منابع مشابه
On set systems without weak 3 - A - subsystems
A collection of sets is called a weak A-system if sizes of all pairwise intersections of these sets coincide. We prove a new upper bound on the function ./~,.(n), the maximal size of a collection of n-element sets no three of which form a weak A-system. Namely, we prove that, for every 6 > 0. L,(n) = o(n!1"2 +~). We say that three sets A,B,C form a (3-)A-system if A ~ B = B c~ C = C c~ A. If a ...
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The notion of a weak ∆-system was introduced and studied by Erdős, Milner and Rado [5] in 1974. A weak ∆-system is a family of sets where all pairs of sets have the same intersection size. Erdős and Szemerédi [7] investigated the behavior of the function F (n,r)—the largest integer so that there exists a family F of subsets of an n-element set which does not contain a ∆-system of r sets. Answer...
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Background & Aims: Compliance with standards of designing information systems leads to efficient utilization and ease of use for consumers. In this study, the compliance of the radiology and pathology subsystems of a hospital information system with ISO 9241 section 12 was assessed in selected hospitals affiliated with Kerman University of Medical Sciences, Iran. Methods...
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A d-simplex is a collection of d + 1 sets such that every d of them have nonempty intersection and the intersection of all of them is empty. A strong d-simplex is a collection of d + 2 sets A,A1, . . . , Ad+1 such that {A1, . . . , Ad+1} is a d-simplex, while A contains an element of ∩j =iAj for each i, 1 ≤ i ≤ d + 1. Mubayi and Ramadurai [Combin. Probab. Comput., 18 (2009), pp. 441– 454] conje...
متن کاملSet systems without a strong simplex (revised)
A d-simplex is a collection of d + 1 sets such that every d of them have non-empty intersection and the intersection of all of them is empty. A strong d-simplex is a collection of d+ 2 sets A,A1, . . . , Ad+1 such that {A1, . . . , Ad+1} is a d-simplex, while A contains an element of ∩j 6=iAj for each i, 1 ≤ i ≤ d+ 1. Mubayi and Ramadurai [15] conjectured that if k ≥ d+1 ≥ 3, n > k(d+1)/d, and ...
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1995
ISSN: 0012-365X
DOI: 10.1016/0012-365x(94)00185-l