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[in Japanese]
Article type: Preface
1995 Volume 10 Issue 2 Pages
165
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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[in Japanese], [in Japanese], [in Japanese]
Article type: Cover article
1995 Volume 10 Issue 2 Pages
166-167
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Toshiyuki TAKEZAWA, Hiroshi SUEMATSU
Article type: Special issue
1995 Volume 10 Issue 2 Pages
168-180
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Satoshi NAKAMURA, Kenji KITA, Masaaki NAGATA
Article type: Special issue
1995 Volume 10 Issue 2 Pages
181-188
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Kenji KITA, Satoshi NAKAMURA, Masaaki NAGATA
Article type: Special issue
1995 Volume 10 Issue 2 Pages
189-196
Published: March 01, 1995
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Takehito UTSURO, Yuji MATSUMOTO
Article type: Special issue
1995 Volume 10 Issue 2 Pages
197-204
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Ikuo KUDO, Naomi INOUE
Article type: Special issue
1995 Volume 10 Issue 2 Pages
205-212
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Ichiro OHSAWA, Hideyuki NAKASHIMA
Article type: Technical paper
1995 Volume 10 Issue 2 Pages
222-231
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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It is difficult to describe in advance all changes which are caused by an action, because the kind of changes that are brought about depends on the situation in which the action occurs. This problem is known as the ramification problem. As a solution to the problem, we introduce an idea of "causal chains of primitive changes", and formalize the changes caused by an action as the union of the primitive changes in a causal chain. Our final goal is to program an autonomous agent. Thus, we assume here that the initial primitive change in a causal chain is an internal change, such as attempting to step ahead, of the autonomous agent. Causality is defined as a set of causal relations, and each causal relation represents that when a certain pattern of change emerges in a situation of a certain type, another pattern of change also emerges at the moment. Therefore, the causal history of primitive changes does not affect what primitive changes are caused next. As a result, less definitions of causal relations are necessary to deal with many phenomena in our framework. Moreover, as a solution to the qualification problem - the difficulty in describing the condition of each action which makes it succeed - we extend our formalism by introducing non-monotonicity to the definition of causal relations using the hierarchy of situation types. That is, the definitions of causality in a common situation do not require any rigid specifications of their pre-situation type. On the other hand, the definitions of causality in an exceptional situation must specify how the situation is exceptional. Then, the former definitions are effective in the common situation, while the latter inhibit the former in the exceptional situation.
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Tomohiro NAKATANI, Hiroshi G. OKUNO, Takeshi KAWABATA
Article type: Technical paper
1995 Volume 10 Issue 2 Pages
232-241
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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We propose a new approach to the sound stream segregation based on the multi-agent paradigm. The sound stream segregation is a technology to extract individual sounds from a mixed sound. And it is considered as a building block for Auditory Scene Analysis, which provides a mechanism of understanding the acoustic environment. But it is difficult to completely analyze all the sounds in the real world. Instead, we propose the emergent computational model as a framework to actively process focused sounds. In this paper, we discuss stream segregation agents that focus harmonics. First, we explain a basic framework, in which each tracer agent extracts a sound using local information, and these agents interact to resolve sound overlaps. Next, we construct an advanced system by introducing new agents that control the actions of tracer agents. Experimental results show that the proposed system segregates sound streams stably and adaptively to the change of the input sound.
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Naohiko URAMOTO
Article type: Technical paper
1995 Volume 10 Issue 2 Pages
242-249
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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This paper describes a method for robust disambiguation system using example-base. To improve the coverage of the example-base, three methods are introduced. First, a disambiguated thesaurus is constructed using parallel dictionary definitions. Second, conjunctive relationships are acquired from corpora, as measures of word similarity that can be used in addition to thesauruses. Third, for a word that does not appear in an example-base or a thesaurus, links to words in the example-base can be inferred by comparing the usage of the word in the text and that of words in the example-base.
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Yoshio NAKATANI, Makoto TSUKIYAMA, Toyoo FUKUDA
Article type: Technical paper
1995 Volume 10 Issue 2 Pages
250-261
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Engineering design process requires the designers' previous experiences. The designers may be required to modify basic product units as well as install new functions. It is central to creative design that the designs of other designers can be reused. We propose a case-based design support framework to support this process. Our framework is implemented as a prototype system SUPPORT, which interactively supports the design process involving the specification analysis step of making a complete specification table, the functional design step of developing each specification item into a hierarchical function tree through the use of the graphic editor, and the device selection and layout step of realizing the functions. The designers can analogically reuse past designs and/or the pieces of their own and other designers from various viewpoints. To support this reuse, we consider the semantic memory which defines the relations among concepts from the viewpoint of situations in which they are used. At the end of each step, constraint violations are checked. If some constraints are violated, the system and the user interactively try to recover them based on similar violations in the past. After a new design is completed, the functional design is organized into an existing MOPs-like function abstraction hierarchy and can be used as a framework for a new design in the future. We are currently evaluating our framework by applying SUPPORT to the design of elevator control.
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Yasuhiro NISHII, Susumu YAMASAKI
Article type: Technical paper
1995 Volume 10 Issue 2 Pages
262-270
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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The SLDNF resolution (SLD resolution with negation as failure) is often restricted to yield a safe rule, that is, negation as failure rule is adopted only the case the selected negative literal in each goal should be in ground. To investigate the application of SLDNF resolution to the case of selecting non-ground negative literals, we deal with the success and failure sets by non-safe SLDNF resolution as well as its mathematical property. Since Shepherdson's proposal is thought of as most general [Shepherdson 85], we firstly formulate Shepherdson's SLDNFS refutation as the relation on the set of goals and the set of answers, and his finite failure deduction as the relation on the set of goals. Then, as the purpose of the paper, we characterize the denotation of the success and failure sets by the SLDNF resolution with a fixpoint semantics, which is generalized to be concerned with atom sets the variables occur in. For the purpose, we show the pair of success and failure sets is included in the least fixpoint of a given general logic program. The inclusion is regarded as a generalization of the equivalance between the success set and the least fixpoint semantics for a set of definite clauses. Also the inclusion should be shown in non-ground atom set version, extending the abstract interpretation of the success and failure sets with respect to the least fixpoint in the ground version.
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Akira ITO, Hiroyuki YANO
Article type: Technical paper
1995 Volume 10 Issue 2 Pages
271-278
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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The social sanction mechanism against unfair deals is investigated in a society of autonomous agents. The mechanism is realized by disclosing the contract histories of all the agents. To simulate the situation, each agent is made to engage in the deal equivalent to the "Prisoner's dilemma" problem repetitively, each time changing the other party of the deal. Optimal deal strategies are searched under the condition that the contract records will be disclosed and open to all the agents. Several deal algorithms are taken up, and their behaviors are investigated by matching them under various conditions. Based on the results, the condition for optimal deal strategies of the agents are discussed.
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Masahiko TSUKAMOTO, Shojiro NISHIO
Article type: Technical paper
1995 Volume 10 Issue 2 Pages
279-287
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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The inheritance systems based on the concepts of IS-A relations and inheritance play central roles in many knowledge-base systems and programming systems. However, it has been shown that they are insufficient both in the expressive capability and in the reasoning capability. In order to cover these deficiencies, the authors have proposed a family of DOT systems, in which dot notations are introduced as the domain of IS-A relations. In this paper, first we discuss that the set of inference rules in each DOT system is semantically incomplete, that is, the reasoning capability is insufficient as compared with its expressive capability. Then, we provide the semantics of DOT_c which is an extension of these DOTs, and give a complete set of inference rules for the semantics. Due to such an extension, we make the expressive power of the system more complete and powerful, and as the result we demonstrate that the reasoning capability has equivalent power to its expressive capability. Moreover, we show that this new complete system has several advanced reasoning capabilities such as set-oriented query answering, polynomial time decidability, and efficient updates of knowledge, which are useful in many practical applications.
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Masahiko TSUKAMOTO, Shojiro NISHIO
Article type: Technical paper
1995 Volume 10 Issue 2 Pages
288-297
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Although the concepts of IS-A relation and inheritance are used in a wide variety of areas in computer science, it has been pointed out that their semantics as well as their expressive and reasoning capabilities lack mathematical foundation. In this paper, we propose a framework for knowledge representation and reasoning, called DOT, whose two main components are dot notations and IS-A relations. In DOT, roles or attributes are semantically included in the domain of IS-A relation using dot notations, and then relationships between objects are represented by a description of IS-A relation between two dot notations. We formalize the DOT framework in an algebraic way, and show that the upper and/or the lower bounds of each element in the domain concerning the IS-A relation can be represented by regular expressions in automata theory. Furthermore, it is proved that whether a pair of elements in the domain is included in the IS-A relation specified by the DOT framework is decided in polynomial time. In this way, the expressive and reasoning capabilities of IS-A relation and inheritance are mathematically well formalized without losing simplicity of the framework.
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Teruaki ITO, Shuichi FUKUDA
Article type: Technical paper
1995 Volume 10 Issue 2 Pages
298-305
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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This paper describes the perspective model based on Design Axiom theory, the Hypergraph model to implement the perspective model on a graphical user interface (GUI) and the prototype system HYDRA based on these models. The objective of the research is to build a design support system with GUI having a browsing function. Since a user observes a design object from a layered view point with a dynamic manner, we propose a perspective model that supports the view and the manner. The design object is based on Design Axiom theory, which will be introduced in this paper with some examples. To implement the perspective model on GUI and enable the browsing for a design, a new idea of Hypergraph is applied. A prototype system HYDRA is implemented based on these models. A design example using browsing functions of HYDRA is shown to clarify these models. HYDRA presents a new environment for a creative thinking for designs.
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Norifumi MIZUNO, Toru ISHIDA
Article type: Corner article
1995 Volume 10 Issue 2 Pages
306-313
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Real-time search algorithms determine the next move of the problem solver in a constant time and execute that move immediately. The problem solver eventually reaches the goal by repeating the cycle of planning and execution. Real-time search algorithms have some learning ability. For example, through repeated trials of LRTA, a wellknown real-time search algorithm, the estimated distances converge to the exact distances along the optimal path. In the earlier work on real-time search algorithms, however, the efficiencies of a single problem solving trial have been investigated. The purpose of this paper is to evaluate the learning efficiencies of multiple problem solving trials. The major obtained results are as follows. 1) The learning efficiencies of RTA and LRTA are first compared. When solving a problem once, RTA is superior to LRTA. When the problem is solved many times, however, LRTA becomes more efficient. 2) The learning efficiencies of different heuristic functions are then compared. In off-line search, more informative heuristic functions result more efficient problem solving performance. In real-time search, however, more informative heuristic functions improve the efficiency of the convergence through multiple problem solving processes. 3) Finally, the learning efficiencies of LRTA and LCM, the extension of LRTA to perform the locally optimal decisions, are examined. Compared with LRTA, LCM needs less execution time and more planning time. Namely there exists a trade-off between execution and planning.
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[in Japanese]
Article type: Other
1995 Volume 10 Issue 2 Pages
314
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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[in Japanese]
Article type: Corner article
1995 Volume 10 Issue 2 Pages
315-317
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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[in Japanese]
Article type: Corner article
1995 Volume 10 Issue 2 Pages
317-321
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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[in Japanese]
Article type: Corner article
1995 Volume 10 Issue 2 Pages
322
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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[in Japanese]
Article type: Corner article
1995 Volume 10 Issue 2 Pages
323
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Article type: Corner article
1995 Volume 10 Issue 2 Pages
324
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Article type: Activity report
1995 Volume 10 Issue 2 Pages
325
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Article type: Activity report
1995 Volume 10 Issue 2 Pages
326-328
Published: March 01, 1995
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Article type: Activity report
1995 Volume 10 Issue 2 Pages
329-330
Published: March 01, 1995
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Article type: Activity report
1995 Volume 10 Issue 2 Pages
b001-b016
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Article type: Cover page
1995 Volume 10 Issue 2 Pages
c002
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Article type: Cover page
1995 Volume 10 Issue 2 Pages
c002_2
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Article type: Table of contents
1995 Volume 10 Issue 2 Pages
i002
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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Article type: Table of contents
1995 Volume 10 Issue 2 Pages
i002_2
Published: March 01, 1995
Released on J-STAGE: September 29, 2020
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