Search results for "Descent"
showing 10 items of 99 documents
An optimality test for semi-infinite linear programming
1992
In this paper we present a test to characterize the optimal solutions for the continuous semi-infinite linear programming problem. This optimality characterization is a condition of Kuhn–Tucker type. The resolution of a linear program permits to check the optimality of a feasible point,to detect the unboundedness of the problem and to find descent directions. We give some illustrative examples. We show that the local Mangasarian–Fromovitz constraint qualification is almost equivalent to Slater qualification for this problem. Furthermore, it follows from our study that this optimality condition is always necessary for a wide class of semi-infinite linear programming problems
Cambio estructural en economías en transición : el impacto de la privatización sobre la restricción presupuestaria de las empresas rusas
1999
La transición desde una economía de planificación central hacia una economía de mercado exigía el establecimiento de las condiciones necesarias para que se produjese una transformación de la gestión empresarial, de las cuales la privatización de las empresas estatales constituía un elemento vital. No obstante, resultaba obvio que sin algunos cambios en el ámbito microeconómico las esperanzas para una transformación del sistema económico, tras más de seis décadas de economía planificada, no podrían verse cumplidas. Un cambio exógeno en la estructura de propiedad estrictamente en términos legales -esto es, de una regla formal- sin que los gestores de las empresas asimilen el cambio, transform…
Integration of gradient based and response surface methods to develop a cascade optimisation strategy for Y-shaped tube hydroforming process design
2010
International audience; In the last years a strong research effort was produced in order to develop and design new forming technologies able to overcome the typical drawbacks of traditional forming operations. Among such new technologies, hydroforming proved to be one of the most promising. The design of tube hydroforming operations is mainly aimed to prevent bursting or buckling occurrence and such issues can be pursued only if a proper control of both material feeding history and internal pressure path during the process is performed.In this paper, a proper optimisation strategy was developed on Y-shaped tube hydroforming process which is characterized by a quite complex process mechanics…
Online shortest paths with confidence intervals for routing in a time varying random network
2018
International audience; The increase in the world's population and rising standards of living is leading to an ever-increasing number of vehicles on the roads, and with it ever-increasing difficulties in traffic management. This traffic management in transport networks can be clearly optimized by using information and communication technologies referred as Intelligent Transport Systems (ITS). This management problem is usually reformulated as finding the shortest path in a time varying random graph. In this article, an online shortest path computation using stochastic gradient descent is proposed. This routing algorithm for ITS traffic management is based on the online Frank-Wolfe approach.…
Time scales of adaptive behavior and motor learning in the presence of stochastic perturbations.
2009
In this paper, the major assumptions of influential approaches to the structure of variability in practice conditions are discussed from the perspective of a generalized evolving attractor landscape model of motor learning. The efficacy of the practice condition effects is considered in relation to the theoretical influence of stochastic perturbations in models of gradient descent learning of multiple dimension landscapes. A model for motor learning is presented combining simulated annealing and stochastic resonance phenomena against the background of different time scales for adaptation and learning processes. The practical consequences of the model's assumptions for the structure of pract…
New descent rules for solving the linear semi-infinite programming problem
1994
The algorithm described in this paper approaches the optimal solution of a continuous semi-infinite linear programming problem through a sequence of basic feasible solutions. The descent rules that we present for the improvement step are quite different when one deals with non-degenerate or degenerate extreme points. For the non-degenerate case we use a simplex-type approach, and for the other case a search direction scheme is applied. Some numerical examples illustrating the method are given.
The afterworld space in the "Poem strip" (1969) by Dino Buzzati
2018
L’obiettivo del contributo è l’analisi dello spazio oltremondano in Poema a fumetti(1969) di Dino Buzzati, graphic novelante-litteram. Buzzati riscrive, in chiave ultramoderna e laica, sia il mito di Orfeo ed Euridice, restituendo la centralità alla potenza della musica, sia il mito della discesa agli inferi, toposassoluto della letteratura italiana a partire da Dante e rappresentazione allegorica dell’oltretomba cristiano. In particolare Buzzati inventa una rappresentazione visiva dello spazio dell’aldilà dove sono essenziali due elementi: la continuità/discontinuità dei due mondi, nominalmente diversi, e le cornici che permettono il passaggio da un mondo all’altro. Il motivo ricorrente di…
Cyclic coordinate for penalized Gaussian graphical models with symmetry restriction
2014
In this paper we propose two efficient cyclic coordinate algorithms to estimate structured concentration matrix in penalized Gaussian graphical models. Symmetry restrictions on the concentration matrix are particularly useful to reduce the number of parameters to be estimated and to create specific structured graphs. The penalized Gaussian graphical models are suitable for high-dimensional data.
Catalan words avoiding pairs of length three patterns
2021
Catalan words are particular growth-restricted words counted by the eponymous integer sequence. In this article we consider Catalan words avoiding a pair of patterns of length 3, pursuing the recent initiating work of the first and last authors and of S. Kirgizov where (among other things) the enumeration of Catalan words avoiding a patterns of length 3 is completed. More precisely, we explore systematically the structural properties of the sets of words under consideration and give enumerating results by means of recursive decomposition, constructive bijections or bivariate generating functions with respect to the length and descent number. Some of the obtained enumerating sequences are kn…
La descentralización tributaria en la Segunda República - Cataluña
1977
Investigación del desarrollo del Título IV- de la hacienda del estatuto de Nuria hasta su aprobación del 15 de septiembre de 1932. Estudio de la implantación de los traspasos de servicios su valoración y la correspondiente descentralización tributaria aprobado el Estatuto de Cataluña hasta el 18 de julio de 1936 a través de la Comisión Mixta Comisión Revisora Nueva Comisión Mixta y reanudación de la 1a Comisión Mixta demostrando la incidencia de los efectos políticos que acontecen en España sobre dichas comisiones y los efectos políticos que se producen como consecuencia de la actuación de dichas comisiones mixtas. Se aportan documentos inéditos obtenidos en archivos oficiales que iluminan …