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101.
102.
Félix Gómez Mármol Christoph Sorge Ronald Petrlic Osman Ugus Dirk Westhoff Gregorio Martínez Pérez 《International Journal of Information Security》2013,12(2):67-82
The recent deployment of smart grids promises to bring numerous advantages in terms of energy consumption reduction in both homes and businesses. A more transparent and instantaneous measurement of electricity consumption through smart meters utilization leads to an enhancement in the ability of monitoring, controlling and predicting energy usage. Nevertheless, it also has associated drawbacks related to the privacy of customers, since such management might reveal their personal habits, which electrical appliances they are using at each moment, whether they are at home or not, etc. In this work, we present a privacy-enhanced architecture for smart metering aimed at tackling this threat by means of encrypting individual measurements while allowing the electricity supplier to access the aggregation of the corresponding decrypted values. 相似文献
103.
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: |
104.
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
105.
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
106.
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
107.
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
108.
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
109.
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
110.
Sonia M. Rogacheva Margarita J. Kuntcheva Ivan N. Panchev Tzvetan D. Obretenov 《European Food Research and Technology》1995,200(1):52-58
The influence of the water content, molar ratio, time and temperature on the formation of nondialysable melanoidins produced by the interaction ofl-ascorbic acid and glycine has been studied. The isolated polymers have been characterized by spectrum analysis and fractionated using gel chromatography. The rate constants of the reaction for temperatures of 90°C, 100°C and 110°C have been calculated and are (0.84±0.29) x 10?5 x s?1, (1.33±0.14) x 10?5 x s?1 and (5.30±0.37) x 10?5 x s?1 respectively. The activation energy of the reaction has been determined to be 106.07±32.47 kJ/mol. 相似文献