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## Distributed Time Synchronization Algorithms and Opinion Dynamics

We propose new deterministic and stochastic models for synchronization of clocks in nodes of distributed networks. An external accurate time server is used to ensure convergence of the node clocks to the exact time. These systems have much in common with mathematical models of opinion formation in multiagent systems. There is a direct analogy between the *time server/node clocks* pair in asynchronous networks and the *leader/follower* pair in the context of social network models.

Constant changes in demand for resources in the market complicate planning and management of material flows. In current practice, it’s possible to solve this problem by applying multi-agent systems representing a set of interacting software objects called intelligent agents. The activity of an intelligent agent is directed at achieving individual goals, which may include the search of possibilities of delivery, storing goods, transportation of goods and other. The article considers models, technologies, the typical architecture of multi-agent system, analyzes the completed projects and describes the prospects for the development of multi-agent systems in logistics.

We consider Markov models of multicomponent systems with synchronizing interaction. Under natural regularity assumptions about the message routing graph, they have nice longtime behavior. We are interested in limit probability laws related to the steady state viewed from the center-of-mass coordinate system.

We consider Markov models of multicomponent systems with synchronizing interaction. Under natural regularity assumptions about the message routing graph, they have nice longtime behavior. We are interested in limit probability laws related to the steady state viewed from the center-of-mass coordinate system.

The Smart Innovation, Systems and Technologies book series encompasses the topics of knowledge, intelligence, innovation and sustainability. The aim of the series is to make available a platform for the publication of books on all aspects of single and multi-disciplinary research on these themes in order to make the latest results available in a readily-accessible form. Volumes on interdisciplinary research combining two or more of these areas is particularly sought.

The series covers systems and paradigms that employ knowledge and intelligence in a broad sense. Its scope is systems having embedded knowledge and intelligence, which may be applied to the solution of world problems in industry, the environment and the community. It also focusses on the knowledge-transfer methodologies and innovation strategies employed to make this happen effectively. The combination of intelligent systems tools and a broad range of applications introduces a need for a synergy of disciplines from science, technology, business andthe humanities. The series will include conference proceedings, edited collections, monographs, handbooks, reference books, and other relevant types of book in areas of science and technology where smart systems and technologies can offer innovative solutions.

High quality content is an essential feature for all book proposals accepted for the series. It is expected that editors of all accepted volumes will ensure that contributions are subjected to an appropriate level of reviewing process and adhere to KES quality principles.

This proceedings publication is a compilation of selected contributions from the “Third International Conference on the Dynamics of Information Systems” which took place at the University of Florida, Gainesville, February 16–18, 2011. The purpose of this conference was to bring together scientists and engineers from industry, government, and academia in order to exchange new discoveries and results in a broad range of topics relevant to the theory and practice of dynamics of information systems. Dynamics of Information Systems: Mathematical Foundation presents state-of-the art research and is intended for graduate students and researchers interested in some of the most recent discoveries in information theory and dynamical systems. Scientists in other disciplines may also benefit from the applications of new developments to their own area of study.

The Autonomous Agents and MultiAgent Systems (AAMAS) conference series brings together researchers from around the world to share the latest advances in the field. It is the premier forum for research in the theory and practice of autonomous agents and multi-agent systems. AAMAS 2002, the first of the series, was held in Bologna, followed by Melbourne (2003), New York (2004), Utrecht (2005), Hakodate (2006), Honolulu (2007), Estoril (2008), Budapest (2009), Toronto (2010), Taipei (2011), Valencia (2012), Saint Paul (2013), Paris (2014), and Istanbul (2015). This volume constitutes the proceedings of AAMAS 2016, the fifteenth conference in the series, held in Singapore in May 2016.

In line with previous editions, AAMAS 2016 attracted submissions for a general track and five special tracks: Innovative Applications, Robotics, Embodied Virtual Agents and Human-Agent Interaction, Blue Sky Ideas track, and the JAAMAS presentation track. The special tracks were chaired by leading researchers in their corresponding fields: Onn Shehory and Noa Agmon chaired the Innovative Applications track, Francesco Amigoni and Roderich Gross the Robotics track, Tim Bickmore and Hannes Vilhjálmsson the Embodied Virtual Agents and Human-Agent Interaction track, and Frank Dignum the Blue Sky Ideas track. As a new initiative, the chairs of AAMAS 2016 also solicited articles published in the Journal of Autonomous Agents and Multiagent Systems for the JAAMAS Presentation Track. Only papers that have appeared in the Journal of Autonomous Agents and Multi-agent Systems (JAAMAS) in the 12 months period preceding the AAMAS notification date were eligible. This new track was chaired by Peter Stone.

Jointly with the PC chairs the special track chairs were responsible for appointing the Programme Committee (PC) members and the Senior Programme Committee members (SPC) for their tracks, and they made acceptance/rejection recommendations for their tracks in consultation with Programme Chairs based on input provided by the track PC, SPC, and Area Experts. This year the PC chairs introduced the new role of Area Experts, i.e., SPC members with additional responsibilities, to assist with selecting SPC members for specific research areas, identifying appropriate keywords, and assisting in potential issues during discussion phase. This new role was a success and increased the quality of our SPC and PC, and also the reviewing process in general.

Full paper submissions (8 pages plus bibliographic references) and Blue Sky Ideas paper submissions (4 pages plus references) were solicited for AAMAS 2016. Some of the full paper submissions were accepted as extended abstracts (2 pages). The papers were selected by means of a thorough review and discussion process, which included an opportunity for authors to respond to reviewer comments during a rebuttal phase. All SPC members, Area Experts, and Track Chairs followed and contributed to the technical discussions on the papers they were overseeing. The JAAMAS presentation Track submissions published as extended abstracts were handled by the track chair.

Overall, out of 550 submissions, 137 (25%) were accepted as full papers and 143 (26%) were accepted as extended abstracts. Additionally, all 16 JAAMAS track submissions were accepted.

Full papers were presented orally in 20 minute slots; all extended abstracts and, optionally, full papers were presented as posters during the conference.

Out of the 550 submissions, 351 (64%) had a student as the primary author, 82 of these were accepted as full papers (23%), and a further 90 (26%) were accepted as extended abstracts.

The proceedings also contain 17 Demonstration papers, 13 Doctoral Consortium papers, as well as abstracts of the invited talks and details of some of the awards given.

Discusses the formulation of the problem of increasing the efficiency of modelling of multicomponent IoT systems

A model for organizing cargo transportation between two node stations connected by a railway line which contains a certain number of intermediate stations is considered. The movement of cargo is in one direction. Such a situation may occur, for example, if one of the node stations is located in a region which produce raw material for manufacturing industry located in another region, and there is another node station. The organization of freight traﬃc is performed by means of a number of technologies. These technologies determine the rules for taking on cargo at the initial node station, the rules of interaction between neighboring stations, as well as the rule of distribution of cargo to the ﬁnal node stations. The process of cargo transportation is followed by the set rule of control. For such a model, one must determine possible modes of cargo transportation and describe their properties. This model is described by a ﬁnite-dimensional system of diﬀerential equations with nonlocal linear restrictions. The class of the solution satisfying nonlocal linear restrictions is extremely narrow. It results in the need for the “correct” extension of solutions of a system of diﬀerential equations to a class of quasi-solutions having the distinctive feature of gaps in a countable number of points. It was possible numerically using the Runge–Kutta method of the fourth order to build these quasi-solutions and determine their rate of growth. Let us note that in the technical plan the main complexity consisted in obtaining quasi-solutions satisfying the nonlocal linear restrictions. Furthermore, we investigated the dependence of quasi-solutions and, in particular, sizes of gaps (jumps) of solutions on a number of parameters of the model characterizing a rule of control, technologies for transportation of cargo and intensity of giving of cargo on a node station.

Let k be a field of characteristic zero, let G be a connected reductive algebraic group over k and let g be its Lie algebra. Let k(G), respectively, k(g), be the field of k- rational functions on G, respectively, g. The conjugation action of G on itself induces the adjoint action of G on g. We investigate the question whether or not the field extensions k(G)/k(G)^G and k(g)/k(g)^G are purely transcendental. We show that the answer is the same for k(G)/k(G)^G and k(g)/k(g)^G, and reduce the problem to the case where G is simple. For simple groups we show that the answer is positive if G is split of type A_n or C_n, and negative for groups of other types, except possibly G_2. A key ingredient in the proof of the negative result is a recent formula for the unramified Brauer group of a homogeneous space with connected stabilizers. As a byproduct of our investigation we give an affirmative answer to a question of Grothendieck about the existence of a rational section of the categorical quotient morphism for the conjugating action of G on itself.

Let G be a connected semisimple algebraic group over an algebraically closed field k. In 1965 Steinberg proved that if G is simply connected, then in G there exists a closed irreducible cross-section of the set of closures of regular conjugacy classes. We prove that in arbitrary G such a cross-section exists if and only if the universal covering isogeny Ĝ → G is bijective; this answers Grothendieck's question cited in the epigraph. In particular, for char k = 0, the converse to Steinberg's theorem holds. The existence of a cross-section in G implies, at least for char k = 0, that the algebra k[G]G of class functions on G is generated by rk G elements. We describe, for arbitrary G, a minimal generating set of k[G]G and that of the representation ring of G and answer two Grothendieck's questions on constructing generating sets of k[G]G. We prove the existence of a rational (i.e., local) section of the quotient morphism for arbitrary G and the existence of a rational cross-section in G (for char k = 0, this has been proved earlier); this answers the other question cited in the epigraph. We also prove that the existence of a rational section is equivalent to the existence of a rational W-equivariant map T- - - >G/T where T is a maximal torus of G and W the Weyl group.