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Reissner-Nordstrom-de-Sitter-type Solution by a Gauge Theory of Gravity

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Chinese Physics Letters 2008年第10期25卷 3570-3573页

作者： V. Enache Camelia Popa V. Paun M. Agop Department of Theoretical Physics Faculty of Physics Al.I.Cuza University Blvd. Carol No.l 700506 Iasi Romania Department of Physics Faculty of Applied Sciences Politehnica University of Bucharest I 313 Splaiul lndependentei Street 060042 Bucharest Romania Department of Physics Gh. Asachi Technical University Blvd. Mangeron 700029 Iasi Romania Department of Physics University of Athens Athens 15771 Greece

We use the theory based on a gravitational gauge group （Wu＇s model） to obtain a spherical symmetric solution of the field equations for the gravitational potential on a Minkowski spacetime. The gauge group, the gauge covariant derivative, the strength tensor of the gauge feld, the gauge invariant Lagrangean with the cosmological constant, the field equations of the gauge potentiaIs with a gravitational energy-momentum tensor as well as with a tensor of the field of a point like source are determined. Finally, a Reissner-Nordstrom-de Sitter-type metric on the gauge group space is obtained.

关键词： WEYL-DIRAC THEORY GRAVITATIONAL-FIELD EQUATIONS Gauge Theory

Unsteady flow of viscoelastic fluid between two cylinders using fractional Maxwell model

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Acta Mechanica Sinica 2012年第2期28卷 274-280页

作者： Muhammad Jamil Constantin Fetecau Corina Fetecau Abdus Salam School of Mathematical Sciences GC UniversityLahorePakistan Department of Mathematics NED University of Engineering&TechnologyKarachi-75270Pakistan Department of Mathematics Technical University of IasiIasi-700050Romania Department of Theoretical Mechanics Technical University of IasiIasi-700050Romania

The unsteady flow of an incompressible fractional Maxwell fluid between two infinite coaxial cylinders is studied by means of integral transforms. The motion of the fluid is due to the inner cylinder that applies a time dependent tor- sional shear to the fluid. The exact solutions for velocity and shear stress are presented in series form in terms of some generalized functions. They can easily be particularized to give similar solutions for Maxwell and Newtonian fluids. Fi- nally, the influence of pertinent parameters on the fluid motion, as well as a comparison between models, is highlighted by graphical illustrations.

关键词： Maxwell fluid Fractional derivative Exact so- lutions Velocity field Shear stress Laplace and Hankel transforms

Cellular modelling using P systems and process algebra

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Progress in Natural Science:Materials International 2007年第4期17卷 375-383页

作者： Francisco J. Romero-Campero Marian gheorghe Gabriel Ciobanu John M. Auld Mario J. Pérez-Jiménez Research Group on Natural Computing Department of Computer Science and Artificial IntelligenceUniversity of SevilleAvda.Reina Mercedes41012 SevillaSpain Department of Computer Science The University of Sheffield Regent CourtPortobello StreetSheffield S1 4DPUK Romanian Academy Institute of Computer ScienceBlvd. Carol I nr. 11700505IasiRomania

In this paper various molecular chemical interactions are modelled under different computational paradigms. P systems andπ-calculus are used to describe intra-cellular reactions like protein-protein interactions and ... 详细信息

关键词： cellular modelling P systems process algebra.

盐水介质中Ti12Mo5Ta合金的电化学特性(英文)

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Transactions of Nonferrous Metals Society of China 2015年第1期25卷 345-353页

作者： Daniel MARECI Romeu CHELARIU Adrian CAILEAN Florin BRINZA Georgiana BOLAT Doina Margareta GORDIN Faculty of Chemical Engineering and Environmental Protection Gheorghe Asachi Technical University of Iasi Faculty of Materials Science and Engineering Gheorghe Asachi Technical University of Iasi Faculty of Physics Alexandru Ioan Cuza University of Iasi INSA Rennes UMR CNRS 6226 Sciences Chimiques de Rennes/Chimie-Métallurgie F-35043Rennes Cedex France

比较了未再结晶和再结晶Ti12Mo5Ta合金、未再结晶Ti12Mo合金和工业用纯钛(cp-Ti)在0.9%生理盐水(pH 2.3)中37°C下的电化学行为。从阳极极化曲线中得到了极低的钝化电流密度(10-6 A/cm2),这表明所有样品在酸性0.9%NaCl溶液中具有高的耐... 详细信息

比较了未再结晶和再结晶Ti12Mo5Ta合金、未再结晶Ti12Mo合金和工业用纯钛(cp-Ti)在0.9%生理盐水(pH 2.3)中37°C下的电化学行为。从阳极极化曲线中得到了极低的钝化电流密度(10-6 A/cm2),这表明所有样品在酸性0.9%NaCl溶液中具有高的耐蚀性能。采用扫描电子显微镜(SEM)观察样品的表面形貌,发现所有样品表面受到了相同的腐蚀,而且经阳极动电位极化测试后的样品表面没有出现点蚀、裂纹或其它缺陷。使用等效电路模拟电化学阻抗谱(EIS)数据,以表征样品表面且更好地理解Mo和Ta的添加对cp-Ti及再结晶的影响。EIS结果证实,在开路电位下,所有样品在0.9%NaCl溶液(pH 2.3)中产生钝化(极化电阻约为105Ω·cm2)。在37°C时,样品在0.9%NaCl溶液中(pH 2.3)的耐蚀性顺序为:再结晶Ti12Mo5Ta>未再结晶Ti12Mo5Ta>未再结晶Ti12Mo>cp-Ti。

关键词：钛合金再结晶阳极动电位曲线 Ta Mo 电化学行为

Incessant Allocation Method for Solving Transportation Problems

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American Journal of Operations Research 2016年第3期6卷 236-244页

作者： Mollah Mesbahuddin Ahmed Aminur Rahman Khan Faruque Ahmed Md. Sharif Uddin Department of Mathematics Jahangirnagar University Savar Dhaka Bangladesh Department of Management Engineering ‘Gheorghe Asachi’ Technical University of Iasi Iasi Romania Department of Mathematics Ruse University Ruse Bulgaria

Industries require planning in transporting their products from production centres to the users end with minimal transporting cost to maximize profit. This process is known as Transportation Problem which is used to analyze and minimize transportation cost. This problem is well discussed in operation research for its wide application in various fields, such as scheduling, personnel assignment, product mix problems and many others, so that this problem is really not confined to transportation or distribution only. In the solution procedure of a transportation problem, finding an initial basic feasible solution is the prerequisite to obtain the optimal solution. Again, development is a continuous and endless process to find the best among the bests. The growing complexity of management calls for development of sound methods and techniques for solution of the problems. Considering these factors, this research aims to propose an algorithm “Incessant Allocation Method” to obtain an initial basic feasible solution for the transportation problems. Several numbers of numerical problems are also solved to justify the method. Obtained results show that the proposed algorithm is effective in solving transportation problems.

关键词： Transportation Models Initial Basic Feasible Solution Optimal Solution Incessant Allocation Method

Positive Solutions for Systems of Coupled Fractional Boundary Value Problems

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Open Journal of Applied Sciences 2015年第10期5卷 600-608页

作者： Johnny Henderson Rodica Luca Alexandru Tudorache Department of Mathematics Baylor University Waco Texas USA Department of Mathematics Gh. Asachi Technical University Iasi Romania Faculty of Computer Engineering and Automatic Control Gh. Asachi Technical University Iasi Romania

We investigate the existence and nonexistence of positive solutions for a system of nonlinear Riemann-Liouville fractional differential equations with coupled integral boundary conditions which contain some positive c... 详细信息

关键词： Riemann-Liouville Fractional Differential Equations Coupled Integral Boundary Conditions Positive Solutions

Exact solution for the rotational flow of a generalized second grade fluid in a circular cylinder

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Acta Mechanica Sinica 2009年第6期25卷 777-785页

作者： I.Siddique D.vieru COMSATS Institute of Information Technology LahorePakistan technical university of iasi 6600 IasiRomania

This paper deals with the rotational flow of a generalized second grade fluid, within a circular cylinder, due to a torsional shear stress. The fractional calculus approach in the constitutive relationship model of a second grade fluid is introduced. The velocity field and the resulting shear stress are determined by means of the Laplace and finite Hankel transforms to satisfy all imposed initial and boundary conditions. The solutions corresponding to second grade fluids as well as those for Newtonian fluids are obtained as limiting cases of our general solutions. The influence of the fractional coefficient on the velocity of the fluid is also analyzed by graphical illustrations.

关键词： Generalized second grade fluid - Exact solutions . Fractional calculus - Velocity field ~ Shear stress

Nonnegative Solutions for a Riemann-Liouville Fractional Boundary Value Problem

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Open Journal of Applied Sciences 2019年第10期9卷 749-760页

作者： Rodica Luca Alexandru Tudorache Department of Mathematics Gh. Asachi Technical University Iasi Romania Faculty of Computer Engineering and Automatic Control Gh. Asachi Technical University Iasi Romania

We investigate the existence of nonnegative solutions for a Riemann-Liouville fractional differential equation with integral terms, subject to boundary conditions which contain fractional derivatives and Riemann-Stieltjes integrals. In the proof of the main results, we use the Banach contraction mapping principle and the Krasnosel’skii fixed point theorem for the sum of two operators.

关键词： Riemann-Liouville Fractional Differential Equations Nonlocal Boundary Conditions Nonnegative Solutions Existence

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专家观点

服饰导刊 2020年第3期9卷 9-15页

作者： '首届时尚与可持续发展国际学术论坛'学术委员会 “首届时尚与可持续发展国际学术论坛”学术委员会

1 Mirela BLAGA *** Blaga gheorghe asachi technical university,Romania President of AUTEX Professor Mirela has expertise in the area of Knitting Technologies,CAD Systems,Functional textiles,e-Learning applied in *** is currently the President of Association of the Textile Universities in Europe(AUTEX),President of Romanian Section of the International Federation of Knitting Technologists(IFKT),Chartered Member of Textile Institute of Manchester(Ctext ATI).她的报告分为三个部分。第一部首先对罗马尼亚gheorghe asachi技术大学进行简要介绍,随后对AUTEX作了简介,最后对欧盟服装研究重点主题进行了介绍。

关键词：专家观点 CAD Manchester