• Journal of the Computational Structural Engineering Institute of Korea
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• v.25 no.6
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• pp.533-540
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• 2012

Rubber laminated bearings with lead core are highly affected by changes in temperature because key materials which are rubber and lead have temperature dependencies. In this study, two full scale LRB(D800, S=5) are manufactured and temperature dependency tests on shear properties are accomplished. The shear properties at the 3rd cycle are used at $-10^{\circ}C$, $0^{\circ}C$, $10^{\circ}C$, $20^{\circ}C$, $30^{\circ}C$, $40^{\circ}C$ respectively. The double shear configuration, simultaneously testing two pieces, is applied for compression shear test in order to minimize the friction effects due to the test machine, described in ISO 22762-1:2010. Characteristic strength, post-yield stiffness, effective stiffness, equivalent damping ratio are estimated and presented coefficient due to the temperature changes.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.6
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• pp.440-447
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• 2020

Masonry structures are used as bearing walls in small buildings, but they are generally considered non-bearing walls. They are used as partition walls that divide the interior spaces of the frame structures of buildings. In addition, wetting techniques that use mortar as an adhesive between blocks or bricks in construction are vulnerable to climatic conditions, especially cracks in mortar, which can cause conduction collapse of the walls in seismic loading. The purpose of this research was to propose a dry concrete block construction method that complements the weak axial shear stiffness and improves the weakness of the wet construction method as well as to investigate its structural behavior. In this study, the material properties of concrete blocks were examined, and the seismic performance of the proposed dry assembly structure was verified by structural behavior tests on horizontal cyclic loads. First, in these study results, concrete blocks can be applied to the dry block construction method instead of wet construction methods because they secure more than C-type blocks in KS regulations. Second, the structural performance of the wall against a horizontal cyclic load indicates that the resisting force of the assembly block wall is increased by increasing the horizontal length of the wall, forming several diagonal cracks. Finally, the proposed dry block wall structure requires a seismic performance assessment considering that the ratio of the shape of the wall by height and length is considered a major influence variable on the structural behavior under a horizontal load.

• Nutrition Research and Practice
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• v.9 no.2
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• pp.129-136
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• 2015

BACKGROUND/OBJECTIVES: A variety of immunomodulators can improve the efficacy of low-dose chemotherapeutics. Active hexose correlated compound (AHCC), a mushroom mycelia extract, has been shown to be a strong immunomodulator. Whether AHCC could enhance the antitumor effect of low-dose 5-fluorouracil (5-FU) via regulation of host immunity is unknown. MATERIALS/METHODS: In the current study Hepatoma 22 (H22) tumor-bearing mice were treated with PBS, 5-FU ($10mg{\cdot}kg^{-1}{\cdot}d^{-1}$, i.p), or AHCC ($360mg{\cdot}kg^{-1}{\cdot}d^{-1}$, i.g) plus 5-FU, respectively, for 5 d. $CD^{3+}$, $CD^{4+}$, $CD^{8+}$, and NK in peripheral blood were detected by flow cytometry. ALT, AST, BUN, and Cr levels were measured by biochemical assay. IL-2 and $TNF{\alpha}$ in serum were measured using the RIA kit and apoptosis of tumor was detected by TUNEL staining. Bax, Bcl-2, and TS protein levels were measured by immunohistochemical staining and mRNA level was evaluated by RT-PCR. RESULTS: Diet consumption and body weight showed that AHCC had no apparent toxicity. AHCC could reverse liver injury and myelosuppression induced by 5-FU (P < 0.05). Compared to mice treated with 5-FU, mice treated with AHCC plus 5-FU had higher thymus index, percentages of $CD^{3+}$, $CD^{4+}$, and NK cells (P < 0.01), and ratio of $CD^{4+}$/$CD^{8+}$ (P < 0.01) in peripheral blood. Radioimmunoassay showed that mice treated with AHCC plus 5-FU had the highest serum levels of IL-2 and $TNF{\alpha}$ compared with the vehicle group and 5-FU group. More importantly, the combination of AHCC and 5-FU produced a more potent antitumor effect (P < 0.05) and caused more severe apoptosis in tumor tissue (P < 0.05) compared with the 5-FU group. In addition, the combination of AHCC and 5-FU further up-regulated the expression of Bcl-2 associated X protein (Bax) (P < 0.01), while it down-regulated the expression of B cell lymphoma 2 (Bcl-2) (P < 0.01). CONCLUSIONS: These results support the claim that AHCC might be beneficial for cancer patients receiving chemotherapy.

• YAKHAK HOEJI
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• v.48 no.6
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• pp.335-344
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• 2004

Interleukin-2 (IL-2), a glycoprotein mainly secreted by CD4+ T helper Iymphocytes, has been developed to use recombinant cytokine to augment the immune response against cancer since IL-2 not only stimulates T Iymphocytes but also enhances natural killer (NK) cell activity. In order to evaluate the immunological safety of recombinant mouse IL-2 (rmIL-2) in cancer therapy, renal cell carcinoma was established in the flank by s.c. injection of renca cell line. Tumor-bearing BALB/c mice were treated with I.p. injections with $2{\times}10^5$ Lu rmIL-2. Even though the tumor size was diminished, there were not significant recovery of body and relative lymphoid organ weights including thymic atrophy in rmIL-2 immunotherapy. Distribution ratios of T cell subsets in thymus were analysed using flow cytometry. Without regard to dosage of rmIL-2, the ratio of CD3+CD4-CD8- T cells was increased in accordance with survival of solid tumor but that of CD4+CD8+ T cells was decreased dramatically. Emergence of autoantibodies (ANA, anti-dsDNA, and anti-histone) in blood was measured after rmIL-2 treatment. The results showed that the levels of ANA and anti-dsDNA did not significantly changed, but the level of anti-histone was increased significantly owing to rmIL-2 therapy. These results indicate rmIL-2 immunotherapy is to induce the autoimmune potential, and the anti-histone measurement as a biomarker of autoimmunity is useful in cancer immunotherapy.

• Korean journal of applied entomology
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• v.48 no.4
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• pp.485-491
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• 2009

This study was conducted to investigate the fruit damage according to the number of released stink bugs and date of adult introduced on non-astringent persimmon. The fruit damage differed significantly by the number, date, and the source of feed for Riptortus clavatus. Damages on the fruits appeared when five bugs were released to mother branches bearing fruits. Damages to the fruits was heavy in the case that bugs were introduced in September and October, compared with in June, July and August. Persimmon fruit damage was influenced significantly by the available sources to R. clavatus, persimmon fruit alone or additional supply of kidney bean (Phaseolus vulgaris) and water. Characteristic damage symptoms by R. clavatus showed only scars on the fruit skin, without fruit dropping. Halyomorpha halys (=mista) showed significantly higher fruit damage when they were released in July, August, and September compared with other periods. Number of H. halys to the fruit also showed significant differences in fruit damages. Five H. halys in July showed 100% damaged fruits. The fruit damage by Plautia stali was not significantly different according to dates of introduction but the number of insects gave significant differences in the fruit damage ratio at the level of 1, 3, 5 bugs introduced to the mother branche bearing friuts. The damage symptoms by P. stali was fruit dropping in July and August but from September damaged fruits were found in the branches.

• Economic and Environmental Geology
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• v.21 no.2
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• pp.149-164
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• 1988

Electrum-sulfide mineralization of the Samgwang and Sobo mines of the Cheongyang Au-Ag area was deposited in two stages of quartz and calcite veins that fill fault zones in granite gneiss. Radiometric dating indicates that mineralization is Early Cretaceous age (127 Ma). Fluid inclusion and sulfur isotope data show that ore mineralization was deposited at temperatures between $340^{\circ}$ and $180^{\circ}C$ from fluids with salinities of 1 to 8 wt. % equiv. NaCl and a ${\delta}^{34}S_{{\sum}S}$ value of 2 to 5 per mil. Evidence of fluid boiling (and $CO_2$ effervescence) indicates a range of pressures from < 200 to $\approx$ 700 bars, corresponding to depths of ${\approx}1.5{\pm}0.3\;km$ in a hydrothermal system which alternated from lithostatic toward hydrostatic conditions. Au-Ag deposition was likely a result of boiling coupled with cooling. Meaured and calculated hydrogen and oxygen isotope values of ore-forming fluids indicate a significant meteoric water component, approaching unexchanged paleometeoric water values. Comparison of these values with those of other Korean Au-Ag deposits reveals a relationship among depth, Au/Ag ratio and degree of water-rock interaction. All investigated Korean Jurassic and Cretaceous gold-silver-bearing deposits have fluids which are dominantly evolved meteoric waters, but only deeper systems (${\geq}1.5\;km$) are exclusively gold-rich.

• Journal of the Korean Geotechnical Society
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• v.28 no.8
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• pp.43-53
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• 2012

In the conventional design of a piled raft, the axial resistance offered by the raft itself is typically neglected and only that of the group pile is accounted in estimating the total axial resistance of the piled raft. As a consequence, piled rafts are usually designed conservatively by neglecting the raft resistance. In this study, a series of centrifuge model tests have been performed to compare the axial behavior of a group pile with that of a piled raft (both having 16 component piles with an array of $4{\times}4$) in sands with different relative densities and in clays with different preconsolidated pressures. The test results revealed that, with respect to the allowable settlement of 25 millimeters for bridge foundations, the piled raft resistances were greater than those of the group pile by 13% for dense sand, by 22% for loose sand, by 30% for stiff clay, and by 22% for soft clay. Furthermore, the ratio of piled raft resistance to group pile resistance increased as the settlement increased.

• Journal of the Korean Solar Energy Society
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• v.35 no.2
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• pp.73-83
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• 2015

When it comes to these buildings for business use, cooling load during summertime was reported to have great importance which, as a result, impressively increased interest in Solar Heat Gain Coefficient (SHGC). Such SHGC is considered to be lowered with the help of colors and functions of glass itself, internal shading devices, insulation films and others but basically, these external shading devices for initial blocking that would not allow solar heat to come in from outside the buildings are determined to be most effective. Of many different external shading devices, this thesis conducted an analysis on Exterior Venetian Blind. As for vertical shading devices, previous researches already calculated SHGC conveniently using concepts of sky-opening ratios. However in terms of the Venetian Blind, such correlation is not possibly applied. In light of that, in order to extract a valid correlation, this study first introduced a concept called shape factor, which would use the breadth and a space of a shade, before carrying out the analysis. As a consequence, the concept helped this study to find a very similar correlation. Results of the analysis are summarized as follows. (1) Regarding SHGC depending on the surface reflectance of a shade, an average of 2% error is observed and yet, the figure can always be ignored when it comes to a simple calculation. (2) As for SHGC of each bearing, this study noticed deviations of 4% or less and in the end, it is confirmed that extraction can be achieved with no more than one correlation formula. (3) When only the shape factor and nothing else is used for finding a correlation formula, the formula with a deviation of approximately 5% or less is what one would expect. (4) Since the study observed slight differences in bearings depending on ranges of the shape factors, it needed to extract a weighted value of each bearing, and learned that the smaller the shape factor, the wider the range of a weighted value. The study now suggests that a follow-up research to extract a simple calculation formula by dealing with all these various inclined angles of shade, solar radiation conditions of each region (the ratio of diffuse radiation to direct radiation and others) as well as seasonal features should be carried out.

• Journal of the Korean Geotechnical Society
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• v.28 no.9
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• pp.5-15
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• 2012

Field monitoring data for embankments in thirteen road construction sites at coastal area of the Korean Peninsula were analyzed to investigate the characteristics of lateral flow in soft grounds, to which vertical drain methods were applied. First of all, the effect of the embankment scale on the lateral flow was investigated. Thicker soft soils and lager relative embankment scale produced more horizontal displacements in soft grounds. Especially, if thick soft grounds were placed, the relative embankment scale, which was given by the ratio of thickness of soft ground to the bottom width of embankments, became larger and in turn large horizontal displacement was produced. And also higher filling velocity of embankments induced more horizontal displacements in soft grounds. The other major factors affecting the lateral flow in soft ground were the thickness and undrained shear strength of soft grounds, the soil modulus and the stability number. Maximum horizontal displacement was induced by less undrained shear strength and soil modulus of soft grounds. Also more stability numbers produced more maximum horizontal displacements. When the shear deformation does not develop, the stability number was less than 3.0 and the safety factor of bearing was more than 1.7. However, if the stability number was more than 5.14 and the safety factor of bearing was less than 1.0, the unstable shear failure developed in soft ground. 50mm can be recommended as a criterion of the allowable maximum horizontal displacement to prevent the shear deformation in soft ground, while 100mm can be recommended as a criterion of the allowable maximum horizontal displacement to prevent the shear failure in soft ground.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.154-162
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• 1992

This study was designed to investigate the antitumor effect and immunological activities of chitosan extracted from Solenocera prominetis toward on mire bearing sarcoma-180. The growth inhibition ratio of the chitosan toward sarcoma-180 showed at the highest level of 63.84% when chitosan were administrated at the concentration of 40mg/kg. The direct cytotoxic effect of chitosan was not observed in the mice bearing sar-roma-180 in vitro. In the effect of immunological activities, dose-dependent responses indicated by the increase of leucocyte, peritoneal exudate cell than that of control group when chitosan administered to the mice in the concentation of 30mg/kg and 40mg/kg. Also dose-dependent responses showed also by the increase of immunoorgans weights such as body weight, liver, spleen or thymus in the same concentration of 30mg/kg and 40mg/kg. Food pad swelling having the relationship with arthus reaction of antibody-mediated hypersensitivity and delayed type hypersensitivity was recovered the almost normal level. In the efforts of macrophge on phagocytes, there were not substantial differences in phagorytic and corrected phagocytic index. In the number of plaque forming cell(PFC), PFC on the 10$^{7}$ spleen cells were increased the levels of 18.88% and 31.83% when chitosan were adminstersd at the concentration of 30mg/kg and 40mg/kg.