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Clean Energy 2024年第2期8卷 177-188页

作者： Mohammed J.K.Bashir Senadjki Abdelhak wael a.salah Mai Abuhelwa School of Engineering&Technology Central Queensland University120 Spencer St.MelbourneQLD 3000Australia Faculty of Business and Finance Universiti Tunku Abdul RahmanKamparPerakMalaysia Department of Electrical Engineering College of Engineering and TechnologyPalestine Technical University-KadooriePO Box 7Yafa StreetTulkarmPalestine Department of Electrical Engineering and Computer Science University of MissouriColumbiaMO 65211USA

The study focuses on the transition from conventional energy sources to sustainable renewable energy(RE)in Palestine,particularly in the West Bank and Gaza *** research aims to understand the relationship between key factors and residents’willingness to invest in the RE sector,with a specific focus on the impact of *** the unified theory of acceptance and use of technology,the study analyzes data from 400 residents through a questionnaire and employs ordinary least-squares regression analysis with Eviews *** key findings indicate that residents’inclination to invest in RE is significantly influenced by factors such as resource availability,knowledge level and power ***,the study suggests that educated residents are more likely to invest in RE when factors such as knowledge,effort expectation,enabling conditions and resource availability are relatively *** conclusion emphasizes the importance of policymakers’allocating sufficient funds to research and development to promote technological innovation in RE sources,thereby enhancing the population’s energy efficiency.

关键词： renewable energy technology energy security public perceptions sustainable development

Robust Hybrid Control for Ballistic Missile Longitudinal Autopilot

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Chinese Journal of Aeronautics 2011年第6期24卷 777-788页

作者： wael Mohsen Ahmeda wael Mohsen Ahmed QUAN Quan Department of Automatic Control School of Automation Science and Electrical Engineering Beihang University Beijing 100191 China State Key Laboratory of Virtual Reality Technology and Systems Beihang University Beijing 100191 China

This paper investigates the boost phase＇s longitudinal autopilot of a ballistic missile equipped with thrust vector control. The existing longitudinal autopilot employs time-invariant passive resistor-inductor-capacitor （RLC） network compensator as a control strategy, which does not take into account the time-varying missile dynamics. This may cause the closed-loop system instability in the presence of large disturbance and dynamics uncertainty. Therefore, the existing controller should be redesigned to achieve more stable vehicle response. In this paper, based on gain-scheduling adaptive control strategy, two different types of optimal controllers are proposed. The first controller is gain-scheduled optimal tuning-proportional-integral-derivative （PID） with actuator constraints, which supplies better response but requires a priori knowledge of the system dynamics. Moreover, the controller has oscillatory response in the presence of dynamic uncertainty. Taking this into account, gain-scheduled optimal linear quadratic （LQ） in conjunction with optimal tuning-compensator offers the greatest scope for controller improvement in the presence of dynamic uncertainty and large disturbance. The latter controller is tested through various scenarios for the validated nonlinear dynamic flight model of the real ballistic missile system with autopilot exposed to external disturbances.

关键词： ballistic missiles attitude control gain-scheduling optimal tuning-control LQ optimal regulators

CONCENTRATION OF SOLUTIONS FOR THE MEAN CURVATURE PROBLEM

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Acta Mathematica Scientia 2013年第3期33卷 631-642页

作者： wael ABDELHEDI Department of Mathematics Faculty of Sciences of Sfax University of Sfax

We consider the problem of conformal metrics equivalent to the Euclidean metric, with zero scalar curvature and prescribed mean curvature on the boundary of the ball Bn, n ≥ 4. By variational methods, we prove the existence of two peak solutions that concentrate around a strict local maximum points of the mean curvature under certain conditions.

关键词： Boundary mean curvature critical Sobolev exponent critical points at infinity

Serviceability analysis of deep underground openings driven in jointed-rock

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International Journal of Mining Science and Technology 2017年第6期27卷 1019-1024页

作者： Abdellah wael R. Mining and Metallurgical Engineering Department Faculty of Engineering University of Assiut Assiut 71515 Egypt

The performance of underground excavations is inevitably influenced by rock mass characteristics, presence of joints and their geometrical properties, depth below surface and state of in-situ stress field. The objective of this paper is to investigate the behaviour of deep underground tunnel opening existed between two bedding planes, Such planes weaken the strength of rock mass and may cause rock slippage/rotation along them. Therefore, the state of stress-displacement, after tunnel opening has been introduced, is examined using two-dimensional elasto-plastic finite-elements code, RS^(2D). The results indicate that, there is significant drop in the normal stress along joints over tunnel opening; slip occurs due to reversal in the direction of shear stress(e.g., inward shear displacement is produced) and there is discontinuity in the strength contours of rock surrounding tunnel after they have been intersected by bedding planes.

关键词： State of stress-displacement Bedding planes Tunnel performance Depth of failure zones Stability analysis

Modeling bending behavior of shape memory alloy wire-reinforced composites: Semi-analytical model and finite element analysis

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Chinese Journal of Aeronautics 2021年第8期34卷 176-191页

作者： Nguyen Van VIET wael ZAKI Department of Mechanical Engineering Khalifa University of Science and TechnologyAbu DhabiUnited Arab Emirates

In this study,we propose a novel and simple exact semi-analytical model for superelastic Shape Memory Alloy(SMA)wire reinforced composites subjected to bending *** order to study the mechanical response of the composite during loading/unloading,a Representative Volume Element(RVE)is extracted to examine the bending response of the *** moment–curvature,and shear force-shear strain relations are derived based on a 3-Dimensional(3 D)thermomechanical SMA model and Timoshenko beam *** composite Simpson’s rule is adopted to numerically solve the exact analytical moment–curvature and shear force-shear strain *** including the moment–curvature response,axial stress distribution along the vertical and longitudinal directions,martensite volume fraction,and the tip deflection are reported and validated against 3 D finite element *** influence of temperature,martensite volume fraction distribution,and matrix stiffness on the mechanical performance of the composite is also *** particular,the composite is found to behave superelastically under certain conditions of temperature,SMA volume fraction,and elastic stiffness of the *** behavior is advantageous in applications requiring large recoverable strains or high energy dissipation density.

关键词： Bending Finite element analysis Modelling Phase transformation Shape memory alloy reinforced composite Superelasticity

Transition of children with inflammatory bowel disease: Big task,little evidence

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World Journal of Gastroenterology 2009年第30期15卷 3744-3747页

作者： wael El-Matary Division of Pediatric Gastroenterology Hepatology and NutritionStollery Children's HospitalFaculty of MedicineUniversity of AlbertaEdmontonAlberta T6G 2J3Canada

Children with chronic long-term disorders need to move to the adult practice at some point in their life. Establishing a smooth and efficient transition process is a complicated task. Transition of medical care to adult practice is def ined as the purposeful planned movement of adolescents and young adults with chronic physical and medical conditions from child-centered to adultoriented health care systems. This step is of the utmost importance for several reasons. There is an obvious deficiency of research in this area especially when it comes to pediatric inflammatory bowel disease (IBD). There is a considerable difference in individual practice among different centers. Also, age of transition varies among different countries and sometimes, even within the same country, transition age may vary among different provinces and districts! Interestingly, local politics and many factors other than children’s welfare often play a role in deciding the age that older children move to adult practice at. This review discusses transition of children with IBD in view of the available evidence.

关键词： Transition Inflammatory bowel disease Adolescent

Smartphones and traffic signals:A quantitative assessment for phone usage behavior on performance of signalized intersections

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Journal of Traffic and Transportation Engineering(English Edition) 2023年第4期10卷 611-632页

作者： wael ElDessouki Abdulrahman AlManeea Department of Transportation and Traffic Engineering Imam Abdulrahman Bin Faisal UniversityDammam 31441Kingdom of Saudi Arabia

Modern smartphones differ vastly from classic cellphones with enormous capabilities,changing cellphones from making phone calls and short messages to pocket-sized computers with full internet *** downside of modern phone evolution is changing drivers’behavior and phone usage *** researchers have investigated the safety implications of phone usage while driving on accidents ***,the effect of phone usage on the performance of traffic facilities did not receive equal ***,this research aims to study the impact of smartphone usage on traffic signal *** parameters considered in the study were drivers’activity while waiting at the signal,startup lost time,and saturation flow *** study team covered 25 intersections in the study area,observed the activities of over 6800 drivers while waiting at the signal,and recorded their corresponding discharge *** study team then supplemented field data with a behavioral survey questionnaire for drivers living in the study area to interpret field ***,the collected data were processed and analyzed,resulting in mathematical models for the relationship between the reduction in saturation flow rate and the red time *** team found two primary *** study’s first finding was that the traditional concept for estimating startup lost time adopted by the highway capacity manual(HCM)appears *** field results revealed that the lost times caused by other distracted drivers upstream in the queue were comparable to the estimated startup lost time following the HCM method for estimating startup lost *** second finding was that the reduction in saturation flow rate at the traffic signal is an exponential function of the red time interval,reducing the overall capacity for the intersection and increasing the average ***,the authors suggest mitigating the problem and making recommendations for future research.

关键词： Signals Smartphone Saturation Flow Discharge Headway

Approximate Solution of the Kuramoto-Shivashinsky Equation on an Unbounded Domain

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Chinese Annals of Mathematics,Series B 2018年第1期39卷 145-162页

作者： wael W.MOHAMMED Department of Mathematics Faculty of ScienceMansoura University Department of Mathematics Faculty of ScienceHail University

The main goal of this paper is to approximate the Kuramoto-Shivashinsky(K-S for short) equation on an unbounded domain near a change of bifurcation,where a band of dominant pattern is changing *** leads to a slow modulation of the dominant *** we consider PDEs with quadratic nonlinearities and derive rigorously the modulation equation,which is called the Ginzburg-Landau(G-L for short) equation,for the amplitudes of the dominating modes.

关键词： Multi-scale analysis Modulation equation Kuramoto-Shivashinsky equation Ginzburg-Landau equation

An Exact Solution for Acoustic Simulation Based Transmission Loss Optimization of Double-Chamber Silencer

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Sound & Vibration 2020年第4期54卷 215-224页

作者： wael A.Altabey International Institute for Urban Systems Engineering(IIUSE) Southeast UniversityNanjing210096China Department of Mechanical Engineering Faculty of EngineeringAlexandria UniversityAlexandria21544Egypt

The optimization of the acoustic silencer volume is very important to develop it and to get high-performance,the importance of the silencer was appeared in industrial field to eliminate the noise of the duct by efficient and economical *** main goal of this research is to optimize the transmission loss(TL)by analytical method of the Double-Chamber Silencer(DCS),the TL has been selected as the main parameter in silencer because it does not based on the source or the termination *** we calculated the power transmission coefficient(PTC)and the TL of an acoustic silencer,then used the Lagrange method to optimize the silencer *** calculation of silencer data is obtained by solving the governing equations in commercial software Matlab®.A several calculations for different silencer length at many frequency ranges were performed ***,this research supports the efficient and rapid techniques for DCS optimal design under narrow *** results show that the acoustic TL is maximized at the desired frequency.

关键词： Acoustic silencer/filter double-chamber silencer transmission loss power transmission optimization

Reaching law based sliding mode control for a frame structure under seismic load

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Earthquake Engineering and Engineering Vibration 2021年第3期20卷 727-745页

作者： Ying Zhao Mohammad Noori wael A.Altabey International Institute for Urban Systems Engineering Southeast UniversityNanjing 210096China Department of Mechanical Engineering California Polytechnic State UniversitySan Luis ObispoCA 93405USA Department of Mechanical Engineering Faculty of EngineeringAlexandria UniversityAlexandria 21544Egypt

Implementation of efficient vibration control schemes for seismically excited structures is becoming more and more important in recent *** this study,the influence of different control schemes on the dynamic performance of a frame structure excited by El Centro wave,with an emphasis on reaching law based control strategies,is *** law refers to the reachable problem and criteria for the sliding state of a control *** reaching laws are designed to present different sliding mode control strategies by incorporating a state space model that describes structural dynamic characteristics of a frame *** intact and damaged structures are studied by using the aforementioned control *** influence of different structural damage extents,control locations and reaching law based control methods are further *** results show that the structure can be well controlled using the sliding mode strategy when the induced structural damage extent does not exceed the standard percentage for considering the structure was damaged,which is 20%reduction in structure stiffness,as reported in the *** control effectiveness is more satisfactory if the control location is the same as the direction of external ***,to study the chattering phenomenon of the sliding mode control method,approximation and detail components extracted from the phase plots of the sliding mode control system are compared via wavelet transform at different *** results show that for the same type of control law,the system behaves with similar chattering phenomenon.

关键词： reaching law sliding mode control state-space model phase plot 2-D wavelet transform