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81.
Olaf Kster Bernd Marx Peter Gemmar Markus M. Hess Hermann Josef Künzel 《Journal of voice》1999,13(3):355-374
High-speed filming is one of the most informative methods for assessing voice physiology data. Tracing high-speed images of the glottis provides quantitative parameters such as the glottal area and the glottal width function. By way of example, a number of studies are discussed which extract quantitative data from high-speed images showing voice onsets. Furthermore, a new computer system (MVAS; multi-dimensional voice analysis system) is presented that synchronously displays a laryngoscopic high-speed film, the electroglottographical signal, and several acoustic analyses of the recorded voice sample. The automatic measurement of glottal width and glottal area from the laryngoscopic images is also provided. Looking at former studies and our analyses of voice onsets reveals a tremendous intersubject and even intrasubject variability (different prephonatory closure, different time span until full amplitude is reached, different open quotient). 相似文献
82.
83.
Arie Hordijk Olaf Passchier Floske Spieksma 《Mathematical Methods of Operations Research》1997,45(2):281-301
In this paper we will consider two-person zero-sum games and derive a general approach for solving them. We apply this approach to a queueing problem. In section 1 we will introduce the model and formulate the Key-theorem. In section 2 we develop the theory that we will use in section 3 to prove the Key-theorem. This includes a general and useful result in Lemma 2.1 on the sufficiency of stationary policies. 相似文献
84.
The co-degrees of irreducible characters 总被引:1,自引:0,他引:1
LetG be a finite group. The co-degree of an irreducible character χ ofG is defined to be the number |G|/χ(1). The set of all prime divisors of all the co-degrees of the nonlinear irreducible characters ofG is denoted by Σ(G). First we show that Σ(G)=π(G) (the set of all prime divisors of |G|) unlessG is nilpotent-by-abelian. Then we make Σ(G) a graph by adjoining two elements of Σ(G) if and only if their product divides a co-degree of some nonlinear character ofG. We show that the graph Σ(G) is connected and has diameter at most 2. Additional information on the graph is given. These results are analogs to theorems
obtained for the graph corresponding to the character degrees (by Manz, Staszewski, Willems and Wolf) and for the graph corresponding
to the class sizes (by Bertram, Herzog and Mann). Finally, we investigate groups with some restriction on the co-degrees.
Among other results we show that ifG has a co-degree which is ap-power for some primep, then the corresponding character is monomial andO
p
(G)≠1. Also we describe groups in which each co-degree of a nonlinear character is divisible by at most two primes. These results
generalize results of Chillag and Herzog. Other results are proved as well.
The paper was written during this author’s visit at the Technion and the University of Tel Aviv. He would like to thank the
departments of mathematics at the Technion and the University of Tel Aviv for their hospitality and support. 相似文献
85.
86.
87.
Mihaela Carmen Balaban Cyril Chappaz-Gillot Olaf Fuhr Christian Roussel 《Tetrahedron》2009,65(18):3733-193
meso-Bromoporphyrins can be conveniently substituted by primary and secondary amines in a metal catalyst-free reaction which gives access to a large variety of meso-N-substituted derivatives. In some cases, considerable acceleration of this amination can be effected under microwave irradiation. The amino anchor on the porphyrin skeleton is useful for constructing novel self-assembling porphyrinoids as demonstrated by a single crystal X-ray analysis as well as stationary absorption and fluorescence spectroscopies. 相似文献
88.
Let be a one-parameter family of positive integral operators on a locally compact space . For a possibly non-uniform partition of define a finite measure on the path space by using a) for the transition between any two consecutive partition times of distance and b) a suitable continuous interpolation scheme (e.g. Brownian bridges or geodesics). If necessary normalize the result
to get a probability measure. We prove a version of Chernoff's theorem of semigroup theory and tightness results which yield
convergence in law of such measures as the partition gets finer. In particular let be a closed smooth submanifold of a manifold . We prove convergence of Brownian motion on , conditioned to visit at all partition times, to a process on whose law has a density with respect to Brownian motion on which contains scalar, mean and sectional curvatures terms. Various approximation schemes for Brownian motion on are also given.
相似文献
89.
The effect of long-range forces on the dynamics of a bar 总被引:2,自引:0,他引:2
Olaf Weckner 《Journal of the mechanics and physics of solids》2005,53(3):705-728
The one-dimensional dynamic response of an infinite bar composed of a linear “microelastic material” is examined. The principal physical characteristic of this constitutive model is that it accounts for the effects of long-range forces. The general theory that describes our setting, including the accompanying equation of motion, was developed independently by Kunin (Elastic Media with Microstructure I, 1982), Rogula (Nonlocal Theory of Material Media, 1982) and Silling (J. Mech. Phys. Solids 48 (2000) 175), and is called the peridynamic theory. The general initial-value problem is solved and the motion is found to be dispersive as a consequence of the long-range forces. The result converges, in the limit of short-range forces, to the classical result for a linearly elastic medium. Explicit solutions in elementary form are given in a broad class of special cases. The most striking observations arise in the Riemann-like problem corresponding to a constant initial displacement field and a piecewise constant initial velocity field. Even though, initially, the displacement field is continuous, it involves a jump discontinuity for all later times, the Lagrangian location of which remains stationary. For some materials the magnitude of the discontinuity-jump oscillates about an average value, while for others it grows monotonically, presumably fracturing the material when it exceeds some critical level. 相似文献
90.
A method of combining moiré interferometry and the finite-element method to effect localized stress analysis is presented.
The displacement data from local regions of interest in the optical experiment are used as boundary conditions for the finite-element
stress analysis.
The stability of the method is examined with data from simple numerical models one of which corresponded to the stress analysis
of a pin-loaded plate with friction. These studies show that the method requires the sensivity of moiré interferometry for
successful implementation, i.e., displacement data accuracy within 0.1 μm or 4 μin.
This localized hybrid method of stress analysis provides a powerful and efficient method for the reduction of experimental
data. 相似文献