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By the end of the century, NASA will launch a series of satellites to study the Earth. NASA will store the Earth data in one of the world's largest information systems, whose size will be 1,000 times larger than the Library of Congress. Based upon a current infrastructure of Earth science validation centers throughout the world, this paper describes a highly distributed architecture for the management,...
In this paper I survey over a decade of work on how we understand how things work. Much of this work has been conducted in the context of reasoning about functions of devices. I briefly overview a representational framework called Functional Representation, and indicate how a device representation in this language can be used for simulation, diagnosis and design. I make remarks about the generality...
Building digital libraries is one of the most important Grand Challenge problems faced by information professionals. This paper surveys the relevant literature and includes recommendations for research, based on our experience with a digital library for computer science and its use in improving undergraduate education. Of particular interest is the application of intelligent system methods to help...
As the primary targets for exercises of re-engineering and interoperability, so-called prosaic application domains and their associated systems provide interesting and practically useful case studies for a treatment of semantics from a methodological as well as cognitive point of view. (In this paper we treat cognition as the process of linking knowledge to perception inside an intelligent agent.)...
While the problem of incomplete data in databases has been extensively studied, a relatively unexplored form of uncertainty in databases, called inaccurate data, demands due attention. Inaccurate data results when data are contributed by various information agents with associated credibility. Though the data itself is total or complete, the reliability of the data now depends on the agents' credibility...
Pavelka [10] had shown in 1979 that the only natural way of formalizing fuzzy logic for truth-value in the unit interval [0,1] is by using Lukasiewicz's implication operator a→b = min{1, 1−a+b} or some isomorphic form of it A considerable number of other papers around the same time had attempted to formulate alternative definitions for a→b by giving intuitive justifications for them. There continues...
Mathematicians formalized the approximation in terms of topology. In this paper a new family of logic systems for approximate reasoning, called Near Logic, is proposed; their semantics are rested on the notion of neighborhood system-a building block of topology. Somewhat surprisingly, the axiom schema of the Near Logic is that of the modal logic S4. This generalizes the fact that the axiom schema...
The language of signed formulas offers a classical logic frame-work for multiple-valued logics. Fuzzy operator logic is cast in this frame-work, thereby making most classical inference techniques applicable to fuzzy logic. In particular, resolution for first order fuzzy operator logic is shown to be a special case of signed resolution.
We show how to organize a collection of intelligent cooperating agents into a rough mereological controller for the purpose of assembling a complex object with desired quality from its elementary parts. This scheme for synthesis of a complex object from its elementary parts provides a framework for e.g. quality control in concurrent engineering as well as cooperative problem-solving.
In probabilistic reasoning when we have to build a probability distribution on some events and no further information is available, we then apply the insufficient reasoning principle; i.e. we assume that the events have equal opportunities to occur. In our previous work we have observed that in the Dempster-Shafer theory of evidence the principle is not applied when using Dempster's rule of combination...
This paper suggests a a global measure of ambiguity based on the notion of an interval structure which can be viewed as a qualitative measure of belief. It is shown that the boundary region in the roughset model is a special case of the proposed measure. To demonstrate the usefulness of this new measure, it is being used as a criterion for selecting appropriate attributes in the construction of decision...
This paper describes a novel methodology for meta-level control of approximate reasoning. We show that approximate reasoning performed by anytime algorithms offers a simple means by which an intelligent system can trade-off decision quality for deliberation cost. The model exploits probabilistic knowledge about the environment and about the performance of each component in order to optimally manage...
In this paper three formal models of selection operators (two known from the literature and one newly porposed) for genetic algorithms, used to learn structured concepts descriptions containing small disjuncts, are presented. The evolution of a population, according to these operators, with a generation gap equal to or less than one, is investigated in order to assess their ability to let different...
In this paper the utility of several constraint-handling techniques is investigated on the basis of a family of 0/1 knapsack problems. Several evolutionary algorithms are applied to this NP-hard problem. The conclusions might be applicable to many constrained combinatorial optimization problems, for which the use of evolutionary algorithm is considered.
In this paper, we present a cooperative approach intended to avoid empty answers to conjunctive fuzzy relational queries. We propose a weakening mechanism generating more tolerant queries. This consists in relaxing one or several fuzzy predicates with the help of a fuzzy linguistic modifier which is used to build a lattice of weakened queries expressing a semantic distance between these queries. Selectivity...
This paper describes a technique to support interoperable query processing when multiple heterogeneous knowledge servers are accessed. The problem is to support query transformation transparently, so a user can pose queries locally, without the need of global knowledge about different data models and schema. In this paper, we focus on transforming SQL source queries, posed against a relational schema,...
An attribute-oriented induction has been developed in the previous study of knowledge discovery in databases. A concept tree ascension technique is applied in concept generalization. In this paper, we extend the background knowledge representation from an unconditional non-rule-based concept hierarchy to a rule-based concept hierarchy, which enhances greatly its representation power. An efficient...
This paper describes knowledge acquisition methods and a force generation decision aid, ForMAT, that has been developed to support the acquisition, representation, and dissemination of knowledge about military forces for use in solving large scale planning problems. The paper describes the problem domain, how the knowledge acquisition was performed in general and with the use of ForMAT through a coupling...
Traditional DBMS only retrieves data that perfectly match the user query and also requires the user to know the detailed database schema. Often, it is desirable to obtain additional relevant information to a query. In this paper, we present a method to provide useful information to the user that he does not explicitly asked for. Such domain specific knowledge associated to a given query depends on...
This paper presents a new method for the computation of bound linear Datalog queries and compares its performance to that of other bottom-up execution strategies. The technique, called pushdown method, uses virtual stacks to store information on the current state of the evaluation thus ensuring both termination and efficient execution. The asymptotic worst-case behavior and experimental results for the new method compare favorably against those of previous methods...
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