Anul LII                                                                                                                                                                                                                                                                   2007

 

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

 

 

Simion Breaz and Cosmin Pelea, Professor Grigore C˘alug˘ areanu

at his 60 th anniversary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .                 3

 

N. Both, For a Completive Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .      9

 

Zhao Changjian, Wing-Sum Cheung and Mih´ aly Bencze, On Analogs

of the Dual Brunn-Minkowski Inequality for Width-Integrals of Convex

Bodies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .                13

 

Rodica Covaci, Projectors in Finite ˇ-Solvable Groups and Associated

Primitive Classes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .                    23

 

Anca Croitoru, Lebesgue Type Convergence Theorems . . . . . . . . . . . . . . . . . . . . . . .               39

 

Veronica Ana Ilea, Note on the Existence of the Solutions for Functional

Differential Equations of Mixed Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .                      51

 

Andrei Marcus, Restriction to Subgroups and Separability . . . . . . . . . . . . . . . . . . . .                 57

 

Bogdan-Gh. Munteanu, The Ergodicity Property of the Lifetime and

Ergodic Exit Times in Birth and Death Process . . . . . . . . . . . . . . . . . . . . . . . . .                           65

 

Horatiu Olaru, Cosmin Pelea and Ioan Purdea, On the Completeness

of the Semihypergroups Associated to Binary Relations . . . . . . . . . . . . . . . . .                          73

 

Monica Purcaru, On the Integrability of a Symplectic Structure on Tangent

Bundle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .                 87

 

Somogyi Ildiko, Almost Optimal Cubature Formulas with Regard

to the Efficiency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .                  99

 

Alexandrina Alina Tarta, Functional-Differential Equation with Retarded

Argument . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .                                       109

 

Claudia Timofte, On the Homogenization of a Climatization Problem . . . . . . .                     117

 

Horiana Tudor, New Univalence Criteria . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .               127

 

Dumitru Valcan, Indecomposable Subgroups of Torsion-Free Abelian

Groups . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .                   133

 

Book Reviews . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .    141