259 research outputs found
A Markovian and Roe-algebraic approach to asymptotic expansion in measure
In this paper, we conduct further studies on geometric and analytic
properties of asymptotic expansion in measure. More precisely, we develop a
machinery of Markov expansion and obtain an associated structure theorem for
asymptotically expanding actions. Based on this, we establish an analytic
characterisation for asymptotic expansion in terms of the Dru\c{t}u-Nowak
projection and the Roe algebra of the associated warped cones. As an
application, we provide new counterexamples to the coarse Baum-Connes
conjecture
Towards Secure Blockchain-enabled Internet of Vehicles: Optimizing Consensus Management Using Reputation and Contract Theory
In Internet of Vehicles (IoV), data sharing among vehicles is essential to
improve driving safety and enhance vehicular services. To ensure data sharing
security and traceability, highefficiency Delegated Proof-of-Stake consensus
scheme as a hard security solution is utilized to establish blockchain-enabled
IoV (BIoV). However, as miners are selected from miner candidates by
stake-based voting, it is difficult to defend against voting collusion between
the candidates and compromised high-stake vehicles, which introduces serious
security challenges to the BIoV. To address such challenges, we propose a soft
security enhancement solution including two stages: (i) miner selection and
(ii) block verification. In the first stage, a reputation-based voting scheme
for the blockchain is proposed to ensure secure miner selection. This scheme
evaluates candidates' reputation by using both historical interactions and
recommended opinions from other vehicles. The candidates with high reputation
are selected to be active miners and standby miners. In the second stage, to
prevent internal collusion among the active miners, a newly generated block is
further verified and audited by the standby miners. To incentivize the standby
miners to participate in block verification, we formulate interactions between
the active miners and the standby miners by using contract theory, which takes
block verification security and delay into consideration. Numerical results
based on a real-world dataset indicate that our schemes are secure and
efficient for data sharing in BIoV.Comment: 12 pages, submitted for possible journal publicatio
Rethinking Quality of Experience for Metaverse Services: A Consumer-based Economics Perspective
The Metaverse is considered to be one prototype of the next-generation
Internet, which contains people's expectations for the future world. However,
the academic discussion of the Metaverse still mainly focused on the system
technical design, and few research studied Metaverse challenges from the
perspective of consumers, i.e., Metaverse users. One difficulty is that the
analysis from the consumer's perspective requires interdisciplinary theoretical
framework and quantifiable Quality of Experience (QoE) measurements. In this
article, pioneering from consumers' point of view, we explore an interaction
between Metaverse system design and consumer behaviors. Specifically, we
rethink the QoE and propose an interdisciplinary framework that encompasses
both the Metaverse service providers (MSPs) and consumer considerations. From
the macro perspective, we introduce a joint optimization scheme that
simultaneously considers the Metaverse system design, consumers' utility, and
profitability of the MSPs. From the micro perspective, we advocate the
Willingness-to-Pay (WTP) as an easy-to-implement QoE measurement for future
Metaverse system studies. To illustrate the usability of the proposed
integrated framework, a use case of Metaverse, i.e., virtual traveling, is
presented. We show that our framework can benefit the MSPs in offering
competitive and economical service design to consumers while maximizing the
profit
- …