• Korean Journal of Medicinal Crop Science
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• v.8 no.4
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• pp.362-372
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• 2000

This study was conducted to obtain the basic information on the production of high yield and qualitied yam in Andong, major yam-producing district, in Kyongbuk province, using three major Yam cultivars, such as Danma, Jangma and Alata (round type). Alata showed the longest tuber width while Jangma showed the longest tube length. Danma showed the highest tube yield at 2,123 kg/10a. Tubes of Alata had higher dry ratio than those of other cultivars, suggesting that Alata could be used as good processing materials. Characteristics of top parts, such as vine length, leaf number, and lateral vine number showed typical sigmoid curves. Tuber characteristics such as length, width and fresh weight of tuber were linearly increased as the growth period was progressed. Relative growth rate (RGR) for new tuber and stem reached the highest value at 86 DAT (days after transplanting). There were similar tendencies among the cultivars in net assimilation rate (NAR). The highest crop growth rate (CGR) was appeared at 156 DAT regardless of cultivars. In the changes of leaf area ratio (LAR), there were significant differences among three cultivars. LAR were decreased at 86, 106 and 136 DAT for Alata, Danma and Jangma, respectively. However, specific leaf weight (SLW) was greatly increased at 176 DAT, and leaf area index (LAI) was decreased at 156 DAT in all cultivars.

• Journal of Korean Society of Steel Construction
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• v.20 no.4
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• pp.483-491
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• 2008

There has been much focus on the strong axis steel moment connections after the Northridge earthquake in 1994. However, research studieson the seismic behavior of weak axis moment connections could be hardly found despite the fact that these connection details have been frequently used as seismic details of MRF in Korea. Therefore, the objective of this research is to provide better knowledge on the seismic behavior of weak-axis steel moment connections, which can be widely applicable to many structures with similar characteristics. For this purpose, an experimental program was designed and performed with twotypes of weak-axis steel moment connections, namely the bracket type and WUF-B type, based on the survey of existing field data and literatures. Using the experimental results obtained from the quasi-static cyclic testing of these specimens, structural performances of the joints such as hysteretic curves, maximum strength capacities and the strain of reinforced bars were investigated. From the test results, the bracket-type connection was shown to have more than a 5% story drift capacity, compared with the WUF-B type connection's 4%. These specimens were also shown to have higher strength capacities than the nominal design strength. The bracket-type connection showed a slow strength degradation after maximum strength was researched. However,the WUF-B type connection showed a rapid strength degradation that caused brittle behavior.

• The Journal of Korean Obstetrics and Gynecology
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• v.24 no.2
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• pp.1-12
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• 2011

Objectives: The object of this study was to observe the in vitro antibacterial effects of Chungdae-tang aqueous extracts, traditionally used for treating various gynecological diseases including vaginitis in Korea against Gardnerella vaginalis, and combination effects of Chungdae-tang extracts with Clindamycin were also monitored in this study. Methods: Antibacterial activities against Gardnerella vaginalis of Chungdae-tang aqueous extracts were detected using standard agar microdilution methods. In addition, the effects on the bacterial growth curve were also monitored at MIC and MIC${\times}$2 levels. The combination effects of Chungdae-tang aqueous extracts with Clindamycin were observed by Checkerboard microtiter assay, and the effects of bacterial growth curve treated with or Chungdae-tang aqueous extracts MIC+Clindamycin MIC, 1/2MIC and 1/4MIC, respectively. In the present study, Gardnerella vaginalis were incubated under $37^{\circ}C$, 10% $CO_2$; and bacterial growth curves were calculated at 24, 48, 72, 96 and 120hrs after incubations. Results: MIC of Chungdae-tang aqueous extracts against Gardnerella vaginalis were detected as $3.906{\pm}2.344$(0.782~6.250) mg/$m\ell$, respectively. MIC of Clindamycin was detected as $0.010{\pm}0.006$(0.004~0.016) ${\mu}g/m\ell$ at same conditions. In addition, Clindamycin and Chungdae-tang aqueous extracts also showed marked dosage-dependent inhibition of bacterial growth, and more dramatical inhibitions were detected in Clindamycin+Chungdae-tang aqueous extracts MIC treatment as compared with each of single Clindamycin MIC and Chungdae-tang aqueous extracts MIC treatments, respectively. In addition, quite similar inhibitory effects on bacterial growth were detected in Clindamycin 1/4 MIC+Chungdae-tang aqueous extracts MIC treatment as compared with single Clindamycin MIC treatment in the present study. FIC index in combination of Chungdae-tang and Clindamycin were detected as $0.775{\pm}0.285$ (0.500~1.250) at Checkerboard microtiter assay. Conclusions: The results obtained in this study suggest that Chungdae-tang aqueous extracts showed antibacterial effects against Gardnerella vaginalis, and it also showed dosage-dependent inhibitory effects on the bacterial growth. In addition, combination treatment of Chungdae-tang aqueous extract with Clindamycin showed more potent inhibitory effects on the growth of Gardnerella vaginalis with FIC index $0.775{\pm}0.285$(0.500~1.250), respectively. It means, the combination of Chungdae-tang aqueous extract with Clindamycin is partially synergistic effects. It, therefore, is expected that effective dosages of Clindamycin will be reduced to 1/4 or over 1/4 levels as combination with Chungdae-tang extracts, respectively.

• Radiation Oncology Journal
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• v.13 no.3
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• pp.285-289
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• 1995

Purpose : We compared the calcualted percent depth dose curves of 6 MeV electron beam to that of measured to evaluate the usefulness of Monte-carlo simulation method in radiation physics. Materials and Methods : The radiation dose values of 6 MeV electron beam using EGS4 code with one million histories in water were compared values that were measured from the depth dose curve of electron beam irradiated by medical accelerator ML6M. The central axis dose values were calculated according to the changing field size. such as $5{\times}5,\;10{\times}10,\;15{\times}15,\;20{\times}20cm^2$. Results : The value calculated showed a very similar shape to depth dose curve. The calculated and measured value of $D_max$ at $10{\times}10cm^2$ cone is 15mm and 14mm respectively. The calculated value of the surface radiation dose rate is $65.52\%$ and measured one is $76.94\%$. The surface radiation dose rate has varied from $64.43\%$ to $66.99\%$. The calculated values of $D_max$ are in the range between 15mm and 18mm. The calculated value was fitted well with measured value around the $D_max$ area, excluding build up range and below the $90\%$ depth dose area. Conclusion : This result suggested that the calculation of dose value can be replace the direct measurement of the dose for radiation therapy. Also, EGS4 may be a very convenient program to assess the effect of radiation dose using by personal computers.

• Journal of Korean Neurosurgical Society
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• v.30 no.7
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• pp.876-882
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• 2001

Objectives : Meningeal hemangiopericytoma is a rare tumor. Clinical and radiological features are similar to those of an ordinary meningioma. But its biological behavior is quite different from those of a meningioma as it brings profuse bleeding in the operation field, frequent recurrence and metastasis to other systemic organs even in the case of gross total resection. In order to find out the prognostic factors and to compare longterm outcome after various treatment modalities, the authors reviewed consecutive 20 operated cases of meningeal hemangiopericytoma to characterize their clinical features, surgical outcomes and effectiveness of the radiation therapy. Methods : Twenty patients with a hemangiopericytoma were treated between 1982 and 1999 in our department. They are composed of 13 patients of hemangiopericytoma and 7 patients who were initially diagnosed as angioblastic type meningioma and then confirmed as a hemangiopericytoma after review of their previous histopathology slides. The mean follow-up period was 99 months(1-256 months). The long-term outcomes after various treatment modalities were evaluated according to recurrence-free survival and image follow-up. Recurrence-free survival curves are compared between the patient groups according to the extent of removal and radiation therapy. Results : There were 10 cases of recurrence and 4 cases of distant metastases ; lung, liver and femur(2 cases) respectively. The 5-year recurrence rate was 37%, while the 10-year recurrence rose to 77%. There was also statistically significant difference of median recurrence-free survival between the completely-resected group(Simpson grade 1 or 2) and partially-resected group(Simpson grade 3 or 4 or 5) ; 137 months compared to 47 months, respectively(p=0.009). The median recurrence-free period after subtotal resection of tumor and postoperative radiotherapy was 47 months compared to 117 months of the patients who underwent gross total resection of tumor and did not receive radiotherapy. But radiation therapy alone did not show significant difference in recurrence-free survival. Marked tumor volume reduction and easy removal of tumors without bleeding were found in 2 recurred cases. Conclusion : The extent of tumor resection and presence of metastasis are the most important factors related to long-term outcome of the patients with hemangiopericytoma. Radiation therapy after the first operation did not have a role in extending the recurrence-free survival, but it affected favorably to decrease the size of residual mass and intraoperative bleeding during the second operation.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.97-107
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• 2020

In this study, finite element analysis was carried out through the finite element analysis program (ANSYS) to investigate the fire resistance of composite columns in fire. Transient heat transfer analysis and static structural analysis were performed according to ASTM E 119 heating curve and axial force ratio 0.7, 0.6, 0.5 by applying stress-strain curves according to temperature, and loading heating experiments were carried out under the same conditions. In addition, the nominal compressive strength of the composite column according to the heating time according to the standard(Eurocode 4) was calculated and expressed as the axial force ratio and compared with the analytical and experimental values. Through the analysis, As a result of finite element analysis, the fire resistance time was 180 minutes and similar value to the experimental value was obtained, whereas the fire resistance time 150 minutes and 60 minutes were derived from the axial force ratios 0.6 and 0.7. In addition, it was confirmed that the fire resistance time according to the axial force ratio calculated according to the reference equation (Eurocode 4) was lower than the actual experimental value. However, it was confirmed that the standard(Eurocode 4) was higher than the experimental value at the axial force ratio of 0.7. Accordingly, it is possible to confirm the fire resistance characteristics(time-axial force ratio relationship) of the SRC column at high axial force, and to use the experimental and anaylsis data of the SRC column as the data for verification based on Eurocode.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.26 no.1
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• pp.261-274
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• 2000

The o/w emulsions were prepared with saccharide surfactants which were sucrose monostearate(S160), sucrose distearate(S110), and POE(20) methyl glucose stearate(SSE20). And for emulsion the oils used were n-hydocarbon, squalane(SQ), liquid paraffin(LP), octylpalmitate(OP), octylstearate(OS), alkyl benzoate(AB), isostearyl benzoate(ISB). The structures of o/w emulsion droplet were investigated by laser light scattering and the fractal dimensions were calculated from light intensity curves. Increasing of concentration, chain length, and nonpolarity of oils, fractal dimensions of emulsion droplets were found greater. In general fiactal dimensions were varied from 1.7 to 2.8 and its structures were fractal But the fractal dimensions of octadecane( $C_{18}$), 50, and LP emulsified with S110 and S160 were varied from 3.0 to 3.2 and its structures were more dense. The overall fractal dimensions of S110 and S160 were varied from 2.1 to 2.6, that of SSE20 were varied from 1.5 to 2.1. So it was found that the structures of SSE20 system were less compact than that of S110 and S 160 system, because the hindrance effect of polyoxyehtylene group of SSE20 was stronger than that of sucrose of S160. The strucures of emulsion droplets changed according to the nature of emulsifiers and to compositions of oil substances which they contained, and the structures were found similar when the hydophilic moiety of emulsifiers was same.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.823-827
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• 2010

This study was conducted to assess the propriety of models for soil water characteristics estimation in anthropogenic soil through the measurement of soil water content and soil water matric potential. Soil profile was characterized with four different soil layers. Soil texture was loamy sand for the first soil layer (from soil surface to 30 cm soil depth), sand for the second (30~70 cm soil depth) and the third soil layers (70~120 cm soil depth), and sandy loam for the fourth soil layer (120 cm < soil depth). Soil water retention curve (SWRC), the relation between soil water content and soil water matric potential, took a similar trend between different layers except the layer of below 120 cm soil depth. The estimation of SWRC and air entry value was better in van Genuchten model by analytical method than in Brooks-Corey model with power function. Therefore, it could be concluded that van Genuchten model is more desirable than Brook-Corey model for estimating soil water characteristics of anthropogenic soil accumulated with saprolite.

• Korean Journal of Food Science and Technology
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• v.51 no.1
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• pp.1-6
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• 2019

Horse fat was vacuum-extracted from fatty tissues of Jeju and Halla horse meat and their physicochemical properties were compared to those of commercial lard and beef-tallow. For color, ${\Delta}E$ was found to be decreased when crystallized. Although acid values of horse fat were higher than those of lard and beef-tallow, p-anisidine and totox values were lower. The iodine value of beef-tallow was the lowest (44.61), and those of horse fat and lard were similar (57.53-57.74). Only horse fat contained ${\alpha}-tocopherol$. The contents of ${\gamma}-tocopherol$ in Jeju and Halla horse fat, lard, and beef-tallow were 7.08, 4.57, 2.13, and 1.91 mg/kg, respectively. Palmitoleic acid ($C_{16:1}$) was found in horse fat. Melting and crystallization curves of horse fat displayed two endothermic and exothermic peaks which were differentiated from lard and beef-tallow. These results indicated that horse fat demonstrates different physicochemical properties compared to lard and beef-tallow, when applied to various types of lipid products.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.32 no.1
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• pp.37-44
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• 2019

A bond-based peridynamic model has been reported dynamic fracture characteristic of brittle materials through a simple constitutive model. In the model, each bond is assumed to be a simple spring operating independently. As a result, this simple bond interaction modeling restricts the material behavior having a fixed Poisson's ratio of 1/4 and not being capable of expressing shear deformation. We consider a state-based peridynamics as a generalized peridynamic model. Constitutive models in the state-based peridynamics are corresponding to those in continuum theory. In state-based peridynamics, thus, the response of a material particle depends collectively on deformation of all bonds connected to other particles. So, a state-based peridynamic theory can represent the volume and shear changes of the material. In this paper, the perfect plasticity is considered to express plastic deformation of material by the state-based peridynamic constitutive model with perfect plastic flow rule. The elastic-plastic behavior of the material is verified through the stress-strain curves of the flat plate example. Furthermore, we simulate the high-speed impact on 3D granite model with a nonlocal contact modeling. It is observed that the damage patterns obtained by peridynamics are similar to experimental observations.