E1AR0002@SMUVM1.BITNET (10/31/86)
TECHNICAL NOTE: 121\hfill PRICE: \$20.00\\[0.01in] \noindent TITLE: MSYS: A SYSTEM FOR REASONING ABOUT SCENES\\ AUTHORS: HARRY G. BARROW and J. MARTIN TENENBAUM\\ DATE: APRIL 1976\\[0.01in] ABSTRACT: MSYS is a system for reasoning with uncertain information and inexact rules of inference. Its major application, to date, has been to the interpretation of visual features (such as regions) in scene analysis. In this application, features are assigned sets of possible interpretations with associated likelihoods based on local attributes (e.g., color, size, and shape). Interpretations are related by rules of inference that adjust the likelihoods up or down in accordance with interpretation likelihoods of related features. An asynchronous relaxation process repeatedly applies the rules until a consistent set of likelihood values is attained. At this point, several alternative interpretations still exist for each feature. One feature is chosen and the most likely of its alternatives is assumed. the rules are then used in this more precise context to determine likelihoods for the interpretations of remaining features by a further round of relaxation. The selection and relaxation steps are repeated until all features have been interpreted. Some interpretation typifies constraint optimization problems involving the assignment of values to a set of mutually constrained variables. For an interesting class of constraints, MSYS is guaranteed to find the optimal solution with less branching than conventional heuristic search methods. MSYS is implemented as a network of asynchronous parallel processes. The implementation provides an effective way of using data driven systems with distributed control for optimal stochastic search.\\ \pagebreak -------------------------------------------------------------------------------- -------------------------------------------------\\ TECHNICAL NOTE: 123\hfill PRICE: \$10.00\\[0.01in] \noindent TITLE: EXPERIMENTS IN INTERPRETATION-GUIDED SEGMENTATION\\ AUTHORS: J. MARTIN TENENBAUM and HARRY G. BARROW \\ DATE: MARCH 1976\\[0.01in] ABSTRACT: This paper presents a new approach for integrating the segmentation and interpretation phases of scene analysis. Knowledge from a variety of sources is used to make inferences about the interpretations of regions, and regions are merged in accordance with their possible interpretations. The deduction of region interpretations is performed using a generalization of Waltz's filtering algorithm. Deduction proceeds by eliminating possible region interpretations that are not consistent with any possible interpretation of an adjacent region. Different sources of knowledge are expressed uniformly as constraints on the possible interpretations of regions. Multiple sources of knowledge can thus be combined in a straightforward way such that incremental additions of knowledge (or equivalently, human guidance) will effect incremental improvements in performance. Experimental results are reported in three scene domains, landscapes, mechanical equipment, and rooms, using, respectively, a human collaborator, a geometric model and a set of relational constraints as sources of knowledge. These experiments demonstrate that segmentation is much improved when integrated computational overhead over unguided segmentation. Applications of the approach in cartography, photointerpretation, vehicle guidance, medicine, and motion picture analysis are suggested.\\ -------------------------------------------------------------------------------- -------------------------------------------------\\ \noindent TECHNICAL NOTE: 124\hfill PRICE: \$10.00\\[0.01in] \noindent TITLE: SUBJECTIVE BAYESIAN METHODS FOR RULE-BASED INFERENCE SYSTEMS\\ AUTHORS: RICHARD O. DUDA, PETER E. HART, and NILS J. NILSSON\\ DATE: JANUARY 1976\\[0.01in] ABSTRACT: The general problem of drawing inferences from uncertain or incomplete evidence has invited a variety of technical approaches, some mathematically rigorous and some largely informal and intuitive. Most current inference systems in artificial intelligence have emphasized intuitive methods, because the absence of adequate statistical samples forces a reliance on the subjective judgment of human experts. We describe in this paper a subjective Bayesian inference method that realizes some of the advantages of both formal and informal approaches. Of particular interest are the modifications needed to deal with the inconsistencies usually found in collections of subjective statements.\\ -------------------------------------------------------------------------------- -------------------------------------------------\\ TECHNICAL NOTE: 127\hfill PRICE: \$10.00\\[0.01in] \begin{tabbing} \noindent TITLE: \= APPLICATION OF INTERACTIVE SCENE ANALYSIS TECHNIQUES\\ \> TO CARTOGRAPHY\\ AUTHORS: THOMAS D. GARVEY and J. MARTIN TENENBAUM\\ DATE: SEPTEMBER 1976\\[0.01in] \end{tabbing} ABSTRACT: One of the most time-consuming and labor-intensive steps in map production involves the delineation of cartographic and cultural features such as lakes, rivers, roads, and drainages in aerial photographs. These features are usually traced manually on a digitizing table in painstaking detail. This paper investigates an alternative approach, an interactive graphically designates a feature of interest by pointing at or crudely tracing it with a display cursor. Using this input as a guide, the system employs context-dependent, scene-analysis techniques to extract a detailed outline of the feature. The results are displayed so that errors can be corrected by further interaction, for example, by tracing small sections of the boundary in detail. This interactive approach appears applicable to many other problem domains involving large quantities of graphic or pictorial data, which are difficult to extract in digital form by either strictly manual or strictly automatic means.\\ -------------------------------------------------------------------------------- -------------------------------------------------\\ TECHNICAL NOTE: 132\hfill PRICE: \$10.00\\[-0.15in] \begin{tabbing} \noindent TITLE: \= IS SOMETIME SOMETIMES BETTER THAN ALWAYS?\\ \> INTERMITTENT ASSERTION IN PROVING PROGRAM CORRECTNESS\\ AUTHORS: ZOHAR MANNA and RICHARD WALDINGER\\ DATE: JUNE 1976\\[-0.15in] \end{tabbing} ABSTRACT: This paper explores a technique for proving the correctness and termination of programs simultaneously. This approach, which we call the intermittent-assertion method, involves documenting the program with assertions that must be true at some time when control is passing through the corresponding point, but that need not be true every time. The method, introduced by Knuth and further developed by Burstall, promises to provide a valuable complement to the more conventional methods. We first introduce and illustrate the technique with a number of examples. We then show that a correctness proof using the invariant assertion method or the subgoal induction method can always be expressed using intermittent assertions instead, but that the reverse is not always the case. The method can also be used just to prove termination, and any proof of termination using the conventional well-founded sets approach can be rephrased as a proof using intermittent assertions. Finally, we show how the method can be applied to prove the validity of program transformations and the correctness of continuously operating programs.\\ -------------------------------------------------------------------------------- -------------------------------------------------\\ TECHNICAL NOTE: 134\hfill PRICE: \$10.00\\[0.01in] \noindent TITLE: EXPERIMENTS IN SPEECH UNDERSTANDING SYSTEM CONTROL\\ AUTHOR: WILLIAM H. PAXTON\\ DATE: AUGUST 1976\\[0.01in] ABSTRACT: A series of experiments was performed concerning control strategies for a speech understanding system. The main experiment tested the effects on performance of four major choices: focus attention by inhibition or use an unbiased best-first method, island-drive or process left or right, use context checks in priority setting or do not, and map words all at once or map only as called for. Each combination of choices was tested with 60 simulated utterances of lengths varying from 0.8 to 2.3 seconds. The results include analysis of the effects and interactions of the design choices with respect to aspects of system performance such as overall sentence accuracy, processing time, and storage. Other experiments include tests of acoustic processing performance and a study of the effects of increased vocabulary and improved acoustic accuracy.\\ -------------------------------------------------------------------------------- -------------------------------------------------\\ TECHNICAL NOTE: 136\hfill PRICE: \$10.00\\[0.01in] \noindent TITLE: SEMANTIC NETWORK REPRESENTATION IN RULE BASED INFERENCE SYSTEM\\ AUTHOR: RICHARD O. DUDA\\ DATE: JANUARY 1977\\[0.01in] ABSTRACT: Rule-based inference systems allow judgmental knowledge about a specific problem domain to be represented as a collection of discrete rules. Each rule states that if certain premises are known, then certain conclusions can be inferred. An important design issue concerns the representational form for the premises and conclusions of the rules. We describe a rule-based system that uses a partitioned semantic network representation for the premises and conclusions. Several advantages can be cited for the semantic network representation. The most important of these concern the ability to represent subset and element taxonomic information, the ability to include the potential for smooth interface with natural language subsystems. This representation is being used in a system currently under development at SRI to aid a geologist in the evaluation of the mineral potential of exploration sites. The principles behind this system and its current implementation are described in the paper.\\ -------------------------------------------------------------------------------- -------------------------------------------------\\ TECHNICAL NOTE: 137\hfill PRICE: \$10.00\\[-0.15in] \begin{tabbing} \noindent TITLE: INTERACTIVE AIDS FOR CARTOGRAPHY AND PHOTO INTERPRETATION\\ AUTHORS: \= HARRY BARROW, THOMAS GARVEY, JAN KREMERS,\\ \> J. MARTIN TENENBAUM and HELEN C. WOLF\\ DATE: JANUARY 1977\\[-0.15in] \end{tabbing} ABSTRACT: This report covers the six-month period October 1975 to April 1976. In this report, the application areas of ARPA-supported Machine Vision work at SRI were changed to Cartography and Photointerpretation. This change entailed general familiarization with the new domains, exploration of their current practices and uses, and determination of outstanding problems. In addition, some preliminary tool-building and experimentation have been performed with a view to determining feasibility of various AI approaches to the identified problems. The work of this period resulted in the production and submission to ARPA of a proposal for research into Interactive Aids for Cartography and Photointerpretation. This report will not reiterate in detail the content of the proposal, but will refer the reader to it for further information.\\ -------------------------------------------------------------------------------- -------------------------------------------------\\ TECHNICAL NOTE: 138\hfill PRICE: \$15.00\\[-0.15in] \begin{tabbing} \noindent TITLE: \= LIFER MANUAL: A GUIDE TO BUILDING PRACTICAL\\ \> NATURAL LANGUAGE INTERFACE\\ AUTHOR: GARY G. HENDRIX\\ DATE: FEBRUARY 1977\\[-0.15in] \end{tabbing} ABSTRACT: This document describes an application-oriented system for creating natural language interfaces between existing computer programs (such as data base management systems) and casual users. The system is easy to use and flexible, offering a range of capabilities that support both simple and complex interfaces. This range of capabilities allows beginning interface builders to rapidly define worktable sublets of English and gives more advanced language definitions. The system includes an automatic mechanism for handling certain classes of elliptical (incomplete) inputs, a spelling corrector, a grammar editor, and a mechanism that allows even novices, through the use of paraphrase, to extend the language recognized by the system. Experience with the system has shown that for many applications, very practicable interfaces may be created in a few days.\\ -------------------------------------------------------------------------------- ------------------------------------------------\\ TECHNICAL NOTE: 139\hfill PRICE: \$10.00\\[0.01in] \noindent TITLE: HUMAN ENGINEERING FOR APPLIED NATURAL LANGUAGE PROCESSING\\ AUTHOR: GARY G. HENDRIX\\ DATE: MARCH 1977\\[0.01in] ABSTRACT: Human engineering features for enhancing the usability of practical natural language systems are described. Such features include spelling correction, processing of incomplete (elliptical) inputs, interrogation of the underlying language definition through English queries, and an ability for casual users to extend the language accepted by the system through the use of synonyms and paraphrases. All of the features described are incorporated in LIFER, an applications-oriented system for creating natural language interfaces between computer programs and casual users. LIFER's methods for realizing the more complex human engineering features are presented.\\ -------------------------------------------------------------------------------- ------------------------------------------------\\ TECHNICAL NOTE: 140\hfill PRICE: \$10.00\\[0.01in] \noindent TITLE: LANGUAGE ACCESS TO DISTRIBUTED DATA WITH ERROR RECOVERY\\ AUTHOR: EARL D. SACERDOTI\\ DATE: APRIL 1977\\[0.01in] ABSTRACT: This paper discusses an effort in the application of artificial intelligence to the access of data from a large, distributed data base over a computer network. A running system is described that provides access to multiple instances of a data base management system over the ARPANET in real time. The system accepts a rather wide range of appropriate queries to the data base management system to answer the question, determines on which machine to carry out the queries, establishes links to those machines over the ARPANET, monitors the prosecution of the queries and recovers from certain errors in execution, and prepares a relevant answer to the original question. In addition to the functional components that make up the demonstration system, equivalent functional components with higher levels of sophistication are discussed and proposed.\\ -------------------------------------------------------------------------------- ------------------------------------------------\\ TECHNICAL NOTE: 142\hfill PRICE: \$25.00\\[0.01in] \noindent TITLE: A FRAMEWORK FOR SPEECH UNDERSTANDING\\ AUTHOR: WILLIAM H. PAXTON\\ DATE: JUNE 1977\\[0.01in] ABSTRACT: This paper reports the author's results in designing, implementing, and testing a framework for a speech-understanding system. The work was done as part of a multi-disciplinary effort based on state-of-the-art advances in computational linguistics, artificial intelligence, systems programming, and speech science. The overall project goal was to develop one or more computer systems that would recognize continuous speech uttered in the context or some well-specifiedtask by making extensive use of grammatical, semantic, and and contextual constraints. We call a system emphasizing such linguistic constraints a `speech-understanding system' to distinguish it from speech-recognition systems which rely on acoustic information alone. Two major aspects of a framework for speech understanding are integration of the process of forming a unified system out of the collection of components--and control--the dynamic direction of the overall activity of the system during the processing of an input utterance. Our method of system integration gives a central role to the input-language definition, which is based on augmented phrase- structure rules. A rule consists of a phrase-structure declaration which specifies the possible for computing 'attributes'and `factors.' Attribute statements determine the properties of particular phrases constructed by the rule; factor statements make acceptability judgments on phrases. Together these statements contain specifications for most of the potential interactions among system components. Our approach to system control centers on a system `Executive' applying the rules of the language definition organizing hypotheses and results, and assigning priorities. Phrases with their attributes and factors are the basic entities manipulated by the Executive, which takes on the role of a parser in carrying out its integration and control functions. The Executive controls the overall activity of the system by setting priorities on the basis of acoustics and linguistic acceptability judgments. These data are combined to form scores and ratings. A phrase score reflects a quality judgment independent of the phrase's context and gives useful local information concerning the sentential context. To get early and efficient access to the contextual information, we have developed a technique for calculating phrase ratings by a heuristic search of possible interpretations that would use the phrase. One of our experiments shows that this context-checking method results in significant improvements in system performance.\\ -------------------------------------------------------------------------------- ------------------------------------------------\\ TECHNICAL NOTE: 145\hfill PRICE: \$10.00\\[0.01in] \noindent TITLE: IDA\\ AUTHOR: DANIEL SAGALOWICZ\\ DATE: JUNE 1977\\[0.01in] ABSTRACT: IDA was developed at SRI to allow a casual user to retrieve information from a data base, knowing the fields present in the data base, but not the structure of the data base itself. IDA is part of a system that allows the user to express queries in a restricted subset of English, about a data base of fourteen files stored on CCA's Datacomputer. IDA's input is a very simple, formal query language which is essentially a list of restrictions on fields and queries about fields, with no mention of the structure of the data base. It produces a series of DBMS queries, which are transmitted over the ARPA network. The results of these queries are combined by IDA to provide the answer to the user's query. In this paper, we will define the input language, and give examples of IDA's behavior. We will also present our representation of the structural schema," which is the information needed by IDA to know how the data base is actually organized. We will give an idea of some of the heuristics which are used to produce a program in the language of the DBMS. Finally, we will discuss the limitations of this approach, as well as future research areas.\\ -------------------------------------------------------------------------------- -------------------------------------------------\\ -------