Search results for: Ahmed Mohammed Ghaleb
2086 Material Fracture Dynamic of Vertical Axis Wind Turbine Blade
Authors: Samir Lecheb, Ahmed Chellil, Hamza Mechakra, Brahim Safi, Houcine Kebir
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In this paper we studied fracture and dynamic behavior of vertical axis wind turbine blade, the VAWT is a historical machine, it has many properties, structure, advantage, component to be able to produce the electricity. We modeled the blade design then imported to Abaqus software for analysis the modes shapes, frequencies, stress, strain, displacement and stress intensity factor SIF, after comparison we chose the idol material. Finally, the CTS test of glass epoxy reinforced polymer plates to obtain the material fracture toughness Kc.Keywords: blade, crack, frequency, material, SIF
Procedia PDF Downloads 5492085 Multimodal Employee Attendance Management System
Authors: Khaled Mohammed
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This paper presents novel face recognition and identification approaches for the real-time attendance management problem in large companies/factories and government institutions. The proposed uses the Minimum Ratio (MR) approach for employee identification. Capturing the authentic face variability from a sequence of video frames has been considered for the recognition of faces and resulted in system robustness against the variability of facial features. Experimental results indicated an improvement in the performance of the proposed system compared to the Previous approaches at a rate between 2% to 5%. In addition, it decreased the time two times if compared with the Previous techniques, such as Extreme Learning Machine (ELM) & Multi-Scale Structural Similarity index (MS-SSIM). Finally, it achieved an accuracy of 99%.Keywords: attendance management system, face detection and recognition, live face recognition, minimum ratio
Procedia PDF Downloads 1552084 An Assessment of the Factors Affecting Green Building Technology (GBT) Adoption
Authors: Nuruddeen Usman, Usman Mohammed Gidado
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A construction and post construction activity in buildings contributes to environmental degradation, because of the generation of solid waste during construction to the production of carbon dioxide by the occupants during utilization. These problems were caused as a result of lack of adopting green building technology during and after construction. However, this study aims at conceptualizing the factors that are affecting the adoption of green building technology with a view to suggest better ways for its successful adoption in the construction industry through developing a green building technology model. Thus, the research findings show that: Economic, social, cultural, and technological progresses are the factors affecting Green Building Technology Adoption. Therefore, identifying these factors and developing the model might help in the successful adoption of green building technology.Keywords: green building technology, construction, post construction, degradation
Procedia PDF Downloads 6612083 Towards the Design of Gripper Independent of Substrate Surface Structures
Authors: Annika Schmidt, Ausama Hadi Ahmed, Carlo Menon
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End effectors for robotic systems are becoming more and more advanced, resulting in a growing variety of gripping tasks. However, most grippers are application specific. This paper presents a gripper that interacts with an object’s surface rather than being dependent on a defined shape or size. For this purpose, ingressive and astrictive features are combined to achieve the desired gripping capabilities. The developed prototype is tested on a variety of surfaces with different hardness and roughness properties. The results show that the gripping mechanism works on all of the tested surfaces. The influence of the material properties on the amount of the supported load is also studied and the efficiency is discussed.Keywords: claw, dry adhesion, insects, material properties
Procedia PDF Downloads 3592082 A Nanoindentation Study of Thin Film Prepared by Physical Vapor Deposition
Authors: Dhiflaoui Hafedh, Khlifi Kaouther, Ben Cheikh Larbi Ahmed
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Monolayer and multilayer coatings of CrN and AlCrN deposited on 100Cr6 (AISI 52100) substrate by PVD magnetron sputtering system. The micro structures of the coatings were characterized using atomic force microscopy (AFM). The AFM analysis revealed the presence of domes and craters which are uniformly distributed over all surfaces of the various layers. Nano indentation measurement of CrN coating showed maximum hardness (H) and modulus (E) of 14 GPa and 240 GPa, respectively. The measured H and E values of AlCrN coatings were found to be 30 GPa and 382 GPa, respectively. The improved hardness in both the coatings was attributed mainly to a reduction in crystallite size and decrease in surface roughness. The incorporation of Al into the CrN coatings has improved both hardness and Young’s modulus.Keywords: CrN, AlCrN coatings, hardness, nanoindentation
Procedia PDF Downloads 5572081 Fractional-Order Modeling of GaN High Electron Mobility Transistors for Switching Applications
Authors: Anwar H. Jarndal, Ahmed S. Elwakil
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In this paper, a fraction-order model for pad parasitic effect of GaN HEMT on Si substrate is developed and validated. Open de-embedding structure is used to characterize and de-embed substrate loading parasitic effects. Unbiased device measurements are implemented to extract parasitic inductances and resistances. The model shows very good simulation for S-parameter measurements under different bias conditions. It has been found that this approach can improve the simulation of intrinsic part of the transistor, which is very important for small- and large-signal modeling process.Keywords: fractional-order modeling, GaNHEMT, si-substrate, open de-embedding structure
Procedia PDF Downloads 3562080 3D Printing Technology in Housing Projects Construction
Authors: Mohammed F. Haddad, Mohammad A. Albenayyan
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Realistically, 3-D printing as a technology has not yet reached the required maturity level to handle construction housing projects for citizens on a country scale. However, potentially, it has all of the required elements for addressing this issue. There are two main high-level elements of this technology that need to be capitalized on in order for the technology to reach its full potential, technical and logistical. This paper aims to cover how 3-D printing can be a viable technical solution for housing projects and describe the impact of 3-D printing technical features on the logistical aspects of completing a housing project. Additionally, a perspective about 3-D printing in Saudi Arabia will be presented in order to give the reader an idea of where the kingdom stands in the deployment of this technology. Finally, a glimpse will be given regarding the potential utilization of this technology for space applications.Keywords: large-scale 3-D printing, additive manufacturing, D- shape, contour crafting
Procedia PDF Downloads 1282079 Energy Saving Techniques for MIMO Decoders
Authors: Zhuofan Cheng, Qiongda Hu, Mohammed El-Hajjar, Basel Halak
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Multiple-input multiple-output (MIMO) systems can allow significantly higher data rates compared to single-antenna-aided systems. They are expected to be a prominent part of the 5G communication standard. However, these decoders suffer from high power consumption. This work presents a design technique in order to improve the energy efficiency of MIMO systems; this facilitates their use in the next generation of battery-operated communication devices such as mobile phones and tablets. The proposed optimization approach consists of the use of low complexity lattice reduction algorithm in combination with an adaptive VLSI implementation. The proposed design has been realized and verified in 65nm technology. The results show that the proposed design is significantly more energy-efficient than conventional K-best MIMO systems.Keywords: energy, lattice reduction, MIMO, VLSI
Procedia PDF Downloads 3282078 Mathematical Model That Using Scrambling and Message Integrity Methods in Audio Steganography
Authors: Mohammed Salem Atoum
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The success of audio steganography is to ensure imperceptibility of the embedded message in stego file and withstand any form of intentional or un-intentional degradation of message (robustness). Audio steganographic that utilized LSB of audio stream to embed message gain a lot of popularity over the years in meeting the perceptual transparency, robustness and capacity. This research proposes an XLSB technique in order to circumvent the weakness observed in LSB technique. Scrambling technique is introduce in two steps; partitioning the message into blocks followed by permutation each blocks in order to confuse the contents of the message. The message is embedded in the MP3 audio sample. After extracting the message, the permutation codebook is used to re-order it into its original form. Md5sum and SHA-256 are used to verify whether the message is altered or not during transmission. Experimental result shows that the XLSB performs better than LSB.Keywords: XLSB, scrambling, audio steganography, security
Procedia PDF Downloads 3632077 Electrochemical Studies of Some Schiff Bases on the Corrosion of Steel in H2SO4 Solution
Authors: Ahmed A. Farag, M. A. Hgazy
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The influence of three Schiff bases (SB-I, SB-II, and SB-III) on the corrosion of carbon steel in 0.5 M H2SO4 solution was studied by potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) techniques. The inhibition efficiency increases with the concentration of the Schiff bases and follow the trend: SB-III > SB-II > SB-I. Tafel polarization measurements revealed that the three tested inhibitors function as anodic inhibitors. The thermodynamic parameters Kads and ΔGºads are calculated and discussed. The Langmuir isotherm equation was found to provide an accurate description of the adsorption behaviour of the investigated Schiff bases. Depending on the results, the inhibitive mechanism was proposed.Keywords: Schiff bases, corrosion inhibitors, EIS, adsorption
Procedia PDF Downloads 5422076 Critical Success Factors for Successful Energy Management Implementation towards Sustainability in Malaysian Universities
Authors: A. Abdullah Saleh, A. H. Mohammed, M. N. Abdullah
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Universities are increasingly consuming energy to support various activities. A large population of staff and students in Malaysian universities has led to excessive energy consumption which directly gives an impact to the environment. The key question then ascended "How well is an energy management (EM) been practiced in universities without taking the Critical Success Factors (CSFs) into consideration to ensure the management of university achieves the goals in reducing energy consumption". Review of past literature is carried out to establish CSFs for EM best practices. Thus, this paper highlighted the CSFs which have to be focused on by management of university to successfully measure the EM implementation and its performance. At the end of this paper, a theoretical framework is developed for EM success factors towards a sustainable university.Keywords: critical success factors, energy management, sustainability, Malaysian universities
Procedia PDF Downloads 4742075 Fusion of MOLA-based DEMs and HiRISE Images for Large-Scale Mars Mapping
Authors: Ahmed F. Elaksher, Islam Omar
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In this project, we used MOLA-based DEMs to orthorectify HiRISE optical images. The MOLA data was interpolated using the kriging interpolation technique. Corresponding tie points were then digitized from both datasets. These points were employed in co-registering both datasets using GIS analysis tools. Different transformation models, including the affine and projective transformation models, were used with different sets and distributions of tie points. Additionally, we evaluated the use of the MOLA elevations in co-registering the MOLA and HiRISE datasets. The planimetric RMSEs achieved for each model are reported. Results suggested the use of 3D-2D transformation models.Keywords: photogrammetry, Mars, MOLA, HiRISE
Procedia PDF Downloads 772074 A Robotic Cube to Preschool Children for Acquiring the Mathematical and Colours Concepts
Authors: Ahmed Amin Mousa, Tamer M. Ismail, M. Abd El Salam
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This work presents a robot called Conceptual Robotic Cube, CR-Cube. The robot can be used as an educational tool for children from the age of three. It has a cube shape attached with a camera colours sensor. In addition, it contains four wheels to move smoothly. The researchers prepared a questionnaire to measure the efficiency of the robot. The design and the questionnaire was presented to 11 experts who agreed that the robot is appropriate for learning numbering and colours for preschool children.
Keywords: CR-Cube, robotic cube, conceptual robot, conceptual cube, colour concept, early childhood education
Procedia PDF Downloads 4092073 The Effect of Aluminum Oxide Nanoparticles on the Optical Properties of (PVP-PEG) Blend
Authors: Hussein Hakim, Zainab Al-Ramadhan, Ahmed Hashim
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Polymer nano composites of polyvinylpyrrolidone and poly-ethylene glycol with different concentrations of aluminum oxide (Al2O3) nano particles have been prepared by solution cast method. The optical characterizations have been done by analyzing the absorption (A) spectra in the 300–800 nm spectral region. It was found that the optical energy gap decreases with the increasing of Al2O3 nano particles content. The optical constants (refractive index, extinction coefficient, real and imaginary parts of the dielectric constant) are changing with increasing aluminum oxide nano particle concentrations.Keywords: nanocomposites, polyvinylpyrrolidone, optical constants, polymers, blend
Procedia PDF Downloads 4242072 A New Internal Architecture Based On Feature Selection for Holonic Manufacturing System
Authors: Jihan Abdulazeez Ahmed, Adnan Mohsin Abdulazeez Brifcani
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This paper suggests a new internal architecture of holon based on feature selection model using the combination of Bees Algorithm (BA) and Artificial Neural Network (ANN). BA is used to generate features while ANN is used as a classifier to evaluate the produced features. Proposed system is applied on the Wine data set, the statistical result proves that the proposed system is effective and has the ability to choose informative features with high accuracy.Keywords: artificial neural network, bees algorithm, feature selection, Holon
Procedia PDF Downloads 4572071 Endodontics Flare-Up
Authors: Khalid Mohammed Idrees
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Endodontic treatment aims to reverse the disease process and thereby eliminate the associated signs of symptoms. When the treatment itself appears to initiate the onset of pain and /or swelling (endodontic flare-up), the result can be distressing to both the patient and the operator. Patient might even consider postoperative symptoms as a bench mark against which the clinician’s skills are measured. Obviously the treatment with the lowest prevalence of postoperative pain is usually the treatment of choice as long as effectiveness and cost are not compromised. Knowledge of the cause and mechanism behind intra appointment flare-up is of utmost importance for the clinician to properly prevent or manage this undesirable condition. This review lecture will discuss the causative factors of flare-up with special attention to the microorganism role, various modalities of preventive measures would be discussed. Those measures are based on scientific evidence combined with the long clinical experience of the lecturer.Keywords: endodontic flare-up, causative factors, inflammatory mediators, preventive measures
Procedia PDF Downloads 1332070 Numerical Simulation of Fluid Structure Interaction Using Two-Way Method
Authors: Samira Laidaoui, Mohammed Djermane, Nazihe Terfaya
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The fluid-structure coupling is a natural phenomenon which reflects the effects of two continuums: fluid and structure of different types in the reciprocal action on each other, involving knowledge of elasticity and fluid mechanics. The solution for such problems is based on the relations of continuum mechanics and is mostly solved with numerical methods. It is a computational challenge to solve such problems because of the complex geometries, intricate physics of fluids, and complicated fluid-structure interactions. The way in which the interaction between fluid and solid is described gives the largest opportunity for reducing the computational effort. In this paper, a problem of fluid structure interaction is investigated with two-way coupling method. The formulation Arbitrary Lagrangian-Eulerian (ALE) was used, by considering a dynamic grid, where the solid is described by a Lagrangian formulation and the fluid by a Eulerian formulation. The simulation was made on the ANSYS software.Keywords: ALE, coupling, FEM, fluid-structure, interaction, one-way method, two-way method
Procedia PDF Downloads 6782069 Catalytic Deoxygenation of Propionic Acid in the Vapour Phase
Authors: Hossein Bayahia, Mohammed Saad Motlaq Al-Gahmdi
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The gas-phase deoxygenation of propionic acid was investigated in the presence of Co-Mo catalysts in N2 or H2 flow at 200-400 °C. In the presence of N2 the main product was 3-pentanone with other deoxygenates and some light gases: ethane and ethene. Using H2 flow, the catalyst was active for decarboxylation and decarbonylation of acid and the yields of ethane and ethene. The decarboxylation and decarbonylation reactions increased with increasing temperature. Cobalt-molybdenum supported on alumina showed better performance than bulk catalyst, especially at 400 °C in the presence of N2 for the ketonisation of propionic acid to form 3-pentanone as the main product. Bulk and supported catalysts were characterized by surface area porosity (BET), thermogravimetric analysis (TGA) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of pyridine adsorption.Keywords: deoxygenation, propionic acid, gas-phase, catalyst
Procedia PDF Downloads 2872068 Acupuncture and Topiramat in Treatment of Migraine
Authors: Lazgeen Mohammed
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The greatest advantage of acupuncture over western medicine is that it is safe . Unlike synthetic drugs, acupuncture has virtually no side effects, and the procedures for treating headaches are much less invasive. Migraine headaches are usually one-sided, pulsating or throbbing, and moderate or severe in intensity.. Some patients also experience auras, a neurological symptom that develops gradually over 5-20 minutes. The patient may see brief flashes or waves of light, or changes in their vision. Other common features of auras include vertigo, imbalance, confusion and numbness.Acupuncture had been used to treat 50 patients suffering from migraine ,topiramat (topamax) given to prevent the attacks, duration of treatment is 10 weeks , the patients were fallowed up for one year .Topiramat is called an anticonvulsant.Topiramat is also used to prevent migraine headaches in adults and teenagers who are at least 12 years old. This medicine will only prevent migraine headaches or reduce the number of attacks. It will not treat a headache that has already begun.Keywords: acpuncture, migraine, topiramat, headache
Procedia PDF Downloads 712067 Foreign News Coverage in Conservative and Liberal U.S. Newspapers: A Case Study of Saudi Arabia
Authors: Mohammed Huraysi
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This research will investigate the historical coverage of foreign issues in U.S. newspapers. The study will focus on three main areas, which are coverage of wars, foreign leaders, and human rights in foreign countries, and analyze them by applying the framing theory to news stories about Saudi Arabia, used as a case study, within two different newspapers over some time Wall Street Journal and The New York Times will be investigated and representative of two distinct newspaper orientations, which are conservative and liberal ideological orientations. By the end of this research study, comprehensive coverage of these topics in U.S. newspapers from past to present will be provided, leading to an ability to discover consistency or lack thereof, explain the present, and devise future expectations.Keywords: framing theory, US newspapers, historical research, Saudi Arabia
Procedia PDF Downloads 912066 The Environmental Impact of Sustainability Dispersion of Chlorine Releases in Coastal Zone of Alexandra: Spatial-Ecological Modeling
Authors: Mohammed El Raey, Moustafa Osman Mohammed
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The spatial-ecological modeling is relating sustainable dispersions with social development. Sustainability with spatial-ecological model gives attention to urban environments in the design review management to comply with Earth’s System. Naturally exchange patterns of ecosystems have consistent and periodic cycles to preserve energy flows and materials in Earth’s System. The probabilistic risk assessment (PRA) technique is utilized to assess the safety of industrial complex. The other analytical approach is the Failure-Safe Mode and Effect Analysis (FMEA) for critical components. The plant safety parameters are identified for engineering topology as employed in assessment safety of industrial ecology. In particular, the most severe accidental release of hazardous gaseous is postulated, analyzed and assessment in industrial region. The IAEA- safety assessment procedure is used to account the duration and rate of discharge of liquid chlorine. The ecological model of plume dispersion width and concentration of chlorine gas in the downwind direction is determined using Gaussian Plume Model in urban and ruler areas and presented with SURFER®. The prediction of accident consequences is traced in risk contour concentration lines. The local greenhouse effect is predicted with relevant conclusions. The spatial-ecological model is also predicted the distribution schemes from the perspective of pollutants that considered multiple factors of multi-criteria analysis. The data extends input–output analysis to evaluate the spillover effect, and conducted Monte Carlo simulations and sensitivity analysis. Their unique structure is balanced within “equilibrium patterns”, such as the biosphere and collective a composite index of many distributed feedback flows. These dynamic structures are related to have their physical and chemical properties and enable a gradual and prolonged incremental pattern. While this spatial model structure argues from ecology, resource savings, static load design, financial and other pragmatic reasons, the outcomes are not decisive in artistic/ architectural perspective. The hypothesis is an attempt to unify analytic and analogical spatial structure for development urban environments using optimization software and applied as an example of integrated industrial structure where the process is based on engineering topology as optimization approach of systems ecology.Keywords: spatial-ecological modeling, spatial structure orientation impact, composite structure, industrial ecology
Procedia PDF Downloads 802065 Smart Trust Management for Vehicular Networks
Authors: Amel Ltifi, Ahmed Zouinkhi, Med Salim Bouhlel
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Spontaneous networks such as VANET are in general deployed in an open and thus easily accessible environment. Therefore, they are vulnerable to attacks. Trust management is one of a set of security solutions dedicated to this type of networks. Moreover, the strong mobility of the nodes (in the case of VANET) makes the establishment of a trust management system complex. In this paper, we present a concept of ‘Active Vehicle’ which means an autonomous vehicle that is able to make decision about trustworthiness of alert messages transmitted about road accidents. The behavior of an “Active Vehicle” is modeled using Petri Nets.Keywords: active vehicle, cooperation, petri nets, trust management, VANET
Procedia PDF Downloads 4052064 River's Bed Level Changing Pattern Due to Sedimentation, Case Study: Gash River, Kassala, Sudan
Authors: Faisal Ali, Hasssan Saad Mohammed Hilmi, Mustafa Mohamed, Shamseddin Musa
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The Gash rivers an ephemeral river, it usually flows from July to September, it has a braided pattern with high sediment content, of 15200 ppm in suspension, and 360 kg/sec as bed load. The Gash river bed has an average slope of 1.3 m/Km. The objectives of this study were: assessing the Gash River bed level patterns; quantifying the annual variations in Gash bed level; and recommending a suitable method to reduce the sediment accumulation on the Gash River bed. The study covered temporally the period 1905-2013 using datasets included the Gash river flows, and the cross sections. The results showed that there is an increasing trend in the river bed of 5 cm3 per year. This is resulted in changing the behavior of the flood routing and consequently the flood hazard is tremendously increased in Kassala city.Keywords: bed level, cross section, gash river, sedimentation
Procedia PDF Downloads 5412063 Modeling and Simulation of the Tripod Gait of a Hexapod Robot
Authors: El Hansali Hasnaa, Bennani Mohammed
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Hexapod legged robot’s missions, particularly in irregular and dangerous areas, require high stability and high precision. In this paper, we consider the rectangular architecture body of legged robots with six legs distributed symmetrically along two sides, each leg contains three degrees of freedom for greater mobility. The aim of this work is planning tripod gait trajectory, based on the computing of the kinematic model to determine the joint variables in the lifting and the propelling phases. For this, appropriate coordinate frames are attached to the body and legs in order to obtain clear representation and efficient generation of the system equations. A simulation in MATLAB software platform is developed to confirm the kinematic model and various trajectories to the tripod gait adopted by the hexapod robot in its locomotion.Keywords: hexapod legged robot, inverse kinematic model, simulation in MATLAB, tripod gait
Procedia PDF Downloads 2772062 Cooperative Learning Mechanism in Intelligent Multi-Agent System
Authors: Ayman M. Mansour, Bilal Hawashin, Mohammed A. Mansour
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In this paper, we propose a cooperative learning mechanism in a multi-agent intelligent system. The basic idea is that intelligent agents are capable of collaborating with one another by sharing their knowledge. The agents will start collaboration by providing their knowledge rules to the other agents. This will allow the most important and insightful detection rules produced by the most experienced agent to bubble up for the benefit of the entire agent community. The updated rules will lead to improving the agents’ decision performance. To evaluate our approach, we designed a five–agent system and implemented it using JADE and FuzzyJess software packages. The agents will work with each other to make a decision about a suspicious medical case. This system provides quick response rate and the decision is faster than the manual methods. This will save patients life.Keywords: intelligent, multi-agent system, cooperative, fuzzy, learning
Procedia PDF Downloads 6842061 Experimental Testing of Solar Still with Movable Inclined Surface and Equipped with Wick
Authors: Ahmed N. Shmroukh
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This study examined a new solar still equipped with a movable inclined back, and this back is covered with a wick for seawater desalination. The tested backside inclination angles were 105, 125 and 160, respectively. The wick helped in increasing the seawater evaporation rate by increasing the evaporation surface area allowed for seawater in the still basin. The proposed modified solar still was compared with the conventional simple still. The results showed that the daily produced desalinated water of the modified solar still with angles 105, 125 and 160 increased by approximately 13.7%, 27.9%, and 39.2%, respectively, compared with the conventional solar still.Keywords: solar still, inclined still, porous materials, Wick
Procedia PDF Downloads 672060 Toxicity of the Chlorfenapyr: Growth Inhibition and Induction of Oxidative Stress on a Freshwater Protozoan, Paramecium Sp.
Authors: Houneïda Benbouzid, Houria Berrebbah, Mohammed-Réda Djebar
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The toxicological impacts of the increasing number of synthetic compounds present in the aquatic environment are assessed predominantly in laboratory studies where test organisms are exposed to a range of concentrations of single compounds. The bio-indicator Paramecium sp., characterized by a short life cycle, rapid multiplication and normal behavior that may be affected by the presence of pollutants. We therefore investigated the inhibitory effect of a newly synthesized acaricide: the chlorfenapyr tested at concentrations of 250, 300, and 350 µM on a pure culture of Paramecium sp. during 6 day. Paramecia treated with different concentrations of Chlorfenapyr illustrate strong inhibition of cell growth from the second day of treatment. Low levels of glutathione, increased glutathione S-transferase and the decrease in respiratory metabolism, recorded in the presence of different concentrations of Chlorfenapyr, involve the activation of detoxification system.Keywords: Paramecium sp., chlorfenapyr, oxidative enzymes, detoxification
Procedia PDF Downloads 3672059 Throughput of Point Coordination Function (PCF)
Authors: Faisel Eltuhami Alzaalik, Omar Imhemed Alramli, Ahmed Mohamed Elaieb
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The IEEE 802.11 defines two modes of MAC, distributed coordination function (DCF) and point coordination function (PCF) mode. The first sub-layer of the MAC is the distributed coordination function (DCF). A contention algorithm is used via DCF to provide access to all traffic. The point coordination function (PCF) is the second sub-layer used to provide contention-free service. PCF is upper DCF and it uses features of DCF to establish guarantee access of its users. Some papers and researches that have been published in this technology were reviewed in this paper, as well as talking briefly about the distributed coordination function (DCF) technology. The simulation of the PCF function have been applied by using a simulation program called network simulator (NS2) and have been found out the throughput of a transmitter system by using this function.Keywords: DCF, PCF, throughput, NS2
Procedia PDF Downloads 5772058 Advancements in Hydraulic Fracturing for Unconventional Resources
Authors: Salar Ahmed Ali
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Hydraulic fracturing has revolutionized the extraction of unconventional oil and gas resources, significantly increasing global energy reserves. This paper explores recent advancements in hydraulic fracturing technologies, focusing on the integration of real-time monitoring systems, environmentally friendly fracturing fluids, and nanotechnology applications. Case studies demonstrate how innovative approaches have enhanced resource recovery while minimizing environmental impact and operational costs. Additionally, the paper addresses challenges such as induced seismicity and regulatory constraints, proposing solutions to ensure sustainable development. These advancements promise to make hydraulic fracturing more efficient, sustainable, and adaptable to the evolving energy landscape.Keywords: oil, gas, fracture, hydraulic
Procedia PDF Downloads 82057 Expert and Novice Problem-Solvers Differences: A Discourse for Effective Teaching Delivery in Physics Classrooms
Authors: Abubakar Sa’adatu Mohammed
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This paper reports on a study of problem solving differences between expert and novice Problem solvers for effective physics teaching. Significant differences were found both at the conceptual level and at the level of critical thinking, creative thinking and reasoning. It is suggested for a successful solution of a problem, conceptual knowledge alone may not be sufficient. There is the need of the knowledge of how the conceptual knowledge should be applied (problem solving skills). It is hoped that this research might contribute to efforts of exploring ways for students to acquire a powerful conceptual toolkit based on experts like problem solvers approach for effective teaching delivery.Keywords: conceptual knowledge, procedural knowledge, critical thinking, creative thinking, reasoning ability
Procedia PDF Downloads 299