• Structural Engineering and Mechanics
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• v.12 no.1
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• pp.35-50
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• 2001

A numerical methodology is presented in this paper for the geometrically non-linear analysis of slender uni-dimensional structural elements under unilateral contact constraints. The finite element method together with an updated Lagrangian formulation is used to study the structural system. The unilateral constraints are imposed by tensionless supports or foundations. At each load step, in order to obtain the contact regions, the equilibrium equations are linearized and the contact problem is treated directly as a minimisation problem with inequality constraints, resulting in a linear complementarity problem (LCP). After the resulting LCP is solved by Lemke's pivoting algorithm, the contact regions are identified and the Newton-Raphson method is used together with path following methods to obtain the new contact forces and equilibrium configurations. The proposed methodology is illustrated by two examples and the results are compared with numerical and experimental results found in literature.

• Korean Journal of Mathematics
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• v.31 no.4
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• pp.495-504
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• 2023

This article deals with non-degenerate linear transformations on Euclidean Jordan algebras. First, we study non-degenerate for cone invariant, copositive, Lyapunov-like, and relaxation transformations. Further, we study that the non-degenerate is invariant under principal pivotal transformations and algebraic automorphisms.

• Asia pacific journal of information systems
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• v.29 no.4
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• pp.690-716
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• 2019

Open innovation has attracted significant attention from both academics and practitioners. However, theoretical and empirical researchers disagree on how open innovation improves firm performance. The inconsistent results reported in the literature may be attributed to the fact that they failed to provide an integrative view of how to make use of internal and external knowledge to enhance innovation performance. Furthermore, although the adoption value of innovation approaches varies depending on firm size and IT capabilities, their impacts have not been adequately taken into consideration. Drawing on complementarity theory, this study revisits the research problem and develops eight hypotheses. Surveys collected from 339 Korean firms were analyzed to test the hypotheses using the supermodularity functions. The results indicated that an internal knowledge-oriented innovation approach has a positive impact on innovation performance regardless of firm size. However, an external knowledge-oriented innovation approach has a positive effect on innovation performance in large firms while having no significant effect on innovation performance of SMEs. Results also confirmed a complementary relationship between internal and external knowledge-oriented innovation approaches in large firms, whereas substitutable relationships were confirmed in SMEs. This study sheds new light on open innovation by identifying the role of different types of innovation approaches, firm size, and IT capabilities.

• Journal for History of Mathematics
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• v.28 no.5
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• pp.263-278
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• 2015

As intuition is more unreliable than logic or reason, its studies in mathematics and mathematics education have not been done that much. But it has played an important role in the invention and development of mathematics with logic. So, it is necessary to recognize and explore the value of intuition in mathematics education. In this paper, I investigate the function and role of intuition in terms of mathematical learning and problem solving. Especially, I discuss the positive and negative aspects of intuition with its characters. The intuitive acceptance is decided by self-evidence and confidence. In relation to the intuitive acceptance, it is discussed about the pedagogical problems and the role of intuitive thinking in terms of creative problem solving perspectives. Intuition is recognized as an innate ability that all people have. So, we have to concentrate on the mathematics education via intuition and the complementary between intuition and logic. For further research, I suggest the studies for the mathematics education via intuition for students' mathematical development.

• Proceedings of the KIEE Conference
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• 2001.07d
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• pp.2120-2122
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• 2001

This paper describes a PID controller for an attraction type magnetic levitation system considering $H^{\infty}$ performance. PID controllers are a kind of fixed structure reduced order controllers. Using change of variables a reduced order control problem can be recast into a static output feedback control problem and can be solved efficiently by LMI(Linear Matrix Inequality) method. In this paper, cone complementarity method is adopted and the simulation shows good results.

• Nonlinear Functional Analysis and Applications
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• v.28 no.2
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• pp.497-520
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• 2023

Numerous problems in science and engineering defined by nonlinear functional equations can be solved by reducing them to an equivalent fixed point problem. Fixed point theory provides essential tools for solving problems arising in various branches of mathematical analysis, such as split feasibility problems, variational inequality problems, nonlinear optimization problems, equilibrium problems, complementarity problems, selection and matching problems, and problems of proving the existence of solution of integral and differential equations.The theory of fixed is known to find its applications in many fields of science and technology. For instance, the whole world has been profoundly impacted by the novel Coronavirus since 2019 and it is imperative to depict the spread of the coronavirus. Panda et al. [24] applied fractional derivatives to improve the 2019-nCoV/SARS-CoV-2 models, and by means of fixed point theory, existence and uniqueness of solutions of the models were proved. For more information on applications of fixed point theory to real life problems, authors should (see [6, 13, 24] and the references contained in).

• Journal of Fisheries and Marine Sciences Education
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• v.21 no.2
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• pp.306-324
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• 2009

The purpose of this study is to analyze green growth issues such as employment, education and training, social capital and nature's standing right from the complementary perspective between natural environment conservation and economic growth. Green growth can be defined as a growth which lowers an increasing rate of entropy and at the same time improves our living standard. Green growth paradigm requires a quite amount of understanding the laws of thermodynamics and the uncertainty principle as the highest orders which regulate our overall socio-economic behaviors. They suggest that socio-economic growth is a mere transformation process of natural energy from one form to another and they increases natural manmade entropy over time. The most important issue of green growth policy may be a problem concerning employment and/or unemployment since green growth may induce inevitable movement of resources from the existing industries to the green sector. In particular, green industries will demand more highly specialized manpower than the existing ones. Without a well-designed new training education system and social capital accumulation toward environmental concerns, green growth may accompany a substantial amount of structural involuntary frictional unemployment. This may increase not only wealth-distribution disparity but also political instability. In order to achieve harmonious green growth, we should recognize that there are important complementary relationships between green and growth. Our society should also be able to innovate the existing educational system to accumulate social capital, to create a new sharing system, and to admit nature's standing right. Although the 2003 lawsuit case of Korean Salamander in Cheonseong Mountain went against plaintiff, it would provide apparently our society with a way of green development ahead.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.4
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• pp.95-106
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• 2017

In this paper, we investigate the conventional topological interference management (TIM) with proposed network topology such as 8 trigram (8 user networks). The key observation is that optimal symmetric degree of freedom (DoF) can be achieved for 8 user network with different channel coherence times by adaptively selecting the interference alignment scheme via controlling the alignment feasibility of the transmitted signals. However, this yields a very complex problem, for which we use the combination of different schemes such as interference avoidance and repetition coding. In addition to the above schemes, we propose a triangular transmit cooperation (TTC) algorithm for 8 user networks to achieve the optimal symmetric DoF. And We apply the principle of complementarity of 8 trigram to remove the interferences, and correspond the concepts of win-win and conflict to direct and indirect signals of transmit and receive respectively. We find that the principle of complementarity comes out from the trigram of I Ching. That is, we apply the relation of confrontation and coexistence to 8 transmitters and receivers, and get the results of symmetric DoF of 4/3.

• Environmental and Resource Economics Review
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• v.16 no.2
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• pp.275-311
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• 2007

Hydrogen energy is emphasized as a substitutable energy of carbon-based energy system in the future, since it is non-depletable and clean energy. Long term vision of Korean government on the national energy system is to promote hydrogen energy by 15% of final energy demand until 2040. This study analyzes economic impacts of hydrogen energy development employing a dynamic CGE model for Korea. Frontier technology such as hydrogen energy is featured as slow diffusion at the initial stage due to the learning effect and energy complementarity. Without government intervention, hydrogen energy would be produced upto 6.5% of final energy demand until 2040. However, if government subsidizes sales price of hydrogen energy by 10%, 20%, and 30%, share of hydrogen energy would increase 9.2%, 15.2%, and 37.7% of final energy demand. This result shows that the slow diffusion problem of hydrogen energy as frontier technology could be figured out by market incentive policy. On the other hand, production levels of transportation sector would increase while growth rate of oil and electricity sectors would decline. Household consumption would be affected negatively since increase of consumption due to the price decrease would be overwhelmed by income reduction owing to the increase of tax. Overall, GDP would not decrease or increase significantly since total production, investment, and export would increase even if household consumption declines.

• The Transactions of the Korean Institute of Electrical Engineers A
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• v.51 no.4
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• pp.196-201
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• 2002

An important aspect of the study of power system markets involves the assessment of strategic behavior of participants for maximizing their profits. In models for imperfect competition of a deregulated system, the key tack is to find the Nash equilibrium. When the constraints are not considered in the power market, the equilibrium has the form of a pure strategy. However, the constraints are considered, the equilibrium has the form of a mired strategy. In this paper the bimatrix game approach leer finding a mixed equilibrium is analyzed. The Nash equilibrium of a mixed strategy will be used adequately for the analysis of market power.