Issue 2, Volume 20, December 1995

1995 · Open access

1. DANG DINH ANG: THE FIRST SEVENTY YEARS NGUYEN HUU ANH, NGUYEN XUAN SANH, TRAN DUC VAN PDF

   165-169
2. FLOWS METHOD IN GLOBAL ANALYSIS DUONG MINH DUC PDF

   ▸ Abstract

   We study the gradient flows method for $W^{r,p}(\mathcal M, \mathcal N)$, where $\mathcal M$ and $\mathcal N$ are Riemannian manifolds and $rp$ may be less than the dimension of $\mathcal M$.

   171-180
3. A NEW COMPUTATION OF TWO-DIMENSIONAL FINITE-PART INTEGRALS BUI DOAN KHANH PDF

   181-192
4. SURFACE TEMPERATURE DETERMINATION FROM BOREHOLE MEASUREMENTS: A FINITE SLAB MODEL TRAN THI LE, DINH NGOC THANH, PHAM HUU TRI PDF

   ▸ Abstract

   The authors consider the problem of determining the temperature at one surface of a slab of finite thickness from temperatures measured at interior points. The problem is reduced to solving a Cauchy problem for the heat equation, which is then regularized using the Tikhonov method. Error estimastes are given.

   193-206
5. IMPACT OF A VISCOPLASTIC ROD AGAINST AN ELASTIC OBSTACLE TRINH ANH NGOC, DANG DUC TRONG PDF

   207-218
6. FIRING SEQUENCES AND PROCESSES OF PETRI NETS DANG VAN HUNG, TRAN VAN DUNG PDF

   ▸ Abstract

   We show how an equivalence relation on the set of firing sequences of a general net can be defined so that equivalent sequences have the same set of processes. For a special class of nets, we establish a characterization of equivalence classes on firing sequences which define the same partial orders on transition occurrences as those defined by the processes. With every n-safe net we associate a 1-safe net which has, in a certain sense, the same set of processes as the initial net. For some classes of nets we obtain some kind of regular properties for the set of processes.

   219-232
7. ON ANTISIMPLE PRIMITIVE RADICAL OF $\Gamma_N$-RINGS WANG DINGGUO PDF

   ▸ Abstract

   Let $M$ be a $\Gamma$-ring and let $M_2=\begin{pmatrix} R&\Gamma\\ M &L\end{pmatrix}$, where $R$ (resp. $L$) is the right (resp. left) operator ring of $M$. In this paper we show that the class of all primitive subdirectly irreducible $\Gamma$-rings is special, and then we establish relationships between the antisimple primitive radicals of the $\Gamma$-ring $M$, the right operator ring $R$ of $M$, the matrix $\Gamma_{n,m}$-ring $M_{m,n}$, the $M$-ring $\Gamma$ and the ring $M_2$.

   233-245
8. ON HAMILTON CYCLES IN CUBIC $(10, n)$-METACIRCULANT GRAPHS NGO DAC TAN PDF

   ▸ Abstract

   We prove in this paper that every connected cubic $(10,n)$-metacirculant graph has a Hamilton cycle if $n$ is a positive integer such that $\varphi(n)$ is not divisible by 5, where $\varphi(n)$ is the number of integer $z$ satisfying $0\leq z < n$ and $gcd(z,n)=1$.

   247-255
9. ON BING'S QUESTION ABOUT FIXED POINT PROPERTY LE HOANG TRI PDF

   ▸ Abstract

   Bing [1] constructed a compactum $X$ in $\mathbb R^3$ which has the fixed point property but $X\cup D$ does not, where $D$ is a rectangle and $X\cap D$ is an interval. He also asked whether $X\times [0,1]$ has the fixed point property. In [4] Young gave a positive answer to this question. The aim of this note is to extend Young's result to the product $X\times A$ where $A$ is a compact AR-space. The result does not hold if $A$ is a compact fixed point space.

   257-264
10. MINIMIZING THE PRODUCT OF TWO DISCRETE CONVEX FUNCTIONS NGUYEN DUC NGHIA, DO DUY CHINH, PHAM CANH DUONG PDF

    ▸ Abstract

    A method for solving a discrete convex multiplicative programming (referred to as DCMP) is proposed. It is shown that DCMP can be solved by parametric discrete convex minimization. The method is specialized for the problem of minimizing the product of two discrete separable convex functions over a general supermatroid. The results of computational experiments for the last method are reported. An approximation algorithm is also proposed for solving the problem in a more general case.

    265-267
11. BIFURCATION AND HOPF BIFURCATION AT MULTIPLE EIGENVALUES FOR EQUATIONS WITH LIPSCHITZ MAPPINGS NGUYEN XUAN TAN PDF

    ▸ Abstract

    Some results on the existence of bifurcation and Hopf bifurcation at multiple eigenvalues for abstract equations concerning Lipschitz continuous mappings in Banach spaces are proved. The obtained results improve some well-known bifurcation results by Crandall and Rabinowitz, McLeod and Sattinger Hopf etc. in the case involving Lipschitz continuous mappings. Some illustrative examples are given.

    279-311
12. EXTENDING HOLOMORPHIC MAPS THROUGH PLURI-POLAR SETS IN HIGH DIMENSION DO DUC THAI PDF

    ▸ Abstract

    In this paper we prove that if a complex space $X$ has the strictly holomorphic 1-extension property through polar sets, then $X$ also has the strictly holomorphic n-extension property through pluri-polar sets for all $n\geq 2$. Moreover, some results of Suzuki and Järvi are deduced from the above-mentioned theorem.

    313-320
13. ON THE STABILITY OF THE CHARACTERIZATION OF DOUBLE-COMPOSED RANDOM VARIABLES NGUYEN HUU BAO PDF

    ▸ Abstract

    The random variable $\varsigma$ is called a composed random variable of two random variables $\xi$ and $\eta$ if its characteristic function has the form $$\psi(t)=a[\phi(t)]$$ where $a[z]$ is the generating function of $\eta$ and $\phi(t)$ is the characteristic function of $\xi$. In our previous papers, we have considered a stability condition for characteristic functions of a class of composed random variables. In this paper, we consider another condition for the characteristic function of the composed random variable of $\xi$ and $\eta$, if $\eta$ is also a composed random variable.

    321-326