73 research outputs found

    NASA advanced design program: Analysis, design, and construction of a solar powered aircraft

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    Increase in energy demands coupled with rapid depletion of natural energy resources have deemed solar energy as the most logical alternative source of power. The major objective of this project was to build a solar powered remotely controlled aircraft to demonstrate the feasibility of solar energy as an effective, alternate source of power. The final design was optimized for minimum weight and maximum strength of the structure. These design constraints necessitated a carbon fiber composite structure. Surya is a lightweight, durable aircraft capable of achieving level flight powered entirely by solar cells

    Solar Powered Multipurpose Remotely Powered Aircraft

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    Increase in energy demands coupled with rapid depletion of natural energy resources have deemed solar energy as an attractive alternative source of power. The focus was to design and construct a solar powered, remotely piloted vehicle to demonstrate the feasibility of solar energy as an effective, alternate source of power. The final design included minimizing the power requirements and maximizing the strength-to-weight and lift-to-drag ratios. Given the design constraints, Surya (the code-name given to the aircraft), is a lightweight aircraft primarily built using composite materials and capable of achieving level flight powered entirely by solar energy

    O ato de amamentar: um estudo qualitativo

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    O objetivo do estudo foi analisar, de forma qualitativa, o conhecimento e percepção de um grupo de mulheres, bem como analisar os determinantes que influenciam a prática do aleitamento materno. Foi adotada a metodologia da pesquisa qualitativa, utilizando como referencial a teoria de representações sociais. Foram entrevistadas 27 gestantes, por um único entrevistador, durante o pré-natal e acompanhadas até o sexto mês do bebê, quando já estavam completamente desmamados. A análise compreensiva das falas permitiu verificar os fatores que levam a mãe a amamentar seus filhos, como "proteção do bebê" e "amor materno". Também foram verificados os motivos que levaram as mães a desmamarem seus filhos, sendo citados "a falta de leite"/"leite secou" e o "trabalho". Verificou-se, a partir das representações das mães, que mesmo que elas demonstrassem conhecimento sobre as propriedades do leite, não foi garantido o sucesso da prática de amamentação natural.This study aimed to perform a qualitative analysis of the knowledge and perception of a group of women, and to assess the determinants that influence breastfeeding. It adopted the qualitative research method, based on the theory of social representations. Twenty-seven pregnant women were interviewed by only one interviewer during prenatal period and the babies were accompanied until the sixth month after birth or until they were completely weaned. The comprehensive speech analysis allowed verifying factors that made mothers breastfeed their babies, like: "baby protection" and "mother's love". We also observed the reasons that made mothers wean their babies: "lack of milk" / "the milk dried" and "job". Through the mother's representations we could notice that even if they showed knowledge about properties and advantages of milk, it did not guarantee the successful natural breastfeeding practice

    Fatores associados à interrupção precoce do aleitamento materno: um estudo de coorte de nascimento em dois municípios do Recôncavo da Bahia, Brasil

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    Este estudo objetivou identificar a duração mediana e os fatores associados à interrupção precoce do aleitamento materno. Envolveu uma coorte de nascimento de 531 crianças acompanhadas até os dois anos de idade em dois municípios do Recôncavo da Bahia, Brasil. Utilizaram-se a análise de sobrevivência e o modelo multivariado de Cox. A duração mediana foi de 74,73, 211,25 e 432,63 dias, respectivamente, para o aleitamento materno exclusivo, misto complementado e total. A ausência materna ao pré-natal elevou em 173% (HR = 2,73; IC95%: 1,89-3,93) o risco de diminuir a duração do aleitamento materno exclusivo, em 83% (HR = 1,83; IC95%: 1,06-3,16) o risco da adoção do aleitamento misto complementado e em 38% (HR = 1,38; IC95%: 1,06-1,81) o risco da descontinuidade do aleitamento materno. O trabalho materno fora do domicílio e a área de residência urbana aumentaram o risco para interrupção precoce do aleitamento materno. A ampliação do acesso ao pré-natal e da rede de proteção às mães que trabalham fora do domicilio e àquelas que residem na área urbana poderia aumentar a duração da amamentação no Recôncavo da Bahia.This study aimed to identify the median duration of breastfeeding and associated factors in a cohort of 531 infants in two municipalities in the Recôncavo region, Bahia State, Brazil. Breastfeeding duration was estimated by survival analysis and its associations by the Cox ultivariate model. Median duration of exclusive breastfeeding, mixed breastfeeding with complementary feeding, and total breastfeeding was 74.73, 211.25, and 432.63 days, respectively. Lack of prenatal care increased the risk of shortening exclusive breastfeeding by 173% (HR = 2.73; 95%CI: 1.89-3.93), of adopting mixed breastfeeding with complementary feeding by 83% (HR = 1.83; 95%CI: 1.06-3.16), and of discontinuing breastfeeding entirely by 38% (HR = 1.38; 95%CI: 1.06-1.81). Both maternal employment and residence in an urban area increased the risk of early breastfeeding cessation. Expansion of access to prenatal care and the safety network for employed mothers living in urban areas could increase breastfeeding duration in the target region

    Frequency Characteristics of Magnetostriction in Electrical Steel Related to the Structural Vibrations

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