Motivation-based selection of negotiation partners

Negotiation is key to resolving conflicts, allocating resources and establishing cooperation in systems of self interested agents. Often, an agent may have to select between different potential negotiation partners, and identifying which offers the best chance of a successful negotiation is a challenging task. However, poor selection of partners can result in failure or in inefficient outcomes. To that end, this paper describes a motivation-based mechanism to evaluate and select between negotiation candidates. This is achieved by a twofold process: first, acceptable candidates are identified using motivation-based thresholds on objective scoring measures; second, the importance of issues is considered, and expected performance measures are evaluated accordingly. The mechanism is described and empirically evaluated

Negotiation in Multi-Agent Systems

In systems composed of multiple autonomous agents, negotiation is a key form of interaction that enables groups of agents to arrive at a mutual agreement regarding some belief, goal or plan, for example. Particularly because the agents are autonomous and cannot be assumed to be benevolent, agents must influence others to convince them to act in certain ways, and negotiation is thus critical for managing such inter-agent dependencies. The process of negotiation may be of many different forms, such as auctions, protocols in the style of the contract net, and argumentation, but it is unclear just how sophisticated the agents or the protocols for interaction must be for successful negotiation in different contexts. All these issues were raised in the panel session on negotiation

Normative agent reasoning in dynamic societies

Several innovative software applications such as those required by ambient intelligence, the semantic grid, e-commerce and e-marketing, can be viewed as open societies of heterogeneous and self-interested agents in which social order is achieved through norms. For agents to participate in these kinds of societies, it is enough that they are able to represent and fulfill norms, and to recognise the authority of certain agents. However, to voluntarily be part of a society or to voluntarily leave it, other characteristics of agents are needed. To find these characteristics we observe that on the one hand, autonomous agents have their own goals and, sometimes, they act on behalf of others whose goals must be satisfied. On the other, we observe that by being members, agents must comply with some norms that can be in clear conflict with their goals. Consequently, agents must evaluate the positive or negative effects of norms on their goals before making a decision concerning their social behaviour. Providing a model of autonomous agents that undertake this kind of norm reasoning is the aim of this paper

General relativity on a null surface: Hamiltonian formulation in the teleparallel geometry

The Hamiltonian formulation of general relativity on a null surface is established in the teleparallel geometry. No particular gauge conditons on the tetrads are imposed, such as the time gauge condition. By means of a 3+1 decomposition the resulting Hamiltonian arises as a completely constrained system. However, it is structurally different from the the standard Arnowitt-Deser-Misner (ADM) type formulation. In this geometrical framework the basic field quantities are tetrads that transform under the global SO(3,1) and the torsion tensor.Comment: 15 pages, Latex, no figures, to appear in the Gen. Rel. Gra

Asymptotically Non-Static Kerr-deSitter Spacetime With No Event Horizon

We present our derivations for Kerr-deSitter metric in a proper comoving coordinate system.It asymptotically approaches to the deSitter metric in Robertson-walker form.This has been done by considring the stationary axially-symmetric spacetime in which motion of particle is integrable.That is the Hamilton-Jacobi and Klein-Gordon equations are separable.In this form it is asymptotically consistent with comoving frame.Comment: Title changed,revised arguments,results unchanged

The intelligent street: responsive sound environments for social interaction

The Intelligent Street is a music installation that is able to respond intelligently to the collective requests of users interacting together. The performance it creates is largely influenced by the collective set of text commands from users' mobile phones. In this way, users in shared environments, subjugated for so long to uncontrollable and often undesired 'Muzak', can now directly influence their sonic environment and collectively create the aural soundscape that they desire. We see our project as enabling inhabitants of any given space from passive consumers to active creators, and anticipate it has significant commercial, social and educational potential.In this paper we present a description of the installation, its software architecture and implementation, as well as a report on subsequent user-evaluation in providing a musical public playground and, moreover, our over-arching goals as musicians and software engineers

Splines Parameterization of Planar Domains by Physics-Informed Neural Networks

The generation of structured grids on bounded domains is a crucial issue in the development of numerical models for solving differential problems. In particular, the representation of the given computational domain through a regular parameterization allows us to define a univalent mapping, which can be computed as the solution of an elliptic problem, equipped with suitable Dirichlet boundary conditions. In recent years, Physics-Informed Neural Networks (PINNs) have been proved to be a powerful tool to compute the solution of Partial Differential Equations (PDEs) replacing standard numerical models, based on Finite Element Methods and Finite Differences, with deep neural networks; PINNs can be used for predicting the values on simulation grids of different resolutions without the need to be retrained. In this work, we exploit the PINN model in order to solve the PDE associated to the differential problem of the parameterization on both convex and non-convex planar domains, for which the describing PDE is known. The final continuous model is then provided by applying a Hermite type quasi-interpolation operator, which can guarantee the desired smoothness of the sought parameterization. Finally, some numerical examples are presented, which show that the PINNs-based approach is robust. Indeed, the produced mapping does not exhibit folding or self-intersection at the interior of the domain and, also, for highly non convex shapes, despite few faulty points near the boundaries, has better shape-measures, e.g., lower values of the Winslow functional

Singularity in Gravitational Collapse of Plane Symmetric Charged Vaidya Spacetime

We study the final outcome of gravitational collapse resulting from the plane symmetric charged Vaidya spacetime. Using the field equations, we show that the weak energy condition is always satisfied by collapsing fluid. It is found that the singularity formed is naked. The strength of singularity is also investigated by using Nolan's method. This turns out to be a strong curvature singularity in Tipler's sense and hence provides a counter example to the cosmic censorship hypothesis.Comment: 8 pages, accepted for publication in Mod. Phys. Lett

Non-linear instability of Kerr-type Cauchy horizons

Using the general solution to the Einstein equations on intersecting null surfaces developed by Hayward, we investigate the non-linear instability of the Cauchy horizon inside a realistic black hole. Making a minimal assumption about the free gravitational data allows us to solve the field equations along a null surface crossing the Cauchy Horizon. As in the spherical case, the results indicate that a diverging influx of gravitational energy, in concert with an outflux across the CH, is responsible for the singularity. The spacetime is asymptotically Petrov type N, the same algebraic type as a gravitational shock wave. Implications for the continuation of spacetime through the singularity are briefly discussed.Comment: 11 pages RevTeX, two postscript figures included using epsf.st

A benchmark study on the model-based estimation of the go-kart side-slip angle

Nowadays, the active safety systems that control the dynamics of passenger cars usually rely on real-time monitoring of vehicle side-slip angle (VSA). The VSA can’t be measured directly on the production vehicles since it requires the employment of high-end and expensive instrumentation. To realiably overcome the VSA estimation problem, different model-based techniques can be adopted. The aim of this work is to compare the performance of different model-based state estimators, evaluating both the estimation accuracy and the computational cost, required by each algorithm. To this purpose Extended Kalman Filters, Unscented Kalman Filters and Particle Filters have been implemented for the vehicle system under analysis. The physical representation of the process is represented by a single-track vehicle model adopting a simplified Pacejka tyre model. The results numerical results are then compared to the experimental data acquired within a specifically designed testing campaign, able to explore the entire vehicle dynamic range. To this aim an electric go-kart has been employed as a vehicle, equipped with steering wheel encoder, wheels angular speed encoder and IMU, while an S-motion has been adopted for the measurement of the experimental VSA quantity