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21.
缺失功能性p35基因的苜蓿尺蠖核形多角体病毒(AcNPV)突变体(vΔP35K/pol+)感染草地夜蛾细胞(Sf9和Sf21)[1]及海灰翅夜蛾细胞(SL2)[2]时,引起细胞凋亡,从而使病毒的感染流产.我们发现海灰翅夜蛾核形多角体病毒(SlNPV)... 相似文献
22.
Radu Ioan Boţ Ioan Bogdan Hodrea Gert Wanka 《Nonlinear Analysis: Theory, Methods & Applications》2007
Considering a constrained fractional programming problem, within the present paper we present some necessary and sufficient conditions, which ensure that the optimal objective value of the considered problem is greater than or equal to a given real constant. The desired results are obtained using the Fenchel–Lagrange duality approach applied to an optimization problem with convex or difference of convex (DC) objective functions and finitely many convex constraints. These are obtained from the initial fractional programming problem using an idea due to Dinkelbach. We also show that our general results encompass as special cases some recently obtained Farkas-type results. 相似文献
23.
The first object of this paper is to introduce a new evolution equation for the characteristic function of the boundary Γ
of a Lipschitzian domain Ω in the N-dimensional Euclidean space under the influence of a smooth time-dependent velocity field. The originality of this equation is that the evolution takes place in an Lp-space with respect to the (N − 1)-Hausdorff measure. A second more speculative objective is to discuss how that equation can be relaxed to rougher velocity
fields via some weak formulation. A candidate is presented and some of the technical difficulties and open issues are discussed.
Continuity results in several metric topologies are also presented. The paper also specializes the results on the evolution
of the oriented distance function to initial sets with zero N-dimensional Lebesgue measure. 相似文献
24.
We show that, for two dimensional domains, Palais-Smale sequences for theH-equation functional or the harmonic map functional converge weakly (up to subsequences) to solutions of the equations. 相似文献
25.
Summary The problem of the construction of an equilibrium surface taking the surface tension into account leads to Laplace-Young equation which is a nonlinear elliptic free-boundary problem. In contrast to Orr et al. where an iterative technique is used for direct solution of the equation for problems with simple geometry, we propose here an alternative approach based on shape optimization techniques. The shape of the domain of the liquid is varied to attain the optimality condition. Using optimal control theory to derive expressions for the gradient, a numerical scheme is proposed and simple model problems are solved to validate the scheme. 相似文献
26.
Robert Hermann 《Acta Appl Math》1988,12(1):35-78
This paper will attempt to unify diverse material from physics and engineering in terms of differential forms on manifolds. A variational system will be defined by means of a scalar-valued differential form on a manifold and an ideal in the Grassmann algebra of differential forms on that manifold to serve as constraints. Two types of extremal submanifolds will be defined. The first-called the Euler-Lagrange extremals-will be defined by a method that is the generalization of the classical methods in the calculus of variations. The second—a generalization of a method used by Cartan in his treatise Leçons sur les invariants intégraux-will define extremals as integral submanifolds of an exterior differential system invariently attached to the variational system. As examples, the variational systems attached to string theories in Riemannian manifolds and Yang-Mills fields will be discussed from this differential form point of view. Finally, as application, the differential geometric properties and definition of energy will be presented from the differential form point of view.This work was supported by a grant from the Applied Mathematics program of the National Science Foundation. 相似文献
27.
Consider the variational integral
where Ω⊂ℝ
n
andp≥n≥2. H: (0, ∞)→[0, ∞) is a smooth convex function such that
. We approximateJ by a sequence of regularized functionalsJ
δ whose minimizers converge strongly to anJ-minimizing function and prove partial regularity results forJ
δ-minimizers. 相似文献
28.
Let: E M be a fiber bundle and let be an infinitesimal Lie transformation group acting onE. We announce various new results concerning the cohomology of the invariant variational bicomplex (
*,*
(J(E)), dH, dV) and the associated invariant Euler-Lagrange complex. As one application of our general theory, we completely solve the local invariant inverse problem of the calculus of variations for finite-dimensional infinitesimal Lie transformation groups. 相似文献
29.
Summary We study integral functionals of the formF(u, )=
f(u)dx, defined foru C1(;R
k), 49.gif" alt="sqsube" align="MIDDLE" BORDER="0">R
n
. The functionf is assumed to be polyconvex and to satisfy the inequalityf(A) c0¦499.gif" alt="phmmat" align="MIDDLE" BORDER="0">(A)¦ for a suitable constant c0 > 0, where 499.gif" alt="phmmat" align="MIDDLE" BORDER="0">(A) is then-vector whose components are the determinants of all minors of thek×n matrixA. We prove thatF is lower semicontinuous onC
1(;R
k) with respect to the strong topology ofL
1(;R
k). Then we consider the relaxed functional 497.gif" alt="Fscr" align="MIDDLE" BORDER="0">, defined as the greatest lower semicontinuous functional onL
1(;R
k
) which is less than or equal toF on C1(;R
k). For everyu BV(;R
k) we prove that 497.gif" alt="Fscr" align="MIDDLE" BORDER="0"> (u,)
f(u)dx+c0¦Dsu¦(), whereDu=u dx+Dsu is the Lebesgue decomposition of the Radon measureDu. Moreover, under suitable growth conditions onf, we show that 497.gif" alt="Fscr" align="MIDDLE" BORDER="0"> (u,)=
f(u)dx for everyu W1,p(;R
k), withp min{n,k}. We prove also that the functional 497.gif" alt="Fscr" align="MIDDLE" BORDER="0"> (u, ) can not be represented by an inte- gral for an arbitrary functionu BVloc(R
n;R
k). In fact, two examples show that, in general, the set function 497.gif" alt="Fscr" align="MIDDLE" BORDER="0"> (u, ) is not subadditive whenu BVloc(R
n;R
k), even ifu W
loc
1,p
(R
n;R
k) for everyp < min{n,k}. Finally, we examine in detail the properties of the functionsu BV(;R
k) such that 497.gif" alt="Fscr" align="MIDDLE" BORDER="0"> (u, )=
f(u)dx, particularly in the model casef(A)=¦499.gif" alt="phmmat" align="MIDDLE" BORDER="0">(A)¦. 相似文献
30.
We study hölder regularity of minimizers of the functional
, wherep(x) takes only two values and jumps across a Lipschitz surface. No restriction on the two values is imposed.This article was processed by the author using the Springer-Verlag TEX PJourlg macro package 1991. 相似文献