• 제목/요약/키워드: separability

검색결과 154건 처리시간 0.021초

고분자 점탄성에서 Time-Strain Non-Separability와 그 열역학적 의미 (Time-Strain Non-Separability in Polymer Viscoelasticity and Its Thermodynamic Consequence)

  • 권영돈
    • 폴리머
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    • 제25권4호
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    • pp.536-544
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    • 2001
  • 실험적 사실에 근거하여 고분자 유체의 점탄성 구성방정식에 빈번히 적용되어온 time-strain separability 가설의 타당성을 수학적 안정성 관점에서 분석한다. 안정성 조건으로는 방정식의 빠른 응답과 관련된 Hadamard 안정성과 소산 성질에 의하여 결정되는 소산 안정성이 있으며, asymptotic 분석을 이용한 결과 가설을 따르는 구성방정식은 Hadamard 또는 소산 불안정함이 증명되었다. 응력완화 실험에서 이미 관찰된 짧은 시간영역에서 time-strain separability의 가설이 적용되지 않는다는 사실은 본 결과와 일치한다. 따라서 separability를 구성방정식에 적용하는 것은 수학적 불안정뿐 아니라 열역학적 모순점을 나타내게 되며, 또한 실험에서도 그 타당성의 한계에 주의할 필요가 있다. 더욱이 damping 함수 역시 실제와는 무관한 가상적 값을 제공하므로 damping 함수의 사용은 긴 시간영역에서 응력완화 거동을 기술하기 위한 curve fitting 이상의 의미는 없다 하겠다.

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RESIDUAL FINITENESS AND ABELIAN SUBGROUP SEPARABILITY OF SOME HIGH DIMENSIONAL GRAPH MANIFOLDS

  • Kim, Raeyong
    • Korean Journal of Mathematics
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    • 제29권3호
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    • pp.603-612
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    • 2021
  • We generalize 3-manifolds supporting non-positively curved metric to construct manifolds which have the following properties : (1) They are not locally CAT(0). (2) Their fundamental groups are residually finite. (3) They have subgroup separability for some abelian subgroups.

위성영상 종류에 따른 분리도 특성 (Class Separability according to the different Type of Satellite Images)

  • 손경숙;최현;김시년;강인준
    • 한국측량학회:학술대회논문집
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    • 한국측량학회 2004년도 춘계학술발표회논문집
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    • pp.245-250
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    • 2004
  • The classification of the satellite images is basic part in Remote sensing. In classification of the satellite images, class separability feature is very effective accuracy of the images classified. For improving classification accuracy, It is necessary to study classification methode than analysis of class separability feature deciding classification probability. In this study, IKONOS, SPOT 5, Landsat TM, were resampled to sizes 1m grid. Above images were calculated the class separability prior to the step for classification of pixels. The results of the study were valued necessary process in geometric information building. This study help to improve accuracy of classification as feature of class separability in the class through optimizing previous classification steps.

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Evaluating the Contribution of Spectral Features to Image Classification Using Class Separability

  • Ye, Chul-Soo
    • 대한원격탐사학회지
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    • 제36권1호
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    • pp.55-65
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    • 2020
  • Image classification needs the spectral similarity comparison between spectral features of each pixel and the representative spectral features of each class. The spectral similarity is obtained by computing the spectral feature vector distance between the pixel and the class. Each spectral feature contributes differently in the image classification depending on the class separability of the spectral feature, which is computed using a suitable vector distance measure such as the Bhattacharyya distance. We propose a method to determine the weight value of each spectral feature in the computation of feature vector distance for the similarity measurement. The weight value is determined by the ratio between each feature separability value to the total separability values of all the spectral features. We created ten spectral features consisting of seven bands of Landsat-8 OLI image and three indices, NDVI, NDWI and NDBI. For three experimental test sites, we obtained the overall accuracies between 95.0% and 97.5% and the kappa coefficients between 90.43% and 94.47%.

위성영상의 종류에 따른 분리도 특성의 상관관계 분석 (Analysis of Relation of Class Separability According to Different Kind of Satellite Images)

  • 홍순헌
    • 한국콘텐츠학회논문지
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    • 제7권1호
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    • pp.215-224
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    • 2007
  • 위성영상의 분류는 원격탐사의 가장 기본적인 분야이다. 위성영상분리도 위성영상의 분류에 있어 영상 정확도 향상에 매우 효율적이라 할 수 있다. 영상분류를 향상시키기 위해서 분리도의 특성을 파악하여 분류의 정확도와의 상관관계를 분석하였다. 영상은 영상마다의 분리도를 비교, 분석하기 위해 IKONOS 영상, SPOT 5 영상, Landsat IM 영상을 1m의 해상도로 리샘플링하였다. 본 연구에서 위성영상별로 클래스 분리도를 측정한 결과 분리도 값이 대체로 $1,600{\sim}2,000$으로 높게 나타났다.

Recent results on the analysis of viscoelastic constitutive equations

  • Kwon, Youngdon
    • Korea-Australia Rheology Journal
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    • 제14권1호
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    • pp.33-45
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    • 2002
  • Recent results obtained for the port-pom model and the constitutive equations with time-strain separability are examined. The time-strain separability in viscoelastic systems Is not a rule derived from fundamental principles but merely a hypothesis based on experimental phenomena, stress relaxation at long times. The violation of separability in the short-time response just after a step strain is also well understood (Archer, 1999). In constitutive modeling, time-strain separability has been extensively employed because of its theoretical simplicity and practical convenience. Here we present a simple analysis that verifies this hypothesis inevitably incurs mathematical inconsistency in the viewpoint of stability. Employing an asymptotic analysis, we show that both differential and integral constitutive equations based on time-strain separability are either Hadamard-type unstable or dissipative unstable. The conclusion drawn in this study is shown to be applicable to the Doi-Edwards model (with independent alignment approximation). Hence, the Hadamardtype instability of the Doi-Edwards model results from the time-strain separability in its formulation, and its remedy may lie in the transition mechanism from Rouse to reptational relaxation supposed by Doi and Edwards. Recently in order to describe the complex rheological behavior of polymer melts with long side branches like low density polyethylene, new constitutive equations called the port-pom equations have been derived in the integral/differential form and also in the simplifled differential type by McLeish and carson on the basis of the reptation dynamics with simplifled branch structure taken into account. In this study mathematical stability analysis under short and high frequency wave disturbances has been performed for these constitutive equations. It is proved that the differential model is globally Hadamard stable, and the integral model seems stable, as long as the orientation tensor remains positive definite or the smooth strain history in the flow is previously given. However cautious attention has to be paid when one employs the simplified version of the constitutive equations without arm withdrawal, since neglecting the arm withdrawal immediately yields Hadamard instability. In the flow regime of creep shear flow where the applied constant shear stress exceeds the maximum achievable value in the steady flow curves, the constitutive equations exhibit severe instability that the solution possesses strong discontinuity at the moment of change of chain dynamics mechanisms.

미국 판례상 중재조항의 분리가능성에 관한 고찰 (A Study on the Separability of an Arbitration Clause in United States Cases)

  • 강수미
    • 한국중재학회지:중재연구
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    • 제24권2호
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    • pp.109-136
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    • 2014
  • The separability of an arbitration clause is generally recognized throughout the world, but there are no provisions of it under the Federal Arbitration Act(FAA) of the United States. As such, the controversy over the recognition of separability has developed with the rise of certain cases. The Supreme Court recognized this separability based on section 4 of the FAA in the decision of the Prima Paint case. The Court ruled that courts must decide the claim about the fraudulent inducement of an arbitration agreement itself, but they must not decide the claim about the fraudulent inducement of a contract involving a broad arbitration clause, and they have to proceed with the arbitration. The Court said that the subject of an arbitral award is set by the agreement of the parties, and thereby arbitrators can decide the issues about the fraudulent inducement of a contract on the basis of the arbitration clause when it is broad to the point of including the issues. Many courts have extended the separability beyond the fraud context to include other defenses to contract formation in the federal courts such as the occurrence of mistake, illegality, and frustration of purpose. In interpreting the parties' intention of ensuring arbitrator competence, the Supreme Court has treated differently the issues about whether the arbitration agreement exists or not and the issues about whether the preconditions for dispute resolution by a valid arbitration agreement is fulfilled or not. The Court holds that the federal policy in favor of arbitration does not apply to the former issues, and arbitrators can decide theses issues only when parties assign them clearly and unmistakably to them. However, the later issues receive a presumption in favor of arbitration; i.e., when the interpretation of a valid arbitration clause is contested, the arbitrators can decide these issues. In the First Options case, the former issue was questioned. The question of the separability of an arbitration clause is where the validity of the main contract involving the arbitration clause is contested. Therefore, the doctrine of separability did not operate in the First Options case in which the validity of the arbitration clause itself was questioned, and the decision in the First Options was irrelevant to the separability. I think that the Prima Paint case and the First Options case have different issues, and there is no tension between them.

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국제상사중재에 있어서의 분리원칙과 중재인의 자기관할권판정의 원칙 (The Doctrine of Separability and Kompetenz-Kompetenz under International Commercial Arbitration.)

  • 박영길
    • 한국중재학회지:중재연구
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    • 제13권2호
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    • pp.211-234
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    • 2004
  • When there is a dispute in international commercial contracts, the arbitration system, which is an ADR system, is often utilized. The Arbitration system can only be put to use when there is an arbitration agreement between the parties concerned, but even in this case, the one party of the contract tries to avoid the braking of the arbitration. In this case, separability doctrine and Kompetenz-Kompetenz doctrine can be used for the smooth operation of the Arbitration system. This paper reviews these two doctrines, taking a close look at UNCITRAL, ICC, America's FAA and case examples, and France's system and its case examples. U.S. has adopted separability doctrine for the Prima paint case but not the Kompetenz-Kompetenz doctrine. English has adopted separability doctrine for the Heyman case but not the Kompetenz-Kompetenz doctrine. However in France, both doctrines are adopted. France, which accords international arbitration the most highly favorable status of the three nations, has developed the legal framework that best promotes the public policy goal of encouraging the use of arbitration agreements in international commerce. In Korea, the above doctrines are prescribed in Article 17 of the arbitration law, as prescribed by the UNCITRAL Model law. However it takes the form of German laws. The adoption of the French system would have been wiser considering the promotion of the arbitration system.

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원전 적용을 위한 최적 센서 위치를 가진 고장진단 시스템의 개발 (The Development of Fault Diagnosis System for Nuclear Power Plants with Optimal Sensor Location)

  • 김용민;홍호택박재홍
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 하계종합학술대회논문집
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    • pp.211-214
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    • 1998
  • A detection filter assigns a specific direction to the response with respect to each fault, by which it can detect the occurrence of the several faults. The separability of a detection filter can be determined by the orthogonality among these directions. In this paper, we define the separability of a detection filter as the orthogonality of the directions in output space, and present it mathematically by using conditions number. An algorithm to determine the optimal sensor gain to maximize separability is proposed and applied to the PWR nuclear reactor model.

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