LAWS@SRI-AI.ARPA (04/23/85)
From: AIList Moderator Kenneth Laws <AIList-REQUEST@SRI-AI> AIList Digest Tuesday, 23 Apr 1985 Volume 3 : Issue 50 Today's Topics: Administrivia - Lost Messages, Machine Translation - La Jolla, Application - AI in Agriculture, Seminars - Transformation of Functional Equations (MIT) & Programming with Recurrent Equations (Penn) & Representation, Aesthetics, Learnability (SU) & The MIT Mobile Robot Project (Penn) & ARLO: Representing Representation Language (MIT), Humor - Representation Lunches & The Traveling President Problem ---------------------------------------------------------------------- Date: Mon 22 Apr 85 20:44:07-PST From: Ken Laws <Laws@SRI-AI.ARPA> Reply-to: AIList-Request@SRI-AI.ARPA Subject: Lost Messages SRI-AI had a bad system crash Sunday morning; mail sent to AIList or AIList-Request that morning may not have gotten through. -- Ken Laws ------------------------------ Date: 19 APR 85 14:16-N From: PETITP%CGEUGE51.BITNET@WISCVM.ARPA Subject: Machine translation at La Jolla [In answer to request from goodhart@nosc AIList Digest v3 #46] Hi! The people you are looking for in La Jolla are probably working on SYSTRAN, a commercial machine translation system. Here is their address: P. Toma WTC Inc 7854 Ivanohe Avenue PO Box 907 La Jolla, Ca 92037 Tel: 619/459-3471 Other commercial systems I know of in the States are the Weidner System and the ALPS system, both companies are located in Provo, Utah. (I could get more for you if you are interested). But none of those are proper research projects, and are based on linguistically and computationnally "old" ideas. A more advanced project is METAL, developed at the Linguistic Research Center, University of Texas, in Austin. You can contact Rebecca Root (LRC.ROOT@UTEXAS.ARPA) to get more information about it. In Europe there are the SUSY project (Saarbruecken,Germany), and the GETA project (Grenoble, France), and the EUROTRA project of the European Economic Communities, to which many european universities collaborate. Here at ISSCO in Geneva we are working on EUROTRA. And of course there is many Japanese projects but I don't know much about them. A good introduction to machine translation is a paper by Jonathan Slocum, presented at COLING-84 in Stanford: "Machine Translation: its History, Current Status an Future Prospects". If you can't get a copy of the proceedings, I think it was also published as a report by the LRC in Austin. Last year ISSCO organised a tutorial on machine translation and a book will be published by Edinburgh University Press. Dominique Petitpierre (PETITP@CGEUGE51.BITNET) ISSCO 54 route des acacias CH-1227 GENEVA (Switzerland) ------------------------------ Date: Mon, 22 Apr 85 08:23 EST From: kyle.wbst@Xerox.ARPA Subject: Friedland's request about AI in agriculture Some years ago, Control Data Corp in Minneapolis had a New Business Ventures Unit that included various software systems for the farmer and Agribusiness industry. You might check with them to see what is going on in that area with them now. Also at about that same time frame they got on board a former SRI type who had background with SRI's early AI efforts. I don't know if there was any connection between that person and the farm stuff though. Earle Kyle. ------------------------------ Date: Tue,16 Apr 85 16:16:24 EST From: Robyn D. Spencer <TOOTSE@MIT-MC> Subject: Seminar - Transformation of Functional Equations (MIT) [Forwarded from the MIT bboard by Laws@SRI-AI.] DATE: April 22, 1985 TIME: Lecture 3:30 p.m. PLACE: NE43-3rd floor conference room TRANSFORMATIONS of HIGHER-TYPE FUNCTIONAL EQUATIONS VIA THE COMPUTATION OF RETRACTS Richard Statman Carnegie-Mellon University Functional equations occur in diverse branches of logic and computer science. In type theory with the axiom of choice, every formula is equivalent to one which asserts that a functional equation has a solution with the given parameters. In theorem proving, unification problems are simply functional equations which one wants to solve in all models. In programming language semantics, programming constructs, such as fixed point operators, are represented as solutions to functional equations. The general functional equation Fx=Gx where operators F,G have type A -> B can be transformed one with operators of type C -> D while preserving all solutions, when there is a surjective H of type C -> A and an injective J of type B -> D. The transformed equation is J(F(Hy))=J(G(Hy)) We shall show that this transformation can be carried out in every model if and only if A is a retract of C and B is a retract of D in every model. There is a retract from C onto A if and only if the equation lambda z. y(xz) = I is solvable for some y in C -> A and x in A -> C. This equation is solvable in every model if and only if it is solvable in the term model of beta-eta conversion. Thus transformations of the above type can always be carried out by lambda terms. We shall give some further information about when this type of transformation can be carried out including bounds on the size of A as a function of the size of C. The decision problem (unification problem) is open. HOST: Albert Meyer ------------------------------ Date: Wed, 17 Apr 85 21:06 EST From: Tim Finin <Tim%upenn.csnet@csnet-relay.arpa> Subject: Seminar - Programming with Recurrent Equations (Penn) PROGRAMMING WITH RECURRENT EQUATIONS Boleslaw Szymanski (University Pennsylvania) 3:00pm April 23, 1985, 216 Moore School, Univ. of Pennsylvania Software development tools proposed for new generation of computers are based on assertive programming, where a program is expressed as a set of assertions. There are two basic notations used in assertive programming: Horn clauses of logic programming (e.g. PROLOG) and conditional equations used in so called definitional or equational languages. Equational languages are natural and convenient complements of PROLOG-like languages for such applications as programming dataflow machines and modelling complex systems. This talk focuses on languages based on recurrent equations. Finite- difference approximations to systems of partial difference equations lead to such recurrence equations. Our experience indicates that such languages are general purpose. Description of many algorithms is greatly simplified when presented in such a form. The talk presents new results of the MODEL project. Three MODEL language processor components: Compiler, Configurator, and Timing System will be discussed. The emphasis will be on the following problems: 1) optimization of programs generated by the MODEL compiler, 2) programming parallel and/or distributed computations with Configurator 3) use of temporal relations for scheduling parallel components 4) distributed termination of a solution to simultaneous equations, 5) real-time software development using Timing System. Future research will also be outlined. ------------------------------ Date: Wed 17 Apr 85 17:11:18-PST From: Emma Pease <Emma@SU-CSLI.ARPA> Subject: Seminar - Representation, Aesthetics, Learnability (SU) [Excerpted from the CSLI Newsletter by Laws@SRI-AI.] CSLI ACTIVITIES FOR *NEXT* THURSDAY, April 25, 1985 4:15 p.m. CSLI Colloquium Redwood Hall ``The Representational Basis for Everyday Aesthetic Room G-19 Experience -- A Motivational Constraint on Learnable Systems of Knowledge'' Tom Bever, Columbia University and CASBS ``The Representational Basis for Everyday Aesthetic Experience -- A Motivational Constraint on Learnable Systems of Knowledge'' The structure of everyday aesthetic judgements depends on computations of mental representations and relations between representations. Examination of objects of everyday aesthetic preference (e.g., simple rhythms, shapes, and songs) affords a definition of the aesthetically satisfying experience: such experiences involve the formation of incompatible representations and their resolution within the framework of an overarching representational system. The enjoyment of such experiences follows from the extent to which they are like solving a problem during normal cognitive development. Indigenous systems like language must have formal properties that stimulate aesthetically satisfying experiences as an immediate motivation for the acquisition of abstract structures. That is, we learn a multi-levelled representational structure for language because it is fun. --Tom Bever ------------------------------ Date: Thu, 18 Apr 85 14:59 EST From: Tim Finin <Tim%upenn.csnet@csnet-relay.arpa> Subject: Seminar - The MIT Mobile Robot Project (Penn) THE MIT AI LAB MOBILE ROBOT PROJECT - Rodney A. Brooks (MIT) 3pm April 25, 23 Moore School, Univ. of Pennsylvania We are interested in a number of questions relating to intelligent mobile robots. These include the following. (a) How to combine a number of early vision modules into a robust vision system which can operate under a wide range of conditions and a wide range of scenes through redundancy of perceptions. (b) How to make reliable maps given that all sensors produce error laden readings, and control of the robot is also a source of error. (c) How to apply model-based vision techniques to the landmark selection and recognition problems. (d) How to make a robot control and planning system which is competent and robust enough to allow an autonomous vehicle to operate for long periods with absolutely no assistance from a human. In support of these goals we are building a mobile robot which will operate autonomously for a number of hours at a time within the Artificial Intelligence Laboratory office area. Our approach to building the robot and its controlling software differs from that used in many other projects in a number of ways. (1) We model the world as three dimensional rather than two. (2) We build no special environment for our robot and insist that it must operate in the same real world that we inhabit. (3) In order to adequatley deal with uncertainty of perception and control we build relational maps rather than maps embedded in a coordinate system, and we maintain explicit models of all uncertainties. (4) We explicitly monitor the computational performance of the components of the control system, in order to refine the design of a real time control system for mobile robots based on a special purpose distributed computation engine. (5) We use vision as our primary sense and relegate acoustic senors to local obstacle detection. (6) We use a new architecture for an intelligent system designed to provide integration of many early vision processes, and robust real-time performance even in cases of sensory overload, failure of certain early vision processes to deliver much information in particular situations, and computation module failure. ------------------------------ Date: 19 Apr 1985 15:57 EST (Fri) From: "Daniel S. Weld" <WELD%MIT-OZ@MIT-MC.ARPA> Subject: Seminar - ARLO: Representing Representation Language (MIT) [Forwarded from the MIT bboard by SASW@MIT-MC.] AI Revolving Seminar Ken Haase ARLO: Representing Representation Languages Tuesday, April 23; 4:00pm; 8th Floor Playroom ARLO is a language for describing the implementation and functionality of frame based representation languages. A given representation language is specified in ARLO by a collection of structures describing how its descriptions are interpreted, defaulted, and verified. This high level description is compiled into lisp code and ARLO structures whose interpretation fulfills the langauge's abstract specification. The dependencies of this compilation process (from description to implementation) are recorded by ARLO, so that changes in the high-level description will propogate to the generated implementation. In addition, ARLO itself --- as a representation language for expressing and compiling partial and complete language specifications --- is described and interpreted in the same manner as the languages it describes and implements. This talk will address general issues in the definition and implementation of representation language languages, as well as the technical problems in implementing self-descriptive systems. Finally, I will discuss the use of ARLO-like languages as a basis for learning and concept formation programs like Lenat's Eurisko. ------------------------------ Date: 11 Apr 1985 13:18 EST (Thu) From: Mike Gennert@MIT-OZ <MICHAELG%MIT-OZ@MIT-MC.ARPA> Subject: Representation Lunches [Forwarded from the MIT bboard by SASW@MIT-MC.] COMPUTER AIDED CONCEPTUAL ART (CACA) REVOLTING SEMINAR SERIES presents TACO: REPRESENTING REPRESENTATION LUNCHES Mike Gennert Mike Gerstenberger TACO is a lunch for describing the implementation and functionality of frame based representation lunches. A given representation lunch is specified in TACO by a collection of fillings describing how its descriptions are interpreted, defaulted, verified, and eaten. This high level description is compiled into TACO shell code and TACO fillings whose interpretation fulfills the langauge's nutritional specification. The dependencies of this compilation process (from description to implementation) are recorded by TACO, so that changes in the high-level description will propogate to the generated implementation. In addition, TACO itself --- as a representation lunch for expressing and compiling partial and complete lunch specifications --- is devoured and interpreted in the same manner as the lunches it devoured and implements, i.e., with one's fingers. This talk will address general issues in the definition and implementation of representation lunch lunches, as well as the technical problems in implementing self-devouring systems. Finally, We will discuss the use of TACO-like lunches as a basis for learning and concept formation programs like Automatic Hairstyle Generation: The Further Adventures of Eurisko. Friday, April 12, 12:00, 3rd Floor Lounge ------------------------------ Date: Thu, 18 Apr 85 17:26:10 est From: Walter Hamscher <hamscher at mit-htvax> Subject: The Traveling President Problem [Forwarded from the MIT bboard by SASW@MIT-MC.] COMPUTER AIDED CONCEPTUAL ART (CACA) REVOLTING SEMINAR SERIES :-) (-: THE TRAVELING PRESIDENT PROBLEM Tod Malmedy We present a new variation of the traveling salesman problem. There are two differences. First, the links are free but the nodes, representing memorials, have either small positive or large negative weights, and the goal is to maximize this weight. Second, unlike most problems, in which a solver is allowed to exaustively search the space of combinations for an optimal solution, in this variation the value of the final solution is penalized by the number of combinations tested before finding it. Under these conditions the L/D (Leave it to Deaver) strategy can be proven to be the worst possible. TIME: 12 Noon Friday PLACE: 3rd Floor Theory Playroom HOSTS: Bhaskar Ghudaroy and Mike Beckerle ------------------------------ End of AIList Digest ********************