In this paper we determine the proximity functions of the sum and the maximum of componentwise (reciprocal) quotients of positive vectors. For the sum of quotients, denoted by Q1, the proximity function is just a componentwise shrinkage function which we call q-shrinkage. This is similar to the proximity function of the l1-norm which is given by componentwise soft shrinkage. For the maximum of ...

December 13-15, 2007: Firenze, Italy, ed. by C. Manfredi, ISBN 978 88-8453-673-3 (print) ISBN 978-88-8453-674-7 (online) © Firenze university press, 2007. Abstract: The approximate entropy of vowel phonation spectra has been used to reveal two normal voicing groups in healthy males. An analysis of the corresponding open and closed quotients for the groups shows the first with balanced quotients...

Participants (230) from Germany and 20 laboratories in 11 European countries took part in a newly designed cerebrospinal fluid (CSF) survey distributed by INSTAND. Conventional proficiency testing for albumin, IgG, IgA, and IgM in CSF and serum, for total protein in CSF, and for oligoclonal IgG in CSF and serum was combined with evaluation and interpretation of CSF/serum quotients in quotient d...

In this paper we propose a method for blind signal decomposition that does not require the independence or stationarity of the sources. We define suitable quotients of linear combinations of the images of the mixtures in a given frame and we show experimentally that such quotients can be used to recursively extract three sources from only two measurements. A general strategy to extract more tha...

The purpose of the present paper is to explain the fake projective plane constructed by J. H. Keum from the point of view of arithmetic ball quotients. Beside the ball quotient associated with the fake projective plane, we also analize two further naturally related ball quotients whose minimal desingularizations lead to two elliptic surfaces, one already considered by J. H. Keum as well as the ...

We develop algorithms to turn quotients of rings of rings of integers into effective Euclidean rings by giving polynomial algorithms for all fundamental ring operations. In addition, we study normal forms for modules over such rings and their behavior under certain quotients. We illustrate the power of our ideas in a new modular normal form algorithm for modules over rings of integers, vastly o...

We define a nontrivial homomorphism from the Hecke algebra of type B onto a reduced algebra of the Hecke algebra of type A at roots of unity. We use this homomorphism to describe semisimple quotients of the Hecke algebra of type B at roots of unity. Using these quotients we determine subfactors obtained from the inclusion of Hecke algebra of type A into Hecke algebras of type B. We also study i...

We construct and study two series of curves whose Jacobians admit complex multiplication. The curves arise as quotients of Galois coverings of the projective line with Galois group metacyclic groups Gq,3 of order 3q with q ≡ 1 mod 3 an odd prime, and Gm of order 2 . The complex multiplications arise as quotients of double coset algebras of the Galois groups of these coverings. We work out the C...

We construct a birational equivalence between certain quotients of s-tuples of equidimensional linear subspaces of Cn and some quotients of products of square matrices modulo diagonal conjugations. In particular, we prove the rationality of the quotient space of s-tuples of linear 2-planes in Cn modulo the diagonal GLn(C)-action . Furthermore, we compute generators of the field of the rational ...

We show that the only shrinking gradient solitons with vanishing Weyl tensor are quotients of the standard ones Sn, S × R, and Rn. This gives a new proof of the Hamilton-Ivey-Perel’man classification of 3dimensional shrinking gradient solitons. We also show that gradient solitons with constant scalar curvature and suitably decaying Weyl tensor when noncompact are quotients of Hn, H × R, Rn, S ×...