Journal of Intelligent & Fuzzy Systems - Volume 18, issue 3

Authors: Nissan, Ephraim

Article Type: Research Article

Citation: Journal of Intelligent & Fuzzy Systems, vol. 18, no. 3, pp. 211-215, 2007

Authors: Menegatti, E. | Simionato, C. | Tonello, S. | Cicirelli, G. | Distante, A. | Ishiguro, H. | Pagello, E.

Article Type: Research Article

Abstract: In this paper an omnidirectional Distributed Vision System (DVS) is presented. The presented DVS is able to learn to navigate a mobile robot in its working environment without any prior knowledge about calibration parameters of the cameras or the control law of the robot (this is an important feature if we want to apply this system to existing camera networks). The DVS consists of different Vision Agents (VAs) implemented by omnidirectional cameras. The main contribution of …the work is the explicit distribution of the acquired knowledge in the DVS. The aim is to develop a totally autonomous system able not only to learn control policies by on-line learning, but also to deal with a changing environment and to improve its performance during lifetime. Once an initial knowledge is acquired by one Vision Agent, this knowledge can be transferred to other Vision Agents in order to exploit what was already learned. In this paper, first we investigate how the Vision Agent learns the knowledge, then we evaluate its performance and test the knowledge propagation on three different VAs. Experiments are reported both using a system simulator and using a prototype of the Distributed Vision System in a real environment demonstrating the feasibility of the approach. Show more

Citation: Journal of Intelligent & Fuzzy Systems, vol. 18, no. 3, pp. 217-232, 2007

Authors: Caglioti, Vincenzo

Article Type: Research Article

Abstract: This paper addresses the self-localization of a mobile robot, equipped with a laser range scanner, navigating within a curvilinear environment. Specifically, we present a technique for updating a current pose estimate (e.g., deriving from dead-reckoning) by means of a single range measure. Current approaches to this problem, based on the Extended Kalman (EK) estimator, often yield unreliable results due to linearization errors, inherent in curvilinear environments. Therefore, a second-order method is proposed, in …which the measurement result is approximated in terms of a two-degree function of the pose estimate error (instead of a linear one). Experiments conducted on a real robot navigating within a curvilinear environment are reported, showing that the errors in the updated estimate, provided by the proposed method, are significantly lower than the errors in the EK estimate. Show more

Keywords: Mobile robots, self-localization, pose estimate updating, curvilinear environments, range measures, extended kalman filtering, nonlinear pose estimation

Citation: Journal of Intelligent & Fuzzy Systems, vol. 18, no. 3, pp. 233-244, 2007

Authors: Bonarini, Andrea | Matteucci, Matteo | Restelli, Marcello

Article Type: Research Article

Abstract: Robotic systems that carry out inferential activities over symbolic representations require a process that keeps a connection between physical objects and their symbolic image. Typically, this problem has been faced with ad-hoc solutions hardwired in the code. Recently, Coradeschi and Saffiotti have formalized this problem and they have called it anchoring. We propose a symbolic modelling approach to deal with the anchoring problem, in applications involving several embodied agents, by applying standard AI techniques. We …discuss how such a modelling approach supports the process of instantiation of concepts by aggregating percepts possibly affected by imprecision and uncertainty. Percepts may come from several sensors possibly distributed both in the environment and on several mobile agents. Furthermore, we show how a tracking model can be used to maintain the link between percepts and conceptual instances in time. This approach to the anchoring problem has been implemented in a software module called MAP (MAP Anchors Perceptions), that has been tested in a robotic soccer application. Show more

Citation: Journal of Intelligent & Fuzzy Systems, vol. 18, no. 3, pp. 245-254, 2007

Authors: Badaloni, S. | Falda and, M. | Giacomin, M.

Article Type: Research Article

Abstract: The satellite-scheduling problem represents an interesting field to test non-conventional temporal solvers because scheduling-problems are inherently over-constrained and, moreover, the tasks may be known in an imprecise and uncertain manner. In this paper we present an application of our fuzzy temporal reasoning system to the satellite-scheduling problem. First, we describe our model of integration of qualitative and quantitative temporal information affected by vagueness and uncertainty. Then, we show the usefulness of fuzzy …constraints when dealing with over-constrained temporal problems. Show more

Keywords: Fuzzy temporal reasoning, over-constrained problems

Citation: Journal of Intelligent & Fuzzy Systems, vol. 18, no. 3, pp. 255-265, 2007

Authors: Demir, Güleser K. | Gini, Maria

Article Type: Research Article

Abstract: We present a solution to the winner determination problem which takes into account not only costs but also risk aversion of the agent that accepts the bids, and which works for auctioning tasks that have time and precedence constraints. We use Expected Utility Theory as the basic mechanism for decision-making. Our theoretical and experimental analysis shows that Expected Utility is useful for choosing between cheap-but-risky and costly-but-safe bids. Moreover, we show how bids with similar costs …and similar probabilities of being successfully completed but different time windows can be efficiently selected or rejected. Show more

Keywords: Winner determination, risk, expected utility, automated auctions, multi-agent contracting

Citation: Journal of Intelligent & Fuzzy Systems, vol. 18, no. 3, pp. 267-280, 2007

Authors: Nissan, Ephraim

Article Type: Research Article

Abstract: In this sequence of two articles, a formal representation for legal or other narratives as previously introduced by myself [152,154-158,165] is augmented and integrated with a representation for arguments, and applied to the setting into formulae of a particular historical episode. Cognitive states are of interest, because one of the contenders in a war of succession is captured by deception by a would-be ally; they both had authority on other characters obeying their orders. …In the present Part I, we survey the state of the art of narrative representation and processing in artificial intelligence. As in this article we augment our method of representation with a data structure based on the structure of arguments, we shortly survey computational work on argumentation as well. We introduce the broader narrative, and the particular episode which we set in formulae in Part II. Formulae representing notions from the broader narrative, and in particular the circumstances which led to the war of succession, are presented in Part I. Special operators are defined, which arguably are relevant for a very large, pervasive array of narrative situations. Moreover, in Part I we introduce a Wigmorean representation. Show more

Citation: Journal of Intelligent & Fuzzy Systems, vol. 18, no. 3, pp. 281-306, 2007

Authors: Nissan, Ephraim

Article Type: Research Article

Abstract: In Part I, the background was introduced, for the formalism proposed in the present Part II. That background consists of: (a) an overview of the state of the art of representing or processing narratives within artificial intelligence, (b) the narrative of the succession war in the Mughal empire, which led to the reign of Aurangzeb, (c) the basics of our method of representation, (d) a survey of topics relevant to the latter, and in particular, of …computational work on argumentation. In the present Part II, we propose a formalism which captures how Aurangzeb managed to deceive and capture his brother Murad, who had been his ally in the succession war. Steps toward achieving Aurangzeb's goal of capturing him included: attracting Murad into Aurangzeb's camp, reducing his alertness by making him drink, having him sleep in a tent inside the camp, attracting Murad's bodyguard outside that tent and overpowering him, and then removing Murad's own weapons and binding Murad's feet in golden fetters. A formal representation for legal or other narratives as previously introduced by the present author [16-21,33] is augmented and integrated with a representation for arguments, and applied to the setting into formulae of the particular historical episode. Cognitive states are paramount, and so are perception and communications, as well as authority relations between characters. Show more

Keywords: Narrative, knowledge representation, deception in interaction, agents' beliefs, goals, and action, argumentation

Citation: Journal of Intelligent & Fuzzy Systems, vol. 18, no. 3, pp. 307-327, 2007