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Chinese Journal of Aeronautics 2018年第11期31卷 2111-2123页

作者： Waqas SARWAR ABBASI shams ul islam Lubna FAIZ Hamid RAHMAN Mathematics Department Air UniversityIslamabad Mathematics Department COMSATS Institute of Information Technology Mathematics and Statistics Department Bacha Khan University

This study focuses on the transitions in flow states around two-, three-and four-inline square cylinders under the effect of Reynolds numbers at two different gap spacing values using the lattice Boltzmann method. For this purpose, Reynolds number is varied in the range 1–130 while two different values of spacing taken into account are gap spacing =2 and 5. Before going to actual problem, the code is tested for flow around a single square cylinder by comparing the results with experimental and numerical results of other researchers, and good agreement is *** current numerical computations yield that for both spacing values and all combinations of cylinders there exist three different sates of flow depending on Reynolds numbers: steady state, transitional state and unsteady state. It is found that the range of Reynolds numbers for these flow states is different for both spacing values. At gap spacing =2 the range of Reynolds numbers for each flow state decreases by increasing the number of cylinders while at gap spacing =5 opposite trend is observed. The results also show that at gap spacing =2 the reduction in drag force is greater than the corresponding reduction at gap spacing =5. The maximum reduction in drag force is observed at Reynolds numbers =1 at both spacing values. Similarly, at both spacing values and all Reynolds numbers, the maximum reduction in drag force is observed for the case of four-inline square cylinders.

关键词： Drag reduction Flow states Gap spacing Inline cylinders Reynolds number

平板间方柱绕流的格子Boltzmann方法模拟

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哈尔滨工业大学学报 2010年第11期42卷 1753-1757页

作者：周超英葛家 islam shams ul 哈尔滨工业大学深圳研究生院广东深圳518055

为研究平板间方柱绕流上下平板对置于其中的方柱绕流所产生的影响,采用格子Boltzmann方法对二维平板间低雷诺数(Re=100)方柱绕流问题进行了数值模拟研究.分析了3种不同阻塞比下,平板边壁对方柱的升、阻力系数、Strouhal数和尾涡流场的影... 详细信息

为研究平板间方柱绕流上下平板对置于其中的方柱绕流所产生的影响,采用格子Boltzmann方法对二维平板间低雷诺数(Re=100)方柱绕流问题进行了数值模拟研究.分析了3种不同阻塞比下,平板边壁对方柱的升、阻力系数、Strouhal数和尾涡流场的影响.结果表明:平板对方柱绕流特性有明显的影响,随着阻塞比的增加,阻力系数和Strouhal数均增大,与无边壁相比阻力系数可增加达30%,而升力系数却随之减小.计算结果与相关实验数据相吻合,验证了格子Boltzmann方法对钝体绕流非定常问题模拟的有效性。

关键词：格子Boltzmann方法方柱绕流壁面效应阻塞比

Synthesis and Crystal Structure of 2-(4-Oxo-3-o- tolyl-3,4-dihydroquinazolin-2-ylthio)acetohydrazide

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Chinese Journal of Structural Chemistry 2012年第9期31卷 1329-1333页

作者： Aamer Saeed shams-ul-Mahmood ulrich Flörke Department of Chemistry Quaid-I-Azam UniversityIslamabad 45320Pakistan Department Chemie Fakultät fur NaturwissenschaftenUniversität PaderbornWarburgerstrasse 100D-33098 PaderbornGermany

The title compound was synthesized from 3-（2-methylphenyl）-2-thioxo-2,3-dihy- droquinazolin-4（1H）-one （4） which was prepared from 2-methylaniline in two steps. The structure was supported by the spectroscopic data and unambiguously confirmed by single-crystal X-ray diffraction studies. It crystallizes in the orthorhombic space group Pbca with unit cell dimensions a = 6.687（4）, b = 24.788（16）, c = 30.453（19）  V = 5048（5） 3 and Z = 8.

关键词： quinazolinone acetohydrazide synthesis

A two step facile synthesis of new steroidal linear and angular pyranones having anti-mycobacterial activity

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Chinese Chemical Letters 2009年第2期20卷 153-157页

作者： shams-uz-zaman Tabassum Siddiqui Mohd.Gulfam Alam Najmul islam Department of Chemistry(Steroid Lab) Aligarh Muslim University Department of Biochemistry Faculty of medicineJ.N.Medical College

Title compounds 2′,2′-dimethylcholesta-2,4-dien[3,2-b]-pyran-4′-one （3）, 2′,2′-dimethyl-3β-substituted cholesta-4,6-dien[7,6- b]-pyran-4′-one （6a,b） and （6c） were prepared by the cyclization of 2-acetylcholesta-2,4-dien-3-ol （2）, 6-acetyl-3β-substituted- cholesta-4,6-dien-7-ol （Sa,b） and （5c） respectively, with pyrrolidine, dry benzene and dry acetone using Dean Stark separator through conventional heating. Furthermore, compounds were also found to be active against Mycobacterium tuberculosis.

关键词： Steroidal linear and angular pyranones Acetyl hydroxy derivative of steroids Pyrrolidine Acetyl chloride Dean Stark separator Anti-mycobacterial activity

Improved Transportation Model with Internet of Things Using Artificial Intelligence Algorithm

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Computers, Materials & Continua 2023年第8期76卷 2261-2279页

作者： Ayman Khallel Al-Ani shams ul Arfeen Laghari Hariprasath Manoharan Shitharth Selvarajan Mueen Uddin Cybersecurity Research Group Faculty of Computing and InformaticsUniversity Malaysia SabahJalan UMSKota KinabaluSabah88400Malaysia National Advanced IPv6 Centre(NAv6) Universiti Sains MalaysiaGelugorPenang11800Malaysia Department of Electronics and Communication Engineering Panimalar Engineering CollegePoonamalleeChennai600123TamilnaduIndia Department of Computer Science&Engineering Kebri Dehar UniversityKebri Dehar250Ethiopia College of Computing and Information Technology University of Doha for Science and TechnologyDoha24449Qatar

In this paper,the application of transportation systems in realtime traffic conditions is evaluated with data handling *** proposed method is designed in such a way as to detect the number of loads that are present in a vehicle where functionality tasks are computed in the *** to the existing approach,the design model in the proposed method is made by dividing the computing areas into several cluster regions,thereby reducing the complex monitoring system where control errors are ***,a route management technique is combined with Artificial Intelligence(AI)algorithm to transmit the data to appropriate central ***,the combined objective case studies are examined as minimization and maximization criteria,thus increasing the efficiency of the proposed ***,four scenarios are chosen to investigate the projected design’s *** all simulated metrics,the proposed approach provides better operational outcomes for an average percentage of 97,thereby reducing the amount of traffic in real-time conditions.

关键词： Transportation Artificial Intelligence(AI) data-driven Internet of Things(IoT)

Production of hydrogen from fossil fuel:A review

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Frontiers in Energy 2023年第5期17卷 585-610页

作者： shams ANWAR Xianguo LI Laboratory for Fuel Cell and Green Energy Department of Mechanical and Mechatronics EngineeringUniversity of WaterlooWaterlooOntario N2L3G1Canada

Production of hydrogen,one of the most promising alternative clean fuels,through catalytic conversion from fossil fuel is the most technically and economically feasible *** conversion of natural gas into hydrogen and carbon is thermodynami-cally favorable under atmospheric ***,using noble metals as a catalyst is costly for hydrogen production,thus mandating non-noble metal-based catalysts such as Ni,Co,and Cu-based *** paper reviews the various hydrogen production methods from fossil fuels through pyrolysis,partial oxidation,autother-mal,and steam reforming,emphasizing the catalytic production of hydrogen via steam reforming of *** multicomponent catalysts composed of several non-noble materials have been *** the Ni,Co,and Cu-based catalysts investigated in the literature,Ni/Al_(2)O_(3)catalyst is the most economical and performs best because it suppresses the coke formation on the *** avoid carbon emission,this method of hydrogen production from methane should be integrated with carbon capture,utilization,and storage(CCUS).Carbon capture can be accomplished by absorption,adsorption,and membrane separation *** remaining challenges,prospects,and future research and development directions are described.

关键词： methane catalytic conversion natural gas hydrogen production CCUS

Automating identification of services and their variability for product lines using NSGA-II

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Frontiers of Computer Science 2017年第3期11卷 444-464页

作者： Sedigheh KHOSHNEVIS Fereidoon shams Software Engineering Department Shahid Beheshti University Tehran 19836 Iran

Architecture-level business services are identi- fied based on business processes; and likewise, in service- oriented product lines, identifying the domain architecture- level business services and their variability is preferred to be based on business processes and their variability. Identifica- tion of business services for a product line satisfying a set of given design metrics （such as cohesion and coupling） is ex- tremely difficult for a domain architect, since there are many product configurations for which the services must be proper at the same time. This means that the identified services must have proper values for n metrics in m different configura- tions at the same time. The problem becomes more serious when there are high degrees of variability and complexity embedded in the business processes that are the basis for ser- vice identification. We contribute to solve the multi-objective optimization problem of identifying business services for a product line by partitioning the graph of a business process variability model utilizing Non-dominated Sorting Genetic Algorithm-II. The service specification is achieved based on the results of the partitioning. The variability of the services is then determined in terms of mandatory and optional services as well as variability relationships, which are all represented in a Service Variability Model. The method was empirically evaluated through experimentation, and showed proper lev- els of reusability and variability. Furthermore, the resulting models were fully consistent.

关键词： software product model business process genetic line service variability algorithm

用格子Boltzmann方法数值模拟三维空化现象

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物理学报 2009年第12期58卷 8406-8414页

作者：张新明周超英 islam shams 刘家琦哈尔滨工业大学深圳研究生院深圳518055 哈尔滨工业大学数学系哈尔滨150001

空化是一种微观、瞬时、随机、多相的复杂现象,其过程中所产生的极端条件以及伴随的一系列空化效应,将对液流系统产生破坏性和建设性两方面的作用.采用基于Shan-Chen模型的单组分多相流格子Boltzmann方法对水体中的三维空化现象进行了... 详细信息

空化是一种微观、瞬时、随机、多相的复杂现象,其过程中所产生的极端条件以及伴随的一系列空化效应,将对液流系统产生破坏性和建设性两方面的作用.采用基于Shan-Chen模型的单组分多相流格子Boltzmann方法对水体中的三维空化现象进行了数值模拟,研究了低压下水体中气核半径与空化现象的相互关系,成功再现了低压下水体中微小气核发展成气泡的过程,并进一步研究了水体依次流经低压区、高压区时空化产生、发展、溃灭的全过程.数值模拟结果和理论预测结果符合良好.

关键词：单组分多相流格子Boltzmann方法三维空化

NUMERICAL SIMulATION OF SPHERICAL, CYLINDRICAL AND AXIAL BUBBLE CLOUDS COLLAPSE

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Journal of Hydrodynamics 2012年第4期24卷 569-578页

作者： MAHDI Miralam EBRAHIMI Reza shams Mehrzad Faculty of Mechanical Engineering K.N.Toosi University of Technology Tehran Iran

The nonlinear dynamics of a spherical, cylindrical and axial cloud of cavitation bubbles were numerically simulated in order to learn more about the physical phenomena occurring in the cloud cavitation. The simulations employed the fully nonlinear continuum mixture equations coupled with the Gilmore equation for the dynamics of bubbles by considering the compressibility of liquid. A set of the Navier-Stokes equations was solved for the gas inside a spherical bubble, considering heat transfer through the gas inside the bubble and the liquid layer. The flow field around the cylindrical and axial cloud was obtained by solving the Navier-Stokes equations using a finite volume method and a dynamic layering mesh scheme. The calculated strength of shock wave in the liquid around the cloud was of the order of 1 ×10^6 Pa and the propagation of this shock wave lasted for l0 p.s. The conducted investigations illustrate that the shock wave propagates before the cloud has completely collapsed. A good agreement with experimental data was observed.

关键词： cloud cavitation shock wave spherical cloud cylindrical cloud axial cloud

Inverting a k-heptadiagonal matrix based on Doolitle LU factorization

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Applied Mathematics(A Journal of Chinese Universities) 2022年第3期37卷 340-349页

作者： Maryam shams Solary Mehran Rasouli Department of mathematics Payamenoor universityTehranIran

The purpose of the present paper is to show a new numeric and symbolic algorithm for inverting a general nonsingular k-heptadiagonal *** work is based on Doolitle LU factorization of the *** obtain a series of recursive relationships then we use them for constructing a novel algorithm for inverting a k-heptadiagonal *** computational cost of the algorithm is *** illustrative examples are given to demonstrate the effectiveness of the proposed method.

关键词： k-Heptadiagonal matrices LU factorization algorithm inverse of a matrix