BBN Technologies

About: BBN Technologies is a based out in . It is known for research contribution in the topics: Noise & Network packet. The organization has 1725 authors who have published 3199 publications receiving 158589 citations.

A spreading-activation theory of semantic processing

Abstract: This paper presents a spreading-acti vation theory of human semantic processing, which can be applied to a wide range of recent experimental results The theory is based on Quillian's theory of semantic memory search and semantic preparation, or priming In conjunction with this, several of the miscondeptions concerning Qullian's theory are discussed A number of additional assumptions are proposed for his theory in order to apply it to recent experiments The present paper shows how the extended theory can account for results of several production experiments by Loftus, Juola and Atkinson's multiple-category experiment, Conrad's sentence-verification experiments, and several categorization experiments on the effect of semantic relatedness and typicality by Holyoak and Glass, Rips, Shoben, and Smith, and Rosch The paper also provides a critique of the Smith, Shoben, and Rips model for categorization judgments Some years ago, Quillian1 (1962, 1967) proposed a spreading-acti vation theory of human semantic processing that he tried to implement in computer simulations of memory search (Quillian, 1966) and comprehension (Quillian, 1969) The theory viewed memory search as activation spreading from two or more concept nodes in a semantic network until an intersection was found The effects of preparation (or priming) in semantic memory were also explained in terms of spreading activation from the node of the primed concept Rather than a theory to explain data, it was a theory designed to show how to build human semantic structure and processing into a computer

Beginning to read : thinking and learning about print

Abstract: "Beginning to Read reconciles the debate that has divided theorists for decades over what is the "right" way to help children learn to read Drawing on a rich array of research on the nature and development of reading proficiency, Marilyn Adams shows educators that they need not remain trapped in the phonics versus teaching-formeaning dilemma and offers instructional alternatives She proposes that phonies can work together with the "whole language" approach to teaching reading and provides an integrated treatment of the knowledge and processes involved in skillful reading, the issues surrounding their acquisition, and the implications for reading instruction Broad in scope and clearly written, "Beginning to Read provides fresh insights into the relationship between thinking and learning Developing the new connectionist theory as it relates to reading and its acquisition, Adams underscores the automatic nature of print perception in skillful readers while contrasting it with the attentive thought required for conceptual learning and understanding Adams reviews the history of debate over approaches to reading instruction as well as the research on their effectiveness, She consistently integrates instructional concerns with meticulous attention to research and theory from education, developmental and cognitive psychology, and linguistics Throughout, she emphasizes the interdependence of meaning appreciation and orthographic facility in both fluent reading and its acquisition Relevant learning theory is presented along with discussion of the roles of experience, practice, direct instruction, rules, thinking and understanding Adams stresses the importance of preschool language andliteracy experiences and includes descriptions of those that will best prepare children for reading instruction Marilyn Jager Adams is a Senior Scientist at Bolt Beranek and Newman Inc She was Principal Author and Curriculum Coordinator/Editor for the five volume classroom instruction series, "Odyssey: A Curriculum for Thinking Beginning to Read was developed in conjunction with the Reading Research and Education Center at the University of Illinois at Urbana-Champaign Learning, Development, and Conceptual Change series

Linear prediction: A tutorial review

Abstract: This paper gives an exposition of linear prediction in the analysis of discrete signals The signal is modeled as a linear combination of its past values and present and past values of a hypothetical input to a system whose output is the given signal In the frequency domain, this is equivalent to modeling the signal spectrum by a pole-zero spectrum The major part of the paper is devoted to all-pole models The model parameters are obtained by a least squares analysis in the time domain Two methods result, depending on whether the signal is assumed to be stationary or nonstationary The same results are then derived in the frequency domain The resulting spectral matching formulation allows for the modeling of selected portions of a spectrum, for arbitrary spectral shaping in the frequency domain, and for the modeling of continuous as well as discrete spectra This also leads to a discussion of the advantages and disadvantages of the least squares error criterion A spectral interpretation is given to the normalized minimum prediction error Applications of the normalized error are given, including the determination of an "optimal" number of poles The use of linear prediction in data compression is reviewed For purposes of transmission, particular attention is given to the quantization and encoding of the reflection (or partial correlation) coefficients Finally, a brief introduction to pole-zero modeling is given

DAML-S: semantic markup for web services

Abstract: The Semantic Web should enable greater access not only to content but also to services on the Web. Users and software agents should be able to discover, invoke, compose, and monitor Web resources offering particular services and having particular properties. As part of the DARPA Agent Markup Language program, we have begun to develop an ontology of services, called DAML-S, that will make these functionalities possible. In this paper we describe the overall structure of the ontology, the service profile for advertising services, and the process model for the detailed description of the operation of services. We also compare DAML-S with several industry efforts to define standards for characterizing services on the Web.