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The 3D geometries of high-redshift galaxies remain poorly understood. We build a differentiable Bayesian model and use Hamiltonian Monte Carlo to efficiently and robustly infer the 3D shapes of star-forming galaxies in James Webb Space Telescope Cosmic Evolution Early Release Science observations with $\mathrm{log}{M}_{* }/{M}_{\odot }=9.0\mbox{--}10.5$ at z = 0.5–8.0. We reproduce previous results from the Hubble Space Telescope Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey in a fraction of the computing time and constrain the mean ellipticity, triaxiality, size, and covariances with samples as small as ∼50 galaxies. We find high 3D ellipticities for all mass–redshift bins, suggesting oblate (disky) or prolate (elongated) geometries. We break that degeneracy by constraining the mean triaxiality to be ∼1 for $\mathrm{log}{M}_{* }/{M}_{\odot }=9.0\mbox{--}9.5$ dwarfs at z > 1 (favoring the prolate scenario), with significantly lower triaxialities for higher masses and lower redshifts indicating the emergence of disks. The prolate population traces out a “banana” in the projected $b/a\mbox{--}\mathrm{log}a$ diagram with an excess of low- b / a , large- $\mathrm{log}a$ galaxies. The dwarf prolate fraction rises from ∼25% at z = 0.5–1.0 to ∼50%–80% at z = 3–8. Our results imply a second kind of disk settling from oval (triaxial) to more circular (axisymmetric) shapes with time. We simultaneously constrain the 3D size–mass relation and its dependence on 3D geometry. High-probability prolate and oblate candidates show remarkably similar Sérsic indices ( n ∼ 1), nonparametric morphological properties, and specific star formation rates. Both tend to be visually classified as disks or irregular, but edge-on oblate candidates show more dust attenuation. We discuss selection effects, follow-up prospects, and theoretical implications.

The attention on blockchain technology (BCT) to create new forms of relational reliance has seen an explosion of new applications and initiatives, to assure decentralized security and trust. Its potential as a game-changing technology relates to how data gets distributed and replicated over several organizations and countries. This paper provides an introduction to BCT, as well as a review of its technological aspects. A concrete application of outsource access control and pricing procedures in cellular networks, based on a decentralized access control-as-a-service solution for private cellular networks, is also presented. The application can be used by service and content providers, to provide new business models. The proposed method removes the single point of failure from conventional centralized access control systems, increasing scalability while decreasing operational complexity, regarding access control and pricing procedures. Design and implementation details of the new method in a real-world scenario using a private cellular network and a BCT system that enables smart contracts are also provided.

The dramatic rise in internet-based service provisioning has highlighted the importance of deploying scalable access control methods, facilitating service authorization for eligible users. Existing centralized methods suffer from single-point-of-failure, low scalability, and high computational overhead. In addition, in these methods, users pay for the service provider as well as the network provider independently for a specific service, imposing extra cost for the user. New business models are needed to resolve such shortcomings. The realization of these models calls for sophisticated access control methods which consider the requirements of all parties who want to: 1) access a service; 2) provide that service; and 3) provide the network connection. Blockchain is an enabling technology that provides unprecedented opportunities to novel distributed access control methods for new business models. We propose an Attribute-based access control solution by leveraging Blockchain to share network providers’ and service providers’ resources. Our solution offers access flexibility based on the requirements of the parties while fulfilling reliability, accountability, and immutability. Besides, it decreases the overall service cost which is beneficial for each party. Our solution makes it possible for service providers to outsource their access control procedures without requiring a trusted third party. The experiments confirm that our solution can provide a fast, comprehensive, and scalable access control mechanism.

Context aware communication services rely on information sources and sensors, to derive users’ current situation and potential needs, and to adapt their communication services accordingly. If extensive studies have been driven on context awareness by industrials and researchers from academia, the design of such systems without modifying uses and manners of underlying communication services—while keeping them simple, intuitive, and reactive—remains a challenge. In this work, we introduce a context aware communication system that takes into account user’s preferences, workload, and situation to customize telephony services. In this implementation, we use IMS for communication management. The benefits of this implementation are the enhancement of IMS with context awareness features, and the coupling of user preferences with contextual information to provide improved service customization, without modifying the user experience.