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81.
刘富春 《江西师范大学学报(自然科学版)》1997,21(1):17-21,80
该文构作了一个liberal理论范Th讨论了liberal理论态射的一些性质,得到了Persistent函子了的一个刻划定理,同时也得到了F-free,F-generated,F-prime模型的一些结果。 相似文献
82.
Using the symplectic partitioned Runge–Kutta (PRK) method, we construct a new scheme for approximating the solution to infinite dimensional nonseparable Hamiltonian systems of Maxwell's equations for the first time. The scheme is obtained by discretizing the Maxwell's equations in the time direction based on symplectic PRK method, and then evaluating the equation in the spatial direction with a suitable finite difference approximation. Several numerical examples are presented to verify the efficiency of the scheme. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 相似文献
83.
In this article we carry on the study of the fundamental category (Goubault and Raussen, Dihomotopy as a tool in state space
analysis. In: Rajsbaum, S. (ed.) LATIN 2002: Theoretical Informatics. Lecture Notes in Computer Science, vol. 2286, Cancun,
Mexico, pp. 16–37, Springer, Berlin Heidelberg New York, 2002; Goubault, Homology, Homotopy Appl., 5(2): 95–136, 2003) of a partially ordered topological space (Nachbin, Topology and Order, Van Nostrand, Princeton, 1965; Johnstone, Stone Spaces, Cambridge University Press, Cambridge, MA, 1982), as arising in e.g. concurrency theory (Fajstrup et al., Theor. Comp. Sci. 357: 241–278, 2006), initiated in (Fajstrup et al., APCS, 12(1): 81–108, 2004). The “algebra” of dipaths modulo dihomotopy (the fundamental category) of such a po-space is essentially finite in a number
of situations. We give new definitions of the component category that are more tractable than the one of Fajstrup et al. (APCS,
12(1): 81–108, 2004), as well as give definitions of future and past component categories, related to the past and future models of Grandis (Theory
Appl. Categ., 15(4): 95–146, 2005). The component category is defined as a category of fractions, but it can be shown to be equivalent to a quotient category,
much easier to portray. A van Kampen theorem is known to be available on fundamental categories (Grandis, Cahiers Topologie
Géom. Différentielle Catég., 44: 281–316, 2003; Goubault, Homology, Homotopy Appl., 5(2): 95–136, 2003), we show in this paper a similar theorem for component categories (conjectured in Fajstrup et al. (APCS, 12(1): 81–108,
2004). This proves useful for inductively computing the component category in some circumstances, for instance, in the case of
simple PV mutual exclusion models (Goubault and Haucourt, A practical application of geometric semantics to static analysis
of concurrent programs. In: Abadi, M., de Alfaro, L. (eds.) CONCUR 2005 – Concurrency Theory: 16th International Conference,
San Francisco, USA, August 23–26. Lecture Notes in Computer Science, vol. 3653, pp. 503–517, Springer, Berlin Heidelberg New
York, 2005), corresponding to partially ordered subspaces of R
n
minus isothetic hyperrectangles. In this last case again, we conjecture (and give some hints) that component categories enjoy
some nice adjunction relations directly with the fundamental category.
相似文献
84.
85.
Margarida Mendes Lopes Rita Pardini Sofia Tirabassi 《Mathematische Nachrichten》2023,296(10):4739-4744
Kawamata has shown that the quasi-Albanese map of a quasi-projective variety with log-irregularity equal to the dimension and log-Kodaira dimension 0 is birational. In this note, we show that under these hypotheses the quasi-Albanese map is proper in codimension 1 as conjectured by Iitaka. 相似文献
86.
Dana Gheorghe 《Journal of Mathematical Analysis and Applications》2009,354(1):273-285
Using some techniques of perturbation theory for quotient morphisms between Banach spaces we obtain necessary and sufficient conditions for the stability of the topological index of a q-open quotient morphism under small (with respect to the gap topology) perturbations with quotient morphisms. As an application we obtain necessary and sufficient conditions for the stability of the topological index of an open linear relation with closed multivalued part between normed spaces under small perturbations with linear relations. 相似文献
87.
88.
Stochastic partitioned averaged vector field methods for stochastic differential equations with a conserved quantity 下载免费PDF全文
In this paper, stochastic differential equations in the Stratonovich sense with a conserved quantity are considered. A stochastic partitioned averaged vector field method is proposed and analyzed. We prove this numerical method is able to preserve the conserved quantity of the original system. Then the convergence analysis is carried out in detail and we derive the method is convergent with order $1$ in the mean-square sense. Finally some numerical examples are reported to verify the effectiveness and flexibility of the proposed method. 相似文献
89.
长江外贸集装箱运量预测和码头装卸工艺优选 总被引:1,自引:0,他引:1
本文利用新陈代谢GM(1,1)模型、二次指数滑动平均法、计量经济学模型3种预测模型对上海港进行了外贸集装箱吞吐量的预测,并结合考虑长江各主要港口在共同航线上的运量分配及航线运量占该港吞吐量的比重,对各港口进行了外贸集装箱吞吐量和主要航线运量预测。然后,运用多目标决策理论中的线性分配法与层次分析法,分析了不同运量水平下港口装卸工艺系统的优选问题,并利用外贸集装箱的预测结果,得到了这些港口装卸工艺的优 相似文献
90.