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961.
We study the structure of a foliation of high codimension which
admits a transverse foliation.
We introduce four families of open saturated sets. These open
sets have a simple characterization and allow us to establish a structure
theorem as in codimension 1. 相似文献
962.
In this paper, we consider the following singular nonlinear problem
where A is a positive continuous function on (0,1), q is a nonnegative measurable function on [0,1] and f is a nonnegative regular function on (0,1)×(0,).We suppose that
0
1
dt/A(t)< and 0<
0
1
A(t)q(t) dt<. Then we prove the existence and the uniqueness of a positive solution of this problem (P).Our approach is based on the use of the Green's function and the Schauder's fixed point theorem. 相似文献
963.
Habib Salehi 《Journal of Mathematical Analysis and Applications》1973,41(3):575-582
Helley's 1st and 2nd theorems for trace class-valued distributions are established. Using these theorems the concept of spectrum for an infinite dimensional nonstationary stochastic process is introduced, and a law of large numbers for processes which admit a spectrum is obtained. 相似文献
964.
N-Free posets have recently taken some importance and motivated many studies. This class of posets introduced by Grillet [8] and Heuchenne [11] are very related to another important class of posets, namely the series-parallel posets, introduced by Lawler [12] and studied by Valdes et al. [21]. This paper shows how N-free posets can be considered as generalizations of series-parallel posets, by giving a recursive construction of N-free posets. Furthermore we propose a linear time algorithm to recognize and decompose any N-free poset. This yields some very naturel problems, namely: which are the properties(such as linear time algorithm for some invariant) of series-parallel posets that are kept for N-free posets? 相似文献
965.
A halogen anion sensor based on the hydrophobic entrapment of a fluorescent probe in silica sol-gel thin films 总被引:2,自引:0,他引:2
A halogen anion (Cl−, Br−, I−) sensor has been designed, based on the entrapment of a fluorescent molecule in a sol-gel silica film deposited on a glass substrate. A key factor is the use of the newly synthesized hydrophobic fluorophore, N-dodecyl-6-methoxyquinolinium, so as to avoid the problem of leaching. This probe allows detection and measurement of chloride concentrations in the physiological range (100 mM) coupled with a response time less than 1 s. The fluorescence quenching data are fitted to a model which assumes two quenching sites. 相似文献
966.
Equality between the interval dimensions of a poset and its MacNeille completion, announced in [7], has been obtained by the authors as a byproduct of their study of Galois lattices in [8]. The purpose of this note is to give a direct proof, similar to the classical proof of Baker's result stating that the dimension (in the Dushnik-Miller sense) of a poset and its MacNeille completion are the same.Supported by French PRC Math-Info. 相似文献
967.
968.
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970.