• Polymer(Korea)
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• v.25 no.4
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• pp.536-544
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• 2001

We investigate, in the viewpoint of mathematical stability, the validity of the time-strain separability hypothesis employed in polymer viscoelasticity on the basis of experimental results. There have been suggested two distinct stability criteria such as Hadamard related to quick response and dissipative stability conditions, and in the limit of high deformation rate we have proved that separable constitutive equations are either Hadamard or dissipative unstable. The fact that the separability is not valid in the short time region in stress relaxation experiments exactly coincides with the results of our analysis. Therefore, since the application of the separability hypothesis incurs thermodynamic inconsistency as well as mathematical instability, such application should be avoided in the formulation of constitutive equations. In addition, careful attention should be paid to the limit of its validity even in experiments. It is also proved that there is neither theoretical nor physical validity of using the damping function.

• Korean Journal of Mathematics
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• v.29 no.3
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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.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
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• 2004.04a
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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.

• Korean Journal of Remote Sensing
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• v.36 no.1
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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%.

• The Journal of the Korea Contents Association
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• v.7 no.1
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• pp.215-224
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• 2007

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. This Study concludes, each image was measured by the rate of class separability, values classified were showed highly about $1,600{\sim}2,000$.

• Korea-Australia Rheology Journal
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• v.14 no.1
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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.

• Proceedings of the Korean Society of Rheology Conference
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• 2000.05a
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• pp.55-57
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• 2000

• Journal of Arbitration Studies
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• v.24 no.2
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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.

• Journal of Arbitration Studies
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• v.13 no.2
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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.

• Proceedings of the IEEK Conference
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• 1998.06a
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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.