Sami Mohamed Sharif

Sami Mohamed Sharif
University of Khartoum · Department of Electrical and Electronic Engineering

B.Sc., Ph.D.

About

57
Publications
18,488
Reads
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448
Citations
Citations since 2016
10 Research Items
236 Citations
2016201720182019202020212022010203040
2016201720182019202020212022010203040
2016201720182019202020212022010203040
2016201720182019202020212022010203040
Introduction
Sami Sharif is a Professor with the Department of Electrical Engineering, University of Khartoum (UofK). His current research interests include: Networking, Switching and teletraffic engineering, Radio wave propagation, Electromagnetic, Information Technology and Communications, Electronic Systems, ICT Economics and regulation.
Additional affiliations
January 1986 - present
University of Bradford
Position
  • Research Assistant
January 1981 - present
University of Khartoum
Position
  • Professor (Full)
Description
  • Professor of Communication and Information Systems
January 1981 - present
University of Khartoum
Position
  • Professor (Full)
Description
  • Professor of communication and information systems

Publications

Publications (57)
Conference Paper
Algorithms and architectures for performing modular multiplication operations are important in residue number system and cryptography. In this paper a new algorithm of Radix-4 MSB modular multiplier using 4-2 compressor is presented. The recoding rules for the radix-4 Booth's algorithm are used to reduce the number of partial products and improve t...
Article
Full-text available
The study of electromagnetic signals propagation through dusty media (dust storms, air with suspended dust particles), requires knowledge of some of the electrical and mechanical properties of that media. The aim of this paper is to describe the dusty media properties related to microwave signal propagation, and to give numerical values and statis...
Article
Full-text available
Chemical analysis is carried out for dust sample collected from central Sudan and the dust chemical constituents are obtained. The mineral composition of dust are identified by the X-ray diffraction techniques. The mineral quantities are obtained by a technique developed based on the chemical analytical methods. Analyses show that quartz is the dom...
Presentation
Full-text available
نظرة عامة لاستخدام انترنت الاشياء في صناعة الطاقة
Conference Paper
The aim of this paper is to present a new technique that may be used to determine the wavelet detail coefficient in a simple and fast manner. This technique eliminates the need for applying two filters by estimating the detail coefficients from approximation coefficients. The technique is applied to the frame size of video traces with different gro...
Article
Wireless Sensor Network WSN is a network that consists of a number of sensors nodes, each node is a combination of a sensor, microcontroller, memory unit, and transceiver module. WSN have many useful applications such as remote monitoring, medicine, military and in chemical processing. The power consumption is a great challenge in WSN, which can be...
Article
Full-text available
The aim of this paper is to investigate the statistical properties of H.264/AVC video sequences. The stationarity, dependence properties and self-similarity are investigated. Analysis of the H.264/AVC video sequences variable bit rate (VBR) traffic has shown that this data has strong self-similarity properties as well as noticeable long range depen...
Conference Paper
In Long Term Evolution (LTE) system the Tracking Area (TA) is a group of cells in which User Equipment (UE) may move freely without performing location update process. The TA scheme has many limitations such as ping-pong effect and massive mobility signaling congestion. To overcome the limitations of the TA scheme, Tracking Area List (TAL) scheme i...
Article
Full-text available
A realistic model is developed to predict the specific attenuation when electromagnetic signals propagate through dusty media (dust storms). The model is based on Mie approximation for the scattering of electromagnetic signal by a spherical particle. Variation of the dust particles dimensions is considered in this model. Reliable published values f...
Article
Full-text available
: This paper reviews the private next generation networks (NGN) , billing and charging system and clarify the billing and charging system and compared with traditional telecommunications billing system. The paper also contains the NGN billing and charging system mathematical model so as to understand the NGN billing process.
Article
Full-text available
This white paper will help service providers understand the benefits and economics associated with implementing a Next Generation Network (NGN). Convergence is the process of interconnection of traditional switched circuit networks (the PSTN and mobile networks) and packet-switched networks based on the Internet Protocol (IP) for routing. Network...
Article
Full-text available
This paper represents the Quality of Service (QOS) in next generation network. We outline primarily standardized QOS control architectures with respect to the service and transport strata of NGN. And discuss the conditions of QOS in NGN connectivity and QOS in NGN user terminals. This information is useful regarding the identification of adequate Q...
Article
In Long Term Evolution systems (LTE) the concept of Tracking Area List (TAL) is introduced. TAL consists of a group of Tracking Areas (TAs), and it is assigned to a User Equipment (UE), the UE does not need to register its location when it moves within TAs of the assigned TAL. If an optimum TAL design is implemented this may result in the reduction...
Article
Full-text available
In Long Term Evolution systems (LTE) the concept of Tracking Area List (TAL) is introduced. TAL consists of a group of Tracking Areas (TAs), and it is assigned to a User Equipment (UE), the UE does not need to register its location when it moves within TAs of the assigned TAL. If an optimum TAL design is implemented this may result in the reduction...
Conference Paper
High frequency propagation model for Sudan and South Sudan in term of the optimum frequency was designed based on the International Reference Ionosphere (IRI). The model simulates the effect of changing atmospheric properties during day and night on the Sudanese ionospheric links in term of the optimum frequency. More than 140 HF links in Sudan wer...
Conference Paper
This research focuses on the comparison of two commonly used receiver initiated Dynamic Load Balancing (DLB) Schemes. The schemes of which are the ARR (Asynchronous Round Robin) and RP (Random Polling) are comprehensively compared theoretically and practically, weighing their pros and cons. To present a case study for their application and thus com...
Article
Full-text available
This paper presents an approach to integrate learning styles into adaptive e-learning hypermedia. The main objective was to develop an adaptive e-learning system and assess the effect of adapting educational materials individualized to the student’s learning style. The proposed approach utilized adaptive hypermedia technology to improve learning pr...
Article
Full-text available
Advances in information and communication technologies led to the emerging of modern digital systems which facilitate sharing of information and innovations. These systems are thus supportive to the Sudanese cultural "collective" memory institutions as a collective memory bank of the nation achievements and indigenous knowledge. This article aims t...
Article
Effective traffic measurement algorithms are of critical importance to properly design and implement computer networks and network services like the World Wide Web. This paper proposes a traffic measurement algorithm for self similar traffic: Adaptive multistage filters algorithm. This algorithm uses multistage filters and adaptation mechanism to c...
Article
Full-text available
Advances in information and communication technologies led to the emerging of modern digital systems which facilitate sharing and preservation of information and innovations. These systems are thus supportive to cultural "collective" memory of the Nation which is local repository of explicit and tacit knowledge. This paper aims to study these digit...
Article
Full-text available
Effective traffic measurement algorithms are of critical importance to properly design and implement computer networks and network services like the World Wide Web. This paper proposes a traffic measurement algorithm for self similar traffic: Adaptive multistage filters algorithm. This algorithm uses multistage filters and adaptation mechanism to c...
Conference Paper
Full-text available
Africa is the second largest content in the world, with population 967 million people (as of 2008) in 61 territories, which accounts for about 14% of the world's human population. About 300 million people live in poverty in Africa and the World Bank estimates that African economies would need to grow by five percent a year just to keep this number...
Conference Paper
Traditional time series models such as ARIMA models have been proven to be inadequate for modelling traffic exhibiting long-range dependance. In this paper we present a new model the adjusted ARIMA model for modelling long-range dependant Internet traffic. The AARIMA model is suggested to give a quick and simple way to model Internet traffic by ret...
Article
Full-text available
It is now well known that Internet traffic exhibits self-similarity, which cannot be described by traditional Markovian models such as the Poisson process. The causes of self-similarity of network traffic must be identified because understanding the nature of network traffic is critical in order to properly design and implement computer networks an...
Article
Full-text available
Previous studies of Internet traffic have shown that a very small percentage of flows consume most of the network bandwidth. It is important to take such flows into account when measuring the network traffic self-similarity. This paper proposes a traffic measurement algorithm for self similar traffic: Adaptive sampling algorithm. This algorithm use...
Article
Full-text available
This paper represents the achieved results of propagation measurements which were carried out to investigate the excess attenuation of radio signal at 2.1 GHz through Date Palm trees in North of Abu Dhabi city, United Arab Emirates (UAE). The obtained experimental results have been used to evaluate some existing vegetation attenuation models, Expon...
Article
Full-text available
A computer software is developed to display the magnetic and electric fields of hertzian and/or half-wave dipole antennas systems. Using this program, the performance of any hertzian and/or half-wave dipole antennas array may be investigated and studied. The general analytical expressions for the electrical and magnetic fields strengths, at arbitra...
Article
Full-text available
The performance of some wire antenna systems is investigated at 3 GHz frequency. Five antenna systems are considered, all systems have a half-wave dipole as driven element, but different reflector geometry. The effects of the antenna parameters such as number of directors, spacing between elements, position of the driven element, etc. are investiga...
Article
Chemical analysis is carried out for dust sample collected from central Sudan and the dust chemical constituents are obtained. The mineral composition of dust are identified by the Xray diffraction techniques. The mineral quantities are obtained by a technique developed based on the chemical analytical methods. Analyses show that Quartz is the domi...
Conference Paper
Full-text available
Handles the backscatter problem of the dusty medium in a similar way to that of Goldhirsh (1982). Nevertheless, the parameters needed to study the backscatter properties of the dusty medium are measured and revealed, which gives a more realistic solution for the problem in hand. Expressions to predict the backscattering cross-section area and clutt...
Article
Full-text available
Introduction: Due to the rapid expansion in communication systems, methods have been sought for optimal utilization of the frequency spectrum. This has led to the adoption of frequency re-use technique employing dual-polarizations as exemplified in Arabsat system. In system using this technique, signals which are opposite-hand circular or crossed l...
Article
Full-text available
Some of the electrical and mechanical properties of dust are discussed. An expression for optical visibility during storms is given in terms of the relative volume occupied by dust. Expressions for attenuation and phase shift constants for a medium with precipitating dust particles are derived in terms of visibility and wavelength for both vertical...
Article
Full-text available
The particle-size distribution (PSD) of dust samples collected in Sudan is studied. The analysis of the sample PSD is carried by hydrometer and pipette methods; which are based on the sedimentation of the particles in water. The measurements have shown that dust may contain particles with equivalent diameter in the range from 0.1 to 300 micron. The...
Article
The dielectric constant of dust was measured under different conditions to determine the effects of hygroscopic water, chemical composition, and frequency. Hygroscopic water increases both real and imaginary parts of the dielectric constant. Water contents as low as 4.8% by weight cause the real part to increase by 48% and imaginary part by over 60...
Article
Full-text available
Measurement of the dielectric constant of dust at 8.3 GHz was carried using a cavity technique. Four dust samples were used and an average value of 4.05+0.08 for the real part of the permittivity was obtained. An average value of 0.084+0.015 for the imaginary part was observed.
Conference Paper
Measurement of the dielectric constant of dust at 8.3 GHz was carried using a cavity technique. Four dust samples were used and an average value of 4.05+0.08 for the real part of the permittivity was obtained. An average value of 0.084+0.015 for the imaginary part was observed.
Article
Full-text available
Because autocorrelation functions play an important role in stochastic processes and can be used to model the traffic data practically, it is significant to study how to find a function that best fits the autocorrelation sequence of a real-traffic trace. This paper presents a asymptotic model for autocorrelation functions using Weighted non-linear...
Article
The attenuation introduced by rain is discussed in this paper. The rainfall rate distribution needed by the prediction models are measured and obtained for 15 stations in Sudan. The data used to find the rate distributions is collected over 20 years. For the purpose of attenuation estimation the country is divided into five rain zones. The attenuat...
Article
Full-text available
This paper is discussing the design and implementation of embedded computer based control system for a banknote-numbering machine, "Numerota". The design is based on the embedded system ELAN-104NC with windows CE preinstalled in it. ELAN is a single board PC with inputs outputs cards; it is a rack mounted system. The application software is designe...
Article
In this paper a new model the Adjusted Autoregres- sive Integrated Moving Average (AARIMA) model for predicting Internet traffic is introduced. The steps that can be used to obtain the model are detailed. Real Internet traffic traces are used to estimate and test the models. The AARIMA model is shown to capture the local self-similarity using wavel...
Article
Full-text available
A General Regression Neural Network (iterative model) was trained and taught to predict land cover features obtained from remotely sensed data. Training patterns have been generated from bands 1 and 4 of the Landsat-7 ETM+ imaging system (2000). Traditional digital image processing techniques were used to create the training and test patterns as we...
Article
Full-text available
Clutter and backscatter cross-section due to dust storms are computed for frequencies at the x-band. Expression are derived for the operation parameters (i) echo (clutter) power, and (ii) backscattering cross-section. The variation of these parameters are given for different storms visibilities and radar ranges. The propagation medium parameters ne...
Article
Full-text available
This paper presents an approach to integrate learning styles into adaptive e-learning hypermedia. The main objective was to develop an adaptive e-learning system and assess the effect of adapting educational materials individualized to the student's learning style. The proposed approach utilized adaptive hypermedia technology to improve learning pr...

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Projects (4)
Archived project
Project
I want to benefit from the quadrature mirror filter properties in data traffic statistical modelling.