• 제목/요약/키워드: theory of constraints

검색결과 479건 처리시간 0.042초

A Study of English Loanwords

  • Lee, Hae-Bong
    • 대한음성학회:학술대회논문집
    • /
    • 대한음성학회 2000년도 7월 학술대회지
    • /
    • pp.365-365
    • /
    • 2000
  • English segments adopted into Korean can be divided into three types: Some English segments /$m, {\;}n, {\;}{\eta}, {\;}p^h, {\;}t^h, {\;}k^h$/ are adopted into the original sound [$m, {\;}n, {\;}{\eta}, {\;}p^h, {\;}t^h, {\;}k^h$] in Korean. Other segments /b, d, g/ appear in the voiceless stop form [p, t, k]. Generative Phonology explains the presence of the above English segments in Korean but it cannot explain why the English segments /$f, {\;}v, {\;}{\Theta}, {\;}{\breve{z}}, {\;}{\breve{c}}, {\;}{\breve{j}}$/ disappear during the adopting process. I present a set of universal constraints from the Optimality Theory proposed by Prince and Smolensky(l993) and I show how English segments differently adopted into Korean can be explained by these universal constraints such as Faith(feature). N oAffricateStop, Faith(nasal), NoNasalStop, Faith(voice), NoVoicedStop and the interaction of these constraints. I conclude that this Optimality Theory provides insights that better capture the nature of the phonological phenomena of English segments in Korean.

  • PDF

An Optimality Approach to NPI Constructions

  • Moon, Seung-Chul;Sohng, Hong-Ki
    • 영어영문학
    • /
    • 제55권3호
    • /
    • pp.459-474
    • /
    • 2009
  • The Journal of English Language and Literature. The purpose of this study is to provide an optimality theoretic approach to NPIs (Negative Polarity Items) in English and Korean by proposing three universal constraints. The constraints are C-command Condition (CCC): NPI must be c-commanded by a constituent with negative meaning; Locality Condition (LOC): NPI must be bound in the local domain; Subjacency: NPI licensing must satisfy Subjacency Condition (SBJ); Previous analyses have shown that these three constraints control NPIs in one way or another. This study attempts to demonstrate that NPIs in both English and Korean languages can be nicely accounted for by setting a different constraint hierarchy for the two independent languages. That is, by slightly changing the constraint hierarchy, distributional differences of NPIs in both languages can be accounted straightforwardly within the framework of Optimality Theory.

제약이론과 시뮬레이션을 이용한 진단 의료 혈액분석기의 생산성 향상 방안 연구 (Study on the Productivity Improvement of Diagnostic Medical Blood Analyzers using Theory of Constraints and Simulation)

  • 맹주혁;이강원
    • 한국시뮬레이션학회논문지
    • /
    • 제22권2호
    • /
    • pp.21-31
    • /
    • 2013
  • 진단 의료 혈액 분석기는 세계 의료기기 시장에서 지속적인 고성장세를 이어가고 있다. 본 연구에서는 국내 혈액분석기가 진단 의료기기 시장에서 가격경쟁력을 높여갈 수 있도록 비용을 절감시키면서 낮은 생산원가를 실현시킬 수 있는 생산성 향상 방안을 마련하는데 중점을 두었다. TOC 제약이론의 집중개선 5단계와 공장자동화 전략을 기반으로 시뮬레이션을 모델링하였으며 단계별로 대안을 제시하고 결과를 예측하여 분석하였다. ARENA 시뮬레이션을 이용하여 현장의 상황을 정확히 모델링하였으며 TOC 제약이론 집중개선 5단계를 도입하여 보다 체계적이고 효과적으로 개선하였다. 제약공정의 능력을 확장하는 단계에서는 적절한 공장자동화를 통하여 생산성을 크게 향상시켰으며 자동화 설비 도입에 따른 경제성 분석을 실시하여 투자대비 효과를 입증하였다.

NECESSARY CONDITIONS FOR OPTIMAL CONTROL PROBLEM UNDER STATE CONSTRAINTS

  • KIM KYUNG-EUNG
    • 대한수학회지
    • /
    • 제42권1호
    • /
    • pp.17-35
    • /
    • 2005
  • Necessary conditions for a deterministic optimal control problem which involves states constraints are derived in the form of a maximum principle. The conditions are similar to those of F.H. Clarke, R.B. Vinter and G. Pappas who assume that the problem's data are Lipschitz. On the other hand, our data are not continuously differentiable but only differentiable. Fermat's rule and Rockafellar's duality theory of convex analysis are the basic techniques in this paper.

Size dependent vibration of embedded functionally graded nanoplate in hygrothermal environment by Rayleigh-Ritz method

  • Singh, Piyush P.;Azam, Mohammad S.
    • Advances in nano research
    • /
    • 제10권1호
    • /
    • pp.25-42
    • /
    • 2021
  • In this article, the vibration behavior of embedded Functionally Graded Nanoplate (FGNP) employing nonlocal Kirchhoff's plate theory has been investigated under hygrothermal environment. The FGNP is considered to be supported by Winkler-Pasternak foundation. The Eringen's differential theory is used for size effect on the vibration of the FGNP. Rayleigh-Ritz method with orthogonal polynomials are employed for the governing equations and edge constraints. The advantage of this method is that it overcomes all the drawbacks of edge constraints and can easily handle any combinations of mixed edge constraints. The coefficients viz. moisture expansion, thermal expansion and elastic coefficients are considered to be transversely graded across the FGNP. The similarity of the calculated natural frequencies is examined with the previous research, and a good concurrency is seen. The objective of this article is to analyze the parameters' effect on the nondimensionalized frequency of embedded FGNP under hygrothermal environment subjected to all possible edge constraints. For this, uniform and linear rise of temperature and moisture concentration are considered. The study highlights that the nonlocal effect is pronounced for higher modes. Moreover, the effect of the Pasternak modulus is seen to be prominent compared to the Winkler modulus on non dimensionalized frequencies of FGNP.

역나선 이론을 이용한 저자유도 병렬형 기구의 강성해석 (Stiffness Analysis of a Low-DOE Parallel Manipulator using the Theory of Reciprocal Screws)

  • 김한성
    • 대한기계학회논문집A
    • /
    • 제29권5호
    • /
    • pp.680-688
    • /
    • 2005
  • This paper presents a methodology for the stiffness analysis of a low-DOF parallel manipulator. A low-DOF parallel manipulator is a spatial parallel manipulator which has less than six degrees of freedom. The reciprocal screws of actuations and constraints in each leg can be determined by making use of the theory of reciprocal screws, which provide information about reaction forces due to actuations and constraints. When pure farce is applied to a leg, the leg stiffness is modeled as a linear spring along the line. For pure couple, it is modeled as a rotational spring about the axis. It is shown that the stiffness model of an it_DOF parallel nipulator consists of F springs related to actuations and 6-F springs related to constraints connected from the moving platform to the base in parallel. The 6x f Cartesian stiffness matrix is derived, which is the sum of the Cartesian stiffness matrices of actuations and constraints. Finally, the 3-UPU, 3-PRRR, and Tricept parallel manipulators are used as examples to demonstrate the methodology.

역나선 이론을 이용한 저자유도 평행구조 기구의 강성해석 (Stiffness Analysis of a Low-DOF Parallel Manipulator using the Theory of Reciprocal Screws)

  • 김한성
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2004년도 추계학술대회
    • /
    • pp.573-578
    • /
    • 2004
  • This paper presents a methodology for the stiffness analysis of a low-DOF parallel manipulator. A low-DOF parallel manipulator is a spatial parallel manipulator which has less than six degrees of freedom. The reciprocal screws of actuations and constraints in each leg can be determined by making use of the theory of reciprocal screws, which provide information about reaction forces due to actuations and constraints. When pure force is applied to a leg, the leg stiffness is modeled as a linear spring along the line. For pure couple, it is modeled as a rotational spring about the axis. It is shown that the stiffness model of an F-DOF parallel manipulator consists of F springs related to actuations and 6-F springs related to constraints connected from the moving platform to the base in parallel. The $6{\times}6$ Cartesian stiffness matrix is obtained, which is the sum of the Cartesian stiffness matrices of actuations and constraints. Finally, a 3-UPU parallel manipulator is used as an example to demonstrate the methodology.

  • PDF

DECISION SUPPORT SYSTEM FOR SUBURBAN STATION REHABILITATION

  • TaeHoon Hong;Sangyoub Lee
    • 국제학술발표논문집
    • /
    • The 1th International Conference on Construction Engineering and Project Management
    • /
    • pp.855-861
    • /
    • 2005
  • Every public agency governing infrastructure has to plan effectively for rehabilitation of existing facilities within the constraints of the capital program. Numerous technical, social, political, financial, and management constraints govern the decision to rehabilitate a facility. However, without a systematic procedure for selecting facilities for rehabilitation, within the prevailing constraints, it is possible that the funds available for rehabilitation might be suboptimized. Therefore, a decision support system that assists the user in selecting facilities for rehabilitation while considering the technical, social, financial, and political and management constraints will be useful in the decision-making process. This paper compares the Analytical Hierarchy Process (AHP) with the Swing Weight method used to prioritize functional criteria for suburban station rehabilitation. This paper also contains a brief discussion about the relevance of the Multi Attribute utility theory in developing a decision model for the problem at hand. The results of this paper provides the user with a decision support system that would prioritize the stations in order of their weights obtained by a systematic evaluation of various criteria and sub-criteria involved in the decision making process

  • PDF

변형 이론을 기반으로한 곡면의 최적 근사 전개 (Optimal Approximated Development of General Curved Plates Based on Deformation Theory)

  • 유철호;신종계
    • 한국CDE학회논문집
    • /
    • 제7권3호
    • /
    • pp.190-201
    • /
    • 2002
  • Surfaces of many engineering structures, specially, those of ships and airplanes are commonly fabricated as doubly curved shapes as well as singly curved surfaces to fulfill functional requirements. Given a three dimensional design surface, the first step in the fabrication process is unfolding or planar development of this surfaces into a planar shape so that the manufacturer can determine the initial shape of the flat plate. Also a good planar development enables the manufacturer to estimate the strain distribution required to form the design shape. In this paper, an algorithm for optimal approximated development of a general curved surface, including both singly and doubly curved surface is developed in the sense that the strain energy from its planar development to the design surface is minimized, subjected to some constraints. The development process is formulated into a constrained nonlinear programming problem, which is on basis of deformation theory and finite element. Constraints are subjected to characteristics of the fabrication method. Some examples on typical surfaces and the practical ship surfaces show the effectiveness of this algorithm.