• Journal of the Korea Institute of Building Construction
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• v.10 no.5
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• pp.113-119
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• 2010

Fire resistance and field tests for high-strength concrete(HSC) of 80MPa were carried out to evaluate whether or not it shows the same material properties even in the field condition of being mass-produced and supplied. As a result, it was found that fire resistant HSCs containing composite fiber(NY, PP) of 0.075% have great resistance to fire and spalling. In the field test, before the pumping air contents, slump flow, U-box, L-flow, compressive strength, gap of hydration temperature of interior and exterior of specimen and placing ratio per hour satisfied the required properties of HSC. However, after the pumping of HSC, as slump flow and L-flow were slightly less than required criterion, they need to be improved. In terms of hydration temperature of HSC, it was found to satisfy the related criterion. Packing ability as well as placing ratio per hour of HSC, which was about $44m^3$, show outstanding results. If slump flow of developed ternary HSC is improved after the pumping it can be useful for the construction of high-rise buildings.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2004.12a
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• pp.27-34
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• 2004

This experiment was carried out to examine the effects of morphology on properties of La-Co substituted SrM ferrite. The magnetic properties of calcined and sintered materials varied with the substitutional amount of La and Co elements in Sr-ferrite. In the substituted SrM ferrite, the atomic fraction x of La is directly related to the mole ratio n of iron oxide and the atomic fraction y of Co by equation x=2ny. The HcJ values of the calcined powder were about 270 kA/m and 240 kA/m with x=0.3 and K=0.2, respectively at stoichiometriy, n=6.0. Crystallites of the sintered material were grown with a plate shape, and their size decreased with increasing mole ratios. Such a shape was caused by the initial state of crystallite formed after calcination. In case of x=0.3 and n=6.0, Br was 415 mT and HcJ was 355 kA/m, and in x=0.2 and n=6.0, Br was 410 mT and HcJ was 370kA/m. The squareness in 2nd quarter of BH curve with x=0.2 was smoothly improved compared with x=0.3

• Horticultural Science & Technology
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• v.32 no.3
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• pp.408-414
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• 2014

The antimicrobial and antioxidant activities of different cultivars and parts of broccoli were investigated. The screening of antimicrobial activities for the floret and leaf extracts of 11 cultivars against selected gram positive (Staphylococcus aureus and Listeria monocytogenes) and gram negative bacteria (Escherichia coli O157:H7 and Salmonella enteritidis) were conducted. The AMG cultivar showed the highest antimicrobial activity against S. aureus with the floret and leaf extracts (12.83 and 13.00 mm). Antibacterial activity against L. monocytogenes was strongest with floret extract of NJ cultivar (13.58 mm) and leaf extract of YDR cultivar (13.92 mm). Moreover, the size of inhibition zone against L. monocytogenes was bigger than those of 4 kinds of pathogenic bacteria. Both floret and leaf extracts of Grd cultivar showed the highest antimicrobial activity against E. coli O157: H7, but there was no difference between floret and leaf extracts. Floret extract o f NJ cultivar and leaf extract of NY and 0c cultivars were effective against S. enteritidis whereas leaf extract exhibited better antimicrobial effect than floret extract. These results showed that floret extract of NJ and leaf extract of 0c had the highest antioxidant activity which was 39.90 and 43.64%, respectively. The antioxidant activity of leaf extract was 1.5 times higher than that of floret extract. All cultivars except NJ showed that electron donating ability of leaf extract was higher than that of floret extract.

• Journal of Dental Rehabilitation and Applied Science
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• v.26 no.2
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• pp.169-178
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• 2010

Objective. This study was conducted to observe the effect on appendage muscle strength according to increase in occlusal vertical dimension. Materials and methods. Ten males with a mean age of 21 were selected. The tested occlusal splints were made at the position of increased occlusal vertical dimension of 2mm,3.5mm and 5mm from the intercuspal position. Before and after wearing occlusal splints, the appendage muscle strength were tested by Cybex II dynamometer (Lumex Inc., Ronkonkoma, NY, USA). Results. Statistical analysis using the paired t-test revealed significant differences for flexion and extension of the hip, pronation of the forearm, internal rotation of the shoulder, external and internal rotation of the knee, and dorsiflexion and plantarflexion of the ankle (p<0.05). Conclusions. As the result of this study, we conclude that when occlusal vertical dimension was increased, most of mean muscular strength values were increased. Especially at the position of 3.5mm increased vertical dimension displayed the highest mean muscular strength value than other positions.

• Food Science and Preservation
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• v.21 no.1
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• pp.17-24
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• 2014

This study was conducted in order to evaluate the effect of postharvest ripening periods and packaging methods on maintaining the quality of fresh-cut winter squash. Winter squash (var. Bouchang) was ripened at $22^{\circ}C$ for 1 or 2 weeks after harvest. The samples were washed in tap water, sanitized in $100{\mu}L/L$ chlorine water, peeled, and cut into 16 parts. Samples were then vacuum packaged or non-vacuum packaged in $80{\mu}m$ nylon/polyethylene (Ny/PE) films and stored at $5^{\circ}C$ for 21 days. Results indicated that different postharvest ripening periods affected gas concentration, firmness, off-odor development, color, and overall quality of fresh-cut winter squash. Samples treated with 2-week ripening periods maintained quality with higher redness value and soluble solid content (SSC) and lower $CO_2$ concentration and off-odor development compared to samples treated with a 1-week ripening period. Non vacuum packaging was effective in increasing visual quality and reducing off-odor development. A combination treatment of 2-week ripening periods and non-vacuum packaging maintained good quality with the lowest off-odor development and the highest visual quality scores at the end of the storage period.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.1
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• pp.27-34
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• 2015

Heating patterns depending on the packaging materials were examined in order to investigate the causes of thermal deformation of packages used for ready-to-eat foods for microwave heating due to the non-uniformity of microwaves. Physical properties including tensile strength, heat-resistance and elongation of four different CPP grades were compared. High retortable CPP had higher sealing strength and heat resistance compared to the conventional CPPs. All CPP samples tested were proved to have melting temperatures around $160^{\circ}C$. However, they were all thermally deformed by microwave heating due to a limited penetration of microwave and non-uniform heating within the spicy sauce of high viscosity contained high salt, especially on the above the filling line and sealing edge of pouches. When the laminated stand-up pouches composed of G-PET/PET/PET/CPP and G-PET/PET/NY/CPP were retorted and microwaved, significant deformations were noticed in both samples after retorting. Besides, pouches contained titanium dioxide showed more intense thermal deformation than the control. When the $10{\mu}m$ aluminium foil was affixed on the pouch, small thermal deformation was observed only in the bottom layer. More studies are required to prevent the thermal deformation of packaging materials used for RTE foods during microwave heating by developing the technologies to increase the thermal stability of CPP layer and the modification of packaging design to modify the microwave access into the package.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.4
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• pp.377-383
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• 2013

This study examined the radiopacity of eight contemporary luting cements by direct digital radiography. Five disc-shaped specimens ($5mm{\times}1mm$) were prepared for each material tested (BisCem, Clearfil SA Luting, Duolink, Maxcem Elite, Multilink Speed, Panavia F 2.0, RelyX Unicem Clicker, V-link). The specimens were radiographed using a Kodak CS 7600 image plate (Carestream Health, Inc., Rochester, NY, USA) and an aluminum step wedge with a range of thicknesses (1.5 to 16.5 mm in 1.5 mm increments) and a 1 mm tooth used as a reference. A dental X-ray machine Kodak 2200 Intraoral X-ray System (Carestream Health, Inc., Rochester, NY, USA), operating at 70 kVp, 4 mA, 0.156 s and a source-to-sample distance of 30 cm, was used. According to international standards, the radiopacity of the specimens was compared with that of an aluminum step wedge using NIH ImageJ software (available at http://rsb.info.nih.gov/ij/).The data was analyzed by ANOVA and a Tukey's post hoc test. Maxcem Elite (5.66) showed the highest radiopacity of all materials, followed in order by Multilink Speed (3.87) and V-link (2.83). The radiopacity of Clearfil SA Luting (1.35), BisCem (1.33), Panavia F 2.0 (1.29) and Duolink (1.10) were between enamel (1.79) and dentin (0.19). RelyX Unicem Clicker (0.71) showed the lowest radiopacity, which was higher than that of dentin. All materials showed a radiopacity above the minimum recommended by the International Organization for Standardization and the American National Standards/American Dental Association with the exception of RelyX Unicem Clicker.

• The Journal of Korean Society for School & Community Health Education
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• v.25 no.1
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• pp.17-28
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• 2024

Background & Objectives: This study aimed to examine the relationship between subjective health perception and health behaviors among adolescents, utilizing raw data from the 8th Korea National Health and Nutrition Examination Survey (2019-2021) while distinguishing between genders. Methods: The study employed data from the 8th Korea National Health and Nutrition Examination Survey (2019-2020), recruiting students from 1st to 3rd grades in middle and high schools nationwide. Through population stratification, sample distribution, and sampling stages, a final sample of 1,065 adolescents aged 12 to 18 years was selected. The collected data were analyzed using SPSS 28.0 (IBM Corp., Armonk, NY, USA) at a significance level of .05. Results: Regarding the general characteristics of the subjects, no statistically significant differences were observed among male students based on school, family structure, and income. However, among female students, a significant difference in subjective health perception was noted, with higher perception among high school students compared to middle school students (p=.001). Significant differences in health behaviors were identified based on family structure for male adolescents, where those living with both parents exhibited more health-promoting behaviors than single-parent adolescents (p=.011). However, no significant difference was observed among female adolescents. In terms of health behaviors related to gender, regular exercise was found to significantly impact subjective health perception in male adolescents (p=.013), while breakfast habits were identified as significant influencers for female adolescents (p<.001). Conclusions: This study revealed gender differences in subjective health perception and health behaviors among adolescents. Based on these findings, there is a perceived need for the development of health promotion programs tailored to the unique needs of male and female adolescents.

• Journal of Physiology & Pathology in Korean Medicine
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• v.21 no.1
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• pp.214-218
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• 2007

The water extracts of Samultang (Samul) has been used for treatment of ischemic heart and brain damage in Oriental traditional medicine. However, little is known about the mechanism by which the water extract of Samul rescues cells from oxidative damages in cisplatin-induced ototoxicity. Cisplatin is a widely used chemotherapeutic agent that is also highly ototoxic. This study was designed to investigate the protective effects of Samul on ciplatin-induced ototoxicity in HEI-OC1 auditory cells and organ of Corti explant culture. Cisplatin markedly decreased the viability of HEI-OC1 auditory cells. However, treatment of HEI-OC1 cells with Samul significantly reduced cisplatin-induced cell death and apoptotic characteristics through reduction of intracellular peroxide generation. Cisplatin induced cytotoxicity in isolated and cultured hair cell progenitors from postnatal rat cochleae. These progenitor cells are isolated from the lesser epithelial ridge (LER, or outer spiral sulcus cell) area of pre-plated neonatal rat cochlear segments. However, Samul completely protected the morphological changes of organ of Corti and LER. Taken together, these data suggest that the protective effects of the water extracts of Samul against cisplatin may be mediated by the reduction of intracellular peroxide generation.

• Journal of Sasang Constitutional Medicine
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• v.15 no.2
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• pp.129-136
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• 2003

Diabetic nephropathy is defined that renal glomeruluses are damaged by diabetes melitus and proteins that are not excreted to urine normally are exhausted, or do not excrete waste matter to urine, so-called chronic renal failure state. Clinical stage is explained divided 5. If reached 4 or 5 stage, overt proteinuria is occurred to clinical nephropathy, and hypoalbuminemia, azotemia, hypertension, and edema become serious. Concept about edema is differing comprehension about mechanism of a disease, and treatment methodaccording to Sasang Constitution in Sasang Constitutional Medicine. I treated edemtous Soyangin(少陽人) patient with Dojeokgangkitang(導赤降氣湯) who diagnosed as diabetic nephropathy and wrongly treated in Soeumin. I have got good results, so I do case study.