http://tainguyenso.vnu.edu.vn/jspui/handle/123456789/100 Wed, 20 May 2026 20:50:35 GMT 2026-05-20T20:50:35Z http://tainguyenso.vnu.edu.vn/jspui/handle/123456789/1032 Algorithm for solution of a routing problem Tran, Vu Thieu; Pham, Xuan Hinh In this paper we consider a combinatorial optimization problem that is similar to the bottleneck traveling salesman problem. We show that an optimal tour for this problem is pyramidal tour (1, 3, 5,…, n,…, 6, 4, 2) or consists of some pyramidal subtours. The above 7methods can be extended to complete bipartite graphs. VNU Journal of Science, Mathematics - Physics. Vol. 23 (2007), No 3, P. 178-182 Mon, 01 Jan 2007 00:00:00 GMT http://tainguyenso.vnu.edu.vn/jspui/handle/123456789/1032 2007-01-01T00:00:00Z http://tainguyenso.vnu.edu.vn/jspui/handle/123456789/1029 Some laws of large numbers in non-commutative probability Nguyen, Van Quang; Nguyen, Duy Tien In this report we present some noncommutative weak and strong laws of large numbers. Two case are considered: a von Neumann algebra with a normal faithful state on it and the algebra of measurable operators with normal faithful trace. VNU Journal of Science, Mathematics - Physics. Vol. 23 (2007), No 3, P. 159-167 Mon, 01 Jan 2007 00:00:00 GMT http://tainguyenso.vnu.edu.vn/jspui/handle/123456789/1029 2007-01-01T00:00:00Z http://tainguyenso.vnu.edu.vn/jspui/handle/123456789/1025 The parameter-dependent cyclic inequality Nguyen, Vu Luong In this paper we will construct a parameter-dependent cyclic inequality that can be used to prove a lot of hard and interesting inequalities. VNU Journal of Science, Mathematics - Physics. Vol. 23 (2007), No 3, P. 155-158 Mon, 01 Jan 2007 00:00:00 GMT http://tainguyenso.vnu.edu.vn/jspui/handle/123456789/1025 2007-01-01T00:00:00Z http://tainguyenso.vnu.edu.vn/jspui/handle/123456789/1024 On the martingale representation theorem and approximate hedging a contingent claim in the minimum mean square deviation criterion Nguyen, Van Huu; Vuong, Quan Hoang In this work we consider the problem of the approximate hedging of a contingent claim in minimum mean square deviation criterion. A theorem on martingale representation in the case of discrete time and an application of obtained result for semi-continous market model are given. VNU Journal of Science, Mathematics - Physics. Vol. 23 (2007), No 3, P. 143-154 Mon, 01 Jan 2007 00:00:00 GMT http://tainguyenso.vnu.edu.vn/jspui/handle/123456789/1024 2007-01-01T00:00:00Z