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Efficient Numerical Scheme for the Solution of HIV Infection CD4^(+)T-Cells Using Haar Wavelet Technique

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Computer Modeling in Engineering & Sciences 2022年第5期131卷 639-653页

作者： Rohul amin Suayip Yuzbasi Shah Nazir Department of Mathematics University of PeshawarPeshawar25120Pakistan Department of Mathematics Faculty of ScienceAkdeniz UniversityAntalyaTr-07058Turkey Department of Computer Science University of SwabiSwabi23430Pakistan

In this paper,Haar collocation algorithmis developed for the solution of first-order ofHIV infection CD4^(+)T-Cells *** this technique,the derivative in the nonlinear model is approximated by utilizing Haar *** value of the unknown function is obtained by the process of *** estimation is also discussed,which aims to reduce the error of numerical *** numerical results show that the method is simply *** results are compared with Runge-Kutta technique,Bessel collocation technique,LADM-Pade and Galerkin technique available in the *** results show that the Haar technique is easy,precise and effective.

关键词： System of nonlinear differential equations HIV infection of CD4^(+)T-cells Broyden method Haar wavelet residual error estimation

Composite insulators and their aging: An overview

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Science China(Technological Sciences) 2007年第6期50卷 697-713页

作者： Muhammad amin Muhammad AKBAR Muhammad SALMAN University of Engineering and Technology

The aging (biological deterioration) is a major problem of composite insulators now-a-days. The main thing in aging is to predict how, when and with what speed it occurs and under what conditions it can lead to failure and what overall average expected life of a composite insulator is. For this a lot of researches have been done. This review summarizes the methods of artificial field testing (aging), natural testing, standards the developed for aging, techniques of analysis, results achieved until now about various parameters from various locations, handling guidelines and a conclusion on what is further needed.

关键词： polymeric insulators, aging, composite, SEM

Influence of Mold Preheating and Silicon Content on Microstructure and Casting Properties of Ductile Iron in Permanent Mold

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Journal of Iron and Steel Research International 2011年第3期18卷 34-39页

作者： Jafar Khalil-Allafi Behnam amin-Ahmadi Faculty of Materials Engineering Sahand University of Technology Department of Materials Science and Engineering Sharif University of Technology

The effects of the mold preheating and the silicon content of ductile iron on the percentage of carbides,graphite nodule counts and shrinkage volume were *** results showed that the percentage of carbides and the shrinkage volume decreased when the mold preheating *** ductile iron with the carbon equivalent of 4.45 % and the silicon content of 2.5% without any porosity defects was achieved when the mold preheating was 450 ℃.Increasing the silicon content in the range of 2.1%-3.3% led to the increase in graphite nodule count and graphite size and the decrease in percentage of *** is due to the increase in induced expansion pressure during the graphite formation with the increasing of silicon *** suitable condition for casting a sound product of ductile iron without the riser at the mold preheating temperature of 300 ℃ is the silicon content of 3.3% and carbon equivalent of 4.7%.

关键词： ductile iron permanent mold preheating temperature carbide shrinkage volume silicon content

Three-dimensional seismic face stability of shield tunnels inundrained clay

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Underground Space 2024年第2期15卷 26-43页

作者： Milad Davoodi Salvador Senent amin Keshavarz Rafael Jimenez Civil Engineering Department School of EngineeringPersian Gulf UniversityBushehr ***Iran Universidad Politecnica de Madrid C/Prof.Aranguren s/nMadrid 28040Spain

Tunnel face stability has received increasing research interest over the past few decades. However, computing time-efficient and safethree-dimensional solutions under seismic loading is still an unsolved problem, while case studies indicate that seismic loading can be onecritical destabilizing factor affecting tunnel stability. The primary objective of this work is to fill this gap in knowledge by providing compromisingand computationally efficient solutions, along with their respective lower and upper bounds, to compute face stability underseismic conditions. The analyses employ the finite element limit analysis method to evaluate the limit support pressure in undrained clay,considering horizontal pseudo-static seismic forces pointing outwards from the face. Moreover, the analyses employ both constant andlinearly increasing shear strengths with depth. The results are summarized as dimensionless stability charts and tables to facilitate theirinterpretation and future use for tunnel design. A new design equation has been developed to evaluate the stability of the tunnel faceconsidering the effect of seismic forces. Additionally, the effects of different parameters on the shape of the failure mechanism have beeninvestigated by analysing the distribution of shear dissipation.

关键词： Tunnel face stability Finite element limit analysis Undrained clay Seismic stability

A three-dimensional Moho depth model beneath the Yemeni highlands and rifted volcanic margins of the Red Sea and Gulf of Aden, Southwest Arabia

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China Geology 2023年第4期6卷 611-622页

作者： amin Noman Al Kadasi Department of Geology Faculty of Applied ScienceTaiz UniversityTaiz 04Yemen

Knowing Moho discontinuity undulation is fundamental to understanding mechanisms of lithosphereasthenosphere interaction, extensional tectonism and crustal deformation in volcanic passive margins such as the study area, which is located in the southwestern corner of the Arabian Peninsula bounded by the Red Sea and the Gulf of Aden. In this work, a 3D Moho depth model of the study area is constructed for the first time by inverting gravity data from the Earth Gravitational Model(EGM2008) using the ParkerOldenburg algorithm. This model indicates the shallow zone is situated at depths of 20 km to 24 km beneath coastal plains, whereas the deep zone is located below the plateau at depths of 30 km to 35 km and its deepest part coincides mainly with the Dhamar-Rada ’a Quaternary volcanic field. The results also indicate two channels of hot magmatic materials joining both the Sana’a-Amran Quaternary volcanic field and the Late Miocene Jabal An Nar volcanic area with the Dhamar-Rada’a volcanic field. This conclusion is supported by the widespread geothermal activity(of mantle origin) distributed along these channels,isotopic data, and the upper mantle low velocity zones indicated by earlier studies.

关键词： Bouguer gravity anomaly Earth gravitational model(EGM2008) Moho discontinuity Mantle upwelling Lithosphere-asthenosphere interaction Volcanic passive margin Isostasy Gulf of Aden Red Sea Arabian Peninsula

Discussion on "Effects of lime addition on geotechnical properties of sedimentary soil in Curitiba, Brazil" [J Rock Mech Geotech Eng 10(2018)188-194]

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Journal of Rock Mechanics and Geotechnical Engineering 2019年第1期11卷 214-218页

作者： amin Soltani Mehdi Mirzababaei School of Civil.Environmental and Mining Engineering The University of Adelaide School of Engineering and Technology Central Queensland University

The present discussion aims at complementing the original work published by Baldovino et al.(2018) by outlining a novel point of view. In light of the inherent limitations associated with the empirical model suggested in the original article, the dimensional analysis technique was introduced to the soil-lime strength problem, thereby leading to the development of simple and physically meaningful dimensional models capable of predicting the unconfined compressive and splitting tensile strengths of compacted soil-lime mixtures as a function of the mixture's index properties, i.e. lime content, initial placement(or compaction) condition, initial specific surface area and curing time. The predictive capacity of the proposed dimensional models was examined and validated by statistical techniques. The proposed dimensional models contain a limited number of fitting parameters, which can be calibrated by minimal experimental effort and hence implemented for predictive purposes.

关键词： Dimensional analysis Lime content Curing time Specific surface area Unconfined compressive strength Splitting tensile strength

Enhanced removal of nitrate and phosphate from wastewater by Chlorella vulgaris: Multi-objective optimization and CFD simulation

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Chinese Journal of Chemical Engineering 2019年第3期27卷 639-648页

作者： Mohammad Bagher Sabeti Mohammad amin Hejazi Afzal Karimi Faculty of Chemical and Petroleum Engineering University of Tabriz Department of Food Biotechnology Branch for Northwest & West Region Agricultural Biotechnology Research Institute of Iran Agricultural Education and Extension Organization (AREEO) Department of Biotechnology Faculty of Advanced Technologies in Medicine Iran University of Medical Sciences

To enhance the efficiency of wastewater biotreatment with microalgae, the effects of physical parameters need to be investigated and optimized. In this regard, the individual and interactive effects of temperature, p H and aeration rate on the performance of biological removal of nitrate and phosphate by Chlorella vulgaris were studied by response surface methodology(RSM). Furthermore, a multi-objective optimization technique was applied to the response equations to simultaneously find optimal combinations of input parameters capable of removing the highest possible amount of nitrate and phosphate. The optimal calculated values were temperature of 26.3 °C, pH of 8 and aeration rate of 4.7 L·min^(-1). Interestingly, under the optimum condition, approximately 85% of total nitrate and 77% of whole phosphate were removed after 48 h and 24 h, respectively, which were in excellent agreement with the predicted values. Finally, the effect of baffle on mixing performance and, as a result, on bioremoval efficiency was investigated in Stirred Tank Photobioreactor(STP) by means of Computational Fluid Dynamics(CFD). Flow behavior indicated substantial enhancement in mixing performance when the baffle was inserted into the tank. Obtained simulation results were validated experimentally. Under the optimum condition, due to proper mixing in baffled STP, nitrate and phosphate removal increased up to 93% and 86%,respectively, compared to unbaffled one.

关键词： Nitrate Phosphate Nutrient removal Response surface methodology Stirred Tank Photobioreactor Computational Fluid Dynamics

Large-scale seismic isolation through regulated liquefaction： a feasibility study

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Earthquake Engineering and Engineering Vibration 2016年第4期15卷 579-595页

作者： Seyed amin Mousavi Morteza Bastami Seyed Mehdi Zahrai School of Civil Engineering College of Engineering University of Tehran Tehran Iran International Institute of Earthquake Engineering and Seismology TehranIran Center of Excellence for Engineering and Management of Civil Infrastructures School of Civil Engineering Faculty of EngineeringUniversity of Tehran Tehran Ivan

Using controlled liquefaction, a seismic isolation technique is introduced by which a large area with dozens of structures can be seismically isolated. The proposed Large Scale Seismic Isolation （LSSI） is in many ways similar to conventional base isolations. The required bearing is provided by a fully undrained pre-saturated liquefiable layer which has substantial vertical stiffness/capacity and minimal lateral stiffness. Moreover, required energy dissipation would be provided through material damping and Biot flow-induced damping within the liquefied layer. LSSI consists of a thick non- liquefiable crust layer and an underlying engineered pre-saturated liquefiable layer bounded by two impermeable thin clay layers. The liquefiable layer should be designed to trigger liquefaction as soon as possible within the early seconds of a design level seismic event. Adopting the energy-based GMP liquefaction theory, optimum gradation of the liquefiable layer is also investigated. It tumed out that LSSI would effectively reduce acceleration response spectrum within short to medium periods. Contribution of the proposed LSSI is more pronounced in the case of stronger ground motions such as near field events as well as ground motions with longer return periods.

关键词： liquefaction seismic isolation effective stress analysis ground response analysis passive control

Analyzing uncertainties involved in estimating collapse risk with and without considering uncertainty probability distribution parameters

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Earthquake Engineering and Engineering Vibration 2022年第1期21卷 101-116页

作者： Mohammad amin Bayari Naser Shabakhty Esmaeel Izadi Zaman Abadi Department of Civil Engineering Najafabad BranchIslamic Azad UniversityNajafabad ***Iran School of Civil Engineering Iran University of Science and TechnologyTehran 16844Iran

In the present study,modified Ibarra,Medina and Krawinkler moment-rotation parameters are used for modeling the uncertainties in concrete moment frame *** of model parameters in a component and between two structural components were considered to analyze these *** the first step,the structural collapse responses were obtained by producing 281 samples for the uncertainties using the Latin hypercube sampling(LHS)method,considering the probability distribution of the uncertainties and performing incremental dynamic *** the second step,281 new samples were produced for the uncertainties by the central composite design(CCD)method without considering the probability distribution of the uncertainties and calculating the structural collapse ***,using the response surface method(RSM)and artificial neural network(ANN)for the two simulation modes,structural collapse responses were *** results indicated that the collapse responses at levels of 0 to 100%obtained from the two simulations have a high correlation coefficient of 98%.This suggests that random variables can be simulated without considering the probability distribution of uncertainties,by performing uncertainty analysis to determine structural collapse responses.

关键词： uncertainty analysis collapse response artificial neural network response surface method