Formalizing planning knowledge for hierarchical planning

A hierarchical planning system achieves efficiency by planning with the most important conditions first, and considering details later in the planning process. Few attempts have been made to formalize the structure of the planning knowledge for hierarchical planning. For a given domain, there is usually more than one way to define its planning knowledge. Some of the definitions can lead to efficient planning, while others may not. In this paper, we provide a set of restrictions which defines the relationships between a non-primitive action and its set of subactions. When satisfied, these restrictions guarantee improved efficiency for hierarchical planning. One important feature of these restrictions is that they are syntactic and therefore do not depend on the particular structure of any plan. Along with these restrictions, we also provide algorithms for preprocessing the planning knowledge of a hierarchical planner. When used during planning, the preprocessed operator hierarchies can enable a planner to significantly reduce its search space.     

Representing moving objects in computer-based expert systems: the overtake event example

Qualitative formalisms suited to express qualitative temporal or spatial relationships between entities, have gained wide acceptance as a useful way of abstracting from the real world. The question remains how to describe spatio-temporal concepts, such as the interaction between moving objects, adequately within a qualitative calculus and more specifically how to use this in expert systems. With this in mind, the Qualitative Trajectory Calculus (QTC) has been introduced. QTC enables comparisons between positions of objects at different time points to be made. By reducing the continuum to the qualitative values −, 0 and +, continuous movements can be described qualitatively. To illustrate the naturalness of QTC, the overtake event is studied. An overtake event is a typical example of objects moving in a particular domain and can become important, for example in the study of traffic engineering. A so-called conceptual animation is represented, being a sequence of QTC-relations, following the constraints imposed by qualitative reasoning. It is shown that different kinds of behaviour having certain common characteristics are reflected by the structure (e.g. symmetrical aspects) of the conceptual animations.     

An historical overview of natural language processing systems that learn

A fundamental issue in natural language processing is the prerequisite of an enormous quantity of preprogrammed knowledge concerning both the language and the domain under examination. Manual acquisition of this knowledge is tedious and error prone. Development of an automated acquisition process would prove invaluable.This paper references and overviews a range of the systems that have been developed in the domain of machine learning and natural language processing. Each system is categorised into either a symbolic or connectionist paradigm, and has its own characteristics and limitations described.     

定量问题求解专家系统——ESQPS

定量问题求解系统,是人工智能和专家系统研究领域的一个重要课题。本文介绍了ＥＳＱＰＳ－一个应用面向对象（ＯＯ）技术开发,可用于科学和工程技术领域中求解基本物理问题的专家系统,简述了该系统的知识表达和问题求解方法的设计思想和实现技术。     

Management of system development knowledge: a cognitive approach

The management of system development knowledge (SDK) is currently sub-optimal regarding the system developer's learning and use of the knowledge due to its inherently complex and cumbersome nature. In this work, we have identified and categorised different approaches to the management of SDK generally having instrumental and technical subject matter. To complement the current literature in this field of study, our approach to the management of SDK has taken into account the system developer's cognitive processing concerns. As such, we have proposed and successfully tested a strategic method for SDK management in a real working situation. In this empirical study, the implementation of an artificial knowledge structure has been shown to be useful as a means of decreasing the system developer's cognitive processing load as regards SDK. The first of two implications is such that cognitive consideration in relation to SDK management has further developmental potential. The second implication is that the system development environment can provide cognitive support to the system developer.     

LIM-G: Learner-initiating instruction model based on cognitive knowledge for geometry word problem comprehension

Computer-assisted instruction systems have been broadly applied to help students solve math word problem. The majority of such systems, which are based on an instructor-initiating instruction strategy, provide pre-designed problems for the learners. When learners are asked to solve a word problem, the system will instruct the learners what to do. However, systems employing an instructor-initiating instruction strategy offer little help to advanced learners or to learners encountering problems that are not in the pre-designed database. Therefore, in this study, a learner-initiating instruction model (LIM-G) is proposed to help learners’ comprehension of geometry word problems. Geometry word problems are math word problems involving geometric concepts. Many researches indicate that learners encounter difficulties while comprehending math word problems. In this model, a learner can seek help with any geometry word problem he is interested in. Based on a learner-initiating instruction strategy, LIM-G first comprehends the problem and then gives the learner the telegraphic and diagrammatic representations of the problem, which are more intuitive to understand. For LIM-G, the comprehension mechanism plays a critical role in solving word problems. For this study, a system is built based on LIM-G. In this system, the cognitive knowledge needed for comprehending geometry word problem is constructed with an ontology-based tool called InfoMap. Using cognitive knowledge and frame-template structures, the system can extract the relevant concepts in geometry word problems for comprehension.     

Why cognitive science is not formalized folk psychology

It is often assumed that cognitive science is built upon folk psychology, and that challenges to folk psychology are therefore challenges to cognitive science itself. We argue that, in practice, cognitive science and folk psychology treat entirely non-overlapping domains: cognitive science considers aspects of mental life which do not depend on general knowledge, whereas folk psychology considers aspects of mental life which do depend on general knowledge. We back up our argument on theoretical grounds, and also illustrate the separation between cognitive scientific and folk psychological phenomena in a number of cognitive domains. We consider the methodological and theoretical significance of our arguments for cognitive science research.     

User modelling for adaptive computer systems: a survey of recent developments

User modelling is becoming an important sub-area of Artificial Intelligence with both theoretical and practical consequences. The theoretical foundations of user modelling are to be found in key areas of AI, such as knowledge representation and plan recognition, while its practical applications impinge on the construction of intelligent user interfaces and adaptive systems. This paper provides a survey of current work in user modelling. The paper begins by distinguishing between AI approaches, which are the subject of this survey, and those of HCI (Human-Computer Interaction) and then considers the major issues in user modelling such as: types of user modelling system, the sorts of information modelled, how the information is acquired, represented and used. The paper concludes by examining some of the more problematic aspects of user modelling as well as indicating areas for future research.     

PSE: An Object-Oriented Representation for Modeling and Managing Part-of Relationships

Part-of relationships are needed to model structures of composite objects. Especially, composite objects, known as physical assemblies, are very popular in several applications. The existing object-oriented representations of physical assemblies and query languages based on them have several disadvantages. For example, they suppose that the user knows the structure of a physical assembly completely. This is not a realistic requirement in those cases where a physical assembly consists of a huge number of parts. Likewise the user has in them to control traversals of physical assemblies, i.e. they have a low degree of declarativity. Further, they do not support intensional and combined extensional-intensional queries which would be necessary in an advanced manipulation of physical assemblies. We develop the PSE (Part-of Structure Element) representation for removing the above disadvantages. The PSE representation is a set theoretical and constructor-oriented representation for physical assemblies and it can be used in the implementation based on both the object-oriented and deductive object-oriented database (DOOD) paradigms.     

Control and Cross-Domain Mental Computation: Evidence from Language Breakdown

This paper uses the notion of control from programming languages to look at the organization of mental code. Data for the analysis comes principally from language breakdown. The paper first outlines the well known distinction between logic and control in algorithms and argues that the same distinction holds in mental code. Discussion then focuses mainly on control—the management of data flow—and shows that a variety of language disorders affect either the logic component of the mental algorithms for language (e.g., Specific Language Impairment) or the control component (e.g., Williams syndrome and Turner syndrome). A comparative study of the loss of morphology in Williams syndrome and Specific Language Impairment reinforces the logic/control split as an accurate guide to the explanation of linguistic behavior in these disorders. The data, moreover, are not accountable to sheer performance factors, but to the way the disorders disrupt the structure of mental algorithms. The paper closes with a discussion of how control and the management of cross-domain computation fit into recent theories of modular mental architecture and proposals about the explicitness of representations and their availability to working memory.     

Two Projects for Understanding the Mind: A Response to Morris and Richardson

We respond to Morris and Richardson's (1995) claim that Pickering and Chater's (1995) arguments about the lack of a relation between cognitive science and folk psychology are flawed. We note that possible controversies about the appropriate uses for the two terms do not affect our arguments. We then address their claim that computational explanation of knowledge-rich processes has proved possible in the domains of problem solving, scientific discovery, and reasoning. We argue that, in all cases, computational explanation is only possible for aspects of those processes that do not make reference to general knowledge. We conclude that consideration of the issues raised by Morris and Richardson reinforces our original claim that there are two fundamentally distinct projects for understanding the mind, one based on justification, and the other on computational explanation, and that these apply to non-overlapping aspects of mental life.     

Intelligent Database Design Diagnosis: Performance Assessment with the Provision of Domain Knowledge

Techniques for representing and exploitingdomain knowledge (such as the dictionary,thesaurus and knowledge reconciliationtechniques) have long been used by intelligentdatabase design tools when performing the taskof design synthesis. However, the capacity ofthese techniques to enhance the diagnosticcapabilities of intelligent database designtools has yet to be explored and evaluated.This paper presents such an evaluation,focusing upon the aforementioned techniques ofdictionary, thesaurus and knowledgereconciliation. Results obtained from thisinvestigation suggest that use of thesetechniques has the potential to increase thediagnostic capabilities of intelligent databasedesign tools by facilitating detection andresolution of design inconsistencies that wouldremain undiscovered in situations where suchsystem-held domain knowledge was not available.     

Information Compression by Multiple Alignment, Unification and Search as a Unifying Principle in Computing and Cognition

This article presents an overview ofthe idea that information compression bymultiple alignment, unification and search(ICMAUS) may serve as a unifying principle incomputing (including mathematics and logic) andin such aspects of human cognition as theanalysis and production of natural language,fuzzy pattern recognition and best-matchinformation retrieval, concept hierarchies withinheritance of attributes, probabilisticreasoning, and unsupervised inductive learning.The ICMAUS concepts are described together withan outline of the SP61 software model in whichthe ICMAUS concepts are currently realised. Arange of examples is presented, illustratedwith output from the SP61 model.     

User diversity and design representation: Towards increased effectiveness in Design for All

This paper addresses user modelling for “Design for All” in a model-based approach to Human-Computer Interaction, paying particular attention to placing user models within organisational role- and task-related contexts. After reviewing a variety of user modelling approaches, and deriving requirements for user modelling related to Design for All, the paper proposes a role-driven individualised approach. Such an approach is based on a model-based representation schema and a unifying notation that keeps the user’s models and the contextual information transparent and consistent. Individualisation is achieved by coupling symbolic model specifications with neural networking on synchronisation links between symbolic representation elements. As a result, user modelling for Design for All is achieved not by stereotypical user properties and functional roles, but by accommodating the actual users’ behaviour. Published online: 18 May 2001