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101.
We develop a new joint cure rate model for longitudinal and survival data. The model allows for multiple longitudinal markers as well as a cure structure for the survival component based on the promotion time cure rate model, as described in Ibrahim et al. (Bayesian Survival Analysis, Springer, New York, 2001). Several characteristics and properties of the new model are discussed and examined. A real dataset from a melanoma clinical trial is given to demonstrate the methodology. 相似文献
102.
Vieri Benci 《Advances in Mathematics》2003,173(1):50-67
The notions of “labelled set” and “numerosity” are introduced to generalize the counting process of finite sets. The resulting numbers, called numerosities, are then used to develop nonstandard analysis. The existence of a numerosity function is equivalent to the existence of a selective ultrafilter, hence it is independent of the axioms of ZFC. 相似文献
103.
Antal Járai 《Aequationes Mathematicae》2003,65(3):236-266
Summary. We prove that - under certain conditions - measurable solutions $f$ of the functional equation $f(x)=h(x,y,f(g_{1}(x,y)),\ldots,f(g_{n}(x,y))),\quad(x,y)\in D \subset \mathbb{R}^{s} \times \mathbb{R}^{l}$ are continuous, even if $1\le l\le s$. As a tool we introduce new classes of functions which - roughly speaking - interpolate between continuous and Lebesgue measurable functions. Connection between these classes are also investigated. 相似文献
104.
Dimitri Leemans 《Journal of Geometry》2004,79(1-2):146-155
We construct nine rank five incidence geometries that are firm and residually connected
and on which the Mathieu group M22 acts flag-transitively. The constructions use
mainly objects arising from the Steiner systemS(3, 6, 22).
One of these geometries was constructed by Meixner and Pasini in [10]. Three of them
are obtained from the geometry of Meixner and Pasini using doubling (see [8] or [12]) or similar
constructions. The remaining five are new and four of them have a star diagram. These
latter four geometries are constructed using special partitions of the 22 points of
the Steiner system S(3, 6, 22). 相似文献
105.
Summary The detachment of a rubber matrix from a rigid inclusion under monotonic loading and at subsequent relaxation is investigated within two dimensional analysis. Examined are stress–strain experimental data acquired with the help of a test bed equipped with a digital image-acquisition device. The influence of the interfacial bonding strength and the particle size on the detachment process is analyzed. The influence of the interfacial bonding strength is visible in the stress–strain diagram of loading and in the recorded images. The relaxation test reveals no influence of the bonding strength on the stress-relaxation. However, the image analysis indicates a secondary transient creep of the contour of detachment, which depends on the interfacial bonding. 相似文献
106.
The aim of this note is to generalize and apply results on matrix continued fractions representing the solution of discrete matrix Riccati equations. Assuming uniform bounds for the norm of the matrix coefficients of the continued fraction, the minimal and maximal solutions of the corresponding algebraic Riccati equation can be accurately enclosed. 相似文献
107.
研究了钍与5-(对羧基苯偶氮)-8-羟基喹啉(5-CPAHQ)的显色反应条件:在阳离子表面活性剂十六烷基三甲基溴化铵(CTMAB)存在下,pH4.4-5.4缓冲介质中,形成稳定的橙红色络合物,最大吸收波长为490nm,ε=1.10×105L·mol-1·cm-1,钍在0-9μg/25mL范围内符合比尔定律。用TBP萃淋树脂分离,该方法可用于测定矿石中的微量钍。 相似文献
108.
Ignasi Mundet i Riera 《Topology》2003,42(3):525-553
In this paper we introduce invariants of semi-free Hamiltonian actions of S1 on compact symplectic manifolds using the space of solutions to certain gauge theoretical equations. These equations generalise both the vortex equations and the holomorphicity equation used in Gromov-Witten theory. In the definition of the invariants we combine ideas coming from gauge theory and the ideas underlying the construction of Gromov-Witten invariants. 相似文献
109.
Let p a prime, X = SL2(pa) and K = GF(pa). For S a Sylow p-subgroup of X, we explicitly describe the structure of the commutator series of S on each of the irreducible KX-modules.Received: 28 April 2004 相似文献
110.
The surface body is a generalization of the floating body. Its relation to p-affine surface area is studied. 相似文献