A General Framework for Complex Network Applications

Complex network theory has been applied to solving practical problems from different domains. In this paper, we present a general framework for complex network applications. The keys of a successful application are a thorough understanding of the real system and a correct mapping of complex network theory to practical problems in the system. Despite of certain limitations discussed in this paper, complex network theory provides a foundation on which to develop powerful tools in analyzing and optimizing large interconnected systems.Comment: 8 page

A Filtering-based General Approach to Learning Rational Constraints of Epistemic Graphs

Epistemic graphs generalize the epistemic approach to probabilistic argumentation and tackle the uncertainties in and between arguments. A framework was proposed to generate epistemic constraints from data using a two-way generalization method in the perspective of only considering the beliefs of participants without considering the nature of relations represented in an epistemic graph. The deficiency of original framework is that it is unable to learn rules using tighter constraints, and the learnt rules might be counterintuitive. Meanwhile, when dealing with more restricted values, the filtering computational complexity will increase sharply, and the time performance would become unreasonable. This paper introduces a filtering-based approach using a multiple-way generalization step to generate a set of rational rules based on both the beliefs of each agent on different arguments and the epistemic graph corresponding to the epistemic constraints. This approach is able to generated rational rules with multiple restricted values in higher efficiency. Meanwhile, we have proposed a standard to analyze the rationality of a dataset based on the postulates of deciding rational rules. We evaluate the filtering-based approach on two suitable data bases. The empirical results show that the filtering-based approach performs well with a better efficiency comparing to the original framework, and rules generated from the improved approach are ensured to be rational.Comment: 19 pages, 9 figures, submitted to SAC 202

Herramienta para la gestion de recursos del servicio PMR del Aeropuerto de Barcelona

This work is about to design a program for the management of resources of the assistance service to passengers with reduced mobility (PRM) in the airport of Barcelona-El Prat. The current problem that be found of the service is, too many non-compliance of waiting times due to insufficient resources, because there is a large amount services are unforeseen. This derives to a malfunctioning of the service and it shows a bad image of the airport. Therefore, the principal objective of the program is to improve the current service, for this, it must be able to determinate the necessary resources to cover all the services, both predicted and unforeseen services, in each terminal and in each specific hour. Also, it needs to develop an algorithm which can make the system works with more efficiency. In order to make the program works with more accuracy, it is necessary to make statistical studies analyzing the historical data provided by AENA. Another study of this service has been used in order to know the arrival probability distributions of the passengers and times of service in each stand in the airport. The possible factors that can influence the services and the previous considerations to facilitate the simulations are detailed. It presents the instruction manual of the program, explaining all the functionalities, the main criterion of algorithms that have been used to determine the necessary agents, and the assignment of service resources. Once the simulations are done, it verifies that the program works correctly by doing two simple tests. By comparing the results obtained from the simulations with the real data, can evaluate that program is applicable in real case practices, and it can optimize the available resources, but should make other studies more deepened

Anisotropic optical properties of rhombohedral and tetragonal thin film BiFeO3_3 phases

The anisotropic optical properties of multiferroic BiFeO$_3$ thin films have been determined with Mueller matrix ellipsometry at room-temperature. The full dielectric tensors of tetragonal-like and rhombohedral-like BiFeO$_3$ phases epitaxially grown on LaAlO$_3$ and SrTiO$_3$ single crystal substrates, respectively, within the spectral range of 0.6 and 6.5 eV are reported. Strain-driven anisotropy changes and transition shifts are observed as well as evidence of sub-band gap many-particle excitations are found. The transition shifts, mostly to higher energies for the highly strained tetragonal-like BiFeO$_3$ phase on LaAlO$_3$, are indicative of band structure differences. Additionally, optical modelling, confirmed by piezoelectric force microscopy studies, revealed that the average polarization direction of bivariant BiFeO$_3$ on LaAlO$_3$ is not parallel to the crystallographic [001] direction but tilted by about $7^{\circ}$. Spectral weight analyses reveal phase-dependent differences underlining that theoretical calculations of optical spectra need further improvement to appropriately account for electronic and excitonic correlations to fully understand multiferroic BiFeO$_3$.Comment: 7 pages, 5 figure

Empirical studies on the network of social groups: the case of Tencent QQ

Participation in social groups are important but the collective behaviors of human as a group are difficult to analyze due to the difficulties to quantify ordinary social relation, group membership, and to collect a comprehensive dataset. Such difficulties can be circumvented by analyzing online social networks. In this paper, we analyze a comprehensive dataset obtained from Tencent QQ, an instant messenger with the highest market share in China. Specifically, we analyze three derivative networks involving groups and their members -- the hypergraph of groups, the network of groups and the user network -- to reveal social interactions at microscopic and mesoscopic level. Our results uncover interesting behaviors on the growth of user groups, the interactions between groups, and their relationship with member age and gender. These findings lead to insights which are difficult to obtain in ordinary social networks.Comment: 18 pages, 9 figure