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Beating a Defender in Robotic Soccer: Memory-Based Learning of a Continuous Function

Neural Information Processing Systems

Our research works towards this broad goal from a Machine Learning perspective. We are particularly interested in investigating how an intelligent agentcan choose an action in an adversarial environment. We assume that the agent has a specific goal to achieve. We conduct this investigation in a framework whereteams of agents compete in a game of robotic soccer. The real system of model cars remotely controlled from off-board computers is under development.


Dynamics of Attention as Near Saddle-Node Bifurcation Behavior

Neural Information Processing Systems

Most studies of attention have focused on the selection process of incoming sensory cues (Posner et al., 1980; Koch et al., 1985; Desimone et al., 1995). Emphasis was placed on the phenomena of causing different percepts for the same sensory stimuli. However, the selection of sensory input itself is not the final goal of attention. We consider attention as a means for goal-directed behavior and survival of the animal. In this view, dynamical properties of attention are crucial. While attention has to be maintained long enough to enable robust response to sensory input, it also has to be shifted quickly to a novel cue that is potentially important. Long-term maintenance and quick transition are critical requirements for attention dynamics.


Modern Analytic Techniques to Solve the Dynamics of Recurrent Neural Networks

Neural Information Processing Systems

We describe the use of modern analytical techniques in solving the dynamics of symmetric and nonsymmetric recurrent neural networks nearsaturation. These explicitly take into account the correlations betweenthe post-synaptic potentials, and thereby allow for a reliable prediction of transients. 1 INTRODUCTION Recurrent neural networks have been rather popular in the physics community, because they lend themselves so naturally to analysis with tools from equilibrium statistical mechanics. This was the main theme of physicists between, say, 1985 and 1990. Less familiar to the neural network community is a subsequent wave of theoretical physical studies, dealing with the dynamics of symmetric and nonsymmetric recurrentnetworks. The strategy here is to try to describe the processes at a reduced level of an appropriate small set of dynamic macroscopic observables.


Temporal coding in the sub-millisecond range: Model of barn owl auditory pathway

Neural Information Processing Systems

Binaural coincidence detection is essential for the localization of external sounds and requires auditory signal processing with high temporal precision. We present an integrate-and-fire model of spike processing in the auditory pathway of the barn owl. It is shown that a temporal precision in the microsecond range can be achieved with neuronal time constants which are at least one magnitude longer. An important feature of our model is an unsupervised Hebbian learning rule which leads to a temporal fine tuning of the neuronal connections.


Human Reading and the Curse of Dimensionality

Neural Information Processing Systems

Whereas optical character recognition (OCR) systems learn to classify singlecharacters; people learn to classify long character strings in parallel, within a single fixation. This difference is surprising because high dimensionality is associated with poor classification learning. This paper suggests that the human reading system avoids these problems because the number of to-be-classified images isreduced by consistent and optimal eye fixation positions, and by character sequence regularities. An interesting difference exists between human reading and optical character recognition (OCR)systems. The input/output dimensionality of character classification in human reading is much greater than that for OCR systems (see Figure 1) . OCR systems classify one character at time; while the human reading system classifies as many as 8-13 characters per eye fixation (Rayner, 1979) and within a fixation, character category and sequence information is extracted in parallel (Blanchard, McConkie, Zola, and Wolverton, 1984; Reicher, 1969).


Stochastic Hillclimbing as a Baseline Method for Evaluating Genetic Algorithms

Neural Information Processing Systems

We investigate the effectiveness of stochastic hillclimbing as a baseline for the performance of genetic algorithms (GAs) as combinatorialevaluating In particular, we address two problems to whichfunction optimizers.


Using Artificial Neural Networks to Predict the Quality and Performance of Oil-Field Cements

AI Magazine

Inherent batch-to-batch variability, aging, and contamination are major factors contributing to variability in oil-field cement-slurry performance. Such variability imposes a heavy burden on performance testing and is often a major factor in operational failure. Our approach involves predicting cement compositions, particle-size distributions, and thickening-time curves from the diffuse reflectance infrared Fourier transform spectrum of neat cement powders. Our research shows that many key cement properties are captured within the Fourier transform infrared spectra of cement powders and can be predicted from these spectra using suitable neural network techniques.


Diagnosing Delivery Problems in the White House Information-Distribution System

AI Magazine

As part of a collaboration with the White House Office of Media Affairs, members of the Artificial Intelligence Laboratory at the Massachusetts Institute of Technology designed a system, called COMLINK, that distributes a daily stream of documents released by the Office of Media Affairs. Approximately 4,000 direct subscribers receive information from this service, but more than 100,000 people receive the information through redistribution channels. The information is distributed through e-mail and the World Wide Web. These invalid subscriptions cause a backwash of hundreds of bounced-mail messages each day that must be processed by the operators of the COMLINK system.


Intelligent Retail Logistics Scheduling

AI Magazine

The supply-chain integrated ordering network (SCION) depot-bookings system automates the planning and scheduling of perishable and nonperishable commodities and the vehicles that carry them into J. This initiative is strategic, enabling the business to make the key move from weekly to daily ordering. The system leverages AI techniques to provide a business solution that meets challenging functional and performance needs. The SCION depot-bookings system is operational, providing schedules for 22 depots across the United Kingdom.