927 resultados para Lopes, Manuel,1907-2005


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CiaoPP is the abstract interpretation-based preprocessor of the Ciao multi-paradigm (Constraint) Logic Programming system. It uses modular, incremental abstract interpretation as a fundamental tool to obtain information about programs. In CiaoPP, the semantic approximations thus produced have been applied to perform high- and low-level optimizations during program compilation, including transformations such as múltiple abstract specialization, parallelization, partial evaluation, resource usage control, and program verification. More recently, novel and promising applications of such semantic approximations are being applied in the more general context of program development such as program verification. In this work, we describe our extensión of the system to incorpórate Abstraction-Carrying Code (ACC), a novel approach to mobile code safety. ACC follows the standard strategy of associating safety certificates to programs, originally proposed in Proof Carrying- Code. A distinguishing feature of ACC is that we use an abstraction (or abstract model) of the program computed by standard static analyzers as a certifícate. The validity of the abstraction on the consumer side is checked in a single-pass by a very efficient and specialized abstractinterpreter. We have implemented and benchmarked ACC within CiaoPP. The experimental results show that the checking phase is indeed faster than the proof generation phase, and that the sizes of certificates are reasonable. Moreover, the preprocessor is based on compile-time (and run-time) tools for the certification of CLP programs with resource consumption assurances.

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We study the problem of efñcient, scalable set-sharing analysis of logic programs. We use the idea of representing sharing information as a pair of abstract substitutions, one of which is a worst-case sharing representation called a clique set, which was previously proposed for the case of inferring pair-sharing. We use the clique-set representation for (1) inferring actual set-sharing information, and (2) analysis within a topdown framework. In particular, we define the abstract functions required by standard top-down analyses, both for sharing alone and also for the case of including freeness in addition to sharing. Our experimental evaluation supports the conclusión that, for inferring set-sharing, as it was the case for inferring pair-sharing, precisión losses are limited, while useful efñciency gains are obtained. At the limit, the clique-set representation allowed analyzing some programs that exceeded memory capacity using classical sharing representations.

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Certain aspects of functional programming provide syntactic convenience, such as having a designated implicit output argument, which allows function cali nesting and sometimes results in more compact code. Functional programming also sometimes allows a more direct encoding of lazy evaluation, with its ability to deal with infinite data structures. We present a syntactic functional extensión of Prolog covering function application, predefined evaluable functors, functional definitions, quoting, and lazy evaluation. The extensión is also composable with higher-order features. We also highlight the Ciao features which help implementation and present some data on the overhead of using lazy evaluation with respect to eager evaluation.

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The relationship between abstract interpretation and partial deduction has received considerable attention and (partial) integrations have been proposed starting from both the partial deduction and abstract interpretation perspectives. In this work we present what we argüe is the first fully described generic algorithm for efñcient and precise integration of abstract interpretation and partial deduction. Taking as starting point state-of-the-art algorithms for context-sensitive, polyvariant abstract interpretation and (abstract) partial deduction, we present an algorithm which combines the best of both worlds. Key ingredients include the accurate success propagation inherent to abstract interpretation and the powerful program transformations achievable by partial deduction. In our algorithm, the calis which appear in the analysis graph are not analyzed w.r.t. the original definition of the procedure but w.r.t. specialized definitions of these procedures. Such specialized definitions are obtained by applying both unfolding and abstract executability. Our framework is parametric w.r.t. different control strategies and abstract domains. Different combinations of such parameters correspond to existing algorithms for program analysis and specialization. Simultaneously, our approach opens the door to the efñcient computation of strictly more precise results than those achievable by each of the individual techniques. The algorithm is now one of the key components of the CiaoPP analysis and specialization system.

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Recent approaches to mobile code safety, like proof- arrying code, involve associating safety information to programs. The code supplier provides a program and also includes with it a certifícate (or proof) whose validity entails compliance with a predefined safety policy. The intended benefit is that the program consumer can locally validate the certifícate w.r.t. the "untrusted" program by means of a certifícate checker—a process which should be much simpler, eflicient, and automatic than generating the original proof. We herein introduce a novel approach to mobile code safety which follows a similar scheme, but which is based throughout on the use of abstract interpretation techniques. In our framework the safety policy is specified by using an expressive assertion language defined over abstract domains. We identify a particular slice of the abstract interpretation-based static analysis results which is especially useful as a certifícate. We propose an algorithm for checking the validity of the certifícate on the consumer side which is itself in fact a very simplified and eflicient specialized abstract-interpreter. Our ideas are illustrated through an example implemented in the CiaoPP system. Though further experimentation is still required, we believe the proposed approach is of interest for bringing the automation and expressiveness which is inherent in the abstract interpretation techniques to the área of mobile code safety.

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Abstraction-Carrying Code (ACC) has recently been proposed as a framework for mobile code safety in which the code supplier provides a program together with an abstraction (or abstract model of the program) whose validity entails compliance with a predefined safety policy. The abstraction plays thus the role of safety certifícate and its generation is carried out automatically by a fixed-point analyzer. The advantage of providing a (fixed-point) abstraction to the code consumer is that its validity is checked in a single pass (i.e., one iteration) of an abstract interpretation-based checker. A main challenge to make ACC useful in practice is to reduce the size of certificates as much as possible while at the same time not increasing checking time. The intuitive idea is to only include in the certifícate information that the checker is unable to reproduce without iterating. We introduce the notion of reduced certifícate which characterizes the subset of the abstraction which a checker needs in order to validate (and re-construct) the full certifícate in a single pass. Based on this notion, we instrument a generic analysis algorithm with the necessary extensions in order to identify information which can be reconstructed by the single-pass checker. Finally, we study what the effects of reduced certificates are on the correctness and completeness of the checking process. We provide a correct checking algorithm together with sufficient conditions for ensuring its completeness. Our ideas are illustrated through a running example, implemented in the context of constraint logic programs, which shows that our approach improves state-of-the-art techniques for reducing the size of certificates.

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We discuss here different variants of the Sharing abstract domain, including the base domain that captures set-sharing, a variant to capture pairsharing, in which redundant sharing groups (w.r.t. the pair-sharing property) can be eliminated, and an alternative representation based on cliques. The original proposal for using cliques in the non-redundant version of the domain is reviewed, then extended to the base domain. Variants of all the domains including freeness alone, and freeness together with linearity are also studied.

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1. Hojas dispersas.--2. De ayer.--3. A través de un temperamento.--4. Juventud Bohemia.--5. Del fondo del alma.--6. En el proscenio y en la tribuna.

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La disputa sobre el carácter científico de la homeopatía tiene alrededor de doscientos años y, dada la magnitud de los recursos movilizados, es un tópico particularmente interesante para el análisis de su dinámica desde las ciencias sociales. En líneas generales, las controversias han puesto en cuestión dos tipos de argumentos: acerca de la eficacia de la homeopatía en términos terapéuticos (junto con las otras prácticas denominadas "terapias alternativas y/o complementarias"), y acerca del carácter "científico" de sus fundamentos, actividades y prácticas. Sin embargo, en la argumentación acerca del carácter de las terapias alternativas, ambos tópicos aparecen entremezclados, bajo el supuesto según el cual "una terapia cuyos fundamentos no pueden atribuirse al campo científico sólo podría ser eficaz como placebo (y en algunos casos, llega a ser nociva)". Numerosos tópicos de la sociología de la ciencia son aquí puestos en cuestión: el carácter objetivo de la "prueba", la "eficacia social" del conocimiento, las estrategias de legitimación "hacia adentro" y "hacia fuera" (incluidos particularmente los medios de comunicación) del campo científico, los dispositivos institucionales, entre otros. Así, desde el campo científico instituido se rechaza a la homeopatía acusándola de "no respetar los métodos de validación científicos", de "contradecir principios de la química" y de no ser "científicamente plausible". En este trabajo se analizan los principales ejes sobre los cuales se ha articulado esta controversia, tanto en la escena internacional como en la Argentina, identificando los actores que de ella han participado, discriminando, además, diferentes corrientes dentro de las "terapias alternativas o complementarias". Pretendemos identificar cuáles han sido los fundamentos de sus discursos, sobre qué supuestos se apoyan, intentando poner de manifiesto la yuxtaposición de argumentos de "cientificidad" con las luchas por el posicionamiento público y la legitimación social

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La disputa sobre el carácter científico de la homeopatía tiene alrededor de doscientos años y, dada la magnitud de los recursos movilizados, es un tópico particularmente interesante para el análisis de su dinámica desde las ciencias sociales. En líneas generales, las controversias han puesto en cuestión dos tipos de argumentos: acerca de la eficacia de la homeopatía en términos terapéuticos (junto con las otras prácticas denominadas "terapias alternativas y/o complementarias"), y acerca del carácter "científico" de sus fundamentos, actividades y prácticas. Sin embargo, en la argumentación acerca del carácter de las terapias alternativas, ambos tópicos aparecen entremezclados, bajo el supuesto según el cual "una terapia cuyos fundamentos no pueden atribuirse al campo científico sólo podría ser eficaz como placebo (y en algunos casos, llega a ser nociva)". Numerosos tópicos de la sociología de la ciencia son aquí puestos en cuestión: el carácter objetivo de la "prueba", la "eficacia social" del conocimiento, las estrategias de legitimación "hacia adentro" y "hacia fuera" (incluidos particularmente los medios de comunicación) del campo científico, los dispositivos institucionales, entre otros. Así, desde el campo científico instituido se rechaza a la homeopatía acusándola de "no respetar los métodos de validación científicos", de "contradecir principios de la química" y de no ser "científicamente plausible". En este trabajo se analizan los principales ejes sobre los cuales se ha articulado esta controversia, tanto en la escena internacional como en la Argentina, identificando los actores que de ella han participado, discriminando, además, diferentes corrientes dentro de las "terapias alternativas o complementarias". Pretendemos identificar cuáles han sido los fundamentos de sus discursos, sobre qué supuestos se apoyan, intentando poner de manifiesto la yuxtaposición de argumentos de "cientificidad" con las luchas por el posicionamiento público y la legitimación social

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La disputa sobre el carácter científico de la homeopatía tiene alrededor de doscientos años y, dada la magnitud de los recursos movilizados, es un tópico particularmente interesante para el análisis de su dinámica desde las ciencias sociales. En líneas generales, las controversias han puesto en cuestión dos tipos de argumentos: acerca de la eficacia de la homeopatía en términos terapéuticos (junto con las otras prácticas denominadas "terapias alternativas y/o complementarias"), y acerca del carácter "científico" de sus fundamentos, actividades y prácticas. Sin embargo, en la argumentación acerca del carácter de las terapias alternativas, ambos tópicos aparecen entremezclados, bajo el supuesto según el cual "una terapia cuyos fundamentos no pueden atribuirse al campo científico sólo podría ser eficaz como placebo (y en algunos casos, llega a ser nociva)". Numerosos tópicos de la sociología de la ciencia son aquí puestos en cuestión: el carácter objetivo de la "prueba", la "eficacia social" del conocimiento, las estrategias de legitimación "hacia adentro" y "hacia fuera" (incluidos particularmente los medios de comunicación) del campo científico, los dispositivos institucionales, entre otros. Así, desde el campo científico instituido se rechaza a la homeopatía acusándola de "no respetar los métodos de validación científicos", de "contradecir principios de la química" y de no ser "científicamente plausible". En este trabajo se analizan los principales ejes sobre los cuales se ha articulado esta controversia, tanto en la escena internacional como en la Argentina, identificando los actores que de ella han participado, discriminando, además, diferentes corrientes dentro de las "terapias alternativas o complementarias". Pretendemos identificar cuáles han sido los fundamentos de sus discursos, sobre qué supuestos se apoyan, intentando poner de manifiesto la yuxtaposición de argumentos de "cientificidad" con las luchas por el posicionamiento público y la legitimación social

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El presente trabajo pretende analizar cuáles eran las características climáticas que se sucedían en Madrid y su Tierra a lo largo del año, fundamentalmente entre los siglos XIV y XVI. Se intentará comprobar, dentro de las limitaciones que impone la documentación de la época, si en aquel tiempo se daba también un clima mediterráneo, o no, y si este ha variado mucho desde entonces. Igualmente se podrá comprobar algo que tal vez podría, aunque no debería, sorprendernos: el hombre medieval tenía muy claros muchos conceptos meteorológicos y climatológicos, aunque siempre aprehendidos con una finalidad práctica, para aplicarlos en su vida cotidiana tan cercana y dependiente de la naturaleza.

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The rate of consumption of alcoholic beverages has undergone changes as well as the factors that influence it. In order to understand the significance of drinking patterns, this study was conducted with a sample of young adults (N = 260) ages 20 to 30, in Lisbon. The instruments used were The Alcohol Use Disorders Identification Test and the Sense of Coherence Questionnaire. The results show that 10.8% had problems with alcohol. Those who had a lower sense of coherence, especially in the dimension of investment capacity, presented with more harmful and risky consumption patterns. We conclude that health promotion behaviors should include measures to strengthen a sense of coherence

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Trabalho apresentado no Encontro Nacional de Enfermagem: Respostas de Enfermagem para a Saúde no Fututo, 8 de abril 2015, Fundação Calouste Gulbenkian, Lisboa, Portugal

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Introdução: O pós-parto abrange o processo de transição para a parentalidade, considerado um dos principais momentos de transição ao longo da vida, responsável por mudanças a vários níveis, nomeadamente individual, conjugal, familiar e social, implicando gestão de novos sentimentos, comportamentos e preocupações com o(a) próprio(a) e com o(s), filho(s) (Kaitz, 2007; Mendes, 2009). Esta revisão integrativa da literatura foca-se nas preocupações da figura materna da díade parental no período pós-parto. Objetivos: Analisar os estudos de investigação acerca da temática das preocupações maternas no pós-parto nas sociedades contemporâneas. Metodologia: Revisão integrativa da literatura centrada na temática “preocupações maternas no pós-parto”. Utilizouse o motor de busca EBSCOhost, com acesso às bases de dados científicos: CINAHL® Complete; MEDLINE Complete; Cochrane Database of Systematic Reviews; Cochrane Methodology Register; e ainda a base de dados SCIELO ”. Obtiveramse 17 publicações científicas com a utilização do Boolean search operators “AND”, para os descritores MeSH pósparto/“ postpartum” e nascimento/“childbirth” e como tema principal “preocupações maternas”/“maternal concerns”, com disponibilidade para aceder ao texto completo, com data de publicação entre o período de Janeiro 2000 e Dezembro 2015. Resultados: Os resultados da revisão integrativa da literatura acerca da temática das preocupações maternas que pretendeu responder à questão - Quais as preocupações maternas durante o pós-parto nas sociedades contemporâneas? - agruparam-se em 5 áreas: preocupações maternas e o cuidar do recém-nascido; preocupações maternas e recuperação funcional; preocupações maternas e transição para a parentalidade; preocupações maternas e relacionamento conjugal; e preocupações maternas intergeracionais. Conclusões: Da revisão dos artigos selecionados verificou-se que as preocupações maternas refletem as necessidades das mães, no período de transição de pós-parto, assim como, as assinaladas alterações no assumir de novos papéis e da redefinição/reorganização nas responsabilidades, no seio da díade parental/família e deste modo, espelham uma área de interesse no âmbito dos cuidados à mulher/casal e família após o nascimento de um filho, de onde as intervenções de enfermagem especializada em saúde materna e obstetrícia são relevantes na avaliação da transição saudável no contexto do pós-parto, quer na vertente materna, quer na díade parental e no cuidar do recém-nascido. Palavras-chave: pós-parto; preocupações maternas; recém-nascido; nascimento Referências bibliográficas: Kaitz, M. (2007). Maternal concerns during early parenthood. Child: Care, Health and Development, 33(6), 720-727. Lugina, H., Christensson, K., Massawe, S., Nystrom, L., & Lindmark, G. (2001). Change in maternal concerns during the 6 weeks postpartum period: A study of primiparous mothers in Dar es Salaam, Tanzania. Journal of Midwifery & Women’s Health, 46(4), 248-257. doi: 10.1016/S1526-9523(01)00133-7 Lugina, H., Nyström, L., Christensson, K., & Lindmark, G. (2004). Assessing mothers’ concerns in the postpartum period: Methodological issues. Journal of Advanced Nursing, 48(3), 279-290. doi: 10.1111/j.1365-2648.2004.03197.x Mendes, I. M. (2009). Ajustamento materno e paterno: Experiências vivenciadas pelos pais no pós-parto. Coimbra, Portugal: Mar da Palavra. * Escola Superior de Enfermagem de Coimbra, Unidade Científico-Pedagógica de Enfermagem de Saúde Materna e Obstetrícia [ana@esenfc.pt] ** Escola Superior de Enfermagem de Coimbra, Enfermagem de Saúde Materna, Obstetrícia e Ginecologia, Professora C