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Effects of Locations of Spur Dyke on Bed and Scour around Bridge Piers in meandering Channel

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Hydro Science & marine Engineering 2022年第1期4卷 1-7页

作者： m.athar Farha Naz Humaira Atahr Civil Engineering Department Aligarh Muslim UniversityAligarhU.P.India Innovative Building materials Division CSIR-CBRIRoorkeeUttarakhand247667India

Spur dykes are the structures which are used to protect the eroding bank of rivers.They are sometimes also used to safeguard the life of many structures such as bridge piers,abutments etc.The efficiency of spur dykes has been checked in straight channels by conducting model tests in laboratories by many investigators.Very few studies were done in curved channels.In present work an attempt has been made to study the effect of location of spur dyke on bed and scour around bridge pier in curved open channel(bend angle=80o)with time.Experiment has been carried out in 80o channel bend at constant discharge(3.5×10^(-3) m^(3)/s)and bridge pier is located at angular displacementϴ=60o.Hereϴis the angle the line drawn at the inlet of any bend to the line joining the centre of curvature and any point on the outer portion of the bend.It is found that maximum scouring occurs atϴ=0o and 20oalong inner wall and atϴ=60o and 80o along outer wall.It is also found that scouring around bridge pier is more in the vicinity of pier and decreases with increase in distance from pier.The most suitable location for spur dyke to protect bridge pier is at angular displacementϴ=20o.Scour developed rapidly during initial time and then rate of scouring decreases with elapse of time.

关键词： Spur dykes Bridge piers Angular displacement Scour and deposition

Exact analytical solutions for axial flow of a fractional second grade fluid between two coaxial cylinders

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Theoretical & Applied mechanics Letters 2011年第2期1卷 41-46页

作者： m.Imran m.Kamran m.athar Abdus Salam School of mathematical Sciences GC University

The velocity field and the adequate shear stress corresponding to the longitudinal flow of a fractional second grade fluid,between two infinite coaxial circular cylinders,are determined by applying the Laplace and finite Hankel transforms.Initially the fluid is at rest,and at time t=0^+, the inner cylinder suddenly begins to translate along the common axis with constant acceleration. The solutions that have been obtained are presented in terms of generalized G functions.moreover, these solutions satisfy both the governing differential equations and all imposed initial and boundary conditions.The corresponding solutions for ordinary second grade and Newtonian fluids are obtained as limiting cases of the general solutions.Finally,some characteristics of the motion,as well as the influences of the material and fractional parameters on the fluid motion and a comparison between models,are underlined by graphical illustrations.

关键词： second grade fluid fractional derivative longitudinal flow velocity field shear stress Laplace and finite Hankel transforms

Effect of meander on Bridge Pier Scour

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Hydro Science & marine Engineering 2021年第2期3卷 20-31页

作者： m.athar m.K.Sabiree H.athar Civil Engineering Department A.M.U.AligarhU.P.India U.P.Irrigation DepartmentU.P.India C.B.R.I. RoorkeeUttarakhandIndia

have been done in the past by many researchers.many factors which affect scour around piers such as shape of piers,size,positioning and orientation etc.have been studied in detail by them.However,similar studies in meandering channels are scanty.Very few researchers have studied the effect of angular displacement which has considerable effects of scour around bridge piers.In this paper an attempt has been made to carry out a detailed study of angular displacement on scour.A constant diameter bridge pier of circular shape has been tested in a meandering channel bend with bend angle as 800.The test bed was prepared by using uniform sand having d50 as 0.27 mm and run was taken for a discharge of 2.5 l/s.

关键词： meandering channel Angular displacement Scour and deposition Bridge piers Inner bank and outer bank

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豆科植物结瘤能力的研究

热带作物译丛 1986年第5期 52-54页

作者： m.athar 刘海亮

豆科植物是最大的植物类群之一,广泛分布于世界各地。约有750属,共16000—19000种.豆科植物的显著特征是根瘤具有固氮能力。据报道,含羞草科和蝶形花科有根瘤的种分别是83％和95％,而云实科只有40％具有生瘤能力。巴基斯坦的植物区系中... 详细信息

豆科植物是最大的植物类群之一,广泛分布于世界各地。约有750属,共16000—19000种.豆科植物的显著特征是根瘤具有固氮能力。据报道,含羞草科和蝶形花科有根瘤的种分别是83％和95％,而云实科只有40％具有生瘤能力。巴基斯坦的植物区系中,豆科植物很丰富。既有草本豆类、蔬菜作物、观赏植物,又有大量的木本树种,其中有本地种,也有外来种。

关键词：豆科植物生瘤蝶形花科根瘤大托叶云实结瘤

Smart Energy management System Using machine Learning

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Computers, materials & Continua 2024年第1期78卷 959-973页

作者： Ali Sheraz Akram Sagheer Abbas muhammad Adnan Khan Atifa athar Taher m.Ghazal Hussam Al Hamadi School of Computer Science National College of Business Administration&EconomicsLahore54000Pakistan Riphah School of Computing&Innovation Faculty of ComputingRiphah International UniversityLahore CampusLahore54000Pakistan Pattern Recognition and machine Learning Lab Department of SoftwareGachon UniversitySeongnamGyeonggido13120Korea Department of Computer Science COMSATS University IslamabadLahore CampusLahore54000Pakistan School of Information Technology Skyline University CollegeSharjah1797United Arab Emirates Network and Communication Technology Lab Center for Cyber SecurityFaculty of Information Science and TechnologyUniversiti Kebangsaan MalaysiaBangiSelangor43600Malaysia College of Engineering and IT University of DubaiDubaiUnited Arab Emirates

Energy management is an inspiring domain in developing of renewable energy sources.However,the growth of decentralized energy production is revealing an increased complexity for power grid managers,inferring more quality and reliability to regulate electricity flows and less imbalance between electricity production and demand.The major objective of an energy management system is to achieve optimum energy procurement and utilization throughout the organization,minimize energy costs without affecting production,and minimize environmental effects.modern energy management is an essential and complex subject because of the excessive consumption in residential buildings,which necessitates energy optimization and increased user comfort.To address the issue of energy management,many researchers have developed various frameworks;while the objective of each framework was to sustain a balance between user comfort and energy consumption,this problem hasn’t been fully solved because of how difficult it is to solve it.An inclusive and Intelligent Energy management System(IEmS)aims to provide overall energy efficiency regarding increased power generation,increase flexibility,increase renewable generation systems,improve energy consumption,reduce carbon dioxide emissions,improve stability,and reduce energy costs.machine Learning(mL)is an emerging approach that may be beneficial to predict energy efficiency in a better way with the assistance of the Internet of Energy(IoE)network.The IoE network is playing a vital role in the energy sector for collecting effective data and usage,resulting in smart resource management.In this research work,an IEmS is proposed for Smart Cities(SC)using the mL technique to better resolve the energy management problem.The proposed system minimized the energy consumption with its intelligent nature and provided better outcomes than the previous approaches in terms of 92.11% accuracy,and 7.89% miss-rate.

关键词： Intelligent energy management system smart cities machine learning

Survey of Indoor Localization Based on Deep Learning

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Computers, materials & Continua 2024年第5期79卷 3261-3298页

作者： Khaldon Azzam Kordi mardeni Roslee mohamad Yusoff Alias Abdulraqeb Alhammadi athar Waseem Anwar Faizd Osman Centre for Wireless Technology Faculty of EngineeringMultimedia UniversityCyberjaya63100Malaysia Communication Systems&Networks Research Lab Malaysia-Japan International Institute of TechnologyUniversiti Teknologi MalaysiaKuala Lumpur54100Malaysia Department of Electrical Engineering(DEE) International Islamic UniversityIslamabad44000Pakistan Rohde&Schwarz(m)Sdn Bhd Shah Alam40150Malaysia

This study comprehensively examines the current state of deep learning (DL) usage in indoor positioning.It emphasizes the significance and efficiency of convolutional neural networks (CNNs) and recurrent neuralnetworks (RNNs). Unlike prior studies focused on single sensor modalities like Wi-Fi or Bluetooth, this researchexplores the integration of multiple sensor modalities (e.g.,Wi-Fi, Bluetooth, Ultra-Wideband, ZigBee) to expandindoor localization methods, particularly in obstructed environments. It addresses the challenge of precise objectlocalization, introducing a novel hybrid DL approach using received signal information (RSI), Received SignalStrength (RSS), and Channel State Information (CSI) data to enhance accuracy and stability. moreover, thestudy introduces a device-free indoor localization algorithm, offering a significant advancement with potentialobject or individual tracking applications. It recognizes the increasing importance of indoor positioning forlocation-based services. It anticipates future developments while acknowledging challenges such as multipathinterference, noise, data standardization, and scarcity of labeled data. This research contributes significantly toindoor localization technology, offering adaptability, device independence, and multifaceted DL-based solutionsfor real-world challenges and future advancements. Thus, the proposed work addresses challenges in objectlocalization precision and introduces a novel hybrid deep learning approach, contributing to advancing locationcentricservices.While deep learning-based indoor localization techniques have improved accuracy, challenges likedata noise, standardization, and availability of training data persist. However, ongoing developments are expectedto enhance indoor positioning systems to meet real-world demands.

关键词： Deep learning indoor localization wireless-based localization

Influence of cerium ions on structure-dependent magnetic properties of Ba-Sr m-type hexaferrite nanocrystals

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Journal of Rare Earths 2024年第2期42卷 364-372,I0005页

作者： Ram A.Pawar Sunil m.Patange P.m.Dighe Sher Singh meena Abdullah GAl-Sehemi mehboobali Pannipara Santosh S.Jadhav Department of Physics ArtsCommerce and Science CollegeAhmednagar413711MaharashtraIndia Department of Physics Shri Krishna MahavidyalayaGunjotiDistOsmanabad413606MaharashtraIndia Padmashri Vikhe Patil College of Arts Science and CommercePravaranagarA/P.Loni(Kd)Tal.RahataDistAhmednagar413713MaharashtraIndia Solid State Physics Division Bhabha Atomic Research CentreMumbai400085MaharashtraIndia Department of Chemistry King Khalid UniversityAbha61413Saudi Arabia Department of Physics D.S.M's ArtsCommerce and Science CollegeJintur431509MaharashtraIndia

The present study is a systematic effort to investigate the structure-sensitive magnetic parameters of Ce^(3+) substituted Ba-Sr hexaferrite nanocrystals chemically formulated as Ba_(0.5)Sr_(0.5)Ce_(x)Fe_(12-x)O_(19) where x=0.0-0.2 with Δx=0.05.The hexaferrite powders were prepared using the sol-gel self-ignition route and structurally characterized by means of powder X-ray diffraction and Fourier transform infrared spectroscopy.The creation of the m-type hexaferrite phase within the synthesized samples was revealed from the Rietveld refinement of the X-ray diffractograms.The occurrence of a secondary phase of CeO_(2) was revealed within the hexaferrites for the substitution,x> 0.The refined X-ray diffraction data were utilized to compute the lattice parameters,X-ray density,and lattice parameter ratio.The crystal structure plotted from the refined XRD data reveals the occupancy of the ions at different lattice sites.The XPS data of the hexaferrite were analyzed to confirm the oxidation states of the constituent elements.The nanocrystalline nature of the hexaferrites was revealed from the crystallite sizes calculated using Scherer's formula.The analysis of FTIR spectra confirms that only a fraction of Ce^(3+)accommodated in the lattice and the remaining Ce content reside in the form of the CeO_(2) phase.The morphology of the hexaferrites was analyzed from the FESEm profiles of the ferrite samples.The magnetic behavior study was performed by analyzing the Curie temperature,hysteresis loops,and hyperfine interactions by means of susceptibility,V.S.m,and mossbauer spectroscopy,respectively.The hexaferrites with increasing coercivity,decreasing saturation magnetization,and decreasing Curie temperature are reported in the study.The substituted Ce^(3+)ions inhibit the grain growth and create lattice imperfections giving rise to hexaferrites with tuned magnetic parameters suitable for different applications.

关键词： Ba-Sr hexaferrite Ce^(3+)substitution XPS Saturation magnetization Coercivity m?ssbauer spectroscopy

Frequency-dependent viscoelasticity effects on the wave attenuation performance of multi-layered periodic foundations

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Applied mathematics and mechanics(English Edition) 2024年第3期45卷 407-424页

作者： m.SAFI m.VAKILIFARD m.J.mAHmOODI Faculty of Civil Water&Environmental EngineeringShahid Beheshti UniversityTehran ***Iran Faculty of mechanical and Energy Engineering Shahid Beheshti UniversityTehran ***Iran

In this paper,layered periodic foundations(LPFs)are numerically examined for their responses to longitudinal and transverse modes in the time and frequency domains.Three different unit-cells,i.e.,2-layer,4-layer,and 6-layer unit-cells,comprising concrete/rubber,concrete/rubber/steel/rubber,and concrete/rubber/steel/rubber/lead/rubber materials,respectively,are taken into account.Also,the viscoelasticity behavior of the rubber is modeled with two factors,i.e.,a frequency-independent(FI)loss factor and a linear frequency-dependent(FD)loss factor.Following the extraction of the complex dispersion curves and the identification of the band gaps(BGs),the simulations of wave transmission in the time and frequency domains are performed using the COmSOL software.Subsequent parametric studies evaluate the effects of the rubber viscoelasticity models on the dispersion curves and the wave transmission for the longitudinal and transverse modes.The results show that considering the rubber viscoelasticity enhances the wave attenuation performance.moreover,the transverse-mode damping is more sensitive to the viscoelasticity model than its longitudinal counterpart.The 6-layer unit-cell LPF exhibits the lowest BG,ranging from 4.8 Hz to 6.5 Hz.

关键词： layered metamaterial periodic foundation complex dispersion curve wave transmission diagram

Engineering of efficient visible light photocatalysts:Ti_(1-x+y)Cu_(x)La_(y)O_(2)(x=0.03;y=0,0.005,0.01) compositions

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Journal of Rare Earths 2024年第3期42卷 497-505,I0003页

作者： S.m.Yakout A.m.Youssef Inorganic Chemistry Department National Research Centre(NRC)El Buhouth StDokkiCairo12622Egypt

In dye-photocatalysis, widening the wavelengths absorption range of catalysts as well as aborting the recombination of the photoexcited charge carriers(electrons-holes pairs) are of paramount significance.In the current study, we report the photocatalytic characteristics of four compositions composed of TiO_(2),Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders for two harmful dyes(Congo red and methylene blue). The X-ray diffraction technique verified the configuration of mixed anatase and rutile phases in pure TiO_(2)and Ti_(0.97)Cu_(0.03)O_(2)powders while Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders possess anatase phase only. The changes of the band gap structure and dimensions of the unit cell volume of TiO_(2)confirm the substitution of Ti^(4+)sites by Cu^(2+)and La^(3+)ions. Remarkable widening of wavelengths absorption with formation of long absorption tails were found in TiO_(2)(3.13 e V) through insertion of La^(3+)plus Cu^(2+)ions. Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)samples exhibit a visible light band gap of 2.3 and 2.7 e V, respectively. Based on SEm images, incorporation of Cu^(2+)and La^(3+)ions influences the surface morphology of TiO_(2). The resulting Ti_(0.97)Cu_(0.03)O_(2), Ti_(0.965)Cu_(0.03)La_(0.005)O_(2)and Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)powders present enhanced photocatalytic activity towards Congo red dye degradation compared to pure one under natural solar spectrum. The best Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst exhibits superior photocatalytic activity of 96% for 10 ppm CR dye in 20 min as well as above average photocatalytic efficiency of 63% for 30 ppm CR dye in 120 min. As well, it showed acceptable photodegradation activity of 52% for 30 ppm mB solution in 140 min of sunlight irradiation. The heightened photodegradation efficiency of Ti_(0.96)Cu_(0.03)La_(0.01)O_(2)catalyst can be clarified in terms of higher charge carriers' separation(Cu^(2+)+ e-→ Cu^(+), L

关键词： Semiconductor TiO_(2) Rare earths Congo red methylene blue Solar spectrum Photodegradation