• 제목/요약/키워드: Structured problems

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비단순문제 해결을 위한 GIS 향상방안 (Conceptualization-oriented Spatial Decision Support System for III-structured Problems)

  • 김은형
    • Spatial Information Research
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    • 제1권1호
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    • pp.63-72
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    • 1993
  • 현재의 GIS가 감당할 수 있는 것은 모든 공간적 문제는 아니다. 그동안 알려진 GIS는 정보를 생산해 내는 정보위주의 GIS일뿐 정보의 다각적 이해와 의사결정과 정에 깊이 관여하지 못하였다. 단순문제(structured problems)들을 해결하기에는 정보위주의 GIS가 적합하지만 계획과 설계와 같은 비단순문제(ill-structured problems)들을 다루기에는 미흡한 단계이며, 이 단계에서 도약하기 위해 개념위주의 SDSS(Spatual Decision Suppert System)로 발전되어야 한다. 이 글에서는 개념위주의 SDSS가 비단순문제 해결을 지원하기 위한 기구로서 소개되며 정보위주 GIS의 미래상으로 비젼(vision)을 제시한다.

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Fast Training of Structured SVM Using Fixed-Threshold Sequential Minimal Optimization

  • Lee, Chang-Ki;Jang, Myung-Gil
    • ETRI Journal
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    • 제31권2호
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    • pp.121-128
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    • 2009
  • In this paper, we describe a fixed-threshold sequential minimal optimization (FSMO) for structured SVM problems. FSMO is conceptually simple, easy to implement, and faster than the standard support vector machine (SVM) training algorithms for structured SVM problems. Because FSMO uses the fact that the formulation of structured SVM has no bias (that is, the threshold b is fixed at zero), FSMO breaks down the quadratic programming (QP) problems of structured SVM into a series of smallest QP problems, each involving only one variable. By involving only one variable, FSMO is advantageous in that each QP sub-problem does not need subset selection. For the various test sets, FSMO is as accurate as an existing structured SVM implementation (SVM-Struct) but is much faster on large data sets. The training time of FSMO empirically scales between O(n) and O($n^{1.2}$), while SVM-Struct scales between O($n^{1.5}$) and O($n^{1.8}$).

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구조화 정도가 다른 수학적 동형 문제 사이의 유추적 전이 분석 (Analysis on Analogical Transfer between Mathematical Isomorphic Problems with Different Level of Structuredness)

  • 성창근;박성선
    • 한국수학교육학회지시리즈C:초등수학교육
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    • 제15권2호
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    • pp.59-75
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    • 2012
  • 본 연구의 목적은 구조화 정도가 다른 수학적 동형 문제 사이의 유추적 전이를 분석하는 것이다. 이를 위해 다음과 같은 연구문제를 설정하여 분석하였다. 첫째, 구조화 정도가 다른 수학 문제를 해결하는데 사용된 전략의 변화 양상은 어떠한가? 둘째, 구조화된 문제와 비-구조화된 문제를 해결하는데 비례식 알고리듬 전략을 사용한 학생과 그렇지 않은 학생의 문제해결 특징은 어떠한가? 연구 결과를 다음과 같다, 첫째, 구조화 정도가 낮은 문제의 해결에서는 곱셈적 전략의 사용빈도가 증가하였으며, 반대로 비례식 알고리듬 전략 사용빈도는 감소하였다. 둘째, 비와 비례에 대해 개념적 이해 수준이 높은 학생은 구조화정도가 다른 문제들 사이의 구조적 유사성을 인식하고, 비례식 알고리듬 전략을 사용해 문제를 성공적으로 해결하였다. 이 연구는 학생들의 유추적 전이 능력을 신장시키기 위해 수학 수업은 어떠한 점에 초점을 맞추어야 하는지와 그리고 유추적 전이 연구에 대한 새로운 방법론적 대안을 제시했다는 점에서 그 의의를 찾을 수 있다.

A Nonlinear Programming Approach to Biaffine Matrix Inequality Problems in Multiobjective and Structured Controls

  • Lee, Joon-Hwa;Lee, Kwan-Ho;Kwon, Wook-Hyun
    • International Journal of Control, Automation, and Systems
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    • 제1권3호
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    • pp.271-281
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    • 2003
  • In this paper, a new nonlinear programming approach is suggested to solve biaffine matrix inequality (BMI) problems in multiobjective and structured controls. It is shown that these BMI problems are reduced to nonlinear minimization problems. An algorithm that is easily implemented with existing convex optimization codes is presented for the nonlinear minimization problem. The efficiency of the proposed algorithm is illustrated by numerical examples.

과학고 학생들의 비구조화된 문제 해결 과정 특성 분석 (Science High School Students' Analysis of Characteristics on Ill-Structured Problem-Solving Process)

  • 서진수;한신;김형범;정진우
    • 대한지구과학교육학회지
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    • 제5권1호
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    • pp.8-19
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    • 2012
  • The purpose of this study is to: analyze the characteristics on ill-structured problem-solving process; examine the type of memories used in their monitoring. The data were primary collected from observation and secondary the semi-structured in-depth interviews based on analysis of observation results with two students who belong to science school and a guidance. The findings of this study revealed that the ill-structured problems possess multiple representations and the upper level's problem have several sub-problems. And multiple steps simultaneously exist in particular stage of problem-solving process that is not single sequential but complex flow and have high frequency of discussion step. Type of memories used in ill-structured problems include idiosyncratic memories which is related in personal histories such as school performance, problem-related memories, abstract rules and intuition.

A HYBRID METHOD FOR REGULARIZED STRUCTURED LINEAR TOTAL LEAST NORM

  • KWON SUNJOO
    • Journal of applied mathematics & informatics
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    • 제18권1_2호
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    • pp.621-637
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    • 2005
  • A hybrid method solving regularized structured linear total least norm (RSTLN) problems, which have highly ill-conditioned coefficient matrix with special structures, is suggested and analyzed. This scheme combining RSTLN algorithm and separation by parts guarantees the convergence of parameters and has an advantages in reducing the residual norm and relative error of solutions. Computational tests for problems arisen in signal processing and image formation process confirm that the presenting method is effective for more accurate solutions to (R)STLN problem than the (R)STLN algorithm.

학문적 협력을 돕기 위한 구조적 전자저널 (Structured Electronic Journal for Scientific Collaboration)

  • Yongmoo Suh
    • 정보기술과데이타베이스저널
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    • 제3권2호
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    • pp.53-73
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    • 1996
  • Thesedays more collaboration is required of scholars than before, because some complex problems are beyond the individuals' research capability. Traditional print-based journal systems have been playing a role of supporting scientific collaboration, in that they provide the state-of-the-art knowledge. Those journal systems, however, are known to have some problems. To cope with some of those problems of the print-based journal systems, electronic journal systems have been suggested and implemented. Investigation shows us that electronic journal systems still have some problems. This paper proposes a new form of electronic journal system, structured electronic journal system, which is believed to better support the scientific collaboration. It is designed so that it is easier to figure out the synopsis of an article and so that authors and referees of a submitted paper can participate in the discussion for verifying the significance of the paper. Object-oriented design of a structured electronic journal system which is to be built on top of a object-oriented database system is explained with example structures.

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Reconstruction of structured models using incomplete measured data

  • Yu, Yan;Dong, Bo;Yu, Bo
    • Structural Engineering and Mechanics
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    • 제62권3호
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    • pp.303-310
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    • 2017
  • The model updating problems, which are to find the optimal approximation to the discrete quadratic model obtained by the finite element method, are critically important to the vibration analysis. In this paper, the structured model updating problem is considered, where the coefficient matrices are required to be symmetric and positive semidefinite, represent the interconnectivity of elements in the physical configuration and minimize the dynamics equations, and furthermore, due to the physical feasibility, the physical parameters should be positive. To the best of our knowledge, the model updating problem involving all these constraints has not been proposed in the existed literature. In this paper, based on the semidefinite programming technique, we design a general-purpose numerical algorithm for solving the structured model updating problems with incomplete measured data and present some numerical results to demonstrate the effectiveness of our method.

WEB-BASED SIMULATION MODEL FOR MULTI-ATTRIBUTE STRUCTURED DECISION SUPPORT SYSTEM

  • Hwang, Heung-Suk;Cho, Gyu-Sung
    • 한국시뮬레이션학회:학술대회논문집
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    • 한국시뮬레이션학회 2001년도 The Seoul International Simulation Conference
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    • pp.44-49
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    • 2001
  • This paper is concerned with development of a multi-attribute structured decision model. In this study, we used AHP(analytic hierarchy process) and fuzzy set ranking methodology to overcome the multi-attributes structured decision problems ; such as multi-objective, multi-criterion, and multi-attributes. We proposed a 2-step approach : 1) individual evaluation and 2) integration of individual evaluations. In the first step, we define the performance factors and construct ana]isis structure, and in the second step performance evaluation by individual evaluators, and in second step, the results of individual evaluations are integrate. Also we developed a systematic and practical computer program to solve the problems according to the proposed methods. The proposed approach was known to be effective through a set of sample problems.

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Compression and shear responses of structured clays during subyielding

  • Suebsuk, Jirayut;Horpibulsuk, Suksun;Liu, Martin D.
    • Geomechanics and Engineering
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    • 제18권2호
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    • pp.121-131
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    • 2019
  • This article discusses the phenomenon of plastic volumetric deformation of naturally structured clays before virgin yielding, i.e., subyielding behavior. A simple approach representing both the compression and shear responses of the clays during subyielding is demonstrated. A new compression model for structured clays based on the theoretical framework of the Structured Cam Clay (SCC) model via incorporation of the subyielding behavior is presented. Two stress surfaces are introduced to distinguish the subyielding and virgin yielding. The hardening and destructuring processes of structured clays under isotropic compression and shear are the focus of this work. The simulations of the compression and shear of eleven natural clays are studied for validation. The proposed work can accurately predict the subyielding behavior of structured clays both qualitatively and quantitatively and can be used for modeling structured clays under compression and shear responses in geological and geotechnical engineering problems.