1,354,457 research outputs found
Conformity-driven agents support ordered phases in the spatial public goods game
No full textWe investigate the spatial Public Goods Game in the presence of fitness-driven and conformity-driven agents. This framework usually considers only the former type of agents, i.e., agents that tend to imitate the strategy of their fittest neighbors. However, whenever we study social systems, the evolution of a population might be affected also by social behaviors as conformism, stubbornness, altruism, and selfishness. Although the term evolution can assume different meanings depending on the considered domain, here it corresponds to the set of processes that lead a system towards an equilibrium or a steady state. We map fitness to the agents' payoff so that richer agents are those most imitated by fitness-driven agents, while conformity-driven agents tend to imitate the strategy assumed by the majority of their neighbors. Numerical simulations aim to identify the nature of the transition, on varying the amount of the relative density of conformity-driven agents in the population, and to study the nature of related equilibria. Remarkably, we find that conformism generally fosters ordered cooperative phases and may also lead to bistable behaviors
Scale-free networks as an epiphenomenon of memory
No full textMany realistic networks are scale free, with small characteristic path lengths, high clustering, and power law in their degree distribution. They can be obtained by dynamical networks in which a preferential attachment process takes place. However, this mechanism is non-local, in the sense that it requires knowledge of the whole graph in order for the graph to be updated. Instead, if preferential attachment and realistic networks occur in physical systems, these features need to emerge from a local model. In this paper, we propose a local model and show that a possible ingredient (which is often underrated) for obtaining scale-free networks with local rules is memory. Such a model can be realised in solid-state circuits, using non-linear passive elements with memory such as memristors, and thus can be tested experimentally
Trapped surfaces and emergent curved space in the Bose-Hubbard model
No full textA Bose-Hubbard model on a dynamical lattice was introduced in previous work as a spin system analogue of emergent geometry and gravity. Graphs with regions of high connectivity in the lattice were identified as candidate analogues of spacetime geometries that contain trapped surfaces. We carry out a detailed study of these systems and show explicitly that the highly connected subgraphs trap matter. We do this by solving the model in the limit of no back-reaction of the matter on the lattice, and for states with certain symmetries that are natural for our problem. We find that in this case the problem reduces to a one-dimensional Hubbard model on a lattice with variable vertex degree and multiple edges between the same two vertices. In addition, we obtain a (discrete) differential equation for the evolution of the probability density of particles which is closed in the classical regime. This is a wave equation in which the vertex degree is related to the local speed of propagation of probability. This allows an interpretation of the probability density of particles similar to that in analogue gravity systems: matter inside this analogue system sees a curved spacetime. We verify our analytic results by numerical simulations. Finally, we analyze the dependence of localization on a gradual, rather than abrupt, falloff of the vertex degree on the boundary of the highly connected region and find that matter is localized in and around that region
A conceptual environmental and infrastructural risk assessment model to facilitate security management at major sporting events
No full textMajor sporting events have become increasingly important show cases as they provide an opportunity for a country to raise its profile. Owing to the fact that a major sporting event has a great deal of international appeal, it is not surprising to learn that law enforcement officers, and security and intelligence officers, are becoming increasingly concerned that activists, criminals and terrorists, will use major sporting events for their own means. Security and intelligence officers in particular are hard at work counteracting potential disruptions and are working with a range of other experts on developing a collectivist security partnership approach that can produce workable strategic security management policies. In order for this approach to be sustainable at an international level, those involved in the planning, organization and management of a major sporting event need to share and exchange information on a regular basis and give advice to and take advice from government representatives when necessary. It is important to note that managers employed by private sector companies need to work more closely with staff from the public sector, in order to ensure that the strategic security management policy that emerges is in fact sustainable. In particular, Internet service providers need to be more directly involved in providing online security and the general public need to be more adequately informed about the potential risks that are associated with the Internet. In order to safeguard those competing in or those attending a major sporting event, it is necessary for those involved in the organization of the event and the various sponsors, to introduce a number of security management initiatives that reduce the possibility of a man-made attack at the event. A conceptual environmental and infrastructural risk assessment model can be deployed to ensure that possible threats are identified and neutralized before they manifest. By putting in place robust counterterrorist measures, the authorities can ensure that a major sporting event is the cultural, social and economic success that it is supposed to be
Web marketing e social media nelle micro imprese artigiane della Basilicata
No full textThis paper analyzes the factors that influence the use of digital marketing and the barriers
that limit their use.Following the analysis of the literature, we have formulated research
hypotheses. They have been empirically tested on a sample of 42 craft microenterprise from
Basilicata, to which was provided a questionnaire by telephone interview. The obtained
results were analyzed together with the data provided by the AIDA database by contingency
tables and the calculation of the correlation coefficient.
The limits of the study are related to the salientness of the sample being analyzed.
However the study provides a contribution to the analysis of the factors affecting Internet
access by micro-businesses in Basilicata, suggesting managerial and public policy guidance
to increase competitiveness of handicraft industry
A general conformal-mapping approach to the optimum electrode design of coplanar waveguides with arbitrary cross section
No full textMathematica code for simulation of filament formation
No full textQuantum graph models for transport in filamentary switchingThis is the Mathematica code for the paper{Quantum graph models for transport in filamentary switching, A. A. Silva, F. Andrade, F. Caravelli.</p
Dall'osservazione della coordinazione familiare alla soddisfazione di coppia dei genitori e viceversa
No full text
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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