• 제목/요약/키워드: Set Packing

검색결과 107건 처리시간 0.022초

A study on the column subtraction method applied to ship scheduling problem

  • Hwang, Hee-Su;Lee, Hee-Yong;Kim, Si-Hwa
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2004년도 춘계학술대회 논문집
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    • pp.401-405
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    • 2004
  • Column subtraction, originally proposed by Harche and Thompson(]994), is an exact method for solving large set covering, packing and partitioning problems. Since the constraint set of ship scheduling problem(SSP) have a special structure, most instances of SSP can be solved by LP relaxation. This paper aims at applying the column subtraction method to solve SSP which can not be solved by LP relaxation. For remained instances of unsolvable ones, we subtract columns from the finale simplex table to get another integer solution in an iterative manner. Computational results having up to 10,000 0-1 variables show better performance of the column subtraction method solving the remained instances of SSP than complex branch-and-bound algorithm by LINDO.

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A study on the column subtraction method applied to ship scheduling problem

  • Hwang, Hee-Su;Lee, Hee-Yong;Kim, Si-Hwa
    • 한국항해항만학회지
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    • 제28권2호
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    • pp.129-133
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    • 2004
  • Column subtraction, originally proposed by Harche and Thompson(1994), is an exact method for solving large set covering, packing and partitioning problems. Since the constraint set of ship scheduling problem(SSP) have a special structure, most instances of SSP can be solved by LP relaxation This paper aim, at applying the column subtraction method to solve SSP which am not be solved by LP relaxation For remained instances of unsolvable ones, we subtract columns from the finale simplex table to get another integer solution in an iterative manner. Computational results having up to 10,000 0-1 variables show better performance of the column subtraction method solving the remained instances of SSP than complex branch and-bound algorithm by LINDO.

ON A SELF-SIMILAR MEASURE ON A SELF-SIMILAR CANTOR SET

  • Baek, In-Soo
    • 충청수학회지
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    • 제16권2호
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    • pp.1-10
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    • 2003
  • We compare a self-similar measure on a self-similar Cantor set with a quasi-self-similar measure on a deranged Cantor set. Further we study some properties of a self-similar measure on a self-similar Cantor set.

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DERIVATIVE OF THE RIESZ-NÁGY-TAKÁCS FUNCTION

  • Baek, In-Soo
    • 대한수학회보
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    • 제48권2호
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    • pp.261-275
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    • 2011
  • We give characterizations of the differentiability points and the non-differentiability points of the Riesz-N$\'{a}$gy-Tak$\'{a}$cs(RNT) singulr function using the distribution sets in the unit interval. Using characterizations, we show that the Hausdorff dimension of the non-differentiability points of the RNT singular function is greater than 0 and the packing dimension of the infinite derivative points of the RNT singular function is less than 1. Further the RNT singular function is nowhere differentiable in the sense of topological magnitude, which leads to that the packing dimension of the non-differentiability points of the RNT singular function is 1. Finally we show that our characterizations generalize a recent result from the ($\tau$, $\tau$ - 1)-expansion associated with the RNT singular function adding a new result for a sufficient condition for the non-differentiability points.

MULTIFRACTAL ANALYSIS OF A GENERAL CODING SPACE

  • Baek, In Soo
    • 충청수학회지
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    • 제19권4호
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    • pp.357-364
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    • 2006
  • We study Hausdorff and packing dimensions of subsets of a general coding space with a generalized ultra metric from a multifractal spectrum induced by a self-similar measure on a self-similar Cantor set using a function satisfying a H${\ddot{o}}$older condition.

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사출성형에서의 Penalty Formulation을 이용한 Packing 과정 해석 (Analysis of Packing Procedure Using Penalty Formulation in Injection Molding)

  • 강성용;김승모;김선경;이우일;김대환;김우규;김형채
    • 대한기계학회:학술대회논문집
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    • 대한기계학회 2004년도 추계학술대회
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    • pp.916-921
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    • 2004
  • The penalty method has been widely applied to analyses of incompressible fluid flow. However, we have not yet found any prior studies that employed penalty method to analyze compressible fluid flow. In this study, with an eye on the apparent similarity between the slight compressible formulation and the penalty formulation, we have proposed a new approximate approach that can analyze compressible packing process using the penalty parameter l. Based on the assumption of the isothermal flow, a set of reference solutions was obtained to verify the validity of the proposed scheme. Furthermore, we have applied the proposed scheme to the analysis of the packing process of different cases.

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ON SIMULTANEOUS LOCAL DIMENSION FUNCTIONS OF SUBSETS OF ℝd

  • OLSEN, LARS
    • 대한수학회보
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    • 제52권5호
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    • pp.1489-1493
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    • 2015
  • For a subset $E{\subseteq}\mathbb{R}^d$ and $x{\in}\mathbb{R}^d$, the local Hausdorff dimension function of E at x and the local packing dimension function of E at x are defined by $$dim_{H,loc}(x,E)=\lim_{r{\searrow}0}dim_H(E{\cap}B(x,r))$$, $$dim_{P,loc}(x,E)=\lim_{r{\searrow}0}dim_P(E{\cap}B(x,r))$$, where $dim_H$ and $dim_P$ denote the Hausdorff dimension and the packing dimension, respectively. In this note we give a short and simple proof showing that for any pair of continuous functions $f,g:\mathbb{R}^d{\rightarrow}[0,d]$ with $f{\leq}g$, it is possible to choose a set E that simultaneously has f as its local Hausdorff dimension function and g as its local packing dimension function.

정밀 사출성형에서의 Penalty Formulation을 이용한 Packing 과정 해석 (Analysis of Packing Procedure Using Penalty Formulation in Precision Injection Molding)

  • 김선경;김승모;최두선;이우일;강성용
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 추계학술대회 논문집
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    • pp.105-110
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    • 2005
  • The penalty method has been widely applied to analyses of incompressible fluid flow. However, we have not yet found any prior studies that employed penalty method to analyze compressible fluid flow. In this study, with an eye on the apparent similarity between the slight compressible formulation and the penalty formulation, we have proposed a modified approximate approach that can analyze compressible packing process using the penalty parameter, which is an improvement on an earlier formulation (KSME, 2004B). Based on the assumption of the isothermal flow, a set of reference solutions was obtained to verify the validity of the proposed scheme. Furthermore, we have applied the proposed scheme to the analysis of the packing process of different cases.

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ON THREE CONDITIONS ON A PERTURBED CANTOR SET

  • BAEK, IN-SOO
    • 호남수학학술지
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    • 제28권3호
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    • pp.387-393
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    • 2006
  • We study three conditions which seem similar but a little different on a perturbed Cantor set. Since they give different conditions on a perturbed Cantor set, we have another results corresponding to the conditions. We compare the conditions and give different examples which provide different results.

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ON CANTOR SETS AND PACKING MEASURES

  • WEI, CHUN;WEN, SHENG-YOU
    • 대한수학회보
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    • 제52권5호
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    • pp.1737-1751
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    • 2015
  • For every doubling gauge g, we prove that there is a Cantor set of positive finite $H^g$-measure, $P^g$-measure, and $P^g_0$-premeasure. Also, we show that every compact metric space of infinite $P^g_0$-premeasure has a compact countable subset of infinite $P^g_0$-premeasure. In addition, we obtain a class of uniform Cantor sets and prove that, for every set E in this class, there exists a countable set F, with $\bar{F}=E{\cup}F$, and a doubling gauge g such that $E{\cup}F$ has different positive finite $P^g$-measure and $P^g_0$-premeasure.