Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 243

Search results for: Hamdi Omar

243 Orbital Tuning of Marl-Limestone Alternations (Upper Tithonian to Upper Berriasian) in North-South Axis (Tunisia): Geochronology and Sequence Implications

Authors: Chokri Yaich, Hamdi Omar Omar, Hela Fakhfakh

Abstract:

This work reflects the integration of different techniques, such as field sampling and observations, magnetic susceptibility measurement, cyclostratigaraphy and sequence stratigraphy. The combination of these results allows us to reconstruct the environmental evolution of the Sidi Khalif Formation in the North-South Axis (NOSA), aged of Upper Tithonian, Berriasian and Lower Valanginian. Six sedimentary facies were identified and are primarily influenced by open marine sedimentation receiving increasing terrigenous influx. Spectral analysis, based on MS variation (for the outcropped section) and wireline logging gamma ray (GR) variation (for the sub-area section) show a pervasive dominance of 405-kyr eccentricity cycles with the expression of 100-kyr eccentricity, obliquity and precession. This study provides (for the first time) a precise duration of 2.4 myr for the outcropped Sidi Khalif Formation with a sedimentation rate of 5.4 cm/kyr and the sub-area section to 3.24 myr with a sedimentation rate of 7.64 cm/kyr. We outlined 27 5th-order depositional sequences, 8 Milankovitch depositional sequences and 2 major 3rd-order cycles for the outcropping section, controlled by the long eccentricity (405 kyr) cycles and the precession index cycles. This study has demonstrated the potential of MS and GR to be used as proxies to develop an astronomically calibrated time-scale for the Mesozoic era.

Keywords: magnetic susceptibility, Berriasian, orbital tuning, Sidi Khalif Formation

Procedia PDF Downloads 116
242 The Impact of Innovation Catalog of Products to Achieve the Fulfillment of Customers

Authors: Azzi Mohammed Amin

Abstract:

The study aimed to measure the impact of the product for its size marketing innovation (the development of existing products, innovation of new products) in achieving customer loyalty from the perspective of a sample of consumers brand (Omar Ben Omar) food in the state of Biskra, and also measure the degree of customer loyalty to the brand. To achieve the objectives of the study, designed a form and distributed to a random sample of 280 consumers of the brand, has been relying on SPSS to analyze the results, the study revealed several findings; There is a strong customer loyalty to Omar bin Omar products. The presence of the impact of product innovation (development of existing products, the innovation of new products) on customer loyalty, with a Pearson correlation coefficient of 0.74 is a strong relationship. The presence of a statistically significant effect for the development of existing products in customer loyalty. The presence of a statistically significant effect for the innovation of new products to customer loyalty.

Keywords: products, Product Innovation, Marketing Innovation, Customer Loyalty

Procedia PDF Downloads 361
241 Rock Slope Stabilization and Protection for Roads and Multi-Storey Structures in Jabal Omar, Saudi Arabia

Authors: Abdelazim Ibrahim, Ibrahim Abdel Gadir Malik, Dafalla Siddig Dafalla

Abstract:

Jabal Omar is located in the western side of Makkah city in Saudi Arabia. The proposed Jabal Omar Development project includes several multi-storey buildings, roads, bridges and below ground structures founded at various depths. In this study, geological mapping and site inspection which covered pre-selected areas were carried out within the easily accessed parts. Geological features; including rock types, structures, degree of weathering, and geotechnical hazards were observed and analyzed with specified software and also were documented in form of photographs. The presence of joints and fractures in the area made the rock blocks small and weak. The site is full of jointing; it was observed that, the northern side consists of 3 to 4 jointing systems with 2 random fractures associated with dykes. The southern part is affected by 2 to 3 jointing systems with minor fault and shear zones. From the field measurements and observations, it was concluded that, the Jabal Omar intruded by andesitic and basaltic dykes of different thickness and orientation. These dykes made the outcrop weak, highly deformed and made the rock masses sensitive to weathering.

Keywords: Protection, rock, Stabilization, slope, Makkah

Procedia PDF Downloads 423
240 Immediate and Long-Term Effect of the Sawdust Usage on Shear Strength of the Clayey Silt Soil

Authors: Dogan Cetin, Omar Hamdi Jasim

Abstract:

Using some additives is very common method to improve the soil properties such as shear strength, bearing capacity; and to reduce the settlement and lateral deformation. Soil reinforcement with natural materials is an attractive method to improve the soil properties because of their low cost. However, the studies conducted by using natural additive are very limited. This paper presents the results of an investigation on the immediate and long-term effects of the sawdust on the shear strength behavior of a clayey silt soil obtained in Arnavutkoy in Istanbul with sawdust. Firstly, compaction tests were conducted to be able to optimum moisture content for every percentage of sawdust. The samples were obtained from compacted soil at optimum moisture content. UU Triaxial Tests were conducted to evaluate the response of randomly distributed sawdust on the strength of low plasticity clayey silt soil. The specimens were tested with 1%, 2% and 3% content of sawdust. It was found that the undrained shear strength of clay soil with 1%, 2% and 3% sawdust were increased respectively 4.65%, 27.9% and 39.5% higher than the soil without additive. At 5%, shear strength of clay soil decreased by 3.8%. After 90 days cure period, the shear strength of the soil with 1%, 2%, 3% and %5 increased respectively 251%, 302%, 260% and 153%. It can be said that the effect of the sawdust usage has a remarkable effect on the undrained shear strength of the soil. Besides the increasing undrained shear strength, it was also found that the sawdust decreases the liquid limit, plastic limit and plasticity index by 5.5%, 2.9 and 10.9% respectively.

Keywords: Shear Strength, sawdust, compaction test, UU Triaxial Test

Procedia PDF Downloads 212
239 Chemical Vapor Deposition (CVD) of Molybdenum Disulphide (MoS2) Monolayers

Authors: Omar Omar, Yuan Jun, Hong Jinghua, Jin Chuanhong

Abstract:

In this work molybdenum dioxide (MoO2) and sulphur powders are used to grow MoS2 mono layers at elevated temperatures T≥800 °C. Centimetre scale continues thin films with grain size up to 410 µm have been grown using chemical vapour deposition. To our best knowledge, these domains are the largest that have been grown so far. Advantage of our approach is not only because of the high quality films with large domain size one can produce, but also the procedure is potentially less hazardous than other methods tried. The thin films have been characterized using transmission electron microscopy (TEM), atomic force microscopy (AFM) and Raman spectroscopy.

Keywords: molybdenum disulphide (MoS2), monolayers, chemical vapour deposition (CVD), growth and characterization

Procedia PDF Downloads 152
238 Treatment of Oil Recovery Water Using Direct and Indirect Electrochemical Oxidation

Authors: Tareg Omar Mansour, Khaled Omar Elhaji

Abstract:

Model solutions of pentanol in the salt water of various concentrations were subjected to electrochemical oxidation using a dimensionally stable anode (DSA) and a platinised titanium cathode. The removal of pentanol was analysed over time using gas chromatography (GC) and by monitoring the total organic carbon (TOC) concentration of the reaction mixture. It was found that the removal of pentanol occurred more efficiently at higher salinities and higher applied electrical current values. When using a salt concentration of 20,000 ppm and an applied current of 100 mA there was a decrease in concentration of pentanol of 15 %. When the salt concentration and applied current were increased to 58,000 ppm and 500 mA respectively, the decrease in concentration was improved to 64 %.

Keywords: Electrochemical Oxidation, dimensionally stable anode (DSA), total organic hydrocarbon (TOC), gas chromatography mass spectrometry (GCMS)

Procedia PDF Downloads 152
237 A Very Efficient Pseudo-Random Number Generator Based On Chaotic Maps and S-Box Tables

Authors: M. Hamdi, R. Rhouma, S. Belghith

Abstract:

Generating random numbers are mainly used to create secret keys or random sequences. It can be carried out by various techniques. In this paper we present a very simple and efficient pseudo-random number generator (PRNG) based on chaotic maps and S-Box tables. This technique adopted two main operations one to generate chaotic values using two logistic maps and the second to transform them into binary words using random S-Box tables. The simulation analysis indicates that our PRNG possessing excellent statistical and cryptographic properties.

Keywords: Cryptography, Random Numbers, Chaotic map, S-box, statistical tests

Procedia PDF Downloads 227
236 A Fault-Tolerant Full Adder in Double Pass CMOS Transistor

Authors: Abdelmonaem Ayachi, Belgacem Hamdi

Abstract:

This paper presents a fault-tolerant implementation for adder schemes using the dual duplication code. To prove the efficiency of the proposed method, the circuit is simulated in double pass transistor CMOS 32nm technology and some transient faults are voluntary injected in the Layout of the circuit. This fully differential implementation requires only 20 transistors which mean that the proposed design involves 28.57% saving in transistor count compared to standard CMOS technology.

Keywords: Digital Electronics, Integrated Circuits, full adder, double pass transistor technology, fault toleance, self-checking

Procedia PDF Downloads 230
235 Facies Sedimentology and Astronomic Calibration of the Reinech Member (Lutetian)

Authors: Jihede Haj Messaoud, Hamdi Omar, Hela Fakhfakh Ben Jemia, Chokri Yaich

Abstract:

The Upper Lutetian alternating marl–limestone succession of Reineche Member was deposited over a warm shallow carbonate platform that permits Nummulites proliferation. High-resolution studies of 30 meters thick Nummulites-bearing Reineche Member, cropping out in Central Tunisia (Jebel Siouf), have been undertaken, regarding pronounced cyclical sedimentary sequences, in order to investigate the periodicity of cycles and their related orbital-scale oceanic and climatic changes. The palaeoenvironmental and palaeoclimatic data are preserved in several proxies obtainable through high-resolution sampling and laboratories measurement and analysis as magnetic susceptibility (MS) and carbonates contents in conjunction with a wireline logging tools. The time series analysis of proxies permits to establish cyclicity orders present in the studied intervals which could be linked to the orbital cycles. MS records provide high-resolution proxies for relative sea level change in Late Lutetian strata. The spectral analysis of MS fluctuations confirmed the orbital forcing by the presence of the complete suite of orbital frequencies in the precession of 23 ka, the obliquity of 41 ka, and notably the two modes of eccentricity of 100 and 405 ka. Regarding the two periodic sedimentary cycles detected by wavelet analysis of proxy fluctuations which coincide with the long-term 405 ka eccentricity cycle, the Reineche Member spanned 0,8 Myr. Wireline logging tools as gamma ray and sonic were used as a proxies to decipher cyclicity and trends in sedimentation and contribute to identifying and correlate units. There are used to constraint the highest frequency cyclicity modulated by a long term wavelength cycling apparently controlled by clay content. Interpreted as a result of variations in carbonate productivity, it has been suggested that the marl-limestone couplets, represent the sedimentary response to the orbital forcing. The calculation of cycle durations through Reineche Member, is used as a geochronometer and permit the astronomical calibration of the geologic time scale. Furthermore, MS coupled with carbonate contents, and fossil occurrences provide strong evidence for combined detrital inputs and marine surface carbonate productivity cycles. These two synchronous processes were driven by the precession index and ‘fingerprinted’ in the basic marl–limestone couplets, modulated by orbital eccentricity.

Keywords: Spectral Analysis, Cyclostratigraphy, magnetic susceptibility, orbital forcing, Lutetian

Procedia PDF Downloads 179
234 Opto-Mechanical Characterization of Aspheric Lenses from the Hybrid Method

Authors: Aliouane Toufik, Hamdi Amine, Bouzid Djamel

Abstract:

Aspheric optical components are an alternative to the use of conventional lenses in the implementation of imaging systems for the visible range. Spherical lenses are capable of producing aberrations. Therefore, they are not able to focus all the light into a single point. Instead, aspherical lenses correct aberrations and provide better resolution even with compact lenses incorporating a small number of lenses. Metrology of these components is very difficult especially when the resolution requirements increase and insufficient or complexity of conventional tools requires the development of specific approaches to characterization. This work is part of the problem existed because the objectives are the study and comparison of different methods used to measure surface rays hybrid aspherical lenses.

Keywords: roughness, radius of curvature, manufacture of lenses, aspherical surface, precision molding

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233 Platelet Indices among the Cases of Vivax Malaria

Authors: Mirza Sultan Ahmad, Mubashra Ahmad, Ramlah Mehmood, Nazia Mahboob, Waqar Nasir

Abstract:

Objective: To ascertain the prevalence of thrombocytopenia and study changes in MPV and PDW among cases of vivax malaria. Design: Descriptive analytic study. Place and duration of study: Department of pediatrics, Fazle Omar Hospital, from January to December 2012. Methodology: All patients from birth to 16 years age, who presented in Fazle- Omar hospital, Rabwah from January to December 2012 were included in this study. Hundred patients with other febrile illnesses were taken as control. Full blood counts were checked by Madonic CA 620 analyzer. Name, age, sex, weight, platelet counts. MPV, PDW, any evidence of bleeding, outcome of cases included in this study and taken as control were recorded on data sheets. Results: One hundred and forty-two patients were included in this study. There was no incidence of death or active bleeding. Median platelet count was 109000/mm3. Thrombocytopenia was present in 108 (76.1%) patients. Severe thrombocytopenia was present in 10(7%) patients. Minimum count was 27000/mm3 and maximum was 341000/mm3. Platelet counts of control group was significantly more as compared with study group.(p<.001) Median MPV was 8.70. Minimum value was 6.40 and maximum was 11.90. MPV of study group was significantly more than control group.(p<.001) Median PDW was 11.30. Minimum value was 8.5 and maximum was 16.70. There was no difference between PDW of study and control groups (p=0.246). Conclusions: Thrombocytopenia is a common complication among pediatric cases of vivax malaria. MPV of cases of vivax malaria is higher than control group.

Keywords: platelet, thrombocytopenia, malaria vivax, mean platelet volume

Procedia PDF Downloads 186
232 Thermodynamic Analysis of Zeotropic Mixture Used in Low Temperature Solar Rankine Cycle with Ejector for Power Generation

Authors: Basma Hamdi, Lakdar Kairouani, Ezzedine Nahdi

Abstract:

The objective of this work is to present a thermodynamic analysis of low temperature solar Rankine cycle with ejector for power generation using zeotropic mixtures. Based on theoretical calculation, effects of zeotropic mixtures compositions on the performance of solar Rankine cycle with ejector are discussed and compared with corresponding pure fluids. Variations of net power output, thermal efficiency were calculating with changing evaporation temperature. The ejector coefficient had analyzed as independent variable. The result show that (R245fa/R152a) has a higher thermal efficiency than using pure fluids.

Keywords: Thermodynamic Analysis, ejector, zeotropic mixture, low-temperature solar rankine cycle

Procedia PDF Downloads 119
231 Highly Transparent, Hydrophobic and Self-Cleaning ZnO-Durazane Based Hybrid Organic-Inorganic Coatings

Authors: Abderrahmane Hamdi, Julie Chalon, Benoit Dodin, Philippe Champagne

Abstract:

In this report, we present a simple route to realize robust, hydrophobic, and highly transparent coatings using organic polysilazane (durazane) and zinc oxide nanoparticles (ZnO). These coatings were deposited by spraying the mixture solution on glass slides. Thus, the properties of the films were characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), UV–vis-NIR spectrophotometer, and water contact angle method. This sprayable polymer mixed with ZnO nanoparticles shows high transparency for visible light > 90%, a hydrophobic character (CA > 90°), and good mechanical and chemical stability. The coating also demonstrates excellent self-cleaning properties, which makes it a promising candidate for commercial use.

Keywords:

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230 Isolation and Characterization of Salt-Tolerance of Rhizobia under the Effects of Salinity

Authors: Sarra Sobti, Baelhadj Hamdi-Aïssa

Abstract:

The bacteria of the soil, usually called rhizobium, have a considerable importance in agriculture because of their capacity to fix the atmospheric nitrogen in symbiosis with the plants of the family of legumes. The present work was to study the effect of the salinity on growth and nodulation of alfalfa-rhizobia symbiosis at different agricultural experimental sites in Ouargla. The experiment was conducted in 3 steps. The first one was the isolation and characterization of the Rhizobia; next, the evolution of the isolates tolerance to salinity at three levels of NaCl (6, 8,12 and 16 g/L); and the last step was the evolution of the tolerance on symbiotic characteristics. The results showed that the phenotypic characterizations behave practically as Rhizobia spp, and the effects of salinity affect the symbiotic process. The tolerance to high levels of salinity and the survival and persistence in severe and harsh desert conditions make these rhizobia highly valuable inoculums to improve productivity of the leguminous plants cultivated under extreme environments.

Keywords: Tolerance, Soil, Symbiosis, Salinity, rhizobia, nodulation, Medicago sativa L

Procedia PDF Downloads 142
229 Comparison of DPC and FOC Vector Control Strategies on Reducing Harmonics Caused by Nonlinear Load in the DFIG Wind Turbine

Authors: Hamid Havasi, Mohamad Reza Gholami Dehbalaei, Hamed Khorami, Shahram Karimi, Hamdi Abdi

Abstract:

Doubly-fed induction generator (DFIG) equipped with a power converter is an efficient tool for converting mechanical energy of a variable speed system to a fixed-frequency electrical grid. Since electrical energy sources faces with production problems such as harmonics caused by nonlinear loads, so in this paper, compensation performance of DPC and FOC method on harmonics reduction of a DFIG wind turbine connected to a nonlinear load in MATLAB Simulink model has been simulated and effect of each method on nonlinear load harmonic elimination has been compared. Results of the two mentioned control methods shows the advantage of the FOC method on DPC method for harmonic compensation. Also, the fifth and seventh harmonic components of the network and THD greatly reduced.

Keywords: Energy Conversion, THD, DFIG machine, nonlinear load, DPC, FOC

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228 End-to-End Performance of MPPM in Multihop MIMO-FSO System Over Dependent GG Atmospheric Turbulence Channels

Authors: Noureddine Hamdi, Hechmi Saidi

Abstract:

The performance of decode and forward (DF) multihop free space optical (FSO) scheme deploying multiple input multiple output (MIMO) configuration under gamma-gamma (GG) statistical distribution, that adopts M-ary pulse position modulation (MPPM) coding, is investigated. We have extracted exact and estimated values of symbol-error rates (SERs) respectively. The probability density function (PDF)’s closed-form formula is expressed for our designed system. Thanks to the use of DF multihop MIMO FSO configuration and MPPM signaling, atmospheric turbulence is combatted; hence the transmitted signal quality is improved.

Keywords: radio frequency, decode and forward, free space optical, gamma gamma channel, M-ary pulse position modulation, symbol error rate, multiple-input multiple-output

Procedia PDF Downloads 131
227 Preparation of Geopolymer Cements from Tunisian Illito-Kaolinitic Clay Mineral

Authors: N. Hamdi, E. Srasra

Abstract:

In this work geopolymer cement are synthesized from Tunisian (illito-kaolinitic) clay. This product can be used as binding material in place of cement Portland. The clay fractions used were characterized with physico-chemical and thermal analyses. The clays materials react with alkaline solution (10, 14 and 18 mol(NaOH)/L) in order to produce geopolymer cements whose pastes were characterized by determining their water adsorption and compressive strength. The compressive strength of the hardened geopolymer cement paste samples aged 28 days attained its highest value (32.3MPa) around 950°C for NaOH concentration of 14M. The water adsorption value of the prepared samples decreased with increasing the calcination temperature of clay fractions. It can be concluded that the most suitable temperature for the calcination of illitio-kaolinitic clays in view of producing geopolymer cements is around 950°C.

Keywords: Mineral, Geopolymer Cement, compressive strength, illitio-kaolinitic clay

Procedia PDF Downloads 147
226 Improvement on a CNC Gantry Machine Structure Design for Higher Machining Speed Capability

Authors: M. Hamdi, Ahmed A. D. Sarhan, S. R. Besharaty, Javad Akbaria

Abstract:

The capability of CNC gantry milling machines in manufacturing long components has caused the expanded use of such machines. On the other hand, the machines’ gantry rigidity can reduce under severe loads or vibration during operation. Indeed, the quality of machining is dependent on the machine’s dynamic behavior throughout the operating process. For this reason, this type of machines has always been used prudently and are non efficient. Therefore, they can usually be employed for rough machining and may not produce adequate surface finishing. In this paper, a CNC gantry milling machine with the potential to produce good surface finish has been designed and analyzed. The lowest natural frequency of this machine is 202 Hz at all motion amplitudes with a full range of suitable frequency responses. Meanwhile, the maximum deformation under dead loads for the gantry machine is 0.565µm, indicating that this machine tool is capable of producing higher product quality.

Keywords: Frequency Response, finite element, gantry machine, gantry design, static and dynamic analysis

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225 Toxic Activity of Biopesticide Metarhizium anisopliae var acridium ‘Green Muscle’ on the Cuticle of the Desert Locust Schistocerca gegaria (Forskål, 1775)

Authors: F. Acheuk, F. Haddadj, S. Hamdi, S. Zenia, A. Smai, H. Saadi, B. Doumandji-Mitiche

Abstract:

Locust is causing significant losses in agricultural production in the countries concerned by the invasion. Up to the present control strategy has consisted only of the spreaders chemicals; they have proven harmful to the environment and taking a conscience prompted researchers and institutions to lean towards the biological control based mostly by using microorganism. It is in that sense is we've made our contribution by the use of a biopesticide which is entomopathogenic fungus Metarhizium anisopliae var acridium ‘Green Muscle’ on part of the cuticle the larval of fifth instar locust Schistocerca gregaria. Preliminary test on the study of the pathogenicity of the bio-control agent, was conducted in the laboratory on L5 S. gregaria, on which we inoculated treatment by direct spraying of the cuticle, 5 days after treatment individuals are sacrificed. Microscopic observation revealed alterations in the architecture of the cuticle which leads to disorganization of cell layers.

Keywords: effect, cuticle, biopesticide, desert locust

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224 Control and Automation of Sensors in Metering System of Fluid

Authors: Abdelkader Harrouz, Omar Harrouz, Ali Benatiallah

Abstract:

This paper is to present the essential definitions, roles and characteristics of automation of metering system. We discuss measurement, data acquisition and metrological control of a signal sensor from dynamic metering system. After that, we present control of instruments of metering system of fluid with more detailed discussions to the reference standards.

Keywords: Communication, Sensor, Computer, metering

Procedia PDF Downloads 379
223 Energy Calculation for Excited Lithium Atom in Position Space

Authors: Khalil H. Al-Bayati, Khalid Omar Al-Baiti

Abstract:

The energy expectation value for Li-like ions systems (Li, Be+ and Be2+) hasbeen calculated and examined within the ground state (1s2sα)^2 S and the excited state (1s3sα)^2 S in position space. The partitioning technique of Hartree-Fock (H-F) has been used for existing wavefnctions.

Keywords: energy expectation value, atomic systems, ground and excited states, Hartree-Fock approximation

Procedia PDF Downloads 441
222 Performance Analysis of a Hybrid DF-AF Hybrid RF/FSO System under Gamma Gamma Atmospheric Turbulence Channel Using MPPM Modulation

Authors: Noureddine Hamdi, Hechmi Saidi

Abstract:

The performance of hybrid amplify and forward - decode and forward (AF-DF) hybrid radio frequency/free space optical (RF/FSO) communication system, that adopts M-ary pulse position modulation (MPPM) techniques, is analyzed. Both exact and approximate symbol-error rates (SERs) are derived. The random variations of the received optical irradiance, produced by the atmospheric turbulence, is modeled by the gamma-gamma (GG) statistical distribution. A closed-form expression for the probability density function (PDF) is derived for the whole above system is obtained. Thanks to the use of hybrid AF-DF hybrid RF/FSO configuration and MPPM, the effects of atmospheric turbulence is mitigated; hence the capacity of combating atmospheric turbulence and the transmissitted signal quality are improved.

Keywords: radio frequency, decode and forward, free space optical, gamma gamma channel, error pointing, M-ary pulse position modulation, symbol error rate

Procedia PDF Downloads 125
221 Performance Analysis of M-Ary Pulse Position Modulation in Multihop Multiple Input Multiple Output-Free Space Optical System over Uncorrelated Gamma-Gamma Atmospheric Turbulence Channels

Authors: Noureddine Hamdi, Hechmi Saidi

Abstract:

The performance of Decode and Forward (DF) multihop Free Space Optical ( FSO) scheme deploying Multiple Input Multiple Output (MIMO) configuration under Gamma-Gamma (GG) statistical distribution, that adopts M-ary Pulse Position Modulation (MPPM) coding, is investigated. We have extracted exact and estimated values of Symbol-Error Rates (SERs) respectively. A closed form formula related to the Probability Density Function (PDF) is expressed for our designed system. Thanks to the use of DF multihop MIMO FSO configuration and MPPM signaling, atmospheric turbulence is combatted; hence the transmitted signal quality is improved.

Keywords: decode and forward, multihop, free space optical, M-ary pulse position modulation, symbol error rate, multiple input multiple output, gamma-gamma channel

Procedia PDF Downloads 49
220 Dual-Rail Logic Unit in Double Pass Transistor Logic

Authors: Hamdi Belgacem, Fradi Aymen

Abstract:

In this paper we present a low power, low cost differential logic unit (LU). The proposed LU receives dual-rail inputs and generates dual-rail outputs. The proposed circuit can be used in Arithmetic and Logic Units (ALU) of processor. It can be also dedicated for self-checking applications based on dual duplication code. Four logic functions as well as their inverses are implemented within a single Logic Unit. The hardware overhead for the implementation of the proposed LU is lower than the hardware overhead required for standard LU implemented with standard CMOS logic style. This new implementation is attractive as fewer transistors are required to implement important logic functions. The proposed differential logic unit can perform 8 Boolean logical operations by using only 16 transistors. Spice simulations using a 32 nm technology was utilized to evaluate the performance of the proposed circuit and to prove its acceptable electrical behaviour.

Keywords: differential logic unit, double pass transistor logic, low power CMOS design, low cost CMOS design

Procedia PDF Downloads 344
219 Synthesis and Characterization of Fluorine-Free, Hydrophobic and Highly Transparent Coatings

Authors: Philippe Champagne, Abderrahmane Hamdi, Julie Chalon, Benoit Dodin

Abstract:

This research work concerns the synthesis of hydrophobic and self-cleaning coatings as an alternative to fluorine-based coatings used on glass. The developed, highly transparent coatings are produced by a chemical route (sol-gel method) using two silica-based precursors, hexamethyldisilazane and tetraethoxysilane (HMDS/TEOS). The addition of zinc oxide nanoparticles (ZnO NPs) within the gel provides a photocatalytic property to the final coating. The prepared gels were deposited on glass slides using different methods. The properties of the coatings were characterized by optical microscopy, scanning electron microscopy, UV-VIS-NIR spectrophotometer, and water contact angle method. The results show that the obtained coatings are homogeneous and have a hydrophobic character. In particular, after thermal treatment, the HMDS/[email protected] charged gel deposited on glass constitutes a coating capable of degrading methylene blue (MB) under UV irradiation. Optical transmission reaches more than 90% in most of the visible light spectrum. Synthetized coatings have also demonstrated their mechanical durability and self-cleaning ability.

Keywords: Durability, Coating, sol-gel, hydrophobicity, self-cleaning, transparence

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218 Oil Recovery Study by Low Temperature Carbon Dioxide Injection in High-Pressure High-Temperature Micromodels

Authors: Zakaria Hamdi, Mariyamni Awang

Abstract:

For the past decades, CO2 flooding has been used as a successful method for enhanced oil recovery (EOR). However, high mobility ratio and fingering effect are considered as important drawbacka of this process. Low temperature injection of CO2 into high temperature reservoirs may improve the oil recovery, but simulating multiphase flow in the non-isothermal medium is difficult, and commercial simulators are very unstable in these conditions. Furthermore, to best of authors’ knowledge, no experimental work was done to verify the results of the simulations and to understand the pore-scale process. In this paper, we present results of investigations on injection of low temperature CO2 into a high-pressure high-temperature micromodel with injection temperature range from 34 to 75 °F. Effect of temperature and saturation changes of different fluids are measured in each case. The results prove the proposed method. The injection of CO2 at low temperatures increased the oil recovery in high temperature reservoirs significantly. Also, CO2 rich phases available in the high temperature system can affect the oil recovery through the better sweep of the oil which is initially caused by penetration of LCO2 inside the system. Furthermore, no unfavorable effect was detected using this method. Low temperature CO2 is proposed to be used as early as secondary recovery.

Keywords: Enhanced Oil Recovery, CO2 flooding, micromodel studies, miscible flooding

Procedia PDF Downloads 197
217 Design and Study of a Hybrid Micro-CSP/Biomass Boiler System for Water and Space Heating in Traditional Hammam

Authors: Said Lamghari, Abdelkader Outzourhit, Hassan Hamdi, Mohamed Krarouch, Fatima Ait Nouh, Mickael Benhaim, Mehdi Khaldoun

Abstract:

Traditional Hammams are big consumers of water and wood-energy. Any approach to reduce this consumption will contribute to the preservation of these two resources that are more and more stressed in Morocco. In the InnoTherm/InnoBiomass 2014 project HYBRIDBATH, funded by the Research Institute for Solar Energy and New Energy (IRESEN), we will use a hybrid system consisting of a micro-CSP system and a biomass boiler for water and space heating of a Hammam. This will overcome the problem of intermittency of solar energy, and will ensure continuous supply of hot water and heat. We propose to use local agricultural residues (olive pomace, shells of walnuts, almonds, Argan ...). Underfloor heating using either copper or PEX tubing will perform the space heating. This work focuses on the description of the system and the activities carried out so far: The installation of the system, the principle operation of the system and some preliminary test results.

Keywords: Hybrid systems, Solar energy, solar fraction, hot water, biomass boiler, micro-CSP, parabolic sensor, traditional hammam, underfloor heating

Procedia PDF Downloads 177
216 Long Short-Term Memory Based Model for Modeling Nicotine Consumption Using an Electronic Cigarette and Internet of Things Devices

Authors: Hamdi Amroun, Yacine Benziani, Mehdi Ammi

Abstract:

In this paper, we want to determine whether the accurate prediction of nicotine concentration can be obtained by using a network of smart objects and an e-cigarette. The approach consists of, first, the recognition of factors influencing smoking cessation such as physical activity recognition and participant’s behaviors (using both smartphone and smartwatch), then the prediction of the configuration of the e-cigarette (in terms of nicotine concentration, power, and resistance of e-cigarette). The study uses a network of commonly connected objects; a smartwatch, a smartphone, and an e-cigarette transported by the participants during an uncontrolled experiment. The data obtained from sensors carried in the three devices were trained by a Long short-term memory algorithm (LSTM). Results show that our LSTM-based model allows predicting the configuration of the e-cigarette in terms of nicotine concentration, power, and resistance with a root mean square error percentage of 12.9%, 9.15%, and 11.84%, respectively. This study can help to better control consumption of nicotine and offer an intelligent configuration of the e-cigarette to users.

Keywords: Automatic classification, IoT, Activity Recognition, unconstrained environment

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215 Improving Productivity in a Glass Production Line through Applying Principles of Total Productive Maintenance (TPM)

Authors: Omar Bataineh

Abstract:

Total productive maintenance (TPM) is a principle-based method that aims to get a high-level production with no breakdowns, no slow running and no defects. Key principles of TPM were applied in this work to improve the performance of the glass production line at United Beverage Company in Kuwait, which is producing bottles of soft drinks. Principles such as 5S as a foundation for TPM implementation, developing a program for equipment management, Cause and Effect Analysis (CEA), quality improvement, training and education of employees were employed. After the completion of TPM implementation, it was possible to increase the Overall Equipment Effectiveness (OEE) from 23% to 40%.

Keywords: FMEA, TPM, OEE, CEA

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214 α-Amylase Inhibitory Activity of Some Tunisian Aromatic and Medicinal Plants

Authors: Hamdi Belfeki, Belgacem Chandoul, Mnasser Hassouna, Mondher Mejri

Abstract:

Aqueous and ethanolic extracts of eight Tunisian aromatic and medicinal plants (TAMP) were characterized by studying their composition in polyphenols and also their antiradical and antioxidant capacities. In absence and in the presence of the various extracts, α-amylase from Bacillus subtlis activity, was measured in order to detect a potential inhibition. The total contents of polyphenols and flavonoid vary in function of TAMP and the mobile phase used for the extraction (distilled water or ethanol). The ethanolic extracts showed the most significant antiradical and antioxidant activities. Only the extracts from Coriandrum sativum showed a significant inhibiting effect on the α-amylase activity. This inhibiting capacity could be correlated with the chemical profile of the two extracts, due to the fact that they have the greatest amount of total flavonoid. The ethanolic extract has the most important antioxidant and anti-radicalizing activities among the sixteen extracts studied. The inhibition kinetics of the two coriander extracts were evaluated by pre-incubation method, using Lineweaver-Burk’s equation, obtained by linearization of Michaeilis-Menten’s expression. The results showed that both extracts exercised a competitive inhibition mechanism.

Keywords: antioxidant activity, inhibition, α-amylase, aromatic and medicinal plants

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