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ON CONJECTURE ABOUT A CODE COMMUTATIVELY EQUIVALENT TO A PREFIX CODE

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Science in China,Ser.A 1987年第10期 3-1015页

作者：章亮郭聿琦王利民 Shanghai college of Architecture and Municipal Engineering Lanzhou University zhangye college for teacher-training Gansu Province

In this paper, we have shown that the conjecture stated by Perrin and Schutzenberger is equivalent to the fact that every simple code is commutatively equivalent to a prefix code. And this equivalence for simple codes... 详细信息

关键词： show code 刃一 ON CONJECTURE ABOUT A CODE COMMUTATIVELY EQUIVALENT TO A PREFIX CODE over

ORTHOGONAL GEOMETRIES OVER FINITE FIELDS WITH CHARACTERISTIC≠2 AND BLOCK DESIGNS

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Acta Mathematicae Applicatae Sinica 1993年第3期9卷 269-280页

作者：阳本傅魏万迪 teacher-training college of Chengdu Pengrian County 611930 China Sichuan University Chengdu 610064China

By taking as blocks certain subspace-pairs of an orthogonal geometry over a finite field with characteristic≠2 we construct some new types of BIB designs and PBIB designs whose parameters are also given.

关键词： ORTHOGONAL GEOMETRIES OVER FINITE FIELDS WITH CHARACTERISTIC AND BLOCK DESIGNS BIB

Characterization of semisolid deformation behavior of a high Zr-containing WE magnesium alloy

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Rare Metals 2022年第12期41卷 4201-4208页

作者： Masoud Moradjoy-Hamedani Abbas Zarei-Hanzaki Seyed Mahmood Fatemi School of Metallurgy and Materials Engineering College of EngineeringUniversity of TehranTehran 515-14395Iran School of Mechanical Engineering Shahid Rajaee Teacher Training UniversityTehran 136-16785Iran

The effects of temperature and strain rate on the semisolid deformation behavior of a high Zr WE54 magnesium alloys were studied at temperatures of 570,595 and 620℃.A flow stress peak was appeared during deformation of the feedstock experimental material at deformation conditions of 570℃,0.010 and 0.100 s-1,and 595℃,0.100 *** latter results were connected to the occurrence of dynamic recrystallization in solid ***,these conditions were gauged to be able to activate"lubricated flow"*** 570℃and strain rate of 0.001 s-1as well as 595℃and rates of 0.010 and 0.001 s^(-1),the flow stress increases and reaches a plateau,where dynamic recovery is considered as the dominant ***,at 620℃under all the strain rates,the flow stress drops for a limited strain range and then increases *** results show that as the liquid removes from the boundaries between the solid parts,the densification of the globules occurs at higher strains,causing an increase in the flow *** analysis points out that the feedstock material exhibits a lower flow stress than as-cast alloy associating with a modified morphology of Zr particles after deformation.

关键词： Mg-RE alloy Feedstock Semisolid deformation Liquid flow

Quasi-Local Energy Distribution and Thermodynamics of Reissner-Nordstrom Black Hole Surrounded by Quintessence

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Communications in Theoretical Physics 2011年第2期55卷 291-295页

作者： Mahamat Saleh Bouetou Bouetou Thomas Timoleon Crepin Kofane Department of Physics Faculty of Science University of Yaounde Dpartment of Physics Higher Teacher's Training College University of Maroua Ecole Nationale Superieure Polytechnique University of Yaounde

We investigate quasi-local energy distribution and thermodynamics of the Reissner-Nordstr6m black hole space-time surrounded by quintessence. We use the quasi-local energy distribution from Einstein energy-momentum complex. We plot the variation of the energies, temperature and heat capacity with the state parameter related to the quintessence ωq. We show that due to the presence of quintessence, the total energy of the outer region as well as the temperature and heat capacity decreases with the increase of the density of quintessence, while the total energy of the black hole region increases.

关键词： quasi-local energy distribution thermodynamics Reissner-NordstrSm black hole quintessence

Travelling Wave Solutions to Stretched Beam's Equation: Phase Portraits Survey

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Communications in Theoretical Physics 2011年第4期55卷 605-608页

作者： Gambo Betchewe Kuetche Kamgang Victor Bouetou Bouetou Thomas Timoleon Crepin Kofane Higher teacher's training college of Maroua University of Maroua Ecole Nationale Superieure Polytechnique University of Yaounde I Department of Physics Faculty of ScienceUniversity of Yaounde I

In this paper, following the phase portraits analysis, we investigate the integrability of a system which physically describes the transverse oscillation of an elastic beam under end-thrust. As a result, we find that this system actually comprises two families of travelling waves： the sub- and super-sonic periodic waves of positive- and negative- definite velocities, respectively, and the localized sub-sonic loop-shaped waves of positive-definite velocity. Expressing the energy-like of this system while depicting its phase portrait dynamics, we show that these multivaiued localized travelling waves appear as the boundary solutions to which the periodic travelling waves tend asymptotically

关键词： phase portraits elastic beam travelling waves

THE PROPERTIES OF MATRICES aI+βJ AND SOME RELATED PROBLEMS

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Acta Mathematicae Applicatae Sinica 1988年第4期 333-339页

作者：魏万迪阳本傅 Sichuan University teacher-training college of Chengdu

Let F Be a field,v(≥2)an integer,Ithe identity matrix of order v,and Jthe all-one matrix of order ***={aI+βJ,∈GL(F)|a,β∈F},and={C∈GL(F)|the row-sums and the column-sums of C are all equal}.In this paper,we study (1) the center and the centralizer of ,(2) the centralizer and the normalizer of when v=2,and (3) the orders of and the normalizer of.

关键词： Th J AND SOME RELATED PROBLEMS THE PROPERTIES OF MATRICES aI

Silica triflate as an efficient reagent for the solvent-free synthesis of coumarins

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Chinese Chemical Letters 2007年第8期18卷 909-911页

作者： Farhad Shirini Katayoun Marjani Hossein Taherpour Nahzomi Mohammad Ali Zolfigol Department of Chemistry College of ScienceGuilan UniversityRasht 41335Iran Faculty of Chemistry Teacher Training UniversityTehran 15614Iran Department of Chemistry College of ScienceBu-Ali Sina UniversityHamadan 65174Iran

Silica triflate, as a new silica-based reagent, can be used for the efficient synthesis of 4-substituted coumarins via a Pechmann reaction under solvent-free reaction conditions. All reactions were performed at 80 ℃ ... 详细信息

关键词： Silica triflate Coumarins Pechmann reaction Solvent-free reaction conditions Phenols

An Influence Maximization Algorithm Based on Improved K-Shell in Temporal Social Networks

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Computers, Materials & Continua 2023年第5期75卷 3111-3131页

作者： Wenlong Zhu Yu Miao Shuangshuang Yang Zuozheng Lian Lianhe Cui college of Computer and Control Engineering of Qiqihar University Qiqihar161006China college of teacher Education of Qiqihar University Qiqihar161006China

Influence maximization of temporal social networks(IMT)is a problem that aims to find the most influential set of nodes in the temporal network so that their information can be the most widely *** solve the IMT problem,we propose an influence maximization algorithm based on an improved K-shell method,namely improved K-shell in temporal social networks(KT).The algorithm takes into account the global and local structures of temporal social ***,to obtain the kernel value Ks of each node,in the global scope,it layers the network according to the temporal characteristic of nodes by improving the K-shell ***,in the local scope,the calculation method of comprehensive degree is proposed to weigh the influence of ***,the node with the highest comprehensive degree in each core layer is selected as the ***,the seed selection strategy of KT can easily lose some influential ***,by optimizing the seed selection strategy,this paper proposes an efficient heuristic algorithm called improved K-shell in temporal social networks for influence maximization(KTIM).According to the hierarchical distribution of cores,the algorithm adds nodes near the central core to the candidate seed *** then searches for seeds in the candidate seed set according to the comprehensive *** showthatKTIMis close to the best performing improved method for influence maximization of temporal graph(IMIT)algorithm in terms of effectiveness,but runs at least an order of magnitude faster than ***,considering the effectiveness and efficiency simultaneously in temporal social networks,the KTIM algorithm works better than other baseline algorithms.

关键词： Temporal social network influence maximization improved K-shell comprehensive degree

Equivalence Relation on the Set of Subsets of Zv and Enumeration of the Equivalence Classes

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数学进展 1988年第3期 326-327页

作者：魏万迪高绪洪阳本傅 Sichuan University Sichuan University teacher-training college of Chengdu

Motivated by the concept of equivalent cyclic difference sets on Zv（the residue ring modulo v）, we introduce a similar equivalence relation on the set of subsets of Zvas follows. Difinition Let D1and D2be two subset... 详细信息

关键词： Equivalence Relation on the Set of Subsets of Z_v and Enumeration of the Equivalence Classes