Cooperative Dynamics Research Articles

Enhancing cooperative evolution in spatial public goods game by particle swarm optimization based on exploration and q-learning

In evolutionary game theory, the emergence and maintenance of cooperative behavior in a population often face challenges posed by the temptation of free-riding behavior, which offers high individual payoff. Recently, apart from a range of mechanisms that promote the formation of cooperation, individual learning abilities under limited information have emerged as a key factor in adjusting agents' strategies. This paper introduces q-learning and particle swarm optimization into the realm of evolutionary dynamics. The primary focus is on investigating the impact of Exploration-based Particle Swarm Optimization (EPSO) and Q-learning-based Particle Swarm Optimization (QPSO) on the evolution of cooperation in a continuous version of the spatial public goods game (SPGG) with punishment. EPSO defines a rule for updating agents' strategies based on individual and limited population information. It also integrates an exploration mechanism to increase the diversity and directionality of the strategies. Additionally, QPSO serves to adaptively optimize the parameters of EPSO, addressing the issue of parameter control limiting the EPSO's performance. Leveraging experiential learning and iterative adjustment, QPSO progressively refines system parameters, thus rationally assimilating knowledge and updating individual strategies to attain optimal payoff. Through extensive simulation studies, it has been observed that employing QPSO's adaptively optimized parameters in EPSO significantly promotes the cooperative evolution in the SPGG with punishment. Furthermore, individual learning coefficients, when too low or too high, both facilitate the occurrence of cooperation. Simultaneously, higher inertia weight coefficients strengthen the system's cooperation level, while lower punishment intensity coefficients and higher gain intensity coefficients effectively promote the cooperation emergence and exert a significant influence on the overall cooperation level of the system. This research provides a new perspective for designing real-world schemes that encourage cooperation and offers insights into the intricate dynamics of cooperation in complex systems.

Measuring the extreme linkages and time-frequency co-movements among artificial intelligence and clean energy indices

This is the first study analyzing the volatility connectedness and time-frequency interdependence between AI index and clean energy index. Specifically, we use the QVAR frequency connectedness, Wavelet Local Multiple Correlations (WLMC) and Granger causality quantile methods to check the risk spillovers and multivariate time and frequency relationships among the eight clean energy indexes and the AI index. This is over the period from December 18, 2017 to April 4, 2023. Our results show: (1) NASDAQ OMX Geothermal Index is the strongest net sender of short- and long-term shocks in the system during extreme upside market conditions. In downturn conditions, the S&P Global Clean Energy Index is the largest net shock sender. The AI Index exports shocks at all frequencies. In addition, market connectedness among markets is stronger under extreme market conditions. (2) We find that the AI Index predominantly exhibited positive co-movements with clean energy indices, primarily concentrated within the long-term frequency domain. However, they displayed robust cooperative dynamics across all frequency domains within the context of multivariate wavelet interconnections. (3) The quantile granger causality analysis revealed that below the extreme bullish threshold (0.95), the NASDAQ CTA Artificial Intelligence & Robotics index could predict changes in the risk associated with all clean energy indices. However, under extremely bullish quantile conditions, the NASDAQ CTA Artificial Intelligence & Robotics index statistically exhibited Granger causality only with respect to the NASDAQ OMX Renewable Energy Index, NASDAQ OMX Geothermal Index, and WilderHill Clean Energy Index.

The influence of molecular shape on reorientation dynamics of sizable glass-forming isomers at ambient and elevated pressure

We used dielectric spectroscopy to access the molecular dynamics of three isomers with a structure based on a sizable, partially rigid, and non-polar core connected to a polar phenylene unit differing in the position of the polar group, and, consequently, the direction and magnitude of the dipole moment to address the question how unique molecular properties, in particular large size and elongated shape, affect the dynamics. The position of the polar group differentiates the molecular shape and isomer’s anisotropy and leads to different thermal and dynamic properties of the isomers. The shape of permittivity loss spectra was governed by magnitudes of the longitudinal and transverse components of dipole moment to a large extent. For para isomer with negligible traverse component of dipole moment, the narrowest loss peak was found while for meta isomer, the bimodal loss peak was observed at high temperatures. Its shape evolved on cooling limiting the possibility of individual mode separation near glass transition where the dynamics were more cooperative. High-pressure dielectric studies showed that sizable isomers were characterized by the pronounced sensitivity of glass transition temperature, Tg, to compression. Observed high activation volumes, such as 735 cm3/mol at Tg for para isomer, were found to correlate with the length scale of dynamic cooperativity. The number of dynamically correlated molecules depended on molecular shape and varied among isomers while the determined values were much smaller than that reported for other glass-forming liquids. We discussed here the obtained results in the context of the specific properties of the systems studied showing the overriding role of anisotropy.

Coexistence and competition: Double attractors in hybrid mode-locked fiber lasers

The hybrid mode-locking technique has been widely used in enhancing pulse quality, but the specific mechanism of hybrid mode-locking remains unclear. In this work, we experimentally investigate three pulse formation mechanisms in saturable absorbers (SA) and nonlinear polarization evolution (NPE) passively hybrid mode-locked fiber laser, which are SA domination, NPE domination, and SA-NPE co-domination switching and clarified the existent dynamic competition and cooperation between the two mode-locking mechanisms of the hybrid mode-locked fiber laser. The method of simulating the filtered gain spectrum with customized filtering is proposed, and the switching of pulse formation mechanisms is numerically investigated using the coupled Ginzburg–Landau equations. The presence of a double attractor subsystem in a hybrid mode-locked fiber laser is proposed and demonstrated. Our results deepen the understanding of hybrid mode-locked fiber lasers and provide experimental ideas for the study of multi-attractor coexistence.

Cooperation dynamics in multiple correlated games: A review

Individuals often engage in complex, non-isolated interactive environments. The interdependence manifested by strategic interaction environments across multiple dimensions or attributes has advanced the recognition of correlated games. The behavioral choices in one strategic scenario can be influenced by strategic attempts in another. How the correlation between different strategic environments affects the cooperation dynamics has raised much attention recently. In this perspective, we overview the latest progress that accounts for such cross-reciprocity. Firstly, we focus on the cases where individuals consecutively interact in environments with varying payoff structures, the values of which depend on the behaviors present in the previous game. Secondly, we pay attention to how strategic interaction affects the dynamics in multi-issue games in which individuals simultaneously interact in different environments. It holds significant implications for further examining the evolution of behavior from the perspective of correlations between different scenarios. Finally, we come up with some potential directions and points for further research.

Policy Recommendation for Strengthening Capacity for Urban Disaster Management through Open and Distance Learning in Bangladesh

The adverse effects of climate change-induced geo-environmental changes have turned Bangladesh prone to intensifying recurring hazards like- floods, erratic rainfall, landslides, cyclones, storm surges, riverbank erosion, deforestation, droughts, and many more. Earthquake has also been identified as a hazard in Bangladesh. In addition, congested and unhealthy residential areas with high population density, inadequate infrastructural transport and communication facilities, and limited urban disaster management capabilities have been worsening the situation. The main theme of the study was to explore the ways of capacity building of disaster management in Dhaka City Corporation (DCC) through the Open and Distance Learning (ODL) approach offered by the School of Social Sciences, Humanities, and Languages (SSHL), Bangladesh Open University (BOU). The BOU has extensive access to communicate and spread knowledge to its large number of learners within the shortest possible time. Hence, the present research attempted to explore the prospects of the Open and Distance Learning (ODL) approach for strengthening the capacity of urban disaster management through BOU by forming skilled Urban Disaster Volunteer (UDV) teams in different parts of the DCC. Creating and incorporating an Urban Disaster Management (UDM) knowledge pool regarding the hazard and disaster modes, types, seasons, and patterns should be developed to strengthen the Urban Disaster Management Capacity (UDMC). A dynamic cooperation between the national policymakers and local stakeholders has to be accomplished to establish improved awareness through acquiring hazard and disaster-relevant knowledge, and the ability to cope with inevitable disasters.

КОГНІТИВНА БЕЗПЕКА ЯК ВИМІР РОСІЙСЬКО- УКРАЇНСЬКОЇ ВІЙНИ

Cognitive security is an important dimension of national and international security. It is urgent to specify the cognitive security dimension under the ongoing russian aggression against Ukraine. For the purpose of characterizing cognitive security as a dimension of the ongoing russia - Ukraine war, the author has utilized the method of case study. As a result, it can be stated that cognitive security is a crucial dimension of the ongoing russia - Ukraine war. Cognitive warfare is aimed at affecting human cognition, in particular, the ability to rationalize, think critically and make appropriate decisions. In a cognitive war the goal is to win hearts and minds of people. Therefore the goal of cognitive security is to ensure that people have developed resistance to harmful and malicious informational and psychological influences. As to the trends of cognitive security development, cognitive warfare is being widely used by various actors worldwide. Large-scale usage of cognitive warfare can lead to society-wide divisions in public opinion and stalling government institutions’ functioning. There are suggestions voiced as to adding the sixth warfighting domain — the cognitive domain — to the five ones (land, sea, air, space, and cyberspace) recognized by the NATO countries. It can be concluded that there are such characteristics of the cognitive warfare utilized in the russia-Ukraine war, as wide usage of disinformation and propaganda, malicious narratives and respective counternarratives aimed at domestic and international audiences. Ukraine actively counteracts russia’s negative cognitive influences by means of the government-adopted measures, grassroot activism and dynamic cooperation with partners and allies.

Dyadic inter-group cooperation in shotgun hunting activities in a Congo Basin village.

Understanding the dynamics of inter-group cooperation in human adaptation has been the subject of recent empirical and theoretical studies in evolutionary anthropology, beginning to fill gaps in our knowledge of how interactions across political, economic and social domains can - and often do - lead to stable, large-scale cooperation. Here we investigate dyadic intergroup cooperation in shotgun hunting in the Republic of the Congo. In the Congo Basin, inter-group cooperation between foragers and farmers is at the centre of an exchange system maintained by traditional norms and institutions such as fictive kinship. Here, we focused on what factors predict cooperative shotgun hunting exchanges between BaYaka and Yambe. We conducted structured interviews with 48 BaYaka hunters and 18 Yambe men who organise hunts in a village along the Motaba River. We used Bayesian multilevel regression models to investigate the influence of Yambe and BaYaka attributes on probability of dyadic cooperation. We found that BaYaka men's reputations as skilled hunters and their family size each predicted cooperation in shotgun hunting, whereas there was no effect of Yambe attributes (status, wealth, family size). We discuss the results in terms of evolutionary models of men as hunters and inter-group cooperation, as well as biodiversity conservation implications.

International Sustainable Supply Chain Management Under Bilateral Governments’ Policy Intervention and Power Asymmetry

This article aims to address the issue of international sustainable supply chain management under bilateral governments’ policy intervention. The dynamic and stochastic features of bilateral governments’ policy, focusing on collaboration and power asymmetry, are analytically considered. Specifically, various cross-governmental interaction factors, such as green investment efforts, interaction externalities, and political power asymmetry, are characterized and examined in the proposed theoretical model. Accordingly, a multimethodological approach using a two-stage game-theoretic analytical model is developed, where the decision dynamics of cross-governmental cooperation are investigated at the first stage, and its influence on sustainable supply chain management (in both countries) is explored at the second stage. Anecdotal evidence and applicability of the proposed model are illustrated via an empirical study using multiple-data sources. We show that governmental decisions for bilateral cooperation are significantly related to the bilateral interaction factors such as green investment efforts and less likely to be affected by the power asymmetry in the long run. Furthermore, we find that cooperative bilateral policy intervention favors not only the enhancement of bilateral social welfare (the government level) but also the sustainability of international supply chains (the firm level).

China’s Climate Diplomacy and Energy Security

As China continues to assert itself on the global stage, its energy policies are increasingly intertwined with its broaderGeopolitical ambitions. The country’s investments in renewable energy are not just about reducing carbon emissions;they also serve as a strategic tool for enhancing energy security and reducing dependency on foreign energy imports.Moreover, China’s approach to climate change diplomacy is shaping its relationships with other major powers, particularlythe United States, influencing the dynamics of international cooperation on environmental issues. While China’s progressin renewable energy is commendable, significant challenges remain, including the need to increase the domestic utilisationof renewable sources and afresh the logistical and infrastructural barriers that impede further development. Ultimately,China’s journey toward becoming a renewable energy superpower will be a critical factor in global effort to combat climateChange and redefine the future of international relations

Тенденции развития Евросоюза: некоторые аспекты экономической интеграции

The article is devoted to the analysis of the European Union development as an integration association. The economic aspects of integration within the EU as a whole as well as developing sub-integration processes are highlighted. Existing estimates show fluctuation in the level of the EU integration and its significant reduction in certain areas during some periods. The internationalization of the world economy and the increasing involvement of the EU in these processes couldn’t but have an impact on the intra-European situation. The assessment of the economic integration is made on the basis of the dynamics of the trade-investment cooperation and migration processes also. The analysis showed that different economic ties are not equally involved in the integration within the EU. If at the beginning of the XXI century the merchandise trade and FDI were comparable in terms of the level of involvement in the intra-European flows, then at present investment ties are considerably inferior to trade ones, having refocused on countries outside the EU. There is a steady trend in increasing of the share of citizens of non-EU countries living in the EU as well as EU citizens born in non-EU countries. The complexity of the European integration is traced by the example of sub-integration processes in the Visegrad Group. It is shown that accession to the EU has stimulated trade-investment cooperation within the “fourth”, but strong contrasts between members continue to persist. One of the main factors of the participation level in sub-integration is the economy size. Due to national features investment ties in terms of outstock are involved in subintegration processes more than trade ones. Sub-integration will continue to develop in the EU due to long-term factors, “complicating” pan-European integration processes, the non-linearity of which will remain.

АНАЛІЗ ЗОВНІШНЬОЇ ТОРГІВЛІ ТОВАРАМИ УКРАЇНИ З КРАЇНАМИ ЄВРОПЕЙСЬКОГО СОЮЗУ

The article is devoted to the study of foreign trade in goods of Ukraine with the countries of the European Union (hereinafter – the EU) with the identification of priority partners for the purpose of diversification and activation of foreign trade cooperation. It was emphasized that the foreign trade of Ukraine is dominated by trade in goods, where a negative trade balance is formed, in particular, in trade with EU countries. In order to determine the key consumers of domestic goods among the EU-27 countries, an ABC analysis was conducted based on the volume of goods exported to them by Ukraine in 2016–2021. The distribution of EU countries into groups was carried out as follows: group A – countries that account for a significant volume of exports of goods by Ukraine (about 80% of the total volume); group B – countries with an average level of export supplies of goods from Ukraine (about 15%); group C – countries with a small volume of exports of goods from Ukraine (about 5%). ABC-analysis is complemented by XYZ-analysis, which allows to analyze and forecast the stability of export of goods to EU countries. Based on the results of the ABC-XYZ analysis, a conclusion was made regarding the expediency of supporting the volume and dynamics of trade cooperation with key EU partner countries in the export of goods – Poland, Italy, Germany, the Netherlands, Spain, Romania, the Czech Republic, Hungary, Slovakia, Austria, and the need to intensify efforts to increasing the export of goods to countries that in the medium term have the potential to become attractive markets for the consumption of domestic products – France, Bulgaria, Belgium, Lithuania, and to a lesser extent – Denmark, Greece and Latvia. At the same time, it is noted that the vast majority of these countries are highly developed economies of the European Union, and trade in goods with them for Ukraine is disparate. Therefore, it is important to continue cooperation with the EU regarding the signing of the Agreement on Conformity Assessment and Acceptance of Industrial Products, recognition of the equivalence of sanitary and phytosanitary measures for opening markets, and simplifying the export of food and agricultural products. It is also necessary to increase efforts to gradually open public procurement markets. The further liberalization of transport with the EU, the conclusion of agreements in the field of road, inland water and railway transport are also important.

Chaos emergence and dissipation in a three-species food web model with intraguild predation and cooperative hunting

<abstract><p>We explore the dynamics of a three-species Lotka-Volterra model incorporating intraguild (IG) predation. The model encompasses interactions between a basal prey, intraguild prey and omnivorous top/intraguild predator. These interactions are characterized by linear functional responses, while considering intraspecific competition and cooperative hunting dynamics. The study involves a comprehensive stability of different steady states and bifurcation analysis. Bifurcation structures unveil shifts in equilibrium stability and the emergence of new equilibrium states. Investigation into dynamics around the coexistence equilibrium highlights diverse behaviors, including stable coexistence, oscillations and chaos. Furthermore, exploration of species' densities under parameter variations uncovers distinct patterns, ranging from stability to chaos. Incorporating the concept of hunting cooperation among IG predators and IG prey can lead to the emergence or suppression of chaotic oscillations, respectively. Additionally, we observe that lower consumption rate of IG predator and cooperation of IG predator helps the system to keep in a stable state position.</p></abstract>

Emergence of cooperative particle dynamics in quasi-two-dimensional glass-forming colloidal suspensions

As the concentration of particles in a glass-forming liquid increases, their dynamics slow down significantly, displaying solid-like behavior. This behavior is primarily attributed to cage formation, wherein particles are trapped by their neighbors. However, the particle dynamics near the onset of cage formation remain limitedly understood. In this study, we systematically investigated the dynamics of particles in a quasi-two-dimensional glass-forming colloidal suspension using a particle-level simulation. We utilized the “raspberry” model with a hybrid simulation approach. This approach combined lattice Boltzmann and molecular dynamics schemes for elucidating hydrodynamically interacting densely packed colloidal suspensions, with an area packing fraction of 0.45 ≤ ϕ ≤ 0.85. At a quiescent condition where particles underwent thermal motion, the string-like movements of particles became pronounced as ϕ increased. The hydrodynamic interactions between these particles were effective up to ϕ = 0.6, wherein the string-like motion first appeared, but were mostly screened at higher ϕ values. Furthermore, we extended our analysis by imposing a small probing force, locally applied to the suspensions. The most significant response occurred at ϕ = 0.6, where particles moved cooperatively during the cage formation process, similar to the experimental results of Li et al. [Nature 587, 225–229 (2020)]. By linking particle behaviors in two different scenarios, our study enhances our understanding of the emergence of highly cooperative particle movement and sheds light on the role of hydrodynamic interactions in glass-forming colloidal suspensions.

Impact of cooperative or competitive dynamics between the yeast Saccharomyces cerevisiae and lactobacilli on the immune response of the host.

Fungi and bacteria can be found coexisting in a wide variety of environments. The combination of their physical and molecular interactions can result in a broad range of outcomes for each partner, from competition to cooperative relationships. Most of these interactions can also be found in the human gastrointestinal tract. The gut microbiota is essential for humans, helping the assimilation of food components as well as the prevention of pathogen invasions through host immune system modulation and the production of beneficial metabolites such as short-chain fatty acids (SCFAs). Several factors, including changes in diet habits due to the progressive Westernization of the lifestyle, are linked to the onset of dysbiosis statuses that impair the correct balance of the gut environment. It is therefore crucial to explore the interactions between commensal and diet-derived microorganisms and their influence on host health. Investigating these interactions through co-cultures between human- and fermented food-derived lactobacilli and yeasts led us to understand how the strains' growth yield and their metabolic products rely on the nature and concentration of the species involved, producing either cooperative or competitive dynamics. Moreover, single cultures of yeasts and lactobacilli proved to be ideal candidates for developing immune-enhancing products, given their ability to induce trained immunity in blood-derived human monocytes in vitro. Conversely, co-cultures as well as mixtures of yeasts and lactobacilli have been shown to induce an anti-inflammatory response on the same immune cells in terms of cytokine profiles and activation surface markers, opening new possibilities in the design of probiotic and dietary therapies.

A Dynamic Event-Triggered Cooperative Method of Economic Operation for Integrated Energy Systems

A Dynamic Event-Triggered Cooperative Method of Economic Operation for Integrated Energy Systems

Cooperative dynamics of DNA-grafted magnetic nanoparticles optimize magnetic biosensing and coupling to DNA origami.

Magnetic nanoparticles (MNPs) provide new opportunities for enzyme-free biosensing of nucleic acid biomarkers and magnetic actuation by patterning on DNA origami, yet how the DNA grafting density affects their dynamics and accessibility remains poorly understood. Here, we performed surface functionalization of MNPs with single-stranded DNA (ssDNA) via click chemistry with a tunable grafting density, which enables the encapsulation of single MNPs inside a functional polymeric layer. We used several complementary methods to show that particle translational and rotational dynamics exhibit a sigmoidal dependence on the ssDNA grafting density. At low densities, ssDNA strands adopt a coiled conformation that results in minor alterations to particle dynamics, while at high densities, they organize into polymer brushes that collectively influence particle dynamics. Intermediate ssDNA densities, where the dynamics are most sensitive to changes, show the highest magnetic biosensing sensitivity for the detection of target nucleic acids. Finally, we demonstrate that MNPs with high ssDNA grafting densities are required to efficiently couple to DNA origami. Our results establish ssDNA grafting density as a critical parameter for the functionalization of MNPs for magnetic biosensing and functionalization of DNA nanostructures.

Obstacle Avoidance Control Strategy of Multi-robot Dynamic Cooperative Formation of Large-load-ratio Six-legged Robot under Nonholonomic Constraints

Obstacle Avoidance Control Strategy of Multi-robot Dynamic Cooperative Formation of Large-load-ratio Six-legged Robot under Nonholonomic Constraints

Similarity Caching in Dynamic Cooperative Edge Networks: An Adversarial Bandit Approach

Similarity Caching in Dynamic Cooperative Edge Networks: An Adversarial Bandit Approach

Sobre as dinâmicas de cooperação e/ou competição na Eurorregião Galiza-Norte de Portugal

At present, relations between Galicia and Portugal seem to be characterised by a certain paradox. On the one hand, since the 1990s, the EU has promoted territorial cooperation through financial contributions (INTERREG) for the implementation of joint projects. Later, it provided a legal-institutional framework through the regulation of European Groupings of Territorial Cooperation (EGTC). This cooperation, especially crossborder cooperation, is conceived as a useful tool for improving the competitiveness of certain local and regional areas (barrier effect) and for bringing citizens closer together. At the same time, in the context of globalisation and the internationalisation of markets, states are practising a “best place policy”. They try to create the most suitable conditions within their borders for attracting investment and capital appreciation. In this way, competitive dynamics are generated between territories. This article aim to carry out an analysis of the dynamics of competition and cooperation that can be detected in the Galicia-North Portugal Euroregion. To this end, we will analyse the discourse of the main actors and agents involved in the productive processes in the Euroregion: politicians, business leaders and trade unions.