In this paper, we introduced a method to approximate data on domain of fuzzy attributes in relation of fuzzy databases based hedge algebra. Because, domain of fuzzy attributes can except values are number, linguistic values, thus we have to effect and simply on method to approximate data. | ’ Tap ch´ Tin hoc v` Diˆu khiˆn hoc, , (2007), 110–121 ı e e . . a ` . ’ ´ ´ ’ ˜. ˆ ˆ ´ ˆ ˆ ˆ ˆ MOT CACH TIEP CAN DE XAP XI DU LIEU . . . . ’ . ˜. ˆ . ` TRONG CO SO DU LIEU MO . ˜ ` ˜ ˆ ´ ˆ ˆ ˆ ` NGUYEN CAT HO1 , NGUYEN CONG HAO2 1 Viˆn e . Cˆng nghˆ thˆng tin, Viˆn Khoa hoc v` Cˆng nghˆ Viˆt Nam o e o e e e . . . a o . . 2 .`.ng Dai hoc Khoa hoc Huˆ ´ Tru o e . . . Abstract. In this paper, we introduced a method to approximate data on domain of fuzzy attributes in relation of fuzzy databases based hedge algebra. Because, domain of fuzzy attributes can except values are number, linguistic values, thus we have to effect and simply on method to approximate data. ´ ´ ` T´m t˘t. B`i b´o tr` b`y mˆt ph´p xˆp xı d˜. liˆu trˆn miˆn tri thuˆc t´ m`. cua mˆt o a a a ınh a o a a ’ u e e e o ınh o ’ o . . . . . ’ ´ ’ u e ’ ’ ı ` ’ e o . e o ınh o o e a quan hˆ trong co. so. d˜. liˆu m`. trˆn dai sˆ gia tu v` miˆn tri cua thuˆc t´ m`. c´ thˆ l` e o . . . . . ` o o ´ ´ o u a gi´ tri sˆ , gi´ tri ngˆn ng˜., do d´ ch´ ng ta cˆn c´ mˆt ph´p xˆp xı d˜. liˆu mˆt c´ch a . o a . o u a a ’ u e o a . . . ’ ’ gian v` hiˆu qua. a e . ´ ˘ ˆ ˆ E 1. DAT VAN D` . ` a ’ ’ u e o a e a a o a e u a a Co. so. d˜. liˆu m`. d˜ nhiˆu t´c gia trong v` ngo`i nu.´.c quan tˆm nghiˆn c´.u v` d˜ . . .ng kˆt qua d´ng kˆ ([1–5, 10, 12]). C´ nhiˆu c´ch tiˆp cˆn kh´c nhau nhu. c´ch tiˆp ´ ´ ` ´ . ’ a e a e c´ nh˜ o u e’ o e a e a a . ([1]), theo l´ thuyˆt kha n˘ng ([4]) Prade v` Testemale n˘m 1983, ´ ´ . ’ a y e a a cˆn theo l´ thuyˆt tˆp m` a y e a o . ` ´ ´ ´ ´ . quan hˆ ([2, 3, 5]). Tˆ t ca c´c c´ch tiˆp cˆn trˆn nh˘ m muc d´ n˘m b˘t v` xu. e a ’ a a e a e a ıch a a a ’ . . ’ l´ mˆt c´ch thoa d´ng trˆn mˆt luˆn diˆ m n`o d´ c´c thˆng tin khˆng ch´ x´c (unexact), y o a a e o a e’ a o a o o ınh a . . . ´c ch˘n (uncertainty) hay nh˜.ng thˆng tin khˆng dˆy du (incomplete). Do su. da ´ ` ’ a o o khˆng ch˘ o a a u . ’ ´ ’ a nh˜.ng loai thˆng
