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1.
Sze-Man Tse 《Annals of the Institute of Statistical Mathematics》2006,58(4):675-686
In this paper, we consider a nonparametric estimator of the Lorenz curve and Gini index when the data are subjected to random
left truncation and right censorship. Strong Gaussian approximations for the associated Lorenz process are established under
appropriate assumptions. A law of the iterated logarithm for the Lorenz curve is also derived. Lastly, we obtain a central
limit theorem for the corresponding Gini index. 相似文献
2.
We prove that the Heighway dragon is a countable union of closed geometrically similar disk-like planar sets which intersect
each other in a linear order: any two of them intersect at no more than one cut point and for any three disks there exist
at least two with an empty intersection. Consequently, the interior of the Heighway dragon is a countable union of disjoint
open disk-like planar sets. We determine all the cut points of the dragon and show that each disk-like subset between two
cut points is a graph self-similar set defined by a graph-directed iterated function system consisting of four seed sets.
Our results describe a fairly complete picture of the topological and geometric structure of the Heighway dragon. 相似文献
3.
With a new titanium imineenolato complex, ethylene is polymerized in an unprecedented living fashion affording a polymer with a high molecular weight (Mn > 10(5) g mol-1) and an extremely narrow distribution (Mw/Mn 1.01) at the same time; the living character is also retained even at an elevated temperature of 75 degrees C, and blockcopolymers are accessible. 相似文献
4.
We study the topological structure of connected self-similar tiles in defined by injective contractions satisfying the open set condition. We emphasize on tiles each of whose interior consists of either finitely or infinitely many components. In the former case, we show in particular that the closure of some component is a topological disk. In the latter case we show that the closure of each component is a locally connected continuum. We introduce the finite tail and infinite replication properties and show that under these assumptions the closure of each component is a disk. As an application we prove that the closure of each component of the interior of the Lévy dragon is a disk. 相似文献
5.
We extend both the weak separation condition and the finite type condition to include finite iterated function systems (IFSs)
of injective C
1 conformal contractions on compact subsets of
\mathbbRd{{\mathbb{R}}^d} . For conformal IFSs satisfying the bounded distortion property, we prove that the finite type condition implies the weak
separation condition. By assuming the weak separation condition, we prove that the Hausdorff and box dimensions of the attractor
are equal and, if the dimension of the attractor is α, then its α-dimensional Hausdorff measure is positive and finite. We
obtain a necessary and sufficient condition for the associated self-conformal measure μ to be singular. By using these we
give a first example of a singular invariant measure μ that is associated with a non-linear IFS with overlaps. 相似文献
6.
Synthesis, polymerisation and degradation of poly(lactide-co-propylene glycol) dimethacrylate adhesives 总被引:1,自引:0,他引:1
Sze-Man Ho 《European Polymer Journal》2006,42(8):1775-1785
Fluid ABA triblock poly(lactide-co-propylene glycol-co-lactide)s with 7, 17 or 34 propylene glycol and 2, 4, or 8 lactic acid units in each B and A block, respectively, end capped with methacrylate groups were prepared and polymerisation rates upon blue light exposure for 60, 120 or 240 s using 0.5, 1 or 2 wt.% initiators determined. The shortest monomer formulation, with 0.5 wt.% initiators, was most promising as an injectable degradable adhesive for biomedical applications, achieving 96% polymerisation by 120 s after the start of 60 s illumination, forming then a semi-rigid polymer that in water released linearly with time poly(methacrylic-co-lactic) acid degradation products. Over 14 weeks, 2 mm thick specimens largely maintained their dimensions as water sorption balanced the 19 wt.% material loss. Raising initiator concentration or monomer length reduced polymerisation rate on the lower surface of samples. Increasing the number of lactic acid units in each A block from 2 to 8 also enhanced photocrosslinked polymer water sorption and increased average total mass loss to 60 wt.% over 14 weeks but acid product release rate decreased with time. Monomers produced with longer polypropylene glycol B blocks required longer periods of light exposure for full cure and the final polymers exhibited slower non-linear hydrolytic degradation. 相似文献
7.
Sze-Man Ngai 《Proceedings of the American Mathematical Society》1997,125(10):2943-2951
We give a rigorous proof of the following heuristic result: Let be a Borel probability measure and let be the -spectrum of . If is differentiable at , then the Hausdorff dimension and the entropy dimension of equal . Our result improves significantly some recent results of a similar nature; it is also of particular interest for computing the Hausdorff and entropy dimensions of the class of self-similar measures defined by maps which do not satisfy the open set condition.
8.
We prove that the Heighway dragon is a countable union of closed geometrically similar disk-like planar sets which intersect
each other in a linear order: any two of them intersect at no more than one cut point and for any three disks there exist
at least two with an empty intersection. Consequently, the interior of the Heighway dragon is a countable union of disjoint
open disk-like planar sets. We determine all the cut points of the dragon and show that each disk-like subset between two
cut points is a graph self-similar set defined by a graph-directed iterated function system consisting of four seed sets.
Our results describe a fairly complete picture of the topological and geometric structure of the Heighway dragon. 相似文献
9.
We extend both the weak separation condition and the finite type condition to include finite iterated function systems (IFSs)
of injective C
1 conformal contractions on compact subsets of . For conformal IFSs satisfying the bounded distortion property, we prove that the finite type condition implies the weak
separation condition. By assuming the weak separation condition, we prove that the Hausdorff and box dimensions of the attractor
are equal and, if the dimension of the attractor is α, then its α-dimensional Hausdorff measure is positive and finite. We
obtain a necessary and sufficient condition for the associated self-conformal measure μ to be singular. By using these we
give a first example of a singular invariant measure μ that is associated with a non-linear IFS with overlaps.
The authors are supported in part by an HKRGC grant. 相似文献
10.