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1.
An applied cell mapping method for optimal control problems 总被引:1,自引:0,他引:1
W. H. Zhu 《Journal of Optimization Theory and Applications》1989,60(3):485-500
From the application point of view, a series of modifications are proposed for the cell mapping method discussed in Ref. 1 for the optimal control analysis of dynamical systems. The cell order around the target set is rearranged. A set of common discriminate principles is used for the selection of the optimal one among competing control strategies of the same cost. Inequality constraints of the system are taken into account. The number of elements in the set of allowable time intervals is not prescribed, but left open. These modifications seem to make the cell mapping method more efficient for analyzing feedback systems and for obtaining their global optimal control information. The algorithms presented in this paper could broaden the application of the cell mapping approach of Ref. 1 to a wider class of engineering problems. 相似文献
2.
We establish the optimal asymptotic decay rate of per-session queue length tail distributions for a two-queue system where
a single constant rate server serves the two queues using the Generalized Processor Sharing (GPS) scheduling discipline. The
result is obtained using the sample-path large deviation principle and has implications in call admission control for high-speed
communication networks.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
3.
LetB
1
be a ball of radiusr
1
inS
n
(ℍn), and letB
0
be a smaller ball of radiusr
0
such thatB
0
⊂B
1
. ForS
n
we considerr
1
π. Let u be a solution of the problem- δm = 1 in Ω :=B
1
/B
0
vanishing on the boundary. It is shown that the associated functionalJ (Ω) is minimal if and only if the balls are concentric. It is also shown that the first Dirichlet eigenvalue of the Laplacian
on Ω is maximal if and only if the balls are concentric. 相似文献
4.
We isolate several classes of stationary sets of [k]ωand investigate implications among them. Under a large cardinal assumption, we prove a structure theorem for stationary sets. 相似文献
5.
We introduce some relative versions of star selection principles first considered in [5], [11]. Some of the work extends results
from [4], [5] and gives some examples.
相似文献
6.
Steven J. Sepanski 《Journal of Theoretical Probability》1997,10(4):1053-1063
For independent identically distributed random vectors belonging to the generalized Domain of Attraction of the multivariate normal law, we define two partial sum processes analogous to that of Donsker's Theorem. We prove that each converges in distribution to a Brownian Motion in the space of continuous functions. One process uses nonrandom operator normalization, and the other is a studentization of the first, using normalization by the empirical covariance operator. 相似文献
7.
Qiji J. Zhu 《Set-Valued Analysis》1998,6(2):171-185
Several different basic tools are used for studying subdifferentials. They are a nonlocal fuzzy sum rule in (Borwein et al., 1996; Zhu, 1996), a multidirectional mean value theorem in (Clarke and Ledyaev, 1994; Clarke et al., 1998), local fuzzy sum rules in (Ioffe, 1984, 1990) and an extremal principle in (Kruger and Mordukhovich, 1980; Mordukhovich, 1976, 1980, 1994). We show that all these basic results are equivalent and discuss some interesting consequences of this equivalence. 相似文献
8.
The structural and magnetic properties of a new ternary Ir-Mn-Ge phase, Mn3IrGe, as well as the solid solution Mn3Ir(Si1−xGex), 0?x?1, have been investigated by means of X-ray and neutron powder diffraction, magnetization measurements and first principles calculations. The crystal structure is cubic, of the AlAu4-type (an ordered form of the β-Mn structure), Z=4, space group P213, and the unit-cell dimension varies linearly with the silicon content. For all compositions, antiferromagnetic ordering is found below a critical temperature of about 225 K. The magnetic structure is noncollinear, as a result of frustrated magnetic interactions on a triangular network of Mn atoms, on which the moments rotate 120° around the triangle axes. The magnitude of the magnetic moment at 10 K is 3.39(4) μB for Mn3IrGe. The theoretical calculations reproduce with very good accuracy the magnitudes as well as the directions of the experimentally observed magnetic moments. 相似文献
9.
《Surface and interface analysis : SIA》2003,35(10):835-841
We have examined the optimal interface structure, ideal work of adhesion and bonding character of polar Ti(110)/TiN(111) interfaces by first‐principles density‐functional plane‐wave pseudopotential calculations. Both Ti‐ and N‐terminated interfaces, including six different interface structures, were calculated. The interface structure for each termination, continuing the TiN crystal structure across the interface, has the largest work of adhesion. Although both terminations yield substantial adhesion energies in the range 3–7 J m?2, the N‐terminated interface is ~4 J m?2 stronger than the Ti‐terminated interface. Analysis of the interfacial electronic structure shows that the Ti‐terminated interface is a mixed strong, metallic and weak covalent character, whereas the N‐terminated interface is a polar covalent bond similar to the Ti/TiC interface. Further study of the separation of the optimal interface shows that the cleavages will never fracture at the interface due to the strong bonding, which is consistent with the experimental results. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
10.
A. S. Said 《Journal of separation science》1979,2(2):63-67
The theory of composite chromatographic columns has been re-examined and general equations relating their efficiency to those of individual columns were derived. The derivations were based on elementary principles without reference to the principle of variance additivity. Derived also, were general equations for the efficiency of columns with continuously varying diameters, HETP and other properties from which formulae for special cases of practical interest were deduced. An example comparing the efficiencies of two columns, one conical and the other composite was given. The calculations show clearly that the conical column is superior in efficiency for the same total length and total retention volume. 相似文献