Search results for: Ahmed Amine Hachicha
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 560

Search results for: Ahmed Amine Hachicha

560 Enhancing the Performance of a Photovoltaic Module Using Different Cooling Methods

Authors: Ahmed Amine Hachicha, Chaouki Ghenai, Abdul Kadir Hamid

Abstract:

Temperature effect on the performance of a photovoltaic module is one of the main concerns that face this renewable energy, especially in hot arid region, e.g. United Arab Emirates. Overheating of the PV modules reduces the open circuit voltage and the efficiency of the modules dramatically. In this work, water-cooling is developed to enhance the performance of PV modules. Different scenarios are tested under UAE weather conditions: front, back and double cooling. A spraying system is used for the front cooling whether a direct contact water system is used for the back cooling. The experimental results are compared to non-cooling module and the performance of the PV module is determined for different situations. The experimental results show that the front cooling is more effective than the back cooling and may decrease the temperature of the PV module significantly. 

Keywords: PV cooling, solar energy, cooling methods, electrical efficiency, temperature effect.

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559 Amine Solution Recovery Package and Controlling Corrosion in Regeneration Tower

Authors: A.Atash J ameh

Abstract:

Sarkhoon gas plant, located in south of Iran, has been installed to removal H2S contained in a high pressure natural gas stream. The solvent used for the H2S removal from gaseous stream is 34% by weight (wt%) Di-ethanol amine (DEA) solutions. Due to increasing concentration of heat stable salt (HSS) in solvent, corrosivity of amine solution had been increased. Reports indicated that there was corrosion on the shell of regeneration column. Because source formation of HSS was unknown, we decided to control the amount of HSS at the limit less than 3% wt amine solvent. Therefore, two small columns were filled by strong anionic base and carbon active, and then polluted amine was passed through beds. Finally a temporary amine recovery package on industrial scale was made based on laboratory’s results. From economical point of view we could save $700000 beside corrosion occurrence of the stripping column has been vigorously decreased.

Keywords: Amines, corrosion, heat stable salt, resin anionic.

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558 Effect of Amine-Functionalized Carbon Nanotubes on the Properties of CNT-PAN Composite Nanofibers

Authors: O. Eren, N. Ucar, A. Onen, N. Kızıldag, O. F. Vurur, N. Demirsoy, I. Karacan

Abstract:

PAN nanofibers reinforced with amine functionalized carbon nanotubes. The effect of amine functionalization and the effect of concentration of CNT on the conductivity and mechanical and morphological properties of composite nanofibers were examined. 1%CNT-NH2 loaded PAN/CNT nanofiber showed the best mechanical properties. Conductivity increased with the incorporation of carbon nanotubes. While an increase of concentration of CNT increases the diameter of nanofiber, the use of functionalized CNT results to decrease of diameter of nanofiber.

Keywords: Amine functionalized carbon nanotube, electrospinning, nanofiber, polyacrylonitrile.

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557 Using Mixed Amine Solution for Gas Sweetening

Authors: Zare Aliabadi, Hassan, Mirzaei, Somaye

Abstract:

The use of amine mixtures employing methyldiethanolamine (MDEA), monoethanolamine (MEA), and diethanolamine (DEA) have been investigated for a variety of cases using a process simulation program called HYSYS. The results show that, at high pressures, amine mixtures have little or no advantage in the cases studied. As the pressure is lowered, it becomes more difficult for MDEA to meet residual gas requirements and mixtures can usually improve plant performance. Since the CO2 reaction rate with the primary and secondary amines is much faster than with MDEA, the addition of small amounts of primary or secondary amines to an MDEA based solution should greatly improve the overall reaction rate of CO2 with the amine solution. The addition of MEA caused the CO2 to be absorbed more strongly in the upper portion of the column than for MDEA along. On the other hand, raising the concentration for MEA to 11%wt, CO2 is almost completely absorbed in the lower portion of the column. The addition of MEA would be most advantageous. Thus, in areas where MDEA cannot meet the residual gas requirements, the use of amine mixtures can usually improve the plant performance.

Keywords: CO2, H2S, Methyldiethanolamine, Monoethanolamine

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556 Carbon Dioxide Removal from Flue Gas Using Amine-Based Hybrid Solvent Absorption

Authors: Supitcha Rinprasertmeechai, Sumaeth Chavadej, Pramoch Rangsunvigit, Santi Kulprathipanja

Abstract:

This study was to investigate the performance of hybrid solvents blended between primary, secondary, or tertiary amines and piperazine (PZ) for CO2 removal from flue gas in terms of CO2 absorption capacity and regeneration efficiency at 90 oC. Alkanolamines used in this work were monoethanolamine (MEA), diethanolamine (DEA), and triethanolamine (TEA). The CO2 absorption was experimentally examined under atmospheric pressure and room temperature. The results show that MEA blend with PZ provided the maximum CO2 absorption capacity of 0.50 mol CO2/mol amine while TEA provided the minimum CO2 absorption capacity of 0.30 mol CO2/mol amine. TEA was easier to regenerate for both first cycle and second cycle with less loss of absorption capacity. The regeneration efficiency of TEA was 95.09 and 92.89 %, for the first and second generation cycles, respectively.

Keywords: CO2 absorption capacity, regeneration efficiency, CO2 removal, flue gas

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555 Removal of CO2 and H2S using Aqueous Alkanolamine Solusions

Authors: Zare Aliabad, H., Mirzaei, S.

Abstract:

This work presents a theoretical investigation of the simultaneous absorption of CO2 and H2S into aqueous solutions of MDEA and DEA. In this process the acid components react with the basic alkanolamine solution via an exothermic, reversible reaction in a gas/liquid absorber. The use of amine solvents for gas sweetening has been investigated using process simulation programs called HYSYS and ASPEN. We use Electrolyte NRTL and Amine Package and Amines (experimental) equation of state. The effects of temperature and circulation rate and amine concentration and packed column and murphree efficiency on the rate of absorption were studied. When lean amine flow and concentration increase, CO2 and H2S absorption increase too. With the improvement of inlet amine temperature in absorber, CO2 and H2S penetrate to upper stages of absorber and absorption of acid gases in absorber decreases. The CO2 concentration in the clean gas can be greatly influenced by the packing height, whereas for the H2S concentration in the clean gas the packing height plays a minor role. HYSYS software can not estimate murphree efficiency correctly and it applies the same contributions in all diagrams for HYSYS software. By improvement in murphree efficiency, maximum temperature of absorber decrease and the location of reaction transfer to the stages of bottoms absorber and the absorption of acid gases increase.

Keywords: Absorber, DEA, MDEA, Simulation.

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554 Integrated Modeling Approach for Energy Planning and Climate Change Mitigation Assessment in the State of Florida

Authors: Kuntal Thakkar, Chaouki Ghenai, Ahmed Hachicha

Abstract:

An integrated modeling approach was used in this study for energy planning and climate change mitigation assessment. The main objective of this study was to develop various green-house gas (GHG) mitigations scenarios in the energy demand and supply sectors for the state of Florida. The Long range energy alternative planning (LEAP) model was used in this study to examine the energy alternative and GHG emissions reduction scenarios for short and long term (2010-2050). One of the energy analysis and GHG mitigation scenarios was developed by taking into account the available renewable energy resources potential for power generation in the state of Florida. This will help to compare and analyze the GHG reduction measure against “Business As Usual” and ‘State of Florida Policy” scenarios. Two master scenarios: “Electrification” and “Energy efficiency and Lifestyle” were developed through combination of various mitigation scenarios: technological changes and energy efficiency and conservation. The results show a net reduction of the energy demand and GHG emissions by adopting these two energy scenarios compared to the business as usual.

Keywords: Integrated modeling, energy planning, climate change mitigation assessment, greenhouse gas emissions, renewable energy, energy efficiency.

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553 Synthesis, Characterization and Performance Study of Newly Developed Amine Polymeric Membrane (APM) for Carbon Dioxide (CO2) Removal

Authors: Rizwan Nasir, Hilmi Mukhtar, Zakaria Man, Dzeti Farhah Mohshim

Abstract:

Carbon dioxide has been well associated with greenhouse effect, and due to its corrosive nature it is an undesirable compound. A variety of physical-chemical processes are available for the removal of carbon dioxide. Previous attempts in this field have established alkanolamine group has the capability to remove carbon dioxide. So, this study combined the polymeric membrane and alkanolamine solutions to fabricate the amine polymeric membrane (APM) to remove carbon dioxide (CO2). This study entails the effect of three types of amines, monoethanolamine (MEA), diethanolamine (DEA), and methyldiethanolamine (MDEA). The effect of each alkanolamine group on the morphology and performance of polyether sulfone (PES) polymeric membranes was studied. Flat sheet membranes were fabricated by solvent evaporation method by adding polymer and different alkanolamine solutions in the N-Methyl-2-pyrrolidone (NMP) solvent. The final membranes were characterized by using Field Emission Electron Microscope (FESEM), Fourier Transform Infrared (FTIR), and Thermo-Gravimetric Analysis (TGA). The membrane separation performance was studied. The PES-DEA and PES-MDEA membrane has good ability to remove carbon dioxide. 

Keywords: Amine Polymeric membrane, Alkanolamine solution, CO2 Removal, Characterization.

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552 Formation of Vasoactive Amines in Dry Fermented Sausage Petrovská Klobása during Drying and Ripening in Traditional and Industrial Conditions

Authors: Tatjana A. Tasić, Predrag M. Ikonić, Ljiljana S. Petrović, Marija R. Jokanović, Vladimir M. Tomović, Branislav V. Šojić, Snežana B. Škaljac

Abstract:

Formation of histamine, tryptamine, phenylethylamine and tyramine (vasoactive amines) in dry fermented sausage Petrovská klobása during drying and ripening in traditional room (B1) and industrial ripening chamber (B3) were investigated. Dansyl chloride derivatized vasoactive amines were determined using HPLC-DAD on Eclipse XDB-C18 column.

Histamine, the most important amine from food safety point of view, was not detected in any analyzed sample. Unlike most of the other fermented sausages, where tyramine is reported as the most abundant amine, in Petrovská klobása tryptamine was the most abundant vasoactive amine in both groups of sausages even though concentrations of tryptamine and tyramine in B3 sausages at the end of ripening were nearly the same (39.8 versus 39.6mg/kg). Sum of vasoactive amines in samples varied from not detected ND (B3) to 176 mg/kg (B1), with concentration of 36.1 (B3) and 73.6 (B1) mg/kg at the end of drying and 96 (B3) and 176 (B1) mg/kg at the end of ripening period. Although the sum of vasoactive amines has increased from the end of drying (45. and 90. day) to the end of ripening period (120. day), during whole production period these values did not exceed 200 mg/kg proposed as possible indicator of hygienic conditions and GMP in the sausage production.

Keywords: Vasoactive amines, traditional dry fermented sausage Petrovská klobása.

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551 Characterization of the Near-Wake of an Ahmed Body Profile

Authors: Stéphanie Pellerin, Bérengére Podvin, Luc Pastur

Abstract:

In aerovehicles context, the flow around an Ahmed body profile is simulated using the velocity-vorticity formulation of the Navier-Stokes equations, associated to a penalization method for solids and Large Eddy Simulation for turbulence. The study focuses both on the ground influence on the flow and on the dissymetry of the wake, observed for a ground clearance greater than 10% of the body height H. Unsteady and mean flows are presented and analyzed. POD study completes the analysis and gives information on the most energetic structures of the flow.

Keywords: Ahmed body, bi-stability, LES, near wake.

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550 Solubility of CO2 in Aqueous Solutions of 2- Amino-2-Methyl-1-Propanol at High Pressure

Authors: Azmi Mohd Shariff, Ghulam Murshid, K.K. Lau, Mohammad Azmi Bustam, Faizan Ahamd

Abstract:

Carbon dioxide is one of the major green house gases. It is removed from different streams using amine absorption process. Sterically hindered amines are suggested as good CO2 absorbers. Solubility of carbon dioxide (CO2) was measured in aqueous solutions of 2-Amino-2-methyl-1-propanol (AMP) at temperatures 30 oC, 40 oC and 60 oC. The effect of pressure and temperature was studied over various concentrations of AMP. It has been found that pressure has positive effect on CO2 solubility where as solubility decreased with increasing temperature. Absorption performance of AMP increased with increasing pressure. Solubility of aqueous AMP was compared with mo-ethanolamine (MEA) and the absorption capacity of aqueous solutions of AMP was found to be better.

Keywords: Global warming, Carbon dioxide, Amine, Solubility

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549 The Impact of the Cell-Free Solution of Lactic Acid Bacteria on Cadaverine Production by Listeria monocytogenes and Staphylococcus aureus in Lysine-Decarboxylase Broth

Authors: Fatih Özogul, Nurten Toy, Yesim Özogul

Abstract:

The influences of cell-free solutions (CFSs) of lactic acid bacteria (LAB) on cadaverine and other biogenic amines production by Listeria monocytogenes and Staphylococcus aureus were investigated in lysine decarboxylase broth (LDB) using HPLC. Cell free solutions were prepared from Lactococcus lactis subsp. lactis, Leuconostoc mesenteroides subsp. cremoris, Pediococcus acidilactici and Streptococcus thermophiles. Two different concentrations that were 50% and 25% CFS and the control without CFSs were prepared. Significant variations on biogenic amine production were observed in the presence of L. monocytogenes and S. aureus (P < 0.05). The function of CFS on biogenic amine production by foodborne pathogens varied depending on strains and specific amine. Cadaverine formation by L. monocytogenes and S. aureus in control were 500.9 and 948.1 mg/L, respectively while the CFSs of LAB induced 4-fold lower cadaverine production by L. monocytogenes and 7-fold lower cadaverine production by S. aureus. The CFSs resulted in strong decreases in cadaverine and putrescine production by L. monocytogenes and S. aureus, although remarkable increases were observed for histamine, spermidine, spermine, serotonin, dopamine, tyramine and agmatine in the presence of LAB in lysine decarboxylase broth.

Keywords: Cell-free solution, lactic acid bacteria, cadaverine, food borne-pathogen.

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548 Environmental Friendly Polyurethane Coatings Based On Hyperbranched Resin

Authors: Ashraf M. Elsaid, Magd M. Badr, Mohamed S. Selim

Abstract:

Water borne polyurethane (PU) based on newly prepared hyperbranched poly (amine-ester) (HBPAE) was applied and evaluated as organic coating material. HBPAE was prepared through one-pot synthesis between trimethylol propane as a core and AB2 branched monomer which was obtained via Michal addition of methyl methacrylate (MMA) and diethanol amine (DEA). PU was prepared from HBPAE using different ratios of toluene diisocyanate (TDI) to form cured coating film. The prepared HBPAE was characterized using; GPC, FT-IR and 1H-NMR. The mechanical properties (impact, hardness, adhesion, and flexibility), thermal properties (DSC and TGA) and chemical resistance of the applied film were estimated. The results indicated 50% of TDI is the selected ratio. This formulation represents a promising candidate to be used as coating material.

Keywords: Curing, Hyperbranched polymer, Polyurethane, Urethane-acrylates, water borne Coatings.

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547 Simulation and Assessment of Carbon Dioxide Separation by Piperazine Blended Solutions Using E-NRTL and Peng-Robinson Models: A Study of Regeneration Heat Duty

Authors: Arash Esmaeili, Zhibang Liu, Yang Xiang, Jimmy Yun, Lei Shao

Abstract:

High pressure carbon dioxide (CO2) absorption from a specific off-gas in a conventional column has been evaluated for the environmental concerns by the Aspen HYSYS simulator using a wide range of single absorbents and piperazine (PZ) blended solutions to estimate the outlet CO2 concentration, CO2 loading, reboiler power supply and regeneration heat duty to choose the most efficient solution in terms of CO2 removal and required heat duty. The property package, which is compatible with all applied solutions for the simulation in this study, estimates the properties based on electrolyte non-random two-liquid (E-NRTL) model for electrolyte thermodynamics and Peng-Robinson equation of state for vapor phase and liquid hydrocarbon phase properties. The results of the simulation indicate that PZ in addition to the mixture of PZ and monoethanolamine (MEA) demand the highest regeneration heat duty compared with other studied single and blended amine solutions respectively. The blended amine solutions with the lowest PZ concentrations (5wt% and 10wt%) were considered and compared to reduce the cost of process, among which the blended solution of 10wt%PZ+35wt%MDEA (methyldiethanolamine) was found as the most appropriate solution in terms of CO2 content in the outlet gas, rich-CO2 loading and regeneration heat duty.

Keywords: Absorption, amine solutions, Aspen HYSYS, CO2 loading, piperazine, regeneration heat duty.

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546 Investigation of Inter Feeder Power Flow Regulator: Load Sharing Mode

Authors: Ahmed Hossam-Eldin, Ahmed Elserougi, Ahmed Massoud, Shehab Ahmed

Abstract:

The Inter feeder Power Flow Regulator (IFPFR) proposed in this paper consists of several voltage source inverters with common dc bus; each inverter is connected in series with one of different independent distribution feeders in the power system. This paper is concerned with how to transfer power between the feeders for load sharing purpose. The power controller of each inverter injects the power (for sending feeder) or absorbs the power (for receiving feeder) via injecting suitable voltage; this voltage injection is simulated by voltage drop across series virtual impedance, the impedance value is selected to achieve the concept of power exchange between the feeders without perturbing the load voltage magnitude of each feeder. In this paper a new control scheme for load sharing using IFPFR is proposed.

Keywords: IFPFR, Load sharing, Power transfer

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545 Measurement Fractional Order Sallen-Key Filters

Authors: Ahmed Soltan, Ahmed G. Radwan, Ahmed M. Soliman

Abstract:

This work aims to generalize the integer order Sallen-Key filters into the fractional-order domain. The analysis in the case of two different fractional-order elements introduced where the general transfer function becomes four terms which is unusual in the conventional case. In addition, the effect of the transfer function parameters on the filter poles and hence the stability is introduced and closed forms for the filter critical frequencies are driven. Finally, different examples for the fractional order Sallen-Key filter design are presented with circuit simulations using ADS where a great matching between the numerical and simulation results is obtained.

Keywords: Analog Filter, Low-Pass Filter, Fractance, Sallen-Key, Stability.

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544 Replacement of Commercial Anti-Corrosion Material with a More Effective and Cost Efficient Compound Based on Electrolytic System Simulation

Authors: Saeid Khajehmandali, Fattah Mollakarimi, Zohreh Seyf

Abstract:

There was a high rate of corrosion in Pyrolysis Gasoline Hydrogenation (PGH) unit of Arak Petrochemical Company (ARPC), and it caused some operational problem in this plant. A commercial chemical had been used as anti-corrosion in the depentanizer column overhead in order to control the corrosion rate. Injection of commercial corrosion inhibitor caused some operational problems such as fouling in some heat exchangers. It was proposed to replace this commercial material with another more effective trouble free, and well-known additive by R&D and operation specialists. At first, the system was simulated by commercial simulation software in electrolytic system to specify low pH points inside the plant. After a very comprehensive study of the situation and technical investigations ,ammonia / monoethanol amine solution was proposed as neutralizer or corrosion inhibitor to be injected in a suitable point of the plant. For this purpose, the depentanizer column and its accessories system was simulated again in case of this solution injection. According to the simulation results, injection of new anticorrosion substance has no any side effect on C5 cut product and operating conditions of the column. The corrosion rate will be cotrolled, if the pH remains at the range of 6.5 to 8 . Aactual plant test run was also carried out by injection of ammonia / monoethanol amine solution at the rate of 0.6 Kg/hr and the results of iron content of water samples and corrosion test coupons confirmed the simulation results. Now, ammonia / monoethanol amine solution is injected to a suitable pint inside the plant and corrosion rate has decreased significantly.

Keywords: Corrosion, Pyrolysis Gasoline, Simulation, Corrosion test copoun.

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543 A Multilanguage Source Code Retrieval System Using Structural-Semantic Fingerprints

Authors: Mohamed Amine Ouddan, Hassane Essafi

Abstract:

Source code retrieval is of immense importance in the software engineering field. The complex tasks of retrieving and extracting information from source code documents is vital in the development cycle of the large software systems. The two main subtasks which result from these activities are code duplication prevention and plagiarism detection. In this paper, we propose a Mohamed Amine Ouddan, and Hassane Essafi source code retrieval system based on two-level fingerprint representation, respectively the structural and the semantic information within a source code. A sequence alignment technique is applied on these fingerprints in order to quantify the similarity between source code portions. The specific purpose of the system is to detect plagiarism and duplicated code between programs written in different programming languages belonging to the same class, such as C, Cµ, Java and CSharp. These four languages are supported by the actual version of the system which is designed such that it may be easily adapted for any programming language.

Keywords: Source code retrieval, plagiarism detection, clonedetection, sequence alignment.

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542 Assessment of Carbon Dioxide Separation by Amine Solutions Using Electrolyte Non-Random Two-Liquid and Peng-Robinson Models: Carbon Dioxide Absorption Efficiency

Authors: Arash Esmaeili, Zhibang Liu, Yang Xiang, Jimmy Yun, Lei Shao

Abstract:

A high pressure carbon dioxide (CO2) absorption from a specific gas in a conventional column has been evaluated by the Aspen HYSYS simulator using a wide range of single absorbents and blended solutions to estimate the outlet CO2 concentration, absorption efficiency and CO2 loading to choose the most proper solution in terms of CO2 capture for environmental concerns. The property package (Acid Gas-Chemical Solvent) which is compatible with all applied solutions for the simulation in this study, estimates the properties based on an electrolyte non-random two-liquid (E-NRTL) model for electrolyte thermodynamics and Peng-Robinson equation of state for the vapor and liquid hydrocarbon phases. Among all the investigated single amines as well as blended solutions, piperazine (PZ) and the mixture of piperazine and monoethanolamine (MEA) have been found as the most effective absorbents respectively for CO2 absorption with high reactivity based on the simulated operational conditions.

Keywords: Absorption, amine solutions, Aspen HYSYS, carbon dioxide, simulation.

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541 The Clinical Use of Ahmed Valve Implant as an Aqueous Shunt for Control of Uveitic Glaucoma in Dogs

Authors: Khaled M. Ali, M. A. Abdel-Hamid, Ayman A. Mostafa

Abstract:

Objective: Safety and efficacy of Ahmed glaucoma valve implantation for the management of uveitis induced glaucoma evaluated on the five dogs with uncontrollable glaucoma. Materials and Methods: Ahmed Glaucoma Valve (AGV®; New World Medical, Rancho Cucamonga, CA, USA) is a flow restrictive, nonobstructive self-regulating valve system. Preoperative ocular evaluation included direct ophthalmoscopy and measurement of the intraocular pressure (IOP). The implant was examined and primed prior to implantation. The selected site of the valve implantation was the superior quadrant between the superior and lateral rectus muscles. A fornix-based incision was made through the conjunectiva and Tenon’s capsule. A pocket is formed by blunt dissection of Tenon’s capsule from the episclera. The body of the implant was inserted into the pocket with the leading edge of the device around 8-10 mm from the limbus. Results: No post-operative complications were detected in the operated eyes except a persistent corneal edema occupied the upper half of the cornea in one case. Hyphaema was very mild and seen only in two cases which resolved quickly two days after surgery. Endoscopical evaluation for the operated eyes revealed a normal ocular fundus with clearly visible optic papilla, tapetum and retinal blood vessels. No evidence of hemorrhage, infection, adhesions or retinal abnormalities was detected. Conclusion: Ahmed glaucoma valve is safe and effective implant for treatment of uveitic glaucoma in dogs.

Keywords: Ahmed valve, endoscopy, glaucoma, ocular fundus.

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540 A New Algorithm for Solving Isothermal Carbonization of Wood Particle

Authors: Ahmed Mahmoudi, Imen Mejri, Mohamed A. Abbassi, Ahmed Omri

Abstract:

A new algorithm based on the lattice Boltzmann method (LBM) is proposed as a potential solver for one-dimensional heat and mass transfer for isothermal carbonization of wood particles. To check the validity of this algorithm, the LBM results have been compared with the published data and a good agreement is obtained. Then, the model is used to study the effect of reactor temperature and particle size on the evolution of the local temperature and mass loss inside the wood particle.

Keywords: Lattice Boltzmann Method, pyrolysis, conduction, carbonization.

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539 Removal of Methylene Blue from Aqueous Solution by Using Gypsum as a Low Cost Adsorbent

Authors: Muhammad A.Rauf, I.Shehadeh, Amal Ahmed, Ahmed Al-Zamly

Abstract:

Removal of Methylene Blue (MB) from aqueous solution by adsorbing it on Gypsum was investigated by batch method. The studies were conducted at 25°C and included the effects of pH and initial concentration of Methylene Blue. The adsorption data was analyzed by using the Langmuir, Freundlich and Tempkin isotherm models. The maximum monolayer adsorption capacity was found to be 36 mg of the dye per gram of gypsum. The data were also analyzed in terms of their kinetic behavior and was found to obey the pseudo second order equation.

Keywords: Adsorption, Dye, Gypsum, Kinetics, Methylene Blue.

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538 Analysis of Conduction-Radiation Heat Transfer in a Planar Medium: Application of the Lattice Boltzmann Method

Authors: Ahmed Mahmoudi, Imen Mejri, Mohamed A. Abbassi, Ahmed Omri

Abstract:

In this paper, the 1-D conduction-radiation problem is solved by the lattice Boltzmann method. The effects of various parameters such as the scattering albedo, the conduction–radiation parameter and the wall emissivity are studied. In order to check on the accuracy of the numerical technique employed for the solution of the considered problem, the present numerical code was validated with the published study. The found results are in good agreement with those published

Keywords: Conduction, lattice Boltzmann method, planar medium, radiation.

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537 Modeling and Analysis of SVPWM Based Dynamic Voltage Restorer

Authors: Ahmed Helal, Sherif Zain Elabideen, Ahmed Lotfy

Abstract:

In this paper the modeling and analysis of Space Vector Pulse Width Modulation (SVPWM) based Dynamic Voltage Restorer (DVR) using PSCAD/EMTDC software will be presented in details. The simulation includes full modeling of the SVPWM technique used to control the DVR inverter. A test power system composed of three phase voltage source, sag generator, DVR and three phase resistive load is used to demonstrate restoration capability of the DVR. The simulation results of the presented DVR proved excellent voltage sag mitigation to protect sensitive loads.

Keywords: Dynamic voltage restorer, power quality, simulationand modeling, voltage sag.

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536 Lattice Boltzmann Simulation of the Carbonization of Wood Particle

Authors: Ahmed Mahmoudi, Imen Mejri, Mohamed A. Abbassi, Ahmed Omri

Abstract:

A numerical study based on the Lattice Boltzmann Method (LBM) is proposed to solve one, two and three dimensional heat and mass transfer for isothermal carbonization of thick wood particles. To check the validity of the proposed model, computational results have been compared with the published data and a good agreement is obtained. Then, the model is used to study the effect of reactor temperature and thermal boundary conditions, on the evolution of the local temperature and the mass distributions of the wood particle during carbonization

Keywords: Lattice Boltzmann Method, pyrolysis conduction, carbonization, Heat and mass transfer.

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535 Radiation Heat Transfer Effect in Solid Oxide Fuel Cell: Application of the Lattice Boltzmann Method

Authors: Imen Mejri, Ahmed Mahmoudi, Mohamed A. Abbassi, Ahmed Omri

Abstract:

The radiation effect within the solid anode, electrolyte, and cathode SOFC layers problem has been investigated in this paper. Energy equation is solved by the Lattice Boltzmann method (LBM). The Rosseland method is used to model the radiative transfer in the electrodes. The Schuster-Schwarzschild method is used to model the radiative transfer in the electrolyte. Without radiative effect, the found results are in good agreement with those published. The obtained results show that the radiative effect can be neglected.

Keywords: SOFC, lattice Boltzmann method, conduction, radiation.

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534 Performance Analysis of Selective Adaptive Multiple Access Interference Cancellation for Multicarrier DS-CDMA Systems

Authors: Maged Ahmed, Ahmed El-Mahdy

Abstract:

In this paper, Selective Adaptive Parallel Interference Cancellation (SA-PIC) technique is presented for Multicarrier Direct Sequence Code Division Multiple Access (MC DS-CDMA) scheme. The motivation of using SA-PIC is that it gives high performance and at the same time, reduces the computational complexity required to perform interference cancellation. An upper bound expression of the bit error rate (BER) for the SA-PIC under Rayleigh fading channel condition is derived. Moreover, the implementation complexities for SA-PIC and Adaptive Parallel Interference Cancellation (APIC) are discussed and compared. The performance of SA-PIC is investigated analytically and validated via computer simulations.

Keywords: Adaptive interference cancellation, communicationsystems, multicarrier signal processing, spread spectrum

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533 A Systematic Approach for Design a Low-Cost Mobility Assistive Device for Elderly People

Authors: Omar Salah, Ahmed A. Ramadan, Salvatore Sessa, Ahmed A. Abo-Ismail

Abstract:

Walking and sit to stand are activities carried out by all the people many times during the day, but physical disabilities due to age and diseases create needs of assistive devices to help elderly people during their daily life. This study aims to study the different types and mechanisms of the assistive devices. We will analyze the limitations and the challenges faced by the researchers in this field. We will introduce the Assistive Device developed at the Egypt-Japan University of Science and Technology, named E-JUST Assistive Device (EJAD). EJAD will be a low cost intelligent assistive device to help elders in walking and sit-to-stand activities.

Keywords: Active walker, Assistive robotics, Standing Assistance, Walking Assistance

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532 Effects of Asphalt Modification with Nanomaterials on Fresh and Stored Bitumen

Authors: Ahmed W. Oda, Ahmed El-Desouky, Hassan Mahdy, Osama M. Moussa

Abstract:

Nanomaterials have many applications in the field of asphalt paving. Two locally produced nanomaterials were used in the asphalt binder modification. The nanomaterials used are Nanosilica (NS), and Nanoclay (NC). The virgin asphalt binder was characterized by the conventional tests. The bitumen was modified by 3%, 5% and 7% of NS and NC. The penetration index (PI), and the retaining penetration (RP) was calculated based on the results of the penetration and the softening point tests. The results show that the RP becomes 95.35% at 5% NS modified bitumen and reaches 97.56% when bitumen is modified with 3% NC. The results show significant improvement in the bitumen stiffness when modified by the two types of nanomaterials, either fresh or aged (stored).

Keywords: Bitumen, modified bitumen, aged, stored, nanomaterials.

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531 Optimal Design of Substation Grounding Grid Based on Genetic Algorithm Technique

Authors: Ahmed Z. Gabr, Ahmed A. Helal, Hussein E. Said

Abstract:

With the incessant increase of power systems capacity and voltage grade, the safety of grounding grid becomes more and more prominent. In this paper, the designing substation grounding grid is presented by means of genetic algorithm (GA). This approach purposes to control the grounding cost of the power system with the aid of controlling grounding rod number and conductor lengths under the same safety limitations. The proposed technique is used for the design of the substation grounding grid in Khalda Petroleum Company “El-Qasr” power plant and the design was simulated by using CYMGRD software for results verification. The result of the design is highly complying with IEEE 80-2000 standard requirements.

Keywords: Genetic algorithm, optimum grounding grid design, power system analysis, power system protection, single layer model, substation.

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