Dept. of Computer and Information science, Linköping University
Last updated: Tue, 02 Dec 1997 11:02:09
Bäckström, C. (1988). Keeping and Forcing: How to Represent Cooperating Actions. Technical Report LiTH-IDA-R-88-05, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: This report presents a formalism for representing action structures, i.e. complex systems of actions going on in sequence or in parallel and possibly interfering or interacting with each other. The same formalism supports all kinds of reasoning about action structures like e.g. planning, plan projection and plan observation. Actions are characterized with five conditions expressing how they relate to the world and to other actions. It is possible to express not only when two actions are allowed to occur in parallel, but also when they are required to co-occur. Such synchronization is implicitly forced by the definitions of the actions. The conditions can also be used to implicitly define hierarchies of actions which can be used both downwards, for hierarchical planning, and upwards, for plan observation.
Bäckström, C. (1988). A Representation of Coordinated Actions Characterized by Interval Valued Conditions. Technical Report LiTH-IDA-R-88-06, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of ISMIS'88, Torino, Italy, 12-15 Oct. 1988. (bibtex),
Abstract: We introduce the concept of action structures as a set of actions together with information about their relative temporal ordering. Actions are characterized by pre- and post-conditions stating how they change the world. They are also characterized by prevail- and keep-conditions, stating what they require and cause, respectively, to hold during their execution. This way, the definition of actions can implicitly specify when actions are allowed to or have to occur in parallel. It is also possible to let the definition of an action implicitly specify the terminating condition for the action. The conditions used to characterize actions are expressed as partial world states. The main novelty of this report is that these partial world states can range over discrete domains as well as over interval valued domains.
Bonnier, S. and Maluszynski, J. (1988). Towards Clean Amalgamation of Logic Programs with External Procedures. Technical Report LiTH-IDA-R-88-03, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: The paper presents a clean approach to the amalgamation of logic programming with external functional procedures. Both the logical semantics and the operational semantics of the amalgamated language are outlined. The operational semantics is based on an incomplete E-unification algorithm which we call S-unification. It is suggested to use the abstract interpretation technique for identifying classes of goals for which the approach is complete. For this purpose a domain of abstract terms is defined, and an abstract unification algorithm used for a compile-time check is developed.
Dahlbäck, N. (1988). Mental Models and Text Understanding - a Commented Review. Technical Report LiTH-IDA-R-88-18, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: No abstract available
Drabent, W., Nadjm-Tehrani, S., and Maluszynski, J. (1988). Algorithmic Debugging with Assertions. Technical Report LiTH-IDA-R-88-04, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of META 88 - Workshop on Meta Programming in Logic Programming, Bristol, June 21-24, 1988. (bibtex),
Abstract: Algorithmic debugging, as presented by Shapiro, is an interactive process where the debugging system acquires knowledge about the expected behaviour of the debugged program and uses it to localize errors. This paper suggests a generalization of the language used to communicate with the debugger. In addition to the usual "yes" and "no" answers formal specifications of some properties of the intended model are allowed. The specifications are logic programs. They employ library procedures and are developed interactively in the debugging process. An experimental debugging system incorporating this idea has been implemented. In contrast to some other systems, its insufficiency diagnoser does not require instantiation of unsolved goals by the oracle. A formal proof of correctness and completeness of this algorithm is presented.
Fagerström, J. (1988). Design and Test of Distributed Applications. Technical Report LiTH-IDA-R-88-22, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of the International Conference on Software Engineering, ICSE, Singapore, April 1988. (bibtex),
Abstract: It is well known that programming and testing distributed systems can be extremely difficult. Reasons for this include non-deterministic behaviour, non-reproducibility of events, complex timing of events, and complex states. This paper presents a paradigm and a system that will support a programmer when designing, programming, and testing a distributed application. Our main point is that the structure introduced by the paradigm must be kept and exploited during design, programming, and testing. One is not helped by a programming method which introduces a structure just to break it down again. We have developed a structural model based on common structures in distributed systems. This structural model is used to describe the logical relationships between components in a system. It is also integrated into the programming environment.
Fagerström, J. and Larsson, Y. (1988). Two Contributions on Debugging Distributed System. Technical Report LiTH-IDA-R-88-23, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of ACM SIGPLAN/SIGOPS, Workshop on Parallel and Distributed Debugging. (bibtex),
Abstract: This report presents two extended abstract also published in a workshop on parallel and distributed debugging. The first by Johan Fagerström presents a general framework for distributed system design and testing. The second paper, by Yngve Larsson, presents ideas around a set of debug tools.
Fagerström, J. and Strömberg, L. (1988). A Paradigm for Distributed System Design and Test. Technical Report LiTH-IDA-R-88-21, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of COMPCON'SPRING 88, San Francisco, Feb.-March 1988. (bibtex),
Abstract: It is well known that programming and testing distributed systems can be extremely difficult. Reasons for this include non-deterministic behaviour, non-reproducibility of events, complex timing of events, and complex states. This paper presents a paradigm and a system that will support a programmer when designing, programming, and testing a distributed application. Our main point is that the structure introduced by the paradigm must be kept and exploited during design, programming, and testing. One is not helped by a programming method which introduces a structure just to break it down again. We have developed a structural model based on common structures in distributed systems. This structural model is used to describe the logical relationships between components in a system. It is also integrated into the programming environment.
Fritzson, P. (1988). Incremental Symbol Processing. Technical Report LiTH-IDA-R-88-09, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: This paper introduces a general entity-relational model for incremental symbol processing. Previous models have either been non-incremental, or if incremental they have usually been language-specific, or too simple to handle complex languages. This model forms the basis for the generation of efficient symbol processing mechanisms from high-level declarative specifications and query expressions, using program transformation techniques such as data type refinement.The model is conceptually simple, but powerful enough to model languages of the complexity of Ada. The new model is compared to earlier, more restricted, incremental hierarchical symbol table models. The difference between incremental symbol processing and symbol processing in conventional compilers is also discussed in the paper.
Jönsson, A. and Dahlbäck, N. (1988). Talking to a computer is not like talking to your best friend. Technical Report LiTH-IDA-R-88-34, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of the First Scandinavian Conference on Artificial Intelligence, March 9-10, 1988, Tromsö, Norway. (bibtex),
Abstract: When developing natural language interfaces, it is important to know the characteristics of the language used. We have developed a set of tools for conducting human-computer natural language dialogue simulations (Wizard of Oz experiments) and for analyzing the data obtained. We report methods used and results obtained from a series of such experiments. The focus of the study was on occasional users and on the structure of the dialogue. Three different background systems were used; one database and two advisory systems of different complexity. The results point to the need for mechanisms for handling connected discourse in interfaces for this user group. They also indicate that there are different classes of dialogue situations requiring discourse representations of different computational complexity.
Larsson, T. (1988). Hardware Verification based on Algebraic Manipulation and Partial Evaluation. Technical Report LiTH-IDA-R-88-41, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc of IFIP WG 10.2 International Working Conference on "The Fusion of Hardware Design and Verification", Glasgow, Scotland, July 3-6, 1988. (bibtex),
Abstract: A verification method based on algebraic manipulation of behaviour and structure describing expressions is presented. As a framework for this method a set of canonization rules for boolean, arithmetic, relational and conditional expressions are proposed. A temporal function is associated with a set of demurral canonization rules and used to organize temporal reasoning. These rules are collected into a set of decision procedures that can be applied by a partial evaluator or by the user.
Larsson, T. and Peng, Z. (1988). A Relational Approach to VLSI Design Databases. Technical Report LiTH-IDA-R-88-37, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of the 36th ISMM International Conference on Mini and Microcomputers and Their Applications, Sant Feliu de Guixols, Spain, June 27-30, 1988. (bibtex),
Abstract: As the complexity of VLSI systems and their design tools increases, VLSI designers are now faced with the problem of managing a huge amount of data, which demands very efficient data management strategies and tools. One approach to deal with the problem is to build the VLSI design environment around a centralized database, i.e., to use a database to keep track of all different types of design data and maintain the logic relationship between them. This approach leads naturally to the integration of a CAD design environment. Some critical properties and requirements of such a database are discussed in this paper. An implementation model of a VLSI design database based on relational schemes is then described to meet the requirements.
Lennartsson, B. (1988). Multi-Level Software Architectures - Industrial Experiences and Research Directions. Technical Report LiTH-IDA-R-88-17, Department of Computer and Information Science, Linköping University, Sweden. This report is a revised version of a paper in Advance Working Papers of The Second International Workshop on Computer-Aided Software Engineering. Cambridge, Massachusetts. July 12-15, 1988. (bibtex),
Abstract: No abstract available
Leszczylowski, J., Bonnier, S., and Maluszynski, J. (1988). Logic Programming with External Procedures: Introducing S-Unification. Technical Report LiTH-IDA-R-88-01, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: A motivation for this work is the problem of re-usability of existing traditional software in logic programs. It can be viewed in an abstract way as the problem of amalgamation of Horn clause logic with a term reduction system whose rewrite rules are not accessible and thus cannot be used for construction of E-unifiers. Therefore we introduce a new unification algorithm, called S-unification, which is a special incomplete case of E-unification. It has the property that whenever it succeeds the result is a singleton complete set of E-unifiers of the arguments. It may also fail or report that it is not able to solve the problem of E-unification for given arguments. If the algorithm fails the actual arguments have no E-unifier. The paper discusses the problem of amalgamation of external functional procedures in a logic program and gives a characterization of a class of amalgamated programs for which S-unification is complete.
Nilsson, U. (1988). Inferring Restricted AND-Parallelism in Logic Programs Using Abstract Interpretation. Technical Report LiTH-IDA-R-88-02, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: No abstract available
Nilsson, U. (1988). Systematic Construction of Domains for Abstract Interpretation Frameworks. Technical Report LiTH-IDA-R-88-45, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: The paper addresses two issues --- initially sufficient conditions which ensure termination and correctness of abstract interpretations are formulated. Secondly we show how simple abstract domains which satisfy these conditions may be composed into more powerful and complex abstract domains which also satisfy the proposed requirements. We demonstrate the technique by constructing an abstract domain suitable for inferring (1) whether two variables are bound to terms with shared variables (2) whether a variable is bound to a ground term and (3) whether a variable is unbound or bound to another variable.
Nilsson, U. (1988). Toward a Framework for the Abstract Interpretation of Logic Programs. Technical Report LiTH-IDA-R-88-44, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: A new framework for abstract interpretation of logic programs is presented. The idea is to take as the basis a simplified semantics that approximates the standard operational semantics of logic programs but still makes it possible to derive non-trivial abstract interpretations. The relative simplicity of the basic semantics facilitates systematic derivation of abstract interpretations and static analyses of logic programs. Sufficient conditions for termination and correctness of the derived interpreters are provided. The approach is illustrated by inferring groundness information for an example program.
Padgham, L. (1988). NODE: A Database for Use by Intelligent Systems. Technical Report LiTH-IDA-R-88-26, Department of Computer and Information Science, Linköping University, Sweden. Accepted for publication in Proc. of ISMIS '88, Torino, Italy, October 12-15, 1988. (bibtex),
Abstract: We describe here a database, NODE (Network Object-Oriented Database Environment), which has been built as the base layer for LINCKS (Linköpings INtelligent Communication of Knowledge System), an ongoing research project in the Knowledge Representation Laboratory at Linköping University.The database was designed and built especially for the LINCKS project, which is a project aiming at a highly integrated intelligent system for use by end users in a wide variety of application areas. We give a brief overview of some of the goals in the larger project which motivated the design of the database. We also discuss some A.I. applications which are being built using NODE.
Padgham, L. and Rönnquist, R. (1988). From a Technical to a Humane Environment: A Software System Supporting Cooperative Work. Technical Report LiTH-IDA-R-88-19, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of the GDI International Conference on USER INTERFACES, Ruschlikon, Switzerland, October 20-21, 1986. (bibtex),
Abstract: This paper presents LINCKS, an environment which supports co-operative work. LINCKS is presently in the stage of beginning implementation at Linköping University.
Pagdham, L. (1988). A Model and Representation for Type Information and Its Use in Reasoning with Defaults. Technical Report LiTH-IDA-R-88-16, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of AAAI'88, American Association for Artificial Intelligence, 1988. (bibtex),
Abstract: Typing schemes which allow inheritance from super- to sub-types are a common way of representing information about the world. There are various systems and theories which use such representations plus some inferencing rules to deduce properties of objects, about which the system has only partial information. Many of these systems have problems related to multiple inheritance, and have some difficulty in drawing conclusions which we as humans see as intuitively simple.We present a model of typing based on a lattice of feature descriptors. A type is represented by two important points in the lattice representing core and default information. The use of two points allows some information to be monotonic whilst other information is nonmonotonic.We give some operations which can be used in default reasoning about an object, based on knowledge about the relationships between the points in the lattice which are defined as types. We then work through some specific examples, showing the conclusions which we reach with this system. We compare the expressiveness of our system to some of the well known work in the area of default reasoning using inheritance.
Pagdham, L. and Rönnquist, R. (1988). LINCKS: An Imperative Object Oriented System. Technical Report LiTH-IDA-R-88-15, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc of the 20th Annual Hawaii Int. Conf. on System Sciences, Hawaii, 1987. (bibtex),
Abstract: We present the LINCKS (Linköpings Intelligent Knowledge Communication System) system which is under development at Linköping University, and the theoretical model on which it is based. LINCKS is an object oriented system in the sense that objects in the real world are represented directly within the system, allowing for a clear and simple mapping from the real world to a computer model of some aspect of the real world. The object oriented model used differs significantly from that used in Smalltalk, Simula, and many other object oriented languages. The most fundamental differences are in the view of typing and the view of actions. A typing schema is regarded as part of the context for a user or a software tool, with many different typing schemas being allowed to co-exist within the system. Actions are not represented as messages and methods attached to objects as in Smalltalk. Instead actions have their own structure and organisation, and include information about their pre and post conditions. This gives the system a more imperative nature than many object oriented systems. A history mechanism is also described which allows recreation of any object as it existed at some previous point in time. The history mechanism also provides information to be used by reasoning software. LINCKS is compared to Smalltalk with respect to some important differences.
Patel, M. R. (1988). What should a Programming Environment for Threaded Interpretive Languages provide?. Technical Report LiTH-IDA-R-88-42, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of the 8th Rochester Forth Conference on Programming Environments, Rochester, New York, USA, June 1988. (bibtex),
Abstract: Given the low cost compiler and interpreter of Threaded Interpretive Languages, such as FORTH, an incremental and interactive programming style is more or less directly achieved. Traditionally program development may be regarded as a successive definition and testing of procedures and data structures. To reduce the complexity of the programming task and enhance reusage of code modules additional tools are required. This paper discusses some tools that should be available in a programming environment for Treaded Interpretive Languages. Some of the basic ideas from the advanced programming environments of INTERLISP and Smalltalk-80 are related and discussed.
Peng, Z. (1988). A Horizontal Optimization Algorithm for Data Path/Control Synthesis. Technical Report LiTH-IDA-R-88-35, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of the 1988 IEEE International Symposium on Circuits and Systems, Helsinki Univ. of Technology, Finland, June 7-9, 1988. (bibtex),
Abstract: This paper describes a new approach to register level synthesis of data path/control from high level behavioral descriptions. This approach utilizes a horizontal optimization algorithm which makes design decisions concerning operation scheduling, data path allocation and control allocation at the same time. The proposed algorithm works iteratively on parts of the design space selected according to their relationship to the current performance critical path. Experimental results show that the horizontal approach produces better results in respect to performance/cost than a vertical one that separates operation scheduling, data path allocation and control allocation into three subprocesses.
Peng, Z. (1988). Let's Design Asynchronous VLSI Systems. Technical Report LiTH-IDA-R-88-38, Department of Computer and Information Science, Linköping University, Sweden. Also published in Microprocessing and Microprogramming, the Euromicro Journal, Vol. 24, 1988. (bibtex),
Abstract: No abstract available
Peng, Z. (1988). Semantics of a Parallel Computation Model and its Applications in Digital Hardware Design. Technical Report LiTH-IDA-R-88-36, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of the 1988 International Conference on Parallel Processing, Pennsylvania State University, August 15-19, 1988. (bibtex),
Abstract: This paper describes a parallel computation model based on a data/control flow notation which consists of separate but related sub-models of data path and control. The data path is formulated as a directed graph. The control structure, on the other hand, is modelled as a Petri net. This model is used for specification and synthesis of digital hardware with a high degree of concurrency and parallelism. The semantics of the proposed model is defined in terms of its interactions with the environment. That is, two pieces of hardware are considered to be semantically equivalent if they interact with an environment in the same way. This allows manipulation of the internal structure of the hardware to improve performance as well as reduce cost. A set of transformations for the model which preserve its semantics is presented. A sequence of such transformations can be used to move a design from an abstract description to a final implementation.
Peng, Z., Kuchcinski, K., and Lyles, B. (1988). CAMAD: A Unified Data Path/Control Synthesis Environment. Technical Report LiTH-IDA-R-88-39, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of the IFIP TC-10 Conference on Design Methodologies for VLSI and Computer Architecture, Pisa, Italy, September 19-23, 1988. (bibtex),
Abstract: This paper describes a set of design tools built at Linköping University to support automated synthesis of integrated circuits. They consists of algorithms for 1) automatic generation of unified design representations from high level behavioral descriptions, 2) synthesis of optimal data path and control, and 3) partitioning of VLSI systems into asynchronous modules. The set of design tools is integrated to form a unified design environment based on a design representation model derived from timed Petri net notation. Several ongoing projects are being carried out to enrich the design environment and will also be discussed in this paper.
Rydqvist, G., Patel, M. R., and Larsson, L. (1988). Types in Space - Towards Flexible High-speed Object Oriented Data Management Tools of the Future. Technical Report LiTH-IDA-R-88-43, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: Algorithm selection and data modeling are key issues in programming activity. Concepts in the minds of human beings underlie these issues. Algorithm and data together, are models of the behavior of these concepts. Most traditional modeling support systems are based on the architecture of the executing hardware machines, and little attention has been given to the requirements of the underlying concepts.In this report we extract results from psychology as a starting point and consider the programming situation from that point of view. We use the resulting perspective to search for answers to a number of basic questions: What is the relation between concepts and their executable realizations? How do we achieve the necessary model power implied by this relation? Why are not traditional systems adequate?
Sandewall, E. (1988). An Approach to Non-Monotonic Entailment. Technical Report LiTH-IDA-R-88-32, Department of Computer and Information Science, Linköping University, Sweden. To appear in Methodologies for Intelligent Systems, vol. II, Proc. of ISMIS 1988 conference, Torino, Italy, 1988, Z.W. Ras and L. Saitta (eds), North Holland, 1988, pp. 391-397. (bibtex),
Abstract: No abstract available
Sandewall, E. (1988). Formal Semantics for Reasoning about Change with Ramified Causal Minimization. Technical Report LiTH-IDA-R-88-08, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: We deal with the frame problems, including the qualification problem, by requiring that for every state change there is a corresponding action causing it, and minimize the set of actions. An action may cause other actions occurring at the same time, or afterwards. The syntax and semantics are specified for a logic where this approach to the frame problem can be expressed stringently, and the proper minimization criterium is formulated.One characteristic feature of this work is that sub-structures which are used in the semantics, such as partial states and descriptors, are also "first class citizens" from the syntactic point of view. In this way we obtain a kind of reification, but with less formal overhead than when formulas are reified directly.
Sandewall, E. (1988). Future Developments in Artificial Intelligence. Technical Report LiTH-IDA-R-88-30, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. of European Conference on Artificial Intelligence (ECAI), Munich, August, 1988. (bibtex),
Abstract: This paper is the manuscript for the presentation of the invited paper at the European Conference on Artificial Intelligence (ECAI) in Munich in August, 1988. It is therefore more detailed than the extended abstract that is found in the conference proceedings.
Sandewall, E. (1988). Non-Monotonic Entailment for Reasoning about Time and Action. Part I: Sequential Actions. Technical Report LiTH-IDA-R-88-27, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: The paper defines a logic for reasoning about time and action, in terms of syntax, semantics, and preference relations on interpretations. Temporal logic with explicit representation of time-points is used, rather than situation calculus. The preference relations prefer (1) interpretations which maximize the expectations that fluents do not change, (2) interpretations which minimize the number of instances where fluents change in spite of expectations to the opposite, and (3) interpretations which minimize the set of actions. The preferential entailment relation based on these preferences is equally applicable to temporal projection, temporal explanation, and plan construction (as used for planning, story understanding, and diagnosis). A number of examples are described supporting the thesis that this semantics obtains the results dictated by common sense.
Sandewall, E. (1988). Non-Monotonic Entailment for Reasoning about Time and Action. Part II: Concurrent Actions. Technical Report LiTH-IDA-R-88-28, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: An explicit temporal logic for reasoning about time and action is extended in order to account for concurrency between actions. The extensions are such that in no model can several actions co-occur if they control the same property (i.e. influence it so that it changes or may change). Also, several actions which require the same property to be held at the same value are allowed to co-occur, but they can not in turn co-occur with even one action that controls that property. In this way, traditional concepts in the study of concurrent processes have been imported into the formal-logical framework.
Sandewall, E. (1988). Non-Monotonic Entailment for Reasoning about Time and Action. Part III: Decision Procedure. Technical Report LiTH-IDA-R-88-29, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: No abstract available
Sandewall, E. (1988). The Semantics of Non-Monotonic Entailment Defined Using Partial Interpretations. Technical Report LiTH-IDA-R-88-31, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: No abstract available
Sandewall, E. et al. (1988). Department of Computer and Information Science Annual Research Report 1987. Technical Report LiTH-IDA-R-88-07, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: No abstract.
Sandewall, E., Hultman, J., and Tengvald, E. (1988). Software Architecture and Programming Paradigms for Robotics Applications. Technical Report LiTH-IDA-R-88-12, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: We propose a layered software architecture intended for robotics applications, where there is a data flow from sensors to actuators.
Tengvald, E. (1988). Ett kartorienterat planeringssystem för autonoma farkoster, en design diskussion. Technical Report LiTH-IDA-R-88-13, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: Sammanfattning Efter några inledande definitioner och en kort beskrivning av den så kallade "run length" representationen följer en noggrann genomgång av ett konkret kartorienterat planeringsproblem, finna väg problemet: Att finna den kortaste hinderfria färdvägen mellan givna start och målpositioner. Därefter beskrivs en effektiv finna vägproblemlösare arbetande med spatiella högnivåbegrepp. Mer komplexa finna vägproblem i vilka hänsyn tas till, exempelvis, strömförhållanden och risk för upptäckt diskuteras därefter. I detta sammanhang beskrivs en tämligen beräkningskrävande pixelorienterad finna vägproblemlösare, vilken kan hantera dessa mer komplexa problem.Med utgångspunkt från finna vägproblemet och dess lösning beskrivs så en översiktlig design för ett kartorienterat planeringssystem. Efter en noggrannare beskrivning av "run length" representationen diskuteras ett system av pixel,tripel och rektangelregler vilka gör det möjligt att höja nivån på programmeringen av planeringsystemets lägre nivåer. Därefter följer en genomgång av grundläggande mellannivåoperatorer såsom, mängdoperatorer, komposition av funktioner med mera. Efter detta beskrivs ett högnivåmaskineri baserat i de ovan nämnda spatiella högnivåbegreppen. Den översiktliga designen avslutas med en beskrivning av hur kommunikationen mellan de låga och höga nivåerna kan utföras.Efter detta diskuteras principer för design av kunskapsrepresentationssystem i allmännhet och kartorienterade planeringssystem i synnerhet. Ytterligare kartorienterade planeringsproblem, närmast: Besöka platser, att givet ett antal platser finna den kortaste vägen som besöker alla platser, Avsöka yta, att finna den kortaste väg vilken täcker samtliga punkter på en yta, beskrivs översiktligt. Slutligen diskuteras och utvärderas två alternativ till "run length" representationen nämligen quad-träd och splines.
Wire'n, M. (1988). A Control-Strategy-Independent Parser for PATR. Technical Report LiTH-IDA-R-88-10, Department of Computer and Information Science, Linköping University, Sweden. Also in Proc. First Scandinavian Conference on Artificial Intelligence, Tromsö, Norway, March 9/11, 1988. (bibtex),
Abstract: No abstract available
Wire'n, M. (1988). An Incremental Chart Parser for PATR. Technical Report LiTH-IDA-R-88-11, Department of Computer and Information Science, Linköping University, Sweden. (bibtex),
Abstract: No abstract available