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141.
142.
Jiří Adámek Horst Herrlich Jiří Rosický Walter Tholen 《Applied Categorical Structures》2002,10(3):237-249
Weak factorization systems, important in homotopy theory, are related to injective objects in comma-categories. Our main result is that full functors and topological functors form a weak factorization system in the category of small categories, and that this is not cofibrantly generated. We also present a weak factorization system on the category of posets which is not cofibrantly generated. No such weak factorization systems were known until recently. This answers an open problem posed by M. Hovey. 相似文献
143.
Kari Eloranta 《Journal of statistical physics》1994,76(5-6):1377-1398
We investigate the dynamics of ensembles of diffusive defects in one-dimensional deterministic cellular automata. The work builds on earlier results on individual random walks in cellular automata. Here we give a natural condition guaranteeing diffusive behavior also in the presence of other defects. Simple branching and birth mechanisms are introduced and prototype classes of cellular automata exhibiting weakly interacting walks capable of annihilation and coalescence are studied. Their equilibrium behavior is also characterized. The design principles of cellular automata with desired diffusive interaction properties become transparent from this analysis. 相似文献
144.
郭伟平 《数学物理学报(A辑)》2007,27(5):907-914
在非紧集上证明了两类多值算子的 Hartman-Stampacchia 变分不等式, 作为应用, 讨论了多值算子的相补问题. 相似文献
145.
New minimax inequality with applications to existence theorems of equilibrium points 总被引:4,自引:0,他引:4
A new minimax inequality is proved on a set which is the union of an increasing sequence of compact convex sets in a topological vector space. As applications, several existence theorems of equilibrium points for different games are obtained.The authors would like to thank the referees for their helpful suggestions. 相似文献
146.
ON THE EXISTENCE OF ZERO POINTS OF A CONTINUOUS FUNCTION 总被引:3,自引:1,他引:2
J.M. SorianoDepartamento de Andlisis Matematico Facultad de Matemdticas Universidad de Sevilla Aptdo. Sevilla Spain 《数学物理学报(B辑英文版)》2002,22(2)
IPreliminarlesTheee。etOOk totot比OO。stsllCCdCSdO‘lOll‘。山OOqll时1OO/(。)=。,SS山 SFSSdPoint Theorems[‘’,”],Degree Theory【9,15].In general these are used when f aPPlies a set ora space on itself.Cm眈inn眈ion Methods can be used to test the existence ofa solution whenf pplies a set or a sp。e on it咖‘-’,”-“l,or aPPlies a set or sP。m another sP。,s。M see here.wrthermore,contlnuulon methods pve us the exlstence ofcurves wb讪 can beused to CalCttlue the Sdutionsl6… 相似文献
147.
O. I. Mokhov 《Theoretical and Mathematical Physics》2007,152(2):1183-1190
We prove that the associativity equations of two-dimensional topological quantum field theories are very natural reductions
of the fundamental nonlinear equations of the theory of submanifolds in pseudo-Euclidean spaces and give a natural class of
flat torsionless potential submanifolds. We show that all flat torsionless potential submanifolds in pseudo-Euclidean spaces bear natural structures
of Frobenius algebras on their tangent spaces. These Frobenius structures are generated by the corresponding flat first fundamental
form and the set of the second fundamental forms of the submanifolds (in fact, the structural constants are given by the set
of the Weingarten operators of the submanifolds). We prove that each N-dimensional Frobenius manifold can be locally represented
as a flat torsionless potential submanifold in a 2N-dimensional pseudo-Euclidean space. By our construction, this submanifold
is uniquely determined up to motions. Moreover, we consider a nonlinear system that is a natural generalization of the associativity
equations, namely, the system describing all flat torsionless submanifolds in pseudo-Euclidean spaces, and prove that this
system is integrable by the inverse scattering method.
To the memory of my wonderful mother Maya Nikolayevna Mokhova (4 May 1926–12 September 2006)
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 152, No. 2, pp. 368–376, August, 2007. 相似文献
148.
为了阐明芳香性及磁性原因,用Aihara提出的TRE概念计算了 ,苯并环丁二烯和戊搭烯等烃的共振能,环共振能和环电流.计算结果表明 因有正共振能具有芳香性并产生反磁性环电流,而苯并环丁二烯和戊塔烯因有负共振能具有反芳香性并产生顺磁性环电流. 相似文献
149.
本文研究了具有鉴相特性g()=((1+k)sin())/(1+kcos())的三阶锁相环路方程奇点的拓扑结构. 相似文献
150.
S. Verwulgen 《Applied Categorical Structures》2007,15(5-6):647-653
It is well-known (see Semadeni, Queen Pap. Pure Appl. Math., 33:1–98, 1973 and Pumplün and Röhrl, Commun. Algebra, 12(8):953–1019, 1984, 1985) that the embedding of vector spaces into the category of absolutely convex modules is reflective. As we will show, under a separatedness condition on these modules it is at the same time coreflective. This is a peculiar situation, see Kannan, Math. Ann., 195:168–174, (1972) and Hu $\textrm {\u{s}}It is well-known (see Semadeni, Queen Pap. Pure Appl. Math., 33:1–98, 1973 and Pumplün and R?hrl, Commun. Algebra, 12(8):953–1019, 1984, 1985) that the embedding of vector spaces into the category of absolutely convex modules is reflective. As we will show, under
a separatedness condition on these modules it is at the same time coreflective. This is a peculiar situation, see Kannan,
Math. Ann., 195:168–174, (1972) and Huek, Reflexive and coreflexive subcategories of unif and top, Seminar Uniform Spaces, Prague, 113–126, (1973), but we do find it also in the embedding (Lowen, Approach Spaces: The Missing Link in the Topology-Uniformity-Metric Triad. Oxford Mathematical Monographs, Oxford
University Press, London, UK, 1997) and, by extension, in the embedding (see Lowen and Verwulgen, Houst. J. Math, 30(4):1127–1142, 2004, and Sioen and Verwulgen, Appl. Gen. Topol., 4(2):263–279, 2003. We demonstrate that, in this setting, by duality arguments, absolutely convex modules are indeed the numerical counterpart
of vector spaces. All these, at first sight unrelated facts, are comprised in the commutative scheme below with natural dualisation
functors and their left adjoints.
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