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The deflection angle and quasi-periodic oscillations of an extended gravitational decoupled black hole solution

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Communications in Theoretical Physics 2025年第2期77卷 132-147页

作者： Farzan Mushtaq Xia Tiecheng allah Ditta G Mustafa S K Maurya Department of Mathematics Shanghai University and Newtouch Center for Mathematics of Shanghai University Department of Physics Zhejiang Normal University Research Center of Astrophysics and Cosmology Khazar University Department of Mathematical and Physical Sciences College of Arts and Sciences University of Nizwa

In weak field limits, we compute the deflection angle of a gravitational decoupling extended black hole(BH) solution. We obtained the Gaussian optical curvature by examining the null geodesic equations with the help of Gauss–Bonnet theorem(GBT). We also looked into the deflection angle of light by a black hole in weak field limits with the use of the Gibbons–Werner method. We verify the graphical behavior of the black hole after determining the deflection angle of light. Additionally, in the presence of the plasma medium, we also determine the deflection angle of the light and examine its graphical behavior. Furthermore, we compute the Einstein ring via gravitational decoupling extended black hole solution. We also compute the quasi-periodic oscillations and discuss their graphical behavior.

关键词： deflection of light Gauss-Bonnet theorem gravitational decoupling

SmartSurf^(ACE)transepithelial photorefractive keratectomy with mitomycin C enhancement after small incision lenticule extraction

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Eye and Vision 2021年第1期8卷 276-285页

作者： Amr a.gab‑Alla Faculty of Medicine Ophthalmology DepartmentSuez Canal UniversityRing RoadIsmailiaEgypt

Background:To evaluate predictability,stability,efficacy,and safety of transepithelial photorefractive keratectomy(TPRK)using smart pulse technology(SPT)(SmartSurface procedure)of Schwind Amaris with mitomycin C for correction of post small incision lenticule extraction(SMILE)myopic residual refractive ***:This study is a prospective,non-comparative case series conducted at a private eye centre in Ismailia,Egypt,on eyes with post-SMILE myopic residual refractive errors because of undercorrection or suction loss(suction loss occurred after the posterior lenticular cut and the creation of side-cuts;redocking was attempted,and the treatment was completed in the same session with the same parameters)with myopia or myopic *** patients were followed up post-SMILE for six months before the SmartSurface procedure,and then they were followed up for one year after *** were performed using Amaris excimer laser at 500 *** main outcomes included refractive predictability,stability,efficacy,safety and any reported ***:This study included 68 eyes of 40 patients out of 1920 total eyes(3.5%)with post-SMILE technique myopic residual refractive *** average duration between the SMILE surgery and TPRK was 6.7±0.4 months(range 6 to 8 months).The mean refractive spherical equivalent(SE)was within±0.50 D of plano correction in 100%of the eyes at 12 months *** of<0.50 D was achieved in 100%of the *** mean of the residual SE error showed statistically significant improvement from preoperative−1.42±0.52 D to 0.23±0.10 D(P<0.0001).Uncorrected distance visual acuity(UDVA)(measured by Snellen’s chart and averaged in logMAR units)was improved significantly to 0.1±0.07(P<0.0001).UDVA was 0.2 logMAR or better in 100%of the eyes,0.1 logMAR or better in 91.2%of the eyes,and 0.0 logMAR in 20.6%of the *** distance visual acuity(CDVA)remained unchanged in 79.4%of eyes.14.7%of eyes gained one line of CDVA(Snellen).

关键词： Transepithelial PRK Mitomycin C Refractive enhancement Small incision lenticule extraction Smart pulse technology SmartSurface procedure

A Greener Future: Carbon Nanomaterials from Lignocellulose

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Journal of Renewable Materials 2025年第1期13卷 21-47页

作者： Hebat-allah S.Tohamy Mohamed El-Sakhawy Samir Kamel Cellulose and Paper Department National Research CentreDokkiGiza12622Egypt

Lignocellulosic materials(LCMs),abundant biomass residues,pose signiﬁcant environmental challenges when improperly disposed ***,such as sugarcane bagasse,rice straw,saw dust and agricultural residues,are abun-dant but often burned,contributing to air pollution and greenhouse gas *** review explores the potential of transforming these materials into high-value carbon nanomaterials(CNMs).We explore the potential of transforming these materials into high-value *** employing techniques like carbonization and activa-tion,LCMs can be converted into various CNMs,including carbon nanotubes(CNTs),graphene(G),graphene oxide(GO),carbon quantum dots(CQDs),nanodiamonds(NDs),fullerenes(F),carbon nanoﬁbers(CNFs),and *** different carbon allotropes further enhances their *** derived from cellulose,lignin,and hemicellulose exhibit promising applications in diverseﬁ*** instance,CNTs can be used in energy storage devices like batteries and supercapacitors due to their exceptional electrical conductivity and mechanical ***,CNTs can be incorporated into recycled paper as aﬁre retardant additive,enhancing itsﬂame resistance.G,renowned for its high surface area and excellent electrical conductivity,ﬁnds applications in electronics,sensors,catalysis,and water treatment,where it can be used to adsorb heavy metal ***,owing to their unique optical properties,are used in bioimaging,drug delivery,and optoelectronic *** harnessing the potential of LCMs,we can not only mitigate environmental concerns but also contri-bute to a sustainable *** research is essential to optimize synthesis methods,explore novel applica-tions,and unlock the full potential of these versatile materials.

关键词： Lignocellulosic materials carbon-based nanomaterials carbon allotropes

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

Abundant solutions of Wick-type stochastic fractional 2D KdV equations

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Chinese Physics B 2014年第6期23卷 97-103页

作者： Hossam A.Ghany Abd-allah Hyder Department of Mathematics Faculty of Science Taif University Department of Mathematics Helwan University Department of Engineering Physics and Mathematics Faculty of Engineering Al-Azhar University

A modified fractional sub-equation method is applied to Wick-type stochastic fractional two-dimensional （2D） KdV equations. With the help of a Hermit transform, we obtain a new set of exact stochastic solutions to Wick-type stochastic fractional 2D KdV equations in the white noise space. These solutions include exponential decay wave solutions, soliton wave solutions, and periodic wave solutions. Two examples are explicitly given to illustrate our approach.

关键词： 2D KdV equations fractional calculus white noise Hermite transform

Effects of medicinal plants on Alzheimer＇s disease and memory deficits

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Neural Regeneration Research 2017年第4期12卷 660-670页

作者： Muhammad Akram allah Nawaz Department of Eastern Medicine and Surgery Faculty of Medical and Health Sciences The University of Poonch Rawalakot Azad Jammu and Kashmir Pakistan First Department of Internal Medicine Faculty of Medicine University of Toyama Toyama Japan

Alzheimer＇s disease is an age-related neurodegenerative disorder characterized by memory deficits. Various studies have been carried out to find therapeutic approaches for Alzheimer＇s disease. However, the proper treatment option is still not available. There is no cure for Alzheimer＇s disease, but symptomatic treatment may improve the memory and other dementia related problems. Traditional medicine is practiced world- wide as memory enhancer since ancient times. Natural therapy including herbs and medicinal plants has been used in the treatment of memory deficits such as dementia, amnesia, as well as Alzheimer＇s disease since a long time. Medicinal plants have been used in different systems of medicine, particularly Unani system of medicines and exhibited their powerful roles in the management and cure of memory disorders. Most of herbs and plants have been chemically evaluated and their efficacy has also been proven in clinical trials. However, the underlying mechanisms of actions are still on the way. In this paper, we have reviewed the role of different medicinal plants that play an important role in the treatment of Alzheimer＇s disease and memory deficits using conventional herbal therapy.

关键词： nerve regeneration memory Alzheimer's disease medicinal plants efficacy literature review neural regeneration

Inclusive Multiple Models(IMM)for predicting groundwater levels and treating heterogeneity

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Geoscience Frontiers 2021年第2期12卷 713-724页

作者： Rahman Khatibi Ata allah Nadiri GTEV-ReX Limited SwindonUK Department of Earth Sciences Faculty of Natural ScienceUniversity of Tabriz29 Bahman BoulevardTabrizEast AzerbaijanIran Institute of Environment University of TabrizEast AzerbaijanIran

An explicit model management framework is introduced for predictive Groundwater Levels(GWL),particularly suitable to Observation Wells(OWs)with sparse and possibly heterogeneous *** framework implements Multiple Models(MM)under the architecture of organising them at levels,as follows:(i)Level 0:treat heterogeneity in the data,***-Organised Mapping(SOM)to classify the OWs;and decide on model structure,*** a grey box model to predict GWLs.(ii)Level 1:construct MMs,*** Fuzzy Logic(FL)and one Neurofuzzy(NF)models.(iii)Level 2:formulate strategies to combine the MM at Level 1,for which the paper uses Artificial Neural Networks(Strategy 1)and simple averaging(Strategy 2).Whilst the above model management strategy is novel,a critical view is presented,according to which modelling practices are:Inclusive Multiple Modelling(IMM)practices contrasted with existing practices,branded by the paper as Exclusionary Multiple Modelling(EMM).Scientific thinking over IMMs is captured as a framework with four dimensions:Model Reuse(MR),Hierarchical Recursion(HR),Elastic Learning Environment(ELE)and Goal Orientation(GO)and these together make the acronym of ***,IMM-RHEO is piloted in the aquifer of Tabriz Plain with sparse and possibly heterogeneous *** results provide some evidence that(i)IMM at two levels improves on the accuracy of individual models;and(ii)model combinations in IMM practices bring‘model-learning’into fashion for learning with the goal to explain baseline conditions and impacts of subsequent management changes.

关键词： Artificial intelligence Exclusionary multiple modelling(EMM) Groundwater level prediction Inclusive multiple modelling(IMM) Model management practices

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