@journaltitle: MATHEMATICA BOHEMICA
@ISSN: 0862-7959
@year: 1995
@volume: 120
@issue: 4
@remark: 

@EOH
 

@author: Ji\v{r}\'{\i} Neustupa
@affiliation: {\it Ji\v{r}\'{\i} Neustupa}, Czech Technical University, Faculty of Mechanical Engineering, Department of Technical Mathematics, Karlovo n\'am. 13, 121\,35 Praha 2, e-mail: {\tt neustupa@fsid.cvut.cz} 
@title: A principle of linearization in theory of stability\newline of solutions of variational inequalities
@language: English
@pages: 337-345
@classification1: 34D05, 34G99, 58E35 
@classification2: 
@keywords: stability, variational inequalities 
@abstract: It is shown that the uniform exponential stability and the uniform stability at permanently acting disturbances of a sufficiently smooth but not necessarily steady-state solution of a general variational inequality is a consequence of the uniform exponential stability of a zero solution of another (so called linearized) variational inequality. 
@filename: neustupa

@EOI
 

@author: Franti\v{s}ek Knofl\'{\i}\v{c}ek
@affiliation: {\it Franti\v{s}ek Knofl\'{\i}\v{c}ek}, Department of Mathematics of the Faculty of Mechanical Engineering, Technical University, Technick\'a~2, 616\,69 Brno, Czech Republic 
@title: A combinatorial approach to the known\newline projective planes of order nine
@language: English
@pages: 347-366
@classification1: 51E15 
@classification2: 
@keywords: finite projective plane, ternary ring, incidence matrix, system of orthogonal Latin squares, Hall plane of order 9, Hughes plane of order 9 
@abstract: A combinatorial characterization of finite projective planes using strongly canonical forms of incidence matrices is presented. The corresponding constructions are applied to known projective planes of order 9. As a result a new description of the Hughes plane of order nine is obtained. 
@filename: knoflik

@EOI
 

@author: Ji\v{r}\'{\i} Nov\'ak
@affiliation: {\it Ji\v{r}\'{\i} Nov\'ak}, H\'alkova 1264/1, 460\,01 Liberec~I, Czech Republic 
@title: Packings of pairs with a minimum known number\newline of quadruples
@language: English
@pages: 367-377
@classification1: 05B40, 05B05 
@classification2: 
@keywords: packing of pairs with quadruples, system of quadruples, configuration, packing of $K_4$'s into $K_n$. 
@abstract: Let $E$ be an $n$-set. The problem of packing of pairs on $E$ with a minimum number of quadruples on $E$ is settled for $n<15$ and also for $n=36t+i$, $i=3$, $6$, $9$, $12$, where $t$ is any positive integer. In the other cases of $n$ methods have been presented for constructing the packings having a minimum known number of quadruples. 
@filename: novak

@EOI
 

@author: J\'an Jakub\'\i k
@affiliation: {\it J\'an Jakub\'\i k}, Matematick\'y \'ustav SAV, dislokovan\'e pracovisko, Gre\-\v s\'a\-ko\-va 6, 040\,01 Ko\v sice, Slovakia 
@title: On sequences in vector lattices
@language: English
@pages: 379-385
@classification1: 46A40, 40A05 
@classification2: 
@keywords: vector lattice, $o$-convergence, archimedean property 
@abstract: In this paper we investigate conditions for a system of sequences of elements of a vector lattice; analogous conditions for systems of sequences of reals were studied by D.\,E.\,Peek. 
@filename: jakub3

@EOI
 

@author: Alena Van\v zurov\'a
@affiliation: {\it Alena Van\v zurov\'a,} Department of Algebra and Geometry, Palack\'y University, Tom\-kova 40, 770\,00 Olomouc, e-mail {\tt vanzurov\@risc.upol.cz} 
@title: On torsion of a 3-web
@language: English
@pages: 387-392
@classification1: 53C05 
@classification2: 
@keywords: distribution, projector, manifold, connection, web 
@abstract: A 3-web on a smooth $2n$-dimensional manifold can be regarded locally as a triple of integrable $n$-distributions which are pairwise complementary, [5]; that is, we can work on the tangent bundle only. This approach enables us to describe a $3$-web and its properties by invariant $(1,1)$-tensor fields $P$ and $B$ where $P$ is a projector and $B^2=$ id. The canonical Chern connection of a web-manifold can be introduced using this tensor fields, [1]. Our aim is to express the torsion tensor $T$ of the Chern connection through the Nijenhuis $(1,2)$-tensor field $[P,B]$, and to verify that $[P,B]=0$ is a necessary and sufficient conditions for vanishing of the torsion $T$. 
@filename: van7

@EOI
 

@author: Janina Ewert
@affiliation: {\it Janina Ewert,} Department of Mathematics, Pedagogical University, Arciszewskiego~22b, 76--200 S\l upsk, Poland 
@title: Quasicontinuity and related properties\newline of functions and multivalued maps
@language: English
@pages: 393-403
@classification1: 54C08, 54C60, 26A25 
@classification2: 
@keywords: uniform space, multivalued map, quasicontinuity 
@abstract: The main results presented in this paper concern multivalued maps. We consider the cliquishness, quasicontinuity, almost continuity and almost quasicontinuity; these properties of multivalued maps are characterized by the analogous properties of some real functions. The connections obtained are used to prove decomposition theorems for upper and lower quasicontinuity. 
@filename: ewert

@EOI
 

@author: Bohdan Zelinka
@affiliation: {\it Bohdan Zelinka,} katedra diskr\'etn\'{\i} matematiky a statistiky Technick\'e university, Voron\v{e}\v{z}sk\'a 13, 461\,17 Liberec 
@title: Domination in graphs with few edges
@language: English
@pages: 405-410
@classification1: 05C35 
@classification2: 
@keywords: domination number, signed domination number, minus domination number. 
@abstract: The domination number $\g(G)$ of a graph $G$ and two its variants are considered, namely the signed domination number $\g_s (G)$ and the minus domination number $\g^-(G)$. These numerical invariants are compared for graphs in which the degrees of vertices do not exceed 3. 
@filename: zel11

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@author: Tom\'{a}\v{s} Roub\'{\i}\v{c}ek
@affiliation: {\it Tom\'{a}\v{s} Roub\'{\i}\v{c}ek,} Mathematical Institute of the Charles University, Sokolovsk\'a~83, CZ-186\,00 Praha~8, Czech Republic, and Institute of Information Theory and Automation, Academy of Sciences of the Czech Republic, Pod vod\'{a}renskou v\v{e}\v{z}\'{\i}~4, CZ-182\,08 Praha~8, Czech Republic, e-mail: {\tt roubicek@karlin.mff.cuni.cz} 
@title: Relaxation of vectorial variational problems
@language: English
@pages: 411-430
@classification1: 49K99, 49J99, 73V25, 35D05 
@classification2: 
@keywords: relaxed variational problems, Young measures, minors of gradients, optimality conditions, Weierstrass-type maximum principle 
@abstract: Multidimensional vectorial non-quasiconvex variational problems are relaxed by means of a generalized-Young-functional technique. Selective first-order optimality conditions, having the form of an Euler-Weiestrass condition involving minors, are formulated in a special, rather a model case when the potential has a polyconvex quasiconvexification. 
@filename: roubicek

@EOI
 

@author: Shigenori Yanagi
@affiliation: {\it Shigenori Yanagi}, Department of Mathematics, Faculty of Science, Ehime University, Matsuyama 790, Japan, e-mail: {\tt syanagi@dpcsipc.dpc.ehime-u.ac.jp} 
@title: Asymptotic behavior of the solutions\newline to a one-dimensional motion\newline of compressible viscous fluids
@language: English
@pages: 431-443
@classification1: 35Q30, 76N10, 76N15 
@classification2: 
@keywords: compressible viscous gas, asymptotic behaviour of the solutions 
@abstract: We study the one-dimensional motion of the viscous gas represented by the system $v_{t}-u_{x} = 0$, $ u_{t}+ p(v)_{x} = \mu(u_{x}/v)_{x} + f \left( \int_0^xv\dd x,t \right)$, with the initial and the boundary conditions $(v(x,0), u(x,0)) = (v_{0}(x), u_{0}(x))$, $u(0,t) = u(X,t) = 0$. We are concerned with the external forces, namely the function $f$, which do not become small for large time $t$. The main purpose is to show how the solution to this problem behaves around the stationary one, and the proof is based on an elementary $L^{2}$-energy method. 
@filename: yanagi

@EOI
 

@author: Bohdan Zelinka
@affiliation: {\it Bohdan Zelinka}, katedra diskr\'etn\'{\i} matematiky a statistiky Technick\'e university, Voron\v{e}\v{z}sk\'a 13, 460\,01 Liberec 
@title: Subtraction semigroups
@language: English
@pages: 445-447
@classification1: 20M20, 06E05 
@classification2: 
@keywords: subtraction semigroup, subtraction algebra, Boolean algebra 
@abstract: A subtraction semigroup is a semigroup $(A,\ldotp,-)$ with a further operation ``$-$'' added, called subtraction and satisfying certain axioms. The paper concerns a problem by B.\,M.~Schein concerning the structure of multiplication in a subtraction semigroup. 
@filename: zeli2

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