Previous studies mostly assume deterministic interactions among neighboring individuals for games on graphs. In this paper, we relax this assumption by introducing stochastic interactions into the spatial Prisoner’s ...
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Previous studies mostly assume deterministic interactions among neighboring individuals for games on graphs. In this paper, we relax this assumption by introducing stochastic interactions into the spatial Prisoner’s dilemma game, and study the effects of interaction stochasticity on the evolution of cooperation. Interestingly, simulation results show that there exists an optimal region of the intensity of interaction resulting in a maximum cooperation level. Moreover, we find good agreement between simulation results and theoretical predictions obtained from an extended pair-approximation method. We also show some typical snapshots of the system and investigate the mean payoffs for cooperators and defectors. Our results may provide some insight into understanding the emergence of cooperation in the real world where the interactions between individuals take place in an intermittent manner.
Locality data available for many, if not most, species of Neotropical frogs are based on written descriptions of the collecting sites, not on GPS device determined coordinate data. The pre-GPS device data are imprecis...
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Locality data available for many, if not most, species of Neotropical frogs are based on written descriptions of the collecting sites, not on GPS device determined coordinate data. The pre-GPS device data are imprecise relative to GPS data. Niche modeling is a powerful technique for predicting geographic distributions that provides the best results when the locality data are precise. The purpose of this study is to determine whether imprecise historical locality data are sufficient such that niche modeling techniques can yield realistic new insights to species-level distributions. Two sets of frogs of the genus Leptodactylus that have known different kinds of distributions are evaluated: two species with broad, presumably continuous distributions, and four species known to occur in patchy, disjunct habitats in South America. BIOCLIM, a presence-only environmental niche modeling algorithm,was used to define suitable occupancy areas based on multiple sets of environmental parameters that include: monthly mean, max, and min temperatures, and monthly precipitation. A Nature Conservancy — Natureserve ecoregion layer and a high resolution elevation layer were also included in the analyses. Our analyses yield new realistic insights and questions regarding distributions of the Leptodactylus species we evaluated. We recommend incorporation of the Nature Conservancy — Natureserve layer to evaluate Neotropical distributions, as the layer gave much more robust results than use of only the climatic variable analyses.
Multicommunity population systems may reach a consensus state where the fractions of each species in different communities agree on a common value. In this paper, by analyzing the evolutionary dynamics based on an ext...
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Multicommunity population systems may reach a consensus state where the fractions of each species in different communities agree on a common value. In this paper, by analyzing the evolutionary dynamics based on an extended replicator equation incorporating community effects, the consensus problem of population systems with n communities is studied. In particular, the simple case of two communities is investigated in detail. In general, for n communities, a sufficient and necessary condition for population systems to reach a consensus of coexistent state is provided. Regarding the population dynamics for the four different types of games, whether the population systems can achieve consensus is determined. The dynamics of community-structured populations shows richer features than nonstructured populations, and some nontrivial phenomena arising from different community-structured population systems are illustrated with concrete numerical examples.
In order to group web pages, vector space models for analyzing documents similarities have been often used variously. However, they are not used for analyzing link structures, partly because they are complex and links...
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In order to group web pages, vector space models for analyzing documents similarities have been often used variously. However, they are not used for analyzing link structures, partly because they are complex and links do not necessarily satisfy the similarity relation. If we can devise vector space models for link structures, we can combine them with those models for document similarity in order to develop the unified basis for grouping Web pages. In this paper, we present a vector space model for link structures, based on the notion of link vectors, the specifically designed characteristic vectors for link structures. We also discuss the extension of this model to the model called content-link vector space model, which can treat document information and link information of Web pages in a unified way. The preliminary experiments show that the models show good performance even when document information is ignored.
The Dicke model describes N qubits (or two-level atoms) homogeneously coupled to a bosonic mode. Here we examine an open-system realization of the Dicke model, which contains critical and chaotic behaviors. In particu...
The Dicke model describes N qubits (or two-level atoms) homogeneously coupled to a bosonic mode. Here we examine an open-system realization of the Dicke model, which contains critical and chaotic behaviors. In particular, we extend this model to include an additional open transport qubit (coupled to the bosonic mode) for passive and active measurements. We illustrate how the scaling (in the number of qubits N) of the super-radiant phase transition can be observed in both current and current-noise measurements through the transport qubit. Using a master equation, we also investigate how the phase transition is affected by the back action from the transport qubit and losses in the cavity. In addition, we show that the nonintegrable quantum chaotic character of the Dicke model is retained in an open-system environment. We propose how all of these effects could been seen in a circuit-QED system formed from an array of superconducting qubits, or an atom chip, coupled to a quantized resonant cavity (e.g., a microwave transmission line).
This article presents a multiscale simulation approach starting at the molecular level for the adsorption process development. A grand canonical Monte Carlo method is used for the prediction of adsorption isotherms of...
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This article presents a multiscale simulation approach starting at the molecular level for the adsorption process development. A grand canonical Monte Carlo method is used for the prediction of adsorption isotherms of methanol on an activated carbon at the molecular level. The adsorption isotherms obtained in the linear region （or adsorption constant） are exploited as a model parameter required for the adsorption process simulation. The adsorption process model described by a set of partial differential equations （PDEs） is solved by using the conservation element and solution element method, which produces a fast and an accurate numerical solution to PDEs. The simulation results obtained from the adsorption constant estimated at the molecular level are in good agreement with the experimental results of the pulse response. The systematical multiscale simulation approach addressed in this study may be useful to accelerate the adsorption process development by reducing the number of experiments.
This paper presents popular unsupervised clustering algorithms based on neuro-fuzzy, fuzzy c-means (FCM) and agglomerative techniques. The purpose of this paper is to provide clustering methods able to cluster the dat...
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This paper presents popular unsupervised clustering algorithms based on neuro-fuzzy, fuzzy c-means (FCM) and agglomerative techniques. The purpose of this paper is to provide clustering methods able to cluster the data patterns without a priori information about the number of clusters. We will show that it is possible to reconcile the FCM algorithm with the unsupervised clustering algorithms. Finally, to show the efficiencies of these algorithms, we will apply them to model the behaviour of uncertain system.
Localization is one of the most important functions for the mobile robot navigation. Most of previous position estimation methods calculate current position and orientation of mobile robot by applying various localiza...
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Localization is one of the most important functions for the mobile robot navigation. Most of previous position estimation methods calculate current position and orientation of mobile robot by applying various localization schemes with the information obtained from internal sensors which are set on the mobile robot, or by recognizing an artificial landmark attached on the environment. Several drawbacks about them have been brought up. To avoid these inconvenient, a new localization method that calculate in real time the absolute position of the mobile robot by using external camera fixed on the ceiling in the indoor environment is proposed. Besides, this approach provide a low expensive solution using a Webcam. The effectiveness of the proposed localization algorithm is demonstrated through the experiments.
In this paper we present the architecture for the Personal Autonomic Desktop Manager, a self managing application designed to act on behalf of the user in several aspects: protection, healing, optimization and configu...
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In this paper we present the architecture for the Personal Autonomic Desktop Manager, a self managing application designed to act on behalf of the user in several aspects: protection, healing, optimization and configuration. The overall goal of this research is to improve the correlation of the autonomic self{sup}* properties and doing so also enhance the overall self-management capacity of the desktop (autonomicity). We introduce the Circulatory Computing (CC) model, a self-managing system initiative based on the biological metaphor of the cardiovascular system, and use its concepts in the design and implementation of the architecture.
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