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Among the properties describing the behavior of centrality measures with respect to network modifications, score monotonicity means that adding an arc increases the centrality score of the target of the arc; rank monotonicity means that adding an arc improves the importance of the target with respect to the remaining nodes. It is known (Boldi and Vigna Intern Math 10:222–262, 2014, Boldi et al. Netw Sci 5(4):529–550, 2017) that score and rank monotonicity hold in directed graphs for almost all the classical centrality measures. In undirected graphs one expects that the corresponding properties hold when adding a new edge—in this case, both endpoints of the new edge should enjoy the increase in score/rank. However, recent results (Boldi et al. in Netw Sci 11(3):1–23, 2023) have shown that this is not true: for many centrality measures, it is possible to find situations in which adding an edge reduces the rank of one of its two endpoints. In this paper we introduce a weaker property for undirected networks, semi-monotonicity, in which just one of the two endpoints of a new edge is required to enjoy score or rank monotonicity. We show that this property is satisfied by closeness centrality, by a large class of distance-based centralities, and (somehow surprisingly) by betweenness centrality. In the last two cases, we prove in fact a stronger property, basin dominance, which is of independent interest. [ABSTRACT FROM AUTHOR]

Egocentric networks represent a popular research design for network research. However, to what extent and under what conditions egocentric network centrality can serve as reasonable substitutes for their sociocentric counterparts are important questions to study. The answers to these questions are uncertain simply because of the large variety of networks. Hence, this paper aims to provide exploratory answers to these questions by analyzing both empirical and simulated data. Through analyses of various empirical networks (including some classic albeit small ones), this paper shows that egocentric betweenness approximates sociocentric betweenness quite well (the correlation is high across almost all the networks being examined) while egocentric closeness approximates sociocentric closeness only reasonably well (the correlation is a bit lower on average with a larger variance across networks). Simulations also confirm this finding. Analyses further show that egocentric approximations of betweenness and closeness seem to work well in different types of networks (as featured by network size, density, centralization, reciprocity, transitivity, and geodistance). Lastly, the paper briefly presents three ideas to help improve egocentric approximations of centrality measures. [ABSTRACT FROM AUTHOR]

Extrafloral nectaried plants and myrmecophytes offer resources to ants that engage in protective mutualisms. The role of different ant species in herbivore deterrence has long been analyzed by using insect baits, and ants are regarded as effective plant guards if they attack the insects. Here, by performing a literature review, we conducted a comparative investigation on which ants display aggression toward experimental prey, which ants are better plant guards, and which plants (extrafloral nectaried plants or myrmecophytes) are better defended by ants. Data revealed that studies evaluating ant aggression toward insect baits have been performed on 37 extrafloral nectaried plant species and 19 myrmecophytes, and have involved over 30 genera of ants. Extrafloral nectaried plants and myrmecophytes rely on specific ant fauna to defend them from herbivores. In extrafloral nectaried plants, Camponotus and Crematogaster were regarded as the best plant protectors, as they attacked insects in nearly all plants. In myrmecophytes, Azteca, Pheidole, and Pseudomyrmex were the most important insect attackers. Myrmecophytes were better protected by ants, as all insects were attacked; in extrafloral nectaried plants, some ants failed to attack the insects. Plants are patrolled by several different ants, but there is a core of ants that excel in protection, and this varies according to plant type (extrafloral nectaried plants and myrmecophytes). With this knowledge, it may be possible to label different ants as effective plant guards, to anticipate their effects on plant performance, and even to understand their potential role as biological control agents. [ABSTRACT FROM AUTHOR]

Reciprocity in the form of contingent exchanges of goods and services is widespread across animals. While there is ample evidence for helping to be contingent upon the help received from a partner, less attention has been paid to partner avoidance based on harm inflicted by a partner. Here, we investigated whether partner choice for agonistic support against powerful targets is guided by loyalty received, i.e., the tendency to refrain from attacking the subject in a coalition with any third partner. We further assessed whether loyalty received by all cooperation partners may generate increased levels of betweenness in the coalition network of a group, a measure of indirect connectedness that has previously been associated with fitness benefits. Based on observational data from male coalitions against male group mates in Barbary macaques (Macaca sylvanus), loyalty received was found to predict the frequency of cooperation in coalitions and the loyalty given to a partner. We propose that loyalty‐guided reciprocity will be favored in species with rank‐changing coalitions where defection is particularly risky. The more loyal a male's cooperation partners were, the more central he was in the coalition network in terms of higher in betweenness, suggesting a cognitively simple strategy underlying complex network positioning. Analyses of simulated data suggest strong correlations of loyalty and betweenness to be more prevalent in the relatively small groups characteristic of many primate species. [ABSTRACT FROM AUTHOR]

Physics thrives on precision, but paradoxes in set theory reveal limitations in our understanding of well-defined boundaries. Neutrosophic logic, challenging the excluded middle principle, introduces the concept of "betweenness" and partial belonging. This article explores among other things several possible avenues to resolve set theory paradoxism, including potential applications of neutrosophic logic in cosmology and particles, from set boundary, to the hypothetical "cosmosphere" boundary, to mixed fermion-boson condensate hypothesis. Embracing indeterminacy and fuzzy boundaries paves the way for a more holistic understanding of the universe's complexity.

An H -sequence of a vertex is defined by iteratively applying H -index to neighbors of the vertex in a graph. It is still not known whether changing the initial values affects the convergence of H -sequences. Our purpose is to investigate the properties of H -sequences initialized with arbitrary positive integers. This paper presents the necessary and sufficient conditions for the convergence of H -sequences. Theoretical results reveal the differences between divergent H -sequences of infinite graphs and finite graphs. Divergent H -sequences of infinite graphs are either periodic or non-periodic, whereas divergent H -sequences of finite graphs must be periodic with a period of 2. Based on H -sequences, we define 2-step coreness on the second-order neighbors of a vertex. A new centrality is proposed by combining classical coreness and 2-step coreness. The new centrality captures a wider range of information in a network. Experimental results show that the proposed centrality makes significant improvements over centralities such as betweenness, H -index and coreness. [ABSTRACT FROM AUTHOR]

Climate crises and other manifestations of environmental degradation are inextricably linked to the universalizing technoscientific paradigm underpinning capitalist industrialization and modernization. This study aimed to problematize the modern/colonial ontological dualism underpinning environmental crises and advocates the indigenous/Adivasi relational onto-epistemology. It offers a different reality that questions the virtues of science, capitalism, the colonial narrative, and its continuation in subjectivities and social relations with the modern state. Drawing from the new materialist insights of human and non-human imbrications and the framework of political ontology, this study further analyzed the Dongaria Kondh people's political success in defending their relational way of worlding against corporate-driven extractivism. The state perpetuates violence and takes development initiatives in this mineral-rich eastern Indian province. While other political movements have succumbed to combined corporate and state power, the Dongaria's political struggle continues in different forms. Finally, the article makes the point that knowledge and insights born out of political struggle against a particular ontology, masquerading as universal, press the need for engagement between different realities, knowledges, and recognition of a pluriverse, a world of multiple ways of worlding, where each ontological story exists not as superior or inferior, but as equal, with space for mutual engagement and dialogue.

Christopher Alexander famously declared that “a city is not a tree,” while Leslie Martin declared that “the grid is [a] generator.” This article investigates how Alexander’s call for overlap, adaptability, and order can indeed be manifested in grid networks, as Martin claimed. Order has been measured using the entropy of street orientation, while adaptability has been denoted by the streets’ betweenness values. Through the analysis of Abu Dhabi’s neighborhoods and global urban areas, the study reveals that overlap, order, and adaptability can coexist in gridded street network. A fine-grain scale of the grid plays a critical role in supporting the quality of urban space. To foster adaptation, planning policies should focus on adaptability providing room for informal and spontaneous growth. We conclude by noting that this approach represents a reconciliation between Christopher Alexander’s views and those of Leslie Martin.

The vulnerability of the Amazon has widely increased with the COVID-19 global pandemic and with the dismantlement of environmental protection policies in Brazil during the Bolsonaro administration. By contrast, local initiatives focusing on sustainable production, conservation, enhancing local people's quality of life, and supporting a more inclusive economy have emerged throughout the region and are building resilience in face of these disruptions. They represent seeds for transformation towards more sustainable trajectories from the ground up. In this context, women play a significant role, but their actions and voices are poorly understood, studied, or even considered. In this article, we use a novel approach to engage and highlight women's experiences by connecting decolonial and process-relational perspectives. Decolonial and process-relational thinking are closely linked in many ways, including in that they embrace difference as a mode of experiencing social-ecological relations. One particular aspect of this link is the shared focus on liminal thinking or thinking from the borders, what we call 'betweenness'. In our decolonial praxis, we highlight women's perspectives on their particular and diverse ways of life in the Amazon as they confront diverse pressures. To this end, we collaborated with 39 women from Santarém and neighboring towns in western Pará through participant observation, semi-structured interviews and facilitated dialogues. We discuss their perspectives on regional transformation, particularly the expansion of large-scale agribusiness around rural communities, and their understanding and responses to these changes. We reflect on the mutual learning experience resulting from the transdisciplinary engagement between researchers and collaborators. [ABSTRACT FROM AUTHOR]

Transit functions are introduced to study betweenness, intervals and convexity in an axiomatic setup on graphs and other discrete structures. Prime example of a transit function on graphs is the well studied interval function of a connected graph. In this paper, we study the Cycle transit function C(u; v) on graphs which is a transit function derived from the interval function. We study the betweenness properties and also characterize graphs in which the cycle transit function coincides with the interval function. We also characterize graphs where ... as an analogue of median graphs. [ABSTRACT FROM AUTHOR]

The growing use of gas-fired power generators and electricity-driven gas compressors and storage has increased the interdependence between electric power infrastructure and natural gas infrastructure. However, the increasing interdependence may spread the failures from one system to the other, causing subsequent failures in an integrated power and gas system (IPGS). This paper investigates the structural vulnerability of a realistic IPGS based on complex network theory. Different from the existing works with a focus on the static vulnerability analysis for an IPGS, this paper considers both static and dynamic vulnerability analysis. The former focuses on vulnerability analysis under random and selective failures without flow redistribution, while the latter concentrates on vulnerability analysis under cascading failures caused by flow redistribution. Also, different from the existing works with a focus on the IPGS as a whole, we not only analyze the vulnerability of the IPGS but also analyze the vulnerability of the power subsystem (PS) and gas subsystem (GS), in order to understand how the vulnerability of the IPGS is affected by its PS and GS. The analysis results show that (1) if the PS and GS are more susceptible to cascading failures than selective and random failures, the IPGS as a whole is also more vulnerable to cascading failures. (2) There are different dominant factors affecting the IPGS vulnerability under cascading failures and selective failures. Under cascading failures, the GS has a more significant impact on the IPGS vulnerability; under selective failures, the PS has a more important impact on the IPGS vulnerability. (3) The IPGS is more vulnerable to failures on the critical nodes, which are identified from the IPGS as a whole rather than from the individual PS or GS. The results provide insights into the design and planning of IPGSs to improve their overall reliability. [ABSTRACT FROM AUTHOR]

Let H be a complete r-uniform hypergraph such that two vertices are marked in each edge as its 'boundary' vertices. A linear ordering of the vertex set of H is called an agreeing linear order, provided all vertices of each edge of H lie between its two boundary vertices. We prove the following Helly-type theorem: if there is an agreeing linear order on the vertex set of every subhypergraph of H with at most 2r − 2 vertices, then there is an agreeing linear order on the vertex set of H. We also show that the constant 2r − 2 cannot be reduced in the theorem. The case r = 3 of the theorem has particular interest in the axiomatic theory of betweenness. Similar results are obtained for further r-uniform hypergraphs (r ≥ 3), where one or two vertices are marked in each edge, and the linear orders need to satisfy various rules of agreement. In one of the cases we prove that no such Helly-type statement holds. [ABSTRACT FROM AUTHOR]

AbstractStress is a centrality measure determined by the shortest paths passing through the given vertex. Noting that adjacency matrix playing an important role in finding the distance and the number of shortest paths between given pair of vertices, an interesting expression and also an algorithm are presented to find stress using adjacency matrix. The results and algorithm are suitably adopted to obtain betweenness centrality measure. Further results are extended to the cases of Cartesian product [Formula: see text] of graphs, corona graph [Formula: see text] and their special cases.

ABSTRACTThe vulnerability of the Amazon has widely increased with the COVID-19 global pandemic and with the dismantlement of environmental protection policies in Brazil during the Bolsonaro administration. By contrast, local initiatives focusing on sustainable production, conservation, enhancing local people’s quality of life, and supporting a more inclusive economy have emerged throughout the region and are building resilience in face of these disruptions. They represent seeds for transformation towards more sustainable trajectories from the ground up. In this context, women play a significant role, but their actions and voices are poorly understood, studied, or even considered. In this article, we use a novel approach to engage and highlight women’s experiences by connecting decolonial and process-relational perspectives. Decolonial and process-relational thinking are closely linked in many ways, including in that they embrace difference as a mode of experiencing social-ecological relations. One particular aspect of this link is the shared focus on liminal thinking or thinking from the borders, what we call ‘betweenness’. In our decolonial praxis, we highlight women’s perspectives on their particular and diverse ways of life in the Amazon as they confront diverse pressures. To this end, we collaborated with 39 women from Santarém and neighboring towns in western Pará through participant observation, semi-structured interviews and facilitated dialogues. We discuss their perspectives on regional transformation, particularly the expansion of large-scale agribusiness around rural communities, and their understanding and responses to these changes. We reflect on the mutual learning experience resulting from the transdisciplinary engagement between researchers and collaborators.

Equity is one of the fundamental principles in the planning of public service facilities. In recent years, many cities have started to promote the construction of 15 min community living circles with the aim of providing residents with more equitable access to basic public services. Based on this background, this study explores an equity-oriented spatial quantitative analysis method to assist in the planning of public service facility layouts. The node centrality measurement index, such as betweenness from spatial syntax and social network analysis is introduced into the analysis method in order to consider the potential activity paths and flows of people at the community scale. Selecting the central city of Shanghai as a case study, the research presents results regarding spatial equity based on the relationship between public service demand and public service facilities supply. Building on this foundation, various approaches to enhancing equity are discussed: (1) optimizing the layout of public service facilities; (2) optimizing residential spatial patterns; and (3) optimizing pedestrian transportation networks. [ABSTRACT FROM AUTHOR]

In appreciating paintings, what we experience is either a result of their medium or object, regardless of whether the object is an actual thing, a fictional thing, an internal emotion, an abstract idea, or something else. However, the conceptions of 'betweenness' in traditional Chinese aesthetics and 'twofoldness' in contemporary Western aesthetics tell us that our experience of paintings might not be simply from the object or the medium itself but rather from a relation between the two. This study considers the intercultural value of the above concepts while examining how our aesthetic pleasure might derive from awareness of the object, the medium, and the play of our mind and body. [ABSTRACT FROM AUTHOR]

We present a generalised complex contagion model for describing behaviour and opinion spreading on social networks. Recurrent interactions between adjacent nodes and circular influence in loops in the network structure enable the modelling of influence spreading on the network scale. We have presented details of the model in our earlier studies. Here, we focus on the interpretation of the model and discuss its features by using conventional concepts in the literature. In addition, we discuss how the model can be extended to account for specific social phenomena in social networks. We demonstrate the differences between the results of our model and a simple contagion model. Results are provided for a small social network and a larger collaboration network. As an application of the model, we present a method for profiling individuals based on their out-centrality, in-centrality, and betweenness values in the social network structure. These measures have been defined consistently with our spreading model based on an influence spreading matrix. The influence spreading matrix captures the directed spreading probabilities between all node pairs in the network structure. Our results show that recurrent and circular influence has considerable effects on node centrality values and spreading probabilities in the network structure. [ABSTRACT FROM AUTHOR]

It is a classic result that a set of n non-collinear points in the Euclidean plane defines at least n different lines. Chen and Chvátal conjectured in 2008 that the same results is true in metric spaces for an adequate definition of line. More recently, this conjecture was studied in the context of quasi-metric spaces. One way to study lines in an space is though its betweenness. Given a quasi-metric space (V,ρ), its induced quasi-metric be-tweenness is the set of triples (x, y, z) ϵ V3 such that ρ(x, z) = ρ(x, y) +ρ(y, z). In this work, we prove the existence of a quasi-metric space on four points a, b, c and d whose quasi-metric betweenness is ẞ = {(c, a, b), (a, b, c), (d, b, a), (b, a, d)}. This space has only three lines, none of which has four points. Moreover, we show that the betweenness of any quasi-metric space on four points with this property is isomorphic to B. Since B is not metric, we conclude that Chen and Chvatal's conjecture is valid for any metric space on four points. [ABSTRACT FROM AUTHOR]

With the continuous development of smart grid technology, the scientific and accurate evaluation of smart grid with high reliability is required. The failure of important nodes in the smart grid will lead to large-scale power outages, so the evaluation of the important nodes in the smart grid is an important manifestation of evaluating the reliability of the smart grid. In this study, different dynamic and static comprehensive indicators such as local environment, global attribute, network topology and load level of nodes are studied. These comprehensive indicator models are used to evaluate the importance of nodes in smart grid. Finally, the TOPSIS method is adopted to combine dynamic and static indicators to evaluate the importance of smart grid nodes, and the IEEE-30 nodes are simulated and verified. The results show that the importance of node 6 is relatively high, which should be protected. [ABSTRACT FROM AUTHOR]

Sustainable urban form research brought with it a renewed interest in neighborhood planning units (NPUs). While there is some insightful historical and qualitative research on the location of nonresidential uses in NPUs, quantitative analysis of the accessibility of nonresidential uses in NPUs has received minimal attention. This article uses Multiple Centrality Assessment to understand the accessibility of nonresidential land uses in NPUs designs. Using NPUs in Abu Dhabi as a case study, the paper analyzes different patterns of street networks across different scales and proposes new concepts and models for understanding accessibility. A framework for accessible NPUs focuses on three elements: street layout design, permeability, and edge attractiveness. Permeability is defined by high levels of Gravity and/or Betweenness at an NPU's center at a global scale. On the other hand, the edge attractiveness that provides strong "seams" between NPUs is defined by high values of Gravity and/or Betweenness at an NPU's edges and perimeter locations at a global scale. Findings suggest that a well-designed NPU must be characterized by both permeability and edge attractiveness. Results also indicate that nonresidential areas should be located according to their functions and level of intensity. Findings stress that at a local scale, NPUs should be designed to have high accessibility and low permeability for daily nonresidential facilities at the center. However, to promote the interconnection between adjacent NPUs, the street networks should have high accessibility and high edge attractiveness for nonresidential facilities located along the edges at a global scale. This research presents a conceptual approach and practical implications for planning NPUs' nonresidential land uses and it contributes to the debate and practice on accessibility in an NPU. [ABSTRACT FROM AUTHOR]

The centrality of stations is one of the most important issues in urban transit systems. The central stations of such networks have often been identified using network to-pological centrality measures. In real networks, passenger flows arise from an interplay between the dynamics of the individual person movements and the underlying physical structure. In this paper, we apply a two-layered model to identify the most central stations in the Beijing Subway System, in which the lower layer is the physical infrastruc-ture and the upper layer represents the passenger flows. We compare various centrality indicators such as degree, strength and betweenness centrality for the two-layered model. To represent the influence of exogenous factors of stations on the subway system, we reference the al-pha centrality. The results show that the central stations in the geographic system in terms of the betweenness are not consistent with the central stations in the network of the flows in terms of the alpha centrality. We clarify this difference by comparing the two centrality measures with the real load, indicating that the alpha centrality approx-imates the real load better than the betweenness, as it can capture the direction and volume of the flows along links and the flows into and out of the systems. The empirical findings can give us some useful insights into the node cen-trality of subway systems.

This paper shows that in some axioms regarding the mixture of random variables, the requirement that the conclusions hold for all values of the mixture parameter can be weakened by requiring the existence of only one nontrivial value of the parameter, which need not be fixed. This is the case for the independence, betweenness, and mixture symmetry axioms. Unlike the standard axioms, these weaker versions cannot be refuted by experimental methods. [ABSTRACT FROM AUTHOR]

The ontology of artworks tells us that a work of art, for example, a painting, cannot be identified as either physical or mental object. By the same token, this paper argues the working of art or artistic labor cannot be identified as either physical or mental labor. However, the works and workings of art are regarded as either physical or mental in the prevailing aesthetic theory. The main reason is that classical Western metaphysics is bifurcated. However, traditional Chinese division of ontological categories is not a bifurcation but a trifurcation, which consists of dao道, xiang象, and qi器. This tripartite distinction avoids substantivism, while at the same time providing a framework that encompasses both the objective and the subjective face of the art work, by means of a dynamic exchange between the two poles. This paper shifts our perspective from classical Western metaphysics to traditional Chinese metaphysics and sets up a dialogue between Chinese and Western aesthetics. The ontological status of works and workings of art is neither physical nor mental, but the “betweenness” of the two.

Mercury (Hg) can accumulate in the food chain, posing significant threats to human health and biodiversity. Existing studies have identified critical primary suppliers, producers, and final consumers driving Hg emissions in global supply chains. However, the hotspots in the intermediate transmission stages of global supply chains remain unknown. This study reveals critical transmission sectors and transactions of global embodied Hg emissions during 1995–2022. Results show that the critical transmission sectors and transactions of global embodied Hg emissions have been moving from developed (e.g., Japan and Russia) to developing (e.g., China and India) economies. Critical transmission sectors were primarily concentrated in the metal products, transportation, machinery and equipment manufacturing, and construction industries. Domestic transactions were the primary transmission pathways for embodied Hg emissions, with nearly half of these being intra-sectoral transactions. These findings can help policymakers develop transmission-bound Hg reduction policies and multi-level cooperation to support joint Hg emission reduction. • Transmission hotspots of embodied Hg emissions in global supply chains are revealed. • Transmission hotspots have been moving from developed to developing economies. • Transmission-bound policies can help further reduce global Hg emissions. • Propose a multi-level cooperation framework to promote joint emission reduction. [ABSTRACT FROM AUTHOR]

• We explored network analyses, particularly centrality measures, as frequently applied to migratory networks of animals. • Centrality measures were developed to evaluate social interactions, not migration, and commonly used measures assume system properties that can make them biologically inappropriate for migration assessments. • Misinterpretations of network measures include, for example, (1) assuming nodes with the highest degree centrality are locations where individuals intermingle, and (2) that a high betweenness score identifies a node that is an important site along a main migratory route, among other issues. • Finally, jargon can result in ambiguous or conflicting messages; for example, the same network can be referred to as disconnected in graph theory, but as completely connected in the migratory connectivity literature. • New measures need to be developed specifically with animal migration applications in mind, and we provide a guide for researchers of animal movement for development and documentation. Network analysis is becoming a popular tool for the study of animal movement. Proliferation of software enables researchers to use network measures without reflecting on the underlying mathematics and biology. One common use characterizing movement networks, such as migration, with centrality measures. Predominantly developed to evaluate social systems, these measures now appear in applications across disciplines that vary greatly in system properties. Each network measure has a very specific mathematical definition, with implicit assumptions about system properties to which they are applied that often make them inappropriate for migration. We report mismatches between mathematical assumptions and applications of network measures to migration, primarily with bird examples. For example, of 11 trajectory-transmission network-flow processes observed in the real world, only two are applicable to bird migration, neither of which allows valid application of classical centrality measures. We also identify misinterpretations of network measures, such as nodes with the highest degree centrality as locations where individuals intermingle. Other misinterpretations include that a high betweenness score translates to a node that is frequently used or is an important site along a main migratory route. Finally, networks are used in different ways, ranging from descriptive visualization to quantitative prediction and we identify common cases, such as migratory connectivity, where this leads to miscommunication. Network-theoretic approaches to answer ecological research and conservation questions associated with migration are numerous, but new measures need to be developed for animal migration. We provide a guide for researchers of animal movement for measure selection, development, and documentation. [ABSTRACT FROM AUTHOR]

The growing use of gas-fired power generators and electricity-driven gas compressors and storage has increased the interdependence between electric power infrastructure and natural gas infrastructure. However, the increasing interdependence may spread the failures from one system to the other, causing subsequent failures in an integrated power and gas system (IPGS). This paper investigates the structural vulnerability of a realistic IPGS based on complex network theory. Different from the existing works with a focus on the static vulnerability analysis for an IPGS, this paper considers both static and dynamic vulnerability analysis. The former focuses on vulnerability analysis under random and selective failures without flow redistribution, while the latter concentrates on vulnerability analysis under cascading failures caused by flow redistribution. Also, different from the existing works with a focus on the IPGS as a whole, we not only analyze the vulnerability of the IPGS but also analyze the vulnerability of the power subsystem (PS) and gas subsystem (GS), in order to understand how the vulnerability of the IPGS is affected by its PS and GS. The analysis results show that (1) if the PS and GS are more susceptible to cascading failures than selective and random failures, the IPGS as a whole is also more vulnerable to cascading failures. (2) There are different dominant factors affecting the IPGS vulnerability under cascading failures and selective failures. Under cascading failures, the GS has a more significant impact on the IPGS vulnerability; under selective failures, the PS has a more important impact on the IPGS vulnerability. (3) The IPGS is more vulnerable to failures on the critical nodes, which are identified from the IPGS as a whole rather than from the individual PS or GS. The results provide insights into the design and planning of IPGSs to improve their overall reliability.

The idea that quantum effects could be harnessed to allow faster computation was first proposed by Feynman. As of 2020 we appear to have achieved ‘quantum supremacy’, that is, a quantum computer that performs a given task faster than its classical counterpart. This paper examines some possibilities opened up by potential future application of quantum computing to transportation simulation and planning. To date, no such research was found to exist, therefore we begin with an introduction to quantum computing for the programmers of transport models. We discuss existing quantum computing research relevant to transportation, finding developments in network analysis, shortest path computation, multi-objective routing, optimization and calibration – of which the latter three appear to offer the greater promise in future research. Two examples are developed in greater detail, (1) an application of Grover’s quantum algorithm for extracting the mean, which has general applicability towards summarizing distributions which are expensive to compute classically, is applied to an assignment or betweenness model - quantum speedup is elusive in the general case but achievable when trading speed for accuracy for limited outputs; (2) quantum optimization is applied to an activity-based model, giving a theoretically quadratic speedup. Recent developments notwithstanding, implementation of quantum transportation algorithms will for the foreseeable future remain a challenge due to space overheads imposed by the requirement for reversible computation. [ABSTRACT FROM AUTHOR]

As a basic platform for large-capacity, long-distance and high-reliability information transmission, the optical fiber backbone network may be destroyed by natural disasters or deliberately attacked. This may make the originally connected network topology be divided, or even the entire network be paralyzed, resulting in serious economic and social losses. How to establish the survivability model of the optical fiber backbone network and measure its survivability has become a key research problem to improve the robustness of the optical fiber backbone network. Based on the theory of complex network, this paper analyses the changing characteristics of network node degree and betweenness of optical backbone network under several typical network attack strategies. By establishing the survivability model of optical backbone network and analyzing the model, the changes of network performance in the face of typical network attacks are obtained.The optical fiber backbone network is more robust and invulnerable during the random attacks, and has certain characteristics of random networks. In the face of selective attacks, the network performance of the optical fiber backbone network decreases rapidly, and the network is relatively fragile. There is a threshold for the betweenness. When the attack does not exceed the threshold, the network betweenness will increase. After exceeding the threshold, the centrality and the network performance will decline sharply. [ABSTRACT FROM AUTHOR]

Influence maximization in social networks is defined as determining a subset of seed nodes where triggering the influence diffusion through the social network leads to the maximum number of final influenced nodes. The tradeoff between the runtime efficiency and effectiveness in the quality of response is the main issue in presenting solutions for this NP-hard optimization problem. Centrality-based methods are applied as a category of efficient heuristic-based solutions to this problem. The two leading causes of losing effectiveness in centrality-based methods are 1) only the link structure and non-awareness of influence diffusion are considered in determining the importance of nodes, and 2) influence overlap exists among selected seed nodes. To address the first cause, an influence-aware betweenness centrality measure is proposed considering both IC and LT models. Moreover, an existing influence-aware closeness centrality measure for LT model is adopted to cover both LT and IC models. To address the second cause, a greedy-based method is proposed by applying influence-aware centrality measures to identify the influential nodes, next to proposing a Jacquard-based measure to overcome the influence overlap problem. The experiments consist of two parts where two real-world datasets are applied: 1) the proposed influence-aware centrality measures are compared with their original versions, and 2) the greedy-based method is compared with benchmark methods. The results indicate the effectiveness of the influence-aware centrality measures and the proposed greedy-based method in maximizing the influence spread in social networks. [ABSTRACT FROM AUTHOR]

This study analyses the structural changes in European stock market indices using a minimal spanning tree and a Markov-switching model that examines the regime-changes in betweenness and closeness in addition to topological changes. The authors aim is to highlight the similarities and differences of previous recessions, namely the subprime mortgage crisis of 2008, the European sovereign debt crisis of 2010, and the recent period of Covid-19. Focusing on the structural changes in the graph, the appearance of a central index transmitting shocks is sought. The results show that there is a constant change in the stock market network, where stock market indices are linked to each other mainly through a central index in turbulent periods, while relationships become more diversified in calm periods. [ABSTRACT FROM AUTHOR]

Community is the foundation of modern cities, where urban residents spend most of their lifetime. Effective and healthy community design plays a vital role in improving residents' living quality. Pedestrian network is an indispensable element in the community. Successful pedestrian network design can help the residents be healthy both physically and mentally, build the awareness of "Go Green" for the society, and finally contribute to low-carbon and green cities. This paper proposes a community pedestrian network design method based on Urban Network Analysis with the help of the Rhino software. A case study of a typical community in Guangzhou, China was implemented, specifying the steps of the proposed method. The findings presented include the features of the citizens and the accessibilities of the neighbors that are obtained from the community pedestrian network simulation. The limitation and scalability of this method was discussed. The proposed method can be essential to designing healthy and sustainable communities. [ABSTRACT FROM AUTHOR]

Aim: Understanding the spatial ecology of animal movements is a critical element in conserving long‐lived, highly mobile marine species. Analyzing networks developed from movements of six sea turtle species reveals marine connectivity and can help prioritize conservation efforts. Location: Global. Methods: We collated telemetry data from 1235 individuals and reviewed the literature to determine our dataset's representativeness. We used the telemetry data to develop spatial networks at different scales to examine areas, connections, and their geographic arrangement. We used graph theory metrics to compare networks across regions and species and to identify the role of important areas and connections. Results: Relevant literature and citations for data used in this study had very little overlap. Network analysis showed that sampling effort influenced network structure, and the arrangement of areas and connections for most networks was complex. However, important areas and connections identified by graph theory metrics can be different than areas of high data density. For the global network, marine regions in the Mediterranean had high closeness, while links with high betweenness among marine regions in the South Atlantic were critical for maintaining connectivity. Comparisons among species‐specific networks showed that functional connectivity was related to movement ecology, resulting in networks composed of different areas and links. Main conclusions: Network analysis identified the structure and functional connectivity of the sea turtles in our sample at multiple scales. These network characteristics could help guide the coordination of management strategies for wide‐ranging animals throughout their geographic extent. Most networks had complex structures that can contribute to greater robustness but may be more difficult to manage changes when compared to simpler forms. Area‐based conservation measures would benefit sea turtle populations when directed toward areas with high closeness dominating network function. Promoting seascape connectivity of links with high betweenness would decrease network vulnerability. [ABSTRACT FROM AUTHOR]