829 resultados para computer-aided engineering tool


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OBJETIVO: Avaliar a reprodutibilidade do volume do braço e coxa fetais aferido pela ultrassonografia tridimensional utilizando o método eXtended Imaging Virtual Organ Computer-aided AnaLysis (XI VOCAL). MATERIAIS E MÉTODOS: Realizou-se estudo de reprodutibilidade com 43 fetos normais entre 20 e 37 semanas. Para o cálculo do volume do braço e coxa fetais utilizou-se o método XI VOCAL com delimitação de 10 planos consecutivos. Para o cálculo da variabilidade interobservador, um examinador realizou uma medida do volume do braço e coxa dos 43 fetos, enquanto um segundo examinador, sem o conhecimento prévio dos resultados do primeiro examinador, realizou uma segunda medida dos mesmos volumes. Utilizaram-se, para os cálculos estatísticos, o coeficiente de correlação intraclasse (ricc), gráficos de Bland-Altman e teste t-Student pareado (p). RESULTADOS: Observou-se alta reprodutibilidade interobservador. Para o volume do braço, obtiveram-se ricc = 0,996 (intervalo de confiança [IC] 95%: 0,992; 0,998) e média das diferenças = 0,13 ± 1,29% (95% limites de concordância: -2,54; +2,54%). Para o volume da coxa, obtiveram-se ricc = 0,997 (IC 95%: 0,995; 0,999) e média das diferenças = 0,24 ± 7,60% (95% limites de concordância: -7,6; +7,6%). CONCLUSÃO: O volume do braço e coxa fetais aferido pela ultrassonografia tridimensional utilizando o método XI VOCAL apresentou elevada reprodutibilidade interobservador.

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OBJETIVO: Avaliar a reprodutibilidade intra e interobservador do Doppler de amplitude tridimensional (3D power Doppler) na avaliação do fluxo sanguíneo cerebral do território da artéria cerebral média. MATERIAIS E MÉTODOS: Foi realizado estudo transversal com 20 gestantes normais entre 26 e 34 semanas. O território da artéria cerebral média mais próximo ao transdutor foi selecionado e o volume foi calculado utilizando-se o método Virtual Organ Computer-aided AnaLysis. Posteriormente, obtiveram-se os índices do 3D power Doppler: índice de vascularização (VI), índice de fluxo (FI) e índice de vascularização-fluxo (VFI). Utilizaram-se, para os cálculos, o coeficiente de correlação intraclasse (CCI) e gráficos de Bland-Altman. RESULTADOS: Foi observada boa concordância intra e interobservador, com CCI > 0,90 para todos os índices do 3D power Doppler: VI [CCI = 0,992 (IC 95%: 0,981-0,997)], FI [CCI = 0,999 (IC 95%: 0,998-0,999)], VFI [CCI = 0,995 (IC 95%: 0,987-0,998)]. Reprodutibilidade interobservador: VI [CCI = 0,988 (IC 95%: 0,970-0,995)], FI [CCI = 0,999 (IC 95%: 0,997-1,000)], VFI [CCI = 0,994 (IC 95%: 0,994-0,998)]. CONCLUSÃO: O 3D power Doppler mostrou-se um método prático, fácil e com boa reprodutibilidade intra e interobservador, com o IF evidenciando a melhor concordância intra e interobservador

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A mamografia representa o melhor método de detecção precoce do câncer de mama, porém cerca de 10% a 30% das lesões mamárias são perdidas no rastreamento, devido a limitações próprias dos observadores humanos. A detecção auxiliada por computador (computer-aided detection - CAD) é uma tecnologia relativamente nova que tem sido implementada em alguns serviços de mamografia, com o intuito de prover uma dupla leitura. Estudos clínicos têm demonstrado que o CAD aumenta a sensibilidade de detecção do câncer da mama, por radiologistas, em até 21%. Um sistema CAD é útil em situações em que exista alta variabilidade interobservador, falta de observadores treinados, ou na impossibilidade de se realizar a dupla leitura com dois ou mais radiologistas. O objetivo desta revisão está baseado na necessidade de atualizar a comunidade médica acerca desta ferramenta, como um método auxiliar, quantitativo, não operador-dependente, e que visa a melhorar a qualidade do diagnóstico do câncer de mama.

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Background: The DNA repair protein O6-Methylguanine-DNA methyltransferase (MGMT) confers resistance to alkylating agents. Several methods have been applied to its analysis, with methylation-specific polymerase chain reaction (MSP) the most commonly used for promoter methylation study, while immunohistochemistry (IHC) has become the most frequently used for the detection of MGMT protein expression. Agreement on the best and most reliable technique for evaluating MGMT status remains unsettled. The aim of this study was to perform a systematic review and meta-analysis of the correlation between IHC and MSP. Methods A computer-aided search of MEDLINE (1950-October 2009), EBSCO (1966-October 2009) and EMBASE (1974-October 2009) was performed for relevant publications. Studies meeting inclusion criteria were those comparing MGMT protein expression by IHC with MGMT promoter methylation by MSP in the same cohort of patients. Methodological quality was assessed by using the QUADAS and STARD instruments. Previously published guidelines were followed for meta-analysis performance. Results Of 254 studies identified as eligible for full-text review, 52 (20.5%) met the inclusion criteria. The review showed that results of MGMT protein expression by IHC are not in close agreement with those obtained with MSP. Moreover, type of tumour (primary brain tumour vs others) was an independent covariate of accuracy estimates in the meta-regression analysis beyond the cut-off value. Conclusions Protein expression assessed by IHC alone fails to reflect the promoter methylation status of MGMT. Thus, in attempts at clinical diagnosis the two methods seem to select different groups of patients and should not be used interchangeably.

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Medicinal chemistry is multi, trans and inter disciplinary on its essence. It has a great deal of challenging Brazilian chemists in the next decade. The pharmacy school is essentially attached and has an important role in the development on the field that is still in domain of big pharmaceutical industries. This work shows the challenges to face and directions to jointly follow for a myriad of researchers throughout the country. The unnamed science has to work out through specific objectives in order to diminish the problems associated with human being health. A brief history is presented where the main goal is to devise chemistry, as a natural science, and many other interfaced disciplines.

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Parametriset NURBS-käyrät ja -pinnat ovat yleisiä työkaluja graafisessa mallinnuksessa, tietokoneavusteisessa suunnittelussa ja muissa sovelluksissa. NURBS-mallinnus on pääosin melko intuitiivista, mutta siinä on joitakin vaikeammin ymmärrettäviä osia. Ihminen oppii parhaiten tekemällä, minkä takia päätettiin tehdä interaktiivinen NURBS-opetussovelma, joka tutustuttaa käyttäjän NURBSien toimintaan. Sovelma toimii www-selaimessa Java-liitännäisen avulla ja hyödyntää Java OpenGL -grafiikkarajapintaa kolmiulotteisen grafiikan piirtämiseen. Sovelma on helppokäyttöinen ja opastaa käyttäjää NURBS-mallinnuksen eri osa-alueissa.

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This thesis introduces a real-time simulation environment based on the multibody simulation approach. The environment consists of components that are used in conventional product development, including computer aided drawing, visualization, dynamic simulation and finite element software architecture, data transfer and haptics. These components are combined to perform as a coupled system on one platform. The environment is used to simulate mobile and industrial machines at different stages of a product life time. Consequently, the demands of the simulated scenarios vary. In this thesis, a real-time simulation environment based on the multibody approach is used to study a reel mechanism of a paper machine and a gantry crane. These case systems are used to demonstrate the usability of the real-time simulation environment for fault detection purposes and in the context of a training simulator. In order to describe the dynamical performance of a mobile or industrial machine, the nonlinear equations of motion must be defined. In this thesis, the dynamical behaviour of machines is modelled using the multibody simulation approach. A multibody system may consist of rigid and flexible bodies which are joined using kinematic joint constraints while force components are used to describe the actuators. The strength of multibody dynamics relies upon its ability to describe nonlinearities arising from wearing of the components, friction, large rotations or contact forces in a systematic manner. For this reason, the interfaces between subsystems such as mechanics, hydraulics and control systems of the mechatronic machine can be defined and analyzed in a straightforward manner.

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The purpose of this thesis is to develop an environment or network that enables effective collaborative product structure management among stakeholders in each unit, throughout the entire product lifecycle and product data management. This thesis uses framework models as an approach to the problem. Framework model methods for development of collaborative product structure management are proposed in this study, there are three unique models depicted to support collaborative product structure management: organization model, process model and product model. In the organization model, the formation of product data management system (eDSTAT) key user network is specified. In the process model, development is based on the case company’s product development matrix. In the product model framework, product model management, product knowledge management and design knowledge management are defined as development tools and collaboration is based on web-based product structure management. Collaborative management is executed using all these approaches. A case study from an actual project at the case company is presented as an implementation; this is to verify the models’ applicability. A computer assisted design tool and the web-based product structure manager, have been used as tools of this collaboration with the support of the key user. The current PDM system, eDSTAT, is used as a piloting case for key user role. The result of this development is that the role of key user as a collaboration channel is defined and established. The key user is able to provide one on one support for the elevator projects. Also the management activities are improved through the application of process workflow by following criteria for each project milestone. The development shows effectiveness of product structure management in product lifecycle, improved production process by eliminating barriers (e.g. improvement of two-way communication) during design phase and production phase. The key user role is applicable on a global scale in the company.

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The genetic diversity of begomovirus isolates from tomato (Lycopersicon esculentum) fields in the Southeastern region of Brazil was analyzed by direct sequencing of PCR fragments amplified by using universal oligonucleotides for the begomovirus DNA-A, and subsequent computer-aided phylogenetic analysis. Samples of tomato plants and associated weeds showing typical symptoms of virus infection were collected at seven locations in the states of Minas Gerais, Espírito Santo and Rio de Janeiro. A total of 137 out of 369 samples were infected with a begomovirus based on PCR analysis. Phylogenetic analysis indicated a high degree of genetic diversity among begomoviruses infecting tomatoes in the sampled area. One species (Tomato chlorotic mottle virus, TCMV) occurs predominantly in Minas Gerais, whereas in Rio de Janeiro and Espírito Santo a distinct species, not yet fully characterized, predominates. Phylogenetic analysis further indicates the presence of an additional four possible new species. This high degree of genetic diversity suggests a recent transfer of indigenous begomovirus from wild hosts into tomatoes. The close phylogenetic relationship verified between begomovirus infecting tomato and associated weeds favors this hypothesis.

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This study presents an automatic, computer-aided analytical method called Comparison Structure Analysis (CSA), which can be applied to different dimensions of music. The aim of CSA is first and foremost practical: to produce dynamic and understandable representations of musical properties by evaluating the prevalence of a chosen musical data structure through a musical piece. Such a comparison structure may refer to a mathematical vector, a set, a matrix or another type of data structure and even a combination of data structures. CSA depends on an abstract systematic segmentation that allows for a statistical or mathematical survey of the data. To choose a comparison structure is to tune the apparatus to be sensitive to an exclusive set of musical properties. CSA settles somewhere between traditional music analysis and computer aided music information retrieval (MIR). Theoretically defined musical entities, such as pitch-class sets, set-classes and particular rhythm patterns are detected in compositions using pattern extraction and pattern comparison algorithms that are typical within the field of MIR. In principle, the idea of comparison structure analysis can be applied to any time-series type data and, in the music analytical context, to polyphonic as well as homophonic music. Tonal trends, set-class similarities, invertible counterpoints, voice-leading similarities, short-term modulations, rhythmic similarities and multiparametric changes in musical texture were studied. Since CSA allows for a highly accurate classification of compositions, its methods may be applicable to symbolic music information retrieval as well. The strength of CSA relies especially on the possibility to make comparisons between the observations concerning different musical parameters and to combine it with statistical and perhaps other music analytical methods. The results of CSA are dependent on the competence of the similarity measure. New similarity measures for tonal stability, rhythmic and set-class similarity measurements were proposed. The most advanced results were attained by employing the automated function generation – comparable with the so-called genetic programming – to search for an optimal model for set-class similarity measurements. However, the results of CSA seem to agree strongly, independent of the type of similarity function employed in the analysis.

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OBJETIVOS: avaliar a reprodutibilidade intra-observador e interobservador da medida do volume endometrial utilizando ultra-sonografia tridimensional (3D) e o programa VOCAL® (Virtual Organ Computer-aided AnaLysis). MÉTODOS: um bloco ultra-sonográfico 3D do endométrio foi obtido de cinco pacientes inférteis voluntárias que apresentavam diferentes volumes endometriais. Para cada bloco 3D, o volume endometrial foi calculado utilizando o modo manual em quatro diferentes passos de rotação (30º, 15º, 9º e 6º) por dois diferentes observadores. Dez medidas foram obtidas para cada rotação e por cada observador. Testamos a diferença entre as médias com o one-way ANOVA e o pós-teste de Tukey e a reprodutibilidade com os coeficientes de correlação intraclasse. RESULTADOS: as medidas realizadas com passo de rotação de 30º foram associadas a médias significativamente menores em 3 das 5 pacientes. Não houve diferença entre as médias obtidas pelos passos de rotação de 15º, 9º ou 6º. Em nenhuma das avaliações foi notada diferença entre as médias obtidas pelos dois observadores. Os coeficientes de correlação intraclasse foram significativamente menores com o passo de rotação de 30º (todos abaixo de 0,984) que com os outros passos de rotação (todos acima de 0,996). CONCLUSÕES: o uso de passos de rotação de 15º ou menos apresentou medidas reprodutíveis do volume endometrial: não houve diferença significativa entre as médias obtidas pelos dois observadores, associado ao alto coeficiente de correlação intraclasse (>0,996). É recomendável o uso do passo de rotação de 15º, pois demora menos para ser obtido em comparação com 6º e 9º.

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OBJETIVO: avaliar a evolução do volume do embrião (VE) entre a sétima e a décima semana de gestação por meio da ultra-sonografia tridimensional. MÉTODOS: realizou-se um estudo de corte transversal com 63 gestantes normais entre a sétima e a décima semana. Os exames ultra-sonográficos foram realizados por meio de um transdutor endocavitário volumétrico. Para o cálculo do VE, utilizou-se o método VOCAL (Virtual Organ Computer-aided Analysis) com ângulo de rotação de 12º, com delimitação de 15 planos seqüenciais. Para o VE foram calculadas médias, medianas, desvios padrão e valores máximo e mínimo em todas as idades gestacionais. Para se avaliar a correlação entre o VE e o comprimento cabeça-nádega (CCN) foi criado gráfico de dispersão, sendo o ajuste realizado pelo coeficiente de determinação (R²). Para se determinarem intervalos de referência do VE em função do CCN, utilizou-se a seguinte fórmula: percentil =VE+K versus dp, com K=1,96. RESULTADOS: o CCN variou de 9,0 a 39,7 mm, com média de 23,9 mm (±7,9 mm), enquanto o VE variou de 0,1 a 7,6 cm³, com média de 2,7 cm³ (±3,2 cm³). O VE foi altamente correlacionado com o CCN, sendo que o melhor ajuste foi obtido com regressão quadrática (VE=0,165 - 0,055 x CCN + 0,005 x CCN²; R²=0,853). O VE médio variou de 0,1 (-0,3 a 0,5 cm³) a 6,7 cm³ (3,8 a 9,7 cm³) no intervalo de 9 a 40 mm do CCN. Neste intervalo o VE aumentou 67 vezes, enquanto o CCN aumentou apenas 4,4 vezes. CONCLUSÕES: o VE é um parâmetro mais sensível que o CCN para avaliar o crescimento embrionário entre a sétima e a décima semana de gestação.

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In this paper a computer program to model and support product design is presented. The product is represented through a hierarchical structure that allows the user to navigate across the product’s components, and it aims at facilitating each step of the detail design process. A graphical interface was also developed, which shows visually to the user the contents of the product structure. Features are used as building blocks for the parts that compose the product, and object-oriented methodology was used as a means to implement the product structure. Finally, an expert system was also implemented, whose knowledge base rules help the user design a product that meets design and manufacturing requirements.

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Vaikka liiketoimintatiedon hallintaa sekä johdon päätöksentekoa on tutkittu laajasti, näiden kahden käsitteen yhteisvaikutuksesta on olemassa hyvin rajallinen määrä tutkimustietoa. Tulevaisuudessa aiheen tärkeys korostuu, sillä olemassa olevan datan määrä kasvaa jatkuvasti. Yritykset tarvitsevat jatkossa yhä enemmän kyvykkyyksiä sekä resursseja, jotta sekä strukturoitua että strukturoimatonta tietoa voidaan hyödyntää lähteestä riippumatta. Nykyiset Business Intelligence -ratkaisut mahdollistavat tehokkaan liiketoimintatiedon hallinnan osana johdon päätöksentekoa. Aiemman kirjallisuuden pohjalta, tutkimuksen empiirinen osuus tunnistaa liiketoimintatiedon hyödyntämiseen liittyviä tekijöitä, jotka joko tukevat tai rajoittavat johdon päätöksentekoprosessia. Tutkimuksen teoreettinen osuus johdattaa lukijan tutkimusaiheeseen kirjallisuuskatsauksen avulla. Keskeisimmät tutkimukseen liittyvät käsitteet, kuten Business Intelligence ja johdon päätöksenteko, esitetään relevantin kirjallisuuden avulla – tämän lisäksi myös dataan liittyvät käsitteet analysoidaan tarkasti. Tutkimuksen empiirinen osuus rakentuu tutkimusteorian pohjalta. Tutkimuksen empiirisessä osuudessa paneudutaan tutkimusteemoihin käytännön esimerkein: kolmen tapaustutkimuksen avulla tutkitaan sekä kuvataan toisistaan irrallisia tapauksia. Jokainen tapaus kuvataan sekä analysoidaan teoriaan perustuvien väitteiden avulla – nämä väitteet ovat perusedellytyksiä menestyksekkäälle liiketoimintatiedon hyödyntämiseen perustuvalle päätöksenteolle. Tapaustutkimusten avulla alkuperäistä tutkimusongelmaa voidaan analysoida tarkasti huomioiden jo olemassa oleva tutkimustieto. Analyysin tulosten avulla myös yksittäisiä rajoitteita sekä mahdollistavia tekijöitä voidaan analysoida. Tulokset osoittavat, että rajoitteilla on vahvasti negatiivinen vaikutus päätöksentekoprosessin onnistumiseen. Toisaalta yritysjohto on tietoinen liiketoimintatiedon hallintaan liittyvistä positiivisista seurauksista, vaikka kaikkia mahdollisuuksia ei olisikaan hyödynnetty. Tutkimuksen merkittävin tulos esittelee viitekehyksen, jonka puitteissa johdon päätöksentekoprosesseja voidaan arvioida sekä analysoida. Despite the fact that the literature on Business Intelligence and managerial decision-making is extensive, relatively little effort has been made to research the relationship between them. This particular field of study has become important since the amount of data in the world is growing every second. Companies require capabilities and resources in order to utilize structured data and unstructured data from internal and external data sources. However, the present Business Intelligence technologies enable managers to utilize data effectively in decision-making. Based on the prior literature, the empirical part of the thesis identifies the enablers and constraints in computer-aided managerial decision-making process. In this thesis, the theoretical part provides a preliminary understanding about the research area through a literature review. The key concepts such as Business Intelligence and managerial decision-making are explored by reviewing the relevant literature. Additionally, different data sources as well as data forms are analyzed in further detail. All key concepts are taken into account when the empirical part is carried out. The empirical part obtains an understanding of the real world situation when it comes to the themes that were covered in the theoretical part. Three selected case companies are analyzed through those statements, which are considered as critical prerequisites for successful computer-aided managerial decision-making. The case study analysis, which is a part of the empirical part, enables the researcher to examine the relationship between Business Intelligence and managerial decision-making. Based on the findings of the case study analysis, the researcher identifies the enablers and constraints through the case study interviews. The findings indicate that the constraints have a highly negative influence on the decision-making process. In addition, the managers are aware of the positive implications that Business Intelligence has for decision-making, but all possibilities are not yet utilized. As a main result of this study, a data-driven framework for managerial decision-making is introduced. This framework can be used when the managerial decision-making processes are evaluated and analyzed.

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Electrical keyboard instruments and computer-aided music-making generally base on the piano keyboard that was developed for a tuning system no longer used. Alternative keyboard layout offers at least easier playing, faster adopting, new ways to play and better ergonomics. This thesis explores the development of keyboard instruments and tunings, and different keyboard layouts. This work is preliminary research for an electrical keyboard instrument to be implemented later on.