33 research outputs found
Optimal percolation on multiplex networks
Optimal percolation is the problem of finding the minimal set of nodes such
that if the members of this set are removed from a network, the network is
fragmented into non-extensive disconnected clusters. The solution of the
optimal percolation problem has direct applicability in strategies of
immunization in disease spreading processes, and influence maximization for
certain classes of opinion dynamical models. In this paper, we consider the
problem of optimal percolation on multiplex networks. The multiplex scenario
serves to realistically model various technological, biological, and social
networks. We find that the multilayer nature of these systems, and more
precisely multiplex characteristics such as edge overlap and interlayer
degree-degree correlation, profoundly changes the properties of the set of
nodes identified as the solution of the optimal percolation problem.Comment: 7 pages, 5 figures + appendi
Escaping kinetic traps using non-reciprocal interactions
Kinetic traps are a notorious problem in equilibrium statistical mechanics,
where temperature quenches ultimately fail to bring the system to low energy
configurations. Using multifarious self-assembly as a model system, we
introduce a mechanism to escape kinetic traps by utilizing non-reciprocal
interactions between components. Introducing non-equilibrium effects offered by
broken action-reaction symmetry in the system, we can push the trajectory of
the system out of arrested dynamics. The dynamics of the model is studied using
tools from the physics of interfaces and defects. Our proposal can find
applications in self-assembly, glassy systems and systems with arrested
dynamics
Embedding-aided network dismantling
Optimal percolation concerns the identification of the minimum-cost strategy
for the destruction of any extensive connected components in a network.
Solutions of such a dismantling problem are important for the design of optimal
strategies of disease containment based either on immunization or social
distancing. Depending on the specific variant of the problem considered,
network dismantling is performed via the removal of nodes or edges, and
different cost functions are associated to the removal of these microscopic
elements. In this paper, we show that network representations in geometric
space can be used to solve several variants of the network dismantling problem
in a coherent fashion. Once a network is embedded, dismantling is implemented
using intuitive geometric strategies. We demonstrate that the approach well
suits both Euclidean and hyperbolic network embeddings. Our systematic analysis
on synthetic and real networks demonstrates that the performance of
embedding-aided techniques is comparable to, if not better than, the one of the
best dismantling algorithms currently available on the market.Comment: 13 pages, 5 figures, 1 table + SM available at
https://cgi.luddy.indiana.edu/~filiradi/Mypapers/SM_geo_percolation.pd
Observability transition in multiplex networks
We extend the observability model to multiplex networks. We present mathematical frameworks, valid under the treelike ansatz, able to describe the emergence of the macroscopic cluster of mutually observable nodes in both synthetic and real-world multiplex networks. We show that the observability transition in synthetic multiplex networks is discontinuous. In real-world multiplex networks instead, edge overlap among layers is responsible for the disappearance of any sign of abruptness in the emergence of the the macroscopic cluster of mutually observable nodes
Generic structure of introductions in entrepreneurship research articles / Fatemeh Naderi Osat
The purpose of the present study is twofold. Firstly it seeks to find the generic structures that are inherent in the introduction sections of entrepreneurship research articles and secondly it investigates the role of experiential metafunction and its distribution in realization of obligatory generic elements that are found in the data.
The approach applied is a combination of Halliday and Hasan’s (1989) model of genre analysis to find the generic structure potential (GSP) of the introduction sections as well as Halliday’s (1994) model of transitivity analysis to find the typicality of the process types and their contribution in the realization of the obligatory elements.
The corpus comprises 20 research article introduction sections that are published from 2010 onward in the Journal of Small Business and Entrepreneurship and Small Business and Enterprise Development.
The analysis reveals that 13 types of generic elements might occur in the entrepreneurship research articles introductions. Two of these elements such as ‘Purpose of study’ and ‘Previous study’ element are present in the whole data while others are found to be optional. Based on the obligatory, optional and recursive elements found on the data, the model of Generic Structure Potential (GSP) of the entrepreneurship research article’s introduction sections is proposed. Moreover, in the second phase of analysis the findings reveal that the typicality of the process types within each obligatory element is mostly in line with the function that each obligatory generic element fulfills in that particular genre. As an instance, in the present study, the ‘purpose of study’ element is mostly recognized with Mental processes and Relational processes while the ‘Previous study’ element is highly characterized with Material and Mental processes
Non-reciprocal multifarious self-organization
A hallmark of living systems is the ability to employ a common set of building blocks that can self-organize into a multitude of different structures. This capability can only be afforded in non-equilibrium conditions, as evident from the energy-consuming nature of the plethora of such dynamical processes. To achieve automated dynamical control of such self-assembled structures and transitions between them, we need to identify the fundamental aspects of non-equilibrium dynamics that can enable such processes. Here we identify programmable non-reciprocal interactions as a tool to achieve such functionalities. The design rule is composed of reciprocal interactions that lead to the equilibrium assembly of the different structures, through a process denoted as multifarious self-assembly, and non-reciprocal interactions that give rise to non-equilibrium dynamical transitions between the structures. The design of such self-organized shape-shifting structures can be implemented at different scales, from nucleic acids and peptides to proteins and colloids
k-core structure of real multiplex networks
Multiplex networks are convenient mathematical representations for many
real-world -- biological, social, and technological -- systems of interacting
elements, where pairwise interactions among elements have different flavors.
Previous studies pointed out that real-world multiplex networks display
significant inter-layer correlations -- degree-degree correlation, edge
overlap, node similarities -- able to make them robust against random and
targeted failures of their individual components. Here, we show that
inter-layer correlations are important also in the characterization of their
-core structure, namely the organization in shells of nodes with
increasingly high degree. Understanding -core structures is important in the
study of spreading processes taking place on networks, as for example in the
identification of influential spreaders and the emergence of localization
phenomena. We find that, if the degree distribution of the network is
heterogeneous, then a strong -core structure is well predicted by
significantly positive degree-degree correlations. However, if the network
degree distribution is homogeneous, then strong -core structure is
due to positive correlations at the level of node similarities. We reach our
conclusions by analyzing different real-world multiplex networks, introducing
novel techniques for controlling inter-layer correlations of networks without
changing their structure, and taking advantage of synthetic network models with
tunable levels of inter-layer correlations
Embedding-aided network dismantling
Optimal percolation concerns the identification of the minimum-cost strategy for the destruction of any extensive connected components in a network. Solutions of such a dismantling problem are important for the design of optimal strategies of disease containment based either on immunization or social distancing. Depending on the specific variant of the problem considered, network dismantling is performed via the removal of nodes or edges, and different cost functions are associated to the removal of these microscopic elements. In this paper, we show that network representations in geometric space can be used to solve several variants of the network dismantling problem in a coherent fashion. Once a network is embedded, dismantling is implemented using intuitive geometric strategies. We demonstrate that the approach well suits both Euclidean and hyperbolic network embeddings. Our systematic analysis on synthetic and real networks demonstrates that the performance of embedding-aided techniques is comparable to, if not better than, the one of the best dismantling algorithms currently available on the market