• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제18권4호
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• pp.317-335
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• 2014

In this work, we investigate the global stability analysis of a viral infection model with antibody immune response. The incidence rate is given by a general function of the populations of the uninfected target cells, infected cells and free viruses. The model has been incorporated with two types of intracellular distributed time delays to describe the time required for viral contacting an uninfected cell and releasing new infectious viruses. We have established a set of conditions on the general incidence rate function and determined two threshold parameters $R_0$ (the basic infection reproduction number) and $R_1$ (the antibody immune response activation number) which are sufficient to determine the global dynamics of the model. The global asymptotic stability of the equilibria of the model has been proven by using Lyapunov theory and applying LaSalle's invariance principle.

• The Journal of Korean Physical Therapy
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• 제25권3호
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• pp.143-148
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• 2013

Purpose: The purpose of this study was to investigate whether changes in electromyography (EMG) activations of spinal stability muscles with respiratory demand change were due to changes in respiratory demand or in postural demand. Methods: Forty healthy subjects (19male, 21female, $20.8{\pm}1.9$years old) performed quiet breathing and four different forced respiratory maneuvers (FRM) (Pulsed Lip Breathing, Diaphragmatic Breathing, Combination breathing, and respiratory muscle endurance training breathing) while in sitting and standing positions. EMG data for four muscles (TrA/IO, EO, RA, and ES) were collected and filtered using a band pass filter (20~200Hz) and a notch filter (60, 120, 180Hz). Results: There were no significant differences on percentage of change on %MVIC between QB and FRM (PLB, CB, DB, and RMET) between positions (all p>0.05).

• 대한수학회보
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• 제44권4호
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• pp.825-840
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• 2007

In this paper, we will find out the general solution and investigate the generalized Hyers-Ulam-Rassias stability problem for the following cubic functional equation 3f(x+3y)+f(3x-y)=15f(x+y)+15f(x-y)+80f(y). The concept of Hyers-Ulam-Rassias stability originated from Th. M. Rassias# stability theorem that appeared in his paper: On the stability of the linear mapping in Banach spaces, Proc. Amer. Math. Soc. 72(1978), 297-300.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2006년도 춘계 학술발표회 논문집
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• pp.634-643
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• 2006

This study was intended to develop a high reliable technique by statistically processing on-site data with a general linear model, providing the basic data for construction, analysis of stability and establishment of maintenance measures for tunnel portal slopes in the future. This study evaluated the stability of a tunnel portal slope using a quantified technique, which is based on a general linear model. The important scores of each independent variable were allocated by using the ranges of the quantified values, based on the predicted coefficient of regression and the scores for categories of each independent variable were allocated so that those are equally spaced. The quantification model obtained from the results of evaluating the total data used for the quantification process provided precise results. In addition, it is expected that a more detail subdivision of response variables and sufficient data would produce a better stability evaluation standard.

• 대한수학회보
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• 제47권3호
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• pp.491-502
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• 2010

In this paper, we obtain the general solution and the generalized Hyers-Ulam Rassias stability of the functional equation f(2x + y) + f(2x - y) = 4(f(x + y) + f(x - y)) - $\frac{3}{7}$(f(2y) - 2f(y)) + 2f(2x) - 8f(x).

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집(한일합동학술편); 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.827-831
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• 1987

The analysis of a certian example and simulations given in the previous sections show that the modified FKA is more stable than the standard FKA without loss of the performance of it. The general analysis of modified FKA's numerical stability is the open problem with more simulations in order to prove the stability of it.

• 전기학회논문지
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• 제59권4호
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• pp.788-792
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• 2010

The problem of delay-dependent and parameter-dependent robust stability condition for discrete-time uncertain singular systems with polytopic uncertainty and interval time-varying delay is considered. A new robust stability condition based on parameter-dependent Lyapunov function is derived in terms of LMI (linear matrix inequality). Moreover, the proposed robust stability condition is a general condition for both singular and non-singular systems. A numerical example is presented to demonstrate the effectiveness of the proposed method.

• 호남수학학술지
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• 제29권1호
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• pp.61-74
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• 2007

Th. M. Rassias obtained the Hyers-Ulam stability of the general Euler-Lagrange functional equation. In this paper we prove the stability of generlized Euler-Lagrange functional equations in the spirit of Hyers, Ulam, Rassias and G$\breve{a}$vruta.

• 충청수학회지
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• 제26권2호
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• pp.367-375
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• 2013

In this paper, we investigate the stability for the functional equation $$f(x+y+z)+f(x-y)+f(x-z)-f(x-y-z)-f(x+y)-f(x+z)=0$$ in non-Archimedean normed spaces.

• 대한수학회논문집
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• 제33권3호
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• pp.1039-1048
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• 2018

In this paper we study the dynamics of a general ${\omega}-periodic$ model. Necessary and sufficient conditions for the global stability of zero steady state of the model are given. The conditions under which there exists a unique periodic solutions to the model are determined. We also show that the unique periodic solution is the global attractor of all other positive solutions. Some applications to mathematical models for cancer and tumor growth are given.