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The interplay of cultural intolerance and action-assortativity for the emergence of cooperation and homophily
Full text linkThis paper investigates the emergence of cooperation in a heterogeneous population that is divided into two cultural groups. Agents are randomly matched in pairs to engage in a prisoner dilemma. The matching process is assortative in actions, that is, cooperators are more likely to be matched with cooperators, defectors are more likely to be matched with defectors. Agents exhibit a form of cultural intolerance: when two agents of different cultures are matched, they suffer a cost due to their cultural differences. We find that when cultural intolerance is sufficiently strong, homophily emerges together with perfect correlation between culture and behavior: all agents from one cultural group cooperate, while all agents from the other cultural group defect, and interactions among agents within the same cultural group are more frequent. The relation between cultural intolerance and societal welfare is non-monotonic. In particular, stronger cultural intolerance can increase cooperation when action-assortativity is weak, while it can increase defection when action-assortativity is strong. Moreover, everyone cooperating does not necessarily maximize total welfare unless cultural intolerance can be made sufficiently weak
Long-term EVA degradation simulation: Climatic zones comparison and possible revision of accelerated tests
No full textThe increasing demand of photovoltaics installations, also in harsh climatic conditions, requires the accurate comprehension of module lifetime and durability. Accelerated environmental tests (damp heat, thermal cycling, and humidity freeze) are performed as pass/fail criteria to determine whether modules are suitable for sale, while do not accurate predict durability in all possible climates. Recently, we proposed a computational model to study the thermo-oxidative degradation of EVA encapsulant. This model was suitable to describe effects of temperature fluctuations on degradation, while neglecting dramatic changes of outdoor exposure in different climatic zones. To investigate the correlation between climatic zones and EVA degradation, we completed the existing degradation model by adding the UV exposure dependency. This model, for the first time, simulates EVA thermo-photo-oxidation in accelerated and environmental conditions. We compared results of simulated standard accelerated tests and outdoor exposure, observing a significant mismatch of results. The low prediction capability of standard tests pushed us to analyze modified accelerated tests, by adding an internal UV source. Modified test simulations show a better matching with outdoor long-term weathering. The modified setup will enable novel accelerated tests with predictive behavior of long-term EVA degradation and a more accurate PV module lifetime
The Global Health Networks: A Comparative Analysis of Tuberculosis, Malaria and Pneumonia Using Social Media Data
Full text linkGlobal health networks (GHNs) of organizations fighting major health threats
represent a useful strategy to respond to the challenge of mobilizing and coordinating
different types of health organizations across borders toward a common goal.
In this paper we reconstruct the GHNs of malaria, tuberculosis and pneumonia by
creating a new unique database of health organizations from the official Twitter accounts
of each organization. We use a majority voter Multi Naive Bayes classifier to
discover, among the Twitter users, the ones that represent organizations or groups active
in each disease area. We perform a social network analysis (SNA) of the global
health networks (GHNs) to evaluate the structure of the network and the role and
performance of the organizations in each network. We find evidence that the GHN
of malaria, TBC and pneumonia are different in terms of performance and leadership,
geographical coverage as well as Twitter popularity. Our analysis validate the
use of social media to analyze GHNs, their effectiveness and to mobilize the global
community toward global sustainable development
A Complex Network Approach for the Estimation of the Energy Demand of Electric Mobility
Full text linkWe study how renewable energy impacts regional infrastructures considering the full deployment of electric mobility at that scale. We use the Sardinia Island in Italy as a paradigmatic case study of a semi-closed system both by energy and mobility point of view. Human mobility patterns are estimated by means of census data listing the mobility dynamics of about 700,000 vehicles, the energy demand is estimated by modeling the charging behavior of electric vehicle owners. Here we show that current renewable energy production of Sardinia is able to sustain the commuter mobility even in the theoretical case of a full switch from internal combustion vehicles to electric ones. Centrality measures from network theory on the reconstructed network of commuter trips allows to identify the most important areas (hubs) involved in regional mobility. The analysis of the expected energy flows reveals long-range effects on infrastructures outside metropolitan areas and points out that the most relevant unbalances are caused by spatial segregation between production and consumption areas. Finally, results suggest the adoption of planning actions supporting the installation of renewable energy plants in areas mostly involved by the commuting mobility, avoiding spatial segregation between consumption and generation areas
Inkjet printed 2D-crystal based strain gauges on paper
Full text linkWe present an investigation of inkjet printed strain gauges based on two-dimensional (2D) materials. The technology leverages water-based and biocompatible inks to fabricate strain measurement devices on flexible substrates such as paper. We demonstrate that the device performance and sensitivity are strongly dependent on the printing parameter (i.e., drop-spacing, number of printing passes, etc.). We show that values of the Gauge Factor up to 125 can be obtained, with large sensitivity (>20) even when small strains (0.3) are applied. Furthermore, we provide preliminary examples of heterostructure-based strain sensors, enabled by the inkjet printing technology
A 3D finite strain model for intralayer and interlayer crack simulation coupling the phase field approach and cohesive zone model
No full textIn this study, a new 3D finite element formulation which enables simulating the interaction between brittle crack propagation and interface delamination in heterogeneous materials is presented. The Phase Field (PF) model for brittle fracture has been coupled with the Cohesive Zone Model (CZM) within the framework of the large deformation analysis. These numerical techniques have been implemented within a 8-node locking-free solid shell element, relying on the enhanced assumed strain concept, and a 8-node interface finite element, respectively. The predictive capabilities of the proposed formulation have been assessed through the simulation of cracking in flat and curved geometries under in-plane and out-ofplane loading conditions. The results show the ability of the model to predict complex crack paths where intralayer crack propagation and delamination occur simultaneously and interact. The proposed formulation provides a powerful modeling tool for the simulation of fracture phenomena in heterogeneous materials and laminate structures, which are characterized by the existence of numerous interfaces, such as in photovoltaic laminates
Evidence for Mixed Rationalities in Preference Formation
Full text linkUnderstanding the mechanisms underlying the formation of cultural traits is an open challenge. This is intimately connected to
cultural dynamics, which has been the focus of a variety of quantitative models. Recent studies have emphasized the importance of
connecting thosemodels to empirically accessible snapshots of cultural dynamics. In particular, it has been suggested that empirical
cultural states, which differ systematically from randomized counterparts, exhibit properties that are universally present. Hence, a
question about the mechanism responsible for the observed patterns naturally arises. This study proposes a stochastic structural
model for generating cultural states that retain those robust empirical properties. One ingredient of the model assumes that every
individual’s set of traits is partly dictated by one of several universal “rationalities,” informally postulated by several social science
theories.The second, new ingredient assumes that, apart from a dominant rationality, each individual also has a certain exposure
to the other rationalities. It is shown that both ingredients are required for reproducing the empirical regularities. This suggests
that the effects of cultural dynamics in the real world can be described as an interplay of multiple, mixing rationalities, providing
indirect evidence for the class of social science theories postulating such a mixing
Transfer of Audio-Visual Temporal Training to Temporal and Spatial Audio-Visual Tasks
No full textTemporal and spatial characteristics of sensory inputs are fundamental to multisensory integration because they provide probabilistic information as to whether or not multiple sensory inputs belong to the same event. The multisensory temporal binding window defines the time range within which two stimuli of different sensory modalities are merged into one percept and has been shown to depend on training. The aim of the present study was to evaluate the role of the training procedure for improving multisensory temporal discrimination and to test for a possible transfer of training to other multisensory tasks. Participants were trained over five sessions in a two-alternative forced-choice simultaneity judgment task. The task difficulty of each trial was either at each participant’s threshold (adaptive group) or randomly chosen (control group). A possible transfer of improved multisensory temporal discrimination on multisensory binding was tested with a redundant signal paradigm in which the temporal alignment of auditory and visual stimuli was systematically varied. Moreover, the size of the spatial audio-visual ventriloquist effect was assessed. Adaptive training resulted in faster improvements compared to the control condition. Transfer effects were found for both tasks: The processing speed of auditory inputs and the size of the ventriloquist effect increased in the adaptive group following the training. We suggest that the relative precision of the temporal and spatial features of a cross-modal stimulus is weighted during multisensory integration. Thus, changes in the precision of temporal processing are expected to enhance the likelihood of multisensory integration for temporally aligned cross-modal stimuli
Consistency and Trends of Technological Innovations: A Network Approach to the International Patent Classification Data
No full textClassifying patents by the technology areas they pertain is important to enable information search and facilitate policy analysis and socio-economic studies. Based on the OECD Triadic Patent Family database, this study constructs a cohort network based on the grouping of IPC subclasses in the same patent families, and a citation network based on citations between subclasses of patent families citing each other. This paper presents a systematic analysis approach which obtains naturally formed network clusters identified using a Lumped Markov Chain method, extracts community keys traceable over time, and investigates two important community characteristics: consistency and changing trends. The results are verified against several other methods, including a recent research measuring patent text similarity. The proposed method contributes to the literature a network-based approach to study the endogenous community properties of an exogenously devised classification system. The application of this method may improve accuracy and efficiency of the IPC search platform and help detect the emergence of new technologies