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Communications in Theoretical Physics 2020年第3期72卷 7-13页

作者： M S Osman k u tariq Ahmet Bekir A Elmoasry Nasser S Elazab M Younis Mahmoud Abdel-Aty Department of Mathematics Faculty of ScienceCairo UniversityGizaEgypt Department of Mathematics Faculty of Applied ScienceUmm Alqura UniversityMakkah 21955Saudi Arabia School of Mathematics and Statistics Huazhong University of Science and TechnologyWuhan 430074China Department of Mathematics Mirpur University of Science and TechnologyMirpur(AJK)10250Pakistan Neighbourhood of Akcaglan Imarli StreetNumber:28/426030EskisehirTurkey Mathematics department College of ScienceMajmaah UniversitySaudi Arabia Punjab university College of Information Technology University of the PunjabLahore 54590Pakistan Department of Mathematics Faculty of ScienceSohag UniversitySohagEgypt Applied Science university Bahrain

The principal objective of this article is to construct new and further exact soliton solutions of the(2+1)-dimensional Heisenberg ferromagnetic spin chain equation which investigates the nonlinear dynamics of magnets and explains their ordering in ferromagnetic *** solutions are exerted via the new extended FAN sub-equation *** successfully obtain dark,bright,combined bright-dark,combined dark-singular,periodic,periodic singular,and elliptic wave solutions to this equation which are interesting classes of nonlinear excitation presenting spin dynamics in classical and semi-classical continuum Heisenberg systems.3D figures are illustrated under an appropriate selection of *** applied technique is suitable to be used in gaining the exact solutions of most nonlinear partial/fractional differential equations which appear in complex phenomena.

关键词： soliton solutions Heisenberg ferromagnetic equation FAN sub-equation method

First-principles calculations of nitrogen-doped antimony triselenide： A prospective material for solar cells and infrared optoelectronic devices

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Frontiers of physics 2018年第3期13卷 129-140页

作者： Sajid-ur-Rehman Faheem k. Butt Chuanbo Li Bakhtiar u1 Haq Zeeshan tariq F. Aleem State key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences College of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences Beijing 100083 China university of Chinese Academy of Sciences Beijing 100049 China Department of Physics Division of Science and Technology University of Education College Road Township Lahore 54770 Pakistan Physik-Department ECS Technische Universitat Miinchen James-Franck-Str. 1 D-85748 Garching Germany School of Science Minzu University of China Beijing 100081 China Advanced Functional Materials & Optoelectronics Laboratory (AFMOL) Department of Physics Faculty of Science King Khalid University P.O. Box 9004 Abha Saudi Arabia Research Center for Advanced Materials Science (RCAMS) King Khalid University Abha 61413 P.O. Box 9004 Saudi Arabia Department of Physics The University of Lahore l-Kin Raiwind Road Lahore 53700 Pakistan

This study is focused on calculation of the electronic structure and optical properties of non-metal doped Sb2Se3 using the first-principles method. One and two N atoms are introduced to Sb and Se sites in a Sb2Se3 crystal. When one and two N atoms are introduced into the Sb2Se3 lattice at Sb sites, the electronic structure shows that the doping significantly modifies the bandgap of Sb2Se3 from 1.11 eV to 0.787 and 0.685 eV, respectively. When N atoms are introduced to Se sites, the material shows a metallic behavior. The static dielectric constants el（0） for Sb16Se24, SblsN1Se24, Sb14N2Se24, Sb16Se23N1, and Sb16Se22N2 are 14.84, 15.54, 15.02, 18.9, and 39.29, respectively. The calculated values of the refractive index n（0） for Sb16Se24, SblsN1Se24, Sb14N2Se24, Sb16Se23N1, and Sb16Se22N2 are 3.83, 3.92, 3.86, 4.33, and 6.21, respectively. The optical absorbance and optical conductivity curves of the crystal for N-doping at Sb sites show a significant redshift towards the short-wave infrared spectral region as compared to N-doping at Se sites. The modulation of the static refractive index and static dielectric constant is mainly dependent on the doping level. The optical properties and bandgap narrowing effect suggest that the N-doped Sb2Se3is a promising new semiconductor and can be a replacement for GaSb due to its very similar bandgap and low cost.

关键词： Sb2Se3 infrared optical properties solar cells optoelectronic devices

Correction of failure in antenna array using matrix pencil technique

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Chinese Physics B 2017年第6期26卷 491-498页

作者： S u khan M k A Rahim Advanced RF & Microwave Research Group Department of Communication Engineering Faculty of Electrical Engineering Universiti Teknologi Malaysia 81310 Skudai Johor Malaysia

In this paper a non-iterative technique is developed for the correction of faulty antenna array based on matrix pencil technique（MPT）. The failure of a sensor in antenna array can damage the radiation power pattern in terms of sidelobes level and nulls. In the developed technique, the radiation pattern of the array is sampled to form discrete power pattern information set. Then this information set can be arranged in the form of Hankel matrix（HM） and execute the singular value decomposition（SVD）. By removing nonprincipal values, we obtain an optimum lower rank estimation of HM. This lower rank matrix corresponds to the corrected pattern. Then the proposed technique is employed to recover the weight excitation and position allocations from the estimated matrix. Numerical simulations confirm the efficiency of the proposed technique, which is compared with the available techniques in terms of sidelobes level and nulls.

关键词： array correction low rank estimation matrix pencil technique singular value decomposition

Synthesis of Nano-sized Barium Titanate Powder by Solid-state Reaction between Barium Carbonate and Titania

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Journal of Materials Science & Technology 2007年第5期23卷 655-658页

作者： u.Manzoor D.k.kim Department of Physics COMSATS Institute of Information TechnologyIslamabadPakistan Department of Materials Science and Engineering Korea Advanced Institute of Science and Technology(KAIST)DaejeonKorea

Size control of BaTiO3 in solid-state reaction between BaCO3 and TiO2 was demonstrated by varying the size of TiO2 and milling conditions of BaCO3. The smaller TiO2 particles had higher surface area, resulting in faster initial reaction. The mechanically milled BaCO3 particles accelerated the diffusion process and decreased the calcinations temperature. It can be deduced from the results that the size control is possible and nano-sized BaTiO3 particles with about 60 nm can be synthesized by using the conventional solid-state reaction between BaCO3 and TiO2.

关键词： Barium tltanate Mechanical milling Solid-state reaction Nano particles

Saddle Point Criteria in Nonsmooth Semi-Infinite Minimax Fractional Programming Problems

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Journal of Systems Science & Complexity 2018年第2期31卷 446-462页

作者： MISHRA S k SINGH Yadvendra VERMA R u Department of Mathematics Banaras Hindu University Varanasi-221005 India. Department of Mathematics Texas State University USA

This paper considers a nonsmooth semi-infinite minimax fractional programming problem（SIMFP） involving locally Lipschitz invex functions. The authors establish necessary optimality conditions for SIMFP. The authors establish the relationship between an optimal solution of SIMFP and saddle point of scalar Lagrange function for SIMFP. Further, the authors study saddle point criteria of a vector Lagrange function defined for SIMFP.

关键词： Generalized convexity Lagrange function nonsmooth programming problems saddlepoint semi-infinite minimax fractional programming problems.

Hybrid Active Contour Mammographic Mass Segmentation and Classification

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Computer Systems Science & Engineering 2022年第3期40卷 823-834页

作者： k.Yuvaraj u.S.Ragupathy Department of Electronics and Instrumentation Engineering Kongu Engineering College PerunduraiErode638060India

This research implements a novel segmentation of mammographic *** methods are proposed,namely,segmentation of mass based on iterative active contour,automatic region growing,and fully automatic mask selectionbased active contour *** the first method,iterative threshold is performed for manual cropped preprocessed image,and active contour is applied *** overcome manual cropping in the second method,an automatic seed selection followed by region growing is *** that the result is only a few images owing to over segmentation,the third method uses a fully automatic active *** of the segmentation techniques are compared with the manual markup by experts,specifically by taking the difference in their mean ***,the difference in the mean value of the third method is 1.0853,which indicates the closeness of the ***,the proposed method is compared with the existing fuzzy C means and level set *** automatic mass segmentation based on active contour technique results in segmentation with high *** using adaptive neuro fuzzy inference system,classification is done and results in a sensitivity of 94.73%,accuracy of 93.93%,and Mathew’s correlation coefficient(MCC)of 0.876.

关键词： Feature optimization hybrid active contour segmentation mass classification mass feature extraction medical image analysis

Thermal Properties of Ni–Cr–Si–B–Fe Based Interlayer Material and Its Application in TLP Bonding of IN 718 Superalloy

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Acta Metallurgica Sinica(English Letters) 2020年第12期33卷 1666-1680页

作者： u.k.Tarai P.S.Robi Sukhomay Pal Department of Mechanical Engineering IIT GuwahatiGuwahati 781039India

A new Ni–Cr–Si–B–Fe fi ller material is prepared for transient liquid-phase(TLP)bonding of Inconel 718 superalloy by mechanical alloying *** melting temperature range of the fi ller material and its activation energy of melting are determined by diff erential scanning calorimetry *** activation energy and melting temperature of the alloy powder decrease with increasing milling *** 718 alloy was joined via TLP by using the newly developed fi ller *** eff ect of TLP bonding temperature and time on microstructural evolution and mechanical properties of the joint was *** distinct microstructural regions were observed in the bonding area:isothermal solidifi cation zone consisting of a single-phase solid solution,diff usion aff ected zone consisting of extensive diff usion-induced precipitates of metallic boride,and unaff ected base *** ultimate shear strength and microhardness of the TLP-bonded joint increase with bonding time and temperature.

关键词： Transient liquid-phase(TLP)bonding kissinger plot Mechanical alloying Inconel 718

Effect of Ipomea carnea Jacq. flowers on hematological changes in toluene diisocyanate-induced inflammation in Wistar rats

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Chinese Journal of Natural Medicines 2014年第3期12卷 161-166页

作者： Jain Smita Patil u.k. Department of Pharmacognosy VNS Institute of Pharmacy Department of Pharmaceutical Sciences Dr. H.S. Gour Central University

AIM： To investigate the active chloroform fraction of the ethanol extract oflpomoea carnea flowers on hematological changes in toluene diisocyanate-induced inflammation in Wistar rats. METHOD： Except for the control group, all of the rats were sensitized with intranasal application of 5 μL of 10% toluene diiso- cyanate （TDI） for 7 days. One week after second sensitization, all of the rats were provoked with 5 ~tL of 5% TDI to induce airway hypersensitivity. After the last challenge, blood and bronchoalvelor lavage （BAL） fluid were collected and subjected to total and differential leucocytes count. Flash chromatography was performed on the most active chloroform fraction to isolate an individual component. RESuLTS： Treatment with the ethanolic extract and its chloroform fraction at an oral dose of 200 mg·kg^ -1 showed a significant decrease in circulating neutrophil and eosinophil in blood and BAL as compared with standard dexamethasone （DEXA）. The structure of the compound obtained from chloroform fraction oflpomea carnea was elucidated as stigmast-5, 22-dien-3β-ol on the basis of spectral data analysis. CONCLuSION： The chloroform fraction was found to be more effective to suppress airway hyper reactivity symptoms, and de- creased count of both total and differential inflammatory cells.

关键词： Ipomea carnea Toluene diisocyanate Bronchoalvelor lavage Neutrophils Stigmasterol

Study of nucleon-nucleon and alphanucleon elastic scattering by the Manning-Rosen potential

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Communications in Theoretical Physics 2020年第7期72卷 60-64页

作者： A k Behera J Bhoi u Laha B khirali Department of Physics National Institute of TechnologyJamshedpur831014India Department of Physics Veer Surendra Sai University of TechnologyBurla-768018OdishaIndia

Although often used in molecular dynamics,in this work the Manning-Rosen potential is parameterized to compute the scattering phase shifts for the nucleon-nucleon and the alphanucleon systems by exploiting the standard phase function *** obtain excellent agreement in phase shifts with the more sophisticated calculations up to partial waves l=2.

关键词： phase function method Manning-Rosen potential scattering phase shifts nucleon-nucleon and the alpha-nucleon systems

Mathematical modeling and optimal intervention of COVID-19 outbreak

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Quantitative Biology 2021年第1期9卷 84-92页

作者： Saroj k Biswas Nasir u Ahmed Department of Electrical and Computer Engineering Temple UniversityPhiladelphiaPA19122USA School of Electrical Engineering and Computer Science University of OttawaOttawaK1N 6N5Canada

Background:The COVID-19 pandemic has become a formidable threat to global health and *** coronavirus SARS-CoV-2 that causes COVID-19 is known to spread by human-to-human transmission,and in about 40%cases,the exposed individuals are asymptomatic which makes it difficult to contain the ***:This paper presents a modified SEIR epidemiological model and uses concepts of optimal control theory for analysis of the effects of intervention methods of the *** the pandemic intervention problem can be viewed as a mathematical optimization problem as there are contradictory outcomes in terms of reduced infection and fatalities but with serious economic ***:Concepts of optimal control theory have been used to determine the optimal control(intervention)levels of i)social contact mitigation and suppression,and ii)pharmaceutical intervention modalities,with minimum impacts on the *** results show that with optimal intervention policies,there is a significant reduction in the number of infections and *** computed optimum intervention policy also provides a timeline of systematic enforcement and relaxation of stay-at-home regulations,and an estimate of the peak time and number of hospitalized critical care ***:The proposed method could be used by local and state governments in planning effective strategies in combating the *** optimum intervention policy provides the necessary lead time to establish necessary field hospitals before getting overwhelmed by new patient *** results also allow the local and state governments to relax social contact suppression guidelines in an orderly manner without triggering a second wave.

关键词： coronavirus COVID-19 SEIR model epidemic model optimization