• Title/Summary/Keyword: enumeration arrangement

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COMBINATORIAL ENUMERATION OF THE REGIONS OF SOME LINEAR ARRANGEMENTS

  • Seo, Seunghyun
    • Bulletin of the Korean Mathematical Society
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    • v.53 no.5
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    • pp.1281-1289
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    • 2016
  • Richard Stanley suggested the problem of finding combinatorial proofs of formulas for counting regions of certain hyperplane arrangements defined by hyperplanes of the form $x_i=0$, $x_i=x_j$, and $x_i=2x_j$ that were found using the finite field method. We give such proofs, using embroidered permutations and linear extensions of posets.

A Study on Brown's Subject Classification (브라운의 주제분류법 연구)

  • Kwak, Chul-Wan
    • Journal of the Korean Society for information Management
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    • v.35 no.4
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    • pp.37-50
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    • 2018
  • The purpose of this study is to analyze the first edition of Brown's Subject Classification and to understand the implications of today's library classification. For this purpose, the first edition of the Subject Classification published in 1906 was analyzed. The analysis results are divided into three main areas. First, SC is divided into eleven main classes and each class is subdivided into enumerated subdivisions from 000 to 999. Second, As a method of synthesizing the classification numbers, there were three methods of synthesis. There was a flexibility to insert a new classification number at the appropriate location when a new topic that does not appear in the main table appeared. Implications for classification studies can be divided into four main categories. First, SC proposed a method of classification number synthesis for composite topics, which is an innovative method that was not available in previous library classification. Second, the subject matter was explained in various aspects through the operation of auxiliary tables supporting the facets. Third, it is possible to easily insert a new topic into the classification system by using the SC that can have a flexible classification system for each library, or to use a short classification number according to the size of the library collection. Fourth, it provided a directory that can be considered as access points for digital materials.