Search results for: Mohamed Nassar

Authors: Mohamed Rashad, Mohamed Hafez, Mohamed Emran, Emad Aboukila, Ibrahim Nassar

Abstract:

Environment-friendly organic wastes of Brewers' spent grain, a byproduct of the brewing process, have recently used as soil amendment to improve soil fertility and plant production. In this work, treatments of 1% (T1) and 2% (T2) of spent grains, 1% (C1) and 2% (C2) of compost and mix of both sources (C1T1) were used and compared to the control for growing Zea mays L. on sandy soil under arid Mediterranean climate. Soils were previously incubated at 65% saturation capacity for a month. The most relevant soil physical and chemical parameters were analysed. Water holding capacity and soil organic matter (OM) increased significantly along the treatments with the highest values in T2. Soil pH decreased along the treatments and the lowest pH was in C1T1. Bicarbonate decreased by 69% in C1T1 comparing to control. Total nitrogen (TN) and available P varied significantly among all treatments and T2, C1T1 and C2 treatments increased 25, 17 and 11 folds in TN and 1.2, 0.6 and 0.3 folds in P, respectively related to control. Available K showed the highest values in C1T1. Soil micronutrients increased significantly along all treatments with the highest values in T2. After corn germination, significant variation was observed in the velocity of germination coefficients (VGC) among all treatments in the order of C1T1>T2>T1>C2>C1>control. The highest records of final germination and germination index were in C1T1 and T2. The spent grains may compensate deficiencies of macro and micronutrients in newly reclaimed sandy soils without adverse effects to sustain crop production with a rider that excessive or continuous use need to be circumvented.

Keywords: corn and squash germination, environmentally friendly organic wastes, soil carbon sequestration, spent grains as soil amendment, water holding capacity

Procedia PDF Downloads 474

Authors: Tarek Aboueldahab, Amin Mohamed Nassar

Abstract:

Wind energy is a fluctuating energy source unlike conventional power plants, thus, it is necessary to accurately predict short term wind speed to integrate wind energy in the electricity supply structure. To do so, we present a hybrid artificial intelligence model of short term wind speed prediction based on passive aggregation of the particle swarm optimization and neural networks. As a result, improvement of the prediction accuracy is obviously obtained compared to the standard artificial intelligence method.

Keywords: artificial intelligence, neural networks, particle swarm optimization, passive aggregation, wind speed prediction

Procedia PDF Downloads 417

Authors: Mohammad Abu Nassar, Mahmoud Al Khalilah, Hussein Abu Nassar

Abstract:

The purpose of this study is to examine whether corporate tax avoidance practices can impact firm value in the Jordanian context. The study employs a quantitative approach using s sample of (124) industrial and services companies listed on the Amman Stock Exchange for the period from 2010 to 2019. Multiple linear regression analysis has been applied to test the study's hypothesis. The study employs effective tax rate and book-tax difference to measure tax avoidance and Tobin's Q factor to measure firm value. The results of the study revealed that tax avoidance practices, when measured using effective tax rates, do not significantly impact firm value. When the book-tax difference is used to measure tax avoidance, the study results showed a negative impact on firm value. The result of the study has not supported the traditional view of tax avoidance as a transfer of wealth from the government to shareholders for industrial and services companies listed on the Amman Stock Exchange, indicating that Jordanian firms should not use tax avoidance strategies to enhance their value.

Keywords: tax avoidance, effective tax rate, book-tax difference, firm value, Amman stock exchange

Procedia PDF Downloads 120

Authors: Michel Zaitouni, Mohamed Nassar

Abstract:

The purpose of this study is first, to explore the effect of employees’ perception of justice on trust in the supervisor in the context of performance appraisal; Second, to assess the role of perceived supervisor support as a mediator between organizational justice and trust in the supervisor in a non-western society such as Kuwait.The survey data consisted of 415 employees working at different hierarchical levels in three major banks in Kuwait. Hierarchical regression analysis was used to test the research hypotheses. Results supported hypothesized relationships between distributive, informational and interpersonal justice and trust in the supervisor but failed to support that procedural justice positively and significantly relate to trust in the supervisor. Moreover, results found that this relationship is partially mediated by perceived supervisor support. A potential limitation of this study is that data were obtained from the same industry which limits the generalizability of this study to other industries. Moreover, a longitudinal research will be helpful to strengthen the mediating relationship. The findings provide valuable information for the development of common perspectives regarding the perception of justice in the context of performance appraisal between the western and non-western societies. The paper has the privilege to explore additional relationships related to justice perceptions in the Kuwaiti banking sector, whereas previous research focused mainly on procedural and distributive justice as predictors of trust in the supervisor.

Keywords: Kuwait, organizational justice, perceived supervisor support, trust in the supervisor

Procedia PDF Downloads 275

Authors: Nour Hassan Ismail, Abdelmonem Nassar, Khaled Baz

Abstract:

Semiconductor crystals smaller than about 10 nm, known as quantum dots, have properties that differ from large samples, including a band gap that becomes larger for smaller particles. These properties create several applications for quantum dots. In this paper, new shapes of quantum dot arrays are used to enhance the photo physical properties of gold nano-particles. This paper presents a study of the effect of nano-particles shape, array, and size on their absorption characteristics.

Keywords: quantum dots, nano-particles, LSPR

Procedia PDF Downloads 447

Authors: Mohamed Abdalla Elamein Boshara, Peter Charles Woods, Nour Eldin Mohamed Elshaiekh

Abstract:

Knowledge Management has become very important for Disaster Management response and planning. This paper proposes the implementation of a Knowledge Management System with a sustainable data collection mechanism for reliable and timely information management to support decision makers in making the right decisions in the timely manner.

Keywords: knowledge management, disaster management, incident tracking, web application

Procedia PDF Downloads 745

Authors: Amr A. EL Hanafy, Yasir Anwar, Saleh A. Mohamed, Saleh Mohamed Saleh Al-Garni, Jamal S. M. Sabir , Osama A. H. Abu Zinadah, Mohamed Morsi Ahmed

Abstract:

In the vicinity of the red sea about 15 fungi species were isolated from oil contaminated sites. On the basis of aptitude to degrade the crude oil and DCPIP assay, two fungal isolates were selected amongst 15 oil degrading strains. Analysis of ITS-1, ITS-2 and amplicon pyrosequencing studies of fungal diversity revealed that these strains belong to Penicillium and Aspergillus species. Two strains that proved to be the most efficient in degrading crude oil was Aspergillus niger (54 %) and Penicillium commune (48 %) Subsequent to two weeks of cultivation in BHS medium the degradation rate were recorded by using spectrophotometer and GC-MS. Hence, it is cleared that these fungal strains has the capability of degradation and can be utilized for cleaning the Saudi Arabian environment.

Keywords: fungal strains, hydrocarbon contaminants, molecular identification, biodegradation, GC-MS

Procedia PDF Downloads 489

Authors: Mohamed Saïd Kahaleras, François Lanzetta, Mohamed Khan, Guillaume Layes, Philippe Nika

Abstract:

This paper presents an experimental work to characterize the dynamic operation of a metal regenerator crossed by dry compressible air alternating flow. Unsteady dynamic measurements concern the pressure, velocity and temperature of the gas at the ends and inside the channels of the regenerator. The regenerators are tested under isothermal conditions and thermal axial temperature gradient.

Keywords: friction factor, oscillating flow, regenerator, stirling machine

Procedia PDF Downloads 472

Authors: Abdallah Mohamed Kamel Mohamed Ali, Samah Saad Zahran, Mohamed Hamed Rashad

Abstract:

Background: Flexible flatfoot (FFF) has been considered as a risk factor for several lower limb injuries and mechanical low back pain. This was attributed to the dysfunction of the lumbopelvic-hip complex musculature. Objective: To investigate the influence of FFF on electromyographic activities of erector spinae and multifidus. Methods: A cross-section study was held between an FFF group (20 subjects) and a normal foot group (20 subjects). A surface electromyography was used to assess the electromyographic activity of erector spinae and multifidus. Group differences were assessed by the T-test. Results: There was a significant increase in EMG activities of erector spinae and multifidus in the FFF group compared with the normal group. Conclusion: There is an increase in EMG activities in erector spinae and multifidus in FFF subjects compared with normal subjects.

Keywords: electromyography, flatfoot, low back pain, paraspinal muscles

Procedia PDF Downloads 180

Authors: Mohammed Y. Abdellah, Mohamed K. Hassan, A. F. Mohamed, Shadi M. Munshi, A. M. Hashem

Abstract:

Pips made from glass fiber reinforced polymer has competitive role in petroleum industry. The need of evaluating the mechanical behavior of (GRP) pipes is essential objects. Stress relaxation illustrates how polymers relieve stress under constant strain. Static relaxation test is carried out at room temperature. The material gives poor static relaxation strength, two loading cycles have been observed for the tested specimen.

Keywords: GRP, sandwich composite material, static relaxation, stress relief

Procedia PDF Downloads 593

Authors: Mohamed Driouich, Kamal Gueraoui, Mohamed Sammouda

Abstract:

The main objective of this work is to establish a numerical code for studying the flow of molten polymers in deformable pipes. Using an iterative numerical method based on finite differences, we determine the profiles of the fluid velocity, the temperature and the apparent viscosity of the fluid. The numerical code presented can also be applied to other industrial applications.

Keywords: numerical code, molten polymers, deformable pipes, finite differences

Procedia PDF Downloads 537

Authors: Shimaa M. Elsaeed, Reem K. Farag, Ibrahim M. Nassar

Abstract:

Hydrogel conductive polymer nanocomposite fabricated via in-situ polymerization of polyaniline (PANI) inside thermosensitive hydrogels based on hydroxy ethyl meth acrylate (HEMA) copolymer with 2-acrylamido-2-methyl propane sulfonic acid (AMPS). SEM micrographs show the nanometric size of the conductive material (polyaniline, PANI) dispersed in the hydrogel matrix. The swelling parameters of hydrogel are measured. The incorporation of PANI improves the mechanical properties and swelling up to 30,000% without breaking. X-ray diffraction shows that typical polyaniline crystallization is formed in composite, which is advantageous to increase the electrical conductivity of the composite hydrogel. Open-circuit voltage (I-V) curve fill factor of the highest photo-conversion efficiency and enhanced to use in solar cell.

Keywords: hydrogel, solar cell, conductive polymer, nanocomposite

Procedia PDF Downloads 364

Authors: Rasha S. Kamal, Nehal S. Ahmed, Amal M. Nassar, Nour E. A. Abd El-Sattar

Abstract:

In the present work, some lube oil antioxidants based on ester of some aromatic thiourea derivative were prepared by two steps: the first step is the reaction of succinyl chloride with ammonium thiocyanate in addition to anthranilic acid as three component system to prepare thiourea derivative (A); the second step is esterification of compound (A) by different alcohol (decyl C₁₀, tetradecyl C₁₄, and octadecyl C₁₈) alcohol. The structures of the prepared compounds were confirmed by infra-red spectroscopy, nuclear magnetic resonance, elemental analysis and determination of the molecular weights. All the prepared compounds were soluble in lube oil. The efficiency of the prepared compounds as antioxidants lube oil additives was investigated and it was found that these prepared compounds give good result as lube oil antioxidant.

Keywords: antioxidant lube oil, three component system, aromatic thiourea derivatives, esterification

Procedia PDF Downloads 214

Authors: Amal M. Nassar, Nehal S. Ahmed, Rasha S. Kamal

Abstract:

Some lube oil additives improve the base oil performance such as viscosity index improvers and pour point depressants which are the most important type of additives. In the present work, some homopolymeric additives were prepared by esterification of acrylic acid with different alcohols (1-dodecyl, 1-hexadecyl, and 1-octadecyl )and then homopolymerization of the prepared esters with different ratio of benzoyl peroxide catalyst (0.25%& 0.5 % and 1%). Structure of the prepared esters was confirmed by Infra-Red Spectroscopy. The molecular weights of the prepared homopolymers were determined by using Gel Permeation Chromatograph. The efficiency of the prepared homopolymers as viscosity index improvers and pour point depressants for lube oil was the investigation. It was found that all the prepared homopolymers are effective as viscosity index improvers and pour point depressants.

Keywords: lube oil additives, homopolymerization, viscosity index improver, pour point depressant

Procedia PDF Downloads 189

Authors: Yousif Mohamed Y. Abdallah, Eltayeb Wagi Allah Eltayeb, Mohamed E. Gar-elnabi, Mohamed Ahmed Ali

Abstract:

To characterize coronary artery obstruction and related findings in ischemic heart patients using cardiac scintigraphy for the identification of myocardial ischemia, 146 patients were studied at basal conditions and also asked for fasting after night till the intravenous injection of the radiopharmaceutical. After the injection time about 15 to 20 minutes, the patient should eat a fatty meal and chocolate for the good excretion of the gall bladder, to evaluate the performance and regional wall motion of the left ventricle (LV). The results showed that the body mass index percentage in this sample was in range of 43.05 to 61.05. The number of patients who were catheter candidates were 56 with 43% and the patients that were not candidate to cathode were 74 patients with 57% of all patients. For the group of patients where type of ischemia was assessed, 29.5% of patients had reversible posterior and inferior wall, 15.1% of patients had fixed large from apex to base, 9.6% of patients had mild basal inferior wall, 4.8 % of patients had mild anterior wall, 6.2% of patients had antro-septal and 34.9% of patients had moderate ischemia.

Keywords: myocardial ischemia, myocardial scintigraphy, contrast ventriculography, coronary artery obstruction

Procedia PDF Downloads 537

Authors: Noura Shehab-Eldeen, Mohamed Elsherbeeny, Hossam Elmetwally, Mohamed Salama, Ahmed Lotfy, Mohamed Elgamal, Hussein Sheashaa, Mohamed Sobh

Abstract:

Mitochondrial toxins including papaverine may be implicated in the etiology and pathogenesis of Parkinson's disease. The aim was to detect the effect of papaverine on the proliferation and viability of neural stem cells. Rat neural progenitor cells were isolated from embryos (E14) brains. The dispersed tissues were allowed to settle, then, The supernatant was centrifuged at 1,000 g for 5 min. The pellet was placed in Hank’s solution cultured as free-floating neurospheres Dulbecco’s modified Eagle medium (DMEM) and Hams F12 (3:1) supplemented with B27 (Invitrogen GmBH, Karlsruhe, Germany), 20 ng/mL epidermal growth factor (EGF; Biosource, Karlsruhe, Germany), 20 ng/mL recombinant human fibroblast growth factor (rhFGF; R&D Systems, Wiesbaden-Nordenstadt, Germany), and penicillin and streptomycin (1:100; Invitrogen) at 37°C with 7.5% CO2 . Differentiation was initiated by growth factor withdrawal and plating onto a poly-d-lysine/ laminin matrix. The neurospheres were fed every 2-3 days by replacing 50% of the culture media with fresh media. The culture suspension was transferred to a dish containing 16 wells. The wells were divided as follows: 4 wells received no papaverine (control), 4 wells 1 u, 4 wells 5 u and 4 wells 10 u of papaverine solution. In the next 2 weeks, photography (0,4,5,11days) and viability test were done. The photographs were analysed. Results : papaverine didn't affect proliferation of neurospheres, while it affected viability compared to control , this was dose related. Conclusion: This indicates the harmful effect of papaverine suggesting it to be a candidate neurotoxin causing Parkinsonism.

Keywords: neurospheres, neural stem cells, papaverine, Parkinsonism

Procedia PDF Downloads 631

Authors: Medjram Sofiane, Babahenini Mohamed Chaouki, Mohamed Benali Yamina

Abstract:

Skin detection is an important task for computer vision systems. A good method for skin detection means a good and successful result of the system. The colour is a good descriptor that allows us to detect skin colour in the images, but because of lightings effects and objects that have a similar colour skin, skin detection becomes difficult. In this paper, we proposed a method using the YCbCr colour space for skin detection and lighting effects elimination, then we use the information of texture to eliminate the false regions detected by the YCbCr colour skin model.

Keywords: skin detection, YCbCr, GLCM, texture, human skin

Procedia PDF Downloads 418

Authors: Chebaani Mohamed, Gplea Amar, Benchouia Mohamed Toufik

Abstract:

Direct torque control is characterized by the merits of fast response, simple structure and strong robustness to the motor parameters variations. This paper proposes the implementation of DTC-SVM of an induction motor drive using Predictive controller. The principle of the method is explained and the system mathematical description is provided. The derived control algorithm is implemented both in the simulation software MatLab/Simulink and on the real induction motor drive with dSPACE control system. Simulated and measured results in steady states and transients are presented.

Keywords: induction motor, DTC-SVM, predictive controller, implementation, dSPACE, Matlab, Simulink

Procedia PDF Downloads 479

Authors: Halimi Mohamed Taher, Kordoghli Bassem, Ben Hassen Mohamed, Sakli Faouzi

Abstract:

Textile and clothing manufacturing industry is based largely on subcontracting system. Choosing the right subcontractor became a strategic decision that can affect the financial position of the company and even his market position. Subcontracting firms in Tunisia are lead to define an appropriate selection process which takes into account several quantitative and qualitative criteria. In this study, a methodology is proposed that includes a Fuzzy Analytic Hierarchy Process (AHP) in order to incorporate the ambiguities and uncertainties in qualitative decision. Best subcontractors for two Tunisian firms are determined based on model results.

Keywords: AHP, subcontractor, multicriteria, selection

Procedia PDF Downloads 654

Authors: Zaidour Mohamed, Ghalem Ali Jr., Achit Henni Mohamed

Abstract:

This project is destined to study pole junctions of reinforced concrete beams subjected to seismic loads. A literature review was made to clarify the work done by researchers in the last three decades and especially the results of the last two years that were studied for the determination of the method of calculating the transverse reinforcement in the different nodes of a structure. For implementation efforts in the columns and beams of a building R + 4 in zone 3 were calculated using the finite element method through software. These results are the basis of our work which led to the calculation of the transverse reinforcement of the nodes of the structure in question.

Keywords: beam–column joints, cyclic loading, shearing force, damaged joint

Procedia PDF Downloads 519

Authors: Mohamed Amarouayache, Badia Amrouche, Gharbi Akila, Boukadoume Mohamed

Abstract:

This work is devoted to the modeling of DC-DC converter (boost) used for MPPT applications to set conditions of stability. For this, we establish a linear mathematical model of the DC-DC converter with an average small signal model. This model has allowed us to apply conventional linear methods of automation. A mathematical relationship between the duty cycle and the voltage of the panel has been set up. With this relationship we specify the conditions of the stability in closed-loop depending on the system parameters (the elements of storage capacity and inductance, PWM control).

Keywords: MPPT, PWM, stability, criterion of Routh, average small signal model

Procedia PDF Downloads 404

Authors: Hind O. Osman, Tilal Elsaman, Bashir A. Yousef, Esraa Elhadi, Aimun A. E. Ahmed, Eyman Mohamed Eltayib, Malik Suliman Mohamed, Magdi Awadalla Mohamed

Abstract:

Epilepsy is the most common neurological condition and cause of substantial morbidity and mortality. In the present study, the molecular hybridization tool was adopted to obtain six Schiff bases of isatin and adamantane-1-carbohydrazide (18–23). Then, their anticonvulsant activity was evaluated using a pentylenetetrazole- (PTZ-) induced seizure model using phenobarbitone as a positive control. Our findings showed that compounds 18–23 provided significant protection against PTZ-induced seizure, and maximum activities were associated with compound 23. Moreover, all investigated compounds increased the latency of induced convulsion and reduced the duration of epilepsy, with compound 23 being the best. Interestingly, most of the synthesized molecules showed a reduction in neurological symptoms and severity of the seizure. Molecular docking studies suggest GABA-A receptor as a potential target, and in silico ADME screening revealed that the pharmaceutical properties of compound 23 are within the specified limit. Thus, compound 23 was identified as a promising candidate that warrants further drug discovery processes.

Keywords: isatin and adamantane, anticonvulsant activity, PTZ-induced seizure, molecular docking

Procedia PDF Downloads 175

Authors: Mohamed Adel Sennouni, Jamal Zbitou, Benaissa Abboud, Abdelwahed Tribak, Hamid Bennis, Mohamed Latrach

Abstract:

A compact UWB planar antenna fed with a microstrip-line is proposed. The new design is composed of a rectangular patch with symmetric L-shaped slots and fed by 50 Ω microstrip transmission line and a reduced ground-plane which have a periodic slots with an overall size of 47 mm x 20 mm. It is intended to be used in wireless applications that cover the ultra-wideband (UWB) frequency band. A wider impedance bandwidth of around 116.5% (1.875

Keywords: UWB planar antenna, L-shaped slots, wireless applications, impedance band-width, radiation pattern, CST

Procedia PDF Downloads 451

Authors: Sidi Mohamed Mesli, Mohamed Habchi, Mohamed Kotbi, Rafik Benallal, Abdelali Derouiche

Abstract:

Fluoride glasses with a nominal composition of BaMnMF7 (M = FeV assuming isomorphous replacement) have been structurally modelled through the simultaneous simulation of their neutron diffraction patterns by a reverse Monte Carlo (RMC) model and by a Rietveld for disordered materials (RDM) method. Model is consistent with an expected network of interconnected [MF6] polyhedra. The RMC results are accompanied by artificial satellite peaks. To remedy this problem, we use an extension of the RMC algorithm, which introduces an energy penalty term in acceptance criteria. This method is called the Hybrid Reverse Monte Carlo (HRMC) method. The idea of this paper is to apply the (HRMC) method to the title glasses, in order to make a study of the phenomenon nature of order and disorder by displaying and discussing the partial pair distribution functions (PDFs) g(r). We suggest that this method can be used to describe average correlations between components of fluoride glass or similar system.

Keywords: fluoride glasses, RMC simulation, neutron scattering, hybrid RMC simulation, Lennard-Jones potential, partial pair distribution functions

Procedia PDF Downloads 484

Authors: Kamel Zemour, Kada Mohamed Amine Chouhim, Mohamed Mairif, Tadj Eddine Adda Ardjan

Abstract:

Many recent studies show the positive effect of phenolic compounds in olive oil on health. They are known for their biological properties, where they have shown potential activity as an antioxidant, anti-inflammatory, and antimicrobial agents. However, this characteristic is rarely studied in olive oil from different regions of Algeria. Different samples collected from the western region of Algeria were evaluated for their polyphenol content, antioxidant activity, and antimicrobial effect. The obtained results demonstrated that this oil is rich in polyphenols and revealed high antimicrobial activity against Staphylococcus aureus and Escherichia coli. Finally, this study has highlighted the nutritional and pharmaceutical importance of olive oil grown in Algeria.

Keywords: olive oil, polyphenols, antioxidant activity, antimicrobial activity

Procedia PDF Downloads 108

Authors: Ali Akrmi, Mohamed Beji, Ahmed Baklouti, Fatma Djouani, Philippe Lang, Mohamed M. Chehimi

Abstract:

Poly(vinyl chloride) (PVC) is a highly versatile polymer with excellent balance of properties and numerous applications such as water pipes, packaging and polymer materials of importance in the biomedical sector. However, depending on the applications, it is necessary to modify PVC by mixing with a plasticizer; surface modification using plasma, surface grafting or flame treatment; or bulk chemical modification which affects the entire PVC chains at an extent that can be tuned by the polymer chemist. The targeted applications are improvement of chemical resistance, avoiding or limitation of migration of toxic plasticizers, improvement of antibacterial properties, or control of blood compatibility.

Keywords: poly(vinyl chloride), nucleophilic substitution, sulfonylcarbamates, XPS

Procedia PDF Downloads 658

Authors: Mohamed Bakry Mohamed Ali, Mohamed Ehab El-Din Mustafa, Joseph Naiem Sabet Aziz, Sarah Mahmoud Ali Kaooh

Abstract:

Background: Acute lung injury (ALI) is one of the major challenges in intensive care medicine. The most common extrapulmonary cause of ALI is sepsis, accounting more than 30% of the cases in humans. Lipopolysaccharide (LPS) has gained wide acceptance as a clinically relevant model of ALI. Lipopolysaccharide is a glycoprotein forming the major constituent of bacterial endotoxin. Losartan is angiotensin II type 1 (AT1) receptor antagonists. It is widely used for management of hypertension. It was recently suggested that losartan protects against septic ALI. It would thereby prevent LPS-induced ALI. Aim of the work and design of the experiment: This work investigated the injurious effect of lipopolysaccharide (LPS) and ALI on adult male albino rat at 24 hours and 14 days of LPS administration and the possible protective role of losartan pretreatment. LPS has deteriorated animal survival and behavior. It increased lung weight and induced lung histological damage. These changes could be much reduced by the losartan pretreatment. Conclusion: Administration of losartan before LPS could largely reduce these LPS/ ALI induced short and long term alterations. It could be recommended that patients susceptible to developing ALI, as in ICU, should receive a protective dose of angitensin II type 1 (AT1) receptor blocker as losartan.

Keywords: acute lung injury (ALI), lipopolysaccharide (LPS), losartan

Procedia PDF Downloads 566

Authors: Mohamed Idris S. Abozaed, Suliman Mohamed Elrajoubi

Abstract:

Researches and concerns in power quality gained significant momentum in the field of power electronics systems over the last two decades globally. This sudden increase in the number of concerns over power quality problems is a result of the huge increase in the use of non-linear loads. In this paper, power quality evaluation of some distribution networks at Misurata - Libya has been done using a power quality and energy analyzer (Fluke 437 Series II). The results of this evaluation are used to minimize the problems of power quality. The analysis shows the main power quality problems that exist and the level of awareness of power quality issues with the aim of generating a start point which can be used as guidelines for researchers and end users in the field of power systems.

Keywords: power quality disturbances, power quality evaluation, statistical analysis, electrical distribution networks

Procedia PDF Downloads 500

Authors: S. Houcine Habib, B. Elkhalil Hachi, Mohamed Guesmi, Mohamed Haboussi

Abstract:

In this paper, dynamic fracture behaviors of cracked orthotropic structure are modeled using extended finite element method (X-FEM). In this approach, the finite element method model is first created and then enriched by special orthotropic crack tip enrichments and Heaviside functions in the framework of partition of unity. The mixed mode stress intensity factor (SIF) is computed using the interaction integral technique based on J-integral in order to predict cracking behavior of the structure. The developments of these procedures are programmed and introduced in a self-software platform code. To assess the accuracy of the developed code, results obtained by the proposed method are compared with those of literature.

Keywords: X-FEM, composites, stress intensity factor, crack, dynamic orthotropic behavior

Procedia PDF Downloads 532

Authors: Mohamed Montassar Ben Slama, Mohamed Fadel Ladeb, Mohamed Ghanmi, Mohamed Ben Youssef, Fouad Zargouni

Abstract:

The salt province Basin in Northern Tunisia is a complex of late Triassic to Early Cretaceous rift and sag basins which was inverted during the Tertiary folding. The deposition of evaporitic sediments during the Late Triassic times played a major role in the subsequent tectonic evolution of the basin. Within southern tethyan passive marge, the ductile salt mass shown early mobilization, vertical transport and withdrawal of the evaporites. These movements influenced the sedimentation during the late Jurassic and Early Cretaceous. The evaporites also influenced deformation during the inversion of the basin and the development of the Tertiary and Quaternary folding. In the studied area, the biostratigraphic and tectonic map analysis of the region of Jebel el Asoued / Ragoubet el Mahjbia can resolve between the hypotheses of the diapiric intrusion of the Triassic salt and the lateral spreading of the Triassic salt as salt ‘glacier’. Also the variation in thickness and facies of the Aptian sediments demonstrates the existence of continental rise architecture at the Aptian time. The observation in a mappable outcrop of the extension segment of the graben fault of Bou Arada on the one hand confirms the existence of a Cretaceous extensive architecture and the tectonic inversion during the Tertiary time has not filled the main game distension. The extent of our observations of Triassic/Aptian and Triassic/Early Campanian contacts, we propose a composite salt ‘glacier’ model as the structures recorded in the Gulf of Mexico in the subsurface and in the Ouenza east Algeria and in Tunisia within Fedj el Adoum, Touiref-Nebeur and Jebel Ech Cheid in the outcrops.

Keywords: Cretaceous rift, salt ‘glassier’, tertiary folding, Tunisia

Procedia PDF Downloads 347