906 resultados para 2004-04-BS
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研究一种正交轮式移动车为载体的类人形机器人的建模与控制问题.首先基于分体建模的思想,采用机理建模和神经网络技术相结合的方法建立了动力学模型;然后依据该模型,提出一种新的基于 NN 的自适应 H_∞位置跟踪控制器,使鲁棒非线性 H_∞控制方法自然地与模型的直接自适应神经网络技术集成为一体,并证明了其鲁棒稳定性.最后,仿真研究验证了该方法的正确性和有效性.
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为避免繁琐的机器人示教过程,提出一种离线的基于波扩散方法的工业机器人路径规划算法.首先对机器人的工作空间离散化,针对工作空间中的障碍点和自由点进行二值标记;然后用波扩散方法对自由点进一步标记,并进行了路径搜索;最后,对波扩散法与深度优先算法路径搜索进行了比较.将该算法用于6-自由度工业机器人的仿真实验,得到了满意的效果.
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针对自由曲面透明体厚度测量,提出一种基于结构光机理的3D 视觉测量方法和系统结构,介绍了该方法的基本原理和测量系统实现技术,并给出了部分实验,证实了该方法的有效性。
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贵州水银洞(岩上)微细浸染型金矿产于贵州省贞丰县境内,是目前我国第一个成功地从原生硫化物矿石中商业性生产出金的微细浸染型金矿矿山。该矿床的矿体产于灰家堡背斜东段核部的上二叠统龙潭组地层中及其与中二叠统茅口组灰岩的接触带,呈几层基本平行排布的似层状和透镜状产出。金矿化主要赋存于硅化白云石化生物碎屑灰岩和泥灰岩(85%)和强硅化角砾状粘土岩(14%)中。
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We consider the problem of detecting a large number of different classes of objects in cluttered scenes. Traditional approaches require applying a battery of different classifiers to the image, at multiple locations and scales. This can be slow and can require a lot of training data, since each classifier requires the computation of many different image features. In particular, for independently trained detectors, the (run-time) computational complexity, and the (training-time) sample complexity, scales linearly with the number of classes to be detected. It seems unlikely that such an approach will scale up to allow recognition of hundreds or thousands of objects. We present a multi-class boosting procedure (joint boosting) that reduces the computational and sample complexity, by finding common features that can be shared across the classes (and/or views). The detectors for each class are trained jointly, rather than independently. For a given performance level, the total number of features required, and therefore the computational cost, is observed to scale approximately logarithmically with the number of classes. The features selected jointly are closer to edges and generic features typical of many natural structures instead of finding specific object parts. Those generic features generalize better and reduce considerably the computational cost of an algorithm for multi-class object detection.
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This article describes a model for including scene/context priors in attention guidance. In the proposed scheme, visual context information can be available early in the visual processing chain, in order to modulate the saliency of image regions and to provide an efficient short cut for object detection and recognition. The scene is represented by means of a low-dimensional global description obtained from low-level features. The global scene features are then used to predict the probability of presence of the target object in the scene, and its location and scale, before exploring the image. Scene information can then be used to modulate the saliency of image regions early during the visual processing in order to provide an efficient short cut for object detection and recognition.
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We formulate and interpret several multi-modal registration methods in the context of a unified statistical and information theoretic framework. A unified interpretation clarifies the implicit assumptions of each method yielding a better understanding of their relative strengths and weaknesses. Additionally, we discuss a generative statistical model from which we derive a novel analysis tool, the "auto-information function", as a means of assessing and exploiting the common spatial dependencies inherent in multi-modal imagery. We analytically derive useful properties of the "auto-information" as well as verify them empirically on multi-modal imagery. Among the useful aspects of the "auto-information function" is that it can be computed from imaging modalities independently and it allows one to decompose the search space of registration problems.
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2003
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A novel norvancomycin-bonded chiral stationary phase (NVC-CSP) was synthesized by using the chiral selector of norvancomycin. The chiral separation of enantiomers of several dansyl-amino acids by high-performance liquid chromatography (HPLC) in the reversed-phase mode is described. The effects of some parameters, such as organic modifier concentration, column temperature, pH and flow rate of the mobile phase, on the retention and enantioselectivity were investigated. The study showed that ionic, as well as hydrophobic interactions were engaged between the analyte and macrocycle in this chromatographic system. Increasing pH of buffers usually improved the chiral resolution for dansyl-alpha-amino-n-butyric acid (Dns-But), dansyl-methionine (Dns-Met) and dansyl-threonine (Dns-Thr), but not for dansyl-glutamic acid (Dns-Glu) which contains two carboxylic groups in its molecular structure. The natural logarithms of selectivity factors (In alpha) of all the investigated compounds depended linearly on the reciprocal of temperature (1/T), most processes of enantioseparation were controlled enthalpically. Interestingly, the process of enantioseparation for dansyl-threonine was enthalpy-controlled at pH of 3.5, while at pH of 7.0, it was entropy-controlled according to thermodynamic parameters Delta(R,S)DeltaHdegrees and Delta(R,S)DeltaSdegrees afforded by Van't Hoff plots. In order to get baseline separation for all the solutes researched, norvancomycin was also used as a chiral mobile phase additive. In combination with the NVC-CSP remarkable increases in enanselectivity were observed for all the compounds, as the result of a "synergistic" effect. (C) 2003 Elsevier B.V. All rights reserved.
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Este trabalho apresenta o uso da API HTTPUnit para recuperar dados de previsão do tempo utilizados na geração dos mapas a partir do site www.somarmeteorologia.com.br
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O projeto Análise de Redes com Sistemas de Informações Geográficas - ARSIG, tem como uma de suas metas a especialização de soluções de roteamento de veículos em uma dada área (rural ou urbana).
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O objetivo deste documento é apresentar as diretrizes básicas para escolha de um CMS tomando por base a experiência adquirida com o desenvolvimento do Agritempo.
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Este documento apresenta o esquema de tradução proposto para as telas de entrada de dados do banco de dados de experimentos em manejo de fertilizantes para cana-de-açúcar.
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Linguagem UML. Fase do projeto na UML: o diagrama de estados. Linguagem SDL. Comparação entre as duas técnicas apresentadas.
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Este trabalho apresenta as ferramentas e os procedimentos adotados para gerar e tornar disponível uma documentação eficiente de requisitos do sistema do projeto Agência de Informação Embrapa.