• Journal for History of Mathematics
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• v.21 no.3
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• pp.1-30
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• 2008

The success of Newton's Gravitational Theory has influenced the theory of capillarity, beginning in the early nineteenth century, by providing a major model of molecular attraction. He used the equation of the attraction of spheroids, which is expressed by second order partial differential equations, to utilize this analogy as the same kind of a particle's force, between gravitational, refractive force of light, and capillarity. The solution of the differential equation corresponds to the geometrical figure of the vessel and the contact angle which is made by the fluid. Unknown abstract functions $\varphi(f)$ represent interaction forces between molecules, giving their potential functions. By conducting several kinds of experimental conditions, it was found that the height of the ascending fluid in the tube is inversely proportional to the rayon of the tube or the distance of the plate. This model is an essential element in the theory of capillarity. Laplace has brought Newtonian mechanics to completion, which relates to the standard model of gravitational theory. Laplace-Young's equation of capillarity is applicable to minimal surfaces in mathematics, to surface tensional phenomena in physics, and to soap bubble experiments.

• Bulletin of the Korean Chemical Society
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• v.7 no.5
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• pp.388-391
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• 1986

There are lipid phase theories and aqueous phase theories among the theories of anesthesia. For water clusters induced by anesthetizing molecules, the interaction energies are calculated using an empirical potential function and correlated with the anesthetizing partial pressures for mice. A good agreement was obtained with the theory that the water clusters around anesthetics play an important role on the anesthetic actions.

• Journal of Information Technology Applications and Management
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• v.13 no.4
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• pp.13-39
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• 2006

The primary purpose of this study is to examine the interaction effects of organizational characteristics as contextual variables on the relationship between relational exchange characteristics and ASP service performance. The effect of relational exchange characteristics on ASP service performance has been also investigated. For this purposes, we developed a research model based on the literature reviews of ASP services, relational exchange theory, and contingency theory. A total of 106 usable survey responses from companies using ASP services has been analyzed in the study. The findings indicate that (1) flexibility and partnership had a positive influence upon noneconomic profit, (2) information sharing had a positive influence upon economic profit, (3) organizational size and IS maturity had a partial moderating effect on the relationship between relational exchange characteristics and ASP service performance, and (4) the subgroup analysis, conducted to determine the exact nature of interaction effect, reveals that the relationship between relational exchange characteristics and noneconomic profit is significantly stronger with a high level of organizational size than with a low level, and that the relationship between relational exchange characteristics and economic profit is significantly stronger with a low level of IS maturity than with a high level.

• Structural Engineering and Mechanics
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• v.68 no.1
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• pp.103-119
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• 2018

In the present research, an attempt is made to obtain a semi analytical solution for both nonlinear natural frequency and forced vibration of embedded functionally graded double layered nanoplates with all edges simply supported based on nonlocal strain gradient elasticity theory. The interaction of van der Waals forces between adjacent layers is included. For modeling surrounding elastic medium, the nonlinear Winkler-Pasternak foundation model is employed. The governing partial differential equations have been derived based on the Mindlin plate theory utilizing the von Karman strain-displacement relations. Subsequently, using the Galerkin method, the governing equations sets are reduced to nonlinear ordinary differential equations. The semi analytical solution of the nonlinear natural frequencies using the homotopy analysis method and the exact solution of the nonlinear forced vibration through the Harmonic Balance method are then established. The results show that the length scale parameters give nonlinearity of the hardening type in frequency response curve and the increase in material length scale parameter causes to increase in maximum response amplitude, whereas the increase in nonlocal parameter causes to decrease in maximum response amplitude. Increasing the material length scale parameter increases the width of unstable region in the frequency response curve.

• Nuclear Engineering and Technology
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• v.42 no.4
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• pp.450-459
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• 2010

The present paper investigates the collapse pressure of cylinders with intermediate thickness subjected to external pressure based on detailed elastic-plastic finite element (FE) analyses. The effect of the initial ovality of the tube on the collapse pressure was explicitly considered in the FE analyses. Based on the present FE results, the analytical yield locus, considering the interaction between the plastic collapse and local instability due to initial ovality, was also proposed. The collapse pressure values based on the proposed yield locus agree well with the present FE results; thus, the validity of the proposed yield locus for the thickness range of interest was verified. Moreover, the partial safety factor concept based on the structural reliability theory was also applied to the proposed collapse pressure estimation model, and, thus, the priority of importance of respective parameter constituting for the collapse of cylinders under external pressure was estimated in this study. From the application of the partial safety factor concept, the yield strength was concluded to be the most sensitive, and the initial ovality of tube was not so effective in the proposed collapse pressure estimation model. The present deterministic and probabilistic results are expected to be utilized in the design and maintenance of cylinders subjected to external pressure with initial ovality, such as the once-through type steam generator.

• Journal of Families and Better Life
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• v.8 no.2
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• pp.147-162
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• 1990

The purpose of this review is to establish a groundwork for building a more comprehensive conceptual framework within which various aspects of sibling relations and factor related to sibling behaviors con be explained and integrated. Descriptions of the trends and shifts in sibling studies are made in terms of their themes, variables, basic perceptions and general approaches, and analyzes of current state of sibling researches are made with relation to the conceptual aspects of the studies, namely, their standpoints on the issues of sibling variations, the sources of variations, and basic units of analysis, their reliance or emphasis on different methods, and their interests in the mediation processes. It is recognized that research variables have been successively differentiated and used in diversified manners and family ecology and systems theory viewpoints have been incorporated into the understanding of sibling relations. A triad in its full meaning, rather than a dyad or a partial trial, is proposed as a unit of analysis in order for the researchers to be able to examine and describe the true interactional aspects of family relations involving sibling relations. The concepts of coexistence and interaction are proposed as key concepts os that the inconsistencies in findings, differing viewpoints, contradicting conceptions , and contrasting approaches can be interpreted and integrated into a unified system of theories on siblings. The coexistence of similarities and differences in reality. the inevitability of interaction between individual variables and environmental variables and between within-family environmental factors and our-of-family environmental factors, and the need for the joint use of intrafamilial and extrafamilial approach are acknowledged. Attention is also drawn to the mechanism characteristics and the directionality of the mediating processes of mediating variables between a variable and its effects.

• Asia pacific journal of information systems
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• v.16 no.4
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• pp.103-119
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• 2006

One of the most important reasons for using online game is intrinsic motivation which relates the drive to perform a behavior for perceptions of pleasure and satisfaction from the behavior itself. Therefore, most studies for using online game have been based on theories for intrinsic motivation such as flow. However, such theories have some limitations for explaining social aspects of online games such as Massively Multiplayer Online Role Game (MMORPG), which provides a society for game players by using a virtual space for playing games so called 'persistent world'. Adaptive structuration theory (AST) is one of trying to capture the change of using IT due to social interactions between users and system. In order to explain online game players' behavior considering social interaction, we suggest a research model based on AST. Our model aims to investigate the relationship between appropriation which is determined by faithfulness of appropriation (FOA) and consensus on appropriation (COA) and performance which is represented by the relationship among perceived winning, flow, and intention of reuse. An empirical test of our model for 125 MMORPG users which is analyzed by Partial Least Square method shows very satisfactory and interesting results. While hypotheses suggested in our model are supported, the influence of COA on game performance is shown to be stronger than that of FOA.

• Interaction and multiscale mechanics
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• v.2 no.3
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• pp.223-233
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• 2009

This paper presents a new nonlocal stress variational principle approach for the transverse free vibration of an Euler-Bernoulli cantilever nanobeam with an initial axial tension at its free end. The effects of a nanoscale at molecular level unavailable in classical mechanics are investigated and discussed. A sixth-order partial differential governing equation for transverse free vibration is derived via variational principle with nonlocal elastic stress field theory. Analytical solutions for natural frequencies and transverse vibration modes are determined by applying a numerical analysis. Examples conclude that nonlocal stress effect tends to significantly increase stiffness and natural frequencies of a nanobeam. The relationship between natural frequency and nanoscale is also presented and its significance on stiffness enhancement with respect to the classical elasticity theory is discussed in detail. The effect of an initial axial tension, which also tends to enhance the nanobeam stiffness, is also concluded. The model and approach show potential extension to studies in carbon nanotube and the new result is useful for future comparison.

• Structural Engineering and Mechanics
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• v.53 no.4
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• pp.625-644
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• 2015

In this paper, a two-layer partial interaction composite beams model considering the higher order shear deformation of sub-elements is built. Then, the governing differential equations and boundary conditions for static analysis of linear elastic higher order composite beams are formulated by means of principle of minimum potential energy. Subsequently, analytical solutions for cantilever composite beams subjected to uniform load are presented by Laplace transform technique. As a comparison, FEM for this problem is also developed, and the results of the proposed FE program are in good agreement with the analytical ones which demonstrates the reliability of the presented exact and finite element methods. Finally, parametric studies are performed to investigate the influences of parameters including rigidity of shear connectors, ratio of shear modulus and slenderness ratio, on deflections of cantilever composite beams, internal forces and stresses. It is revealed that the interfacial slip has a major effect on the deflection, the distribution of internal forces and the stresses.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.10a
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• pp.374-379
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• 1994

This paper deals with the problem of plate separation and anchorage at the ends of steel plates strengthened by EBSP. Test results show that the reinforced concrete beams strengthened by EBSP occurs the premature failure without the beams achieving their full flexural strength at the end of plates. The premature failure is the cause of stress concentrations in the adhesive layer of plate, reinforced concrete incase of lack of plate length. Then a simple, approximate procedure for predicting the shear and normal stress concentrations is investigated by Robert's the ory based on partial interaction theory. The theoretical results are compared, and show close agreement with test results. A method is derived for determining the plate length that prevents the premature anchorage zone failure