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1.
After having recalled some well-known shortcomings linked with the Semantic Web approach to the creation of (application oriented) systems of “rules” – e.g., limited expressiveness, adoption of an Open World Assumption (OWA) paradigm, absence of variables in the original definition of OWL – this paper examines the technical solutions successfully used for implementing advanced reasoning systems according to the NKRL’s methodology. NKRL (Narrative Knowledge Representation Language) is a conceptual meta-model and a Computer Science environment expressly created to deal, in an ‘intelligent’ and complete way, with complex and content-rich non-fictional ‘narrative’ data sources. These last include corporate memory documents, news stories, normative and legal texts, medical records, surveillance videos, actuality photos for newspapers and magazines, etc. In this context, we will expound first the need for distinguishing between “plain/static” and “structured/dynamic” knowledge and for introducing appropriate (and different) knowledge representation structures for these two types of knowledge. In a structured/dynamic context, we will then show how the introduction of “functional roles” – associated with the possibility of making use of n-ary structures – allows us to build up highly ‘expressive’ rules whose “atoms” can directly represent complex situations, actions, etc. without being restricted to the use of binary clauses. In an NKRL context, “functional roles” are primitive symbols interpreted as “relations” – like “subject”, “object”, “source”, “beneficiary”, etc. – that link a semantic predicate with its arguments within an n-ary conceptual formula. Functional roles contrast then with the “semantic roles” that are equated to ordinary concepts like “student”, to be inserted into the “non-sortal” (no direct instances) branch of a traditional ontology.  相似文献   

2.
Gian Piero Zarri 《Knowledge》2011,24(7):989-1003
This paper describes an experimental work carried out in the framework of an important European project to create and make use of a wide-ranging knowledge base in the gas/oil domain. In the context of this work, “knowledge base” means a collection of formal statement relating, with a negligible loss of information, the inner content (the ‘meaning’) of “complex events” included in two different “storyboards”. These events – originally presented under the form of unstructured natural language information – concern some general activities proper to the management of gas/oil facilities, like recognizing and monitoring gas leakage alarms in a gas processing plant or triggering the different steps needed to activate a gas turbine. To express this sort of information and to set up the knowledge base, the NKRL (Narrative Knowledge Representation Language) formalism has been used. NKRL is a conceptual meta-model and Computer Science environment expressly created to deal, in an ‘intelligent’ and complete way, with complex and content-rich ‘narrative’ data sources. The final knowledge base has been firstly tested in depth using the standard NKRL querying and information retrieval tools. High-level inference procedures have then been used, both “transformation rules” – unsuccessful queries are ‘transformed’ to produce results that are ‘semantically similar’ to those searched for initially – and “hypothesis rules” – information in the knowledge base is automatically aggregated to supply a sort of ‘causal’ explanation of some retrieved events.  相似文献   

3.
Tenenberg, Roth and Socha (2016) documents interaction within a paired programming task. The analysis rests on a conceptualization the authors term “We-awareness.” “We-awareness”, in turn, builds on Tomasello’s notion of “shared intentionality” and through it, upon Clark’s formulation of Common Ground (CG). In this commentary I review the features of CG. I attempt to show that neither Tomasello’s (2014) notion of “shared intentionality” nor Clark’s (1996) model of CG-shared develop an adequate treatment of the sequential emergence of subjective meaning. This is a critical problem for CG and other conceptualizations that build upon it (e.g., “shared intentionality”, “We-awareness”). And it calls into question their usefulness for building an analytic apparatus for studying mutual awareness at the worksite. I suggest that Schütz’s (1953) model of “motive coordination” might serve as a better starting place.  相似文献   

4.
An application of Narrative Knowledge Representation Language (NKRL) techniques on (declassified) ‘terrorism in Southern Philippines’ documents has been carried out in the context of the IST Parmenides project. This paper describes some aspects of this work: it is our belief, in fact, that the Knowledge Representation techniques and the Intelligent Information Retrieval tools used in this experiment can be of some interest also in an ‘Ontological Modelling of Legal Events and Legal Reasoning’ context.  相似文献   

5.
A Prolog-based natural language front-end system is described with the following major issues of discussion: Domain independence of the syntax analyser was achieved by the ‘generate-and-test’ notion and the domain independent semantic representation; Determiners were treated as higher order predicates; A technique called ‘syntactic feature’ was employed to write a readable parser in Prolog.  相似文献   

6.
GEHEIMSCHREIBER     
WOLFGANG MACHE 《Cryptologia》2013,37(4):230-242
World War II's “Fish” cipher was a British cover word for all kinds of encrypted German radio teleprinter messages. The GC&CS at Bletchley, Buckinghamshire, did not only attack successfully Enigma traffic (Morse signals on radio links) by the electromechanical deciphering machines called BOMBES. In addition, Bletchley's electronic text processor COLOSSUS broke the German “Tunny” ciphers, generated by TELEPRINTER ATTACHMENTS “SZ”, employed by the ‘Heer’ (Army) on HF radio links.  相似文献   

7.
We present a logic programming language, GCLA*** (Generalized horn Clause LAnguage), that is based on a generalization of Prolog. This generalization is unusual in that it takes a quite different view of the meaning of a logic program—a “definitional” view rather than the traditional logical view. GCLA has a number of noteworthy properties, for instance hypothetical and non-monotonic reasoning. This makes implementation of reasoning in knowledge-based systems more direct in GCLA than in Prolog. GCLA is also general enough to incorporate functional programming as a special case. GCLA and its syntax and semantics are described. The use of various language constructs are illustrated with several examples.  相似文献   

8.
Fuzzy prolog     
Various methods of representing uncertainty are discussed including some fuzzy methods. Representation and calculation of fuzzy expressions are discussed and a symbolic representation of fuzzy quantities coupled with axiomatic evaluation is proposed. This is incorporated into the PROLOG language to produce a fuzzy version. Apart from enabling imprecise facts and rules to be expressed, a natural method of controlling the search is introduced, making the search tree admissible.Formal expression of heuristic information in the same language, FUZZY PROLOG, as the main problem language follows naturally and therefore allows the same executor to evaluate in both “problem” space and “heuristic” space.In addition, the use of variable functors in the specification of bidirectional logic is discussed. The paper shows two areas of application of higher order fuzzy predicates. As an introduction Warren's examples are outlined and used with variable functors to illustrate their use in describing some relatively conventional applications.Translation of English into horn clause format is described and is used to illustrate the simplicity of representation using variable functors. Alternative formulations are also explored, typically the use of the “meta-variable” in MICRO-PROLOG and using the “univ” operator.Representation of rule generation and inference is addressed. Examples are given where the expression of meta-rules in standard PROLOG are compared with the expression of the same rules using “variable” predicate symbols. Some meta-rules illustrated are clearly not universally valid and this leads to the addition of fuzzy tokens.  相似文献   

9.
Clark’s query evaluation procedure for computing negative information in deductive databases using a “negation as failure” inference rule requires a safe computation rule which may only select negative literals if they are ground. This is a very restrictive condition, which weakens the usefulness of negation as failure in a query evaluation procedure. This paper studies the definition and properties of the “not” predicate defined in most Prolog systems which do not enforce the above mentioned condition of a safe computation rule. We show that the negation in clauses and the “not” Predicate of Prolog are not the same. In fact a Prolog program may not be in clause form. An extended query evaluation procedure with an extended safe computation rule is proposed to evaluate queries which involve the “not” predicate. The soundness and completeness of this extended query evaluation procedure with respect to a class of logic programs are proved. The implementation of such an extended query evaluation procedure in a Prolog system can be implemented by a preprocessor for executing range restricted programs and requires no modification to the interpreter/compiler of an existing Prolog system. We compare this proposed extended query evaluation procedure with the extended program proposed by Lloyd and Topor, and the negation constructs in NU-Prolog. The use of the “not” predicate for integrity constraint checking in deductive databases is also presented.  相似文献   

10.
Kurt Gödel’s Incompleteness theorem is well known in Mathematics/Logic/Philosophy circles. Gödel was able to find a way for any given P (UTM), (read as, “P of UTMforProgram of Universal Truth Machine”), actually to write down a complicated polynomial that has a solution iff (=if and only if), G is true, where G stands for a Gödel-sentence. So, if G’s truth is a necessary condition for the truth of a given polynomial, then P (UTM) has to answer first that G is true in order to secure the truth of the said polynomial. But, interestingly, P (UTM) could never answer that G was true. This necessarily implies that there is at least one truth a P (UTM), however large it may be, cannot speak out. Daya Krishna and Karl Potter’s controversy regarding the construal of India’s Philosophies dates back to the time of Potter’s publication of “Presuppositions of India’s Philosophies” (1963, Englewood Cliffs Prentice-Hall Inc.) In attacking many of India’s philosophies, Daya Krishna appears to have unwittingly touched a crucial point: how can there be the knowledge of a ‘non-cognitive’ mok?a? [‘mok?a’ is the final state of existence of an individual away from Social Contract]—See this author’s Indian Social Contract and its Dissolution (2008) mok?a does not permit the knowledge of one’s own self in the ordinary way with threefold distinction, i.e., subject–knowledge-object or knower–knowledge–known. But what is important is to demonstrate whether such ‘knowledge’ of non-cognitive mok?a state can be logically shown, in a language, to be possible to attain, and that there is no contradiction involved in such demonstration, because, no one can possibly express the ‘experience-itself’ in language. Hence, if such ‘knowledge’ can be shown to be logically not impossible in language, then, not only Daya Krishna’s arguments against ‘non-cognitive mok?a’ get refuted but also it would show the possibility of achieving ‘completeness’ in its truest sense, as opposed to Gödel’s ‘Incompleteness’. In such circumstances, man would himself become a Universal Truth Machine. This is because the final state of mok?a is construed as the state of complete knowledge in Advaita. This possibility of ‘completeness’ is set in this paper in the backdrop of ?rī ?a?karācārya’s Advaitic (Non-dualistic) claim involved in the mahāvākyas (extra-ordinary propositions). (Mahāvākyas that ?a?kara refers to are basically taken from different Upani?ads. For example, “Aham Brahmāsmi” is from B?hadāra?yaka Upanisad, and “Tattvamasi” is from Chāndogya Upani?ad. ?rī ?a?karācārya has written extensively. His main works include his Commentary on Brahma-Sūtras, on major Upani?ads, and on ?rīmadBhagavadGītā, called Bhā?yas of them, respectively. Almost all these works are available in English translation published by Advaita Ashrama, 5 Dehi Entally Road, Calcutta, 700014.) On the other hand, the ‘Incompleteness’ of Gödel is due to the intervening G-sentence, which has an adverse self-referential element. Gödel’s incompleteness theorem in its mathematical form with an elaborate introduction by R.W. Braithwaite can be found in Meltzer (Kurt Gödel: on formally undecidable propositions of principia mathematica and related systems. Oliver &; Boyd, Edinburgh, 1962). The present author believes first that semantic content cannot be substituted by any amount of arithmoquining, (Arithmoquining or arithmatization means, as Braithwaite says,—“Gödel’s novel metamathematical method is that of attaching numbers to the signs, to the series of signs (formulae) and to the series of series of signs (“proof-schemata”) which occur in his formal system…Gödel invented what might be called co-ordinate metamathematics…”) Meltzer (1962 p. 7). In Antone (2006) it is said “The problem is that he (Gödel) tries to replace an abstract version of the number (which can exist) with the concept of a real number version of that abstract notion. We can state the abstraction of what the number needs to be, [the arithmoquining of a number cannot be a proof-pair and an arithmoquine] but that is a concept that cannot be turned into a specific number, because by definition no such number can exist.”.), especially so where first-hand personal experience is called for. Therefore, what ultimately rules is the semanticity as in a first-hand experience. Similar points are voiced, albeit implicitly, in Antone (Who understands Gödel’s incompleteness theorem, 2006). (“…it is so important to understand that Gödel’s theorem only is true with respect to formal systems—which is the exact opposite of the analogous UTM (Antone (2006) webpage 2. And galatomic says in the same discussion chain that “saying” that it ((is)) only true for formal systems is more significant… We only know the world through “formal” categories of understanding… If the world as it is in itself has no incompleteness problem, which I am sure is true, it does not mean much, because that is not the world of time and space that we experience. So it is more significant that formal systems are incomplete than the inexperiencable ‘World in Itself’ has no such problem.—galatomic”) Antone (2006) webpage 2. Nevertheless galatomic certainly, but unwittingly succeeds in highlighting the possibility of experiencing the ‘completeness’ Second, even if any formal system including the system of Advaita of ?a?kara is to be subsumed or interpreted under Gödel’s theorem, or Tarski’s semantic unprovability theses, the ultimate appeal would lie to the point of human involvement in realizing completeness since any formal system is ‘Incomplete’ always by its very nature as ‘objectual’, and fails to comprehend the ‘subject’ within its fold.  相似文献   

11.
We examine Gärdenfors’ theory of conceptual spaces, a geometrical form of knowledge representation (Conceptual spaces: The geometry of thought, MIT Press, Cambridge, 2000), in the context of the general Creative Systems Framework introduced by Wiggins (J Knowl Based Syst 19(7):449–458, 2006a; New Generation Comput 24(3):209–222, 2006b). Gärdenfors’ theory offers a way of bridging the traditional divide between symbolic and sub-symbolic representations, as well as the gap between representational formalism and meaning as perceived by human minds. We discuss how both these qualities may be advantageous from the point of view of artificial creative systems. We take music as our example domain, and discuss how a range of musical qualities may be instantiated as conceptual spaces, and present a detailed conceptual space formalisation of musical metre.  相似文献   

12.
13.
An emerging model in concurrent product design and manufacturing is the federation of workgroups across traditional functional ‘silos’. Along with the benefits of this concurrency comes the complexity of sharing and accessing design information. The primary challenge in sharing design information across functional workgroups lies in reducing the complex expressions of associations between design elements. Collaborative design systems have addressed this problem from the perspective of formalizing a shared ontology or product model. We share the perspective that the design model and ontology are an expression of the ‘meaning’ of the design and provide a means by which information sharing in design may be achieved. However, in many design cases, formalizing an ontology before the design begins, establishing the knowledge sharing agreements or mapping out the design hierarchy is potentially more expensive than the design itself. This paper introduces a technique for inducing a representation of the design based upon the syntactic patterns contained in the corpus of design documents. The association between the design and the representation for the design is captured by basing the representation on terminological patterns at the design text. In the first stage, we create a ‘dictionary’ of noun-phrases found in the text corpus based upon a measurement of the content carrying power of the phrase. In the second stage, we cluster the words to discover inter-term dependencies and build a Bayesian belief network which describes a conceptual hierarchy specific to the domain of the design. We integrate the design document learning system with an agent-based collaborative design system for fetching design information based on our ‘smart drawings’ paradigm.  相似文献   

14.
A. Drexl 《Computing》1988,40(1):1-8
The multiconstraint 0–1 knapsack problem encounters when deciding how to use a knapsack with multiple resource constraints. The problem is known to be NP-hard, thus a “good” algorithm for its optimal solution is very unlikely to exist. We show how the concept of simulated annealing may be used for solving this problem approximately. 57 data sets from literature demonstrate, that the algorithm converges very rapidly towards the optimum solution.  相似文献   

15.
Distance automata are automata weighted over the semiring \((\mathbb {N}\cup \{\infty \},\min , +)\) (the tropical semiring). Such automata compute functions from words to \(\mathbb {N}\cup \{\infty \}\). It is known from Krob that the problems of deciding ‘ fg’ or ‘ f=g’ for f and g computed by distance automata is an undecidable problem. The main contribution of this paper is to show that an approximation of this problem is decidable. We present an algorithm which, given ε>0 and two functions f,g computed by distance automata, answers “yes” if f≤(1?ε)g, “no” if f≦?g, and may answer “yes” or “no” in all other cases. The core argument behind this quasi-decision procedure is an algorithm which is able to provide an approximated finite presentation of the closure under products of sets of matrices over the tropical semiring. Lastly, our theorem of affine domination gives better bounds on the precision of known decision procedures for cost automata, when restricted to distance automata.  相似文献   

16.
17.
Unlike most other logic programming languages. Concurrent Prolog5) does not include a sequential-AND operator to enforce serial goal (process) reduction. However, sequential process reduction is still possible using existing constructs. In a number of published programming examples it is achieved with the “commit” operator. Such programs may not execute as described, but instead encounter deadlock. In this paper several examples of this are presented, the cause of the problem is diagnosed, and a solution suggested. This paper also deals with sequential process reduction in more general terms. The methods available to achieve serialization involving commit and read-only variable references are analyzed and compared. The potential for incorporating sequential-AND into the language is also addressed.  相似文献   

18.
19.
The paper presents a novel precision matrix modeling technique for Gaussian Mixture Models (GMMs), which is based on the concept of sparse representation. Representation coefficients of each precision matrix (inverse covariance), as well as an accompanying overcomplete matrix dictionary, are learned by minimizing an appropriate functional, the first component of which corresponds to the sum of Kullback-Leibler (KL) divergences between the initial and the target GMM, and the second represents the sparse regularizer of the coefficients. Compared to the existing, alternative approaches for approximate GMM modeling, like popular subspace-based representation methods, the proposed model results in notably better trade-off between the representation error and the computational (memory) complexity. This is achieved under assumption that the training data in the recognition system utilizing GMM have an inherent sparseness property, which enables application of the proposed model and approximate representation using only one dictionary and a significantly smaller number of coefficients. Proposed model is experimentally compared with the Subspace Precision and Mean (SPAM) model, a state of the art instance of subspace-based representation models, using both the data from a real Automatic Speech Recognition (ASR) system, and specially designed sets of artificially created/synthetic data.  相似文献   

20.
This paper describes the design of a Prolog machine architecture and organization. Our objective was to determine the maximum performance attainable by a sequential Prolog machine for “reasonable” cost. The paper compares the organization to both general purpose micro-coded machines and reduced instruction set machines. Hand timings indicate a peak performance rate of 450 K LIPS (logical inferences per second) is well within current technology limitations and 1 M LIPS is potentially feasible.  相似文献   

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