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101.
Dimas?Martínez?MoreraEmail author Paulo?Cezar?Carvalho Luiz?Velho 《The Visual computer》2008,24(12):1025-1037
This paper discusses the problem of modeling on triangulated surfaces with geodesic curves. In the first part of the paper
we define a new class of curves, called geodesic Bézier curves, that are suitable for modeling on manifold triangulations. As a natural generalization of Bézier curves, the new curves
are as smooth as possible. In the second part we discuss the construction of C
0 and C
1 piecewise Bézier splines. We also describe how to perform editing operations, such as trimming, using these curves. Special
care is taken to achieve interactive rates for modeling tasks. The third part is devoted to the definition and study of convex
sets on triangulated surfaces. We derive the convex hull property of geodesic Bézier curves.
相似文献
Luiz VelhoEmail: |
102.
Nowadays, the use of Radio Frequency Identification (RFID) systems in industry and stores has increased. Nevertheless, some
of these systems present privacy problems that may discourage potential users. Hence, high confidence and effient privacy
protocols are urgently needed. Previous studies in the literature proposed schemes that are proven to be secure, but they
have scalability problems. A feasible and scalable protocol to guarantee privacy is presented in this paper. The proposed
protocol uses elliptic curve cryptography combined with a zero knowledge-based authentication scheme. An analysis to prove
the system secure, and even forward secure is also provided.
This work is supported by the Generalitat de Catalunya under Grant No. FIC 2007FIC 00880, and the projects of the Spanish
MCyT MTM2007-66842-C02-02 and TIN2006-15662-C02-02. 相似文献
103.
Juan José Martín‐Romero Montserrat Gil‐Martínez Mario García‐Sanz 《国际强度与非线性控制杂志
》2009,19(17):1959-1971
》2009,19(17):1959-1971
This paper describes an analytical formulation to compute quantitative feedback theory (QFT) bounds in one‐degree‐of‐freedom feedback control problems. The new approach is based on envelope curves and shows that a QFT control specification can be expressed as a family of circumferences. Then, the controller bound is defined by the envelope curve of this family and can be obtained as an analytical function. This offers the possibility of studying the QFT bounds in an analytical way with several useful properties. Gridding methods are avoided, resulting in a lower computational effort procedure. The new formulation improves the accuracy of previous methods and allows the designer to calculate multivalued bounds. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
104.
GLSV: Graphics library stereo vision for OpenGL 总被引:1,自引:0,他引:1
This work proposes the development of an auxiliary library for use with OpenGL, to facilitate the creation of graphic applications
incorporating stereoscopic representation. This library, christened graphics library stereo vision (GLSV), is designed to
remove all calculations involving knowledge of stereo vision theory from the task performed by the programmer without the
latter having to change the way he/she has been working with the OpenGL library. The GLSV is distributed under the terms of
the GNU Library General Public License agreement. 相似文献
105.
Manuel J. Betancur Fajith Martínez Carlos Ocampo Jaime A. Moreno Germán Buitrón Iván Moreno-Andrade 《Simulation Modelling Practice and Theory》2009,17(4):680-691
This work proposes a mathematical model for the acclimatization process of a bioreactor treating toxic wastewater. Experimental data was used to identify the changing kinetic parameters of the model as acclimatization progresses. It was found that only one key parameter, the specific biomass growth rate function, changed during the acclimatization process. Therefore, an acclimatization model was proposed to explain the changes of this parameter. 相似文献
106.
Partial discharges are a transient phenomena whose measurement is remarkably important for electrical equipment diagnosis and maintenance. These discharges appear in the measurement circuit as very narrow current pulses of some nanoseconds. Therefore, discharge pulse detection is a particularly difficult problem, especially because they are superposed on the high voltage waveforms that cause them. In this paper, we present an inductively coupled probe able to measure this physical phenomenon by means of a very simple and inexpensive device that can be installed in the equipment under test. After modeling the probe, its response will be compared to that of commercial devices using both calibrated discharges and partial discharges occurring at real power. 相似文献
107.
An automatic three-dimensional spectrogoniometer is presented. The wavelength of ligth and angles of incidence and observation are variable, making it capable of performing different optical characterizations in an integrated way. 相似文献
108.
Bravo-Montes J. A. Martín-Toledano A. Sánchez-Macián A. Ruano O. Garcia-Herrero F. 《The Journal of supercomputing》2022,78(6):8056-8080
The Journal of Supercomputing - CMOS technology is facing physical limitations in scaling the manufacturing process. Therefore, to deepen the development of better designs in a smaller area, it is... 相似文献
109.
110.
Roberto C. Dante Francisco M. Sánchez-Arévalo Lazaro Huerta Florinella Muñoz-Bisesti Diana Marquez Pablo Martín-Ramos 《Fullerenes, Nanotubes and Carbon Nanostructures》2017,25(11):630-636
Polymeric carbon nitride was synthesized from urea and doped with Cu and Fe to act as co-catalysts. The material doped with Fe was a new composite material composed of Fe(III) oxides (acting as a co-catalyst) wrapped by the polymer layers and amorphous carbon. Furthermore, the copper doped material was described in a previous report. The photocatalytic degradation of the azo dye direct blue 1 (DB) was studied using as photocatalysts: pure carbon nitride (CN), carbon nitride doped with Cu (CN-Cu) and carbon nitride doped with Fe (CN-Fe). The catalysts were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), by X-ray photoelectron spectroscopy (XPS) and Brunauer–Emmett–Teller method (BET), etc. The adsorption phenomenon was studied using the Langmuir and Freundlich models. For the kinetic study, a solution of 500 mg L?1 of DB1 was treated with each catalyst, visible light and H2O2. The dye concentration was measured by spectrophotometry at the wavelength of 565 nm, and the removal of the total organic content (TOC) was quantified. BET analysis yielded surface areas of 60.029, 20.116 and 70.662 m2g?1 for CN, CN-Cu and CN-Fe, respectively. The kinetics of degradation were pseudo-first order, whose constants were 0.093, 0.039 and 0.110 min?1 for CN, CN-Cu and CN-Fe, respectively. The total organic carbon (TOC) removal reached the highest value of 14.46% with CN-Fe. 相似文献