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991.
In this paper we establish an explicit relation between the growth type of general entire solutions to the generalized Cauchy-Riemann
system in
\mathbbRn+1{\mathbb{R}^{n+1}}
and their Taylor coefficients. This formula then enables us to compute the growth type of some higher dimensional generalizations
of the trigonometric and special functions that are null-solutions to this system. 相似文献
992.
Commutators of singular integrals on spaces of homogeneous type 总被引:1,自引:0,他引:1
In this work we prove some sharp weighted inequalities on spaces of homogeneous type for the higher order commutators of singular
integrals introduced by R. Coifman, R. Rochberg and G. Weiss in Factorization theorems for Hardy spaces in several variables,
Ann. Math. 103 (1976), 611–635. As a corollary, we obtain that these operators are bounded on L
p
(w) when w belongs to the Muckenhoupt’s class A
p
, p > 1. In addition, as an important tool in order to get our main result, we prove a weighted Fefferman-Stein type inequality
on spaces of homogeneous type, which we have not found previously in the literature. 相似文献
993.
Exploring new directions for research in problem structuring methods: on the role of cognitive style
Prior research has argued that cognitive style can have a significant impact on group decision making. In addition, several scholars have proposed that cognitive style can play a key role in the design and use of group decision support systems. However, cognitive style has not received a great deal of attention in the problem structuring methods (PSMs) community. This is surprising, given that PSMs are specifically developed to support a group in their decision making. The purpose of this paper is thus to examine the significance of cognitive style within PSMs. The paper identifies and explores the role of four different cognitive style functions in problem structuring interventions. This analysis is carried out by focusing on the different tasks embedded within a group process supported by PSMs. Implications for the research and practice of PSMs are then discussed. 相似文献
994.
Motivated by Gauss's first proof of the Fundamental Theorem of Algebra, we study the topology of harmonic algebraic curves.
By the maximum principle, a harmonic curve has no bounded components; its topology is determined by the combinatorial data
of a noncrossing matching. Similarly, every complex polynomial gives rise to a related combinatorial object that we call a
basketball, consisting of a pair of noncrossing matchings satisfying one additional constraint. We prove that every noncrossing
matching arises from some harmonic curve, and deduce from this that every basketball arises from some polynomial. 相似文献
995.
Let C be a family of n different unit circles in the plane. We show that C determines at least n - c intersection points,
where c is the number of connected components in ∪C ∈ CC. This proves a conjecture of A. Bezdek. 相似文献
996.
Discrete-time GI/Geo/1 queue with multiple working vacations 总被引:2,自引:0,他引:2
Consider the discrete time GI/Geo/1 queue with working vacations under EAS and LAS schemes. The server takes the original
work at the lower rate rather than completely stopping during the vacation period. Using the matrix-geometric solution method,
we obtain the steady-state distribution of the number of customers in the system and present the stochastic decomposition
property of the queue length. Furthermore, we find and verify the closed property of conditional probability for negative
binomial distributions. Using such property, we obtain the specific expression for the steady-state distribution of the waiting
time and explain its two conditional stochastic decomposition structures. Finally, two special models are presented.
相似文献
997.
This study uses data envelopment analysis to analyse the efficiency of educational systems in 31 countries. This type of evaluation is of interest both when formulating a model for analysis and when applying such a model empirically. The efficiency of an educational system must take into account the students' economic and social background, as this is an environmental factor that decisively influences their performance. This is a highly important aspect and so we propose a specific evaluative process for it. Secondly, we evaluate the efficiency of educational systems in different countries, an analysis that has few forerunners since the majority of previous research has focused on analysing a single country. The results suggest that, in general, the most efficient management of educational systems can be found in those countries with a Communist past. They also suggest that there is a series of developed countries, which, judging by the results obtained, could increase their students' performance with even fewer resources than those currently allocated to their educational systems. 相似文献
998.
O Berman 《The Journal of the Operational Research Society》2007,58(10):1396-1396
999.
Paolo Battocchio Francesco Menoncin Olivier Scaillet 《Annals of Operations Research》2007,152(1):141-165
In a financial market with one riskless asset and n risky assets whose prices are lognormal, we solve in a closed form the problem of a pension fund maximizing the expected
CRRA utility of its surplus till the (stochastic) death time of a representative agent. We consider a unique asset allocation
problem for both accumulation and decumulation phases. The optimal investment in the risky assets must decrease during the
first phase and increase during the second one. We accordingly suggest it is not optimal to manage the two phases separately,
and outsourcing of allocation decisions should be avoided in both phases.
JEL: G23, G11
MSC 2000: 62P05, 91B28, 91B30, 91B70, 93E20 相似文献
1000.
K. Ren Z.Y. Li X. Ren B. Cheng D. Zhang 《Applied Physics A: Materials Science & Processing》2007,87(2):181-185
This paper describes a simple hydrothermal procedure for high-yield synthesis of single-crystalline ZnO hexagonal nanoplates in a surfactant-free system at 70 °C. The structures and morphologies of the synthesized ZnO nanoplates are derived from characterisation by X-ray diffraction, and scanning and transmission electron microscopy. Their optical properties are recorded by Raman and photoluminescence spectroscopy. These ZnO hexagonal nanoplates exhibit the enhanced photocatalytic activity of phenol photodecomposition, suggesting that they could be served as an active system for the treatment of the waste water, in addition to their common applications. PACS 81.10.Dn; 61.10.Nz; 68.37.Hk; 78.55.Hx 相似文献