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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Optimalizace světelných podmínek v budovách / Optimisation of light conditions in buildings

Vajkay, František January 2013 (has links)
Building physics as a branch of architecture must ensure an indoor comfort of each user and inhabitant of a building object. This involves, acoustics, indoor thermal conditions and among others also daylighting and artificial lighting of buildings. Light as a particle and an electromagnetic wave, is required by the different aspects of the human organism. It allows the living beings to see, influences skin and bones, the biorhythms, etc. Therefore, it is necessary for the engineering community to predict the correct illuminance and luminance levels acting insides. The thesis deals with such issues. More precisely, it assesses the quality of design tools and methodologies, either against CIE reference cases described in CIE 171/2006 and against real measurements done over the working plane of an indoor space located in the attic of Building D of the Institute of Building Structures, Faculty of Civil Engineering, Brno University of Technology, too. The tools tested throughout the solution of the dissertation did involve three computer programs: RADIANCE, WDLS v3.1 and WDLS v4.1, and one numerographical approach, namely the Daniljuk’s innovated methodology (sometimes even combined with the theories of BRS). In addition several software’s have had been created alongside the process assessment, just to mention the “RADIANCE Script”, “RADIANCE Data Evaluation Script” or “MuuLUX“. The later was written as a communication software allowing the connection of the KONICA-MINOLTA T10 illuminance meter to a computer with the aim of data collection while long term observation. The solution did also require the establishment of a measuring element for the determination of the light reflectance values of surfaces. The solutions, results and conclusions do describe how well did the design approaches deal while predicting the resulting awaited daylight factor levels in points over the working plane.
52

[en] MICROSCOPY OF BIOFILMS FORMED ON A METALLIC SUBSTRATE IN THE PRESENCE OF OILY FLUIDS IN STATIC AND DYNAMIC SYSTEMS / [pt] MICROSCOPIA DE BIOFILMES EM SUBSTRATO METÁLICO FORMADO EM SISTEMAS ESTÁTICO E DINÂMICO NA PRESENÇA DE FLUIDO OLEOSO

KARLA DE AVELLAR MOTA 12 January 2018 (has links)
[pt] Este trabalho teve por objetivo avaliar a morfologia de biofilmes, formados em superfície de aço API 5L X80 submetida a um fluido com baixo BSW (Basic Sediment Water), ou seja, baixo teor de água em óleo, através de análise por Microscopia Eletrônica de Varredura (MEV), determinar a cinética e quantificar os grupos bacterianos de formação destes biofilmes, e avaliar a biocorrosão causada por estes microrganismos. Foram realizadas alterações no protocolo original de preparo de amostras, com a finalidade de obter melhor definição das morfologias avaliadas. Realizaram-se estudos dinâmicos (looping) e em condições estáticas, com e sem a adição de agente biocida. Utilizando-se como fluido de processo o óleo coletado no terminal da Petrobras em Barra do Furado que tem como característica um BSW de aproximadamente 1 por cento de água. Para alcançar os objetivos descritos foram quantificadas bactérias sésseis (bactérias facultativas heterotróficas, bactérias precipitantes do ferro, bactérias anaeróbias heterotróficas e bactérias redutoras de sulfato) através da técnica do número mais provável (NMP). A intensidade do processo corrosivo foi avaliada através da análise dos pites formados nos cupons por microscopia óptica. A seqüência de fixação com alteração do protocolo inicial, permitiu uma melhor preservação estrutural do biofilme obtendo-se assim imagens com melhor resolução, tendo em vista que a fixação primária com glutaraldeído fixa principalmente proteínas pelo estabelecimento de ligações divalentes com grupamento amino, e a pós-fixação em tetróxido de ósmio reage com os lipídios. Quanto a cinética, observou-se também que na presença de fluido oleoso, a formação do biofilme só é detectada após 15 dias de exposição. A adição do agente biocida inibiu o crescimento do biofilme, não sendo detectada a presença de células cultiváveis após 7 dias em contato com o fluido contendo o agente químico. / [en] This study aims to evaluate the morphology of biofilms formed on the surface of API 5L X80 steel exposed to a low BSW (Basic Sediment Water) fluid comprising oil of a low water content. The analisys was performed using scanning electron microscopy (SEM) in order to determine the formation kinetics, to quantify and identify the bacterial groups present as the film formed, and to evaluate the biocorrosion caused by these organisms. Modifications were made to the original sample preparation protocol, in order to better define the film morphologies. Studies were undertaken applying either static or dynamic (looping) conditions, bith with and without the addition of biocides. The process fluid used was oil collected from the Petrobras Barra do Furado Terminal, characterized by its 1 percent BSW. The evaluation was performed quantifying the sessile bacteria present in the film (heterotrophic bacteria, iron bacteria, anaerobic bacteria e sulphate reducing bacteria) via the Most Probable Number (MPN) technique. The intensity of the corrosion process was determined by the analysis of pits forme in the testpieces, by optical microscopy. The application of a sample fixation sequence, in addition to modifications of the inicial sample preparation protocol, permitted the improved preservation of the biofilm structures, thereby permitting higher resolution images. The primary fixing agent, containing gluteraldehyde, principally fixes proteins, by establishing divalent bonds with amino groups, while the post-fixation stage with osmium tetroxide invloves reactions with lipid groups.With regard to the film deposition kinetics, it was observed that biofilm formation could only be detected after 15 day s exposure to the oily fluid. The addition of a biocide, inhibited the growth of the film, no cultivatable cells being present after 7 days contact with the treated fluid.
53

Cultivo do algodoeiro irrigado sob adubação orgânica nitrogenada - potencial fitorremediador. / Cotton crop cultivation in organic nitrogen fertilization - potencial phytoremediator.

SANTOS, Joelma Sales dos. 17 September 2018 (has links)
Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-09-17T20:57:43Z No. of bitstreams: 1 JOELMA SALES DOS SANTOS - TESE PPGEA 2012..pdf: 13860742 bytes, checksum: fac37c1ab0eb02e62c3c72dbd0f37041 (MD5) / Made available in DSpace on 2018-09-17T20:57:43Z (GMT). No. of bitstreams: 1 JOELMA SALES DOS SANTOS - TESE PPGEA 2012..pdf: 13860742 bytes, checksum: fac37c1ab0eb02e62c3c72dbd0f37041 (MD5) Previous issue date: 2012-02 / CNPq / A reutilização de resíduos na agricultura tem-se tornado uma alternativa promissora e viável, de vez que pode substituir a adubação química, proporcionando um elevado aporte de nutrientes às plantas, o que possibilita a redução dos custos de produção. Neste sentido, o objetivo do trabalho foi avaliar o uso de composto orgânico oriundo de lixo doméstico e a irrigação com água residuária doméstica tratada no desenvolvimento, produção e qualidade da fibra do algodoeiro, bem como seu potencial em absorver os metais zinco e cobre. Para isto, as plantas foram cultivadas em ambiente protegido pertencente à Universidade Federal de Campina Grande, município de Campina Grande, PB. O delineamento experimental foi em blocos casualizados em esquema fatorial 6x2, com 3 repetições; as 6 doses de nitrogénio disponível em composto de resíduo sólido foram (0, 60, 100, 140, 180 e 220 kg de N ha'1) e 2 tipos de água (água potável e água residuária doméstica tratada). Verilicou-se que as doses de nitrogénio e os tipos de água utilizados não influenciaram significativamente, no que diz respeito ao desenvolvimento, à produção e qualidade da fibra do algodoeiro BRS 286, a fibra produzida por esta cultivar se encontra dentro dos parâmetros aceitáveis pela indústria têxtil. As plantas de algodão se mostraram mais eficientes na absorção e translocação do zinco quando irrigadas com água residuária doméstica tratada. A adubação orgânica oriunda da compostagem de lixo urbano e a irrigação residuária doméstica tratada, podem substituir a adubação química no cultivo de algodoeiro cultivar BRS 286. / The reuse of waste in agriculture has become a viable and promising alternative, since it can replace chemical fertilizer, providing a high input of nutrients to plants, which enables the reduction of costs production. In this sense, the objective was to evaluate the use of compost derived from household waste and irrigation with treated domestic wastewater in the development, production and quality of cotton fiber, as well as its potential to absorb the metais zinc and copper. For this, the plants were grown in a greenhouse belonging to the Federal University of Campina Grande, Campina Grande, Paraíba state. The experimental design was a randomized block in 6 x 2 factorial with three replicates, and six doses of nitrogen available in compost solid waste were (0, 60, 100, 140, 180 and 220 kg N ha"1) and two types of water (drinking water and treated domestic wastewater). It was found that the nitrogen and the type of water used had no significant effect, as regards the development, production and quality of cotton fiber BRS 286, the fiber is produced by cultivating parameters is within the acceptable industry textiles. The cotton plants were more efficient in uptake and translocation of zinc when irrigated with treated domestic wastewater. The organic fertilizer coming from the composting of urban waste and treated domestic wastewater irrigation can replace chemical fertilizers in the cultivation of cotton cultivar BRS 286.
54

[en] ANALYZE OF BIOFILM FORMATION KINETIC ON API 5L X80 LONGITUDINAL WELDS IN DYNAMIC FLOW SYSTEM / [pt] ANÁLISE DA CINÉTICA DE FORMAÇÃO DE BIOFILMES EM JUNTA SOLDADA LONGITUDINAL DE AÇO API 5L X80 EM SISTEMA DINÂMICO

27 October 2021 (has links)
[pt] A Corrosão Influenciada por Microrganismos (CIM) ou biocorrosão é reconhecida como um dos fenômenos causadores de inúmeros problemas nas indústrias de petróleo e gás, pois causa sérios danos ao material reduzindo sua vida útil. Neste trabalho foram avaliados os efeitos da biocorrosão caracterizado pela cinética de formação de biofilme em uma junta soldada longitudinal de aço API X80 obtida pelo processo de arco submerso (SAW). Durante o processo de soldagem forma-se uma região com características microestruturais distintas do metal de base e do metal de adição, denominada de zona termicamente afetada (ZTA). Assim essa zona poderá ter uma adesão microbiana diferenciada, visto que diferenças superficiais em um material, seja por natureza química ou física, podem limitar ou facilitar a adesão microbiológica. Por esse motivo foi realizado um estudo comparativo entre a cinética da formação de biofilme na junta soldada de um aço API X80. Também foi avaliada a influência das características físicas da superfície na adesão microbiana utilizando dois tipos de superfície: com a rugosidade original e polido com pasta de diamante com granulação de 6μm. Estas superfícies foram expostas ao fluido de processo (água do mar da Baía de Guanabara) em um sistema dinâmico. Foram realizadas tanto a quantificação microbiana, como também a quantificação dos ácidos orgânicos, sulfato depletado e ferro total para avaliar os nutrientes disponíveis e a bioatividade das reações bacterianas. A rugosidade superficial e o biofilme formado foram caracterizados morfologicamente e a sua presença correlacionada com a formação de pites. / [en] The Microbiologically Influenced Corrosion (MIC) or bio-corrosion is recognized as one of the phenomena that cause a lot of problems in petroleum and gas industries, because it causes serious damages to the materials, reducing its life cycle. This study evaluated the effects of bio-corrosion characterized by the biofilm formation kinetics in longitudinal welds of API 5L X80 steel obtained by the process of submerged arc welding (SAW). During the welding process a region with different microstructural characteristics of the base metal and weld metal is formed, called heat affected zone (HAZ). Thus this zone can have a differentiated microbial adhesion since the different surfaces of a material, either by chemical and physical nature, can limit or facilitate the microbial adhesion. For this reason a comparative study of biofilm formation kinetic on the welded joint was conducted. The influence of the physical characteristics of the surface in microbial adhesion was also evaluated using two kinds of surface: steel with real roughness and steel polished with diamond paste with grain size of 6 μm. These surfaces were exposed to the process fluid (Guanabara Bay seawater) in a dynamic flow system. The microbial quantification was held. Organic acids, depleted sulfate and total iron were also measured to evaluate the available nutrients bioactivity of bacterial reactions. Surface roughness and biofilm were characterized morphologically and correlated with pitting formation.
55

Vliv dýchání na barorecepční reflex / Influence of breathe to baroreceptor reflex

Humpolík, Tomáš January 2010 (has links)
This Master's thesis deals with the influence of breathe to baroreceptor reflex. The first chapter is focused on measuring of blood pressure, in reference to later used method. In the second part is detailed analysis and explanation of term baroreflex, relationship between frequency spectra of systolic blood pressure, heart rate and breathing, mechanisms of regulation of blood pressure and heart rate variability. Third chapter deals with possible ways, how to analyze data, which are needed for estimation of baroreflex sensitivity, analyze of heart rate variability and estimation of power spectral density. Next parts of this thesis is paid attention to technical equipment and methods of acqusition of data, using this equipmnent. Part of this work is also software application, which makes possible from the recorded data estimate baroreflex sensitivity.
56

An analysis of the relationship between psychosocial safety climate and the work-school-interface for non-traditional students in South Africa

April, Kelly 12 January 2022 (has links)
The growth of a country's economy is highly dependent on the levels of skills available in that country. South Africa has a stark shortage of skilled individuals due to an inadequate and failing education system (Horwitz, 2013). As a response to this problem the South African government actively incentivises organisations to develop the skillset of their employees in order to build a strong economy, improve job creation and promote social development (Department of Higher Education and Training, 2019). It is therefore important that all stakeholders involved yield a return on this investment. It is also a global phenomenon that an increasing number of fulltime employees are also engaging in formal further studies due to the rapid changes in the labour market. For example, advancements in technology have had a major impact on traditional business models and the roles, and skills needed. These employees are referred to as non-traditional students and are the subject of this study. Research shows that trying to manage both work and school simultaneously can cause psychological strain for non-traditional students (Adebayo et al., 2008). The psychosocial safety climate (PSC) is an emerging construct which refers to the shared perceptions regarding policies, practices and procedures designed to protect the psychological health of employees (Dollard et al., 2012). This study builds on existing research in the work - school interface by investigating its application within the South African context. Participants in this research (n=127), comprised of non-traditional students (n=40) and employees who are not engaged in further studies (n=87). Correlation analysis demonstrated that PSC had a positive relationship with work school facilitation (WSF) and a negative relationship with work school conflict (WSC). It was further confirmed that job control (JC) mediated the relationship between PSC and WSF and that PSC mediated the relationship between JC and WSF. These findings show that PSC is an antecedent to the work school interface in that it promotes the positive outcomes of studying while working (work school facilitation). It further demonstrates that PSC also reduces the negative outcomes (work school conflict). This study confirmed that the working environment plays a crucial role in the work school interface and introduces PSC as a construct South African organisations should be concerned with and make a priority, based on the resources it provides employees, more especially their non-traditional students. This study's findings will add to the existing body of research and provide practical insights for enhancing the PSC application within South African organisations who have non-traditional students.

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