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91.
Miguel A. Martínez-del-Amor Luis F. Macías-Ramos Luis Valencia-Cabrera Mario J. Pérez-Jiménez 《Natural computing》2016,15(4):565-573
Population Dynamics P systems are a type of multienvironment P systems that serve as a formal modeling framework for real ecosystems. The accurate simulation of these probabilistic models, e.g. with Direct distribution based on Consistent Blocks Algorithm, entails large run times. Hence, parallel platforms such as GPUs have been employed to speedup the simulation. In 2012, the first GPU simulator of PDP systems was presented. However, it was able to run only randomly generated PDP systems. In this paper, we present current updates made on this simulator, involving an input modu le for binary files and an output module for CSV files. Finally, the simulator has been experimentally validated with a real ecosystem model, and its performance has been tested with two high-end GPUs: Tesla C1060 and K40. 相似文献
92.
Logan Molyneux Krishnan Vasudevan Homero Gil de Zúñiga 《Journal of Computer-Mediated Communication》2015,20(4):381-399
Recent research suggests that social interactions in video games may lead to the development of community bonding and prosocial attitudes. Building on this line of research, a national survey of U.S. adults finds that gamers who develop ties with a community of fellow gamers possess gaming social capital, a new gaming‐related community construct that is shown to be a positive antecedent in predicting both face‐to‐face social capital and civic participation. 相似文献
93.
94.
The evaluation of the emergent behaviour in complex systems requires an analytical framework which allows the observation of different phenomena that take place at different levels. In order to observe the dynamics of complex systems, it is necessary to perform simulations so that both local and the emergent behaviour can be observed. To this end, the way in which complex system simulators are built must be examined so that it will be feasible to model large scale scenarios. In this paper, the use of Model Driven Engineering methodology is proposed to deal with this issue. Among other benefits, it is shown that this methodology allows the representation and simulation of a complex system providing support for the analysis. This analysis is supported by a metamodel which describes the system components that are under study. The application of this methodology to the development of large scale simulators is explored through a case study. This case study analyses a complex socio-technical system: a power grid. 相似文献
95.
This paper proposes a methodology to compute quadratic performance bounds when the closed loop poles of a discrete-time multivariable control loop are confined to a disk, centred at the origin, and with radius less than one. The underlying philosophy in this constraint is to avoid certain undesirable dynamic features which arise in quadratic optimal designs. An expression for the performance loss due to the pole location constraint is also provided. Using numerical examples, we show that the performance loss is compensated by an improved transient performance, specially visible in the control signals. 相似文献
96.
Artificial institutions: a model of institutional reality for open multiagent systems 总被引:2,自引:0,他引:2
Nicoletta Fornara Francesco Viganò Mario Verdicchio Marco Colombetti 《Artificial Intelligence and Law》2008,16(1):89-105
Software agents’ ability to interact within different open systems, designed by different groups, presupposes an agreement
on an unambiguous definition of a set of concepts, used to describe the context of the interaction and the communication language
the agents can use. Agents’ interactions ought to allow for reliable expectations on the possible evolution of the system;
however, in open systems interacting agents may not conform to predefined specifications. A possible solution is to define
interaction environments including a normative component, with suitable rules to regulate the behaviour of agents. To tackle
this problem we propose an application-independent metamodel of artificial institutions that can be used to define open multiagent
systems. In our view an artificial institution is made up by an ontology that models the social context of the interaction,
a set of authorizations to act on the institutional context, a set of linguistic conventions for the performance of institutional
actions and a system of norms that are necessary to constrain the agents’ actions. 相似文献
97.
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
98.
Frank-Michael Schleif Mathias Lindemann Mario Diaz Peter Maaß Jens Decker Thomas Elssner Michael Kuhn Herbert Thiele 《Computing and Visualization in Science》2009,12(4):189-199
Automatic classification of high-resolution mass spectrometry data has increasing potential to support physicians in diagnosis of diseases like cancer. The proteomic data exhibit variations among different disease states. A precise and reliable classification of mass spectra is essential for a successful diagnosis and treatment. The underlying process to obtain such reliable classification results is a crucial point. In this paper such a method is explained and a corresponding semi automatic parameterization procedure is derived. Thereby a simple straightforward classification procedure to assign mass spectra to a particular disease state is derived. The method is based on an initial preprocessing stage of the whole set of spectra followed by the bi-orthogonal discrete wavelet transform (DWT) for feature extraction. The approximation coefficients calculated from the scaling function exhibit a high peak pattern matching property and feature a denoising of the spectrum. The discriminating coefficients, selected by the Kolmogorov–Smirnov test are finally used as features for training and testing a support vector machine with both a linear and a radial basis kernel. For comparison the peak areas obtained with the it ClinProt-System 1 [33] were analyzed using the same support vector machines. The introduced approach was evaluated on clinical MALDI-MS data sets with two classes each originating from cancer studies. The cross validated error rates using the wavelet coefficients where better than those obtained from the peak areas2. 相似文献
99.
Daniel Díaz-Pernil Mario J. Pérez-Jiménez Álvaro Romero-Jiménez 《Natural computing》2009,8(4):797-806
In the framework of P systems, it is known that the construction of exponential number of objects in polynomial time is not
enough to efficiently solve NP-complete problems. Nonetheless, it could be sufficient to create an exponential number of membranes in polynomial time. Working
with P systems whose membrane structure does not increase in size, it is known that it is not possible to solve computationally
hard problems (unless P = NP), basically due to the impossibility of constructing exponential number of membranes, in polynomial time, using only evolution,
communication and dissolution rules. In this paper we show how a family of recognizer tissue P systems with symport/antiport
rules which solves a decision problem can be efficiently simulated by a family of basic recognizer P systems solving the same
problem. This simulation allows us to transfer the result about the limitations in computational power, from the model of
basic cell-like P systems to this kind of tissue-like P systems. 相似文献
100.
Gil Francopoulo Nuria Bel Monte George Nicoletta Calzolari Monica Monachini Mandy Pet Claudia Soria 《Language Resources and Evaluation》2009,43(1):57-70
Optimizing the production, maintenance and extension of lexical resources is one the crucial aspects impacting natural language
processing (NLP). A second aspect involves optimizing the process leading to their integration in applications. With this
respect, we believe that a consensual specification on monolingual, bilingual and multilingual lexicons can be a useful aid
for the various NLP actors. Within ISO, one purpose of Lexical Markup Framework (LMF, ISO-24613) is to define a standard for
lexicons that covers multilingual lexical data.
相似文献
Claudia SoriaEmail: |