La motivación estructural de la palatalización

This paper is about the structural motivation of the palatalization of coronal stops in Brazilian Portuguese (BP) and cross-linguistically. It aims to explain why (a) coronal stop consonants are the typical targets of the process, (b) coronal stops are the only targets of the process in BP, (c) the typical trigger of palatalization crosslinguistically is the coronal high vowel, (d) the only trigger of the process in BP is the coronal high vowel. We propose an internal structure of segments with abstract elements C and V (VAN DER HULST, 2005, 2011) and show that the consonantality of high front vocoids is the motivation of palatalization. The process tends to affect consonants which are similar to the trigger in structural terms. The proposal allows us to distinguish secondary and full palatalization (BATEMAN, 2007) structurally. It also explainsthe selection of trigger and targets of palatalization in BP, which results of full palatalization, a kind of palatalization which demands maximally identical trigger and targets.Este artigo trata da motivação estrutural da palatalização de consoantes plosivas coronais em português brasileiro (PB) e nas línguas do mundo. O objetivo é explicar por que (a) as plosivas coronais são o alvo típico do processo, (b) as plosivas coronais são o único alvo do processo em PB, (c) o gatilho típico da palatalização nas línguas do mundo é a vogal alta coronal , (d) o único gatilho do processo em PB é a vogal alta coronal. Propomos uma estrutura interna dos segmentos com os elementos abstratos C e V (VAN DER HULST, 2005, 2011) e mostramos que a consonantalidade dos vocoides anteriores altos é a motivação estrutural da palatalização. O processo tende a afetar consoantes semelhantes ao gatilho em termos estruturais. A proposta permite distinguir estruturalmente a palatalização secundária e a palatalização plena (BATEMAN, 2007). Também explica a seleção de gatilhos e alvos de palatalização em PB, que resultam de palatalização plena, um tipo de palatalização que exige gatilhos e alvos maximamente idênticos.Este artículo aborda la motivación estructural de la palatalización de las consonantes oclusivas coronales en portugués brasileño (PB) y en las lenguas del mundo. El objetivo es explicar por qué (a) las oclusivas coronales son el objetivo típico del proceso, (b) las oclusivas coronales son el único objetivo del proceso en PB, (c) el desencadenante típico de la palatalización es la vocal coronal alta /i/, (d) el único desencadenante del proceso em PB es la vocal coronal alta. Proponemos una estructura interna de los segmentos con los elementos abstractos C y V (VAN DER HULST, 2005, 2011) y mostramos que la consonantalidad de los vocoides anteriores altos es la motivación estructural de la palatalización. El proceso tiende a afectar consonantes similares al desencadenante en términos estructurales. La propuesta permite distinguir estructuralmente la palatalización secundaria y la palatalización completa (BATEMAN,2007). También explica la selección de desencadenantes y objetivos de palatalización en PB, que resultan de la palatalización completa, un tipo de palatalización que requiere desencadenantes y objetivos máximamente idénticos

A new envelope function for nonsmooth DC optimization

Difference-of-convex (DC) optimization problems are shown to be equivalent to the minimization of a Lipschitz-differentiable "envelope". A gradient method on this surrogate function yields a novel (sub)gradient-free proximal algorithm which is inherently parallelizable and can handle fully nonsmooth formulations. Newton-type methods such as L-BFGS are directly applicable with a classical linesearch. Our analysis reveals a deep kinship between the novel DC envelope and the forward-backward envelope, the former being a smooth and convexity-preserving nonlinear reparametrization of the latter

QPALM: A Newton-type Proximal Augmented Lagrangian Method for Quadratic Programs

We present a proximal augmented Lagrangian based solver for general convex quadratic programs (QPs), relying on semismooth Newton iterations with exact line search to solve the inner subproblems. The exact line search reduces in this case to finding the zero of a one-dimensional monotone, piecewise affine function and can be carried out very efficiently. Our algorithm requires the solution of a linear system at every iteration, but as the matrix to be factorized depends on the active constraints, efficient sparse factorization updates can be employed like in active-set methods. Both primal and dual residuals can be enforced down to strict tolerances and otherwise infeasibility can be detected from intermediate iterates. A C implementation of the proposed algorithm is tested and benchmarked against other state-of-the-art QP solvers for a large variety of problem data and shown to compare favorably against these solvers