Bart De Bruyn, Puspendu Pradhan, Binod Kumar Sahoo
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引用次数: 0
Abstract
For a set \({\mathcal {L}}\) of lines of \(\text{ PG }(n,q)\), a set X of points of \(\text{ PG }(n,q)\) is called an \({\mathcal {L}}\)-blocking set if each line of \({\mathcal {L}}\) contains at least one point of X. Consider a possibly singular quadric Q of \(\text{ PG }(n,q)\) and denote by \({\mathcal {S}}\) (respectively, \({\mathcal {T}}\)) the set of all lines of \(\text{ PG }(n,q)\) meeting Q in 2 (respectively, 1 or \(q+1\)) points. For \({\mathcal {L}}\in \{{\mathcal {S}},{\mathcal {T}}\cup {\mathcal {S}}\}\), we find the minimal cardinality of an \({\mathcal {L}}\)-blocking set of \(\text{ PG }(n,q)\) and determine all \({\mathcal {L}}\)-blocking sets of that minimal cardinality.
期刊介绍:
Designs, Codes and Cryptography is an archival peer-reviewed technical journal publishing original research papers in the designated areas. There is a great deal of activity in design theory, coding theory and cryptography, including a substantial amount of research which brings together more than one of the subjects. While many journals exist for each of the individual areas, few encourage the interaction of the disciplines.
The journal was founded to meet the needs of mathematicians, engineers and computer scientists working in these areas, whose interests extend beyond the bounds of any one of the individual disciplines. The journal provides a forum for high quality research in its three areas, with papers touching more than one of the areas especially welcome.
The journal also considers high quality submissions in the closely related areas of finite fields and finite geometries, which provide important tools for both the construction and the actual application of designs, codes and cryptographic systems. In particular, it includes (mostly theoretical) papers on computational aspects of finite fields. It also considers topics in sequence design, which frequently admit equivalent formulations in the journal’s main areas.
Designs, Codes and Cryptography is mathematically oriented, emphasizing the algebraic and geometric aspects of the areas it covers. The journal considers high quality papers of both a theoretical and a practical nature, provided they contain a substantial amount of mathematics.