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Predicting the response of continuous RC deep beams under varying levels of differential settlement

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Frontiers of Structural and Civil Engineering 2019年第3期13卷 686-700页

作者： M.Z.NASER R.A.HAWILEH Glenn Department of Civil Engineering Clemson UniversityClemsonSC 29634USA Department of Civil Engineering American University of SharjahSharjahUnited Arab Emirates materials Science and Engineering Research Institute American University of SharjahSharjahUnited Arab Emirates

This paper investigates the effect of differential support settlement on shear strength and behavior of continuous reinforced concrete(RC)deep beams.A total of twenty three-dimensional nonlinear finite element models were developed taking into account various constitutive laws for concrete material in compression(crushing)and tension(cracking),steel plasticity(i.e.,yielding and strain hardening),bond-slip at the concrete and steel reinforcement interface as well as unique behavior of spring-like support elements.These models are first validated by comparing numerical predictions in terms of load-deflection response,crack propagation,reaction distribution,and failure mode against that of measured experimental data reported in literature.Once the developed models were successfully validated,a parametric study was designed and performed.This parametric study examined number of critical parameters such as ratio and spacing of the longitudinal and vertical reinforcement,compressive and tensile strength of concrete,as well as degree(stiffness)and location of support stiffness to induce varying levels of differential settlement.This study also aims at presenting a numerical approach using finite element simulation,supplemented with coherent assumptions,such that engineers,practitioners,and researchers can carry out simple,but yet effective and realistic analysis of RC structural members undergoing differential settlements due to variety of load actions.

关键词： concrete continuous beams deep beams finite element modeling support settlement

Causality in structural engineering: discovering new knowledge by tying induction and deduction via mapping functions and explainable artificial intelligence

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AI in Civil Engineering 2022年第1期1卷 82-97页

作者： M.Z.NASER School of Civil and Environmental Engineering and Earth Sciences(SCEEES) Clemson UniversityClemsonUSA Artificial Intelligence Research Institute for Science and Engineering(AIRISE) Clemson UniversityClemsonUSA

Causality is the science of cause and effect.It is through causality that explanations can be derived,theories can be formed,and new knowledge can be discovered.This paper presents a modern look into establishing causality within structural engineering systems.In this pursuit,this paper starts with a gentle introduction to causality.Then,this paper pivots to contrast commonly adopted methods for inferring causes and effects,i.e.,induction(empiricism)and deduc-tion(rationalism),and outlines how these methods continue to shape our structural engineering philosophy and,by extension,our domain.The bulk of this paper is dedicated to establishing an approach and criteria to tie principles of induction and deduction to derive causal laws(i.e.,mapping functions)through explainable artificial intelligence(XAI)capable of describing new knowledge pertaining to structural engineering phenomena.The proposed approach and criteria are then examined via a case study.

关键词： Causality Explainable artificial intelligence mapping functions Knowledge discovery Structural engineering

Complexity of charged anisotropic spherically symmetric fluids in f(G)gravity

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Communications in Theoretical Physics 2023年第3期75卷 91-104页

作者： z Yousaf m z Bhatti m m m Nasir Department of mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan

The previous ideology of complexity factor for the dynamical spheres[Herrera et al 2018,Phys.Rev.D,98,104059]is extended for the influence of charge.A dynamical spherically symmetric non-dissipative and dissipative self-gravitating structure is examined in the presence of maxwell f(G)gravity to examine the complexity factor.The pattern of evolution is studied with the minimal complexity constraint.The complexity factor remains the same for the structure of fluid distribution,while we examine homologous constraints for the most basic evolution pattern.We calculate the structure scalars which play an important role in order to understand the fundamental properties of the system.The fluid is geodesic as well as shearing for the dissipative case and there is a large number of solutions.In the non-dissipative fluid distribution,a shear-free,homogeneous and isotropic,geodesic fluid correlates with the evolving homologous and vanishing complexity condition.The implication of the condition of vanishing complexity factor and stability are discussed at the end.

关键词： gravitation anisotropy complexity hydrodynamics

Is Li-ESWT effective in diabetic patients with severe erectile dysfunction?

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Asian Journal of Andrology 2022年第5期24卷 521-524页

作者： müslüm Ergün Osman Akyüz Department of Urology School of MedicineAtlas UniversityIstanbul 34200Turkey

Noninvasive low-intensity extracorporeal shockwave treatment(Li-ESWT)has been widely used to treat erection disorders.There is no clear information regarding either the selection of patients for the treatment or the treatment protocol.In this study,we aimed to investigate the efficacy of extracorporeal shockwave therapy in diabetic patients with severe erectile dysfunction(International Index of Erectile Function-5[IIEF-5]scores of 5 to 7).Sixty-three diabetes mellitus patients with erectile dysfunction having IIEF-5 scores of 5 to 7 and not showing a recovery of potency despite phosphodiesterase type 5 inhibitor therapy for the past 6 months were included in the study.The patients were evaluated based on their IIEF-5 scores and Erection Hardness Scale scores.The IIEF-5 score(mean±standard deviation[s.d.])increased from 5.29±1.67 to 5.56±1.85,with a difference of 0.27±0.18(P>0.05).The Erection Hardness Scale scores(mean±s.d.),on the other hand,increased from 1.46±0.50 to 1.48±0.50,with a difference of 0.02±0(P>0.05).In conclusion,the response to phosphodiesterase type 5 inhibitors did not change after extracorporeal shockwave treatment in diabetes mellitus patients with severe erectile dysfunction(IIEF-5 scores of 5 to 7).

关键词： diabetes mellitus International Index of Erectile Function-5 score low-intensity extracorporeal shockwave treatment severe erectile dysfunction

Dysregulation of RNA modification systems in clinical populations with neurocognitive disorders

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Neural Regeneration Research 2024年第6期19卷 1256-1261页

作者： Helen m.Knight merve Demirbugen ?z Adriana PerezGrovas-Saltijeral Division of Cells Organisms and Molecular Genetics School of Life Sciences University of Notingham Department of Pharmaceutical Toxicology Faculty of Pharmacy Ankara University

The study of modified RNA known as epitranscriptomics has become increasingly relevant in our understanding of disease-modifying mechanisms. methylation of N6 adenosine(m6A) and C5 cytosine(m5C) bases occur on mRNAs, tRNA, mt-tRNA, and rRNA species as well as non-coding RNAs. With emerging knowledge of RNA binding proteins that act as writer, reader, and eraser effector proteins, comes a new understanding of physiological processes controlled by these systems. Such processes when spatiotemporally disrupted within cellular nanodomains in highly specialized tissues such as the brain, give rise to different forms of disease. In this review, we discuss accumulating evidence that changes in the m6A and m5C methylation systems contribute to neurocognitive disorders. Early studies first identified mutations within FmR1 to cause intellectual disability Fragile X syndromes several years before FmR1 was identified as an m6A RNA reader protein. Subsequently, familial mutations within the m6A writer gene mETTL5, m5C writer genes NSUN2, NSUN3, NSUN5, and NSUN6, as well as THOC2 and THOC6 that form a protein complex with the m5C reader protein ALYREF, were recognized to cause intellectual development disorders. Similarly, differences in expression of the m5C writer and reader effector proteins, NSUN6, NSUN7, and ALYREF in brain tissue are indicated in individuals with Alzheimer’s disease, individuals with a high neuropathological load or have suffered traumatic brain injury. Likewise, an abundance of m6A reader and anti-reader proteins are reported to change across brain regions in Lewy bodies diseases, Alzheimer’s disease, and individuals with high cognitive reserve. m6A-modified RNAs are also reported significantly more abundant in dementia with Lewy bodies brain tissue but significantly reduced in Parkinson’s disease tissue, whilst modified RNAs are misplaced within diseased cells, particularly where synapses are located. In parahippocampal brain tissue, m6A modification is enriched in transcripts associated with psychiatri

关键词： 5-methylcytosine methylation Alzheimer’s disease cognitive diseases epitranscriptomics intellectual disability Lewy body diseases N6 adenosine RNA modification

Reducing damage extent of epoxy coating on magnesium substrate by zr-enhanced PEO coating as an effective pretreatment

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Journal of magnesium and Alloys 2023年第2期11卷 641-656页

作者： z.Jamshidipour m.Toorani m.Aliofkhazraei m.mahdavian Department of materials Engineering Tarbiat Modares UniversityTehranIran Department of Surface Coatings and Corrosion Institute for Color Science and Technology(ICST)TehranIran

This research was undertaken to study the effect of zr-enhanced plasma electrolytic oxidation(PEO) as a pretreatment on the corrosion performance of epoxy coating applied on magnesium in 3.5 wt.% Na Cl solution. The parameters of delamination index along with coating damage index were extracted through electrochemical impedance spectroscopy(EIS) tests to determine how zr may affect the corrosion protection of duplex PEO/epoxy coated samples. Pull-off adhesion tests were also accomplished to form a better understanding of zr-enhanced PEO coating’ function. According to the obtained results, the presence of zr can reduce the damage to the coating system by almost twice.

关键词： magnesium EIS Pretreatment PEO Epoxy zirconyl nitrate

A new model for the expansion tube considering the stress coupling:Theory,experiments and simulations

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Defence Technology（防务技术） 2022年第7期18卷 1190-1204页

作者： m.z.Wu X.W.zhang Q.m.zhang State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyHaidian DistrictBeijing10081China

Based on the two-arc profile assumption,the expansion deformation and energy absorption of circular tubes compressed by conical-cylindrical dies were reconsidered.First,the deformation of the two arcs was analyzed independently and an improved model denoted as model-I was established.Then,by further involving the coupling between the bending moment and membrane forces,a more elaborate model,i.e.,model-II was developed.Afterwards,experiments and simulations were conducted to verify the models,which show that,compared with previous theoretical models,model-II could not only capture the prominent features of the deformation,but also improve the prediction accuracy of the steady driving force significantly.By means of this model,it was found that the critical semi-conical angle,which makes the driving force minimum,increases with the increase of the friction coefficient,expansion ratio as well as the radius/thickness ratio of the tube.And,the energy dissipation due to stretching is always greater than that of bending,while the friction dissipation can account for the largest proportion at small semi-conical angle or large friction coefficient.At a certain friction and die conditions,the specific energy absorption of expanded tubes can be much higher than that under progressive collapse mode.

关键词： Expansion Circular tube Stress coupling Strain hardening Energy absorption

Thin-shell wormholes and modified Chaplygin gas with relativistic corrections

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Communications in Theoretical Physics 2023年第12期75卷 84-96页

作者： m z Bhatti z Yousaf m Yousaf Department of mathematics University of the PunjabQuaid-i-Azam CampusLahore-54590Pakistan

In this paper,we analyze thin-shell wormholes from two identical copies of charged static cylindrically symmetric spacetimes using Visser’s‘cut and paste’approach under the influence of f(R,T)gravity Harko,Lobo,Nojiri,and Odintsov(2011,Phys.Rev.D 84,024020).In this scenario,the modified Chaplygin gas supports the exotic matter in the shell which allows,one to examine the dynamics of constructed wormholes.We utilize the junction condition to connect the interior and exterior geometries across the hypersurface and calculate different components of the Lanczos equation recently computed by Roza in Rosa(2021,Phy.Rev.D 103,104069).We analyze the stability of the thin-shell wormhole models under linear perturbations while keeping the cylindrical symmetry and also examine the influence of charge on their stability.The positive quantity of the second derivative of potential at the throat radius might be interpreted as the stability criterion.We find both unstable and stable wormhole solutions for different parameters included in the equation of state and specific forms of considered gravity and illustrate them theoretically as well as graphically.We examine the impact of electric charge on the stability region of a constructed wormhole,which suggests that a wormhole model with a charge may exhibit more stable behavior compared to an uncharged system.

关键词： wormholes gravitation mathematical and relativistic aspects of cosmology

利用FmI图像研究测井构造断裂对伊朗西南部某油田阿斯马里组储层质量的影响

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Journal of Central South University 2023年第4期30卷 1279-1295页

作者： z.SOLUKI m.AzIzzADEH A.mAzDARANI F.KHOSHBAKHT Department of Geology Islamic Azad University(Tehran North Branch)TehranIran Department of Geology Research Institute of Petroleum Industry(RIPI)TehranIran Department of Geology Islamic Azad University Science&Research BranchIran

裂缝性碳酸盐岩中的储层质量受裂缝性质控制,天然裂缝性碳酸盐岩储层的裂缝系统特征对开发计划非常重要。本文分析了有效构造对波斯湾西北部伊朗Asmari储层油田质量的影响。这些是通过对FmI井眼成像测井(全井眼微成像仪)的分析和解释来... 详细信息

裂缝性碳酸盐岩中的储层质量受裂缝性质控制,天然裂缝性碳酸盐岩储层的裂缝系统特征对开发计划非常重要。本文分析了有效构造对波斯湾西北部伊朗Asmari储层油田质量的影响。这些是通过对FmI井眼成像测井(全井眼微成像仪)的分析和解释来完成的。研究的地区是NE-SW趋势背斜;Asmari储层包括两部分(上部和下部)以及它们之间的Ghar砂岩部分。使用Geolog软件处理并校正了研究井的图像测井,然后识别并解释了不同类型的自然结构,并测量了它们的姿态。结构的方向数据已通过绘制统计图(例如罗斯和极图)从结构的角度进行分析。结果表明,该井的层理几乎是水平的。此外,存在不同类型的裂缝和缝合线,它们在结构上可能与褶皱有关。观察到的主要结构可分为:纵向和横向的开放性裂缝,纵向填充的裂缝,与顺层针脚石平行和垂直。用孔隙度测井曲线(即中子,密度和声波测井曲线)对各种类型结构的频率分布进行比较,结果表明,开放的裂缝使孔隙度增加,但填充的裂缝和针孔石的孔隙度大幅度降低。通常,从井的顶部到底部显示的孔隙度增加,即Ghar砂岩段。因此,根据结构对阿斯马里储层质量的影响,建议针对储层的密度和方向(尤其是开放性裂缝)计划在储层中进行任何未来的钻探。

关键词： FmI日志 Asmari地层结构特征储层质量