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Tuning structural,electrical,dielectric and magnetic properties of mg-Cu-Co ferrites via dysprosium(Dy^(3+))doping

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Journal of Rare Earths 2024年第1期42卷 137-146,I0005页

作者： maria Akhtar m.S.Hasan Nasir Amin N.A.morley muhammad Imran arshad Department of Physics Government College UniversityFaisalabad38000Pakistan Department of Physics The University of Lahore53700Pakistan Department of materials Science and Engineering The University of SheffieldS13JDUK Department of Physics&Astronomy University College LondonUK

In current research work,Dy3+substituted mg0.5Cu0.25Co0.25Fe2-xDyxO4(0.0≤x≤0.04 with the step interval of 0.01)soft ferrites were synthesized by the sol-gel auto combustion *** prepared samples were characterized by the techniques using X-ray diffraction(XRD),scanning electron microscopy(SEm),energy dispersive X-ray spectroscopy(EDS),Fourier transform infrared(FTIR)spectroscopy,curre nt-voltage(Ⅰ-Ⅴ)measurement,LCR meter,vibrating sample magnetometer(VSm)and *** data reveal that the average crystallite size is 49.71 nm and the lattice constant is 0.83703 nm for sample x=*** non-uniform grain growth was demonstrated by micrographs and impurity-free elemental composition was observed from EDX *** DC resistivity has an increasing and decreasing trend in ferromagnetic and paramagnetic regions with an increase in ***,the high resistivity is observed with the order of 1010Ω·cm,and the activation energy is 0.944 eV for samples x=*** dielectric parameters including dielectric constant,dielectric losses,and impedance gradually decrease with the increase in frequency from 8 Hz to 8 *** minimum dielectric loss at high frequency is found for sample x=*** coercivity(Hc)and saturation magnetization(ms)are found in the ranges of 520.82-544.02 Oe and 20.5841-21.1473 emu/g,*** observations confirm that dysprosium(x=0.03)doped mCC-soft ferrites may be applicable in transformer cores,microwave absorbance,and telecommunication devices.

关键词： Soft ferrites DC resistivity Dielectric loss Impedance Coercivity Rare earths

Natural history and surgical treatment of a giant colonic diverticulum:A case report

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World Journal of Clinical Cases 2024年第17期12卷 3151-3155页

作者： arshad m Bachelani Department of Surgery Independence HealthGreensburgPA 15601United States

BACKGROUND While diverticular disease is prevalent in the West,the formation of giant colonic diverticula is *** date,approximately 200 cases have been reported,with only a handful treated surgically using a minimally invasive ***,the natural history of giant colonic diverticula is not well *** SUmmARY This report describes the case of a 66-year-old man who developed a giant colonic diverticulum with primary symptoms including dull and chronic pain in the right lower quadrant at *** patient had undergone several computed tomography scans of the abdomen and pelvis over the previous two years,through which the natural history of this rare entity could be retrospectively *** patient was successfully treated with a robot-assisted sigmoid colectomy and had an uneventful recovery with resolution of symptoms during the *** This rare case demonstrates the natural history of giant colonic diverticulum formation and supports the feasibility of robot-assisted surgery.

关键词： Giant colonic diverticulum Robotic colectomy Computed tomography Enhanced recovery Case report

Nonplanar Ion-Acoustic Solitons in Electron-Positron-Ion Quantum Plasmas

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Chinese Physics Letters 2009年第4期26卷 150-153页

作者： S. A. Khan S. mahmood arshad m. mirza Department of Physics COMSATS Institute of Information Technology Islamabad Pakistan National Centre for Physics Quaid-i-Azam University Campus Islamabad Pakistan Department of Physics Government College Bagh AJK Pakistan Theoretical Plasma Physics Division PINSTECH PO Nilore Islamabad Pakistan Theoretical Plasma Physics Group Department of Physics Quaid-i-Azam University Islamabad 45320 Pakistan

The propagation of nonplanar quantum ion-acoustic solitary waves in a dense, unmagnetized electron-positronion （e-p-i） plasma are studied by using the Korteweg-de Vries （KdV） model. The quantum hydrodynamic （QHD） equations are used taking into account the quantum diffraction and quantum statistics corrections. The analytical and numerical solutions of KdV equation reveal that the nonplanar ion-acoustic solitons arc modified significantly with quantum corrections and positron concentration, and behave differently in different geometries.

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Nonplanar Ion Acoustic Solitary Waves in a Two-Electron Temperature Plasma

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Chinese Physics Letters 2009年第12期26卷 73-76页

作者： W. masood S. Hussain S. mahmood arshad m. mirza Theoretical Plasma Physics Division Pinstech P. O. Nilore Islamabad Pakistan Pakistan Institute of Engineering and Applied Sciences (PLEAS) P. O. Nilore Islamabad Pakistan Theoretical Plasma Physics Group Department of Physics Quaid-i-Azam University Islamabad 45320 Pakistan

Linear and non-linear properties of ion acoustic wave （IAW） propagating in a two-electron temperature plasma are investigated from both analytical and numerical perspectives by employing the fluid theory. A one-dimensional modified Korteweg de Vries equation is derived for the IAW using the reductive perturbative technique in a nonplanar geometry. It is observed that the ion acoustic soliton in a two-temperature plasma admits rarefactive （dip like） solitons. In the limit that the cold electron population goes to zero, it is observed that the ion acoustic soliton yields compressive （hump like） solitons. The variation of the ion acoustic soliton with different plasma parameters is also shown. The present investigation may be beneficial to explain some aspects of ion acoustic rarefactive solitary structures observed in space environments where two-electron temperature plasmas have been observed.

关键词： Chinese climate network complex systems small world community

Refinement and estimation of asphalt flow number using partial load history

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第1期9卷 120-133页

作者： m.A.Dalhat Khaleel Al-Adham Hamad I.Al-Abdul Wahhab arshad Jamal Department of Transportation and Traffic Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityDammamSaudi Arabia Department of Civil and Environmental Engineering King Fahd University of Petroleum and MineralsDhahranSaudi Arabia

The effect of tertiary flow length on asphalt concrete(AC) flow number(FN) has been studied in this paper. The standard FN test(AASHTO T378) designated by American Association of State Highway and Transportation Officials(AASHTO) is currently among the widely adopted test for assessing the rutting performance of AC mixtures. The standard adopts the Fracken model(Fm) for fitting the permanent deformation curve(PDC), prior to FN estimation. The FN was observed to vary as tertiary flow progresses. The Fm, along with other PDC models(mFm-1 and mFm-2) obtained by modifying the Fm, was utilized to analyze and minimized this variation. Variation of FN resulted because of mathematization of the PDC data. Instead of representing the actual initiating point of permanent shear deformation of the strain data, estimated values of FN were observed to indicate the inflection points of the fitted parent curve. As per standard FN range suggested by AASHTO T378, the observed variation in FN leads to the situation, where a single asphalt mix specimen can be regarded as appropriate for two different traffic levels, depending on the tertiary flow point at which the test is terminated. Supplementary steps in the FN estimation methods were proposed for refinement of FN values. For the refinement and further standardization of FN value and FN test respectively, FN:T(flow number to test duration ratio) has been recognized as the key and most simple solution. Two potential options for employing FN:T in the estimation of FN have also been highlighted. Several important correlations have been reported herein as well. Comparatively, mFm-1 was found to be more robust in FN:T curve utilization than mFm-2 and Fm.

关键词： Road engineering HmA Permanent deformation Flow number Francken model Tertiary flow

Big Data Testing Techniques:Taxonomy,Challenges and Future Trends

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Computers, materials & Continua 2023年第2期74卷 2739-2770页

作者： Iram arshad Saeed Hamood Alsamhi Wasif Afzal SRI TUSAthloneIreland mälardalen University VästeråsSweden

Big Data is reforming many industrial domains by providing decision support through analyzing large data *** Data testing aims to ensure that Big Data systems run smoothly and error-free while maintaining the performance and quality of ***,because of the diversity and complexity of data,testing Big Data is *** numerous research efforts deal with Big Data testing,a comprehensive review to address testing techniques and challenges of BigData is not available as ***,we have systematically reviewed the Big Data testing techniques’evidence occurring in the period 2010–*** paper discusses testing data processing by highlighting the techniques used in every processing ***,we discuss the challenges and future *** findings show that diverse functional,non-functional and combined(functional and non-functional)testing techniques have been used to solve specific problems related to Big *** the same time,most of the testing challenges have been faced during the mapReduce validation *** addition,the combinatorial testing technique is one of the most applied techniques in combination with other techniques(i.e.,random testing,mutation testing,input space partitioning and equivalence testing)to find various functional faults through Big Data testing.

关键词： Big data testing techniques testing process

Adsorption Isotherm and Kinetic Study of methane on Palm Kernel Shell-Derived Activated Carbon

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Journal of Bioresources and Bioproducts 2023年第1期8卷 66-77页

作者： mohd Saufi md Zaini muhammad arshad Syed Shatir A.Syed-Hassan School of Chemical Engineering College of EngineeringUniversiti Teknologi MARA Cawangan TerengganuKampus Bukit BesiDungun 23200Malaysia Department of Basic Science Jhang-Campus University of Veterinary and Animal ScienceLahore 35200Pakistan School of Chemical Engineering College of EngineeringUniversiti Teknologi MARAShah Alam 40450Malaysia

Activated carbon(AC)was synthesized from palm kernel shell(PKS)using different activating agents,i.e.,steam,carbon dioxide(CO 2),and CO 2-steam,in order to analyze the impact of acti-vating agents on the pore opening of *** this study,AC produced from PKS was found to have great potential as an adsorbent for methane *** different molecular diffusivity and reac-tivity of the combination of CO 2 and steam succeeded in producing AC with the highest burn-offof 78.57%,a surface area of 869.82 m 2/g,a total pore volume of 0.47 cm 3/g,and leading to maximum methane gas adsorption capacity of 4.500 mol/*** types of ACs exhibited the best fit with the Freundlich isotherm model,with the correlation coefficient(R 2)ranging from 0.997 to 0.999,indicating the formation of multilayer *** addition,the adsorption kinetic data for all ACs followed the pseudo-first-order model showing that the rate of adsorption was dependent on both the adsorbent and the adsorbate and was governed primarily by physical ad-sorption between the pore surface and methane *** results of intraparticle diffusion model indicated that the adsorption of methane was affected by both pore diffusion and exterior layer diffusion due to the different adsorption rates.

关键词： Palm kernel shell Activated carbon methane adsorption Kinetic model Isotherm model

Tailoring the optical and magnetic properties of La-Bam hexaferrites by Ni substitution

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Chinese Physics B 2022年第2期31卷 570-575页

作者： Hafiz T.Ali mRamzan m Imran arshad Nicola A.morley m.Hassan Abbas mohammad Yusuf Atta Ur Rehman Khalid mahmood Adnan Ali Nasir Amin mAjaz-un-Nabi Department of mechanical Engineering College of EngineeringTaif UniversityTaif 21944Saudi Arabia Department of Physics Government College UniversityFaisalabadPakistan Department of materials Science and Engineering University of SheffieldSir Robert Hadfield BuildingMapping St.SheffieldS13JDUK Department of Clinical Pharmacy College of PharmacyTaif UniversityTaif 21944Saudi Arabia

We investigate the impact of Ni insertion on the structural,optical,and magnetic properties of Ba_(0.8)La_(0.2)Fe_(12-x)Ni_(x)O_(19)hexaferrites(Ni substituted La-Bam hexaferrites).Samples were prepared using the conventional co-precipitation method and sintered at 1000℃for 4 hours to assist the crystallization *** analysis of the structure of the samples was carried out using an x-ray diffraction(XRD)*** m-type hexagonal structure of all the samples was confirmed using XRD *** lattice parameters a and c were found to be in the ranges of 5.8925±0.001 nm–5.8952±0.001 nm and 23.2123±0.001 nm–23.2219±0.001 nm,*** m-type hexagonal nature of the prepared samples was also indicated by the presence of corresponding FT-IR bands and Raman modes in the FT-IR and Raman spectra,*** results confirmed the successful synthesis of the samples according to the required stoichiometric ratio.A UV-vis spectrometer was used to record the absorption spectra of the prepared samples in the wavelength range of 200 nm–1100 *** optical energy bandgap of the samples was found to be in the range of 1.21 eV–3.39 *** m–H loops of the samples were measured at room temperature at an applied magnetic field range of 0 kOe–60 kOe.A high saturation magnetization of 99.92 emu/g was recorded in the sample with x=0 at a microwave operating frequency of 22.2 *** high value of saturation magnetization is due to the substitution of La3+ions at the spin-up(12k,2a,and 2b)*** Ni substitution is proven to be a potential candidate for the tuning of the optical and magnetic parameters of m-type ***,we suggest that the prepared samples are suitable for use in magneto-optic applications.

关键词： m-type hexaferrite nanostructured materials magnetic properties optical properties

Deep Deterministic Policy Gradient to Regulate Feedback Control Systems Using Reinforcement Learning

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Computers, materials & Continua 2022年第4期71卷 1153-1169页

作者： Jehangir arshad Ayesha Khan mariam Aftab mujtaba Hussain Ateeq Ur Rehman Shafiq Ahmad Adel m.Al-Shayea muhammad Shafiq Department of Electrical&Computer Engineering COMSATS University IslamabadLahore Campus54000Pakistan Department of Electrical Engineering Government College UniversityLahore54000Pakistan Industrial Engineering Department College of EngineeringKing Saud UniversityP.O.Box 800Riyadh11421Saudi Arabia Department of Information and Communication Engineering Yeungnam UniversityGyeongsan38541Korea

Controlling feedback control systems in continuous action spaces has always been a challenging ***,reinforcement learning is mainly an area of artificial intelligence(AI)because it has been used in process control for more than a ***,the existing algorithms are unable to provide satisfactory ***,this research uses a reinforcement learning(RL)algorithm to manage the control *** propose an adaptive speed control of the motor system based on depth deterministic strategy gradient(DDPG).The actor-critic scenario using DDPG is implemented to build the RL *** addition,a framework has been created for traditional feedback control systems to make RL implementation easier for control *** RL algorithms are robust and proficient in using trial and error to search for the best *** proposed algorithm is a deep deterministic policy gradient,in which a large amount of training data trains the *** the system is trained,the agent can automatically adjust the control *** algorithm has been developed using Python 3.6 and the simulation results are evaluated in the mATLAB/Simulink *** performance of the proposed RL algorithm is compared with a proportional integral derivative(PID)controller and a linear quadratic regulator(LQR)*** simulation results of the proposed scheme are promising for the feedback control problems.

关键词： Feedback control systems reinforcement learning artificial intelligence