human structure interaction in pedestrian bridges a probabilistic approach

Abstract This paper deals with the quantification of the effects of human-structure interaction in the vertical direction for footbridges. Analyses are based on the study of a coupled system of the footbridge, modeled as a continuous dynamic system, and pedestrians, schematized as moving single-degree-of-freedom systems, characterized by random dynamic properties. The equivalent dynamic properties of the coupled system are estimated based on a state-space approach. The dimensionless parameters governing the problem are identified and numerical simulations are carried out varying such dimensionless parameters. Results of Monte Carlo simulations allow to quantify the effects of human-structure interaction on the dynamic properties of the footbridge, identifying the ranges of the governing dimensionless parameters where such effect is determinant

Sexual Dysfunctions of HIV-Positive Men: Associated Factors, Pathophysiology Issues, and Clinical Management

Sexual dysfunctions in HIV-positive men are associated with an increase in risky sexual behavior and decreased adherence to antiretroviral drug regimens. Because of these important public health issues, we reviewed the literature on the pathophysiology, associated factors and clinical management of sexual dysfunction in HIV-positive men. The goal was to investigate the current research on these issues. Literature searches were performed in June 2011 on PubMed, Web of Science, and PsycInfo databases with the keywords “AIDS” and “sexual dysfunction” and “HIV” and “sexual dysfunction”, resulting in 54 papers. Several researchers have investigated the factors associated with sexual dysfunction in HIV-positive men. The association between sexual dysfunction and antiretroviral drugs, particularly protease inhibitors, has been reported in many studies. The lack of standardized measures in many studies and the varying study designs are the main reasons that explain the controversial results. Despite some important findings, the pathophysiology of sexual dysfunction in the HAART era still not completely understood. Clinical trials of testosterone replacement therapy have shown the treatment to be beneficial to the improvement of sexual dysfunctions related to hypogonadism. However, there are not enough psychological intervention studies to make conclusions regarding the therapeutic effects of psychotherapy

Human-induced loading and dynamic response of footbridges in the vertical direction due to restricted pedestrian traffic

Despite extensive research in the field of human-induced vibration in the last twenty years, there is still lack of reliable load and response models to assess vibration serviceability of footbridges under human-induced excitation, especially with reference to crowded conditions. This paper aims to provide a reliable characterization of pedestrian-induced loading on footbridges in restricted traffic condition, and to compare the reliability of current guidelines and advanced spectral models in the serviceability assessment of footbridges with respect to vertical vibrations. Numerical simulations of restricted pedestrian traffic are carried out through an agent-based model, considering variable pedestrian densities and deck widths. The probability distribution of the step frequency and the power spectral density function of the modal force are obtained numerically. Based on the numerical results, a Modified Generalized Equivalent Spectral Model is proposed. Finally, two numerical examples are analyzed to assess the reliability of current guidelines and of the Modified Generalized Equivalent Spectral Model in the estimate of the maximum footbridge acceleration

Analyzing Tarsila do Amaral's paintings from a social semiotic perspective

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Comunicação e Expressão. Programa de Pós-Graduação em Letras/Inglês e Literatura Correspondente.Esta dissertação investiga três pinturas de Tarsila do Amaral, Carnaval em Madureira, Abaporú, e Operários a partir de uma análise no âmbito da semiótica social com o propósito de estudar como as artes visuais bem como outros tipos de comunicação visual transmitem significados relacionados com os aspectos sócio-culturais da sociedade em que são produzidos. O estudo enfatiza a importância da arte na história da humanidade e sua relação com paradigmas culturais desde a arte pré-histórica até a arte contemporânea. As obras de Tarsila do Amaral foram escolhidas como objeto de estudo desta dissertação com o objetivo de investigar a arte de uma pintora brasileira que se esforçou para conectar o Brasil ao Modernismo europeu no começo do século XX, mesmo tendo que enfrentar eventuais preconceitos que seu estilo de vanguarda pudesse causar. A análise visual teve como apoio a gramática visual de Kress and van Leeuwen (1996) a qual é baseada na gramática sistêmica funcional (SFL) de Halliday (1978,1994). Com esta base teórica, o estudo faz uma descrição do Contexto da cultura no qual Tarsila do Amaral estava inserida quando iniciou sua carreira de pintora e depois também descreve as estruturas (os significados Represetacionais, Interacionais e Composicionais) que operam nas três pinturas acima mencionadas. Esta análise contribuiu para a descoberta de importantes significados sócio-culturais inseridos nas pinturas de Tarsila do Amaral, tais como a presença do Modernismo e os problemas sociais relacionados com a industrialização no país. Outras áreas acadêmicas, além de lingüística, tais com História da Arte, História do Brasil e Artes Visuais foram usadas na pesquisa aqui desenvolvida num trabalho interdisciplinar. Os resultados sugerem: a) que as pinturas de Tarsila do Amaral (como qualquer tipo de comunicação visual) estão relacionadas com o contexto sócio-cultural da sociedade na qual foram produzidas e b) que o letramento visual pode, então, contribuir para que tenhamos uma melhor compreensão da sociedade contemporânea

Escrituras do grito em Antonin Artaud

Este texto decanta da experiência de escuta-leitura da obra de Antonin Artaud e recolhe, nas construções do poeta, efeitos de testemunho acerca de um tempo de soltura entre voz e palavra, quando o que emerge é o grito. Este estudo acerca da voz e das tentativas de escritura do inominável conduz a uma pergunta auxiliar sobre o corpo. Nessa composição, destaca-se, a partir dos fios da psicanálise, lalangue – articulador teórico que enlaça corpo e palavra, voz e escrita. É a partir de lalangue que o artigo se inclina em direção à obra de Artaud para percorrer a travessia do grito desde o vazio da voz desancorada da palavra em um momento de queda do sujeito para um espaço/tempo de endereçamento e existência – existência que se sustentará corporificada na obra de Artaud.This text arises from the listening-reading experience of the works of Antonin Artaud and brings together the testimony effects in the constructions of the poet about a moment of looseness between the voice and the word, giving rise to the scream. This study about the voice and attempts of writing the unspeakable leads to an accessory question about the body. In this structure, based on the psychoanalysis threads, lalangue – as a theoretical articulator encompassing body and word, voice, and writing – stands out. Based on lalangue the essay is directed to the work of Artaud to travel along the scream path from the emptiness of the unanchored voice of the word in a moment of fall of the subject to space/time of addressing and existence. An existence that will be supported and embodied in the work of Artaud

A green potentiometric method for the determination of the iodine number of biodiesel

AbstractIn this paper a green potentiometric method is proposed for the determination of the iodine number of biodiesel. The solvent used is simply a water–ethanol mixture (1:1v/v) and the reagent is iodine. The analytical procedure can be performed even without a laboratory hood as no iodine vapors are released if the method is done as indicated. The analytical results obtained with this procedure were compared with those from Wijs’ method. In order to strictly compare instrumental procedures potentiometry was also applied to the Wijs’ procedure. Also for comparison purposes a green visual method was applied. Statistical comparison of the four methods, through the paired Student’s t test and the F test of Snedecor showed excellent agreement among all of them

Thunderstorm gust response factor: General tendencies and sensitivity analysis

This paper aims to provide a sensitivity analysis of the thunderstorm gust response factor. The study is based on the extension of the gust response factor technique to the assessment of the maximum dynamic response of structures to thunderstorm outflows, starting from an evolutionary spectral model of the thunderstorm wind speed. The thunderstorm evolutionary spectral model depends on the modulating function of the slowly-varying mean speed, which is a function of two parameters, i.e. the background mean wind speed and the duration of the intense phase of the outflow. Starting from 129 full-scale thunderstorm records, the parameters of three different analytical models of the modulating function are extracted and a statistical analysis is carried out defining their range of variation. The dependence of the gust response factor on the analytical expression of the modulating function is studied as well as its sensitivity to the parameters of the function. Results show that the dependence of the gust response factor on the analytical expression of the modulating function is negligible, while it is very sensitive to the variation of the background wind and duration of the intense phase, especially for flexible and lowly-damped systems