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71.
72.
Intelligent multisensor surveillance systems consist of several types of sensors, which are installed on fixed and mobile devices. These components provide a huge quantity of information that has to be contrasted, correlated and integrated in order to recognize and react on special situations. These systems work in highly dynamic environments, with severe security and robustness requirements. All these characteristics imply the need for distributed solutions. In these solutions, scattered components can decide and act with some degree of autonomy (for instance, if they become isolated), or cooperate and coordinate for a complete tracking of special situations. In order to cope with these requirements and to better structure the solution, we have decided to design surveillance system control as a multiagent system. This is done by applying an agent-orientated methodology, which is assessed with concrete scenarios. 相似文献
73.
In this paper, the effectiveness of the approximate motion equations of a flexible structure, obtained by the RitzKantorovich method, is analysed by using Lyapunov functions. The analysis, which is restricted to the case of a single flexible beam for the sake of simplicity, is carried out under the assumption that a partial dissipation is present, affecting only the first degrees of freedom of the system. By means of suitable Lyapunov functions, an overbounding estimate of the quadratic approximation error is determined as a decreasing function of the approximation order. The analysis is completed by considering the two ‘extreme’ cases: the theoretical absence of dissipation and the presence of structural dissipation, affecting all the infinite degrees of freedom. 相似文献
74.
Cntextual logic provides a mechanism to reason about modules.In this paper,this theory of modules if modules is extended to a context theory of classes where class is in the true spirit of object-oriented databases.The logic,referred to as CLOG,is class-based.CLOG supports class,object identity,multiple role of object, monotonic and non-monotonic inheritance of data and method,method factoring,views,derived and query classes.Views and derived classes are queries in themselves.Objects are pure data terms representing the ground instances of facts in the class.Object identity is a first class term in the logic.Inheritance is handled through delegation. 相似文献
75.
Mario Mariani Ugo Ravasio Armando Buttafava Antonio Faucitano 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,265(1):245-250
The effect of gamma irradiation in air is investigated in two thermoplastic polyesters (PET and PEN), in order to evaluate the influence of aromatic density and the role of oxygen on radiation resistance. EPR measurements were carried out to detect radical stability against oxygen permeation and to provide radical characterization. Viscometric data reveal a different behaviour between films and thick samples. Positron annihilation spectra show a decrease of ortho-positronium intensity, which is more marked in film samples. ortho-positronium lifetime does not depend on the radiation dose. 相似文献
76.
Jose Miguel Leiva-Murillo Antonio Artés-Rodríguez 《Neural Networks, IEEE Transactions on》2007,18(5):1433-1441
In this paper, we present a novel scheme for linear feature extraction in classification. The method is based on the maximization of the mutual information (MI) between the features extracted and the classes. The sum of the MI corresponding to each of the features is taken as an heuristic that approximates the MI of the whole output vector. Then, a component-by-component gradient-ascent method is proposed for the maximization of the MI, similar to the gradient-based entropy optimization used in independent component analysis (ICA). The simulation results show that not only is the method competitive when compared to existing supervised feature extraction methods in all cases studied, but it also remarkably outperform them when the data are characterized by strongly nonlinear boundaries between classes. 相似文献
77.
Relaxed stability and performance conditions for Takagi-Sugeno fuzzy systems with knowledge on membership function overlap. 总被引:1,自引:0,他引:1
Antonio Sala Carlos Ari?o 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2007,37(3):727-732
This correspondence presents a relaxation of some earlier linear matrix inequality (LMI) conditions, which allow setting up less conservative stability or performance conditions for Takagi-Sugeno fuzzy models. Unlike the previous literature, this correspondence takes into account the knowledge of the membership functions' shape by considering bounds on them and their cross products (interpreted as an overlap measure), introducing auxiliary LMI variables. Numerical examples illustrate the achieved improvements. 相似文献
78.
Testing of the multi-application small light water reactor (MASLWR) passive safety systems 总被引:1,自引:0,他引:1
Jose N. Reyes John Groome Brian G. Woods Eric Young Kent Abel You Yao Yeon Jong Yoo 《Nuclear Engineering and Design》2007,237(18):1999-2005
Experimental thermal hydraulic research has been conducted at Oregon State University for the purpose of assessing the performance of a new reactor design concept, the multi-application small light water reactor (MASLWR). The MASLWR is a pressurized light water reactor design with a net output of 35 MWe that uses natural circulation in both normal and transient operation. Due to its small size, portability and modularity, the MASLWR design is well suited to help fill the potential need for grid appropriate reactor designs for smaller electricity grids as may be found in developing or remote regions. The purpose of the OSU MASLWR test facility is to assess the operation of the MASLWR under normal full operating pressure and full temperature conditions and to assess the passive safety systems under transient conditions. The data generated by the testing program will be used to assess computer code calculations and to provide a better understanding of the thermal-hydraulic phenomena in the design of the MASLWR NSSS. During this testing program, four tests were conducted at the OSU MASLWR test facility. These tests included one design basis accident and one beyond design basis accident. During the performance of these tests, plant operations to include start up, normal operation and shut down evolutions were demonstrated successfully. 相似文献
79.
The microstructural evolution during the hot rolling of coarse grain sized austenite has been modeled considering all the microstructural mechanisms (dynamic, static and metadynamic recrystallization, strain induced precipitation) that can take place during an industrial TSDR production of three Nb microalloyed steels. Based on the results obtained from the model, processing maps have been drawn for 0.02%, 0.035% and 0.05% Nb microalloyed steels. Optimum processing conditions to exploit all the benefits of the Nb microalloying have been defined considering a final gauge thickness range between 1.5 and 12.65 mm. In addition, and facing the difficulties present in the production of thick hot strip, several alternative thermomechanical schedules are proposed, which would originate microstructures with a suitable combination of homogeneity and retained strain prior to transformation. 相似文献
80.
Jose R. Rios Viqueira Nikos A. Lorentzos 《The VLDB Journal The International Journal on Very Large Data Bases》2007,16(2):179-200
An SQL extension is formalized for the management of spatio-temporal data, i.e. of spatial data that evolves with respect
to time. The extension is dedicated to applications such as topography, cartography, and cadastral systems, hence it considers
discrete changes both in space and in time. It is based on the rigid formalization of data types and of SQL constructs. Data types are defined in terms of time and
spatial quanta. The SQL constructs are defined in terms of a kernel of few relational algebra operations, composed of the well-known operations of the 1NF model and of two more, Unfold and Fold. In conjunction with previous work, it enables the uniform management of 1NF structures that may contain not only spatio-temporal
but also either purely temporal or purely spatial or conventional data. The syntax and semantics of the extension is fully
consistent with the {SQL:2003} standard. 相似文献