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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.
161

"Hepatite C: transmissão entre casais" / Hepatitis C: transmission between couples.

Norma de Paula Cavalheiro 26 March 2004 (has links)
RESUMO Cavalheiro, NP. Hepatite C: transmissão entre casais. São Paulo, 2004. 111p. Tese (Doutorado) - Faculdade de Medicina, Universidade de São Paulo. Introdução: A ocorrência e eficiência da transmissão sexual do VHC na ausência de outros fatores de risco ainda é muito controversa. Foram investigados e analisados 24 casais, ambos cônjuges infectados com o VHC. Destes, 22 apresentaram o mesmo subtipo viral e a análise filogenética de parte da região NS5b mostrou altos índices de homologia nas seqüências entre os vírus dos casais infectados. Objetivo: Análise da transmissão da Hepatite C entre casais heterossexuais. Método: O estudo recrutou 45 casais. Destes, 24 foram selecionados e incluídos na pesquisa, com diagnóstico clínico e laboratorial para a Hepatite C crônica. A infecção foi diagnosticada por testes imunoenzimáticos de terceira geração e pela presença da partícula viral circulante detectada pela PCR. As amostras de sangue foram coletadas entre os anos de 1999 e 2002. Foram seqüenciadas partes das regiões 5’NC e NS5b do VHC, para determinação dos subtipos virais. Os testes utilizados para as PCRs estão disponíveis para pesquisa e foram respectivamente TRUGENE 5’NC Test (Bayer Health Care Diagnostics, Tarrytown, NY, USA) e Titan One Tube RT-PCR Kits (Roche Molecular, Mannheim, Germany). Para as PCRs dos seqüenciamentos foi utilizado o kit CLIP sequencing test (Bayer Health Care Diagnostics, Tarrytown, NY, USA). As seqüências foram analisadas com o sistema de seqüenciamento Open Gene DNA, software na Versão 3.1, biblioteca específica (Bayer Health Care Diagnostics, Tarrytown, NY, USA). Para o alinhamento das seqüências, referentes a região NS5b, foi utilizado o programa Clustal W (Clustal W Multiple Sequence Alignment Program, v1.7, June 1997) e a árvore filogenética foi gerada pelo método Neighbor Joining. Um questionário padrão e entrevistas foram usados para coleta de dados sobre fatores de risco para aquisição da doença e comportamento sexual. Os pacientes desta pesquisa foram recrutados no Ambulatório de Hepatite do Hospital das Clínicas da Universidade de São Paulo e Ambulatório de Hepatite do Hospital Guilherme Álvaro, da cidade de Santos. Resultados: Entre os 24 casais selecionados, 22 apresentaram o mesmo subtipo viral e altas porcentagens de homologia (região NS5b) entre 93,0% e 99,4%. Os subtipos HCV apresentados foram dois (9,1%) casais infectados por 1a, nove (40,9%) com subtipo 1b, um (4,6%) com subtipo 2b e dez (45,5%) dos casais pelo subtipo HCV 3a. Os dois casais discordantes apresentaram índices de 70,1% e 82,2% e foram infectados pelos subtipos 2b e 1b, e 1b e 1a respectivamente. A média de tempo de convivência foi de 22,4 anos, variando de 2 a 45 anos e a renda per capta anual foi em média US$2,270/ano. Com base nos questionários e entrevistas os fatores de risco apresentados pelos casais foram: 9 (37,5%) transfusão de sangue, 17 (70,8%) U.D. endovenosa e 15 (62,5%) U.D. inalatória, 4 (16,7%) acupuntura e 5 (20,8%) tatuagem. O compartilhar de utensílios de higiene pessoal relatado pelos casais apresentou altos índices e 6 (25,0%) dos casais assumiram o uso comum de escova de dente, 16 (66,7%) lâmina de barbear, 21 (87,5%) cortador de unhas e 14 (58,3%) alicate de manicure. Os dois casais discordantes relataram fatores de risco como transfusão de sangue e U.D. Conclusão: A alta similaridade encontrada entre as cadeias genômicas do VHC pode dar suporte a hipótese de transmissão do VHC entre esses casais. O uso compartilhado de utensílios de higiene pessoal e o tempo de convivência tornam difícil a interpretação dos dados. O uso compartilhado de utensílios de higiene pessoal pode dificultar a interpretação dos dados em relação à transmissão sexual do VHC. A hipótese do sentido mais provável de transmissão do VHC, de homem para mulher, foi reforçada neste trabalho. / ABSTRACT Cavalheiro, NP. Hepatitis C: transmission between couples. São Paulo, 2004. 111p. Thesis (Doctoral) - Faculdade de Medicina, Universidade de São Paulo. Introduction: The occurrence and the efficiency of HCV sexual transmission in the absence of other risk factors are still very controversial. I investigated and analyzed 24 couples, both infected with HCV, of whom 22 shared the same viral subtype. A phylogenetic analysis of NS5b region showed high sequence homology among the infected couples. Objective: Analysis of the Hepatitis C transmission between heterosexuals couples. Methods: The study recruited 45 couples, 24 were included, with anti-HCV positive and clinical diagnosis of active chronic hepatitis. HCV infection was diagnosed by positivity of serum samples for anti HCV (third-version enzyme immunoassay) and by circulating HCV-RNA detected by Polymerase Chain Reaction (PCR). All blood samples were collected between 1999 and 2002. Sequencing of the 5’NC region was performed utilizing the research available TRUGENE HCV 5’NC Test (Bayer Health Care Diagnostics, Tarrytown, NY, USA). Sequencing of the NS5B region was performed by RT-PCR amplification with Titan One Tube RT-PCR Kits (Roche Molecular, Mannheim, Germany) and CLIP sequencing using a prototype NS5B genotyping assay (Bayer Health Care Diagnostics, Tarrytown, NY, USA). Sequence analysis was completed using the Open Gene DNA Sequencing System, Gene Objects software package (Version 3.1), and Gene Librarian module (Bayer Health Care Diagnostics, Tarrytown, NY, USA). Multiple sequence alignments of the NS5B region were performed with Clustal W (Clustal W Multiple Sequence Alignment Program, v1.7, June 1997), and phylogenetic trees were generated using the Neighbor Joining Method. A standardized questionnaire and interview was used to collect data concerning risk factors and sexual behaviors. Follow up of all subjects was conducted at the hepatitis clinic of the Clinical Hospital of the University of Sao Paulo and at the Hospital Guilherme Alvaro in the city of Santos, in the state of Sao Paulo, Brazil. Results: Among the 24 couples, 22 had matching viral subtypes with homology scores (NS5b) ranging from 93.0% to 99.4%. Of the 22 couples with matching subtype, two (9.1%) where infected with subtype 1a, nine (40.9%) with subtype 1b, one (4.6%) with subtype 2b and ten (45.5%) with subtype 3a. The two couples that did not show matching viral subtypes had scores of 70.1% and 82.2%, and were infected with subtypes 2b and 1b, and 1b and 1a, respectively. The average of duration of marriage was 22.4 years (range 2-45 years) and the per capita income was an average of US$2,270/year. Based on the questionnaire and interviews, cause of infection of the 24 couples could be attributed to: blood transfusions 9 (37.5%), drug use, I.V. 17(70.8%) and inhalation 15 (62.5%), acupuncture 4 (16.7%) and tattooing 5 (20.8%). Shared hygienic utensils showed a much higher correlation of possible route of transmission, and are better explained by the sequence homology data than by the other associated risk factors. A total of 6 (25.0%) couples shared tooth brushes, 16 (66.7%) shared shaving blades, 21 (87.5%) shared nail clippers and 14 (58.3%) shared manicure cutters. The two couples that had different subtypes, both of them related transfusion blood and I.V. drug use. Conclusions: The high similarity found among the genome chains of HCV supports the hypothesis of transmission between these couples. The shared use of personal hygiene utensils and the amount of time spent living together made it difficult to interpret the data. Also, the shared use of personal hygiene utensils can make it difficult to interpret the data in relation to the sexual transmission of HCV. The hypothesis in relation to the direction of the HCV transmission, from man to woman, was reinforced in this work.
162

CNC-C2: um controlador aderente às normas ISO 14649 E IEC 61499 / CNC-C2: um controlador aderente às normas ISO 14649 e IEC 61499

Harbs, Eduardo 09 October 2012 (has links)
Made available in DSpace on 2016-12-12T17:38:31Z (GMT). No. of bitstreams: 1 Eduardo Harbs.pdf: 12792734 bytes, checksum: b505810b68894ae2924a805e7f89d032 (MD5) Previous issue date: 2012-10-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The industry has found difficulties towards CNC machines flexibility, due to the CNC programming current standard, the ISO 6983 or G/M code. The ISO 14649 or STEP-NC was developed to replace the current standard. It is a new unified data transfer model between CAD/CAM and CNC systems. To satisfy the new automation and control systems requirements, the IEC 61499 standard was developed, aiming the use of software objects, called function blocks (FBs). In this work, the standards STEP-NC and IEC 61499 were integrated to build a new generation of CNC, where STEP-NC supplies the complete data model without functionality, and the FBs provide the functionalities to the data model for the machine tool command. In this context, a controller for a CNC machine prototype, compliant to STEP-NC and IEC 61499 standards was developed. The prototype consists of a 2,5D milling machine, driven by a group of three servomotors drivers with integrated PLCs. A set of software was developed for compiling STEP-NC files and the automatic generation of IEC 61499 models, viewing, editing and executing FBs and FB networks, and further a library with IEC 61499 models. Test on software and prototype was performed machining an example workpiece, achieving the proposed goal and providing the individual characteristics of the standards in the controller, such as: interoperability, portability, use of features, configurability, distribution and adaptability. / A indústria tem enfrentado dificuldades quanto à flexibilidade das máquinas CNC, devido à norma utilizada atualmente para a programação CNC, a ISO 6983 ou código G/M. Com objetivo de substituição desta norma, desenvolveu-se a ISO 14649 ou STEP-NC, que é um novo modelo de transferência de dados unificado entre sistemas CAD/CAM e CNC. Para atender os novos requisitos de automação e controle de sistemas, desenvolveu-se a norma IEC 61499, visando o uso de objetos de software, os function blocks (FBs). Neste trabalho integraram-se as normas STEP-NC e IEC 61499 para a construção de uma nova geração de CNCs, onde STEP-NC fornece o modelo de dados completo, porém sem funcionalidade, e os FBs fornecem as funcionalidades ao modelo de dados para o controle da máquina-ferramenta. Para tal, foi desenvolvido um controlador para uma máquina CNC protótipo aderente às normas STEP-NC e IEC 61499. Este protótipo é constituído de uma fresadora 2,5D, acionada por um conjunto de três servoacionamentos com CLPs integrados. Um conjunto de software foi desenvolvido para compilação do arquivo STEP-NC e geração automática de modelos IEC 61499, visualização, edição e execução de FBs e rede de FBs além de uma biblioteca de modelos IEC 61499. Teste do software e do protótipo foi realizado com a usinagem de uma peça exemplo, alcançando o objetivo proposto e provendo as características individuais das normas no controlador, como: interoperabilidade, portabilidade, uso de features, configurabilidade, distribuição e adaptabilidade.
163

Ingénierie de la chaîne numérique d'industrialisation : proposition d'un modèle d'interopérabilité pour la conception-fabrication intégrées / Toward a bidirectional and continuous digital chain from CAD to CNC machine : aeronautical industry application

Danjou, Christophe 03 December 2015 (has links)
Ce travail s'intéresse à la gestion d'information techniques et connaissances métiers issues de la production pour assurer l'interopérabilité et la continuité de la chaîne numérique. Dans un contexte d'entreprise étendue et de développement des technologies de l’information pour l'usine du futur, l'industrie aéronautique s'oriente vers une intégration flexible et agile des phases de conception et fabrication pour l'obtention de pièces bonnes du premier coup. C'est pour assurer la maîtrise des processus et la capitalisation des savoir-faire métier issus de la fabrication que ces travaux adressent la problématique suivante : comment élaborer un modèle d'interopérabilité de la chaîne numérique d'industrialisation, pour assurer une intégration agile de la conception et de la fabrication ? Pour ce faire, nous définissons deux propositions : OntoSTEP-NC pour permettre l'extraction et la structuration des données issues de la fabrication et Closed-Loop Manufacturing pour permettre l'intégration et la réutilisation des connaissances métiers capitalisées au niveau de l'industrialisation. Les apports de ces propositions se retrouvent dans la définition d'un cadre d'interopérabilité pour l'usine du futur mais également dans les enjeux tels que la définition de bonnes pratiques pour l'entreprise étendue en vue d'une harmonisation des processus de fabrication. Ces travaux ont été validés au travers d'un démonstrateur sur un cas d'étude industriel comportant plusieurs scénarii. / This work focuses on the knowledge and the data management extracted from the manufacturing to ensure the interoperability in the digital chain. According to the extended enterprise and the factory of the future context, the aeronautics manufacturers tend to a design and manufacturing integrated platform in order to get a right part the first time.This work focus on manufacturing process control and capitalization of know-how from the manufacturing aiming at answering the following issue : How to enable interoperability for the digital production process in order to ensure an integrated and agile design and manufacturing ? This issue is addressed with two proposals : OntoSTEP-NC which focuses on how to model and structure the manufacturing knowledge from the CNC machine and Closed-Loop Manufacturing which focuses on how to re-use and integrate the information feedback from manufacturing to process engineering. Both combined those two proposals address the main issue of this work defining an interoperability framework for the factory of the future and address trends like the definition of guidelines for manufacturing in extended enterprise context. This work has been validated through a demonstrator and an industrial case study with various scenarios.
164

Vliv interferon regulujícího faktoru 3 na imunitní odpověď proti viru vakcínie v atopickém organismu / Effects of the Interferon regulatory factor 3 on immune responses to vaccinia virus in the atopic organism

Pilná, Hana January 2019 (has links)
Vaccinia virus (VACV) is an enveloped DNA virus, member of the Orthopoxviridae genus. VACV genome size is about 200 kbp. This huge genome capacity allows VACV to encode a set of factors that are non-essential for virus replication and spread in vitro. While these factors are needed for interfering with host immune responses, VACV remains strongly immunogenic. Cell-mediated and humoral immune responses in atopic disorders are deregulated to a certain extent, leading to complications in case of infection or vaccination with vaccines based on replicating viruses, such as eczema vaccinatum caused by VACV. VACV effects on immune responses consist among others in the inhibition of expression of type I interferon (IFN) at various levels - for example in a specific inhibition of phosphorylation of the interferon regulatory factor-3 (IRF-3) via inhibition of the activity of TANK-binding kinase 1 (TBK 1) that normally phosphorylates IRF-3. Phosphorylation allows IRF-3 to translocate into the nucleus where it initiates transcription of IFNβ followed by induction of expression of IFN and interferon stimulated genes. Expression of these genes is shut down when IRF-3 activity is inhibited. To overcome this block, a recombinant VACV expressing murine IRF-3 under VACV p7.5 promotor (WR-IRF3) was generated....
165

A psychometric study of engineering and architectural drawings, with emphasis on the selection of pupils and students for technical education

Pal, A. K. January 1953 (has links)
An educational psychology thesis analysing technical and artistic abilities of pupils selected for technical education. Attempting to bridge the gap between the designer and the psychologist, the author makes a psychometric study of architectural and engineering drawing. Draftsmanship calls for practical intelligence. The draftsman needs, above all, the ability to think in-terms of space. He must be able to think in solid and to transfer an object from three to two dimensions and vice versa. Artistic ability does not play an important part in draftsmanship at the early stage of training.
166

An Image-Space Algorithm for Hardware-Based Rendering of Constructive Solid Geometry

Stewart, Nigel Timothy, nigels@nigels.com January 2008 (has links)
A new approach to image-space hardware-based rendering of Constructive Solid Geometry (CSG) models is presented. The work is motivated by the evolving functionality and performance of computer graphics hardware. This work is also motivated by a specific industrial application --- interactive verification of five axis grinding machine tool programs. The goal is to minimise the amount of time required to render each frame in an animation or interactive application involving boolean combinations of three dimensional shapes. The Sequenced Convex Subtraction (SCS) algorithm utilises sequenced subtraction of convex objects for the purpose of interactive CSG rendering. Concave shapes must be decomposed into convex shapes for the purpose of rendering. The length of Permutation Embedding Sequences (PESs) used as subtraction sequences are shown to have a quadratic lower bound. In many situations shorter sequences can be used, in the best case linear. Approaches to s ubtraction sequence encoding are presented including the use of object-space overlap information. The implementation of the algorithm is experimentally shown to perform better on modern commodity graphics hardware than previously reported methods. This work also examines performance aspects of the SCS algorithm itself. Overall performance depends on hardware characteristics, the number and spatial arrangement of primitives, and the structure and boolean operators of the CSG tree.
167

Optimisation de la programmation des MOCN - Application aux machines à structure parallèle

Rauch, Matthieu 10 December 2007 (has links) (PDF)
Les travaux de recherche présentés visent à définir des voies d'optimisation concernant la programmation des MOCN liées au développement des machines à structure parallèle. Nous avons identifié quatre axes de recherche permettant d'adapter la programmation de la machine à l'application visée. Le premier axe traite de la préparation de la fabrication, en particulier le choix de la stratégie d'usinage, en évaluant le potentiel de nouvelles trajectoires (tréflage et usinage trochoïdal) et en définissant des fenêtres de performance pour les principales stratégies d'usinage en fonction des aptitudes de la machine employée. Le deuxième axe se focalise sur le formage incrémental, procédé émergent. Nous montrons que le recours à une programmation adaptée améliore la mise en oeuvre de ce procédé et que les voies d'optimisation sont fonction des capacités de la MOCN choisie. Au cours du troisième axe, nous proposons une nouvelle approche de programmation avancée des parcours d'outil, la méthode ICAM (Intelligent Computer Aided Manufacturing). Elle permet d'optimiser la programmation implémentée en s'appuyant sur une évaluation par le DCN de données process en cours de fabrication. Le quatrième axe porte enfin sur les évolutions à moyen terme de la programmation en s'intéressant d'un côté aux mutations de l'environnement des MOCN générées par le développement de l'e-manufacturing et d'un autre côté à la mise en place d'un nouveau standard de programmation des machine outils, le format Step_NC. Ce dernier constitue un cadre idéal aux optimisations proposées pour les autres axes de recherche, en plus de conduire à de nouvelles avancées en programmation des MOCN.
168

Development and simulation of hard real-time switched-ethernet avionics data network

Chen, Tao 08 1900 (has links)
The computer and microelectronics technologies are developing very quickly nowadays. In the mean time, the modern integrated avionics systems are burgeoning unceasingly. The modern integrated modular architecture more and more requires the low-latency and reliable communication databus with the high bandwidth. The traditional avionics databus technology, such as ARINC429, can not provide enough high speed and size for data communication, and it is a problem to achieve transmission mission successfully between the advanced avionic devices with the sufficient bandwidth. AFDX(Avionics Full Duplex Switched Ethernet) is a good solution for this problem, which is the high-speed full duplex switched avionic databus, on the basis of the Ethernet technology. AFDX can not only avoid Ethernet conflicts and collisions, but also increase transmission rate with a lower weigh of the databus. AFDX is now adopted by A380,B787 aircraft successfully. The avionics data must be delivered punctualy and reliablely, so it is very essential to validate the real-time performance of AFDX during the design process. The simulation is a good method to acquire the network performance, but it only happends in some given set of scenarios, and it is impossible to consider every case. So a sophisticatd network performance method for the worst-case scenario with the pessimistic upper bound requires to be deduced. The avionic design engineers have launched many researches in the AFDX simulation and methods study. That is the goal that this thesis is aimming for. The development of this project can been planned in the following two steps. In the first step, a communication platform plans to be implemented to simulate the AFDX network in two versions – the RTAI realtime framework and Linux user space framework. Ultimately, these frameworks need to be integrated into net-ASS, which is an integrated simulation and assessment platform in the cranfield’s lab.The second step deduces an effective method to evaluate network performance, including three bounds(delay,backlog and output flow), based on the NC. It is called Network Calculus. It is an internet theory keeping the network system in determistic way. It is also used in communication queue management. This mathematics method is planed to be verified with simulation results from the AFDX simuation communication platform, in order to assure its validity and applicability. All in all, the project aims to assess the performance of different network topologies in different avionic architectures, through the simulation and the mathematical assessment. The technologies used in this thesis benefit to find problems and faults in the beginning stage of the avionics architecture design in the industrial project, especially, in terms of guarantee the lossless service in avionics databus.
169

Communicating Corporate Identity Through Form Attributes And Evaluating Visual Analogy Of Digital Cameras.

Cekceoglu, Engin 01 November 2006 (has links) (PDF)
The basic notion of this study is related with visual attributes of products which reflect the identity of the company as well as form and design consistency which is a factor forming corporate identity. The sub-notions of the topic are elaborated in the literature review. The efforts which aimed at finding out the distinguishing characteristics of products focused on certain sample products. Digital camera is selected for the field study. The objective of the study is to put evidence that firms can be distinguished from each other with the help of visual attributes of their products and to determine which factors are effective throughout this process.
170

The Contribution Of User-centered Design To Consumer Packages

Kesercioglu, Burcin 01 October 2005 (has links) (PDF)
End-users often complain about usability and safety problems in consumer packages. This study shows that these issues are an obstacle to the achievement of user satisfaction and to gain a competitive advantage in the market. To this end, a case study on food and beverage packages was done in order to identify and analyze these usability and safety problems based on the lifetime phases of packages in which end-users are involved. The study revealed that safety, clarity, legibility, visibility, storability, openability, re-closability, usefulness, and pleasantness are key areas where problems are widespread and should be considered by package developers and designers. The study also indicated that the problems occurred during use result from insufficiencies in current package design processes. These insufficiencies occur basically in the specification of the context of package use, identification of usability requirements, and the active involvement of the actual users in the package design processes. This study also highlights the need for a user-centered approach to package design in order to overcome the insufficiencies in current package design processes in a structured way and thus to achieve usable and safe packages. In addition, based on the literature and case study findings, checklists for user-centered package design process activities and for the design and evaluation of the packages are included. Moreover, a set of methods to be used during user-centered package design process is recommended.

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