• Membrane and Water Treatment
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• v.13 no.4
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• pp.167-172
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• 2022

The analytical results are presented for the mass transfer in a cylindrical pore covering from the macroscale, multiscale to nanoscale owing to the variation of the inner diameter of the pore. When the thickness h_bf of the physically adsorbed layer potentially fully formed on the pore wall is comparable to but less than the inner radius R₀ of the pore, the multiscale flow occurs consisting of both the nanoscale non-continuum adsorbed layer flow and the macroscopic continuum liquid flow; When R₀ ≤ h_bf, the flow in the whole pore is essentially non-continuum; When R₀ is far greater than h_bf, the flow in the whole pore can be considered as macroscopic and continuum and the adsorbed layer effect is negligible.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.2
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• pp.83-93
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• 2008

Assessing for flora distribution is necessary for land management and environmental research in reclaimed lands. This study was conducted to find out the relationship between vegetation distribution and soil salinity on three reclaimed tidal flats of Kyonggi-bay in the mid-west coast of Korea. We investigated the soil salinity and identified the vegetation at the continuum distribution spots, and describe the characteristics of continuum distribution. On the reclaimed tidal flats, spatial variation of vegetation formed partially, however as the result for connection of each spatial variation along with the soil salinity, continuum distribution formed and it was overlapped edaphic gradient with vegetation distribution, it means that the continuum distribution correspond with soil salinity gradient, as the evidence high salt tolerance species occurred at high saline spots, non salt tolerance species occurred at low saline spots. On the aged reclaimed tidal flats, continuum type was various and also clearly distinguished but it was not clear on the early stage of reclamation. The continuum distribution distinguished sequential and non-sequential type. Sequential type started from high saline zone and connected to low saline zone gradually, on this type, vegetation changed from pioneer halophyte to facultative halophyte and glycophyte along with the salinity gradient. Non-sequential type formed by non-sequential change of soil salinity, on this type, vegetation distribution was non-regular form because it has not changed gradually. In the aged reclaimed land, vegetation wilted zone existed with high salinity, and continuum distribution started from this zone with bare patch.

• Journal of Korean Society of Archives and Records Management
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• v.21 no.3
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• pp.1-16
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• 2021

Record continuum is a theory providing the basis for archival science in the paradigm shift to the electronic record environment. However, critical analysis of it has been hardly performed so far, as it is still in development, and its core is a new perspective on records different from the life cycle model. Therefore, for further understanding of the significance and limitations of record continuum in the electronic record environment and performance of more in-depth theoretical development, an analysis of the meaning and nature of records contained in record continuum logic is essential. Given that record continuum does not define a record separately, the meaning and nature of records it contains in the recent electronic record environment are examined through the analysis of axis and dimension in a record continuum model.

• Steel and Composite Structures
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• v.21 no.3
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• pp.501-515
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• 2016

Seismic analysis for steel frame structure with brace configuration using topology optimization based on truss-like material model is studied. The initial design domain for topology optimization is determined according to original steel frame structure and filled with truss-like members. Hence the initial truss-like continuum is established. The densities and orientation of truss-like members at any point are taken as design variables in finite element analysis. The topology optimization problem of least-weight truss-like continuum with stress constraints is solved. The orientations and densities of members in truss-like continuum are optimized and updated by fully-stressed criterion in every iteration. The optimized truss-like continuum is founded after finite element analysis is finished. The optimal bracing system is established based on optimized truss-like continuum without numerical instability. Seismic performance for steel frame structures is derived using dynamic time-history analysis. A numerical example shows the advantage for frame structures with brace configuration using topology optimization in seismic performance.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.6
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• pp.681-691
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• 2011

The size distributions of smoke particles from fire are prerequisite for the studies on fire detection and adverse health effects. Above the flame of the fire, coagulation dominates and the smoke particles grow from 1 to 50 nm up to 100 to 3,000 nm, sizes ranging from the free-molecular regime to the continuum regime. The characteristics of the agglomeration of the smoke particles are well known, independently for each of the free-molecular and continuum regimes. However, there are not many systematic studies in the entire regime by the complexity of the mechanisms. The purpose of this work is to find the characteristics of the development of the size distribution of smoke particles by agglomeration in the entire size range covering the free-molecular regime, via transition regime, to the near-continuum and continuum regime for each variation of parameters such as fractal dimension, primary particle size and dimensionless coagulation time. In this work, the dynamic equation for the discrete-size spectrum of the particles was solved using a nodal method based on the modification of a sectional method. In the calculation, the collision frequency function for the entire regime, which is derived by using the concept of collision volume and general enhancement function, was applied. The self-preserving size distribution for the entire regime is compared with the ones for the free-molecular or continuum regimes for each variation of the parameters.

• Nuclear Engineering and Technology
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• v.49 no.5
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• pp.1006-1009
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• 2017

We discuss the problems of scattering in this framework, and show that the applied method is very useful in the investigation of the effect of the resonance in the observed scattering cross sections. In this study, not only the scattering cross sections but also the decomposition of the scattering cross sections was computed for the ${\alpha}-{\alpha}$ system. To obtain the decomposition of scattering cross sections into resonance and residual continuum terms, the complex scaled orthogonality condition model and the extended completeness relation are used. Applying the present method to the ${\alpha}-{\alpha}$ and ${\alpha}-n$ systems, we obtained good reproduction of the observed phase shifts and cross sections. The decomposition into resonance and continuum terms makes clear that resonance contributions are dominant but continuum terms and their interference are not negligible. To understand the behavior of observed phase shifts and the shape of the cross sections, both resonance and continuum terms are calculated.

• Journal for History of Mathematics
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• v.33 no.6
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• pp.327-343
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• 2020

This study investigate philosophical discussions related to the Zeno's paradoxes in order to derive the mathematics educational implications. The paradox of Zeno's motion is sometimes explained by the calculus theories. However, various philosophical discussions show that the resolution of Zeno's paradox by calculus is not a real solution, and the concept of a continuum which is composed of points and the real number continuum may not coincide with the physical space and time. This is supported by the fact that the hyperreal number system of nonstandard analysis could be another model of a straight line or time and that an alternative explanation of Zeno's paradox was possible by the hyperreal number system. The existence of two different theories of the continuum suggests that teachers and students may not have the same view of the continuum. It is also suggested that the real world model used in school mathematics may not necessarily match the student's intuition or mathematical practice, and that the real world application of mathematics theory should be emphasized in education as a kind of 'correspondence.'

• Journal of The Korean Astronomical Society
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• v.38 no.2
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• pp.223-226
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• 2005

We present the results of a 21cm radio continuum aperture synthesis mosaic of the Large Magellanic Cloud (LMC), made by combining data from 1344 separate pointing centers using the Australia Telescope Compact Array (ATCA) and the 64-m Parkes single-dish telescope. The resolution of the mosaicked images is 55' ( 10 pc, using a distance to the LMC) and a region $10^{\circ}{\times}12^{\circ}$ is surveyed.

• Journal of the Chungcheong Mathematical Society
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• v.28 no.4
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• pp.647-651
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• 2015

Let (X, d) be a compact metric space, and let $f:X{\rightarrow}X$ be a continuous map. We consider that if a positively continuum-wise expansiveness continuous map f has the positively shadowing property in the nonwandering set, then the topological entropy is positive.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.227-234
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• 2003

In this study, an equivalent continuum model for single wall carbon nanotube is proposed. The model links interatomic potentials and atom structure of a materials to a constitutive model on the continuum level. The Young's modulus and shear modulus were predicted by the model. The predictions were in good agreement with the prior experimental results available in the literatures. Also, the strain energy of the carbon nanotube was predicted as a function of the radius of the carbon nanotube.