147 research outputs found
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
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 canât 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
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
- âŠ