89,273 research outputs found
On the local-indicability cohen–lyndon theorem
No full textFor a group H and a subset X of H, we let HX denote the set {hxh?1 | h ? H, x ? X}, and when X is a free-generating set of H, we say that the set HX is a Whitehead subset of H. For a group F and an element r of F, we say that r is Cohen–Lyndon aspherical in F if F{r} is a Whitehead subset of the subgroup of F that is generated by F{r}. In 1963, Cohen and Lyndon (D. E. Cohen and R. C. Lyndon, Free bases for normal subgroups of free groups, Trans. Amer. Math. Soc. 108 (1963), 526–537) independently showed that in each free group each non-trivial element is Cohen–Lyndon aspherical. Their proof used the celebrated induction method devised by Magnus in 1930 to study one-relator groups. In 1987, Edjvet and Howie (M. Edjvet and J. Howie, A Cohen–Lyndon theorem for free products of locally indicable groups, J. Pure Appl. Algebra 45 (1987), 41–44) showed that if A and B are locally indicable groups, then each cyclically reduced element of A*B that does not lie in A ? B is Cohen–Lyndon aspherical in A*B. Their proof used the original Cohen–Lyndon theorem. Using Bass–Serre theory, the original Cohen–Lyndon theorem and the Edjvet–Howie theorem, one can deduce the local-indicability Cohen–Lyndon theorem: if F is a locally indicable group and T is an F-tree with trivial edge stabilisers, then each element of F that fixes no vertex of T is Cohen–Lyndon aspherical in F. Conversely, by Bass–Serre theory, the original Cohen–Lyndon theorem and the Edjvet–Howie theorem are immediate consequences of the local-indicability Cohen–Lyndon theorem. In this paper we give a detailed review of a Bass–Serre theoretical form of Howie induction and arrange the arguments of Edjvet and Howie into a Howie-inductive proof of the local-indicability Cohen–Lyndon theorem that uses neither Magnus induction nor the original Cohen–Lyndon theorem. We conclude with a review of some standard applications of Cohen–Lyndon asphericit
Music and Global Health (Theresa A. Allison, Daniel B. Reed & Judah M. Cohen, Eds.)
No full textThis is a review of the book "Music and Global Health" edited by Theresa A. Allison, Daniel B. Reed, and Judah M. Cohen.
Title: Music and Global Health | Editors: Theresa A. Allison, Daniel B. Reed, & Judah M. Cohen | Publication year: 2017 (volume 54, issue 1-2) | Publisher: Journal of Folklore Research | Pages: 159 | ISSN: 0737-703
Upper Cohen-Macaulay Dimension
No full textIn this paper, we define a homological invariant for finitely generated modules over a commutative noetherian local ring, which we call upper Cohen-Macaulay dimension. This invariant is quite similar to Cohen-Macaulay dimension that has been introduced by Gerko. Also we
define a homological invariant with respect to a local homomorphism of local rings. This invariant links upper Cohen-Macaulay dimension with Gorenstein dimension.</p
Arthur M. Cohen et Florence B. Brawer. — The American College
No full textLadret Brigitte. Arthur M. Cohen et Florence B. Brawer. — The American College. In: Revue Française d'Etudes Américaines, N°16, février 1983. Les intellectuels aux Etats-Unis. p. 163
Fibre Leather Manufacturing Corp., (Bldg.) Morris L. Cohen, Marcus L. Cohen and Leon M. Cohen d/b/a New Bedford Manufacturing Company, Ten. (1946)
No full textPlan of a Fibre Leather Manufacturing Corp., (Bldg.) Morris L. Cohen, Marcus L. Cohen and Leon M. Cohen d/b/a New Bedford Manufacturing Company, Ten. site in New Bedford, Massachusetts from June 05, 1946.https://digitalcommons.usm.maine.edu/oml-athm-collection/1185/thumbnail.jp
M. Cary. A history of the Greek world, from 323 to 146 B. C.
No full textCohen Robert. M. Cary. A history of the Greek world, from 323 to 146 B. C.. In: Revue des Études Grecques, tome 46, fascicule 217, Juillet-septembre 1933. pp. 350-351
Burgess (Stanley M.) McGee (Gary B.) Alexander (Patrick H.) eds Dictionary of Pentecostal and Charismatic Movements
No full textCohen Martine. Burgess (Stanley M.) McGee (Gary B.) Alexander (Patrick H.) eds Dictionary of Pentecostal and Charismatic Movements. In: Archives de sciences sociales des religions, n°72, 1990. p. 237
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
Get PDFThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Analysis of Air Conditioning Effectiveness vs. Outdoor Conditions: Traditional Bins or Joint Frequency Bins?
Get PDFThere are a number of methods used to
estimate the effectiveness of air conditioning
equipment in handling loads. Full hourly
computer simulations are probably the most
accurate, but lack flexibility and are more
cumbersome to use than more compact
approaches. Alternately, some form of binned
weather data has been used with load and
performance estimation carried out for each of
the bin weather conditions. The most common
binning method puts weather into bins of dry
bulb temperature with mean coincident wet bulb
temperatures.
Mean coincident humidity terms lose the
extreme humidity levels that commonly exist.
This can lead one to assume that conditions will
be held at all times, while in fact the humidity
loads will not be met and discomfort, among
other consequences, will result. Three-dimensional
plots of the joint frequency results
clearly illustrate problem areas.
A better procedure, it will be shown, is to
use a joint frequency bin data set, which puts
hours of occurrence into a matrix with dry bulb
ranges on one axis and humidity ratio ranges on
the second axis. This form of binning is easily
accomplished if a utility like BinMaker is
used to generate the binned data set
Marriage record of Cohen, M. Henry and Wolff, Julia
No full textMarriage license for M. Henry Cohen and Julia Wolff. B. Rabbi Rabhino was the officiant
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