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Análise e desempenho sísmico de um pórtico metálico de travessas inclinadas através de análises não-lineares

Braz César, M.T.; Cachim, Paulo
Fonte: Instituto Politécnico de Bragança Publicador: Instituto Politécnico de Bragança
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
25.92%
O principal objectivo deste artigo consiste na aplicação de diversas metodologias de análise não-linear de estruturas para avaliar o desempenho sísmico de pórticos metálicos de aço utilizados na construção de pavilhões industriais do tipo roof pitched portal frames. Para atingir este objectivo foi analisado um pórtico com 20m de vão com o recurso ao programa de cálculo automático MIDASCivil utilizando uma análise estática não-linear (ou pushover) e uma análise dinâmica não-linear para determinar a resposta da estrutura. Com base neste estudo pretende-se estimar a capacidade dissipativa desta estrutura e quantificar a resposta não-linear para avaliar o seu desempenho sísmico.

Reliability of Portal Frames with Interacting Stress Resultants

Simões, Luis
Fonte: ASCE Publicador: ASCE
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
25.92%

Reliability of Portal Frames with Discrete Design Variables

Simões, Luis
Fonte: Springer Verlag Publicador: Springer Verlag
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
25.92%

Reliability-based plastic synthesis of portal frames

Simões, Luis
Fonte: Gordon and Breach Science Publishers Publicador: Gordon and Breach Science Publishers
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
25.92%

Reliability of Portal Frames with Interacting Stress-resultants - Closure

Simões, Luis
Fonte: ASCE Journals Publicador: ASCE Journals
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
25.92%

Ligações viga-pilar de estruturas de concreto pré-moldado: análise com ênfase na deformabilidade ao momento fletor; Precast concrete beam-to-column connections: emphasis on the deformability analysis

Miotto, Anamaria Malachini
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 20/12/2002 PT
Relevância na Pesquisa
46.27%
No presente trabalho foram estudadas duas ligações viga-pilar de estruturas de concreto pré-moldado com ênfase na deformabilidade ao momento fletor. A primeira é muito utilizada em galpões com sistema estrutural de pórticos para telhado com duas águas. A segunda é utilizada em estruturas de edifícios com múltiplos pavimentos. Foram realizados ensaios físicos em dois modelos de cada tipo de ligação. Com base nos resultados experimentais, foram propostos modelos analíticos, baseados no Método dos Componentes, e realizadas simulações numéricas, baseadas no Método dos Elementos Finitos, através dos quais determinou-se a curva momento-rotação das ligações em estudo. As curvas momento rotação teóricas, para as duas ligações estudadas, ficaram bastante próximas das experimentais. De acordo com os resultados, pode-se dizer que a primeira ligação teve um comportamento próximo ao de uma ligação perfeitamente rígida. Isso porque, para uma estrutura típica, ela transmitiu mais de 90% do momento equivalente ao de uma estrutura monolítica. A segunda ligação também garantiu uma boa transferência de momento fletor. Observou-se que, ao considerar a semi-rigidez dessa ligação na análise estrutural, há uma redução significativa no momento na base dos pilares mais solicitados...

Comunicação e literacia digital na internet: estudo etnográfico e análise exploratória de dados do Programa de Inclusão Digital AcessaSP - PONLINE; Communication and Digital Literacy on Internet: an etnographic and exploratory study of digital divide Brazilian program AcessaSP Ponline.

Capobianco, Ligia
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 14/04/2010 PT
Relevância na Pesquisa
25.92%
Estudo sobre a utilização das ferramentas que compõem o universo das tecnologias de comunicação e informação (TICs), principalmente a Internet, no contexto de políticas públicas no Brasil, com foco no programa de inclusão digital do governo do estado de São Paulo, AcessaSP. O estudo baseia-se na análise dos resultados da PONLINE pesquisa on-line realizada anualmente com usuários do programa AcessaSP. Em primeiro lugar, delineou-se o panorama histórico que propiciou a evolução crescente das TICs a partir da Segunda-Guerra Mundial. Nesse contexto de inovações, surgiu a Internet e a WWW que formam a rede das redes. A Internet refere-se tanto à estrutura física de transmissão, armazenamento e recepção de informações como ao uso público para a comunicação. Em seguida, foram abordadas as principais teorias sobre os temas: sociedade da informação, sociedade em rede, cibercultura, inclusão digital e literacia digital, para esclarecer a diferença entre os assuntos e delimitar o âmbito de abrangência de cada um. A coleta de dados concentrou-se na análise das pesquisas PONLINE, dos anos de 2003 a 2008 que estão disponíveis no portal do Programa AcessaSP. Os dados das pesquisas PONLINE foram avaliados por meio de técnicas de análise estatística e os resultados foram apresentados em gráficos e tabelas. As técnicas aplicadas em estudos etnográficos possibilitaram a análise e interpretação dos depoimentos dos respondentes das pesquisas. Os dados foram selecionados para revelar características da utilização da Internet para comunicação...

Análise estrutural de galpões atirantados de concreto pré-moldado; Structural analysis of sheds with tied portal frames of precast concrete

Santos, Andreilton de Paula
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 08/06/2010 PT
Relevância na Pesquisa
66.57%
Os galpões de concreto pré-moldado, formados por pórticos atirantados, são muito utilizados, no Brasil. Porém, para o projeto dessas estruturas, a bibliografia é limitada. Além disso, vários critérios de projeto são adaptados dos relativos a estruturas de concreto moldado no local e de múltiplos pavimentos. O objetivo deste trabalho é contribuir para a análise desse tipo de estrutura, introduzindo conceitos que dificilmente são considerados na prática, tais como: rigidez da ligação viga-pilar, análise não-linear física e geométrica, deformação excessiva e fluência. A pesquisa foi desenvolvida por meio de análises estruturais, usando modelos de galpões comuns na prática. Cada conceito citado anteriormente foi analisado em exemplos. A rigidez da ligação viga-pilar foi avaliada com base no parâmetro de restrição à rotação, 'alfa'R. A não-linearidade física (NLF) do concreto foi considerada pelo método de Branson. Para a não-linearidade geométrica (NLG), foram utilizados os parâmetros 'alfa' e o processo P.'delta'. A deformação excessiva, incluindo a fluência, foi discutida tendo em conta os aspectos normativos. Constatou-se que a ligação viga-pilar pode ter comportamento semi-rígido em alguns casos...

On Nonlinear Dynamics and Control of A Particular Portal Frame Foundation Model, Excited by a Non-Ideal Motor

Balthazar, José Manoel; Felix, Jorge Luis Palacios; Brasil, Reyolando Manoel Lopes Rabelo da Fonseca
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 371-378
ENG
Relevância na Pesquisa
46.41%
The nonlinear dynamic response and a nonlinear control method of a particular portal frame foundation for an unbalanced rotating machine with limited power (non-ideal motor) are examined. Numerical simulations are performed for a set of control parameters (depending on the voltage of the motor) related to the static and dynamic characteristics of the motor. The interaction of the structure with the excitation source may lead to the occurrence of interesting phenomena during the forward passage through the several resonance states of the systems. A mathematical model having two degrees of freedom simplifies the non-ideal system. The study of controlling steady-state vibrations of the non-ideal system is based on the saturation phenomenon due to internal resonance.

Amorphous silicon detector panel damage: correlating physical parameters to clinical usability

Moura, Filipe Martins Garcia de
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2008 ENG
Relevância na Pesquisa
16.56%
Tese de mestrado em Biofísica (Física Médica e Engenharia Biomédica), apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2008; Electronic Portal Imaging Devices (EPIDs) currently used in radiation therapy always suffer from high energy particles, which induce a significant reduction in image quality by increasing the system noise, and decreasing the sensitivity of the active pixel matrix. The performance of these devices needs periodical tests to check the reliability of the imaging system, and the acquired clinical data. The method should be able to quantify the variation of specific EPID physical parameters in-Time, and its correlation between the damage and the clinical usability. The standard gold Quality Assurance (QA) procedures for testing EPID response, consists on the evaluation of commercial phantoms, e.g. QC-3V phantom (QC3) which can provide image physical parameters for noise, contrast and spatial resolution based on small EPID areas, typically 1cm2. For this study we tested four Elekta iViewGT amorphous silicon EPIDs(a-Si EPIDs) with operational ages between 1 and 33 months. New approaches were introduced as alternatives for the gold standard on megavoltage image quality control, by looking for lifeline tendencies and investigate the QC3 under non-standard conditions. The subjective quality evaluation of clinical portal images was performed by a questionnaire to the expertise of five clinical users. The images were taken for thorax and pelvic locations on the same lifetime moment to achieve better correlations in time. The relative modulation transfer function that measures the spatial resolution was found to be more dependent on the blurring effects due to the linear accelerator (Linac) finite focal spot size...

Cloning and Analysis of the Capsid Morphogenesis Genes of Pseudomonas aeruginosa Bacteriophage D3: Another Example of Protein Chain Mail?

Gilakjan, Zeynab A.; Kropinski, Andrew M.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Publicado em /12/1999 EN
Relevância na Pesquisa
16.09%
The terminal DNA restriction fragments (PstI-D and -B) of Pseudomonas aeruginosa bacteriophage D3 were ligated, cloned, and sequenced. Of the nine open reading frames in this 8.3-kb fragment, four were identified as encoding large-subunit terminase, portal, ClpP protease, and major head proteins. The portal and capsid proteins showed significant homology with proteins of the lambdoid coliphage HK97. Phage D3 was purified by CsCl equilibrium gradient centrifugation (ρ = 1.533 g/ml), and sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed six proteins with molecular masses of 186, 91, 79, 70, 45, and 32 kDa. The pattern was unusual, since a major band corresponding to the expected head protein (43 kDa) was missing and a significant amount of the protein was retained in the stacking gel. The amino terminus of the 186-kDa protein was sequenced, revealing that the D3 head is composed of cross-linked 31-kDa protein subunits, resulting from the proteolysis of the 43-kDa precursor. This is identical to the situation observed with coliphage HK97.

Quantitative Portal Vein Velocity of Liver Cancer Patients with Transcatheter Arterial Chemoembolization on Angiography

Ho, Yung-Jen; Chang, Mu-Bai; Lin, Yang-Hsien; Yao, Chun-Hsu; Huang, Tzung-Chi
Fonte: The Scientific World Journal Publicador: The Scientific World Journal
Tipo: Artigo de Revista Científica
Publicado em 31/07/2012 EN
Relevância na Pesquisa
26.28%
Objective. We applied optical flow method (OFM) to quantify relative velocities of blood flow using digital subtraction angiography (DSA) in the vascular analysis of hepatocellular carcinoma (HCC) patients who underwent transarterial chemoembolization (TACE) treatment. Methods. A total of 40 HCC patients treated by TACE were analyzed in this study. DSA imaging with a 12-inch field of view, 1024 × 1024 pixels and 4 frames/second was acquired. OFM developed for motion estimation is applied for blood flow estimation. Two acrylic phantoms were built to validate the method. Results. The relationship between the OFM and Doppler measurements was found linear with R2 = 0.99 for both straight and curved tube phantoms. Quantitative blood flow distribution images of the portal vein region were presented. After TACE, the minimum, maximum and mean velocities in the portal vein all decreased (P < 0.05). Additionally, the velocity in the portal vein is significantly lower with a higher Child-Pugh score (P < 0.01). Conclusions. The present technique provides add-on quantitative information of flows to DSA and the hemodynamic analysis in relative quantifications of blood flow in portal vein of hepatocellular carcinoma patients using DSA.

Nonlinear Earthquake Analysis of Reinforced Concrete Frames with Fiber and Bernoulli-Euler Beam-Column Element

Karaton, Muhammet
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: Artigo de Revista Científica
Publicado em 22/01/2014 EN
Relevância na Pesquisa
26.09%
A beam-column element based on the Euler-Bernoulli beam theory is researched for nonlinear dynamic analysis of reinforced concrete (RC) structural element. Stiffness matrix of this element is obtained by using rigidity method. A solution technique that included nonlinear dynamic substructure procedure is developed for dynamic analyses of RC frames. A predicted-corrected form of the Bossak-α method is applied for dynamic integration scheme. A comparison of experimental data of a RC column element with numerical results, obtained from proposed solution technique, is studied for verification the numerical solutions. Furthermore, nonlinear cyclic analysis results of a portal reinforced concrete frame are achieved for comparing the proposed solution technique with Fibre element, based on flexibility method. However, seismic damage analyses of an 8-story RC frame structure with soft-story are investigated for cases of lumped/distributed mass and load. Damage region, propagation, and intensities according to both approaches are researched.

Clostridium perfringens bacteriophages ΦCP39O and ΦCP26F: genomic organization and proteomic analysis of the virions

Seal, Bruce S.; Fouts, Derrick E.; Simmons, Mustafa; Garrish, Johnna K.; Kuntz, Robin L.; Woolsey, Rebekah; Schegg, Kathleen M.; Kropinski, Andrew M.; Ackermann, Hans-W.; Siragusa, Gregory R.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
16.27%
Poultry intestinal material, sewage and poultry processing drainage water were screened for virulent Clostridium perfringens bacteriophages. Viruses isolated from broiler chicken offal washes (O) and poultry feces (F), designated ΦCP39O and ΦCP26F, respectively, produced clear plaques on host strains. Both bacteriophages had isometric heads of 57 nm in diameter with 100-nm non-contractile tails characteristic of members of the family Siphoviridae in the order Caudovirales. The double-strand DNA genome of bacteriophage ΦCP39O was 38,753 base pairs (bp), while the ΦCP26F genome was 39,188 bp, with an average GC content of 30.3%. Both viral genomes contained 62 potential open reading frames (ORFs) predicted to be encoded on one strand. Among the ORFs, 29 predicted proteins had no known similarity while others encoded putative bacteriophage capsid components such as a pre-neck/appendage, tail, tape measure and portal proteins. Other genes encoded a predicted DNA primase, single-strand DNA-binding protein, terminase, thymidylate synthase and a transcription factor. Potential lytic enzymes such as a fibronectin-binding autolysin, an amidase/hydrolase and a holin were encoded in the viral genomes. Several ORFs encoded proteins that gave BLASTP matches with proteins from Clostridium spp. and other Gram-positive bacterial and bacteriophage genomes as well as unknown putative Collinsella aerofaciens proteins. Proteomics analysis of the purified viruses resulted in the identification of the putative pre-neck/appendage protein and a minor structural protein encoded by large open reading frames. Variants of the portal protein were identified...

Ferramenta para avaliação da presença de práticas de simbiose industrial em uma rede de empresas

Saraceni, Adriana Valélia
Fonte: Ponta Grossa Publicador: Ponta Grossa
Tipo: Dissertação de Mestrado
POR
Relevância na Pesquisa
16.09%
The main objective of this research was to develop a tool for assessing the presence of Industrial Symbiosis practices in na industrial cluster, based on the concepts of Industrial Symbiosis found in the literature. For this, were conceived a variety of steps to form theoretical framework of this research, and, for the development of the proposed methodology. In order to form the bibliographic portfolio, this research initial steps were based on the instrument ProKnow-C (Knowledge Development Process–Constructivist). This procedure was performed with support of ISI Web of Knowledge portal and carried out in two categories of classification: Engineering, Environmental and Engineering, Industrial. Based on this differentiated systematic review, the variables of Industrial Symbiosis were identified. The results obtained by this procedure allowed the development of the theoretical model. After identificatifying the variables, a methodology based on fuzzy logic was applied and directed to the researchers of the subject for assigning weights of the variables of Industrial Symbiosis. Thus, it was possible to extract indicators of intensity of the interrelationships, these, needed in the analysis of the level of development of each of the correlations between the variables. In possession of the variables and their indicators...

Molecular analysis of acute and chronic duck hepatitis B virus (DHBV) infections in ducks.

Low, Huey Chi
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2012
Relevância na Pesquisa
16.18%
The hepadnavirus family contains two genera, Orthohepadnaviruses that infect mammals and Avihepadnaviruses that infect birds. The most thoroughly studied members of the hepadnavirus family include hepatitis B virus (HBV), which infects humans and chimpanzees, woodchuck hepatitis virus (WHV), which infects woodchucks, and duck hepatitis B virus (DHBV), which infects ducks. All hepadnaviruses have similar genome structure and organisation of the open reading frames on their genome, and also show extensive nucleotide sequence homology within, but not between, genera. All hepadnaviruses primarily infect hepatocytes and have similar infection outcomes in their natural hosts. The outcome of hepadnavirus infection can be divided into either acute, with successful clearance of infection from the host and establishment of immune control, or chronic, where infection is not cleared, resulting in persistent lifelong infection that is linked to various forms of liver disease. The mechanisms involved in immune clearance of hepadnavirus infections are poorly understood. It has been hypothesised that virus DNA and proteins are, 1) cleared from the liver cytolytically by killing of the infected hepatocytes, or 2) can be destroyed noncytolytically by cytokines...

Public-Private Partnerships in e-Government : Knowledge Map

Institute for Public-Private Partnerships
Fonte: World Bank, Washington, DC Publicador: World Bank, Washington, DC
Tipo: Publications & Research :: Working Paper; Publications & Research
ENGLISH; EN_US
Relevância na Pesquisa
16.18%
The last few years have seen considerable research and applications in the areas of Public-Private Partnerships (PPPs) and electronic-government (e-government). Rather than attempting to redefine these areas, or considering them as two distinct paradigms, the authoring of this Knowledge Map (KM) and its accompanying Handbook is an effort to bring a certain degree of convergence, and see whether PPPs are, or can be, effective instruments for e-government initiatives in a country. The increasing emphasis on e-government is often directly attributed to the fact that the use and application of Information and Communication Technologies (ICT) are now commonly accepted as powerful engines for economic growth. As governments embrace ICT as a means to accelerate the development process this also becomes foremost in the reforms agenda, and in their delivery of services to citizens, businesses, civil society organizations, and other government agencies. This 'public-private partnerships in e-government: knowledge map' is designed to be an introductory guide to PPPs for public officials responsible for e-government initiatives. It is for those who are seeking to enhance the quality...

Comportamento dinâmico não-linear em fenômenos de colheita de energia usando dispositivos baseados em materiais piezoelétricos em estruturas aporticadas

Rocha, Rodrigo Tumolin
Fonte: Universidade Estadual Paulista (UNESP) Publicador: Universidade Estadual Paulista (UNESP)
Tipo: Dissertação de Mestrado Formato: 72 f. : il.
POR
Relevância na Pesquisa
25.92%
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES); Pós-graduação em Engenharia Mecânica - FEB; Recentemente o interesse e a pesquisa sobre a colheita de energia têm aumentado substancialmente. Muitos pesquisadores têm concentrado seus esforços em encontrar a melhor configuração para estes sistemas e para otimizar sua potência de saída. No processo de colheita de energia, a energia elétrica é obtida através da conversão de energia mecânica criada por uma fonte de vibração do ambiente por meio de um transdutor, por exemplo, um fino filme piezocerâmico. Essa fonte de vibração é, por exemplo, uma barra sofrendo alguma força mecânica capaz de gerar certa vibração na estrutura, como pontes onde passam veículos, um trem, ou até mesmo pessoas que podem causar vibrações na estrutura. Diferentes mecanismos de acoplamento eletromecânico têm sido desenvolvido para dispositivos de colheita de energia, existindo um interesse particular na utilização de modelos que transformam essas vibrações mecânicas em corrente elétrica utilizando um elemento piezoelétrico. Estruturas aporticadas, como por exemplo, uma ponte onde passam veículos ou ferrovias podem conter ressonâncias internas entre seus modos de vibrar...

Creating grid resources for use in undergraduate coursework

Huffman, John; Repasky, Richard; Rinkovsky, Joseph
Fonte: Grid Computing Environments (GCE) Publicador: Grid Computing Environments (GCE)
Tipo: Proceedings
EN_US
Relevância na Pesquisa
26.09%
Rendered animations are a significant part of many student and research projects being done at Indiana University. Typically the rendering process is very computationally intensive, but it is allocated minimal computing resources. By creating a Condor pool out of all student computing labs we have created a large scale, homogeneous grid resource dedicated to the single purpose of rendering. By implementing a web portal based interface to submit and monitor rendering jobs the rendering system becomes independent of the end users architecture, OS, and even rendering package being used. This allows for a “learn once, run often” architecture despite the highly complex distributed computational backend. The web interface allows users to submit jobs with the needed parameters, monitor the progress of the job, and display finished frames of the animation. When the job finishes the render system notifies the user and will present a web based preview of the final movie, allowing the user to quickly assess the quality of the rendered results. The modular nature of the render system allows for easy upgrade and additions to the rendering packages offered. New rendering packages can typically be added within 24 hrs, without any changes to the user interface or workflow.; "Creating grid resources for use in undergraduate coursework...

Accounting for moment-rotation behaviour of connections in portal frames

Albertyn,H L; Haas,T N; Dunaiski,P E
Fonte: Journal of the South African Institution of Civil Engineering Publicador: Journal of the South African Institution of Civil Engineering
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
Relevância na Pesquisa
46.7%
Portal frames are steel structures used to construct industrial buildings. Conventional analysis techniques used by practising engineering professionals assume that the eave, ridge and base connections are either infinitely rigid or perfectly pinned. This approach leads to less accurate analysis of the displacement behaviour of portal frames when subjected to external loading. Portal frames must therefore be analysed with rotational springs at all connections to yield accurate displacement behaviour. This investigation focused on determining the accuracy and economic feasibility of modelling portal frame connections with rotational springs. The rotational spring stiffnesses of all connections were required before the portal frame could be analysed in a second-order two-dimensional non-linear analysis. The rotational spring stiffnesses unique to each connection were determined from the moment-rotation behaviour obtained from a series of finite element analysis simulations of each connection. Thereafter these stiffnesses were used to determine the vertical and horizontal displacements of the portal frame. These displacements were compared with experimental test results. The reasons for the discrepancies between the numerical and experimental results were investigated through a sensitivity analysis. The findings suggest that it is not computationally feasible to analyse portal frames with rotational springs...