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AAAI News

AI Magazine

The Twenty-Sixth Annual Conference on Innovative Applications of Artificial Intelligence (IAAI-14) will focus on successful applications of AI technology.


Virtual Humans for Learning

AI Magazine

Virtual humans are computer-generated characters designed to look and behave like real people. Studies have shown that virtual humans can mimic many of the social effects that one finds in human-human interactions such as creating rapport, and people respond to virtual humans in ways that are similar to how they respond to real people. We believe that virtual humans represent a new metaphor for interacting with computers, one in which working with a computer becomes much like interacting with a person and this can bring social elements to the interaction that are not easily supported with conventional interfaces. We present two systems that embody these ideas. The first, the Twins are virtual docents in the Museum of Science, Boston, designed to engage visitors and raise their awareness and knowledge of science. The second SimCoach, uses an empathetic virtual human to provide veterans and their families with information about PTSD and depression.


The Sparse Principal Component of a Constant-rank Matrix

arXiv.org Machine Learning

The computation of the sparse principal component of a matrix is equivalent to the identification of its principal submatrix with the largest maximum eigenvalue. Finding this optimal submatrix is what renders the problem ${\mathcal{NP}}$-hard. In this work, we prove that, if the matrix is positive semidefinite and its rank is constant, then its sparse principal component is polynomially computable. Our proof utilizes the auxiliary unit vector technique that has been recently developed to identify problems that are polynomially solvable. Moreover, we use this technique to design an algorithm which, for any sparsity value, computes the sparse principal component with complexity ${\mathcal O}\left(N^{D+1}\right)$, where $N$ and $D$ are the matrix size and rank, respectively. Our algorithm is fully parallelizable and memory efficient.



On-Line Reconfigurable Machines

AI Magazine

We believe that these goals can be attained through the use of a very high level of modularity, both in hardware and software, combined with intelligent software. To test this hypothesis, Palo Alto Research Center (PARC) designed and built a prototype highly modular system in the printing domain. This "hypermodular" printer explores the extremes of modularity, reconfigurability, and parallelism in both hardware and software. The hardware prototype connects four standard Xerox marking engines (the component of a printer that does the actual printing) in parallel using a highly modular paper path. This configuration can achieve a print rate of four times that of an individual print engine. Reconfigurable manufacturing systems supports flexibility in configuration, graceful degradation (RMSs) were introduced as a concept in the late under component failure, and rerouting of inprocess 1990s (Koren et al. 1999), but the prerequisites, in sheets under exception conditions. These both software and hardware, for implementing them capabilities were made possible by utilizing advanced successfully have proved daunting; very few examples AI techniques in model-based planning, scheduling, of RMSs exist today in practice. These prerequisites search, and temporal reasoning such as state-space include modular, reconfigurable hardware components regression planning, partial-order scheduling, temporal as well as the software and control planning graph-based heuristic estimates, multiobjective architectures and logic to support them. RMSs can search, and fast, simple temporal network include both hard reconfigurability (physical reconfiguration) reasoning. The AI planner / scheduler incorporates and soft reconfigurability (logical reconfiguration) mostly domain-independent techniques from the (ElMaraghy 2006). This latter concept planning and scheduling research community, includes the idea of flexible routing as well as replanning enabling its flexibility and configurability to be and rescheduling.


Invited Talks

AAAI Conferences

Most approaches to semantics in computational linguistics represent meaning in terms of words or abstract symbols. Grounded-language research bases the meaning of natural language on perception and/or action in the (real or virtual) world. Machine learning has become the most effective approach to constructing natural-language systems; however, current methods require a great deal of laboriously annotated training data. Ideally, a computer would be able to acquire language like a child, by being exposed to language in the context of a relevant but ambiguous environment, thereby grounding its learning in perception and action. We will review recent research in grounded language learning and discuss future directions.


A Virtual Archive for the History of AI

AI Magazine

Publications that have influenced the growth of artificial intelligence are often difficult to obtain.ย  We first collected titles of several thousand publications from many well-known sources and then selected about 1850 titles considered to be especially influential.ย  We have identified, and in a few cases created, online versions of about half of these โ€œclassics in AI.โ€ย  Searchable text of the documents enables additional analysis of trends and influences.ย  Integration into the rest of the AITopics information portal contextualizes the classic publications.


A Concise Introduction to Models and Methods for Automated Planning

Morgan & Claypool Publishers

Planning is the model-based approach to autonomous behavior where the agent behavior is derived automatically from a model of the actions, sensors, and goals. The main challenges in planning are computational as all models, whether featuring uncertainty and feedback or not, are intractable in the worst case when represented in compact form. In this book, we look at a variety of models used in AI planning, and at the methods that have been developed for solving them. The goal is to provide a modern and coherent view of planning that is precise, concise, and mostly self-contained, without being shallow. For this, we make no attempt at covering the whole variety of planning approaches, ideas, and applications, and focus on the essentials.


Spherical perceptron as a storage memory with limited errors

arXiv.org Machine Learning

It has been known for a long time that the classical spherical perceptrons can be used as storage memories. Seminal work of Gardner, \cite{Gar88}, started an analytical study of perceptrons storage abilities. Many of the Gardner's predictions obtained through statistical mechanics tools have been rigorously justified. Among the most important ones are of course the storage capacities. The first rigorous confirmations were obtained in \cite{SchTir02,SchTir03} for the storage capacity of the so-called positive spherical perceptron. These were later reestablished in \cite{TalBook} and a bit more recently in \cite{StojnicGardGen13}. In this paper we consider a variant of the spherical perceptron that operates as a storage memory but allows for a certain fraction of errors. In Gardner's original work the statistical mechanics predictions in this directions were presented sa well. Here, through a mathematically rigorous analysis, we confirm that the Gardner's predictions in this direction are in fact provable upper bounds on the true values of the storage capacity. Moreover, we then present a mechanism that can be used to lower these bounds. Numerical results that we present indicate that the Garnder's storage capacity predictions may, in a fairly wide range of parameters, be not that far away from the true values.


AAAI News

AI Magazine

The deadline for the discounted AAAI rate is June AAAI-13 invites short papers on latebreaking for volunteer applications is May 1, 19, 2013. A special student rate has al-developments in the field of 2013.