• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.2
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• pp.135-143
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• 2004

An experimental study on the sorption of U(VI) onto a Korean granite was performed as a function of the geochemical parameters such as contact time, pH, ionic strength, and carbonate concentration using a batch procedure. The distribution coefficient,$K_d$, was about 1-200 mL/g depending on the experimental conditions. The sorption of U(VI) onto granite particles was greatly dependent upon the contact time, pH, and carbonate concentration, but insignificantly dependent on the ionic strength. It was noticed that the sorption of U(VI) onto granite particles was highly correlated with the uranium speciation in the solution, which was dependent on the pH and carbonate concentrations. It was deduced from the kinetic sorption experiment that a two-step first-order kinetic behavior could dominate the kinetic sorption of U(VI) onto granite particles. In the alkaline range of a pH above 7, U(VI) sorption was greatly decreased and this might be due to the formation of anionic U(VI)-carbonate aqueous complexes as predicted by the speciation calculations.

• Journal of Korean Neurosurgical Society
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• v.55 no.6
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• pp.331-336
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• 2014

Objective : The purpose of this study was to evaluate the differences in sagittal spinopelvic alignment between lumbar degenerative spondylolisthesis (DSPL) and degenerative spinal stenosis (DSS). Methods : Seventy patients with DSPL and 72 patients with DSS who were treated with lumbar interbody fusion surgery were included in this study. The following spinopelvic parameters were measured on whole spine lateral radiographs in a standing position : pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis angle (LL), L4-S1 segmental lumbar angle (SLL), thoracic kyphosis (TK), and sagittal vertical axis from the C7 plumb line (SVA). Two groups were subdivided by SVA value, respectively. Normal SVA subgroup and positive SVA subgroup were divided as SVA value (<50 mm and ${\geq}50mm$). Spinopelvic parameters/PI ratios were assessed and compared between the groups. Results : The PI of DSPL was significantly greater than that of DSS (p=0.000). The SVA of DSPL was significantly greater than that of DSS (p=0.001). In sub-group analysis between the positive (34.3%) and normal SVA (65.7%), there were significant differences in LL/PI and SLL/PI (p<0.05) in the DSPL group. In sub-group analysis between the positive (12.5%) and normal SVA (87.5%), there were significant differences in PT/PI, SS/PI, LL/PI and SLL/PI ratios (p<0.05) in the DSS group. Conclusion : Patients with lumbar degenerative spondylolisthesis have the propensity for sagittal imbalance and higher pelvic incidence compared with those with degenerative spinal stenosis. Sagittal imbalance in patients with DSPL is significantly correlated with the loss of lumbar lordosis, especially loss of segmental lumbar lordosis.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.3
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• pp.1429-1434
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• 2014

Background: Owing to the variability of histopathological features and biological behaviour in gastric carcinoma, a great number of categorisation methods such as classical histopathologic grading, Lauren classification, the TNM staging system and the newly presented Goseki grading method are used by pathologists and other scientists. In our study, we aimed to investigate whether Goseki grade and tumour location have an effects on survival of gastric cancer cases. Materials and Methods: Eighty-four patients with gastric adenocarcinoma were covered in the investigation. The importance of Goseki grading system and tumour location were analysed in addition to the TNM staging and other conventional prognostic parameters. Results: The median survival time in our patients was 35 months (minimum: 5, maximum: 116). According to our findings, there was no relation between survival and tumour size (p=0.192) or classical histological type (p=0.270). In contrast, the Goseki grade and tumour location significantly correlated with survival (p=0.007 and p<0.001, respectively). Additionally, tumours of the intestinal type had a longer median survival time (60.0 months) than diffuse tumours (24.0 months). Conclusions: In addition to the TNM staging system, tumour location and the Goseki grading system may be used as significant prognostic parameters in patients with gastric cancer.

• Journal of Astronomy and Space Sciences
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• v.34 no.2
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• pp.105-110
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• 2017

Solar wind density depletions are phenomena that solar wind density is rapidly decreased and keep the state. They are generally believed to be caused by the interplanetary (IP) shocks. However, there are other cases that are hardly associated with IP shocks. We set up a hypothesis for this phenomenon and analyze this study. We have collected the solar wind parameters such as density, speed and interplanetary magnetic field (IMF) data related to the solar wind density depletion events during the period from 1996 to 2013 that are obtained with the advanced composition explorer (ACE) and the Wind satellite. We also calculate two pressures (magnetic, dynamic) and analyze the relation with density depletion. As a result, we found total 53 events and the most these phenomena's sources caused by IP shock are interplanetary coronal mass ejection (ICME). We also found that solar wind density depletions are scarcely related with IP shock's parameters. The solar wind density is correlated with solar wind dynamic pressure within density depletion. However, the solar wind density has an little anti-correlation with IMF strength during all events of solar wind density depletion, regardless of the presence of IP shocks. Additionally, In 47 events of IP shocks, we find 6 events that show a feature of blast wave. The quantities of IP shocks are weaker than blast wave from the Sun, they are declined in a short time after increasing rapidly. We thus argue that IMF strength or dynamic pressure are an important factor in understanding the nature of solar wind density depletion. Since IMF strength and solar wind speed varies with solar cycle, we will also investigate the characteristics of solar wind density depletion events in different phases of solar cycle as an additional clue to their physical nature.

• Water for future
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• v.27 no.4
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• pp.85-94
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• 1994

A Sensitivity analysis on the model parameters involved in the Clark watershed routing method is made to demonstrate the effect of each parameter on the magnitude of 50-year design flood for small urban streams. As for the rainfall parameter the time distribution pattern of design storm was selected. For short duration storms Huff, Yen & Chow and Japanese Central type distributions were selected and the Mononobe distribution of 24-hour design storm was also selected and tested for Clark method application. The effect of SCS runoff curve number for effective rainfall and the methods of subbasin division for time-area curve were also tested. The routing parameter, i.e. the storage constant(K), was found to be the dominating parameter once design storm is selected. A multiple regression formula for K correlated with the drainage area and main channel slope of the basin is proposed for the use in urban stream practice for the determination of design flood by Clark method.

• Journal of The Korean Astronomical Society
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• v.17 no.2
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• pp.69-103
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• 1984

Five different calibrations of metal abundances of globular clusters are examined and these are compared with metallicity ranking parameters such as $(Sp)_c$, . Q39 and IR-indices. Except for the calibration $[Fe/H]_H$ by the high dispersion echelle analysis. the other calibration scales are correlated with the morphological parameters of red giant branch. In the $[Fe/H]_H$-scale. the clusters later than ${\sim}F8$ have nearly a constant metal abundance. $[Fe/H]_H{\simeq}-1.05$, regradless of morphological characteristics of horizontal branch and red giant branch. By the two fundamental calibration scales of $[Fe/H]_L$ (derived by the low dispersion analysis) and $[Fe/H]_{{\Delta}s}$ (derived by the spectral analysis of RR Lyrae stars). the globular clusters are divided into the halo clusters with [Fe/H]<-1.0 and the disk clusters confined within the galactocentric distance ${\tau}_G=10\;kpc$ and galactic plane distance |z|=3 kpc. In this case the abundance gradient is given by d[Fe/H]/$dr_G{\approx}-0.05\;kpc^{-1}$ and d[Fe/H]/$d|z|{\simeq}-0.08\;kpc^{-1}$ within ${\tau}_G=20\;kpc$ and |z|=10 kpc, respectively. According to these characteristics of the spatial distribution of globular clusters. the chemical evolution of the galactic globular clusters can be accounted for by the two-zone (disk-halo) slow collapse model when the $[Fe/H]_L$-or $[Fe/H]_{{\Delta}s}$-scale is applied. In the case of $[Fe/H]_H$-scale, the one-zone fast collapse model is preferred for the evolution of globular clusters.