A theoretical model for crisp and fuzzy time

Author

Van Der Cruyssen, B. ; de Caluwe, R. ; De TrÉ, G. ; Vandycke, D.

Author_Institution

Comput. Sci. Lab., Ghent Univ., Belgium

fYear

1997

fDate

21-24 Sep 1997

Firstpage

63

Lastpage

67

Abstract

Based on the way time is expressed in natural language, as was studied in the linguistic part of our research, it is observed that time indications usually are rather approximative and situated within the context of the traditional hierarchical time unit system, thereby choosing the most appropriate level of detail. In this paper we present a model for temporal data which aims at being both as flexible and as general as possible. Flexibility is obtained by the use of fuzzy set theory and of granularities which brings the model very close to its natural language counterpart. Generality is achieved by the dynamic aspect of the granularity structure and by the support of spans, time points and intervals, absolute and relative time, aperiodic as well as periodic time elements

Keywords

data structures; database theory; fuzzy logic; fuzzy set theory; natural languages; temporal databases; temporal logic; absolute time; aperiodic time elements; crisp time; fuzzy set theory; fuzzy time; granularities; hierarchical time unit system; intervals; linguistic; natural language; periodic time elements; relative time; research; spans; temporal data model; temporal database; theoretical model; time points; Computer science; Database systems; Density estimation robust algorithm; Fuzzy set theory; Fuzzy sets; Information processing; Laboratories; Natural languages; Object oriented databases; Periodic structures;

fLanguage

English

Publisher

ieee

Conference_Titel

Fuzzy Information Processing Society, 1997. NAFIPS '97., 1997 Annual Meeting of the North American

Conference_Location

Syracuse, NY

Print_ISBN

0-7803-4078-7

Type

conf

DOI

10.1109/NAFIPS.1997.624012

Filename

624012