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Adaptive Compensator Of Single State Elastoplastic Friction Model, A. A. Abouelsoud, J. Abdo, R. Zaier Apr 2025

Adaptive Compensator Of Single State Elastoplastic Friction Model, A. A. Abouelsoud, J. Abdo, R. Zaier

The Journal of Engineering Research

A nonlinear friction is an unavoidable phenomenon frequently experienced in mechanical system between two contact surfaces. An adaptive compensator is designed to achieve tracking of a desired velocity trajectory in the presence of friction force described by a single state elastoplastic friction model. The adaptive compensator includes an adaptive observer and a computed force controller. The closed loop system is shown to be stable using Lyapunov second method. Simulation results show the effectiveness of the proposed compensator.

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Effective Flange Width For Composite Steel Beams, T. Salama, H.H. Nassif Apr 2025

Effective Flange Width For Composite Steel Beams, T. Salama, H.H. Nassif

The Journal of Engineering Research

The effective flange width is a concept proposed by various codes to simplify the computation of stress distribution across the width of composite beams. Questions have been raised as to the validity of the effective slab width provisions, since they have a direct effect on the computed ultimate moment as well as serviceability limit states such as deflection, fatigue, and overloading. The objective of this paper is to present results from an experimental and analytical investigation to determine the effective slab width in steel composite beams. The Finite Element Method (FEM) was employed for the analysis of composite steel-concrete beams …

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Class-E Amplifier Design Improvements For Gsm Frequencies, Z. Nadir, F. Touati Apr 2025

Class-E Amplifier Design Improvements For Gsm Frequencies, Z. Nadir, F. Touati

The Journal of Engineering Research

Efficient power amplifiers are essential in portable battery-operated systems such as mobile phones. Also, the power amplifier (PA) is the most power-consuming building block in the transmitter of a portable system. This paper investigates how the efficiency of the power amplifier (which is beneficial for multiple applications in communcation sector) can be improved by increasing the efficiency of switching mode class E power amplifiers for frequencies of 900 MHz and 1800 MHz. The paper tackles modeling, design improvements and verification through simulation for higher efficiencies. This is the continuation of previous work by the authors. These nonlinear power amplifiers can …

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A General Model For Describing The Performance Of Brushless Doubly-Fed Induction Machines, S. M. Allam, A. M. Azmy, M. A. El-Khazendar Apr 2025

A General Model For Describing The Performance Of Brushless Doubly-Fed Induction Machines, S. M. Allam, A. M. Azmy, M. A. El-Khazendar

The Journal of Engineering Research

This paper presents a generalized model, by which the dynamic and steady-state behaviour of the Brushless Doubly-Fed Induction Machine (BDFIM) can be precisely predicted. The investigated doubly-fed machine has two sets of three-phase stator windings with different pole numbers. The rotor is a squirrel-cage type with a simple modification in order to support the two air-gap rotating fields that are produced by the stator windings and have different pole numbers. The machine model is derived in the qdo-axis variables. The qdoaxes are attached to rotor and hence, it rotates at the rotor speed (

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Mutual Coupling Reduction Between Axial-Mode Helical Antennas Using Single-Negative (Sng) Magnetic Metamaterials, M. M. Bait-Suwailam, O.M. Ramahi Apr 2025

Mutual Coupling Reduction Between Axial-Mode Helical Antennas Using Single-Negative (Sng) Magnetic Metamaterials, M. M. Bait-Suwailam, O.M. Ramahi

The Journal of Engineering Research

This paper investigates the mutual coupling effects between axial-mode helical antenna arrays. Single-negative (SNG) magnetic metamaterials are developed and used in this work in order to reduce mutual coupling between axial-mode helical antennas used in multiple-input multiple-output systems. The inclusions considered here are composed of broadside coupled split-ring resonators. The magnetic permeability of those SNG inclusions have complex effective magnetic permeability response over a frequency band with high negative real part above the resonance and positive real part below the resonance. The SNG resonators are inserted between closely-spaced axial-mode helical antenna elements. Effective responses of the constitutive parameters of the …

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Mimo Channel Gain Mechanisms Relative To Siso Channel, A. A. Abouda, N.G. Tarhuni Apr 2025

Mimo Channel Gain Mechanisms Relative To Siso Channel, A. A. Abouda, N.G. Tarhuni

The Journal of Engineering Research

In contrast to the rest of wireless communication technologies, multiple-input multiple-output (MIMO) technology enjoys different gain mechanisms that make it very attractive for reliable high data rate wireless communications. This paper presents a study on these gain mechanisms with particular emphasis on the case of high average received signal to noise ratio (SNR) where the MIMO system deployment is most promising. We write the MIMO channel capacity in terms of gains relative to a single- input single-output (SISO) wireless channel. Doing so, spatial multiplexing gain and power gain of MIMO wireless channels become more insightful. Based on this analysis a …

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Design Of A Realistic Test Simulator For A Built-In Self Test Environment, A. Ahmad, Muscat, Sultanate Of Oman, D. Al-Abri, Muscat, Sultanate Of Oman Apr 2025

Design Of A Realistic Test Simulator For A Built-In Self Test Environment, A. Ahmad, Muscat, Sultanate Of Oman, D. Al-Abri, Muscat, Sultanate Of Oman

The Journal of Engineering Research

This paper presents a realistic test approach suitable to Design For Testability (DFT) and Built- In Self Test (BIST) environments. The approach is culminated in the form of a test simulator which is capable of providing a required goal of test for the System Under Test (SUT). The simulator uses the approach of fault diagnostics with fault grading procedure to provide the tests. The tool is developed on a common PC platform and hence no special software is required. Thereby, it is a low cost tool and hence economical. The tool is very much suitable for determining realistic test sequences …

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A Multi-Resolution Texture Image Retrieval Using Fast Fourier Transform, A. Abdesselam Apr 2025

A Multi-Resolution Texture Image Retrieval Using Fast Fourier Transform, A. Abdesselam

The Journal of Engineering Research

Texture is an important visual property that characterizes a wide range of natural and artificial images which makes it a useful feature for retrieving images. Several approaches have been proposed to describe the texture contents of an image. In early research works, such as edge histograms-based techniques and co-occurrence-based approaches, texture descriptors were mainly extracted from the spatial domain. Later on, dual spaces (transform of spatial domain) such as frequency space or spaces resulting from Gabor or wavelet transforms were explored for texture characterization. Recent physiological studies showed that human visual system can be modeled as a set of independent …

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Determination Of Potential Profile In Planar Electronic Structures Using A Semi-Analytical Technique, Hadj Bourdoucen, Mokrane Dehmas, El-Bachir Yallaoui Apr 2025

Determination Of Potential Profile In Planar Electronic Structures Using A Semi-Analytical Technique, Hadj Bourdoucen, Mokrane Dehmas, El-Bachir Yallaoui

The Journal of Engineering Research

In this paper, a semi-analytical technique known as the Method of Lines (MoL) with uniform and non-uniform discretization schemes is developed. The aim is to determine static potential profile in planar electronic structures. Even though this method has been known for some time, there has been reported work on its application to planar semiconductor device analysis for voltage profile determination. Since most current electronic devices are manufactured using planar and quasi-planar technology, the proposed algorithm is well suited for device analysis prior to fabrication. Compared with known popular methods such as Finite Difference and Finite Elements methods, the proposed technique …

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A Less Complex Algorithmic Procedure For Computing Gray Codes, Afaq Ahmad, Mohammed M. Bait Suwailam Apr 2025

A Less Complex Algorithmic Procedure For Computing Gray Codes, Afaq Ahmad, Mohammed M. Bait Suwailam

The Journal of Engineering Research

The purpose of this paper is to present a new and faster algorithmic procedure for generating the n bi Gray codes. Thereby, through this paper we have presented the derivation, design and implementation of a newly developed algorithm for the generation of an n-bit binary reflected Gray code sequences. The developed algorithm is stemmed from the fact of generating and properly placing the min-terms from the universal set of all the possible min-terms [m0 m1 m2 …. mN] of Boolean function of n variables, where, 0 < N < 2n-1. The resulting algorithm is in concise form and trivial to implement. Furthermore, the developed algorithm is equipped with added attributes of optimizing of time and space while executed.

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Simulation Of A Multi-Carrier System In A Non-Linear Flat Fading Channel, Samah A.B. Mustafa Apr 2025

Simulation Of A Multi-Carrier System In A Non-Linear Flat Fading Channel, Samah A.B. Mustafa

The Journal of Engineering Research

This paper is on multi-carrier wireless communication system, focusing on the physical layer in such modulation system. Multi-Carrier MC system has received much attention in modern communication technology and is finding attractive applications. The paper introduces and discusses the discrete cosine transform DCT-based MC. Similarities and differences with respect to the Fourier transform-based system are pointed out. It was found that a reduction up to 5dB in peak power can be gained over the conventional system. Also, the simulation over flat fading channel depicted that QAM signaling in MC scheme based on DCT performed better than that in FFT-based scheme, …

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Structural System Identification In The Time Domain Using Evolutionary And Behaviorally Inspired Algorithms And Their Hybrids, S. Sandesh, Abhishek Kumar Sahu, K. Shankar Apr 2025

Structural System Identification In The Time Domain Using Evolutionary And Behaviorally Inspired Algorithms And Their Hybrids, S. Sandesh, Abhishek Kumar Sahu, K. Shankar

The Journal of Engineering Research

In this study, parametric identification of structural properties such as stiffness and damping is carried out using acceleration responses in the time domain. The process consists of minimizing the difference between the experimentally measured and theoretically predicted acceleration responses. The unknown parameters of certain numerical models, viz., a ten degree of freedom lumped mass system, a nine member truss and a non-uniform simply supported beam are thus identified. Evolutionary and behaviorally inspired optimization algorithms are used for minimization operations. The performance of their hybrid combinations is also investigated. Genetic Algorithm (GA) is a well known evolutionary algorithm used in system …

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Selectivity And Activity Of Iron Molybdate Catalysts In Oxidation Of Methanol, Khalid Khazzal Hummadi, Karim H. Hassan, Phillip C.H. Mitchell Apr 2025

Selectivity And Activity Of Iron Molybdate Catalysts In Oxidation Of Methanol, Khalid Khazzal Hummadi, Karim H. Hassan, Phillip C.H. Mitchell

The Journal of Engineering Research

The selectivity and activity of iron molybdate catalysts prepared by different methods are compared with those of a commercial catalyst in the oxidation of methanol to formaldehyde in a continuous tubular bed reactor at 200-350 oC (473-623 oK), 10 atm (1013 kPa), with a methanol-oxygen mixture fixed at 5.5% by volume methanol: air ratio. The iron(III) molybdate catalyst prepared by co-precipitation and filtration had a selectivity towards formaldehyde in methanol oxidation comparable with a commercial catalyst; maximum selectivity (82.3%) was obtained at 573oK when the conversion was 59.7%. Catalysts prepared by reacting iron (III) and molybdate by kneading or precipitation …

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Extreme Gravity Waves In The Arabian Gulf, S. Neelamani, K. Al-Salem, K. Rakha Apr 2025

Extreme Gravity Waves In The Arabian Gulf, S. Neelamani, K. Al-Salem, K. Rakha

The Journal of Engineering Research

The extreme significant wave heights and the corresponding mean wave periods were predicted for return periods of 12, 25, 50, 100 and 200 years for 38 different locations in the territorial and offshore locations of countries surrounding the Arabian Gulf. The input wave data for the study is hindcast waves obtained using a WAM model for a total period of 12 years, (1993 to 2004). The peak over threshold method (with 1.0 m as threshold value), is used for selecting the data for the extreme wave analysis. In general, a Weibull distribution is found to fit the data well compared …

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Integration Of Fbg Strain Sensors In Wdm Networks, Effects On Quality Factor, Ali Al-Lawati, Hadj Bourdoucen Apr 2025

Integration Of Fbg Strain Sensors In Wdm Networks, Effects On Quality Factor, Ali Al-Lawati, Hadj Bourdoucen

The Journal of Engineering Research

A study of the effect of integrating an FBG sensor in a four wavelength WDM communications system operating at 1550 nm is presented. The simulations considered focus on the mutual effects of both the sensing and the communications systems. The effect of power levels of the interrogating optical source on the performance of the two systems is also investigated under excitation levels of up to 10 dBm. The network layout used in the simulations is based on an actual optical link in Oman having a variety of spans. The results obtained at data rates of 2.5 and 10 Gbps with …

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High-Performance Bicmos Transimpedance Amplifiers For Fiber-Optic Receivers, F. Touati, M. Loulou Apr 2025

High-Performance Bicmos Transimpedance Amplifiers For Fiber-Optic Receivers, F. Touati, M. Loulou

The Journal of Engineering Research

High gain, wide bandwidth, low noise, and low-power transimpedance amplifiers based on new BiCMOS common- base topologies have been designed for fiber-optic receivers. In particular a design approach, hereafter called "A more- FET approach", added a new dimension to effectively optimize performance tradeoffs inherent in such circuits. Using conventional silicon 0.8 μm process parameters, simulated performance features of a total-FET transimpedance amplifier operating at 7.2 GHz, which is close to the technology fT of 12 GHz, are presented. The results are superior to those of similar recent designs and comparable to IC designs using GaAs technology. A detailed …

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Performance Of Tetra And Gsm\Gprs As A Platform For Broadband Internet And Multimedia Evolution, M. I. Dababneh, E. S. Al-Khawaldeh Apr 2025

Performance Of Tetra And Gsm\Gprs As A Platform For Broadband Internet And Multimedia Evolution, M. I. Dababneh, E. S. Al-Khawaldeh

The Journal of Engineering Research

In this paper, a novel approach for the comparison between TETRA system and other contenders is presented showing the relative potentials, thence applications and possible new services. TETRA Voice plus Data (V+D) and GPRSbased- GSM performance are also compared for defined multimedia transmission to revise the capability of bothsystems to afford multimedia applications to large number of subscribers with the shortest time possible while maintaining the optimal channel utilization. Performance measurements for data transmission illustrate that TETRA exhibits faster time response for connection setup time than the GPRS\GSM applications can provide. Simulation results also confirm that TETRA can support larger …

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Heat Transfer Enhancement In A Ribbed Duct, J.M. Jalil, T.K. Murtadha, H.M. Kadom Apr 2025

Heat Transfer Enhancement In A Ribbed Duct, J.M. Jalil, T.K. Murtadha, H.M. Kadom

The Journal of Engineering Research

The rib enhancement of heat transfer in a duct is studied numerically and experimentally, where hot air passes through a duct (0.04 x 0.16 x 1.15 m3) with different rib arrangement. The arranments are lower 12-rib arrangement; upper 12 rib arrangement and 24 rib staggered arrangement. The staggered arrangement gives better performance than the others. Also, the angle of attack was studied for lower arrangement, three different values were tested (45°, 60° and 90°). Angle of 60° gives better performance. Numerically, the three-dimension continuity, Navier-Stokes and energy by finite volume method of flow of air through (0.04 x 0.16 x …

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High-Temperature Electronics: Status And Future Prospects In The 21st Century, F. Touati, F. Mnif, A. Lawati Apr 2025

High-Temperature Electronics: Status And Future Prospects In The 21st Century, F. Touati, F. Mnif, A. Lawati

The Journal of Engineering Research

This paper reviews the state of current electronics and states the drive toward high-temperature electronics. The problems specific to high-temperature effects on conventional electronics and prospects of alternative technologies like silicon-on-insulator, silicon carbide, and diamond are discussed. Improving petroleum recovery from oil wells with hightemperature coverage of downhole electronics, making combustion processes more efficient utilizing embedded electronics, programs for More Electric Aircraft and Vehicles necessitating distributed control systems, and environmental protection issues stress the need to use and develop high-temperature electronics. This makes high-temperature electronics a key-enabling technology in the 21st century. Actual applications using high-temperature electronics are discussed in …

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Generalized Model For Spectral Efficiency Of Cellular Systems, A.M. Abbosh Apr 2025

Generalized Model For Spectral Efficiency Of Cellular Systems, A.M. Abbosh

The Journal of Engineering Research

A general mathematical model was used to study the spectral efficiency of cellular systems. The model took into consideration effects of first and second tier interference. The random distribution of users across the whole area covered by the cellular system as well as the shadowing and multipath effects were taken into account. The influence of sectorization on value of the spectral efficiency was also studied. The model investigated the effects of the cell radius and cluster size on the spectral efficiency. The influence of different propagation conditions on the spectral efficiency was also considered. Results of simulation showed that an …

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Vector Directional Distance Rational Hybrid Filters For Color Image Restoration, L. Khriji Apr 2025

Vector Directional Distance Rational Hybrid Filters For Color Image Restoration, L. Khriji

The Journal of Engineering Research

A new class of nonlinear filters, called vector-directional distance rational hybrid filters (VDDRHF) for multispectral image processing, is introduced and applied to color image-filtering problems. These filters are based on rational functions (RF). The VDDRHF filter is a two-stage filter, which exploits the features of the vector directional distance filter (VDDF), the center weighted vector directional distance filter (CWVDDF) and those of the rational operator. The filter output is a result of vector rational function (VRF) operating on the output of three sub-functions. Two vector directional distance (VDDF) filters and one center weighted vector directional distance filter (CWVDDF) are proposed …

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Takagi-Sugeno Neuro-Fuzzy Modeling Of A Multivariable Nonlinear Antenna System, E. A. Al-Gallaf Apr 2025

Takagi-Sugeno Neuro-Fuzzy Modeling Of A Multivariable Nonlinear Antenna System, E. A. Al-Gallaf

The Journal of Engineering Research

This article investigates the use of a clustered based neuro-fuzzy system to nonlinear dynamic system modeling. It is focused on the modeling via Takagi-Sugeno (T-S) modeling procedure and the employment of fuzzy clustering to generate suitable initial membership functions. The T-S fuzzy modeling has been applied to model a nonlinear antenna dynamic system with two coupled inputs and outputs. Compared to other well-known approximation techniques such as artificial neural networks, the employed neuro-fuzzy system has provided a more transparent representation of the nonlinear antenna system under study, mainly due to the possible linguistic interpretation in the form of rules. Created …

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Using Mobile Computing And Information Technology In Civil Engineering Construction Projects, M.N. Jadid, M.M. Idress Apr 2025

Using Mobile Computing And Information Technology In Civil Engineering Construction Projects, M.N. Jadid, M.M. Idress

The Journal of Engineering Research

Mobile computing technology has an enormous potential in civil engineering, mainly in the field of construction management. This paper presents an approach by using mobile computing in a civil engineering construction project, exploring how information can be exchanged at a construction site, and how billing of quantities (BOQ), drawings and specifications are shared for the benefit of the project. One of the major obstacles in using information technology (IT) when applied to civil engineering is due to the dynamic changes in the construction activities and the diversity of construction methods as compared to other industries. This has proved to be …

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A Multi-Step Approach For Scheduling Tasks With Synchronization On Clusters Of Computers, B.R. Arafeh Apr 2025

A Multi-Step Approach For Scheduling Tasks With Synchronization On Clusters Of Computers, B.R. Arafeh

The Journal of Engineering Research

In this work, a two-step approach is adopted for scheduling tasks with synchronous inter-task communication. To that end, an efficient algorithm, called GLB-Synch, is introduced for mapping clusters and ordering tasks on processors. The algorithm used the information obtained during the clustering step for selecting a cluster to be mapped on the least loaded processor. A performance study has been conducted on the GLB-Synch algorithm by simulation. A multi-step scheduling setup has been performed based on a previously developed algorithm for clustering DAGs with synchronous communication, called NLC-SynchCom, and using synthesized DAGs. We have shown by analysis and experimentation that …

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Pavement Stripping In Saudi Arabia: Prediction And Prevention, H.I. Al-Abdul Wahhab, I.M. Asi, S.A. Ali, S. Al-Swailmi, A. Al-Nour Apr 2025

Pavement Stripping In Saudi Arabia: Prediction And Prevention, H.I. Al-Abdul Wahhab, I.M. Asi, S.A. Ali, S. Al-Swailmi, A. Al-Nour

The Journal of Engineering Research

Pavement weathering or stripping is a major distress in highway networks in arid regions. Using the Saudi Arabian road network as a case study area, seventeen road test sections were selected, out of which eight were stripped and nine were non-stripped. Aggregates from quarries used to build these sections were also collected and subjected to detailed physical and chemical tests to evaluate the ability of these tests to distinguish between stripped and non-stripped sections. The modified Lottman test was used to distinguish between compacted mixes. In addition, the Swedish Rolling Bottle test, was also found to be effective in being …

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Hearing Islam: The Sounds Of A Global Religious Tradition, Bertie Kibreah Apr 2025

Hearing Islam: The Sounds Of A Global Religious Tradition, Bertie Kibreah

Yale Journal of Music & Religion

A book review is presented for Hearing Islam: The Sounds of a Global Religious Tradition, authored by Lauren E. Osborne, by Bertie Kibreah.

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Thomas Pereira’S 'Lülü Zuanyao' 律呂纂要 (Ca. 1685): A Jesuit Music Theory Textbook For The Chinese Emperor, Qingfan Jiang Apr 2025

Thomas Pereira’S 'Lülü Zuanyao' 律呂纂要 (Ca. 1685): A Jesuit Music Theory Textbook For The Chinese Emperor, Qingfan Jiang

Yale Journal of Music & Religion

Thomas Pereira (1646–1708), a Portuguese Jesuit missionary, arrived in Beijing in 1672 and was appointed by the Kangxi Emperor (1654–1722) as his music tutor. For the emperor's music lessons, Pereira authored Lülü Zuanyao 律呂纂要 [Elements of Music] (ca. 1685), the first known Western music theory treatise written in Chinese. My translation includes the first half of Zuanyao that focuses on Western music notation, solmization, and the hexachordal system. As a product of the global circulation of musical knowledge in the early modern period, Zuanyao is significant in three ways. First, it illustrates the direct influence of the music education Pereira …

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Commemorating August Thirteenth: Music And Theology In Eighteenth-Century Moravian Communities, Ryan M. Malone Apr 2025

Commemorating August Thirteenth: Music And Theology In Eighteenth-Century Moravian Communities, Ryan M. Malone

Yale Journal of Music & Religion

One of the most important memorial days in the Moravian liturgical calendar is August Thirteenth, a commemoration of the communal spiritual awakening that eighteenth-century Moravians experienced on the Saxon estate of Count Nikolaus Ludwig von Zinzendorf (1700–1760). While the Moravian church has celebrated this storied event for centuries, complete with music-rich religious services, only a few original compositions were crafted specifically for these services. In light of the importance of August Thirteenth, and given of the abundance of musical works that eighteenth-century Moravian composers wrote for other memorial days and religious holidays, this article employs musicological and theological perspectives to …

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"Everyone Watches Womens Sports", Promoting Inclusion And Raising Awareness Through Social Media, Katelyn Bytheway Apr 2025

"Everyone Watches Womens Sports", Promoting Inclusion And Raising Awareness Through Social Media, Katelyn Bytheway

Student Research Symposium

The "Everyone Watches Women's Sports" campaign is an initiative by TOGETHXER, a media and commerce company founded by athletes Alex Morgan, Chloe Kim, Simone Manuel, and Sue Bird. Launched in December 2023, the campaign aims to elevate the visibility and support of women's sports.

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The Change Of Life Happens: How To Overcome Challenges In Order To Succeed., Robin Cruz Apr 2025

The Change Of Life Happens: How To Overcome Challenges In Order To Succeed., Robin Cruz

Student Research Symposium

The movies that are part of these exhibit tell about the different situations of students and how they can achieve their dreams. It also shows how to overcome the obstacle that they are facing in the different settings.

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