• Journal of Korean Society of Forest Science
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• v.29 no.1
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• pp.54-101
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• 1976

This study was conducted on the major factors affecting soil erosion and surface run-off. In order to investigate the processes and mechanisms of soil erosion on denuded forest-land in Korea, and to systematize the magnitudes of influences and interactions between individual factors, the five major factors adopted in these experiments are soil textures (coarse sand and clay loam), slope steepness ($10^{\circ}$, $20^{\circ}$, $30^{\circ}$ and $40^{\circ}$), rainfall intensities (50, 75 and 100mm/hr), slope mulching methods (bare, coarse straw-mat mulching, grass mulching and anti-erosion liquid mulching) and vegetation densities (sparse, moderate and dense). The processes and mechanisms of soil erosion, and the effects of mulchings on soil erosion as well as surface run-off rates were studied algebraically with four parts of laboratory experiments under the simulated rainfall and another part of field experiment under the natural rainfall. The results in this study are summarized as follows: 1. Experiment factors and surface run-off rates The surface run-off rates under the natural rainfall were resulted about 24.7~28.7% from the bare slopes, about 14.0~16.4% from the straw-mat mulched slopes, about 7.9~9.1% from the liquid mulched slopes, and about 5.6~7.2% from the grass mulched slopes respectively. The surface run-off rates under the simulated rainfall differed greatly according to the rainfall intensity and the mulching method. 2. Magnitudes of influences and interactions of the individual factor on the surface run-off rates. The experimental analyses on the major factors(soils, slopes, rainfalls, mulchings and vegetations) affecting the rates of surface run-off, show that the mean differences of surface run-off rate are significant at 5% level between the soil texture factors, among the slope steepness factors, among the rainfall intensity factors, among the mulching method factors, and among the vegetation density factors respectively. The interactions among the individual factor have a great influence(significant at 1% level) upon the rate of surface run-off, except for the interactions of the factors between soils and slopes; between slopes and vegetations; among soils, slopes and rainfalls; and among soils, slopes and mulchings respectively. On the bare slopes under the simulated rainfall, the magnitude of influences of three factors(soils, slopes and rainfalls) affecting the rate of surface run-off is in the order of the factor of rainfalls, soils and slopes. The magnitude of influences of three factors (soils, rainfalls and mulchings) affecting the rate of surface run-off, on the mulched slopes under the simulated rainfall is in the order of the factor of mulchings, rainfalls and soils and that of influences of the factor of soils, slopes and mulchings is in the order of the factor of mulchings, soils and slopes. On the vegetation growing slopes under the simulated rainfall, the magnitude of influences of three factors (soils, slopes and vegetations) affecting the rate of surface run-off is in the order of the factor of vegetations, soils and slopes. In the same condition of treatments on the field experiment under the natural rainfall, the order of magnitude of influences affecting the rate of surface run-off is the factor of mulchings, soils and slopes. 3. Experiment factors and soil losses The soil losses of the experiment plots differed according to the factors of soil texture, slope steepness, rainfall intensity and mulching method. The soil losses from the coarse soil were increased about 1.1~1.3 times as compared with that of fine soil under the natural rainfall, while the soil losses from the fine soil were increased about 1.2~1.3 times compared with that of coarse soil under the simulated rainfall. The equation of $E=aS^b$ (a, b are constant) between the slope steepness (log S) and soil losses (log E) under the simulated rainfall were developed. The equation of $E=aI^b$ (a, b are constant) between the rainfall intensity (log I) and soil losses (log E) were developed, and b values have a decreasing tendency according to the increase of the slope steepness and rainfall intensity. The soil losses under the natural rainfall were appeared about 38~41% from the coarse straw-mat mulched slopes, about 20~22% from the liquid mulched slopes, about 14~15% from the grass mulched slopes as compared with that of the bare slopes respectively. The soil loss from the vegetation plots showed about 7.1~16.4 times from the sparse plot, about 10.0~17.9 times from the moderate plot and about 11.1~28.1 times from the dense plot as compared with that of the bare slopes. 4. Magnitudes of influences and interactions of the individual factor on the soil erosion. The experimental analyses on the major factors(soils, slopes, rainfalls, mulchings and vegetations) affecting the soil erosion, show that the mean differences of soil losses are highly significant between the soil texture factors, among the slope steepness factors, among the rainfall intensity factors, among the mulching method factors and among the vegetation density factors respectively. The interactions among the individual factor have mostly great influences upon the soil erosion. The magnitude of influences of three factors (soils, slopes and rainfalls) affecting the soil erosion on the bare slopes under the simulated rainfall is in order of the factor of rainfalls, soils and slopes. On the mulched slopes under the simulated rainfall, the magnitude order of influences of three factors(soils, rainfalls and mulchings) affecting the soil erosion is the factor of mulchings, rainfalls and soils, and the order of influences of factor of soils, slopes and mulchings is the factor of mulchings, soils and slopes. On the vegetation growing slopes under the simulated rainfall, the magnitude of influences of three factors (soils, slopes and vegetations) affecting the soil erosion is in the order of the factor of slopes. vegetations and soils. In the same condition of treatments on the field experiment under the natural rainfall, the order of magnitude of influences of three factors (soils, slopes and mulchings) affecting the soil erosion is the factor of mulchings, of slopes and of soils.

• Bulletin of the Korean Chemical Society
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• v.5 no.3
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• pp.121-126
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• 1984

The charge transfer complex formations between indole derivatives and methylviologen were investigated spectroscopically. In aqueous solutions near room temperature, the order of complex stability was tryptamine < tryptophan < indole < indole acetate, which is the reverse order of the magnitude of molar absorptivities. This was interpreted as involvement of contact charge transfer. The decrease of enthalpy of complex formation (-${\Delta}$H) was highest in tryptamine, and lowest in indole acetate. ${\Delta}$H and entropy of complex formation (${Delta}$S) varied nearly in a linear fashion with isokinetic temperature $242^{\circ}$K. These results were attributed to the hydration-dehydration properties of the side chains in indole derivatives. Except indole acetate, the complex formations were greatly enhanced by the addition of sodium dodecyl sulfate(SDS). However, the direct relationship between the enhanced complex formation and SDS micelle formation was not found. The enhanced charge transfer interaction inSDS solutions was attributed to the increased ${\Delta}$S by interaction between methylviologen and SDS in premicellar level. The order of complex stability in SDS solutions was indole acetate < tryptophan < trypamine < indole, which reflects the hydrophobicity of indole derivatives as well as electrostatic interaction between indole derivatives and methylviologen associated with SDS.

• Structural Engineering and Mechanics
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• v.73 no.6
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• pp.667-684
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• 2020

In this article, the static responses of layered magneto-electro-thermo-elastic (METE) plates in thermal environment have been investigated through FE methods. By using Reddy's third order shear deformation theory (TSDT) in association with the Hamilton's principle, the direct and derived quantities of the coupled system have been obtained. The coupled governing equations of METE plates have been derived through condensation technique. Three layered METE plates composed of piezoelectric and piezomagnetic phases are considered for evaluation. For investigating the correctness and accuracy, the results in this article are validated with previous researches. In addition, a special attention has been paid to evaluate the influence of different electro-magnetic boundary conditions and pyrocoupling on the coupled response of METE plates. Finally, the influence of stacking sequences, magnitude of temperature load and aspect ratio on the coupled static response of METE plates are investigated in detail.

• Korean Institute of Interior Design Journal
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• v.13 no.3
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• pp.43-51
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• 2004

1"his Study is to make research a Image and Symbol in the Gothic Architecture. Firstly, the concept of the symbol and the image effect are essentially based on the meaning that the activity of consciousness take on the constitution of the symbol. Therefore the image represent the deepest content of human nature has been imagination and reality. Secondly, the symbol concept showed in Gothic Architecture was associated with the passion of the order of middle ages. The world, the cosmos and the history had been revealed in Gothic architecture. In Gothic Image, Emile Male maintained the symbol of the Catholic Church as above mentioned. The Catholic Church was mirror of the natural, the institution, the moral and history, then this passion of the order was a christian order. Especially, E. Panofsky said that the scholastic method was shown in Gothic architecture. He assert that it was especially dialectic method used in theology. That is, he explained the transfiguration of Gothic Architecture with the process of thesis, anti-thesis, synthesis. These symbolize light, magnitude, clearness. Finally, symbolic image is important in Post-Modem architecture at present. Post-Modern architecture is associated with the public and the Pluralism. Post-Modern architecture attempt to communicate as symbolic language among the assumption for diverse aspect of culture.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.2
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• pp.186-193
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• 2008

[ $Moir{\acute{e}}$ ] interferometry is an optical method, providing whole field contour maps of in-plane displacements with high resolution. The demand for enhanced sensitivity in displacement measurements leads to the technique of microscopic $moir{\acute{e}}$ interferometry. The method is an extension of the $moir{\acute{e}}$ interferometry, and employs an optical microscope for the required spatial resolution. In this paper, the sensitivity of $moir{\acute{e}}$ interferometry is enhanced by an order of magnitude using an immersion interferometry and the optical/digital fringe multiplication(O/DFM) method. In fringe patterns, the contour interval represents the displacement of 52 nm per fringe order. In order to estimate the reliability and the applicability of the optical system implemented, the measurements of rigid body displacements of grating mold and the coefficient of thermal expansion(CTE) for an aluminium block are performed. The system developed is applied to the measurement of thermal deformation in a flip chip plastic ball grid array package.

• Journal of the Korean Society for Advanced Composite Structures
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• v.1 no.1
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• pp.1-8
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• 2010

The dynamic instability analysis of delaminated composite structures subjected to in-plane pulsating forces is carried out based on the higher order shell theory of Sanders. In the finite element (FE) formulation, the seven degrees of freedom per each node are used with transformations in order to fit the displacement continuity conditions at the delamination region. The boundaries of the instability regions are determined using the method proposed by Bolotin. The numerical results obtained for skew plates and shells are in good agreement with those reported by other investigators. The new results for delaminated skew plate and shell structures in this study mainly show the effect of the interactions between the radius-length ratio and other various parameters, for example, skew angles, delamination size, the fiber angle of layer and location of delamination in the layer direction. The effect of the magnitude of the periodic in-plane load on the instability regions is also investigated.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1784-1787
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• 2002

Two-dimensional (2-D) digital filters are widely useful inn image processing and other 2-D digital signal processing fields, but designing 2-D filters is much more difficult than designing one-dimensional (1-D) ones. This paper provides a new insight into the existing singular value decomposition (SVD)-based design approach in the sense that the SVD-based design can be performed more efficiently by exploiting the symmetries of the given 2-D magnitude specifications. By using the specification symmetries. only half of the 1-D filters (sub-filters) need to be designed. which significantly simplifies the design process and reduces the computer storage required for 1-D sub-filter coefficients. Another novel point of this paper si that an objective criterion is proposed for selecting appropriate sub-filter orders in order to reduce the hardware implementation cost. A design example is given to illustrate the effectiveness of the SVD-based design approach by exploiting specification symmetry and new order-selecting criterion.

• Bulletin of the Korean Chemical Society
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• v.22 no.7
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• pp.669-672
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• 2001

Pseudo-first-order rate constants have been measured spectrophotometrically for the title reactions. The plot of kobs vs the concentration of alkali metal ethoxides is linear for the reactions performed in the presence of complexing age nt, 18-crown-6 ether, but curved upwardly for the corresponding reactions performed in the absence of the complexing agent, indicating that the alkali metal ions studied in this study behave as a catalyst. The catalytic effect was found to increase in the order Li+ << K+ ${\leq}$ Na+. Second-order rate constants were determined for the reactions with dissociated free ethoxide (kEtO-) and with ion paired alkali metal ethoxides (kEtO-M+ ) from ion pairing treatments. The magnitude of catalytic effect (kEtO-M+/kEtO-) was found to be 2.3, 9.5 and 8.7 for the reaction of 8-(5-nitroquinolyl) 2-furoate, while 1.4, 3.6 and 4.2 for that of 4-nitrophenyl 2-furoate, indicating that the catalytic effect is larger in the reaction of the former substrate than in that of the latter one. The larger catalytic effect was attributed to two possible complexing sites with alkali metal ions in the former substrate.

• Nuclear Engineering and Technology
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• v.32 no.4
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• pp.350-360
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• 2000

In Korea, the dose limits are reduced and are set at the ICRP-60 iimits. However, derived limits tabulated as MPC in air and water are still specified in Notice No.98-12. There are some discrepancies between the primary dose limits and MPCs in air and water. Therefore, in order to accept ICRP-60 recommendations fully, derived limits such as ALI, DAC, ECL for radiological protection against ionizing radiation based on ICRP-60 recommendations were calculated using modified methods of those of 10 CFR part 20, dose limits and committed effective dose coefficients of the Basic Safety Standards of the IAEA. The derived limits in this study were also compared with those prescribed in 10 CFR part 20 as well as MPCs of Notice No. 98-12 in order to analyze the impact of implementing derived limits on nuclear facilities. ECLs in air and water for the control of radioactive discharge into the environment in this study are shown to have lower values (i.e. more conservative), for most part, than those in Notice No. 98-12. Especially, for uranium elements, ECLs in water are approximately a magnitude in the order of two lower than those in Notice No.98-12.

• The Transactions of the Korean Institute of Electrical Engineers B
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• v.49 no.7
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• pp.500-508
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• 2000

Basic design for single-phase active power filter, which aims at railway application provided with PWM-controlled converters, is comprehensively studied and its performance is presented in this paper. Active power filters are used to compensate railway signaling and public telecommunication interference due to the high-order harmonic currents generated in railway traction locomotives. A type of hybrid digital filter which is composed of low pass filter and high pass filter is proposed so that the desired harmonic reference current with accurate magnitude and phase shift can be extracted from catenary line current. A design criteria to determine input inductor L and output capacitor C is also described, considering voltage, current, PWM pattern, and switching frequency of the main converters. Finally, computer simulation and DSP-based experiments resulted from laboratory test are presented.