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Felix Klein 《Mathematische Annalen》1870,2(2):198-226
Ohne Zusammenfassung 相似文献
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F. Klein 《Mathematische Annalen》1883,22(2):246-248
Ohne ZusammenfassungAus den Sitzungsberichten der physikalisch-medicinischen Societät zu Erlangen vom 10. November 1873Es ist dies diejenige Arbeit, auf welche Hr. Wedekind bei seiner Definition des complexen Doppelverhältnisses von vier Punkten der Kugel Bezug nimmt, Bd. 9 dieser Annalen, pag. 209 ff. [Febr. 1883]. 相似文献
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F. Klein 《Fresenius' Journal of Analytical Chemistry》1885,24(1):379-388
Ohne ZusammenfassungNieder-Ingelheim, 3. Mai 1885. 相似文献
7.
A time discrete scheme is used to approximate the solution toa phase field system of PenroseFife type with a non-conservedorder parameter. An a posteriori error estimate is presentedthat allows the estimation of the difference between continuousand semidiscrete solutions by quantities that can be calculatedfrom the approximation and given data. 相似文献
8.
Andrea Mühlbauer Stephan Seip Alexander Nowak VanSung Tran 《Helvetica chimica acta》2003,86(6):2065-2072
Chemical investigation of the roots of the Vietnamese plant Tacca paxiana resulted in the isolation of five new steroidal compounds, taccalonolide R ( 6 ), S ( 7 ), T ( 8 ), U ( 9 ), and V ( 10 ). Their structures were established on the basis of NMR and mass‐spectral data. In addition, the five known taccalonolides A ( 1 ), B ( 2 ), E ( 3 ), K ( 4 ), and N ( 5 ) were also isolated and identified. 相似文献
9.
Stephan Kreutzer 《Annals of Pure and Applied Logic》2004,130(1-3):61-78
We study the relationship between least and inflationary fixed-point logic. In 1986, Gurevich and Shelah proved that in the restriction to finite structures, the two logics have the same expressive power. On infinite structures however, the question whether there is a formula in IFP not equivalent to any LFP-formula was left open.
In this paper, we answer the question negatively, i.e. we show that the two logics are equally expressive on arbitrary structures. We give a syntactic translation of IFP-formulae to LFP-formulae such that the two formulae are equivalent on all structures.
As a consequence of the proof we establish a close correspondence between the LFP-alternation hierarchy and the IFP-nesting depth hierarchy. We also show that the alternation hierarchy for IFP collapses to the first level, i.e. the complement of any inflationary fixed point is itself an inflationary fixed point. 相似文献
10.
Many biological and medical studies have as a response of interest the time to occurrence of some event, such as the occurrence of a particular symptom or disease, remission, relapse, death due to some specific disease, or simply death. In this paper we study the problem of assessing the effect of potential risk factors on the outcome event of interest through a parametric or semi-parametric frailty model where the lifetimes have a reason to be considered dependent. This dependence may arise because of multiple endpoints within the same individual or because, when studying a single endpoint, there are natural groupings between study subjects. The objective of this paper is to extend both parametric and semi-parametric approaches to regression analysis in which the lifetimes of individuals in a group are effected by the same random frailty which follows a positive stable distribution. Some comparisons of the properties of this frailty distribution with other frailty distributions are made and an example which assesses the effect of a treatment in a litter-matched tumorigenesis study is presented. 相似文献