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Some aspects affecting the response of RC compartment structures subjected to internal blast loads

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 135-148页

作者： Osman m.O.Ramadan m.Galal El Sherbiny ahmed m.Khalil Faculty of Engineering Cairo UniversityCairo 12411Egypt Higher Technological Institute(HTI)at 10th of Ramadan City Sharqia 13658Egypt Structural Engineering and Construction management Department Faculty of Engineering&TechnologyFutureUniversity in Egypt-FUECairo 16383Egypt

Protective compartments are typically used to protect some specific structures from internal explosions,such as industrial buildings that contain devices that may explode in certain *** research investigates how the response of reinforced concrete(RC)compartment structures subjected to internal blast loads are affected by the following aspects:introduction of material nonlinearity in the analysis,reinforcement ratio,and aspect ratio of the *** achieve this goal,a calibrated and sophisticated FE numerical model is introduced,and a parametric study for the intended aspects is carried out.A discussion of the results and conclusions are offered,which show the role of each aspect in the dynamic performance of the compartment *** main conclusions are as follows:introduction of material nonlinearity in this type of analysis and for these structures is very important and significant in obtaining accurate outputs that are similar to actual behavior;the reinforcement ratio has a significant effect on the response and its effect varies depending on the thickness of the compartment;in general,increasing the reinforcement ratio enhances the behavior and reduces the stresses in the compartment;and the aspect ratio of the compartment does not show a clear pattern on the response of such structures under internal blast loads.

关键词： blast loads protective structures nonlinear analysis explicit dynamic analysis

Evaluating the potential of surface-modified silica nanoparticles using internal olefin sulfonate for enhanced oil recovery

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Petroleum Science 2020年第3期17卷 722-733页

作者： Afaque ahmed Ismail mohd Saaid Abdelazim Abbas ahmed Rashidah m.Pilus mirza Khurram Baig Petroleum Engineering Department Universiti Teknologi PETRONASSeri IskandarMalaysia Center of Research in Enhanced Oil Recovery Universiti Teknologi PETRONASSeri IskandarMalaysia Department of Physics University of OkaraOkaraPunjabPakistan

Recently,nanoparticles have proven to enhance oil recovery on the core-flood scale in challenging high-pressure high-temperature *** generally appear to improve oil production through wettability alteration and reduction in interfacial tension between oil and water ***,they are environmentally friendly and cost-effective enhanced oil recovery *** the rheological properties of nanoparticles is critical for field *** instability of nanoparticle dispersion due to aggregation is considered as an unfavorable phenomenon in nanofluid flooding while conducting an EOR *** this study,wettability behavior and rheological properties of surface-treated silica nanoparticles using internal olefins sulfonates(IOS20–24 and IOS19–23),anionic surfactants were *** modification effect on the stability of the colloidal solution in porous media and oil recovery was *** rheology of pure and surfacetreated silica nanoparticles was investigated using a HPHT *** and particle size distributions of pure and coated silica nanoparticles were studied using a field emission scanning electron microscope.A series of core-flood runs was conducted to evaluate the oil recovery *** coated silica nanoparticles were found to alter rheological properties and exhibited a shear-thinning behavior as the stability of the coated silica nanoparticles could be improved *** low shear rates,the viscosity slightly increases,and the opposite happens at higher shear ***,the surfacemodified silica nanoparticles were found to alter the wettability of the aqueous phase into strongly water-wet by changing the contact angle from 80°to 3°measured against glass slides representing sandstone ***–water IFT results showed that the surface treatment by surfactant lowered the oil–water IFT by 30%.Also,the viscosity of brine increased from 0.001 to 0.008 Pa s by introducing SiO2 nano

关键词： Silica nanoparticles Anionic surfactant Rheological properties of nano fluids Wettability alteration Enhanced oil recovery

Comparison of Ground Water Bacterial Cell Sizes from the Agricultural, Domestic and Industrial Areas of mysore District, Karnataka State, India

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应用与环境生物学报 2008年第4期14卷 503-509页

作者： Wadie ahmed mokbel Sadanand m Yamakanamardi Aquatic microbial Ecology Research Laboratory Department of Studies in Zoology University of Mysore Manasagangotri Mysore-570006 Karnataka State India

A two-year study on temporal variations in the ground water heterotrophic bacterial cell sizes of free living bacteria (FLB) and particle bound bacteria (PBB) from the agricultural, domestic and industrial areas was carried out from February 2005 to January 2007. The overall mean cell length of FLB and PBB was similar in all the ground water studied. However, the season wise grouped data revealed significant seasonal changes in cell length of FLB and PBB, as smaller bacteria were noticed during rainy season in the ground water in agricultural area in both the years, and only in the second year of study in domestic and industrial areas. Generally, it was noticed that there were summer maximum and rainy minimum values of the cell length of PBB in the ground water in agricultural, domestic and industrial areas in the second year of study. The Pearson's correlations showed the presence of 8 (in agricultural area), 5 (in domestic) and 3 (in industrial) significant correlations with environmental (Physico-chemical) parameters, respectively. The regression analysis revealed that as much as 12% of variation in the mean length of FLB was due to NO3 (+) in agricultural area and 9% due to total solids (+) in domestic area. However, the 8 % variation in bacterial cell size of FLB was due to mg (+) in industrial area. Whereas, 13 % variation in mean length of PBB was due to SO4 (+) in agricultural area and 10% due to total anions of strong acid (TASA) (+) in domestic area. Furthermore, 10 % of variation was due to PO4 (+) in industrial area. Thus, the statistical analysis revealed that several environmental variables were potentially responsible for some of the temporal variations in aquatic heterotrophic bacterial cell size, suggesting probably the stressed environment in these ecosystems.

关键词：地下水微生物细胞环境保护

An Adaptive Real-Time Third Order Sliding mode Control for NonlinearSystems

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Computers, materials & Continua 2022年第9期72卷 5629-5641页

作者： ahmed m.Elmogy Amany Sarhan Wael m.Elawady Computer Engineering Department Prince Sattam Bin Abdelaziz UniversityAlkharj24567KSA Department of Computers and Control Engineering Tanta UniversityTanta13457Egypt

As most real world systems are significantly nonlinear in nature,developing robust controllers have attracted many researchers for *** controllers are the controllers that are able to cope with the inherent uncertainties of the nonlinear *** control methods have been developed for this *** mode control(SmC)is one of the most commonly used methods in developing robust *** paper presents a higher order SmC(HOSmC)approach to mitigate the chattering problem of the traditional SmC *** developed approach combines a third order SmC with an adaptive PID(proportional,integral,derivative)sliding surface to overcome the drawbacks of using PID controller ***,the presented approach is capable of adaptively tuning the controller parameters online to best fit the real time *** Lyapunov theory is used to validate the stability of the presented approach and its feasibility is tested through a comparison with other conventional SmC approaches.

关键词： SmC uncertain nonlinear systems PID lyapunov theory

Optimal FOPID Controllers for LFC Including Renewables by Bald Eagle Optimizer

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Computers, materials & Continua 2022年第12期73卷 5525-5541页

作者： ahmed m.Agwa mohamed Abdeen Shaaban m.Shaaban Department of Electrical Engineering College of EngineeringNorthern Border UniversityArar1321Saudi Arabia Electrical Engineering Department Faculty of EngineeringAl-Azhar UniversityCairo11651Egypt Department of Engineering Basic Science Faculty of EngineeringMenoufia UniversityShebin El-Kom32511Egypt

In this study,a bald eagle optimizer(BEO)is used to get optimal parameters of the fractional-order proportional-integral-derivative(FOPID)controller for load frequency control(LFC).SinceBEOtakes only a very short time in finding the optimal solution,it is selected for designing the FOPID controller that improves the system stability and maintains the frequency within a satisfactory range at different *** and demonstrations are carried out using *** performance of the BEOFOPID controller is evaluated using a two-zone interlinked power system at different loads and under uncertainty of wind and solar *** robustness of the BEO-FOPID controller is examined by testing its performance under varying system time *** results obtained by the BEOFOPID controller are compared with those obtained by BEO-PID and PID controllers based on recent metaheuristics optimization algorithms,namely the sine-cosine approach,Jaya approach,grey wolf optimizer,genetic algorithm,bacteria foraging optimizer,and equilibrium optimization *** results confirm that the BEO-FOPID controller obtains the finest result,with the lowest frequency *** results also confirm that the BEOFOPID controller is stable and robust at different loads,under varying system time constants,and under uncertainty of wind and solar energies.

关键词： Fractional order PID control load frequency control renewable energy bald eagle optimizer

Implications of Onshore Development on Global Software Engineering

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Computers, materials & Continua 2023年第2期74卷 3029-3044页

作者： Abdulrahman m.Qahtani ahmed S.Ghiduk College of Computers and Information Technology Taif UniversityP.O.Box 11099Taif21944Saudi Arabia Department of mathematics and Computer Science Faculty of ScienceBeni-Suef UniversityBeni-Suef62521Egypt

Recently software industry has paid significant attention to customizing software products across distributed *** the requirements of multiple clients across distributed borders is a crucial challenge for the software customization *** decision-making and local development at the client site are considered methods for reducing difficulties in communicating the requirements of multiple clients across distributed *** paper introduces a new model called the onshore development model(ODm)for accomplishing the customization requests in the distributed development process of *** model presents a scenario for enhancing the onsite development of specific requirements to reduce delays andmisunderstandings between the clients and the team *** model depends on moving the development process to the client’s *** empirical studies were conducted to evaluate the proposed model to measure its productivity,time performance,and cost *** proposed model has been compared with two other models:the basic model(Bm),which allocates the decision-making process and the development process for teams at the vendor’s location,and the local decision-making model(LDec),which assigns the decision-making process for team at the client’s *** results of the empirical studies showed significant outperforming of the proposed model over the basic model and local decision-making model in productivity,time performance,and cost *** productivity of the proposed model improved by 39%and 10%more than the basic model and the local decision-making model,*** addition,the time performance of the proposed model became faster by 49%and 20.8%than the basic model and the local decision-making model,***,it reduced the total cost of the development process by 31%in terms of the salaries of all persons involved in requirements collecting,decision-making,and development.

关键词： Distributed development local development software customization

Neuro-Based Higher Order Sliding mode Control for Perturbed Nonlinear Systems

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Intelligent Automation & Soft Computing 2023年第4期36卷 385-400页

作者： ahmed m.Elmogy Wael m.Elawady Computer Engineering Department Prince Sattam Bin Abdelaziz UniversityAlkharj24567KSA Department of Computers and Control Engineering Tanta UniversityTanta13457Egypt

One of the great concerns when tackling nonlinear systems is how to design a robust controller that is able to deal with *** researchers have been working on developing such type of *** of the most efﬁ-cient techniques employed to develop such controllers is sliding mode control(SmC).However,the low order SmC suffers from chattering problem which harm the actuators of the control system and thus unsuitable to be used in many practical *** this paper,the drawbacks of low order traditional sliding mode control(FOTSmC)are resolved by presenting a novel adaptive radial basis function neural network–based generalized rth order sliding mode control strategy for nth order uncertain nonlinear *** proposed solution adopts neural networks for their excellent capability in function approximation and thus used to approximate the nonlinearities and uncertainties for systems under *** approximation errors are completely considered in the developed *** proposed approach can be used with any order of sliding mode and thus can be generally used with various types of *** global sta-bility of the proposed control approach is proved through Lyapunov stability *** proposed approach is validated and assessed through simulations on the nonlinear inverted pendulum system with severe modeling *** simulations results show that the proposed approach provide superior perfor-mance compared with other approaches in the literature.

关键词： SmC nonlinear systems PID Lyapunov stability radial basis function neural networks

Numerical Study of mixed Convective Peristaltic Flow through Vertical Tube with Heat Generation for moderate Reynolds and Wave Numbers

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Communications in Theoretical Physics 2018年第4期69卷 449-460页

作者： Tariq Javed B.ahmed m.Sajid Department of mathematics and Statistics International Islamic University

The current study focuses on the numerical investigation of the mixed convective peristaltic mechanism through a vertical tube for non-zero Reynolds and wave number. In the set of constitutional equations, energy equation contains the term representing heat generation parameter. The problem is formulated by dropping the assumption of lubrication theory that turns the model mathematically into a system of the nonlinear partial differential equations. The results of the long wavelength in a creeping flow are deduced from the present analysis. Thus, the current study explores the neglected features of peristaltic heat flow in the mixed convective model by considering moderate values of Reynolds and wave numbers. The finite element based on Galerkin's weighted residual scheme is applied to solve the governing equations. The computed solution is presented in the form of contours of streamlines and isothermal lines, velocity and temperature profiles for variation of different involved parameters. The investigation shows that the strength of circulation for stream function increases by increasing the wave number and Reynolds number. Symmetric isotherms are reported for small values of time-mean flow. Linear behavior of pressure is noticed by vanishing inertial forces while the increase in pressure is observed by amplifying the Reynolds number.

关键词： mixed convection peristaltic flow moderate Reynolds number finite element method

Average Convergence for Directed&Undirected Graphs in Distributed Systems

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Computer Systems Science & Engineering 2021年第6期37卷 399-413页

作者： Ali mustafa m Najam ul Islam Salman ahmed Bahria University Islamabad44000Pakistan Comsats University Islamabad Attock campus43600Pakistan University of Engineering&Technology Peshawar25000Pakistan

Consensus control of multi-agent systems is an innovative paradigm for the development of intelligent distributed *** has fascinated numerous scientific groups for their promising applications as they have the freedom to achieve their local and global goals and make their own *** communication topologies based on graph and matrix theory are widely used in a various real-time applications ranging from software agents to ***,while sustaining the significance of both directed and undirected graphs,this research emphases on the demonstration of a distributed average consensus *** uses the harmonic mean in the domain of multi-agent systems with directed and undirected graphs under static topologies based on a control input *** proposed agreement protocol focuses on achieving a constant consensus on directional and undirected graphs using the exchange of information between neighbors to update their status values and to be able to calculate the total number of agents that contribute to the communication network at the same *** proposed method is implemented for the identical networks that are considered under the directional and non-directional communication *** different scenarios are simulated and it is concluded that the undirected approach has an advantage over directed graph communication in terms of processing time and the total number of iterations required to achieve *** same network parameters are introduced for both orientations of the communication *** addition,the results of the simulation and the calculation of various matrices are provided at the end to validate the effectiveness of the proposed algorithm to achieve consensus.

关键词： multi-agent systems average consensus distributed estimation directed graphs undirected graphs agent counting