• 제목/요약/키워드: linear discrepancy

검색결과 97건 처리시간 0.023초

DISCONNECTED POSETS AND LD-IRREDUCIBLE POSETS

  • Chae, Gab-Byung;Cheong, MinSeok;Kim, Sang-Mok
    • 대한수학회논문집
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    • 제36권1호
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    • pp.189-196
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    • 2021
  • Using ld-irreducible posets, we can easily characterize posets with respect to linear discrepancy. However, it is difficult to have the list of all the irreducible posets with respect to a given linear discrepancy. In this paper, we investigate some properties of disconnected posets and connected posets with respect to linear discrepancy, respectively and then we find various relationships between ld-irreducibily and connectedness. From these results, we suggest some methods to construct ld-irreducible posets.

A CHARACTERIZATION OF n-POSETS OF LD n - k WITH SIMPLE POSETS

  • Chae, Gab-Byung;Cheong, Minseok;Kim, Sang-Mok
    • 대한수학회보
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    • 제55권3호
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    • pp.777-788
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    • 2018
  • A simple poset is a poset whose linear discrepancy increases if any relation of the poset is removed. In this paper, we investigate more important properties of simple posets such as its width and height which help to construct concrete simple poset of linear discrepancy l. The simplicity of a poset is similar to the ld-irreducibility of a poset. Hence, we investigate which posets are both simple and ld-irreducible. Using these properties, we characterize n-posets of linear discrepancy n - k for k = 2, 3, and, lastly, we also characterize a poset of linear discrepancy 3 with simple posets and ld-irreducible posets.

THE LINEAR DISCREPANCY OF A PRODUCT OF TWO POSETS

  • Cheong, Minseok
    • 대한수학회보
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    • 제54권3호
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    • pp.1081-1094
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    • 2017
  • For a poset $P=(X,{\leq}_P)$, the linear discrepancy of P is the minimum value of maximal differences of all incomparable elements for all possible labelings. In this paper, we find a lower bound and an upper bound of the linear discrepancy of a product of two posets. In order to give a lower bound, we use the known result, $ld({\mathbf{m}}{\times}{\mathbf{n}})={\lceil}{\frac{mn}{2}}{\rceil}-2$. Next, we use Dilworth's chain decomposition to obtain an upper bound of the linear discrepancy of a product of a poset and a chain. Finally, we give an example touching this upper bound.

THE LINEAR DISCREPANCY OF 3 × 3 × 3

  • Chae, Gab-Byoung;Cheong, Min-Seok;Kim, Sang-Mok
    • 대한수학회논문집
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    • 제25권1호
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    • pp.19-25
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    • 2010
  • $3{\times}3{\times}3$ is the meaningful smallest product of three chains of each size 2n+1 since $1{\times}1{\times}1$ is a 1-element poset. The linear discrepancy of the product of three chains $2n{\times}2n{\times}2n$ is found as $6n^3-2n^2-1$. But the case of the product of three chains $(2n + 1){\times}(2n + 1){\times}(2n + 1)$ is not known yet. In this paper, we determine ld$(3{\times}3{\times}3)$ as a case to determine the linear discrepancy of the product of three chains of each size 2n + 1.

The Linear Discrepancy of a Fuzzy Poset

  • Cheong, Min-Seok;Chae, Gab-Byung;Kim, Sang-Mok
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제11권1호
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    • pp.59-64
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    • 2011
  • In 2001, the notion of a fuzzy poset defined on a set X via a triplet (L, G, I) of functions with domain X ${\times}$ X and range [0, 1] satisfying a special condition L+G+I = 1 is introduced by J. Negger and Hee Sik Kim, where L is the 'less than' function, G is the 'greater than' function, and I is the 'incomparable to' function. Using this approach, we are able to define a special class of fuzzy posets, and define the 'skeleton' of a fuzzy poset in view of major relation. In this sense, we define the linear discrepancy of a fuzzy poset of size n as the minimum value of all maximum of I(x, y)${\mid}$f(x)-f(y)${\mid}$ for f ${\in}$ F and x, y ${\in}$ X with I(x, y) > $\frac{1}{2}$, where F is the set of all injective order-preserving maps from the fuzzy poset to the set of positive integers. We first show that the definition is well-defined. Then, it is shown that the optimality appears at the same injective order-preserving maps in both cases of a fuzzy poset and its skeleton if the linear discrepancy of a skeleton of a fuzzy poset is 1.

입력 불일치 해소에 의한 개선형 무충돌전환 (An Improved Bumpless Transfer by Solving the Input Discrepancy Problem)

  • 김태신;양지혁;권태완;권오규
    • 제어로봇시스템학회논문지
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    • 제15권10호
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    • pp.982-987
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    • 2009
  • On the controller switching time, even though on-line/off-line controller outputs are the same, a problem which deteriorates the performance of bumpless transfer can happen in case that any discrepancy between the two controller inputs is transferred directly to the controller output. In this paper, we analyze the cause of that phenomenon in existing research results and propose a new method which improves that problem. In order to solve this problem, the off-line controller is augmented to an anti-windup structure and an improved bumpless transfer method is derived by using the changed input of the off-line controller instead of the plant input. We exemplify the performance of the proposed method by comparing with the performance of the existing method via numerical examples.

Diagnostics for Regression with Finite-Order Autoregressive Disturbances

  • Lee, Young-Hoon;Jeong, Dong-Bin;Kim, Soon-Kwi
    • Journal of the Korean Statistical Society
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    • 제31권2호
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    • pp.237-250
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    • 2002
  • Motivated by Cook's (1986) assessment of local influence by investigating the curvature of a surface associated with the overall discrepancy measure, this paper extends this idea to the linear regression model with AR(p) disturbances. Diagnostic for the linear regression models with AR(p) disturbances are discussed when simultaneous perturbations of the response vector are allowed. For the derived criterion, numerical studies demonstrate routine application of this work.

ENUMERATION OF OPTIMALLY LABELLED GRAPHS OF BANDWIDTH 2

  • Chae, Gab-Byung;Cheong, MinSeok;Kim, Sang-Mok
    • 대한수학회보
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    • 제54권6호
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    • pp.1883-1891
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    • 2017
  • An optimally labelled graph of bandwidth 2 is an ordered pair (G, f) where G is a simple graph with bw(G) = 2 and $f:V(G){\rightarrow}[n]$ is a bijection such that bw(G, f) = 2. In this paper, the number of optimally labelled graphs of bandwidth two of order n is enumerated by counting linear forests.

리니어모터 이송시스템의 2축제어특성에 관한 연구 (Two axis control characteristics of linear motor feed system)

  • 유송민;신관수
    • 한국공작기계학회:학술대회논문집
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    • 한국공작기계학회 2002년도 추계학술대회 논문집
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    • pp.405-410
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    • 2002
  • Linear motor food system control algorithm was extended to the two axis system. Among several factors considered, overshoot of the response was the most important one in minimizing position tracking error. Balance between overshoot and settling time has to be adjusted to guarantee to best tracking performance. Tracking route was carefully executed to eliminate the possible error during the machining process. Even though there exists slight discrepancy between desired mute and cutting track at the corner, precision machining could be implemented using the cutting scheme introduced.

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