• Journal of the Korean Society of Physical Medicine
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• v.5 no.1
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• pp.15-24
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• 2010

Purpose : The purpose of this study was to investigate the effect of loading position on plantar center of pressure(COP) displacement when carrying a schoolbag during walking. Methods : Forty-four normal subjects were randomly assigned to five groups according to the method of carrying a schoolbag. The carrying a schoolbag methods were classified into five conditions: no bag (condition 1), a backpack (condition 2), a shoulder bag (condition 3), a cross bag (condition 4), a one-hand bag (condition 5). COP displacement such as anteroposterior distance and mediolateral distance of COP were measured with F-scan system. The repeated one-way analysis of variance (ANOVA) and independent t-test were used to confirm the statistical significance. Results : In the comparison of parameters of COP displacement between conditions, anteroposterior distance and mediolateral distance in the left foot and mediolateral distance in the right foot were not significantly different(p>.05), but anteroposterior diatance in the right foot was significantly different(p>.05). Between left and right foot, at condition 1 and 5 the mediolateral distance of COP was significantly different(p<.05) but anteroposterior distance at condition 1 and 5, anteroposterior distance and mediolateral distance of COP at condition 2, 3 and 4 were not significantly different(p>.05). Conclusion : These findings showed that the various loading position by five types of carrying a schoolbag didn't have influence significantly on COP displacement on during walking because of mechanism of postural adaption.

• Water Engineering Research
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• v.1 no.2
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• pp.119-127
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• 2000

In the process of crossflow microfiltration, a deposit of cake layer tends to form on the membrane, which usually controls the performance of filtration. It is found, however, that there exist a condition under which no deposit of cake layer is made. This condition is called the sub-critical flux condition, and the critical flux here means a flux below which a decline of flux with time due to the deposit of cake layer does not occur. In order to study the characteristics of the critical flux, a numerical model is developed to predict the critical flux condition, and is verified with experimental results. For development of the model, the concept of effective particle diameter is introduced to find a representative size of various particles in relation to diffusive properties of particles. The model is found to be in good match with the experimental results. The findings from the use of the model include that the critical flux condition is determined by the effective particle diameter and the ratio of initial permeate flux to crossflow velocity.

• Korean Journal of Mathematics
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• v.17 no.1
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• pp.53-66
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• 2009

We show the existence of a nontrivial periodic solution for the superquadratic parabolic equation with Dirichlet boundary condition and periodic condition with a superquadratic nonlinear term at infinity which have continuous derivatives. We use the critical point theory on the real Hilbert space $L_2({\Omega}{\times}(0 2{\pi}))$. We also use the variational linking theorem which is a generalization of the mountain pass theorem.

• English Language & Literature Teaching
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• v.10 no.3
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• pp.21-40
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• 2004

This study Questioned what happens in L2 reading comprehension of the expository text, as measured by recall and inference-making abilities, when a L2 reader was induced to develop a content schema about the topic of a target text, but the structure of that schema departs from the structure of the target text Seventy-four. Korean university students read either the same version text twice (consistent condition) or two different version texts (inconsistent condition) with a three-day interval between the two readings. The results of a verification test indicate that, for those subjects with higher L2 reading proficiency, the inconsistent condition was more beneficial than the consistent condition for the inference-making task. On the other hand, for lower-level L2 readers, the consistent condition was more favorable for the recall task. It was concluded that inducing a structurally inconsistent schema through an L2 pre-reading would be beneficial only when the reader's L2 linguistic ability is proficient enough to produce necessary propositions from the pre-reading.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.12
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• pp.1372-1378
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• 2011

The smart air condition system is superior to conventional air condition system in the aspect of control accuracy, environmental preservation and it is foundation for intelligent vehicle such as electric vehicle, fuel cell vehicle. In this paper, failure analyses of smart air condition system will be performed and then sensor fusion technique will be proposed for fail safety of smart air condition system. A sensor fusion logic of air condition system by using CO sensor, $CO_2$ sensor and VOC, $NO_x$ sensor will be developed and simulated by fault injection simulation. The fusion technology of smart air condition system is generated in an experiment and a performance analysis is conducted with fusion algorithms. The proposed algorithm adds the error characteristic of each sensor as a conditional probability value, and ensures greater accuracy by performing the track fusion with the sensors with the most reliable performance.

• Kyungpook Mathematical Journal
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• v.45 no.2
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• pp.231-240
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• 2005

The paper shows that a hypersurface with constant curvature with the condition $hD{\subset}D$, of a contact metric manifold with a nullity condition and ${\varphi}-constant$ sectional curvature, has the curvature equals to k and ${\mu}=0$.

• Journal of the Chungcheong Mathematical Society
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• v.20 no.3
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• pp.327-332
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• 2007

A variational inequality defined by the second-order cone is considered, and it is shown that a necessary and sufficient condition for a solution of the variational inequality holds under some regularity condition.

• Bulletin of the Korean Mathematical Society
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• v.38 no.1
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• pp.175-182
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• 2001

In this paper we prove the existence and uniqueness of a mild solution of a functional differential equation with nonlocal condition using the semigroup theory and the Banach fixed point principle.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.4
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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.

• 제어로봇시스템학회:학술대회논문집
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• 1989.10a
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• pp.918-923
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• 1989

This paper presents a stability condition for Astrom's minimal variance control(MVC) with mismatch of time delay for a SISO ARMAX model containing time delay. The proof of the condition presented here is based on the characteristic equation in the feedback system and its magnitude. This condition, from easy numerical calculation, is able to find the stability of the feedback system without knowing the real time delay.