• Proceedings of the KIEE Conference
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• 2002.11d
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• pp.144-146
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• 2002

The latest development flow of MCCB(Molded Case Circuit Breaker) is largely separated from which are high capability of interrupting compact of size and multi-ability in functions. As follow of development of industrial system. MCCB which are including communication function and having a ultimate interrupting capability is required in electrical system. to attain an effective limitation of the peak let-through current and the let-through energy, the arc has to move rapidly off the contacts and has to increase the arc voltage which mainly effect to interrupt. In this paper. we made high performance circuit breaker which including current limiting unit which is attached to the main which is simulated by CAE tool that are repulsion force and mechanical dynamics after that we tested and finally selected optimized for circuit breaker.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.1
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• pp.304-320
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• 1996

A multiple production .epsilon. equation model was developed in the low Reynolds number $\kappa$-$\varepsilon$ model with the aids of DNS data. We derived the model theoretically and avoided the use of empirical correlations as much as possible in order for the model to have generality in the prediction of complex turbulent flow. Unavoidable model constants were, however, optimized with the aids of DNS data. All the production and dissipation models in the $\varepsilon$ equation were modified with damping functions to satisfy the wall limiting behavior. A new $f_{\mu}$ function, turbulent diffusion and pressure diffusion model for the k and .epsilon. equations were also proposed to satisfy the wall limiting behavior. By, computational investigation on the plane channel flows, we found that the multiple production model for .epsilon. equation could improve the near wall turbulence behavior compared with the standard production model without the complicated empirical modification. Satisfication of the wall limiting conditions for each turbulence model term was found to be most important for the accurate prediction of near wall turbulence behaviors.

• Korean Journal of Mathematics
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• v.23 no.4
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• pp.655-664
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• 2015

In this paper, we prove the discrete Hardy inequality through the continuous case for decreasing functions using elementary properties of calculus. Also, we prove the Carleman's inequality through limiting the discrete Hardy inequality with applications of Taylor series.

• Journal of the Korean Data and Information Science Society
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• v.21 no.2
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• pp.291-296
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• 2010

In this paper, we consider a versatile test based on percentile tests. The versatile test may be useful when the underlying distributions are unknown or quite different types. We consider two kinds of combining functions for the percentile statistics, the quadratic and summing forms and obtain the limiting distributions under the null hypothesis. Then we illustrate our procedure with an example. Finally we discuss some interesting features of the test as concluding remarks.

• English Language & Literature Teaching
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• no.4
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• pp.53-84
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• 1998

The purposes of the present study were to give the new direction of teaching English based on the 7th English curriculum, and to show some useful insights on English teaching in the 21st century. The 7th English curriculum was developed in two parts: as a required subject and as an elective subject. As a required subject, the English curriculum applies to the third grade of elementary school through to the first grade of high school. The elective subject of the English curriculum applies to the second and third grades of high school. In the 7th curriculum reform, a proficiency-based language program will be applied in the form of intensive and supplementary courses at the same levels irrespective of differences based on students' abilities, schools and regions. Linguistic functions, communicative functions, subject matters are included in the content area in language organization. Limiting the length of sentences is applied at elementary school only and is not applied at higher levels.

• Journal of Photoscience
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• v.6 no.2
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• pp.77-83
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• 1999

Calcium has a variety of functions in neuron and muscle cells and blood clotting, especially in the visual system where dark adapted rods cotransport with Na$\^$+/ into the cell. An influx of Ca$\^$++/ flows out of the cell through the Na$\^$+/-Ca$\^$++/ exchanger. By using a modified Using chamber in order to bring in vivo environment close, we have known that Ca$\^$++/ blocks the activity of guanylate cyclase, in consequence, having an effect on the amplitude of electroretinogram (ERG). We have measured the Ca$\^$++/, K$\^$+/, and Na$\^$+/ concentration in dark and light adapted bullfrog＇s (Rana catesbeiana) vitreous humor. The calcium concentration of the light adapted bullfrog＇s vitreous humor was higher than that of the dark adapted bullfrog＇s vitreous humor This means that ion activity between the photoreceptor and vitreous humor side is light dependent and we have found that a Ca$\^$++/ channel and Ca$\^$++/K$\^$+/ exchanger exist in the vitreous humor side. Taken together permeability of Ca$\^$++/, K$\^$+/ and K$\^$+/ ion internal limiting membrane faced in the vitreous humor side has light-dependent activity during the illumination.

• Journal of Electrical Engineering and Technology
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• v.3 no.4
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• pp.546-551
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• 2008

In this paper, a flux-lock type superconducting fault current limiter(SFCL) integrated with a voltage-controlled voltage source inverter(VC-VSI) is proposed. The suggested equipment, which consists of a flux-lock type SFCL and a VCVSI, can perform the fault current limiting operation from the occurrence of a short-circuit. In addition, it can compensate the reactive power that the non-linear load requires and also perform the uninterruptible power supply(UPS) as well as the load voltage stabilization by controlling the amplitude and the phase of the inverter's output voltage. The specification for a test model was determined and its various functions such as the fault current limiting and the power conditioning operations were presented and analyzed via computer simulation. Through the analytical results based on the computer simulation, the validity of the analysis was confirmed and its multi-operation was discussed.

• Journal of Auto-vehicle Safety Association
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• v.7 no.3
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• pp.30-34
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• 2015

This study examined the Korean drivers' acceptance of SAS(Speed Assistance systems) and traffic sign conditions in Korea roads for SLIF(Speed Limit Information Function) that is a part of SAS. Exceeding the speed limit is a factor in the severity of many road accidents and SAS would help the driver to observe a speed limit by warning and/or effectively limiting the speed of the vehicle. SAS are in the initial phase in Korea, Korean drivers could not be familiar with automatical speed limiting during driving, SAS interface design would be considered to be more readily acceptable to the public. And advanced SAS have been introduced onto the market which are able to inform the driver of the current speed limit based on camera and/or digital maps based SLIF. These systems are based on external data using sensors, so environmental conditions are an important factor which could cause malfunction of SLIF functions.

• Genomics & Informatics
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• v.17 no.4
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• pp.39.1-39.20
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• 2019

Analyzing patterns in data points embedded in linear and non-linear feature spaces is considered as one of the common research problems among different research areas, for example: data mining, machine learning, pattern recognition, and multivariate analysis. In this paper, data points are heterogeneous sets of biosequences (composite data points). A composite data point is a set of ordinary data points (e.g., set of feature vectors). We theoretically extend the derivation of the largest generalized eigenvalue-based distance metric D_ij(γ₁) in any linear and non-linear feature spaces. We prove that D_ij(γ₁) is a metric under any linear and non-linear feature transformation function. We show the sufficiency and efficiency of using the decision rule $\bar{{\delta}}_{{\Xi}i}$(i.e., mean of D_ij(γ₁)) in classification of heterogeneous sets of biosequences compared with the decision rules min_𝚵iand median_𝚵i. We analyze the impact of linear and non-linear transformation functions on classifying/clustering collections of heterogeneous sets of biosequences. The impact of the length of a sequence in a heterogeneous sequence-set generated by simulation on the classification and clustering results in linear and non-linear feature spaces is empirically shown in this paper. We propose a new concept: the limiting dispersion map of the existing clusters in heterogeneous sets of biosequences embedded in linear and nonlinear feature spaces, which is based on the limiting distribution of nucleotide compositions estimated from real data sets. Finally, the empirical conclusions and the scientific evidences are deduced from the experiments to support the theoretical side stated in this paper.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.21 no.2
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• pp.153-160
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• 2008

In this study, we propose a new three-node hybrid-mixed curved beam element with the relaxed-equiribrium stress functions for static analysis. The proposed element considering shear deformation is based on the Hellinger-Reissner variational principle. The stress functions are carefully chosen from three important considerations: (i) all the kinematic deformation modes must be suppressed, and (ii) the spurious constraints must be removed in the limiting behaviors via the field-consistency, and (iii) the relaxed equilibrium conditions could be incorporated because it might be impossible to select the stress functions and parameters to fully satisfy both the equiribrium conditions and the suppression of kinematic deformation modes in the three-node curved beam hybrid-mixed formulation. Numerical examples confirm the superior and stable behavior of the proposed element regardless of slenderness ratio and curvature. Besides, the proposed element shows the outstanding performance in predicting the stress resultant distributions.