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971.
L.M.GrafiaDrummond A.N.Iusem B.F.Svaiter 《应用数学学报(英文版)》2003,19(3):371-386
We develop first order optimality conditions for constrained vector optimization. The partial orders for the objective and the constraints are induced by closed and convex cones with nonempty interior. After presenting some well known existence results for these problems, based on a scalarization approach, we establish necessity of the optimality conditions under a Slater-like constraint qualification, and then sufficiency for the K-convex case. We present two alternative sets of optimality conditions, with the same properties in connection with necessity and sufficiency, but which are different with respect to the dimension of the spaces to which the dual multipliers belong. We introduce a duality scheme, with a point-to-set dual objective, for which strong duality holds. Some examples and open problems for future research are also presented, 相似文献
972.
Let D =(V,E)be a primitive digraph.The vertex exponent of D at a vertex v∈V,denoted by exPD(V),is the least integer p such that there is a v→u walk of length p for each u∈V.Following Brualdi and Liu,we order the vertices of D so that exPD(v_1)≤exPD(v_2)≤…≤exPD(v_n).Then exPD(v_k)is called the k- point exponent of D and is denoted by exP_D(k),1≤k≤n.In this paper we define e(n,k):=max{exp_D(k)|D∈PD(n,2)} and E(n,k):= {expD(k)|D∈PD(n,2)},where PD(n,2)is the set of all primitive digraphs of order n with girth 2.We completely determine e(n,k)and E(n,k)for all n,k with n≥3 and 1≤k≤n. 相似文献
973.
974.
一种新的可分凸二次规划的不可行内点算法 总被引:3,自引:0,他引:3
本文对可分凸二次规划提出了一个新的不可行内点算法 ,证明了该算法是一个多项式时间算法 ,并将迭代复杂性界降至O(nL) . 相似文献
975.
ROOS Guy 《中国科学A辑(英文版)》2006,(9)
We study the complete Kahler-Einstein metric of a Hartogs domainΩbuilt on an irreducible bounded symmetric domainΩ, using a power Nμof the generic norm ofΩ.The generating function of the Kahler-Einstein metric satisfies a complex Monge-Ampere equation with a boundary condition. The domainΩis in general not homogeneous, but it has a subgroup of automorphisms, the orbits of which are parameterized by X∈[0,1[. This allows us to reduce the Monge-Ampere equation to an ordinary differential equation with a limit condition. This equation can be explicitly solved for a special valueμ0 ofμ.. We work out the details for the two exceptional symmetric domains. The special valueμ0 seems also to be significant for the properties of other invariant metrics like the Bergman metric; a conjecture is stated, which is proved for the exceptional domains. 相似文献
976.
耿献国 《高校应用数学学报(A辑)》1989,4(4):494-497
本文导出二维Sawada-Kotera方程的Darboux变换和B(?)cklund变换。作为一个特例,讨论了一维Sawada-Kotera方程并求出了两方程的孤子解。 相似文献
977.
Jiang Qian Yuehong Tang 《高等学校计算数学学报(英文版)》2006,15(4):320-335
The recurrence algorithm is given for the calculation of NUAH B-splines in the space Sn 1 = span{sinh t, cosh t,tn-3,...,t2.t, 1} (n≥3). The case of NUAH B-spline bases of low order with multiple knot sequences is studied. The limiting cases of UAH B-splines are recovered when shape parameters a's→0 and ∞. Then the corresponding NUAH B-spline curve is defined and its main properties such as shape-preserving properties are investigated. 相似文献
978.
宁刚 《数学的实践与认识》2006,36(1):224-226
证明了如下结果:设g∶H→H,C H是非空开的g-凸集,g(C)是凸集,f是C上的上半连续函数且存在α∈(0,1),使得f(αg(x)+(1-α)g(y))m ax{f。g(x),f。g(y)},x,y∈C,则f为C上的g-拟凸函数. 相似文献
979.
We introduce the tracial limit A = (t4) limn→n∞ (An,pn) and show that if K0(An) has ordered relation, K0(A) has ordered relation naturally. In the case that A is simple and K0(An) is weakly unperforated for every n, K0(A) is weakly unperforated too. Furthermore, the Riesz interpolation property of K0(An) can be transmitted to K0(A). 相似文献
980.
FATOU PROPERTY ON HARMONIC MAPS FROM COMPLETE MANIFOLDS WITH NONNEGATIVE CURVATURE AT INFINITY INTO CONVEX BALLS 总被引:3,自引:0,他引:3
Yang Yihu 《数学年刊B辑(英文版)》1995,16(3):341-350
FATOUPROPERTYONHARMONICMAPSFROMCOMPLETEMANIFOLDSWITHNONNEGATIVECURVATUREATINFINITYINTOCONVEXBALLS¥YANGYIHUAbstract:Theauthorc... 相似文献