• Progress in Superconductivity
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• v.8 no.2
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• pp.175-180
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• 2007

High temperature superconductor $YBa_2Cu_3O_{7-x}$ (YBCO) films have been grown by in-situ electron beam evaporation on artificial metal tapes such as ion-beam assisted deposition (IBAD) and rolling assisted biaxially textured substrates (RABiTS). Deposition rate of the YBCO films is $10{\sim}100{\AA}/sec$. X-ray diffraction shows that the films are grown epitaxially but have inter-diffusion phases, like as $BaZrO_3\;or\;BaCeO_3$, at their interfaces between YBCO and yttrium-stabilized zirconia (YSZ) or $CeO_2$, respectively. Secondary ion mass spectroscopy depth profile of the films confirms diffused region between YBCO and the buffer layers, indicating that the growth temperature ($850{\sim}900^{\circ}C$) is high enough to cause diffusion of Zr and Ba. The films on both the substrates show four-fold symmetry of in-plane alignment but their width in the -scan is around $12{\sim}15^{\circ}$. Transmission electron microscopy shows an interesting interface layer of epitaxial CuO between YBCO and YSZ, of which growth origin may be related to liquid flukes of Ba-Cu-O. Resistivity vs temperature curves of the films on both substrates were measured. Resistivity at room temperature is between 300 and 500 cm, the extrapolated value of resistivity at 0 K is nearly zero, and superconducting transition temperature is $85{\sim}90K$. However, critical current density of the films is very low, ${\sim}10^3A/cm^2$. Cracking of the grains and high-growth-temperature induced reaction between YBCO and buffer layers are possible reasons for this low critical current density.

• The Journal of Engineering Geology
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• v.3 no.3
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• pp.215-230
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• 1993

In-situ rock mass demonstrates the variety of structural features, and especially the mechanical and spatial characteristics of joint (or joint system) greatly affect the deformation and fallure strength of the rock mass. In this study finite element model capable of analyzing the viscoplastic behavior of reinforced jointed rock mass has been developed based on equivalent material approach. Accuracy and reliability of the numerical model have verified by simuiating the behavior of simplified block model and comparing the results with analytic solutions. Practical applicability was also demonstrated by analyzing the time-dependent behavior of underground oil storage tunnel and assessing the reinforcement effect of rockbolt.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2673-2678
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• 2016

Background: It is unclear as to whether the size ratio elastographic technique is useful for assessing ultrasound-detected ductal carcinoma-in-situ (DCIS) masses since they commonly lack a significant desmoplastic reaction. The objectives of this study were to determine the accuracy of this elastographic technique in DCIS and examine if there was any histopathological correlation with the grey-scale strain patterns. Materials and Methods: Female patients referred to the radiology department for image-guided breast biopsy were prospectively evaluated by ultrasound elastography prior to biopsy. Histological diagnosis was the gold standard. An elastographic size ratio of more than 1.1 was considered malignant. Elastographic strain patterns were assessed for correlation with the DCIS histological architectural patterns and nuclear grade. Results: There were 30 DCIS cases. Elastographic sensitivity for detection of malignancy was 86.7% (26/30). 10/30 (33.3%) DCIS masses demonstrated predominantly white elastographic strain patterns while 20/30 (66.7%) were predominantly black. There were 3 (10.0%) DCIS masses that showed had a co-existent bull's-eye sign and 7 (23.3%) other masses had a co-existent toothpaste sign, a strain pattern that has never been reported in the literature. Four out of 4/5 comedo DCIS showed a predominantly white strain pattern (p=0.031) while 6/7 cases with the toothpaste sign were papillary DCIS (p=0.031). There was no relationship between the strain pattern and the DCIS nuclear grade. Conclusions: The size ratio elastographic technique was found to be very sensitive for ultrasound-detected DCIS masses. While the elastographic grey-scale strain pattern should not be used for diagnostic purposes, it correlated well with the DCIS architecture.

• The Korean Journal of Physiology and Pharmacology
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• v.14 no.2
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• pp.71-75
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• 2010

To investigate the intestinal absorption of a fibrinolytic and proteolytic lumbrokinase extracted from Eisenia andrei, we used rat everted gut sacs and an in situ closed-loop recirculation method. We extracted lumbrokinase from Eisenia andrei, and then raised polyclonal antibody against lumbrokinase. Fibrinolytic activity and proteolytic activity in the serosal side of rat everted gut sacs incubated with lumbrokinase showed dose- and time-dependent patterns. Immunological results obtained by western blotting serosal side solution using rat everted gut sacs method showed that lumbrokinase proteins between 33.6 and 54.7 kDa are absorbed mostly by the intestinal epithelium. Furthermore, MALDI- TOF mass spectrometric analysis of plasma fractions obtained by in situ recirculation method confirmed that lumbrokinase F1 is absorbed into blood. These results support the notion that lumbrokinase can be absorbed from mucosal lumen into blood by oral administration.

• Journal of Plant Biotechnology
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• v.47 no.4
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• pp.330-336
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• 2020

Ex-situ conservation of the ornamental and medicinal orchid, Coelogyne stricta, was performed by mass propagation using seed culture. Propagation stages were optimized using full- and half-strength solidified MS medium with different phytohormones. Maximum seed germination (88 ± 0.5% over 6 weeks of culture) was achieved on half-strength MS medium supplemented with 15% coconut water. Maximum shoot numbers were found on full-strength MS medium supplemented with 1 mg/L BAP, 2 mg/L Kinetin, and 10% coconut water, while the longest root was developed on full-strength MS medium with 1.5 mg/L IBA. A 2:1:1 combination of coco-peat, pine bark, and sphagnum moss was found to be a suitable potting mixture resulting in 80% seedling survivability. The cytotoxic activity of extracts of both wild plants and in vitro-developed protocorms was determined using an MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) assay on a cervical cancer cell line. The wild plant extract inhibited the growth of 41.99% of cells, showing that this extract has moderate cytotoxic activity toward cervical cancer cells.

• Tunnel and Underground Space
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• v.21 no.2
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• pp.117-127
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• 2011

The purpose of this study is to demonstrate the effect of in-situ rock stresses on the deformability and permeability of fractured rocks. Geological data were taken from the site investigation at Forsmark, Sweden, conducted by Swedish Nuclear Fuel and Waste Man-agement Company (SKB). A set of numerical experiments was conducted to determine the equivalent mechanical properties (essentially, elastic moduli and Poisson's ratio) and permeability, using a Discrete Fracture Network-Discrete Element Method (DFN-DEM) approach. The results show that both mechanical properties and permeability are highly dependent on stress because of the hyperbolic nature of the stiffness of fractures, different closure behavior of fractures, and change of fluid pathways caused by deformation. This study shows that proper characterization and consideration of in-situ stress are important not only for boundary conditions of a selected site but also for the understanding of the mechanical and hydraulic behavior of fractured rocks.

• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.3
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• pp.87-93
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• 2008

The large scale shaker can be employed to measure linear and nonlinear shear moduli of soils in situ as a function of shear strain. The method involves applying dynamic loads on a surface foundation measuring the dynamic response of the soil mass beneath the foundation with embedded instrumentation. This paper focuses on the development of a framework of the inverse analysis for the interpretation of test data to estimate linear and nonlinear shear moduli of soils along with the necessity of the inverse analysis. The suggested framework is based on the nonlinear least squares but it uses two iterative loops to account for the nonlinear behavior of soil that sensors are not located. The validity of the suggested inversion framework is tested through a series of numerical parametric studies. An example use of the suggested inversion framework is also shown. Because the field condition may affect the accuracy of suggested method, it is important to conduct a preliminary inverse analysis to quantify the discrepancy between the estimated modulus and the baseline.

• Tunnel and Underground Space
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• v.12 no.3
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• pp.220-228
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• 2002

Thermal flow through jointed rock mass was analyzed by numerical methods. The effect of a single set of joints on the heat conduction was analyzed by one-dimensional model and compared with the analytical solution. When a joint is completely dry, the joint behaves as a thermal break inducing jumps in temperature distribution even at steady state. Therefore when joints are completely dry, individual joint has to be taken into consideration to get a good result. When joints are partially or fully saturated, the thermal conductivity of the joints increases drastically and the jumps in temperature distribution become less severe. Therefore the effect of joint in heat conduction can be well absorbed by continuum anisotropic model whose thermal properties represent overall thermal properties of the intact part and the discontinuities. Since the effect of joints becomes less important as the degree of the saturation increases, the overall thermal response of the rock mass also becomes close to isotropic. Therefore it can be concluded that a great effort has to be made to obtain a precise in-situ thermal properties in order to get a good prediction of the thermal response of a jointed rock mass.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.543-550
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• 2000

Rock slopes along the road or railroad are affected by temperature and therefore experienced iterative freezing-thawing process between winter and early spring. The purpose of this study is to analyze the stability of rock slopes which are influenced by the deterioration due to the freezing-thawing. The analysis is the homogenization method which evaluates the strength property of discontinuous rock mass, and as a strength failure criterion, Drucker-Prager failure criterion is used. The deterioration property of real rock is obtained by a freezing-thawing laboratory test of tuff and this property of deterioration is quantitated and used as a basic data of stability analysis for rock mass. To evaluate the deterioration depth due to the freezing-thawing in situ rock slope, one dimensional heat conductivity equation is used and as the result I can find that the depth of which is affected by a temperature. After the freezing-thawing depth of model slope is determined, we analyze the pattern of rock mass stength value of rock slope model which excesses the limit of self-load.

• Korean Journal of Environmental Biology
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• v.30 no.4
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• pp.328-338
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• 2012

We investigated seasonal changes in the marine environments and phytoplankton communities in the western part of south coastal waters of Korea during May 2009 and February 2010. In multidimensional scaling analysis of in situ data obtained by shipboard observations, the coastal waters comprised four different water masses: Yellow Sea water mass (YW) of low temperature and salinity, and high suspended solids and nutrient concentrations; south-western coastal water mass (SW) of high salinity and nutrient concentrations; Tsushima Current water mass (TW) of low nutrient concentrations, and high temperature and salinity; and closed bay water mass (CW). The spatial extent of these water masses varied according to seasonal environmental characteristics. In particular, at most study sites, TW expanded during autumn toward coastal waters. Phytoplankton abundances peaked during autumn in CW and spring in YW, which coincided with periods of high nutrient concentrations. In particular, diatoms predominated, and attained an abundance of more than 90% in most water masses. However, dinoflagellates in TW comprised a proportion of approximately 20% abundance.