Search results for: Ahmed Mohammed Ghaleb
1936 Crushing Behaviour of Thin Tubes with Various Corrugated Sections Using Finite Element Modelling
Authors: Shagil Akhtar, Syed Muneeb Iqbal, Mohammed R. Rahim
Abstract:
Common steel tubes with similar confines were used in simulation of tubes with distinctive type of corrugated sections. These corrugated cross-sections were arc-tangent, triangular, trapezoidal and square corrugated sections. The outcome of fluctuating structures of tube cross-section shape on the deformation feedback, collapse form and energy absorption characteristics of tubes under quasi-static axial compression have been prepared numerically. The finite element package of ANSYS Workbench was applied in the current analysis. The axial load-displacement products accompanied by the fold formation of disparate tubes were inspected and compared. Deviation of the initial peak load and the mean crushing force of the tubes with distinctive cross-sections were conscientiously examined.Keywords: absorbed energy, axial loading, corrugated tubes, finite element, initial peak load, mean crushing force
Procedia PDF Downloads 3881935 Achieving Sustainable Rapid Construction Using Lean Principles
Authors: Muhamad Azani Yahya, Vikneswaran Munikanan, Mohammed Alias Yusof
Abstract:
There is the need to take the holistic approach in achieving sustainable construction for a contemporary practice. Sustainable construction is the practice that involved method of human preservation of the environment, whether economically or socially through responsibility, management of resources and maintenance utilizing support. This paper shows the correlation of achieving rapid construction with sustainable concepts using lean principles. Lean principles being used widely in the manufacturing industry, but this research will demonstrate the principles into building construction. Lean principle offers the benefits of stabilizing work flow and elimination of unnecessary work. Therefore, this principle contributes to time and waste reduction. The correlation shows that pulling factor provides the improvement of progress curve and stabilizing the time-quality relation. The finding shows the lean principles offer the elements of rapid construction synchronized with the elements of sustainability.Keywords: sustainable construction, rapid construction, time reduction, lean construction
Procedia PDF Downloads 2361934 Detergent Removal from Rinsing Water by Peroxi Electrocoagulation Process
Authors: A. Benhadji, M. Taleb Ahmed
Abstract:
Among the various methods of treatment, advanced oxidation processes (AOP) are the most promising ones. In this study, Peroxi Electrocoagulation Process (PEP) was investigated for the treatment of detergent wastewater. The process was compared with electrooxidation treatment. The results showed that chemical oxygen demand (COD) was high 7584 mgO2.L-1, while the biochemical oxygen demand was low (250 mgO2.L-1). This wastewater was hardly biodegradable. Electrochemical process was carried out for the removal of detergent using a glass reactor with a volume of 1 L and fitted with three electrodes. A direct current (DC) supply was used. Samples were taken at various current density (0.0227 A/cm2 to 0.0378 A/cm2) and reaction time (1-2-3-4 and 5 hour). Finally, the COD was determined. The results indicated that COD removal efficiency of PEP was observed to increase with current intensity and reached to 77% after 5 h. The highest removal efficiency was observed after 5 h of treatment.Keywords: AOP, COD, detergent, PEP, wastewater
Procedia PDF Downloads 1191933 Design and Modeling of Amphibious Houses for Flood Prone Areas: The Case of Nigeria
Authors: Onyebuchi Mogbo, Abdulsalam Mohammed, Salsabila Wali
Abstract:
This research discusses the design and modeling of an amphibious building. The amphibious building is a house with the function of floating during a flood event. Over the years, houses have been built to resist flood events some of which have failed. The floating house is designed to work with nature and not against it. In the event of a flood, the house will rise with the increasing water level and protect the house from sinking. For the design and modeling of this house an estimated cost of N250, 000, approximately $700, will be needed. It is expected that the house will rise when lightweight materials are incorporated in the design, and the concrete dock (in form of a hollow box) carrying the entire house in its hollow space is well designed. When there is flooding the water will fill up the concrete dock, and the house will rise upwards with vertical guides preventing it from moving side to side or out of its boundary. Architectural and Structural designs will be used in this project.Keywords: amphibious building, flood, housing, design and modelling
Procedia PDF Downloads 1801932 Effect of Water Hyacinth on Behaviour of Reinforced Concrete Beams
Authors: Ahmed Shaban Abdel Hay Gabr
Abstract:
Water hyacinth (W-H) has an adverse effect on Nile river in Egypt, it absorbs high quantities of water, it needs to serve these quantities especially at this time, so by burning W-H, it can be used in concrete mix to reduce the permeability of concrete and increase both the compressive and splitting strength. The effect of W-H on non-structural concrete properties was studied, but there is a lack of studies about the behavior of structural concrete containing W-H. Therefore, in the present study, the behavior of 15 RC beams with 100 x 150 mm cross section, 1250 mm span, different reinforcement ratios and different W-H ratios were studied by testing the beams under two-point bending test. The test results showed that Water Hyacinth is compatible with RC which yields promising results.Keywords: beams, reinforcement ratio, reinforced concrete, water hyacinth
Procedia PDF Downloads 4471931 Study of the Use of Artificial Neural Networks in Islamic Finance
Authors: Kaoutar Abbahaddou, Mohammed Salah Chiadmi
Abstract:
The need to find a relevant way to predict the next-day price of a stock index is a real concern for many financial stakeholders and researchers. We have known across years the proliferation of several methods. Nevertheless, among all these methods, the most controversial one is a machine learning algorithm that claims to be reliable, namely neural networks. Thus, the purpose of this article is to study the prediction power of neural networks in the particular case of Islamic finance as it is an under-looked area. In this article, we will first briefly present a review of the literature regarding neural networks and Islamic finance. Next, we present the architecture and principles of artificial neural networks most commonly used in finance. Then, we will show its empirical application on two Islamic stock indexes. The accuracy rate would be used to measure the performance of the algorithm in predicting the right price the next day. As a result, we can conclude that artificial neural networks are a reliable method to predict the next-day price for Islamic indices as it is claimed for conventional ones.Keywords: Islamic finance, stock price prediction, artificial neural networks, machine learning
Procedia PDF Downloads 2371930 Design Improvement of Aircraft Turbofan Engine Following Bird Ingestion Testing
Authors: Ahmed H. Elkholy
Abstract:
Aircraft gas turbine engines are subject to damage by airborne foreign objects such as birds and garbage dumps. In order to assess their effect on engine performance, a complete foreign object damage (FOD) test was carried out and a component failure analysis was used to verify airworthiness standards (AWS) requirements for engine certification as set by international regulations. Ingestion damage due to 1.8 Kg (4 lb.) bird strike on an engine is presented in some detail. Based on the observed damage, improvements to the engine design were suggested in two different locations: the front bearing housing and the low compressor shaft. When these improvements were implemented, the engine showed an acceptable containment capability that meets AWS requirements.Keywords: aircraft engine, airworthiness standards, bird ingestion, foreign object damage
Procedia PDF Downloads 4211929 Utilization of Learning Resources in Enhancing the Teaching of Science and Technology Courses in Post Primary Institutions in Nigeria
Authors: Isah Mohammed Patizhiko
Abstract:
This paper aimed at discussing the important role learning resources play in enhancing the teaching and learning of science and technology courses in post primary institution in Nigeria. The paper highlighted the importance learning resources contributed to the effective understanding of the learners. The use of learning resources in the teaching of these courses will encourage teachers to be more exploratory and the learners to have more understanding. In this paper, different range of learning resources particularly common learning resources (learning resources not design primarily for education purposes) to enrich their teaching. The paper also highlighted how ordinary resource can be turned into an educational resource. Recommendations were proffered in the sourcing of learning resources ie from the market, library, institutions, museums, and dump refuse and concluded that good demonstration on the use of resources will engage the learner’s interest and will develop higher level of conceptual understanding in the learning area.Keywords: enhance, learning, resources, science and technology, teaching
Procedia PDF Downloads 3981928 The Effect of Work Site Dangers on the Management of Construction Projects in Syria
Authors: Mohammed Aljoma, Eblal Zakzok
Abstract:
Safety is a science that seeks to protect and avoid humans from risks in any field and prevent losses in properties and lives as much as possible. On the other hand, occupational safety goals aim to protect workers from risks which can occur during work execution. The main purpose of occupational safety is to ultimately protect people, properties and the environment by reducing accidents and injuries that may cause losses and damages. To achieve this goal, we must remove the direct and indirect reasons which cause accidents and injuries; some of the reasons of accidents are the unsafe cases and inept behavior or both of them. This research focuses on the manner of providing instant protection from the very first beginning to people, properties and the environment by: -Inserting safety demands in the planning and designing works by identifying risk levels in every task of the project, -Using a new risk managing system or modifying or changing a previously-used one.Keywords: planning, scheduling, risk management, project duration, site safety
Procedia PDF Downloads 2971927 Exploring Wheel-Motion Energy Sources for Energy Harvesting Based on Electromagnetic Effect: Experimental and Numerical Investigation
Authors: Mohammed Alaa Alwafaie, Bela Kovacs
Abstract:
With the rapid emergence and evolution of renewable energy sources like wind and solar power, there is an increasing demand for effective energy harvester architectures. This paper focuses on investigating the concept of energy harvesting using a wheel-motion energy source. The proposed method involves the placement of magnets and copper coils inside the hubcap rod of a wheel. When the wheel is set in motion, following Faraday's Law, the movement of the magnet within the coil induces an electric current. The paper includes an experiment to measure the output voltage of electromagnetics, as well as a numerical simulation to further explore the potential of this energy harvesting approach. By harnessing the rotational motion of wheels, this research aims to contribute to the development of innovative techniques for generating electrical power in a sustainable and efficient manner.Keywords: harvesting energy, electromagnetic, hubcap rod wheel, magnet movement inside coil, faraday law
Procedia PDF Downloads 761926 Effect of Different Contact Rollers on the Surface Texture during the Belt Grinding Process
Authors: Amine Hamdi, Sidi Mohammed Merghache, Brahim Fernini
Abstract:
During abrasive machining of hard steels by belt grinding, the finished surface texture is influenced by the pressure between the abrasive belt and the workpiece; this pressure is the force applied by the contact roller on the workpiece. Therefore, the contact roller has an important role and has a direct impact on process efficiency. The objective of this article is to study and compare the influence of different contact rollers on the belt ground surface texture. The quality of the surface texture is characterized by eight roughness parameters (Ra, Rz, Rp, Rv, Rsk, Rku, Rsm, and Rdq) and five parameters of the bearing area curve (Rpk, Rk, Rvk, Mr1, and Mr2). The results of the experimental tests indicate a better surface texture obtained by the PA 6 polyamide roller (hardness 60 Shore D) compared to that obtained with other rollers of the same hardness or of different hardness. Simultaneously, optimum medium pressure between the belt and the workpiece allows chip removal without fracturing the abrasive grains. This generates a good surface texture.Keywords: belt grinding, contact roller, pressure, abrasive belt, surface texture
Procedia PDF Downloads 1831925 An Approach to Manage and Evaluate Asset Performance
Authors: Mohammed Saif Al-Saidi, John P. T. Mo
Abstract:
Modern engineering assets are complex and very high in value. They are expected to function for years to come, with ability to handle the change in technology and ageing modification. The aging of an engineering asset and continues increase of vendors and contractors numbers forces the asset operation management (or Owner) to design an asset system which can capture these changes. Furthermore, an accurate performance measurement and risk evaluation processes are highly needed. Therefore, this paper explores the nature of the asset management system performance evaluation for an engineering asset based on the System Support Engineering (SSE) principles. The research work explores the asset support system from a range of perspectives, interviewing managers from across a refinery organisation. The factors contributing to complexity of an asset management system are described in context which clusters them into several key areas. It is proposed that SSE framework may then be used as a tool for analysis and management of asset. The paper will conclude with discussion of potential application of the framework and opportunities for future research.Keywords: asset management, performance, evaluation, modern engineering, System Support Engineering (SSE)
Procedia PDF Downloads 6771924 Implementing Learner-Centered Teaching Approach In Iraqi Higher Education
Authors: Iman Ali Ahmed Al-Rashed
Abstract:
This paper directs attention to the limitations of the teacher-centered strategy in teaching. The aim of this study is to draw more educational attention to learner-centered strategy in order to shift the emphasis from the traditional concept of teaching to a new concept in teaching. To begin bridging the traditional concept of teaching and the new concept, the study will explore the new concept of teaching to support teaching in Arab World generally and in Iraq specifically. A qualitative case study orientation was used to collect data in the form of classroom observations, interviews and field notes. The teaching practices used by three university instructors are investigated and according to the findings, some explanations and recommendations are made.Keywords: case study, learner-centered strategy, qualitative study, teacher-centered strategy, traditional teaching
Procedia PDF Downloads 5481923 Chemical Modification of PVC and Its Surface Analysis by Means of XPS and Contact Angle Measurements
Authors: Ali Akrmi, Mohamed Beji, Ahmed Baklouti, Fatma Djouani, Philippe Lang, Mohamed M. Chehimi
Abstract:
Poly(vinyl chloride) (PVC) is a highly versatile polymer with excellent balance of properties and numerous applications such as water pipes, packaging and polymer materials of importance in the biomedical sector. However, depending on the applications, it is necessary to modify PVC by mixing with a plasticizer; surface modification using plasma, surface grafting or flame treatment; or bulk chemical modification which affects the entire PVC chains at an extent that can be tuned by the polymer chemist. The targeted applications are improvement of chemical resistance, avoiding or limitation of migration of toxic plasticizers, improvement of antibacterial properties, or control of blood compatibility.Keywords: poly(vinyl chloride), nucleophilic substitution, sulfonylcarbamates, XPS
Procedia PDF Downloads 7041922 Noise Removal Techniques in Medical Images
Authors: Amhimmid Mohammed Saffour, Abdelkader Salama
Abstract:
Filtering is a part of image enhancement techniques, it is used to enhance certain details such as edges in the image that are relevant to the application. Additionally, filtering can even be used to eliminate unwanted components of noise. Medical images typically contain salt and pepper noise and Poisson noise. This noise appears to the presence of minute grey scale variations within the image. In this paper, different filters techniques namely (Median, Wiener, Rank order3, Rank order5, and Average) were applied on CT medical images (Brain and chest). We using all these filters to remove salt and pepper noise from these images. This type of noise consists of random pixels being set to black or white. Peak Signal to Noise Ratio (PSNR), Mean Square Error r(MSE) and Histogram were used to evaluated the quality of filtered images. The results, which we have achieved shows that, these filters, are more useful and they prove to be helpful for general medical practitioners to analyze the symptoms of the patients with no difficulty.Keywords: CT imaging, median filter, adaptive filter and average filter, MATLAB
Procedia PDF Downloads 3131921 Mathematical Modeling of the Water Bridge Formation in Porous Media: PEMFC Microchannels
Authors: N. Ibrahim-Rassoul, A. Kessi, E. K. Si-Ahmed, N. Djilali, J. Legrand
Abstract:
The static and dynamic formation of liquid water bridges is analyzed using a combination of visualization experiments in a microchannel with a mathematical model. This paper presents experimental and theoretical findings of water plug/capillary bridge formation in a 250 μm squared microchannel. The approach combines mathematical and numerical modeling with experimental visualization and measurements. The generality of the model is also illustrated for flow conditions encountered in manipulation of polymeric materials and formation of liquid bridges between patterned surfaces. The predictions of the model agree favorably the observations as well as with the experimental recordings.Keywords: green energy, mathematical modeling, fuel cell, water plug, gas diffusion layer, surface of revolution
Procedia PDF Downloads 5301920 Cloud Effect on Power Generation of Grid-Connected Small PV Systems
Authors: Yehya Abdellatif, Ahmed Alsalaymeh, Iyad Muslih, Ali Alshduifat
Abstract:
Photovoltaic (PV) power generation systems, mainly small scale, are rapidly being deployed in Jordan. The impact of these systems on the grid has not been studied or analyzed. These systems can cause many technical problems such as reverse power flows and voltage rises in distribution feeders, and real and reactive power transients that affect the operation of the transmission system. To fully understand and address these problems, extensive research, simulation, and case studies are required. To this end, this paper studies the cloud shadow effect on the power generation of a ground mounted PV system installed at the test field of the Renewable Energy Center at the Applied Science University.Keywords: photovoltaic, cloud effect, MPPT, power transients
Procedia PDF Downloads 5991919 A Strategy of Direct Power Control for PWM Rectifier Reducing Ripple in Instantaneous Power
Authors: T. Mohammed Chikouche, K. Hartani
Abstract:
Based on the analysis of basic direct torque control, a parallel master slave for four in-wheel permanent magnet synchronous motors (PMSM) fed by two three phase inverters used in electric vehicle is proposed in this paper. A conventional system with multi-inverter and multi-machine comprises a three phase inverter for each machine to be controlled. Another approach consists in using only one three-phase inverter to supply several permanent magnet synchronous machines. A modified direct torque control (DTC) algorithm is used for the control of the bi-machine traction system. Simulation results show that the proposed control strategy is well adapted for the synchronism of this system and provide good speed tracking performance.Keywords: electric vehicle, multi-machine single-inverter system, multi-machine multi-inverter control, in-wheel motor, master-slave control
Procedia PDF Downloads 2211918 Investigation of Modified Microporous Materials for Environmental Depollution
Authors: Souhila Bendenia, Chahrazed Bendenia, Hanaa Merad-Dib, Sarra Merabet, Samia Moulebhar, Sid Ahmed Khantar
Abstract:
Today, environmental pollution is a major concernworldwide, threateninghumanhealth. Various techniques have been used, includingdegradation, filtration, advancedoxidationprocesses, ion exchange, membrane processes, and adsorption. The latter is one of the mostsuitablemethods, usinghighly efficient materials. In this study, NaX zeolite was modified with Cu or Ni at various rates. Following ion exchange, the samples were characterized by XRD, BET and SEM/EDX. After characterization, the exchanged zeolites were used for adsorption of various pollutants as CO2. Different thermodynamic parameters were studied such as Qst. XRD results show that the most intense peaks characteristic of 13X persist after the exchange reaction for all samples. The SEM images of our samples have uniform and regular crystal shapes. The results show that ion exhange with Cu or Ni affect the textural properties of X zeolites and prove that the exchange zeolites can be used as an adsorbent for depollution.Keywords: X zeolites (NaX), ion exchange, characterization, adsorption
Procedia PDF Downloads 871917 The Investigation of Psychological Motives of Creative Abilities in the Omani Musical Intelligence
Authors: Mohammed Talib Alkiyumi
Abstract:
The Sultanate of Oman is characterized by a huge musical heritage that remains mostly preserved. 142 different traditional musical genres and styles (funun) have been registered in the Sultanate. This large number is a unique phenomenon that is worthy of attention and study. These genres and styles are different from others in their origins, rhythms, melodies, poetry, dance movements, etc. Certainly, Oman is exposed to other cultures and there is a variety of ethnicities in the Sultanate; however, this musical diversity is mostly an Omani product. This paper investigates the psychological motives behind Omani musical creativity. This qualitative study is based on relevant documents, as well as an analysis of Omani performance in those genres through documentary films and direct observations. Musical genres are performed in social events such as weddings and celebrations; however, research has shown psychological motives that motivated Omani people to create these various genres, such as provocation of enthusiasm, meditation, religious motivations, poetic competition, and emotional motivation. For each motive, musical genres have been presented.Keywords: traditional musical, creativity, musical intelligence, Sultanate of Oman
Procedia PDF Downloads 1031916 Beta Titanium Alloys: The Lowest Elastic Modulus for Biomedical Applications: A Review
Authors: Mohsin Talib Mohammed, Zahid A. Khan, Arshad N. Siddiquee
Abstract:
Biometallic materials are the most important materials for use in biomedical applications especially in manufacturing a variety of biological artificial replacements in a modern worlds, e.g. hip, knee or shoulder joints, due to their advanced characteristics. Titanium (Ti) and its alloys are used extensively in biomedical applications based on their high specific strength and excellent corrosion resistance. Beta-Ti alloys containing completely biocompatible elements are exceptionally prospective materials for manufacturing of bioimplants. They have superior mechanical, chemical and electrochemical properties for use as biomaterials. These biomaterials have the ability to introduce the most important property of biochemical compatibility which is low elastic modulus. This review examines current information on the recent developments in alloying elements leading to improvements of beta Ti alloys for use as biomaterials. Moreover, this paper focuses mainly on the evolution, evaluation and development of the modulus of elasticity as an effective factor on the performance of beta alloys.Keywords: beta alloys, biomedical applications, titanium alloys, Young's modulus
Procedia PDF Downloads 3251915 Molecular Junctions between Graphene Strips: Electronic and Transport Properties
Authors: Adel Belayadi, Ahmed Mougari, Boualem Bourahla
Abstract:
Molecular junctions are currently considered a promising style in the miniaturization of electronic devices. In this contribution, we provide a tight-binding model to investigate the quantum transport properties across-molecular junctions sandwiched between 2D-graphene nanoribbons in the zigzag direction. We investigate, in particular, the effect of embedded atoms such as Gold and Silicon across the molecular junction. The results exhibit a resonance behavior in terms of incident Fermi levels, depending on the molecular junction type. Additionally, the transport properties under a perpendicular magnetic field exhibit an oscillation for the transmittance versus the magnetic field strength.Keywords: molecular junction, 2D-graphene nanoribbons, quantum transport properties, magnetic field
Procedia PDF Downloads 961914 Easy Method of Synthesis and Functionalzation of Zno Nanoparticules With 3 Aminopropylthrimethoxysilane (APTES)
Authors: Haythem Barrak, Gaetan Laroche, Adel M’nif, Ahmed Hichem Hamzaoui
Abstract:
The use of semiconductor oxides, as chemical or biological, requires their functionalization with appropriate dependent molecules of the substance to be detected. generally, the support materials used are TiO2 and SiO2. In the present work, we used zinc oxide (ZnO) known for its interesting physical properties. The synthesis of nano scale ZnO was performed by co-precipitation at low temperature (60 ° C).To our knowledge, the obtaining of this material at this temperature was carried out for the first time. This shows the low cost of this operation. On the other hand, the surface functionalization of ZnO was performed with (3-aminopropyl) triethoxysilane (APTES) by using a specific method using ethanol for the first time. In addition, the duration of this stage is very low compared to literature. The samples obtained were analyzed by XRD, TEM, DLS, FTIR, and TGA shows that XPS that the operation of grafting of APTES on our support was carried out with success.Keywords: functionalization, nanoparticle, ZnO, APTES, caractérisation
Procedia PDF Downloads 3611913 Thermal Conductivity of Al2O3/Water-Based Nanofluids: Revisiting the Influences of pH and Surfactant
Authors: Nizar Bouguerra, Ahmed Khabou, Sébastien Poncet, Saïd Elkoun
Abstract:
The present work focuses on the preparation and the stabilization of Al2O3-water based nanofluids. Though they have been widely considered in the past, to the best of our knowledge, there is no clear consensus about a proper way to prepare and stabilize them by the appropriate surfactant. In this paper, a careful experimental investigation is performed to quantify the combined influence of pH and the surfactant on the stability of Al2O3-water based nanofluids. Two volume concentrations of nanoparticles and three nanoparticle sizes have been considered. The good preparation and stability of these nanofluids are evaluated through thermal conductivity measurements. The results show that the optimum value for the thermal conductivity is obtained mainly by controlling the pH of the mixture and surfactants are not necessary to stabilize the solution.Keywords: nanofluid, thermal conductivity, pH, transient hot wire, surfactant, Al2O3, stability, dispersion, preparation
Procedia PDF Downloads 3561912 Optimization of Vertical Axis Wind Turbine Based on Artificial Neural Network
Authors: Mohammed Affanuddin H. Siddique, Jayesh S. Shukla, Chetan B. Meshram
Abstract:
The neural networks are one of the power tools of machine learning. After the invention of perceptron in early 1980's, the neural networks and its application have grown rapidly. Neural networks are a technique originally developed for pattern investigation. The structure of a neural network consists of neurons connected through synapse. Here, we have investigated the different algorithms and cost function reduction techniques for optimization of vertical axis wind turbine (VAWT) rotor blades. The aerodynamic force coefficients corresponding to the airfoils are stored in a database along with the airfoil coordinates. A forward propagation neural network is created with the input as aerodynamic coefficients and output as the airfoil co-ordinates. In the proposed algorithm, the hidden layer is incorporated into cost function having linear and non-linear error terms. In this article, it is observed that the ANNs (Artificial Neural Network) can be used for the VAWT’s optimization.Keywords: VAWT, ANN, optimization, inverse design
Procedia PDF Downloads 3231911 Implementing Fault Tolerance with Proxy Signature on the Improvement of RSA System
Authors: H. El-Kamchouchi, Heba Gaber, Fatma Ahmed, Dalia H. El-Kamchouchi
Abstract:
Fault tolerance and data security are two important issues in modern communication systems. During the transmission of data between the sender and receiver, errors may occur frequently. Therefore, the sender must re-transmit the data to the receiver in order to correct these errors, which makes the system very feeble. To improve the scalability of the scheme, we present a proxy signature scheme with fault tolerance over an efficient and secure authenticated key agreement protocol based on the improved RSA system. Authenticated key agreement protocols have an important role in building a secure communications network between the two parties.Keywords: fault tolerance, improved RSA, key agreement, proxy signature
Procedia PDF Downloads 4251910 Corporate Social Responsibility and Dividend Policy
Authors: Mohammed Benlemlih
Abstract:
Using a sample of 22,839 US firm-year observations over the 1991-2012 period, we find that high CSR firms pay more dividends than low CSR firms. The analysis of individual components of CSR provides strong support for this main finding: five of the six individual dimensions are also associated with high dividend payout. When analyzing the stability of dividend payout, our results show that socially irresponsible firms adjust dividends more rapidly than socially responsible firms do: dividend payout is more stable in high CSR firms. Additional results suggest that firms involved in two controversial activities -the military and alcohol - are associated with low dividend payouts. These findings are robust to alternative assumptions and model specifications, alternative measures of dividend, additional control, and several approaches to address endogeneity. Overall, our results are consistent with the expectation that high CSR firms may use dividend policy to manage the agency problems related to overinvestment in CSR.Keywords: corporate social responsibility, dividend policy, Lintner model, agency theory, signaling theory, dividend stability
Procedia PDF Downloads 2651909 3D Building Model Utilizing Airborne LiDAR Dataset and Terrestrial Photographic Images
Authors: J. Jasmee, I. Roslina, A. Mohammed Yaziz & A.H Juazer Rizal
Abstract:
The need of an effective building information collection method is vital to support a diversity of land development activities. At present, advances in remote sensing such as airborne LiDAR (Light Detection and Ranging) is an established technology for building information collection, location, and elevation of the reflecting laser points towards the construction of 3D building models. In this study, LiDAR datasets and terrestrial photographic images of buildings towards the construction of 3D building models is explored. It is found that, the quantitative accuracy of the constructed 3D building model, namely in the horizontal and vertical components were ± 0.31m (RMSEx,y) and ± 0.145m (RMSEz) respectively. The accuracies were computed based on sixty nine (69) horizontal and twenty (20) vertical surveyed points. As for the qualitative assessment, it is shown that the appearance of the 3D building model is adequate to support the requirements of LOD3 presentation based on the OGC (Open Geospatial Consortium) standard CityGML.Keywords: LiDAR datasets, DSM, DTM, 3D building models
Procedia PDF Downloads 3201908 Assessing Basic Computer Applications’ Skills of College-Level Students in Saudi Arabia
Authors: Mohammed A. Gharawi, Majed M. Khoja
Abstract:
This paper is a report on the findings of a study conducted at the Institute of Public Administration (IPA) in Saudi Arabia. The paper applied both qualitative and quantitative research methods to assess the levels of basic computer applications’ skills among students enrolled in the preparatory programs of the institution. qualitative data have been collected from semi-structured interviews with the instructors who have previously been assigned to teach Introduction to information technology courses. Quantitative data were collected by executing a self-report questionnaire and a written statistical test. 380 enrolled students responded to the questionnaire and 142 accomplished the statistical test. The results indicate the lack of necessary skills to deal with computer applications among most of the students who are enrolled in the IPA’s preparatory programs.Keywords: assessment, computer applications, computer literacy, Institute of Public Administration, Saudi Arabia
Procedia PDF Downloads 3151907 3D Simulation for Design and Predicting Performance of a Thermal Heat Storage Facility using Sand
Authors: Nadjiba Mahfoudi, Abdelhafid Moummi , Mohammed El Ganaoui
Abstract:
Thermal applications are drawing increasing attention in the solar energy research field, due to their high performance in energy storage density and energy conversion efficiency. In these applications, solar collectors and thermal energy storage systems are the two core components. This paper presents a thermal analysis of the transient behavior and storage capability of a sensible heat storage device in which sand is used as a storage media. The TES unit with embedded charging tubes is connected to a solar air collector. To investigate it storage characteristics a 3D-model using no linear coupled partial differential equations for both temperature of storage medium and heat transfer fluid (HTF), has been developed. Performances of thermal storage bed of capacity of 17 MJ (including bed temperature, charging time, energy storage rate, charging energy efficiency) have been evaluated. The effect of the number of charging tubes (3 configurations) is presented.Keywords: design, thermal modeling, heat transfer enhancement, sand, sensible heat storage
Procedia PDF Downloads 561