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‣ Uso efetivo da matemática intervalar em supercomputadores vetoriais; Effective use of interval mathematics on vector supercomputers

Diverio, Tiaraju Asmuz
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Tese de Doutorado Formato: application/pdf
Português
Relevância na Pesquisa
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Este trabalho apresenta um estudo do uso da Matemática Intervalar na resolução de problemas em supercomputadores, através da biblioteca de rotinas intervalares denominada libavi.a (aritmética vetorial intervalar), proporcionando não só aumento de velocidade de processamento via vetorização, mas exatidão e controle de erros nos cálculos através do emprego da aritmética intervalar. Foram identificadas duas das barreiras que a resolução de problemas numéricos em computadores enfrenta. Estas barreiras se referem a qualidade do resultado e ao porte do problema a ser resolvido. Verificou-se a existência de uma grande lacuna entre o avanço tecnol6gico, incluindo o desenvolvimento de computadores cada vez mais rápidos, e poderosos e a qualidade com que os cálculos são feitos. Através dos supercomputadores (geralmente computadores vetoriais e/ou paralelos), os resultados são) obtidos com extrema rapidez, mas nem sempre se sabe quão confiáveis realmente são. Como a definição da aritmética da maquina ficava a cargo do fabricante, cada sistema tinha as suas próprias características e defeitos. Cálculos efetuados em diferentes maquinas raramente produziam resultados compatíveis. Então, em 1980, a IEEE adotou o padrão de aritmética binária de ponto-flutuante...

‣ Building roof contour extraction from LiDAR data

Dal Poz, Aluir P.; Galvanin, Edinéia A.S.
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Conferência ou Objeto de Conferência Formato: 88-92
Português
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This paper proposes a method for the automatic extraction of building roof contours from a LiDAR-derived digital surface model (DSM). The method is based on two steps. First, to detect aboveground objects (buildings, trees, etc.), the DSM is segmented through a recursive splitting technique followed by a region merging process. Vectorization and polygonization are used to obtain polyline representations of the detected aboveground objects. Second, building roof contours are identified from among the aboveground objects by optimizing a Markov-random-field-based energy function that embodies roof contour attributes and spatial constraints. Preliminary results have shown that the proposed methodology works properly.

‣ Reconhecimento semi-automatico e vetorização de regiões em imagens de sensoriamento remoto; Semi-automatic recognition and vectorization of regions in remote sensig images

Jefersson Alex dos Santos
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 27/02/2009 Português
Relevância na Pesquisa
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O uso de imagens de sensoriamento remoto (ISRs) como fonte de informação em aplicações voltadas para o agro-negócio e bastante comum. Nessas aplicações, saber como é a ocupação espacial é fundamental. Entretanto, reconhecer e diferenciar regiões de culturas agrícolas em ISRs ainda não é uma tarefa trivial. Embora existam métodos automáticos propostos para isso, os usuários preferem muitas vezes fazer o reconhecimento manualmente. Isso acontece porque tais métodos normalmente são feitos para resolver problemas específicos, ou quando são de propósito geral, não produzem resultados satisfatórios fazendo com que, invariavelmente, o usuário tenha que revisar os resultados manualmente. A pesquisa realizada objetivou a especificação e implementação parcial de um sistema para o reconhecimento semi-automático e vetorização de regiões em imagens de sensoriamento remoto. Para isso, foi usada uma estratégia interativa, chamada realimentação de relevância, que se baseia no fato de o sistema de classificação poder aprender quais são as regiões de interesse utilizando indicações de relevância feitas pelo usuário do sistema ao longo de iterações. A idéia é utilizar descritores de imagens para codificar informações espectrais e de textura de partições das imagens e utilizar realimentação de relevância com Programação Genética (PG) para combinar as características dos descritores. PG é uma técnica de aprendizado de máquina baseada na teoria da evolução. As principais contribuições deste trabalho são: estudo comparativo de técnicas de vetorização de imagens; adaptação do modelo de recuperação de imagens por conteúdo proposto recentemente para realização de realimentação de relevância usando regiões de imagem; adaptação do modelo de realimentação de relevância para o reconhecimento de regiões em ISRs; implementação parcial de um sistema de reconhecimento semi-automático e vetorização de regiões em ISRs; proposta de metodologia de validação do sistema desenvolvido; The use of remote sensing images as a source of information in agrobusiness applications is very common. In these applications...

‣ Gold nanoparticle-DNA conjugates for oligonucleotide vectorization towards gene silencing

Almeida, Carina Marisa dos Santos
Fonte: Faculdade de Ciências e Tecnologia Publicador: Faculdade de Ciências e Tecnologia
Tipo: Dissertação de Mestrado
Publicado em //2011 Português
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Dissertação para obtenção do Grau de Mestre em Genética Molecular e Biomedicina; The main objective of the work presented in this thesis was to develop a gene silencing system by taking advantage of the nanovectorization capability and optical properties of gold nanoparticles. The idea is based on the construction of a DNA structure containing a therapeutic oligonucleotide with the ability to form Hoogsteen hydrogen bonds with double-stranded DNA, producing a DNA triple helix, besides silencing the gene of interest. Hoogsteen bonds, more unstable than the conventional Watson-Crick bonds, permit the achievement of lower melting temperatures. This attribute, coupled with the ability to generate heat by laser irradiation of the gold nanoparticles used, will allow the release of the therapeutic oligonucleotide and subsequent gene silencing without significant increase in the medium’s temperature. Thus, the thesis comprises three major sections: structure design and formation, vectorization, and gene expression silencing; the tasks involved in each of these sections were conducted in parallel. The design of the obtained structure took into account the desired melting temperature, stability at physiological conditions of the sequence-forming nucleotides...

‣ Multidirectional Scanning Model, MUSCLE, to Vectorize Raster Images with Straight Lines

Karas, Ismail Rakip; Bayram, Bulent; Batuk, Fatmagul; Akay, Abdullah Emin; Baz, Ibrahim
Fonte: Molecular Diversity Preservation International (MDPI) Publicador: Molecular Diversity Preservation International (MDPI)
Tipo: Artigo de Revista Científica
Publicado em 15/04/2008 Português
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This paper presents a new model, MUSCLE (Multidirectional Scanning for Line Extraction), for automatic vectorization of raster images with straight lines. The algorithm of the model implements the line thinning and the simple neighborhood methods to perform vectorization. The model allows users to define specified criteria which are crucial for acquiring the vectorization process. In this model, various raster images can be vectorized such as township plans, maps, architectural drawings, and machine plans. The algorithm of the model was developed by implementing an appropriate computer programming and tested on a basic application. Results, verified by using two well known vectorization programs (WinTopo and Scan2CAD), indicated that the model can successfully vectorize the specified raster data quickly and accurately.

‣ Vetorização termoinduzida de nanopartículas magnéticas biocompatíveis: uma aplicação no recobrimento de Stents nus por via líquida; Thermally induced vectorization of Biocompatible Magnetic Nanoparticles: an application to cover Bare Metal Stents by Dip Coating

RODRIGUES, Harley Fernandes
Fonte: Universidade Federal de Goiás; BR; UFG; Mestrado em Física; Ciências Exatas e da Terra Publicador: Universidade Federal de Goiás; BR; UFG; Mestrado em Física; Ciências Exatas e da Terra
Tipo: Dissertação Formato: application/pdf
Português
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In this work we developed a Dip Coating method that could control the temperature gradient between a substrate and the material that one wants to adsorb at its surface. In particular, the adsorption of biocompatible magnetic nanoparticles at the surface of bare metal Stents, under different experimental conditions, was investigated. The magnetic nanoparticles consisted of magnetite coated with tripoliphosphate (mean diameter 7.68 nm and standard deviation 1.88 nm) dispersed in water at physiological conditions, while the Stent was a CoCr based-one (Cronus stent from Scitech with 16 mm length). Nine series of experiments were performed where it was controlled parameters as: time of adsorption, stent temperature and magnetic fluid temperature. The stents coated with nanoparticles were magnetically characterized using a vibrating sample magnetometer (VSM), which allowed us to determine the number of nanoparticles at the stent surface. The increase of the magnetic moment of the stent with the increase of the adsorption time was theoretically modeled, with an excellent experimental agreement, as a transient diffusion process of nanoparticles at the interface stent-magnetic fluid, which clearly indicates an important diffusive contribution. Strong evidences of thermal diffusion (Soret effect)...

‣ Vectorization using reversible data dependences

Tang, Peiyi; Gao, Nianshu
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Working/Technical Paper Formato: 216645 bytes; 356 bytes; application/pdf; application/octet-stream
Português
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Data dependences between statements have long been used for detecting parallelism and converting sequential programs into parallel forms. However, some data dependences can be reversed and the transformed program still produces the same results. In this paper, we revisit vectorization and propose a new vectorization algorithm using reversible data dependences. The new algorithm can generate more or thicker vector statements than traditional algorithm. The techniques presented in this paper can be incorporated in all the existing vectorizing compilers for supercomputers.; no

‣ Detection and vectorization of roads from lidar data

Clode, S.; Rottensteiner, F.; Kootsookos, P.; Zelniker, Emanuel Emil
Fonte: American Society for Photogrammetry and Remote Sensing Publicador: American Society for Photogrammetry and Remote Sensing
Tipo: Artigo de Revista Científica
Publicado em //2007 Português
Relevância na Pesquisa
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A method for the automatic detection and vectorization of roads from lidar data is presented. To extract roads from a lidar point cloud, a hierarchical classification technique is used to classify the lidar points progressively into road and non-road points. During the classification process, both intensity and height values are initially used. Due to the homogeneous and consistent nature of roads, a local point density is introduced to finalize the classification. The resultant binary classification is then vectorized by convolving a complex-valued disk named the Phase Coded Disk (PCD) with the image to provide three separate pieces of information about the road. The centerline and width of the road are obtained from the resultant magnitude image while the direction is determined from the corresponding phase image, thus completing the vectorized road model. All algorithms used are described and applied to two urban test sites. Completeness values of 0.88 and 0.79 and correctness values of 0.67 and 0.80 were achieved for the classification phase of the process. The vectorization of the classified results yielded RMS values of 1.56 m and 1.66 m, completeness values of 0.84 and 0.81 and correctness values of 0.75 and 0.80 for two different data sets.; Simon Clode...

‣ Computação paralela na classificação de proteínas sobre a plataforma Cellbe

Schuenemann, Hermann Pimentel
Fonte: Universidade de Lisboa Publicador: Universidade de Lisboa
Tipo: Dissertação de Mestrado
Publicado em //2010 Português
Relevância na Pesquisa
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Tese de mestrado, Informática, Universidade de Lisboa, Faculdade de Ciências, 2010; Um dos problemas maiores da bioinformática é a previsão de função de uma proteína. A tecnologia existente já permite obter milhões e milhões de sequências a custo muito reduzido, mas a compreensão de sua função dentro dos vários organismos é ainda um grande mistério para a larga maioria de sequências proteicas existentes. A criação de software eficiente que permita analisar bases de dados de proteínas em busca de metadados é também um desafio para os biólogos e uma área de estudo recente para os cientistas da computação, por representar uma alternativa de baixo custo aos métodos de teste em laboratório. Uma metodologia que se propõe analisar estas bases de dados e anotar as proteínas são os Peptide Programs (PepProg), uma metodologia de aprendizagem automática (machine learning) para classificação funcional de sequências biológicas. Esta dissertação de mestrado se propôs a estudar meios de optimizar o desempenho da implementação existente do método PepProg através da construção de uma implementação alternativa que explore a arquitectura do processador CellBE, presente nas consolas Playstation 3 disponibilizadas pelo Departamento de Informática da Universidade de Lisboa. Para explorar os recursos do CellBE...

‣ Compilation techniques for short-vector instructions

Larsen, Samuel (Samuel Barton), 1975-
Fonte: Massachusetts Institute of Technology Publicador: Massachusetts Institute of Technology
Tipo: Tese de Doutorado Formato: 133 p.
Português
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Multimedia extensions are nearly ubiquitous in today's general-purpose processors. These extensions consist primarily of a set of short-vector instructions that apply the same opcode to a vector of operands. This design introduces a data-parallel component to processors that exploit instruction-level parallelism, and presents an opportunity for increased performance. In fact, ignoring a processor's vector opcodes can leave a significant portion of the available resources unused. In order for software developers to find short-vector instructions generally useful, the compiler must target these extensions with complete transparency and consistent performance. This thesis develops compiler techniques to target short-vector instructions automatically and efficiently. One important aspect of compilation is the effective management of memory alignment. As with scalar loads and stores, vector references are typically more efficient when accessing aligned regions. In many cases, the compiler can glean no alignment information and must emit conservative code sequences. In response, I introduce a range of compiler techniques for detecting and enforcing aligned references. In my benchmark suite, the most practical method ensures alignment for roughly 75% of dynamic memory references.; (cont.) This thesis also introduces selective vectorization...

‣ Attenuation of Replication-Competent Adenovirus Serotype 26 Vaccines by Vectorization

Maxfield, Lori F.; Abbink, Peter; Stephenson, Kathryn E.; Borducchi, Erica N.; Ng'ang'a, David; Kirilova, Marinela M.; Paulino, Noelix; Boyd, Michael; Shabram, Paul; Ruan, Qian; Patel, Mayank; Barouch, Dan H.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Português
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Replication-competent adenovirus (rcAd)-based vaccine vectors may theoretically provide immunological advantages over replication-incompetent Ad vectors, but they also raise additional potential clinical and regulatory issues. We produced replication-competent Ad serotype 26 (rcAd26) vectors by adding the E1 region back into a replication-incompetent Ad26 vector backbone with the E3 or E3/E4 regions deleted. We assessed the effect of vectorization on the replicative capacity of the rcAd26 vaccines. Attenuation occurred in a stepwise fashion, with E3 deletion, E4 deletion, and human immunodeficiency virus type 1 (HIV-1) envelope (Env) gene insertion all contributing to reduced replicative capacity compared to that with the wild-type Ad26 vector. The rcAd26 vector with E3 and E4 deleted and containing the Env transgene exhibited 2.7- to 4.4-log-lower replicative capacity than that of the wild-type Ad26 in vitro. This rcAd26 vector is currently being evaluated in a phase 1 clinical trial. Attenuation as a result of vectorization and transgene insertion has implications for the clinical development of replication-competent vaccine vectors.

‣ Attenuation of Replication-Competent Adenovirus Serotype 26 Vaccines by Vectorization

Maxfield, Lori F.; Abbink, Peter; Stephenson, Kathryn E.; Borducchi, Erica N.; Ng'ang'a, David; Kirilova, Marinela M.; Paulino, Noelix; Boyd, Michael; Shabram, Paul; Ruan, Qian; Patel, Mayank; Barouch, Dan H.
Fonte: American Society for Microbiology Publicador: American Society for Microbiology
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.441099%
Replication-competent adenovirus (rcAd)-based vaccine vectors may theoretically provide immunological advantages over replication-incompetent Ad vectors, but they also raise additional potential clinical and regulatory issues. We produced replication-competent Ad serotype 26 (rcAd26) vectors by adding the E1 region back into a replication-incompetent Ad26 vector backbone with the E3 or E3/E4 regions deleted. We assessed the effect of vectorization on the replicative capacity of the rcAd26 vaccines. Attenuation occurred in a stepwise fashion, with E3 deletion, E4 deletion, and human immunodeficiency virus type 1 (HIV-1) envelope (Env) gene insertion all contributing to reduced replicative capacity compared to that with the wild-type Ad26 vector. The rcAd26 vector with E3 and E4 deleted and containing the Env transgene exhibited 2.7- to 4.4-log-lower replicative capacity than that of the wild-type Ad26 in vitro. This rcAd26 vector is currently being evaluated in a phase 1 clinical trial. Attenuation as a result of vectorization and transgene insertion has implications for the clinical development of replication-competent vaccine vectors.

‣ On Vectorization of Deep Convolutional Neural Networks for Vision Tasks

Ren, Jimmy SJ.; Xu, Li
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/01/2015 Português
Relevância na Pesquisa
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We recently have witnessed many ground-breaking results in machine learning and computer vision, generated by using deep convolutional neural networks (CNN). While the success mainly stems from the large volume of training data and the deep network architectures, the vector processing hardware (e.g. GPU) undisputedly plays a vital role in modern CNN implementations to support massive computation. Though much attention was paid in the extent literature to understand the algorithmic side of deep CNN, little research was dedicated to the vectorization for scaling up CNNs. In this paper, we studied the vectorization process of key building blocks in deep CNNs, in order to better understand and facilitate parallel implementation. Key steps in training and testing deep CNNs are abstracted as matrix and vector operators, upon which parallelism can be easily achieved. We developed and compared six implementations with various degrees of vectorization with which we illustrated the impact of vectorization on the speed of model training and testing. Besides, a unified CNN framework for both high-level and low-level vision tasks is provided, along with a vectorized Matlab implementation with state-of-the-art speed performance.; Comment: To appear in the 29th AAAI Conference on Artificial Intelligence (AAAI-15). Austin...

‣ Semi-automatic vectorization of linear networks on rasterized cartographic maps

Miravet, Carlos; Coiras, Enrique; Santamaria, Javier
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 22/03/2005 Português
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A system for semi-automatic vectorization of linear networks (roads, rivers, etc.) on rasterized cartographic maps is presented. In this system, human intervention is limited to a graphic, interactive selection of the color attributes of the information to be obtained. Using this data, the system performs a preliminary extraction of the linear network, which is subsequently completed, refined and vectorized by means of an automatic procedure. Results on maps of different sources and scales are included. ----- Se presenta un sistema semi-automatico de vectorizacion de redes de objetos lineales (carreteras, rios, etc.) en mapas cartograficos digitalizados. En este sistema, la intervencion humana queda reducida a la seleccion grafica interactiva de los atributos de color de la informacion a obtener. Con estos datos, el sistema realiza una extraccion preliminar de la red lineal, que se completa, refina y vectoriza mediante un procedimiento automatico. Se presentan resultados de la aplicacion del sistema sobre imagenes digitalizadas de mapas de distinta procedencia y escala.; Comment: 12 pages with 13 figures, in Spanish

‣ FormCalc 8: Better Algebra and Vectorization

Nejad, B. Chokoufe; Hahn, T.; Lang, J. -N.; Mirabella, E.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 01/10/2013 Português
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We present Version 8 of the Feynman-diagram calculator FormCalc. New features include in particular significantly improved algebraic simplification as well as vectorization of the generated code. The Cuba Library, used in FormCalc, features checkpointing to disk for all integration algorithms.; Comment: 7 pages, LaTeX, proceedings contribution to ACAT 2013, Beijing, China, 16-21 May 2013

‣ Importance of Explicit Vectorization for CPU and GPU Software Performance

Dickson, Neil G.; Karimi, Kamran; Hamze, Firas
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 31/03/2010 Português
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Much of the current focus in high-performance computing is on multi-threading, multi-computing, and graphics processing unit (GPU) computing. However, vectorization and non-parallel optimization techniques, which can often be employed additionally, are less frequently discussed. In this paper, we present an analysis of several optimizations done on both central processing unit (CPU) and GPU implementations of a particular computationally intensive Metropolis Monte Carlo algorithm. Explicit vectorization on the CPU and the equivalent, explicit memory coalescing, on the GPU are found to be critical to achieving good performance of this algorithm in both environments. The fully-optimized CPU version achieves a 9x to 12x speedup over the original CPU version, in addition to speedup from multi-threading. This is 2x faster than the fully-optimized GPU version.; Comment: 17 pages, 17 figures

‣ Vectorization and Parallelization of the Adaptive Mesh Refinement N-body Code

Yahagi, Hideki
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/07/2005 Português
Relevância na Pesquisa
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In this paper, we describe our vectorized and parallelized adaptive mesh refinement (AMR) N-body code with shared time steps, and report its performance on a Fujitsu VPP5000 vector-parallel supercomputer. Our AMR N-body code puts hierarchical meshes recursively where higher resolution is required and the time step of all particles are the same. The parts which are the most difficult to vectorize are loops that access the mesh data and particle data. We vectorized such parts by changing the loop structure, so that the innermost loop steps through the cells instead of the particles in each cell, in other words, by changing the loop order from the depth-first order to the breadth-first order. Mass assignment is also vectorizable using this loop order exchange and splitting the loop into $2^{N_{dim}}$ loops, if the cloud-in-cell scheme is adopted. Here, $N_{dim}$ is the number of dimension. These vectorization schemes which eliminate the unvectorized loops are applicable to parallelization of loops for shared-memory multiprocessors. We also parallelized our code for distributed memory machines. The important part of parallelization is data decomposition. We sorted the hierarchical mesh data by the Morton order, or the recursive N-shaped order...

‣ A Novel Method for Vectorization

Birdal, Tolga; Bala, Emrah
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 04/03/2014 Português
Relevância na Pesquisa
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Vectorization of images is a key concern uniting computer graphics and computer vision communities. In this paper we are presenting a novel idea for efficient, customizable vectorization of raster images, based on Catmull Rom spline fitting. The algorithm maintains a good balance between photo-realism and photo abstraction, and hence is applicable to applications with artistic concerns or applications where less information loss is crucial. The resulting algorithm is fast, parallelizable and can satisfy general soft realtime requirements. Moreover, the smoothness of the vectorized images aesthetically outperforms outputs of many polygon-based methods; Comment: Prepared in Siggraph format, not published in a conference, 7 pages, 9 figures

‣ Vectorization of quantum operations and its use

Gilchrist, Alexei; Terno, Daniel R.; Wood, Christopher J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Português
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We give a detailed exposition of the "vectorized" notation for dealing with quantum operations. This notation is used to highlight the relationships between representations of completely-positive dynamics. Vectorization considerably simplifies the analysis of different methods of quantum process tomography, and enables us to derive compact representation of the investigated quantum operations in terms of the resulting data.; Comment: 12 pages, long-overdue modifications + corrections following the feedback

‣ TSLP Repository Supporting "Throttling Automatic Vectorization: When Less Is More"

Porpodas, Vasileios; Jones, Timothy M.
Fonte: Universidade de Cambridge Publicador: Universidade de Cambridge
Tipo: Relatório Formato: Plain text (README, licenses/GLPv3.txt, benchmarks/motivation.c), standard patch file, output of diff (TSLP.patch)
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This repository contains the code and data required to validate the results from the paper: "Throttling Automatic Vectorization: When Less Is More" Vasileios Porpodas and Timothy M. Jones 24th International Conference on Parallel Architectures and Compilation Techniques (PACT), 2015.; This record will be updated with publication details.; This record is licensed under a GPL version 3 licence.; This work was supported by the EPSRC [grant number EP/K026399/1]