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1

Proof-of-Miner-Clustering-Authentication Consensus Method of Blockchain for IoT Networks

Huynh Tam T., Huynh Chinh N., Nguyen Thanh H.

Annals of Computer Science and Information Systems

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2022

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Vol. 33

141--144

EN

Using blockchain technology in the Internet of Things (IoT) security is a research trend in recent years. With large IoT networks, miners will have to verify a lot of transactions broadcast from IoT devices. This can cause a delay in saving valid transactions to the ledger. This paper proposes a proof-of-miner-clustering-authentication consensus method of blockchain for IoT networks. In the proposed method, miners in a blockchain network will be clustered, each miner in a cluster is responsible for verifying transactions from IoT devices in the area it manages. Mining of new blocks between clusters is done by the round robin method. Our consensus method can apply to private or consortium blockchain networks, helping to improve the transaction verification speed of miners.

2

A Hybrid Protocol to Solve Authenticated Byzantine Consensus

Tioura Abdelhamid, Moumen Hamouma, Kalla Hamoudi, Ait Saidi Ahmed

Fundamenta Informaticae

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2020

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Vol. 173, nr 1

73--89

EN

The consensus is a central problem of fault-tolerant distributed computing. Unfortunately, solving such a problem is impossible in asynchronous distributed systems prone to process failures. To circumvent this impossibility (known as FLP impossibility result) in a deterministic way, on top of asynchronous distributed systems enriched with additional assumptions, several protocols have been proposed. Actually, to solve the Byzantine Consensus problem, with a deterministic manner, in systems where at most t processes may exhibit a Byzantine behavior, two approaches have been investigated. The first relies on the addition of synchrony, called Timer-Based, while the second, called Time-Free, is based on the pattern of message exchange. This paper shows that both types of assumptions are not antagonist and can be combined to solve authenticated Byzantine consensus. The combined assumption considers a correct process pi, called ⋄〈t + 1〉-BW, and a set X of t+1 correct processes (including pi itself) such that, eventually, for each query broadcasted by a correct process pj of X, pj receives a response from pi ∈ X among the (n – t) first responses to that query or both links connecting pi and pj are timely. Based on this combination, a simple hybrid authenticated Byzantine consensus protocol benefiting from the best of both worlds is proposed. As a matter of fact, although numerous hybrid protocols have been designed for the consensus problem in the crash model, this is, to our knowledge, the first hybrid deterministic solution to the Byzantine consensus problem.

3

On the existence of optimal consensus control for the fractional Cucker-Smale model

Almeida R., Kamocki R., Malinowska A. B., Odzijewicz T.

Archives of Control Sciences

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2020

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Vol. 30, No. 4

625--651

EN

This paper addresses the nonlinear Cucker-Smale optimal control problem under the interplay of memory effect. The aforementioned effect is included by employing the Caputo fractional derivative in the equation representing the velocity of agents. Sufficient conditions for the existence of solutions to the considered problem are proved and the analysis of some particular problems is illustrated by two numerical examples.

4

Consensus for multiple unmanned surface vehicle (MUSV) systems with Markov switching topologies

Wang Liyuan, Yue Wei, Zhang Rubo

Polish Maritime Research

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2019

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nr 1

145--152

EN

This paper is concerned with sampled-data leader following consensus of multiple unmanned surface vehicle (MUSV) systems with random switching network topologies and wave-induced disturbance. By modelling the switching of network topologies with the use of a Markov process and considering the effect of wave-induced disturbance, a new sampleddata consensus control protocol is proposed. By employing an appropriate Lyapunov-Krosovskii function method and the weak infinitesimal operation, a novel stability criterion is derived, which ensures that the MUSV system can reach robustly leader-following consensus with H∞ performance satisfied. Based on this criterion, the Markov dependent switching consensus controller gains are obtained by solving a set of linear matrix inequalities. Finally, an illustrative example is given to verify the effectiveness of the proposed control scheme for MUSV systems.

5

Opinion formation in social networks

Taalaibekova A.

Operations Research and Decisions

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2018

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Vol. 28, No. 2

85--108

EN

A number of selected works on the dynamics of opinions and beliefs in social networks has been discussed. Both Bayesian and non-Bayesian approaches to social learning have been considered, but the analysis has been focused on a simple, tractable and widely used model of updating beliefs – the DeGroot model. The author studied the dynamics of opinions based on the DeGroot model from different points of view. First, its attractive features and shortcomings were discussed and then some of its extensions have been presented. These models are based on the DeGroot updating rule, but additionally incorporate the possibility of improvements and enrichments of the framework.

6

A continuous-time distributed algorithm for solving a class of decomposable nonconvex quadratic programming

Zhao Y., Liu Q.

Journal of Artificial Intelligence and Soft Computing Research

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2018

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Vol. 8, No. 4

283--291

EN

In this paper, a continuous-time distributed algorithm is presented to solve a class of decomposable quadratic programming problems. In the quadratic programming, even if the objective function is nonconvex, the algorithm can still perform well under an extra condition combining with the objective, constraint and coupling matrices. Inspired by recent advances in distributed optimization, the proposed continuous-time algorithm described by multi-agent network with consensus is designed and analyzed. In the network, each agent only accesses the local information of its own and from its neighbors, then all the agents in a connected network cooperatively find the optimal solution with consensus.

7

Behaviour of fractional discrete-time consensus models with delays for summator dynamics

Girejko E., Mozyrska D., Wyrwas M.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2018

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Vol. 66, nr 4

403--410

EN

The leader-following consensus problem of fractional-order multi-agent discrete-time systems with delays is considered. In the systems, interactions between agents are defined like in Krause and Cucker-Smale models, but the memory is included by taking both the fractional-order discrete-time operator on the left hand side of the nonlinear systems and the delays. Since in practical problems only bounded number of delays can be considered, we study the fractional order discrete-time models with a finite number of delays. The models of opinions under consideration are investigated for single- and double-summator dynamics of discrete-time by means of analytical methods as well as computer simulations.

8

Communication Complexity of Consensus in Anonymous Message Passing Systems

Fusco E. G., Pelc A.

Fundamenta Informaticae

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2015

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Vol. 137, nr 3

305--322

EN

We consider the message complexity of achieving consensus in synchronous anonymous message passing systems. Unlabeled processors (nodes) communicate through links of a network. An adversary wakes up some subset of processors at possibly different times and assigns them arbitrary numerical input values. All other processors are dormant and do not have input values. Any message wakes up a dormant processor. The goal of consensus is to have all processors agree on one of the input values. We seek deterministic consensus algorithms using as few messages as possible. As opposed to most of the literature on consensus, the difficulty of our scenario are not faults (we assume that the network is fault-free) but the arbitrary network topology combined with the anonymity of nodes. For n-node networks of unknown topology we show a consensus algorithm using Ώ(n2) messages; this complexity is optimal for this class. We show that if the network topology is known, then the complexity of consensus decreases significantly. Our main contribution is an algorithm that uses Ώ(n2/3 log2 n) messages on any n-node network and we show that some networks require (n log n) messages to achieve consensus.

9

Robust L2 consensus of high-order swarm systems with time-varying delays

Xi J, Yao Z, Liu G., Zhong Y.

Control and Cybernetics

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2014

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Vol. 43, no. 1

59--77

EN

Consensus problems for high-order continuous-time swarm systems in directed networks with time delays, uncertainties and external disturbances are investigated. Firstly, the state space of a swarm system is decomposed into a consensus subspace (CS) and a complement consensus space (CCS). A necessary and sufficient condition for the system with time delays and uncertainties to achieve consensus is presented based on the state projection on CCS, and an explicit expression of the consensus function is shown on the basis of the state projection on CS. Then, a sufficient condition for the system to achieve consensus with a desired L2 performance is given. Finally, numerical simulations are shown to demonstrate theoretical results.

10

Changing attitude patterns in group decision making process – a socio-technological approach

Falkiewicz D., Hołda M.

Czasopismo Techniczne. Automatyka

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2012

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R. 109, z. 1-AC

29--39

EN

This paper proposes a novel approach to consensus reaching process, which combines a mathematical model and socio-psychological factors. We attempt to correlate two decision support systems: one with the teacher managing the process of reaching consensus within the laboratory groups of individuals, and computer-based system, with mathematical presumptions as for the consistency of the model with the reality of a particular social group.

PL

Przedmiotem niniejszego artykułu jest nowatorskie podejście do procesu osiągania konsensusu, łączące matematyczny model z czynnikami społeczno-psychologicznym. Autorki podjęły się próby skorelowania dwóch systemów wspomagania decyzji: rzeczywistego z nauczycielem zarządzającym procesem osiągania konsensusu w laboratoryjnych grupach studentów, a także informatycznego, którego matematyczne założenia były zgodne z realnymi zachowaniami określonej grupy społecznej.

11

A matrix inequality based design method for consensus problems in multi-agent systems

Zhai G., Okuno S., Imae J., Kobayashi T.

International Journal of Applied Mathematics and Computer Science

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2009

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Vol. 19, no 4

639-646

EN

In this paper, we study a consensus problem in multi-agent systems, where the entire system is decentralized in the sense that each agent can only obtain information (states or outputs) from its neighbor agents. The existing design methods found in the literature are mostly based on a graph Laplacian of the graph which describes the interconnection structure among the agents, and such methods cannot deal with complicated control specification. For this purpose, we propose to reduce the consensus problem at hand to the solving of a strict matrix inequality with respect to a Lyapunov matrix and a controller gain matrix, and we propose two algorithms for solving the matrix inequality. It turns out that this method includes the existing Laplacian based method as a special case and can deal with various additional control requirements such as the convergence rate and actuator constraints.