• Earthquakes and Structures
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• v.11 no.6
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• pp.1101-1121
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• 2016

Base isolation, one of the popular seismic protection approaches proven to be effective in practical applications, has been widely applied worldwide during the past few decades. As the techniques mature, it has been recognised that, the biggest issue faced in base isolation technique is the challenge of great base displacement demand, which leads to the potential of overturning of the structure, instability and permanent damage of the isolators. Meanwhile, drain, ventilation and regular maintenance at the base isolation level are quite difficult and rather time- and fund- consuming, especially in the highly populated areas. To address these challenges, a number of efforts have been dedicated to propose new isolation systems, including segmental building, additional storey isolation (ASI) and mid-storey isolation system, etc. However, such techniques have their own flaws, among which whipping effect is the most obvious one. Moreover, due to their inherent passive nature, all these techniques, including traditional base isolation system, show incapability to cope with the unpredictable and diverse nature of earthquakes. The solution for the aforementioned challenge is to develop an innovative vibration isolation system to realise variable structural stiffness to maximise the adaptability and controllability of the system. Recently, advances on the development of an adaptive magneto-rheological elastomer (MRE) vibration isolator has enlightened the development of adaptive base isolation systems due to its ability to alter stiffness by changing applied electrical current. In this study, an innovative semi-active storey isolation system inserting such novel MRE isolators between each floor is proposed. The stiffness of each level in the proposed isolation system can thus be changed according to characteristics of the MRE isolators. Non-dominated sorting genetic algorithm type II (NSGA-II) with dynamic crowding distance (DCD) is utilised for the optimisation of the parameters at isolation level in the system. Extensive comparative simulation studies have been conducted using 5-storey benchmark model to evaluate the performance of the proposed isolation system under different earthquake excitations. Simulation results compare the seismic responses of bare building, building with passive controlled MRE base isolation system, building with passive-controlled MRE storey isolation system and building with optimised storey isolation system.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.6
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• pp.835-842
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• 2016

The phosphatidylinositol 3-kinase (PI3K)/Akt signaling pathway plays a crucial role in cancer occurrence by promoting cell proliferation and inhibiting apoptosis. In the present study, we evaluated the effect of a PI3K inhibitor, LY294002, on the chemosensitivity of gastric cancer cells to cordycepin, a predominant functional component of the fungus Cordyceps militaris, in AGS human gastric cancer cells and investigated possible underlying cellular mechanisms. Our results revealed that cordycepin inhibited viability of AGS cells in a concentration-dependent manner and induced apoptosis, as determined by apoptotic cell morphologies and fluorescence-activated cell sorting analysis associated with attenuated activation of the PI3K/Akt signaling pathway. Treatment with cordycepin in combination with a subtoxic concentration of LY294002 enhanced cordycepin-induced cytotoxicity and apoptotic potentials in AGS cells. Sensitization of LY294002 to cordycepin-induced apoptosis was accompanied by activation of caspases (caspases-3, -8, and -9) and was concomitant with poly(ADP-ribose) polymerase cleavage. Moreover, LY294002 up-regulated pro-apoptotic Bax and enhanced truncation of Bid in cordycepin-treated AGS cells, which was connected with increased loss of mitochondrial membrane potential and release of cytochrome c from mitochondria to the cytosol. Taken together, these results indicate that inhibition of the PI3K/Akt signaling pathway could augment cordycepin-induced apoptosis in human gastric cancer cells by up-regulating caspase activity through mitochondrial dysfunction.

• Journal of Sensor Science and Technology
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• v.8 no.4
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• pp.341-346
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• 1999

In general cases, compared with glass electrode, FET type electrolyte sensors have many advantages. But the drift, memory effect and the poor reproducibility of the FET type electrolyte sensor cause the decrease of the reliability in the measurement system. To improve the reliability, an ion-measuring system using FET type electrolyte sensor array with 8 sensors has been developed. Developed system employed the electronic switchs to connect a signal detecting circuit with 8 sensor array and the system can measure ion concentration of 4 different type electrolyte($H^+$, $Na^+$, $K^+$, $Ca^{2+}$). The signal processing algorithm with insertion sorting method was adopted to enhance the reliability. We measured 3 different ion($H^+$, $Na^+$, $K^+$) to evaluate the performance of developed system. The results show that the designed signal processing algorithm can reduce the error range in comparison with a simple arithmetic mean and the developed system has a good reliability over the previous single channel sensor system.

• Lingua Humanitatis
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• v.1 no.1
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• pp.141-157
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• 2001

In his discussion of some desirable tuning points in comparative literary studies, Henry H. H. Remark has emphasized the importance of literary approach to other forms of art. Understanding the significance of such a method of comparative literature, the present study focusses on three contemporary Korean poets who have transferred Mark Chagall′s paintings into their poetry: Youngtae Kim, Chunsoo Kim, and Sunghun Lee. They are usually evaluated as surrealist/modernist in our literary circles. In transforming Chagall′s paintings into his poems, Youngtae Kim has incorporated a variety of surrealist mosaic techniques such as montage and collage. The resultant peculiarity of his poetry makes it hard to lay bare the correspondence or similarities between his poetic world and the world of Chagall′s artistry. It is nonetheless possible to see how Kim, as a poet and painter, had interpreted Chagall′s world with a bird′s-eye view of it. Chunsoo Kim′s "Snow Falling on the Village of Chagall" relates specially to one of Chagall′s paintings, "I and My Village." The present study has taken notice of this correlation in sorting out some basic elements of poetic transfiguration. One of the techniques employed in the poem under discussion is that of juxtaposing the Russian village of Chagall and the Korean village the poet visualizes, with the effect of putting two national traditions in contrast. A reading of the poem reveals that it is not so much the result of a detailed analysis of the painting as a revival of its lingering impression as a whole. In Sunghun Lee′s poetry, surrealist techniques are again a hallmark. But his method of transferring the images of the paintings into his poems falls somewhere between those of Youngtae Kim′s and Chunsoo Kim′s: it is akin to the ′bird′s-eye method′ of the former and shares the impressionistic touch with the latter, but at the same time Lee is analytical by disposition and opts for concrete descriptions. ′Love,′ ′farm,′ and ′time′ are the keywords that are brought under discussion in the present study. There is a growing demand in the current international comparative literary studies for broadening the area of comparative literature. This study hopes to be a small contribution to endorsing the importance of comparative approach to fine arts.

• Korean Journal of Poultry Science
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• v.43 no.4
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• pp.263-272
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• 2016

In this study, we aimed to identify the nonsynonymous single nucleotide polymorphisms (nsSNPs) located in lipid metabolism-related genes because lipids are an important factor affecting the taste and flavor of meat, and they predict the functional consequences. The results showed that we identified 139 common nsSNPs in all five Korean native chicken (KNC) lines from the 81 genes related to lipid metabolism. Furthermore, sorting intolerant from tolerant (SIFT) and polymorphism phenotyping v2 (Polyphen-2) analyses predicted that among the genes, 14 nsSNPs of nine genes might be deleterious. Protein domain prediction of the nine genes revealed that all deleterious nsSNPs identified in this study were located outside the functional domain. This observation suggests that the common deleterious nsSNPs might be dispensable and have a minor effect on the traits of the KNCs.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.1
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• pp.49-54
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• 2003

This study was conducted to evaluate characteristics of particle composition and organic matter distribution for tidal flat sediments in the Saemankeum area. The tidal flat sediments consist of predominantly sand and a little of silt, whereas the content of clay was very low. The analyzed values of particles of tidal flat sediments were in the range of $4.60\~10.90\;{\phi}$ for mean size and $-0.1\~1.75\;{\phi}$ for sorting and $-1.0\~0.92\;{\phi}$ for skewness and $0.27\~6.75\;{\phi}$ for kurtosis. The tidal flat sediments are interpreted as representing significant effect of the environmental change due to the construction of Saemankeum embankment. The ORP was in the range of -133$\~$200 (mean 73) mV. But 24 stations of the total stations showed reduction condition, The concentration of CODs was in the range of 17.54$\~$6,176.3 mg/kg. The ratio of C/S was 0.02$\~$0.45 (mean 0.24). And the Saemankeum tidal flat sediment was a little effected by input organic pollutants from upper site area. Conclusively, conservation of the Saemankeum tidal flat sediment was requested because it is for the growing fishery and low organic matter.

• The Korea Journal of Herbology
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• v.33 no.5
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• pp.47-52
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• 2018

Objectives : The purpose of this study is to investigate effects on the immune system of Bombyx mori L. and Liriopis seu Ophiopogonis Tuber mixture (BL) in Thymus, Lymph Nodes. Methods : Eight-week-old male Balb/c mice were divided into five groups : Group one included the normal mice (Nor). Positive control group two administrated with red ginseng (RG) 100 mg/kg. Group three administrated with Bombyx mori L. (BX) 300 mg/kg. Group four administrated with Liriopis seu Ophiopogonis Tuber (LP) 300 mg/kg. Group five administrated with the mixture of Bombyx mori L. and Liriopis seu Ophiopogonis Tuber (BL) 300 mg/kg. After 2 weeks administration, mice were sacrified and antigen receptor in Thymus, Lymph Nodes was analyzed by using Fluorescence Activated Cellorter Sorting (FACS). we counted the total of Thymus and Lymph Nodes cells. GOT (glutamlc oxaloacetic transaminase), GPT (glutamlc pyruvic transamlnase) in serum were analyzed after experiment. Results : In Effects of Nor, RG, BX, LP, BL on the ratio of CD4+CD8+, CD4+CD69+ and CD4+CD25+ T cell in Thymus and Lymphnode, BL is higher than other groups except Nor in CD4+, CD4+CD69+, CD4+CD25+ T cell. The number of Thymus and Lymph Nodes increased in BL. In the level of GOT and GPT, BL decreased comparing to others group except Nor. Conclusions : BL may have effect on T cells in Thymus, Lymph Nodes. In addition, Bombyx mori could be immune functional material with others herb materials.

• Proceedings of the Korean Society of Medical Physics Conference
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• 2003.09a
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• pp.44-44
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• 2003

As a basic measurement tool in the areas of animal models of human disease, gene expression and therapy, and drug discovery and development, small animal PET imaging is being used increasingly. An ideal small animal PET should have high sensitivity and high and uniform resolution across the field of view to achieve high image quality. However, the combination of long narrow pixellated crystal array and small ring diameter of small animal PET leads to the degradation of spatial resolution for the source located at off center. This degradation of resolution can be improved by determining the depth of interaction (DOI) in the crystal and by taking into account the information in sorting the coincident events. Among a number of 001 identification schemes, dual layer phsowich detector has been widely investigated by many research groups due to its practicability and effectiveness on extracting DOI information. However, the effects of each crystal length composing dual layer phoswich detector on DOI measurements and image qualities were not fully characterized. In order to minimize the DOI effect, the length of each layer of phoswich detector should be optimized. The aim of this study was to perform simulations using a simulation tool, GATE to design the optimum lengths of crystals composing a dual layer phoswich detector. The simulated small PET system employed LSO front layer LuYAP back layer phoswich detector modules and the module consisted of 8${\times}$8 arrays of dual layer crystals with 2 mm ${\times}$ 2 mm sensitive area coupled to a Hamamatsu R7600 00 M64 PSPMT. Sensitivities and variation of radial resolutions were simulated by varying the length of LSO front layer from 0 to 10 mm while the total length (LSO + LuYAP) was fixed to 20 mm for 10 cm diameter ring scanner. The radial resolution uniformity was markedly improved by using DOI information. There existed the optimal lengths of crystal layers to minimize the variation of radial resolutions. In 10 cm ring scanner configuration, the radial resolution was kept below 3.4 mm over 8 cm FOV while the sensitivity was higher than 7.4% for LSO 5 mm : LuYAP 15 mm phoswich detector. In this study, the optimal length of dual layer phoswich detector was derived to achieve high and uniform radial resolution.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.40 no.1
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• pp.1-14
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• 2022

In order to conduct rapid, accurate and safe surveying at the excavation site, In this study, the possibility of underground facility survey using drones and the expected effect of 3D visualization were obtained as follows. Phantom4Pro 20MP drones have a 30m flight altitude and a redundant 85% flight plan, securing a GSD (Ground Sampling Distance) value of 0.85mm and 4points of GCP (Groud Control Point)and 2points of check point were calculated, and 7.3mm of ground control point and 11mm of check point were obtained. The importance of GCP was confirmed when measured with low-cost drones. If there is no ground reference point, the error range of X value is derived from -81.2 cm to +90.0 cm, and the error range of Y value is +6.8 cm to 155.9 cm. This study classifies point cloud data using the Pix4D program. I'm sorting underground facility data and road pavement data, and visualized 3D data of road and underground facilities of actual model through overlapping process. Overlaid point cloud data can be used to check the location and depth of the place you want through the Open Source program CloudCompare. This study will become a new paradigm of underground facility surveying.

• Herbal Formula Science
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• v.32 no.1
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• pp.63-82
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• 2024

Objective : Saengkankunbi-tang (SKT) is used as a traditional Korean herbal formula for treatment of liver diseases. We investigated the hepatoprotective effects of SKT plus Epimedium koreanum Nakai (EKE) against arachidonic acid (AA) + iron-mediated cytotoxicity in HepG2 cells and carbon tetrachloride (CCl₄)-mediated acute liver damage in mice. Methods : The cyto-protective effects of SKT + EKE were determined by MTT assay, western blot and fluorescence activated cell sorting analysis. In mice, blood biochemistry and western blot were assessed in CCl₄-induced acute hepatic damage. The animal groups included vehicle-treated control, CCl₄, SKT (200 mg/kg/day), EKE (100 mg/kg/day), SKT (200 mg/kg/day) + EKE (100 mg/kg/day) and silymarin (200 mg/kg/day). Results : In HepG2 cells, pretreatment with SKT + EKE significantly suppressed cytotoxicity induced by AA + iron and reduced the expression of proteins related to apoptosis. In addition, pretreatment with SKT + EKE significantly prevented the increase in H₂O₂ production, GSH depletion, and lower mitochondrial membrane potential induced by AA + iron. In CCl₄-induced liver damage mice, the administration of SKT + EKE prevented the liver damage by inhibition of hepatocyte damage and expression of apoptosis proteins in liver. More importantly, in vitro and in vivo assay, SKT + EKE showed significant effect compare with SKT alone or EKE alone in all parameters. Conclusions : These results indicated that SKT + EKE could protect against oxidative stress-induced liver damage, and SKT + EKE is more effective than SKT alone or EKE alone.