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71.
72.
In this experiment, intake of DK265 3-way corn hybrid by dairy cattle was compared specifically with intake 1) of its bm3 isogenic form, 2) of its 2 related single-way hybrids, and 3) of 2 controls that were registered hybrids of similar earliness. Both dry matter (DM) and lignin contents were similar in all hybrids except for the bm3 hybrid, which was less lignified. There was a tendency for lower starch content and, correlatively, higher neutral detergent fiber content in DK265 and in the 2 related single-way hybrids. Significant intake differences were observed between hybrids; the highest intake was recorded for the bm3 hybrid. Among normal hybrids, DK265 and one of its related single-way hybrids registered significantly higher intakes than other hybrids. Among normal hybrids, cell wall digestibility and/or lignin content did not explain all of the variations observed for intake, whereas the higher intake of DK265 bm3 could be related to its lower lignin content as compared with isogenic DK265. It was hypothesized that the higher intake observed for the DK265 hybrid was probably related to specific friability traits that are not relevantly measured through the usual tests used in corn breeding. 相似文献
73.
Gonçalves SI de Munck JC Verbunt JP Bijma F Heethaar RM Lopes da Silva F 《IEEE transactions on bio-medical engineering》2003,50(6):754-767
In vivo measurements of equivalent resistivities of skull (rho(skull)) and brain (rho(brain)) are performed for six subjects using an electric impedance tomography (EIT)-based method and realistic models for the head. The classical boundary element method (BEM) formulation for EIT is very time consuming. However, the application of the Sherman-Morrison formula reduces the computation time by a factor of 5. Using an optimal point distribution in the BEM model to optimize its accuracy, decreasing systematic errors of numerical origin, is important because cost functions are shallow. Results demonstrate that rho(skull)/rho(brain) is more likely to be within 20 and 50 rather than equal to the commonly accepted value of 80. The variation in rho(brain)(average = 301 omega x cm, SD = 13%) and rho(skull)(average = 12230 omega x cm, SD = 18%) is decreased by half, when compared with the results using the sphere model, showing that the correction for geometry errors is essential to obtain realistic estimations. However, a factor of 2.4 may still exist between values of rho(skull)/rho(brain) corresponding to different subjects. Earlier results show the necessity of calibrating rho(brain) and rho(skull) by measuring them in vivo for each subject, in order to decrease errors associated with the electroencephalogram inverse problem. We show that the proposed method is suited to this goal. 相似文献
74.
R. Cortenraad S. N. Ermolov A. W. Denier van der Gon V. G. Glebovskii H. H. Brongersma A. Manenschijn G. Gartner E. V. Belozerov 《Inorganic Materials》2001,37(7):673-677
Single-crystal tungsten substrates produced by electron-beam melting were cleaned by annealing in an oxygen atmosphere (10–3Pa, 1500°C) for a few hours to remove adsorbed carbon and by high-temperature ultrahigh-vacuum annealing (2 × 10–8Pa, 2500°C) for a few minutes to remove residual oxygen. The process was followed by low-energy ion scattering, Auger electron spectroscopy, and low-energy electron diffraction. The carbon and oxygen adsorbed on the surface of single-crystal tungsten were found to form ordered, oriented structures. The resultant high-purity, structurally perfect W substrates were used to study electron emission in the Ba/W and Re/W systems. 相似文献
75.
Cledja Rolim Alejandro C. Frery Eliana Almeida Evandro Costa Luiz Marcos Gonçalves 《The Visual computer》2007,23(6):409-418
In this work we propose a new approach for fast visualization and exploration of virtual worlds based on the use of cartographic
concepts and techniques. Versions of cartographic maps with different levels of details can be created by using a set of operations
named cartographic generalization. Cartographic generalization employs twelve operators and domain-specific knowledge, being the contribution of this work their
transposition to 3D virtual worlds. The architecture of a system for 3D generalization is proposed and the system is implemented.
Differently from traditional cartographic processes, we use artificial intelligence for both selecting the key objects and
applying the operators. As a case study, we present the simplification of the historical quarter of Recife (Brazil). 相似文献
76.
Luisa M. S. Gonçalves Cidália C. Fonte Eduardo N. B. S. Júlio Mario Caetano 《International journal of remote sensing》2013,34(9):2851-2867
The production of thematic maps from remotely sensed images requires the application of classification methods. A great variety of classifiers are available, producing frequently considerably different results. Therefore, the automatic extraction of thematic information requires the choice of the most appropriate classifier for each application. One of the main objectives of the research described in this article is to evaluate the performance of supervised classifiers using the information provided by the application of uncertainty measures to the testing sets, instead of statistical accuracy indices. The second main objective is to show that the information provided by the uncertainty measures for the training set may be used to assess and redefine the sample sites included in this set, in order to improve the classification results. To achieve the proposed objectives, two supervised classifiers, one probabilistic and another fuzzy, were applied to a very high spatial resolution (VHSR) image. The results show that similar conclusions on the classifiers’ performance are obtained with the uncertainty measures and the traditional accuracy indices obtained from error matrices. It is also shown that the redefinition of the training set based on the information provided by the uncertainty measures may generate more accurate outputs. 相似文献
77.
H. Gonçalves J. A. Gonçalves L. Corte-Real A. C. Teodoro 《International journal of remote sensing》2013,34(24):7936-7968
Automatic image registration is a process related to several application fields: remote sensing, medicine and computer vision, among others. Particularly in the field of remote sensing, the ever-increasing number of available satellite images requires automatic image registration methods, capable of correctly aligning a new image. An automatic image registration method – CHAIR (correlation- and Hough transform-based method of automatic image registration) – is proposed, the key concept of which relies on the ‘correlation image’ produced in both the horizontal and vertical directions. In particular, the computation of the distance of an identified diagonal brighter strip in the correlation image (through the Hough transform) to an offset (the main diagonal) allows for the determination of translational shifts and consequently control points. The set of obtained control points allows for the correction of several types of distortions. The geometric correction quality achieved by CHAIR was objectively evaluated through measures recently proposed, which allow for a more complete assessment of the obtained results. The CHAIR performance was evaluated on both synthetic and real data, with different spatial resolutions and spectral contents. CHAIR has been shown to be able to correctly align two images with a subpixel accuracy, having a priori a ‘gold standard’ image covering a considerable part of the image to be registered, and has also been shown to work for images of different sensors and/or different spectral bands, situations where traditional correlation methods often yield low and smooth peaks on the correlation surface. It is also able to account for elevation differences and to some extent for rotation and scale effects. Furthermore, it has been shown to have potential for registering synthetic aperture radar (SAR) with optical images. 相似文献
78.
Gon?alo Furtado 《Nexus Network Journal》2012,14(1):3-15
Similarities can certainly be found between systems research and computational sciences, and architecture and design. The
first pair deals with information, complex dynamics and organizations; the second pair is often understood as synthetic and
systemic. Postwar history recalls a sequence of exchanges between these fields; the aim of this paper is to highlight the
relevance of some exchanges and their contemporary legacy. In this connection, the first part briefly outlines the meaning
and history of the former disciplines, highlighting the strict circular models and how first-order cybernetics evolved towards
a second order. The second part points to some exchanges between systems research, computational sciences and art forms, as
well as to its architectural legacy. To a large extent, the current architectural interest in new sciences of emergence and
complexity is rooted in the early systems research approach. Both areas are possible root sources of a future, effective built
environment. 相似文献
79.
80.
Cayo Emilio Gonçalves Letícia Oliveira Laier Márcio José da Silva 《Catalysis Letters》2011,141(8):1111-1117