16 citations · 106 across the 45 of their papers we have counts for
58 papers
Time and Supply Fairness in Electricity Distribution using -times bin packing
Dinesh Kumar Baghel, Alex Ravsky, Erel Segal-Halevi
Given items of different sizes and a fixed bin capacity, the bin-packing problem is to pack these items into the minimum number of bins such that the sum of the item sizes in each…
Linear Geometry: flats, ranks, regularity, parallelity
Taras Banakh, Ivan Hetman, Alex Ravsky +1
Linear Geometry describes geometric properties that depend on the fundamental notion of a line. In this paper we survey basic notions and results of Linear Geomery that depend on t…
Steiner systems and exist
Taras Banakh, Ivan Hetman, Alex Ravsky
Via computer search, we found seven non-isomorphic -rotational Steiner systems and six point-transitive Steiner systems , resolving two of previous…
New Steiner systems with block length 6
Taras Banakh, Ivan Hetman, Alex Ravsky
In this paper various Steiner systems for are collected and enumerated for specific constructions. In particular, two earlier unknown types of -rotational des…
Enumerations of 1-rotational Steiner systems
Ivan Hetman, Taras Banakh, Alex Ravsky
In this paper new -rotational 2-Steiner systems for different admissible pairs are introduced. In particular, -rotational unitals of order are enumerated.
Point-transitive and 1-rotational unitals of order 5
Ivan Hetman, Taras Banakh, Alex Ravsky
In this paper we introduce enumeration of unitals of order , which are also Steiner systems , where automorphism group acts transitively and effectively on points or…
-times bin packing and its application to fair electricity distribution
Dinesh Kumar Baghel, Alex Ravsky, Erel Segal-Halevi
Given items of different sizes and a fixed bin capacity, the bin-packing problem is to pack these items into a minimum number of bins such that the sum of item sizes in a bin does…
Midconvex sets in Abelian groups
Iryna Banakh, Taras Banakh, Maria Kolinko +1
A subset of an Abelian group is called if for every the set is a subset of . We prove that a subset of an Abel…
Metric characterizations of some subsets of the real line
Iryna Banakh, Taras Banakh, Maria Kolinko +1
A metric space is called a if every 3-element subset of can be written as for some points such that . By a cla…
On pseudobounded and premeager paratopological groups
Taras Banakh, Alex Ravsky
Let be a paratopological group. Following F. Lin and S. Lin, we say that the group is pseudobounded, if for any neighborhood of the identity of , there exists a natu…
Semitopological modules
Taras Banakh, Alex Ravsky
Given a topological ring , we study semitopological -modules, construct their completions, Bohr and borno modifications. For every topological space , we construct the fre…
The fair soup division and approximating numbers
Alex Ravsky
We consider a recent The Vee's fair soup division problem, provide its partial solution, and pose a related open problem.
On unconditionally convergent series in topological rings
Taras Banakh, Alex Ravsky
We define a topological ring to be \emph{Hirsch}, if for any unconditionally convergent series in and any neighborhood of the additive identity o…
Suitable sets for paratopological groups
Fucai Lin, Alex Ravsky, Tingting Shi
A paratopological group has a {\it suitable set} . The latter means that is a discrete subspace of , is closed, and the subgroup of $…
A note on approximation of continuous functions on normed spaces
M. A. Mytrofanov, A. V. Ravsky
Let be a real separable normed space admitting a separating polynomial. We prove that each continuous function from a subset of to a real Banach space can be unifor…
A countably compact topological group with the non-countably pracompact square
Serhii Bardyla, Alex Ravsky, Lyubomyr Zdomskyy
Under Martin's Axiom we construct a Boolean countably compact topological group whose square is not countably pracompact.
Each topological group embeds into a duoseparable topological group
Taras Banakh, Igor Guran, Alex Ravsky
A topological group is called if there exists a countable set such that for any neighborhood of the unit. We construct a fu…
The Complexity of Finding Tangles
Oksana Firman, Philipp Kindermann, Boris Klemz +3
We study the following combinatorial problem. Given a set of y-monotone curves, which we call wires, a tangle determines the order of the wires on a number of horizontal layers…
Generalizing separability, precompactness and narrowness in topological groups
Taras Banakh, Igor Guran, Alex Ravsky
We discuss various modifications of separability, precompactnmess and narrowness in topological groups and test those modifications in the permutation groups and …
A metrizable Lawson semitopological semilattice with non-closed partial order
Taras Banakh, Serhii Bardyla, Alex Ravsky
We construct a metrizable Lawson semitopological semilattice whose partial order is not closed in . This resolves a problem posed…
Variants of the Segment Number of a Graph
Yoshio Okamoto, Alexander Ravsky, Alexander Wolff
The \emph{segment number} of a planar graph is the smallest number of line segments whose union represents a crossing-free straight-line drawing of the given graph in the plane. Th…
Closed subsets of compact-like topological spaces
Serhii Bardyla, Alex Ravsky
We investigate closed subsets (subsemigroups, resp.) of compact-like topological spaces (semigroups, resp.). We prove that each Hausdorff topological space can be embedded as a clo…
A note on compact-like semitopological groups
Alex Ravsky
The note contains a few results related to separation axioms and automatic continuity of operations in compact-like semitopological groups. In particular, is presented a semiregula…
Embeddings into countably compact Hausdorff spaces
Taras Banakh, Serhii Bardyla, Alex Ravsky
In this paper we consider the problem of characterization of topological spaces that embed into countably compact Hausdorff spaces. We study the separation axioms of subspaces of c…