• 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.

• 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.

• Journal of Distribution Science
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• v.15 no.2
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• pp.59-68
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• 2017

Purpose - The year 2016 marks 20 years since the opening of Korean distribution market in 1996. After this opening, the domestic market expanded and modernized, and has grown to become an advanced distribution market with a greater range of consumer choices. On the other hand, traditional markets have waned and their management has become worse. However, traditional markets do not have economic value alone. This study examines the effects of social value in traditional market such as the value of Cultural Tourism and the value of Sharing Community with Traditional Market on Satisfaction, Loyalty and Place Attachment of the residents. Research design, data and methodology - A questionnaire was organized for this study after a hypothesis was set based on theoretical background. Verification of the hypothesis was undertaken by statistically analyzing questionnaire responses. Personal interviews were performed for this study, and a total of 300 responses were collected, of which 228 responses (76%) were from women. The survey coverage was divided into 10 regions ranging from metropolitan areas to the provincial level, and the age groups were divided into 30s to 60s to ensure diversity of the area and age. Results - To summarize the study results, through verification of the hypothesis in terms of meaningful influence, it appears the values of Cultural Tourism to Satisfaction and Loyalty are supported. On the other hand, the value of Sharing Community is only supported for Satisfaction. It appears that Satisfaction to Loyalty and Loyalty to Place Attachment are meaningful effects. The mediator effect was also reconciled through satisfaction and loyalty. Loyalty was analyzed in terms of mediating the effect of satisfaction on place attachment. Conclusions - It is noted in this study that government support is required to preserve traditional markets and renewal program. Community requires multilateral communication and the formation of effective relationships. In contrast to the economic value emphasized by large retailers, the empirical analysis of the non-economic effects of traditional markets has presented the significance of socio-cultural values in traditional markets. In the future, socio-cultural values and economic values should be integrated into more empirical studies through mutual comparison. Investigating the increase and decrease of social value in traditional markets will help the future formulation in government policy.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.12
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• pp.703-710
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• 2020

The stock market serves as a representation of economic well-being in a country. Along with the myriad of economic predictors, specific knowledge possession may lead to different macro consequences of stock performance and market value. This study empirically investigates the capacity of possessing excellent intellectual capital to increase the performance and values of listed banks in Indonesia. The selection of banks as the primary data represents such sectors' capability to attract, employ, or exploit the excellent internal capacity under the discussion of resource-based view theory. At best to the authors' knowledge, this topic's findings are still elusive and debatable upon considering the direct and indirect relationships between the proposed exogenous and endogenous variables. Eighteen listed banks form the panel data throughout 2011-2016. This study employs a path analysis and Sobel test to obtain the results of the proposed hypothesis. The results report some positive relationships of the intellectual capital to firms' performances and values, directly and indirectly, with a substantial effect on the second model compared to the first model. This study highlighted knowledge's capacity as a vital basis to gauge the banks' performance and valuation. However, a better formulation of intellectual capital is required to capture a better measurement.

• Journal of the Korean Home Economics Association
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• v.28 no.3
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• pp.147-160
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• 1990

Family researchers had devoted little attention to Choice, Exchange theory by the time 1960. Being anchored by Thibaut & kelley(1959), this theory becomes one of the most widely used theoretical frameworks for family research. Waller's(1938) famous rating-dating hypothesis was intrinsically an exchange formulation. Blood and Wolfe(1960) employed the concept of rewards in their theory of family power. Farber(1964) also used the reward concept in his theory of permanent availability. Heer's(1964) specific application of its concepts to spousal power was among its earliest uses in the family. The general principle or most general proposition of the theory is that humans avoid costly behavior and seek rewarding statuses, to the end maxmize profits. This review will attempt to show that Choice, Exchange theory is applicable to the several arenas of family interaction and that it can provide an explanation for family behavior. Subjects such as mate selection, marital unstability, family cohesion, spousal power, the problems of aged, family co-unseling, and so on are included. By discussing research findings from a perspective of rewrds and costs this review will show that the application of the theory is not limited to one or two substative specialities with in the family domain. After all Choice, Exchange theory is truly general and can be productively applied to any domain of human behavior.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.8
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• pp.599-611
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• 2020

The purpose of this study is to explore and empirically analyze the factors affecting the financial performance of Korean small- and medium-sized manufacturing companies, which are relatively insufficiently researched, in terms of human resource management (HRM). In particular, this study intends to examine the human resource management activities focusing on the individual influences of workers' attitudes on systems and policies as well as jobs and organizations. This study reviews previous research and discussions on the human resource management system, as well as the organization and job-related attitudes and financial performance of workers, for the formulation of two hypotheses. Among the HCCP data, the hypothesis was verified through reliability and correlation analysis and stepwise multiple regression analysis for small- and medium-sized manufacturing enterprises. The results show, firstly, that human resource systems and systems have the same effect, but there were differences in the degree of impact. Secondly, job satisfaction has a statistically significant influence on financial performance. Lastly, all worker/employee attitude determinants are statistically significant for both job satisfaction and organizational commitment. HRM, previously relatively overlooked, provided theoretical and practical implications by demonstrating the direct impact on financial performance and the impact of individual human resource management systems and policies.

• Structural Engineering and Mechanics
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• v.17 no.6
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• pp.751-766
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• 2004

This paper extends the use of the hierarchic degenerated shell element to geometric non-linear analysis of composite laminated skew plates by the p-version of the finite element method. For the geometric non-linear analysis, the total Lagrangian formulation is adopted with moderately large displacement and small strain being accounted for in the sense of von Karman hypothesis. The present model is based on equivalent-single layer laminate theory with the first order shear deformation including a shear correction factor of 5/6. The integrals of Legendre polynomials are used for shape functions with p-level varying from 1 to 10. A wide variety of linear and non-linear results obtained by the p-version finite element model are presented for the laminated skew plates as well as laminated square plates. A numerical analysis is made to illustrate the influence of the geometric non-linear effect on the transverse deflections and the stresses with respect to width/depth ratio (a/h), skew angle (${\beta}$), and stacking sequence of layers. The present results are in good agreement with the results in literatures.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.7
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• pp.423-431
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• 2021

This research (1) examines the effect of stock ownership structure on capital structure; (2) explains the effect of stock ownership structure on corporate value; and (3) investigates the influence of capital structure on corporate value. This research is categorized as a quantitative research, which is directed to test various theories. In this study, the population of all consumption companies listed on the Indonesia Stock Exchange (IDX) consist of 38 companies. Population data in this study are all consumption companies, which have gone public in the period from 2010 to 2015. In this study, given the objectives and problem formulation and hypothesis, the analysis method used is Generalized Structural Component Analysis (GSCA). Ownership structure has a significant effect on capital structure; ownership structure has no significant effect on corporate value; capital structure has a significant effect on corporate value; corporate value has a significant effect on capital structure. Previous research found different results. Some researchers found a positive relationship and other researchers found a negative relationship, and there are studies that found both significant and non-significant effects. The inconsistency of previous research results prompted the researchers to examine the effect of ownership structure on capital structure and corporate value.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.17 no.4
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• pp.375-387
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• 2004

A new finite element model will be presented to analyze the nonlinear behavior of RC beams and slabs strengthened by a patch repair. The numerical approach is based on the p-version degenerate shell element including theory of anisotropic laminated composites, theory of materially and geometrically nonlinear plates. In the nonlinear formulation of this model, the total Lagrangian formulation is adopted with large deflections and moderate rotations being accounted for in the sense of von Karman hypothesis. The material model is based on hardening rule, crushing condition, plate-end debonding strength model and so on. The Gauss-Lobatto numerical quadrature is applied to calculate the stresses at the nodal points instead of Gauss points. The validity of the proposed p-version nonlinear finite element model is demonstrated through the load-deflection curves, the ultimate loads, and the failure modes of RC beams or slabs bonded with steel plates or FRP plates compared with available result of experiment and other numerical methods.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.3
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• pp.491-499
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• 2002

A p-version finite element model based on degenerate shell element is proposed tot the analysis of orthotropic laminated plates. In the nonlinear formulation of the model, the total Lagrangian formulation is adopted with large deflection and moderate rotation being accounted tot in the sense of yon Karman hypothesis. The material model is based on the Huber-Mises yield criterion and Prandtl-Reuss flow rule in accordance with the theory of strain hardening yield function, which is generalized lot anisotropic materials by introducing the parameters of anisotropy. The model is also based on extension of equivalent-single layer laminate theory(ESL theory) with shear deformation, leading to continuous shear strain at the interface of two layers. The integrals of Legendre polynomials are used for shape functions with p-level varying from 1 to 10. Gauss-Lobatto numerical quadrature is used to calculate the stresses at the nodal points instead of Gauss points. The validity of the proposed P-version finite element model is demonstrated through several comparative points of iew in terms of ultimate load, convergence characteristics, nonlinear effect, and shape of plastic tone.