide ubiquitous connectivity in the heterogeneous wireless environment.Indeed,by using this protocol,the users have opportunities to be connected to the Internet through a variety of wireless technologies at any time and anywhere.The main challenge of this protocol is how to select the best access network in terms of Quality of Service(QoS)for users.For that,many algorithms have been proposed and developed to deal with the issue in recent studies.However,all existing algorithms permit only the selection of one access network from the available networks during the vertical handover process.To cope with this problem,in this paper we propose a new approach based on k-partite graph.Firstly,we introduce k-partite graph theory to model the vertical handover problem.Secondly,the selection of the best path is performed by a robust and lightweight mechanism based on cost function and Dijkstra’s algorithm.The experimental results show that the proposed approach can achieve better performance of QoS than the existing algorithms for FTP traffic and video streaming.
文摘Oued El Maleh watershed is considered the largest ocean basin of the Chaouia-Ouardigha region in Morocco. Severe flooding occurred in 1996, 2001 and 2002 in the watershed. Thus, significant economic and human damage has been caused. The floods of Mohammedia city, located in the outlet of the watershed, were due to the silting of the Oued El Maleh dam which has lost its ability to retain water. This work, therefore, aims to assess soil losses by water erosion in the Oued El Maleh watershed through modeling main factors involved in water erosion. The methodology used is based on the use of the universal soil loss equation (USLE). The model includes the following factors: soil erodibility, the inclination of slopes, the rainfall erosivity, vegetation cover and erosion control practices. The aggressiveness of rainfall was calculated for a number of stations bordering the study area and interpolated across the watershed using geostatistical model. Soil erodibility was extracted from soil map and soil survey. The effect of topography was approached by combining the degree of slope and slope length using a digital elevation model (ASTER) and ArcHydrology extension (ArcGIS). The vegetation cover was derived from Landsat image ETM through the supervised classification method. The index of erosion control practices was approached by field visits. All factors have been measured and integrated into a geographic information system which enabled us to spatialize the degree of sediment production at the watershed scale in a synthetic map. The annual soil loss is 8.21 t/ha/yr and the soil loss classification shows that surfaces affected by high erosion are equivalent to 10% of the watershed. Furthermore, this map is available to support land managers policy makers in the process of decision making related to soil conservation, infrastructure and citizens’ property protection.
基金Supported by the Moroccan-Norwegian scientific team that participated in the survey on aboard the R/V Dr Fridtjof Nansen in the context of the regional project CCLME“Canary Current Large Marine Ecosystem”
文摘A study on the assemblage composition and vertical distribution of larval fish was conducted in the southern area of the Moroccan Atlantic coast in Autumn 2011. A total of I 680 fish larvae taxa were identified from 21 families. The majority of the larvae were present in the upper layers. Clupeids were the most abundant larvae taxa followed by Myctophidae, Gadidae and Sparidae, hence the larval fish assemblages (LFA) were variable in different depth layers. Total fish larvae showed a preference for surface layers, and were mainly found above 75 m depth, with some exceptions. The maximum concentration of fish larvae was concentrated up to 25 m essentially above the thermocline, where chlorophyll a and mesozooplankton were abundant. Spatially, neritic families were located near the coast and at some offshore stations especially in the northern part, while oceanic families were more distributed towards offshore along the study area. Cluster analysis showed a segregation of two groups of larvae. However, a clear separation between neritic families and oceanic families was not found. Multivariate analysis highlighted the relationship between the distribution of larvae of different families and environmental parameters. Temperature and salinity seem to have been the factors that acted on associations offish larvae. Day/night vertical distributions suggest there was not a very significant vertical migration, probably due to adequate light levels for feeding.
文摘Staphylococcus aureus is one of the main pathogenic agents responsible for nosocomial and community-acquired bacterial infections. The pathogenicity of this Gram-positive bacterium is ensured by its different adhesion factors. Collagen and the extracellular glycoprotein adhesin are among the Staphylococcus most important virulence factors. It has been shown that most of the S. aureus strains carry the ica operon, responsible for biofilm production. However, the coexpression of the icaA and the icaD genes is necessary for complete biofilm synthesis. The aim of our study was to study a collection of 15 clinical strains of S. aureus from different sources for the presence of can and icaD genes coding intercellular adhesion proteins. We also intended to estimate the strains’ ability to form biofilms by the red Cong method and to test the adhesion ability of S. aureus to the ciliated protist Tetrahymena pyriformis, which we used as a novel cellular adhesion model. Finally, we checked the adhesion’s inhibition capacity of some plants extracts. The molecular detection of adhesion genes revealed that 80% of strains are cna positive, and 73% are icaD positive. Qualitative biofilm production of S. aureus revealed that 66.6% of strains were slime producers. The adhesion test revealed that 20% of strains are strongly adhering to T. pyriformis and that the Clematis cirrhosa extract has an anti-adhering effect of S. aureus to the ciliate T. pyriformis.
文摘Maamora is considered the most important cork-oak forest in the world with regard to surface. Therefore, anthropic pressure, including cork harvesting, grazing and soft acorn picking up by local communities, has harmful consequences on forest regeneration and the forest become older exceeding harvesting age. Thus, its sustainability depends on the managers’ ability to succeed cork oak plantations. This work presents an assessment approach to evaluate Quercus suber suitability to its plantation which is based on a random forest algorithm (RF). In fact, this suitability has been assessed through analyzing management data related to previous plantation success rates (SR). Then a relationship between SR and a set of environmental and social factors has been investigated using the RF. Application of the fitted model to continuous maps of all involved factors enabled establishment of suitability maps which would help managers to make more rational decisions in terms of cork oak regeneration, ensuring Maamora forest sustainability.
文摘We consider and we study a general concept of domination for controlled and observed distributed systems. We give characterization results and the main properties of this notion for controlled systems, with respect to an output operator. We also examine the case of actuators and sensors. Various other situations are considered and applications are given. Then, we extend this study by comparing observed systems with respect to a control operator. Finally, we study the relationship between the notion of domination and the compensation one, in the exact and weak cases.
文摘In this paper, the MHD peristaltic flow inside wavy walls of an asymmetric channel is investigated, where the walls of the channel are moving with peristaltic wave velocity along the channel length. During this investigation,the electrical conductivity both in Lorentz force and Joule heating is taken to be temperature dependent. Also, the long wavelength and low Reynolds number assumptions are utilized to reduce the governing partial differential equations into a set of coupled nonlinear ordinary differential equations. The new set of obtained equations is then numerically solved using the generalized differential quadrature method(GDQM). This is the first attempt to solve the nonlinear equations arising in the peristaltic flows using this method in combination with the Newton-Raphson technique. Moreover, in order to check the accuracy of the proposed numerical method, our results are compared with the results of built-in Mathematica command NDSolve. Taking Joule heating and viscous dissipation into account, the effects of various parameters appearing in the problem are used to discuss the fluid flow characteristics and heat transfer in the electrically conducting fluids graphically. In presence of variable electrical conductivity, velocity and temperature profiles are highly decreasing in nature when the intensity of the electrical conductivity parameter is strengthened.