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1

On applications of quasi-Abelian Cayley graphs to Denial-of-Service protection

Girejko Ewa, Malinowska Agnieszka B.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2024

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Vol. 72, nr 3

art. no. e149232

EN

This paper addresses the problem of designing secure control for networked multi-agent systems (MASs) under Denial-of-Service (DoS) attacks. We propose a constructive design method based on the interaction topology. The MAS with a non-attack communication topology, modelled by quasi-Abelian Cayley graphs subject to DoS attacks, can be represented as a switched system. Using switching theory, we provide easily implementable sufficient conditions for the networked MAS to remain asymptotically stable despite DoS attacks. Our results are applicable to both continuous-time and discrete-time systems, as well as to discrete-time systems with variable steps or systems that combine discrete and continuous times.

2

Fuzzy Alliance and Coalitions that Can Be Formed by Alliance Agents

Mashkov Viktor, Smolarz Andrzej, Lytvynenko Volodymyr

International Journal of Electronics and Telecommunications

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2023

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Vol. 69, No. 4

713--718

EN

The paper deals with alliances and coalitions that can be formed by agents or entities. It is assumed that alliance agents cooperate and form coalitions for performing the tasks or missions. It is considered that alliance agents are unselfish. That is, they are more interested in achieving the common goal(s) than in getting personal benefits. In the paper, the concept of fuzzy alliance was introduced. A fuzzy alliance is considered as generalization of traditional alliance allowing agents to decide on the capabilities that their agents can and wanted deliver to coalition. Coalitions that can be formed by fuzzy alliance agents were considered. The definition of the “best” coalition was explained. The method of how to find the “best” coalition among all possible coalitions was suggested and verified by computer simulation.

3

Controllability of consensus heterogeneous multi-agent networks over continuous time scale

Athira V. S., Muni Vijayakumar S., Rafeek Kallu Vetty Muhammed, Reddy Gudala Janardhana

Control and Cybernetics

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2023

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Vol. 52, No. 2

199--245

EN

The research, presented in this paper, concernes the controllability of a multi-agent network with a directed, unweighted, cooperative, and time-invariant communication topology. The network’s agents follow linear and heterogeneous dynamics, encompassing first-order, second-order, and third-order differential equations over continuous time. Two classes of neighbour-based linear distributed control protocols are considered: the first one utilises average feedback from relative velocities/relative accelerations, and the second one utilises feedback from absolute velocities/absolute accelerations. Under both protocols, the network’s agents achieve consensus in their states asymptotically. We observe that both of the considered dynamical rules exploit the random-walk normalised Laplacian matrix of the network’s graph. By categorising the agents of the network into leaders and followers, with leaders serving as exogenous control inputs, we analyse the controllability of followers within their state space through the influence of leaders. Specifically, matrix-rank conditions are established to evaluate the leader– follower controllability of the network under both control protocols. These matrix-rank conditions are further refined in terms of the system matrices’ eigenvalues and eigenvectors. The inference diagrams presented in this work provide deeper insights into how leader– follower interactions impact the network controllability. The efficacy of the theoretical findings is validated through numerical examples.

4

On impact of disturbance in the deployment problem of multi-agent system

Topolewicz Katarzyna, Olaru Sorin, Girejko Ewa, Dórea Carlos E.T.

Archives of Control Sciences

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2023

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Vol. 33, No. 2

299--320

EN

The paper is dedicated to the robustness analysis of scalar multi-agent dynamical systems. The open problem we aim to address is the one related to the impact of additive disturbances. Set-theoretic methods are used to achieve the main results in terms of positive invariance and admissible bounds on the disturbances.

5

Concept of separation method between aircraft in the transition period

Żuchowska Daria, Stelmach Anna

Prace Naukowe Politechniki Warszawskiej. Transport

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2022

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z. 135

5--16

EN

The current concept of air traffic control based on human work was created many years ago and is now approaching the limit of its performance. Therefore, new concepts for air traffic control are being sought. One of the ideas is to delegate the responsibility for ensuring separation between aircraft to aircraft crews. The issue of self-separation is quite a difficult task. Analysis of the literature concludes that the transition from one phase to another will occur in stages. This paper focuses on the transition period. The concept of a method of ensuring separation when changing traffic organization was proposed. A vital element of the separation method in the transition period is to define the negotiation and communication process between aircraft, which was presented in this paper.

6

An Intelligent Method for the Scheduling of Cyber Physical Production Systems

Khadiri Hassan, Sekkat Souhail, Herrou Brahim

Management and Production Engineering Review

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2022

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Vol. 13, No. 1

44--51

EN

The new industrial era, industry 4.0, leans on Cyber Physical Systems CPS. It is an emergent approach of Production System design that consists of the intimate integration between physical processes and information computation and communication systems. The CPSs redefine the decision-making process in shop floor level to reach an intelligent shop floor control. The scheduling is one of the most important shop floor control functions. In this paper, we propose a cooperative scheduling based on multi-agents modelling for Cyber Physical Production Systems. To validate this approach, we describe a use case in which we implement a scheduling module within a flexible machining cell control tool.

7

Distributed event-triggered generalized Nash equilibrium seeking for aggregative games on unbalanced digraphs

Cai Xin, Nan Xinyuan, Gao Bingpeng

Archives of Control Sciences

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2022

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Vol. 32, No. 4

783--800

EN

This paper addresses the problem of seeking generalized Nash equilibrium for constrained aggregative games with double-integrator agents who communicate with each other on an unbalanced directed graph. An auxiliary variable is introduced to balance the consensus terms in the designed algorithm by estimating the left eigenvector of the Laplacian matrix associated with the zero eigenvalue in a distributed manner. Moreover, an event-triggered broadcasting scheme is proposed to reduce communication loads in the network. It is shown that the proposed communication scheme is free of the Zeno behavior and the asymptotic convergence of the designed algorithm is obtained. Simulation results are demonstrated to validate the proposed methods.

8

Evacuation by leader-follower model with bounded confidence and predictive mechanisms

Almeida Ricardo, Girejko Ewa, Machado Luis, Malinowska Agnieszka B., Martins Natália

Archives of Control Sciences

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2021

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Vol. 31, No. 3

629--644

EN

This paper studies an evacuation problem described by a leader-follower model with bounded confidence under predictive mechanisms. We design a control strategy in such a way that agents are guided by a leader, which follows the evacuation path. The proposed evacuation algorithm is based on Model Predictive Control (MPC) that uses the current and the past information of the system to predict future agents’ behaviors. It can be observed that, with MPC method, the leader-following consensus is obtained faster in comparison to the conventional optimal control technique. The effectiveness of the developed MPC evacuation algorithm with respect to different parameters and different time domains is illustrated by numerical examples.

9

An Agent-based Cyber-Physical Production System using Lego Technology

Mustafa Yalcin Metehan, Karaduman Burak, Kardas Geylani, Challenger Moharram

Annals of Computer Science and Information Systems

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2021

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Vol. 25

521--531

EN

To cope with the challenges of constructing Cyber-physical Production Systems (CPPS), many studies propose benefiting from agent systems. However, industrial processes should be mostly emulated while agent-based solutions are integrating with CPPS since it is not always possible to apply cyber-based solutions to these systems directly. The target system can be miniaturised while sustaining its functionality. Hence, in this paper, we introduce an agent-based industrial production line and discuss the system development using Lego technology while providing integration of software agents as well as focusing on low-level requirements. In this way, a CPPS is emulated while agents control the system.

10

A Time-Sensitive Model for Data Tampering Detection for the Advanced Metering Infrastructure

Blanco José Miguel, Rossi Bruno, Pitner Tomas

Annals of Computer Science and Information Systems

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2021

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Vol. 25

511--519

EN

Smart Grids offer multiple benefits: efficient energy provision, quicker recoveries from failures, etc. Nevertheless, there is risk of data tampering, unsolicited modification of the data of the smart meters. The main aim of this paper is to provide a model for processing the smart meter data that flags any energy consumption level that could be indication of data tampering. The proposed model is time-sensitive, allowing for tracking the energy usage along time, thus making possible the detection of long-lasting abnormal levels of energy consumption. Such model can be integrated in an anomaly detection system and in a semantic web reasoner.

11

Multi agent deep learning with cooperative communication

Simões David, Lau Nuno, Reis Luís Paulo

Journal of Artificial Intelligence and Soft Computing Research

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2020

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Vol. 10, No. 3

189--207

EN

We consider the problem of multi agents cooperating in a partially-observable environment. Agents must learn to coordinate and share relevant information to solve the tasks successfully. This article describes Asynchronous Advantage Actor-Critic with Communication (A3C2), an end-to-end differentiable approach where agents learn policies and communication protocols simultaneously. A3C2 uses a centralized learning, distributed execution paradigm, supports independent agents, dynamic team sizes, partiallyobservable environments, and noisy communications. We compare and show that A3C2 outperforms other state-of-the-art proposals in multiple environments.

12

StarCraft agent strategic training on a large human versus human game replay dataset

Krištofík Štefan, Malík Peter, Kasáš Matúš, Neupauer Štefan

Annals of Computer Science and Information Systems

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2020

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Vol. 21

391--399

EN

Real-time strategy games are currently very popular as a testbed for AI research and education. StarCraft: Brood War (SC:BW) is one of such games. Recently, a new large, unlabeled human versus human SC:BW game replay dataset called STARDATA was published. This paper aims to prove that the player strategy diversity requirement of the dataset is met, i.e., that the diversity of player strategies in STARDATA replays is of sufficient quality. To this end, we built a competitive SC:BW agent from scratch and trained its strategic decision making process on STARDATA. The results show that in the current state of the competitive environment the agent is capable of keeping a stable rating and a decent win rate over a longer period of time. It also performs better than our other, simple rule-based agent. Therefore, we conclude that the strategy diversity requirement of STARDATA is met.

13

Fine tuning of agent-based evolutionary computing

Mizera Michal, Nowotarski Pawel, Byrski Aleksander, Kisiel-Dorohinicki Marek

Journal of Artificial Intelligence and Soft Computing Research

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2019

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Vol. 9, No. 2

81--97

EN

Evolutionary Multi-agent System introduced by late Krzysztof Cetnarowicz and developed further at the AGH University of Science and Technology became a reliable optimization system, both proven experimentally and theoretically. This paper follows a work of Byrski further testing and analyzing the efficacy of this metaheuristic based on popular, high-dimensional benchmark functions. The contents of this paper will be useful for anybody willing to apply this computing algorithm to continuous and not only optimization.

14

Towards fully decentralized multi-objective energy scheduling

Bremer Jörg, Lehnhoff Sebastian

Annals of Computer Science and Information Systems

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2019

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Vol. 18

193--201

EN

Future demand for managing a huge number of individually operating small and often volatile energy resources within the smart grid is preponderantly answered by involving decentralized orchestration methods for planning and scheduling. Many planning and scheduling problems are of a multi-objective nature. For the single-objective case - e.g. predictive scheduling with the goal of jointly resembling a wanted target schedule - fully decentralized algorithms with self-organizing agents exist. We extend this paradigm towards fully decentralized agent-based multi-objective scheduling for energy resources e.g. in virtual power plants for which special local constraint-handling techniques are needed. We integrate algorithmic elements from the well-known S-metric selection evolutionary multi-objective algorithm into a gossiping-based combinatorial optimization heuristic that works with agents for the single-objective case and derive a number of challenges that have to be solved for fully decentralized multi-objective optimization. We present a first solution approach based on the combinatorial optimization heuristics for agents and demonstrate viability and applicability in several simulation scenarios.

15

Monitoring of flood embankments with the use of tomographic systems with distributed architecture

Rymarczyk T., Cieplak T., Tchórzewski P., Kłosowski G., Sikora J.

Przegląd Elektrotechniczny

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2018

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R. 94, nr 12

170--173

EN

The subject of the presented article are studies on the automatic and reliable method of observing flood embankments using a multisensor integrated monitoring system. Designing and developing this type of system is a serious challenge, mainly due to the need to involve experienced specialists and scientists from various fields of science and technology. An element of such a system is the electrical tomograph presented in the article for non-destructive testing. With the help of the presented tomographic system, it is possible to carry out tests of technical objects such as flood barriers and industrial tanks. The described monitoring system, in addition to the software, consists of many subsystems and components, of which sensors play a special role. With their help, the system measures various types of physical parameters, including: wind speed, ambient temperature, voltage, etc. In this text, the authors focused on one of the subsystems of the described solution, namely on the electrical tomography. The principle of operation of the discussed system is based on the observation of the environment using many differentiated, intelligent measurement methods. In addition, an analytical module based on computational intelligence algorithms is an important element of the monitoring system. This module is used to analyze and visualize input data.

PL

Przedmiotem prezentowanego artykułu są badania nad automatyczną i niezawodną metodą obserwacji obwałowań przeciwpowodziowych za pomocą wieloczujnikowego zintegrowanego systemu monitorowania. Projektowanie i opracowywanie tego typu systemu stanowi poważne wyzwanie, głównie ze względu na konieczność zaangażowania doświadczonych specjalistów i naukowców z różnych dziedzin nauki i techniki. Elementem takiego systemu jest tomograf elektryczny umożliwiający badania nieniszczące. Za pomocą systemu tomograficznego można przeprowadzać skanowanie obiektów technicznych, takich jak zapory przeciwpowodziowe i zbiorniki przemysłowe. Opisywany system monitorowania, oprócz oprogramowania, składa się z wielu podsystemów i komponentów, z których czujniki odgrywają szczególną rolę. Za ich pomocą system mierzy różne rodzaje parametrów, w tym: prędkość wiatru, temperaturę otoczenia, napięcie itp. W artykule skoncentrowano się na jednym z podsystemów przedmiotowego systemu, a mianowicie na tomografii elektrycznej. Zasada działania systemu monitorowania oparta jest na obserwacji środowiska przy użyciu wielu zróżnicowanych, inteligentnych metod pomiarowych. Ponadto ważnym elementem systemu jest moduł analityczny oparty na algorytmach inteligencji obliczeniowej. Moduł ten służy do analizy i wizualizacji danych wejściowych.

16

Nonlinear convergence algorithm: structural properties with doubly stochastic quadratic operators for multi-agent systems

Abdulghafor R., Turaev S., Zeki A., Abubaker A.

Journal of Artificial Intelligence and Soft Computing Research

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2018

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Vol. 8, No. 1

49--61

EN

This paper proposes nonlinear operator of extreme doubly stochastic quadratic operator (EDSQO) for convergence algorithm aimed at solving consensus problem (CP) of discrete-time for multi-agent systems (MAS) on n-dimensional simplex. The first part undertakes systematic review of consensus problems. Convergence was generated via extreme doubly stochastic quadratic operators (EDSQOs) in the other part. However, this work was able to formulate convergence algorithms from doubly stochastic matrices, majorization theory, graph theory and stochastic analysis. We develop two algorithms: 1) the nonlinear algorithm of extreme doubly stochastic quadratic operator (NLAEDSQO) to generate all the convergent EDSQOs and 2) the nonlinear convergence algorithm (NLCA) of EDSQOs to investigate the optimal consensus for MAS. Experimental evaluation on convergent of EDSQOs yielded an optimal consensus for MAS. Comparative analysis with the convergence of EDSQOs and DeGroot model were carried out. The comparison was based on the complexity of operators, number of iterations to converge and the time required for convergences. This research proposed algorithm on convergence which is faster than the DeGroot linear model.

17

Multiagent Approach to Fuzzy-Linguistic Knowledge Integration

Modliński Ł., Popek G.

Computational Methods in Science and Technology

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2018

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Vol. 24, No. 4

317--336

EN

The paper aims to give at least a partial answer to an urgent need for knowledge processing systems equipped with semantic capabilities. One of the crucial goals is to reflect inner computational models and numerical data outside of the system by presenting linguistic statements easily understood by a non-expert user. The paper follows a motivational scenario and presents a layered approach to knowledge integration. The fundamental rationale behind the proposed approach is that a degree of inconsistency of the whole body of knowledge should be incorporated into the formed summary and conveyed to the external user of the system. The paper deals with a practically important problem of processing modal epistemic statements about an object exhibiting some set of fuzzy properties. The statements represent distributed knowledge of some agent population and are represented on the level of a semi-natural language. In particular, the paper describes an approach to two-level fuzzy-linguistic knowledge integration based on the consensus-theory and clustering methods. In particular, it discusses the difference between the in-cluster level and the cross-cluster level. While this paper considers an environment limited to a single object with multiple properties, it is directly extendable to environments with multiple objects. The reduction is purely technical as it allows for a simplification of a notation and presented descriptions.

18

Hybridization of Multi-Agent Optimization Methods Applied to the Calibration Process of Reservoir Modelling

Łętkowski P.

Prace Naukowe Instytutu Nafty i Gazu

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2016

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nr 209 wyd. konferencyjne

837--842

EN

Multi-agent system denotes a group of agents (solutions) that cooperate and exchange information in order to meet the common target of finding a minimum of a given function and, thus, to realize the optimization method. These methods are typically modified for enhancing their effectiveness – the process called hybridization. This presentation includes the effects of hybridization applied to the method of Particle Swarm Optimization used to solve the problem of reservoir model calibration. In mathematical terms the calibration problem is an example of an optimization problem that cannot be solved with traditional methods because: (i) the problem is ill-posed, (ii) the problem is of the global optimization type (iii) the space of solutions is multidimensional with a big number of dimensions, (iv) the target function evaluation is very time consuming. The hybridization applied to the method is shown to be more convergent and effective than the original one.

PL

Pod pojęciem optymalizacyjnych systemów wieloagentowych należy rozumieć grupę agentów (rozwiązań), które współpracują wymieniając informacje w celu osiągnięcia wspólnego celu, którym jest znalezienie globalnego minimum funkcji. Metody te są nierzadko modyfikowane – proces ten nazywa się hybrydyzacją. W pracy przedstawiono efekty hybrydyzacji wybranej wieloagentowej metody optymalizacyjnej przy kalibracji symulacyjnego modelu złożowego. Z matematycznego punktu widzenia problem kalibracyjny jest przykładem problemu optymalizacyjnego, który nie może być rozwiązany metodami tradycyjnymi, ponieważ: (i) jest źle uwarunkowany, (ii) jest problemem optymalizacji globalnej, (iii) przestrzeń rozwiązań jest wielowymiarowa z dużą liczba wymiarów, (iv) wyznaczenie funkcji celu jest czasochłonne. Zastosowana hybrydyzacja wskazuje na istotną poprawę zbieżności i efektywności w porównaniu z oryginalną metodą optymalizacji.

19

Potential of Multi-Agent Systems for Operation of Transportation Systems

Madejski J.

Pomiary Automatyka Robotyka

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2016

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R. 20, nr 1

31--36

EN

The article discusses the possibility of implementation of the currently available solutions with software agents in transport, focusing on applications for planning transport systems, control, monitoring and analysis of the state of the superstructure and potential applications to the planning of the maintenance tasks.

PL

W artykule omówiono możliwość zastosowania dostępnych obecnie rozwiązań z agentami programowymi w transporcie, koncentrując się na zastosowaniach do planowania systemów transportowych, sterowania nimi, monitorowania i analizy stanu nawierzchni kolejowej, a także możliwymi zastosowaniami do planowania prac utrzymaniowych.

20

Off-line and dynamic production scheduling - a comparative case study

Bożek A., Wysocki M.

Management and Production Engineering Review

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2016

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Vol. 7, No. 1

21--32

EN

A comprehensive case study of manufacturing scheduling solutions development is given. It includes highly generalized scheduling problem as well as a few scheduling modes, methods and problem models. The considered problem combines flexible job shop structure, lot streaming with variable sublots, transport times, setup times, and machine calendars. Tabu search metaheuristic and constraint programming methods have been used for the off-line scheduling. Two dynamic scheduling methods have also been implemented, i.e., dispatching rules for the completely reactive scheduling and a multi-agent system for the predictivereactive scheduling. In these implementations three distinct models of the problem have been used, based on: graph representation, optimal constraint satisfaction, and Petri net formalism. Each of these solutions has been verified in computational experiments. The results are compared and some findings about advantages, disadvantages, and suggestions on using the solutions are formulated.