علیرضا منصوری

Knowing the current public opinion and predicting its trend using opinion formation models is very applicable. The social impact model of opinion formation is a discrete binary opinion model. It describes how interactions among individuals and sharing their opinions about a specific topic in a social network affect the dynamics of their opinions and form the opinion of society. The society could be an online social network. In this research, we considered the effect of segregation on opinion formation. Segregation is a phenomenon that happens due to homophily and is measured based upon network topology. Homophily is the tendency of individuals to interact with others who share similar traits. We used scale-free networks to model interactions between individuals. The social impact model includes a noise parameter, which is the stochastic part of the model, dealing with the inexplicable behavior of individuals and the effects of other influentials, e.g., mass media. Since this noise is a white noise with no bias toward any possible opinion, for simplicity, we assumed a noise-free social impact model, which is valid in equilibrium analysis we considered. The results reveal that with the same attributes for the individuals, the more segregated opinion group dominates the less segregated opinion group on average. Therefore, with the same population size and individual characteristics of both opinion groups, segregation is an overall influential factor for opinion formation. A more segregated opinion group attracts some individuals from the other group and becomes the majority opinion group of society in equilibrium.

Opinion formation is a collective behavior, describing the dynamics of people’s opinions due to their interactions. Nowadays, social media are broadly used and cause a lot of interactions among users who mainly know each other merely as a username, but significantly influence each others’ opinions and emotions. Both emotions and opinions spread across users in social media via their exchanged posts. Furthermore, based on psychology research, emotion affects people’s opinion. In this research, we implemented two binary classifiers to predict the users’ next opinions considering previous posts sent in online community: an original classifier, a classifier based on the social impact model of opinion formation; and an emotion-integrated classifier, a classifier based on the social impact model of opinion formation integrated with an emotion model to achieve an improved model. To evaluate the improved classifier, we used a dataset containing some debates from the CreateDebate.com website and compared the performance of the original classifier with the performance of the emotion integrated classifier. The experiment results show that considering emotions improves the accuracy and precision of the social impact model of opinion formation in social media.

Recently, supercomputers and high-performance computing (HPC) have caused significant progress in many fields, including industrial and research fields of artificial intelligence, data science, big data, Internet of Things, as well as large scale web applications. Regarding this characteristic, the supercomputer field becomes one of the strategic issues in developed and developing countries. Successful HPC development requires a robust infrastructure that effectively depends on a multidimensional policy and roadmap, covering all aspects of HPC services. In this regard, a comprehensive roadmap is necessary to design and achieve high-performance computing services. This paper proposes a comprehensive roadmap focusing on several strategic areas, including research activities, infrastructure and platforms, data processing, standard regulations, applied services, and business development. The roadmap follows an evolutionary strategy where strategic regions evolve in parallel. Also, in this paper, the Supercomputing Development Readiness Indicators (SDRI) inspired by the "Network Readiness Indicators" (NRI) are presented and the proposed roadmap uses them. The proposed roadmap is then compared with two other hypothetical roadmaps with the timing and priority of different strategic areas in terms of progress and completion time. Evaluation of the proposed roadmap based on the SDRI specification shows the effectiveness of the proposed method in creating and developing the services of a petaflops scale supercomputer.

Artifacts are ubiquitous and influential in our world, but their nature and existence are controversial. Several theories have been proposed to explain the ontology of artifacts. Drawing on Popper's theory of three worlds, this paper suggests a metaphysics for artifacts along the line of a critical rationalist (CR) approach. This theory distinguishes between three realms of reality: the physical world (World 1), the mental world (World 2), and the world of objective knowledge (World 3). The paper argues that artifacts have different ontological components that correspond to these three realms, and that each component is real and causal. The paper shows how this perspective can account for the intentional and functional aspects of artifacts, as well as their dependence on plans that influence different realms of reality. The paper explains how this pluralistic ontology, compared to the rival theories, enables one to explain the relevant ontological problems of artifacts. The paper also explores how this proposal can lead to a research program encompassing a broader range of technologies, such as social artifacts. In sum, the paper suggests that Popper's three worlds theory provides a rich and comprehensive framework for understanding the metaphysics of artifacts.