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91.
In economics, homothetic functions are production functions whose marginal technical rate of substitution is homogeneous of degree zero. Mathematically, a homothetic function is a function of the form f(x)=F(h(x1,…,xn)), where F is a monotonically increasing function and h is a homogeneous function of any degree d≠0. In this paper, we classify homothetic functions satisfying the homogeneous Monge–Ampère equation. Several applications to production models in economics will also be given. 相似文献
92.
《Operations Research Letters》2014,42(3):222-225
We discuss approximability and inapproximability in FPT-time for a large class of subset problems where a feasible solution is a subset of the input data. We introduce the notion of intersective approximability that generalizes the one of safe approximability introduced in Guo et al. (2011) and show strong parameterized inapproximability results for many of the subset problems handled. 相似文献
93.
Beatriz Margolis 《Numerical Functional Analysis & Optimization》2013,34(5-6):577-588
We develop a calculus structure in the Banach lattice introduced in a preceding paper, having in mind an approximation problem appearing in non-smooth optimization. We show that the essential results depend as much on the order structure as on the analytical one. 相似文献
94.
95.
The problem of deciding whether a graph manifold is finitely covered by a surface bundle over the circle is discussed in this
paper. A necessary and sufficient condition in term of the solutions of a certain matrix equation is obtained, as well as
a necessary condition which is easy to compute. Our results sharpen and extend the earlier results of J. Leucke-Y. Wu, W.
Neumann, and S. Wang-F. Yu in this topic.
Supported in part by NSFC 相似文献
96.
Lucia Caporaso 《Journal of Combinatorial Theory, Series A》2012,119(3):579-598
We prove the following “linkage” theorem: two p-regular graphs of the same genus can be obtained from one another by a finite alternating sequence of one-edge-contractions; moreover this preserves 3-edge-connectivity. We use the linkage theorem to prove that various moduli spaces of tropical curves are connected through codimension one. 相似文献
97.
An application to fuzzy economic systems of the fuzzy multi-valued functions theory elaborated by both of us in our previous papers is presented. First, stationary and dynamic fuzzy economic models are defined. Next the optimality of fuzzy trajectories of these models is introduced and investigated. 相似文献
98.
In this paper we apply computer algebra (Maple) techniques to calculate Jones polynomial of graphs of K(2,q)-Torus knots. For this purpose, a computer program was developed. When a positive integer q is given, the program calculate Jones polynomial of graph of K(2,q)-Torus knots. 相似文献
99.
David R. Wood 《Graphs and Combinatorics》2007,23(3):337-352
A clique is a set of pairwise adjacent vertices in a graph. We determine the maximum number of cliques in a graph for the following
graph classes: (1) graphs with n vertices and m edges; (2) graphs with n vertices, m edges, and maximum degree Δ; (3) d-degenerate graphs with n vertices and m edges; (4) planar graphs with n vertices and m edges; and (5) graphs with n vertices and no K5-minor or no K3,3-minor. For example, the maximum number of cliques in a planar graph with n vertices is 8(n − 2).
Research supported by a Marie Curie Fellowship of the European Community under contract 023865, and by the projects MCYT-FEDER
BFM2003-00368 and Gen. Cat 2001SGR00224. 相似文献
100.
轮图的广义Mycielski图的邻强边色数 总被引:3,自引:0,他引:3
设图 G(V,E)为简单图 ,V(Mn(G) ) |{ v0 1,v0 2 ,… ,v0 p;v11,v12 ,… ,v1p,… ,vn1,vn2 ,… ,vnp}E(Mn(G) ) =E(G)∪ { vijv(i+ 1) k|v0 jv0 k ∈ E(G) ,1≤ j,k≤ p ,i =0 ,1,… ,n - 1}称 Mn(G)为 G的 n广义 Mycielski图 ,n为自然数 .本文得到了轮的广义 Mycielski图的临强边色数 . 相似文献