Anul XLVII 2002

S T U D I A

UNIVERSITATIS BABEŞ-BOLYAI

MATHEMATICA

2

Redacţia: 400084 Cluj-Napoca, Str. M. Kogălniceanu nr. 1 Tel: 405300

SUMAR – CONTENTS – SOMMAIRE

Iluşca Bonta, Simple subalgebras of group graded algebras . . . . . . . . . . . . . . . . . . . . . .3

Daniel Breaz and Nicoleta Breaz, Univalence conditions for certain

integral operators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

Simion Breaz and Ciprian Modoi, On a quotient category . . . . . . . . . . . . . . . . . . . . . . 17

Graţiela Cicortaş, Categorical sequences and applications . . . . . . . . . . . . . . .. . . . . . . 31

Tallat El Sayed Ali El Danaf, Numerical solution of the Korteweg -

De Vries Burgers equation by using Quintic spline method . . . . . . . . . . . . . . .. . . . . . . 41

Dorina Răducanu, On uniformly convex mappings of a Banach space into the

complex plane . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 57

Dorina Răducanu and Paula Curt, An univalence condition . . . . . . . . . . . . . . . . . . . .. . 61

Milena Solomon, Cubature formulas on triangle . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . 67

Tiberiu Trif, An existence uniqueness theorem for an integral equation

modelling infectious diseases . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

Liana Ţopan, Critical and vector critical sets in the plane . . . . . . . . . . . . . . . . . . . . . . 83

Book reviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97