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11.
12.
Despite slow ongoing progress in increasing the representation of women in academia, women remain significantly under-represented at senior levels, in particular in the natural sciences and engineering. Not infrequently, this is downplayed by bringing forth arguments such as inherent biological differences between genders, that current policies are adequate to address the issue, or by deflecting this as being “not my problem” among other examples. In this piece we present scientific evidence that counters these claims, as well as a best-practice example, Genie, from Chalmers University of Technology, where one of the authors is currently employed. We also highlight particular challenges caused by the current COVID-19 pandemic. Finally, we conclude by proposing some possible solutions to the situation and emphasize that we need to all do our part, to ensure that the next generation of academics experience a more diverse, inclusive, and equitable working environment.  相似文献   
13.
In this paper, we present several parametric duality results under various generalized ( α,η,ρ )-V- invexity assumptions for a semiinfinite multiobjective fractional programming problem.  相似文献   
14.
In this paper we give corrections to our paper on an augmented Lagrangian type algorithm for strictly convex quadratic programming problems with equality constraints.  相似文献   
15.
Neighboring extremals of dynamic optimization problems with path equality constraints and with an unknown parameter vector are considered in this paper. With some simplifications, the problem is reduced to solving a linear, time-varying two-point boundary-value problem with integral path equality constraints. A modified backward sweep method is used to solve this problem. Two example problems are solved to illustrate the validity and usefulness of the solution technique. This research was supported in part by the National Aeronautics and Space Administration under NASA Grant No. NCC-2-106. The author is indebted to Professor A. E. Bryson, Jr., Department of Aeronautics and Astronautics, Stanford University, for many stimulating discussions.  相似文献   
16.
The main result of this paper is the following theorem. Suppose thatτ(n) = ∑ d|n l and the arithmetical functionF satisfies the following conditions:
1)  the functionF is multiplicative;
2)  ifF(n) = ∑ d|n f(d), then there exists an α>0 such that the relationf(n)=O(n −α) holds asn→∞.
Then there exist constantsA 1,A 2, andA 3 such that for any fixed \g3\s>0 the following relation holds:
. Moreover, if for any primep the inequality \vbf(p)\vb\s<1 holds and the functionF is strongly multiplicative, thenA 1\s>0. Translated fromMatematicheskie Zametki, Vol. 68, No. 3, pp. 429–438, September, 2000.  相似文献   
17.
We consider a distance-regular graph with diameter d 3 and eigenvalues k = 0 > 1 > ... > d . We show the intersection numbers a 1, b 1 satisfy
We say is tight whenever is not bipartite, and equality holds above. We characterize the tight property in a number of ways. For example, we show is tight if and only if the intersection numbers are given by certain rational expressions involving d independent parameters. We show is tight if and only if a 1 0, a d = 0, and is 1-homogeneous in the sense of Nomura. We show is tight if and only if each local graph is connected strongly-regular, with nontrivial eigenvalues –1 – b 1(1 + 1)–1 and –1 – b 1(1 + d )–1. Three infinite families and nine sporadic examples of tight distance-regular graphs are given.  相似文献   
18.
A technique for maintaining the positive definiteness of the matrices in the quasi-Newton version of the SQP algorithm is proposed. In our algorithm, matrices approximating the Hessian of the augmented Lagrangian are updated. The positive definiteness of these matrices in the space tangent to the constraint manifold is ensured by a so-called piecewise line-search technique, while their positive definiteness in a complementary subspace is obtained by setting the augmentation parameter. In our experiment, the combination of these two ideas leads to a new algorithm that turns out to be more robust and often improves the results obtained with other approaches.  相似文献   
19.
§ 1  IntroductionIn this paper we study the following nonlinear equality constrained optimization prob-lem:minimize f(x) ,subjectto h(x) =0 ,(P)where h(x) =(h1 (x) ,h2 (x) ,...,hm(x) ) T,f and hi(i=1 ,2 ,...,m) are Rn→R twice conti-nously differentiable(m≤n) .Many authors have studied the problem(P) with trustregion method(see,references[1~ 3 ] ) .These methods have the same property:to enforce strict monotonicity for meritfunction at every iteration.Paper[4 ] shows thatstrictmonotonic …  相似文献   
20.
詹华英 《数学学报》2008,51(3):567-570
本文的主要结论是给出了一个更广泛形式的Mazur-Ulam定理.讨论的对象是实的赋准范空间,满等距算子被减弱成其像空间构成一个加法子群的算子.最后给出的推论推广了Skof的一个结果.  相似文献   
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