A proposal of PSO particles' initialization, for costly unconstrained optimization problems: ORTHOinit

Abstract. A proposal for particles’ initialization in PSO is presented and discussed, with focus on costly global unconstrained optimization problems. The standard PSO iteration is reformulated such that the trajectories of the particles are studied in an extended space, combining particles’ position and speed. To the aim of exploring effectively and efficiently the optimization search space since the early iterations, the particles are initialized using sets of orthogonal vectors in the extended space (orthogonal initialization, ORTHOinit). Theoretical derivation and application to a simulation-based optimization problem in ship design are presented, showing the potential benefits of the current approach

An Estimation of Distribution Particle Swarm Optimization Algorithm

In this paper we present an estimation of distribution par-ticle swarm optimization algorithm that borrows ideas from recent de-velopments in ant colony optimization. In the classical particle swarm optimization algorithm, particles exploit their individual memory to ex-plore the search space. However, the swarm as a whole has no means to exploit its collective memory (represented by the array of pbests) to guide its search. This causes a re-exploration of already known bad regions of the search space, wasting costly function evaluations. In our approach, we use the swarms collective memory to estimate the distribu-tion of promising regions in the search space and probabilistically guide the particles movement towards them. Our experiments show that this approach is able to find similar or better solutions than the standard particle swarm optimizer with fewer function evaluations

AnÃlise sociofuncionalista da variaÃÃo de concordÃncia verbal em construÃÃes de voz passiva sintÃtica em textos jornalÃsticos cearenses

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgicoNosso trabalho investiga como a realizaÃÃo variÃvel de concordÃncia verbal em construÃÃes de voz passiva sintÃtica, com a alternÃncia entre a presenÃa e a ausÃncia de marca explÃcita de plural no verbo de 3 pessoa, apresenta-se no atual contexto linguÃstico cearense, especificamente em dois jornais locais: O Povo e DiÃrio do Nordeste. Para isso, selecionamos 240 ediÃÃes, durante o perÃodo de janeiro a dezembro de 2016, levando-se em consideraÃÃo trÃs gÃneros textuais: editoriais, artigos de opiniÃo e notÃcias. No total, coletamos 121 dados referentes à variaÃÃo de concordÃncia verbal com a construÃÃo de voz passiva sintÃtica, os quais foram submetidos ao programa computacional estatÃstico Goldvarb X, que gerou frequÃncias e pesos relativos que serviram de base para a descriÃÃo e anÃlise dos dados. O programa apontou que a ausÃncia de marca explÃcita de plural no verbo com a voz passiva sintÃtica à condicionada essencialmente por dois grupos de fatores: um linguÃstico, forma verbal, e outro extralinguÃstico, gÃnero textual. Contudo, o nÃmero de dados em que o verbo apresenta marca explÃcita de plural (59,5%) mostrou-se mais representativo do que o somatÃrio dos dados em que o verbo nÃo consta da marca explÃcita de plural (40,5%). Para o desenvolvimento deste trabalho, utilizamo-nos dos pressupostos teÃrico-metodolÃgicos da SociolinguÃstica Variacionista (LABOV, 2008), conjugados a princÃpios funcionalistas, em especial, o PrincÃpio da MarcaÃÃo (GIVÃN, 1995) e o PrincÃpio da Expressividade (DU BOIS & VOTRE, 2012). AlÃm da possÃvel mudanÃa em direÃÃo à indeterminaÃÃo com a construÃÃo de voz passiva sintÃtica, concluÃmos que, no grupo de fatores linguÃsticos forma verbal, as formas perifrÃsticas e infinitivas, especialmente com esse tipo de construÃÃo, tendem a ser realizadas sem a presenÃa do morfema de plural, como uma manobra para reduzir ou anular o esforÃo de codificaÃÃo, motivada em termos de expressividade e de eficÃcia comunicativa. Jà em relaÃÃo ao grupo extralinguÃstico gÃnero textual, hà tendÃncia de que formas mais marcadas ocorram em contextos mais marcados e as menos marcadas em contextos menos marcados, ou seja, formas verbais mais marcadas em construÃÃes de voz passiva sintÃtica â com a presenÃa de morfema de plural â tendem a ocorrer em contextos mais marcados, como no gÃnero textual editorial, ao passo que formas verbais menos marcadas â com a ausÃncia de morfema de plural â tendem a ocorrer em contextos menos marcados, como no gÃnero textual notÃcia.Our work investigate how the variable fulfillment of verbal concord in synthetic passive voice constructions, alternating between the presence and absence of explicit mark of plural in the third person of verb forms, is presented in the current linguistic context of CearÃ, specifically in two local newspapers: O Povo and DiÃrio do Nordeste. In order to reach this goal, we selected 240 editions focusing on three textual genres: editorial, opinion article, and news from January to December, 2016. A number of 121 data concerning the variation of verbal concord with the synthetic passive voice construction was selected and submitted to the statistical computer program Goldvarb X which generated frequencies and relative weight that served as basis to the description and data analysis. The program pointed out that the absence of the explicit mark of the plural in the verb with the synthetic passive voice is subject to two groups of factors: one linguistic, verbal form; and the other extralinguistic, textual genre. However, the number of data in which the verb presents explicit mark of plural (59.5%) claimed to be more representative than the amount of data in which the verb is not present in the explicit mark of plural (40.5%). In order to develop this research, we used as theoretical-methodological basis the Sociolinguistic Variation (LABOV, 2008), attached to the functionalist principles, notably to the Markedness Principle (GIVÃN, 1995) and the Principle of Expressiveness (DU BOIS & VOTRE, 2012). Besides the possible change towards the indetermination due to the use of the synthetic passive voice, we conclude that as for the group verbal form the periphrastic and infinitive forms, especially with this type of construction. The aforementioned forms tend to be fulfilled without the presence of the plural morpheme as a device to reduce or set aside the codification effort and motivated in terms of expressiveness and communicative accuracy. As far as the extralinguistic group textual genre is concerned, there is a tendency that more marked forms occur in contexts that are more marked and less marked forms occur in contexts that are less marked as well. In summary, more marked verbal forms in synthetic passive voice â with the presence of a plural morpheme - tend to appear in contexts that are more marked such as in textual genre editorial whereas less marked verbal forms â absence of plural morpheme â tend to occur in contexts that are less marked such as in the news textual genr