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941.
Let T be a set of tasks. Each task has a non-negative processing time and a deadline. The problem of determining whether or not there is a schedule of the tasks in T such that a single machine can finish processing each of them before its deadline is polynomially solvable. We prove that counting the number of schedules satisfying this condition is #P-complete. 相似文献
942.
Cinzia Bisi 《Journal of Mathematical Analysis and Applications》2009,350(1):327-332
We investigate the dynamical behaviour of a holomorphic map on an f-invariant subset C of U, where . We study two cases: when U is an open, connected and polynomially convex subset of Ck and C?U, closed in U, and when ∂U has a p.s.h. barrier at each of its points and C is not relatively compact in U. In the second part of the paper, we prove a Birkhoff's type theorem for holomorphic maps in several complex variables, i.e. given an injective holomorphic map f, defined in a neighborhood of , with U star-shaped and f(U) a Runge domain, we prove the existence of a unique, forward invariant, maximal, compact and connected subset of which touches ∂U. 相似文献
943.
944.
Junmin Yang Valery G. Romanovski 《Journal of Mathematical Analysis and Applications》2010,366(1):242-255
In this paper we first give some general theorems on the limit cycle bifurcation for near-Hamiltonian systems near a double homoclinic loop or a center as a preliminary. Then we use these theorems to study some polynomial Liénard systems with perturbations and give new lower bounds for the maximal number of limit cycles of these systems. 相似文献
945.
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947.
《Journal of Pure and Applied Algebra》2023,227(8):107345
Until recently, the only known examples of non-injective polynomial local diffeomorphisms of the plane were the Pinchuk maps discovered in 1994. These maps have the form , where p is a fixed polynomial of degree 10, and q satisfies certain relation. The lowest possible degree of q in a Pinchuk map is 25. In 2021, with the same p of a Pinchuk map, another example was given with q of degree 15. Aiming to find different examples, with the first components having lower degrees, we look for polynomials of degree less than or equal to 9 sharing some properties with the polynomial p of a Pinchuk map. We find precisely one polynomial of degree 7 and some ones of degree 9. By using one of the polynomials of degree 9 in the first component we construct a non-injective polynomial local diffeomorphism of the plane, with degree 15. 相似文献
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