• Structural Engineering and Mechanics
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• v.61 no.4
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• pp.497-510
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• 2017

A framed structure may be composed of two sub-structures, which are linked by a hinged joint. One sub-structure is the primary system and the other is the secondary system. The primary system, which is subjected to the periodic external load, can give rise to an auto-parametric resonance of the second system. Considering the geometric-stiffness effect produced by the axially internal force, the element equation of motion is derived by the extended Hamilton's principle. The element equations are then assembled into the global non-homogeneous Mathieu-Hill equations. The Newmark's method is introduced to solve the time-history responses of the non-homogeneous Mathieu-Hill equations. The energy-growth exponent/coefficient (EGE/EGC) and a finite-time Lyapunov exponent (FLE) are proposed for determining the auto-parametric instability boundaries of the structural system. The auto-parametric instabilities are numerically analyzed for the two frames. The influence of relative stiffness between the primary and secondary systems on the auto-parametric instability boundaries is investigated. A phenomenon of the "auto-parametric internal resonance" (the auto-parametric resonance of the second system induced by a normal resonance of the primary system) is predicted through the two numerical examples. The risk of auto-parametric internal resonance is emphasized. An auto-parametric resonance experiment of a ${\Gamma}$-shaped frame is conducted for verifying the theoretical predictions and present calculation method.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.7
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• pp.910-913
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• 2004

Insulin-like growth factor binding protein-3 (IGFBP-3) gene is a structural gene associated with the growth and development of the animals. The present investigation was carried out to unravel nucleotide sequence and polymerase chain reactionrestriction fragment polymorphism (PCR-RFLP) of IGFBP-3 gene in buffalo. Genomic DNA was isolated from a total of 157 animals belonging to Murrah, Surti, Jaffarabadi and Nagpuri breeds of Indian riverine buffalo. A 655 bp of IGFBP-3 gene was amplified in all the breeds and amplicons were digested with Hae III, Taq I and Msp I restriction enzymes. On digestion with Hae III yielded single restriction pattern of 8 fragments of sizes 201, 165, 154, 56, 36, 19, 16 and 8 bp in all the animals studied. Similarly Taq I and Msp I also revealed single restriction pattern yielding fragments of sizes 240 and 415 bp and 145 and 510 bp, respectively. This shows nonpolymorphic nature of restriction sites in buffalo. Nucleotide sequencing of 587 bp of IGFBP-3 gene in Murrah buffalo was done and submitted to the GenBank (Accession No. AY304829). Nucleotide sequencing revealed an addition of 4 bases in the intronic region as compared to cattle.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.25 no.6
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• pp.501-510
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• 1992

Lipid prooxidants in sardine skin was characterized. Prooxidants in the sardine skin extract with 0.05M phosphate buffer was purified by successive chromatography on Sephadex G-200, DEAE-Sephadex A-50 and CM-Sephadex A-50. Prooxidants of sardine skin exist mainly in the intermediate molecular weight fractions. Observations of the thermounstability and optimum pH(pH 7.0) suggest that the major prooxidants are enzymes and hemoproteins. They can oxidize well both free and esterified linoleic acid and form conjugated hydroperoxides. From these results, the major prooxidants in sardine skin are assumed to be lipoxygenase-like enzymes.

• Journal of the Korean Institute of Intelligent Systems
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• v.23 no.6
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• pp.505-510
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• 2013

In order to detect and identify the GPS clock anomaly in the Differential GPS real environment, this paper addresses a method for minimizing the measurement noise of reference receivers. It estimates the real measurement noise that removed the uncommon error source from pseudorange measurement to minimize the measurement noise. Based on the output of two reference receivers, it first removes the uncommon errors, then optimizes the measurement noise by applying the correction data. Finally, it detects and identifies the satellite clock anomaly using the minimized measurement noise. The method will increase the availability of current DGPS reference system.

• Journal of Nutrition and Health
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• v.43 no.4
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• pp.395-403
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• 2010

This study was conducted to examine the dietary behaviors with 510 high school students (260 males and 250 females) residing in Seoul. The average age of male and female students were 16.3 and 16.4 years old, respectively. Mean height and weight of male students were 174.1 cm and 65.9 kg and those of female students were 161.6 cm and 52.5 kg. The body mass index (BMI) of male and female students were $21.7\;kg/m^2$ and $20.1\;kg/m^2$, respectively, which were within the normal range. Students skipped breakfast more than once a week were 41.1% of males and 44.4% of females. More than 40% of the male and female students skipped breakfast frequently. The mean mini dietary assessment index score of male and female students were 30.6 and 29.6 out of total 50 index scores, respectively. Female students perceived significantly less healthy and fatter than male students. Furthermore, body image satisfaction of the female students was lower than that of male students. Female students were more significantly concerned with body image and desired a thin body shape. Only 22.7% of male students and 6.4% of female students exercised regularly, and the frequency, time, and intensity of exercise in the male students were significantly higher than those of female students.

• Proceedings of the KSRS Conference
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• 2007.10a
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• pp.49-52
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• 2007

This study uses empirical method to estimate absorption coefficient of colored dissolved organic matter $(a_{dom})$ from GOCI satellite data with the relationship between band ratio of remote sensing reflectance $(R_{rs})$ and $a_{dom}$. For development of $a_{dom}$ estimation algorithm, the used data is in-situ data about ocean optical properties in the around seawater area of the Korean Peninsula during 1998 - 2005. The relationship of $R_{rs}$(412)/$R_{rs}$(555), $R_{rs}$(443)/$R_{rs}$(555), $R_{rs}$(490)/$R_{rs}$(555), $R_{rs}$(510)/$R_{rs}$(555) and $a_{dom}$(412) showed $R^2$ values of 0.707, 0.707, 0.597 and 0.552, respectively. The spectrum of $a_{dom}({\lambda})$ is shape of exponential function $a_{dom}({\lambda})$ value decreases with increasing wavelength. For estimation of $a_{dom}$ from satellite data, we developed an algorithm from the relationship of $a_{dom}$(412) and $R_{rs}$(412)/$R_{rs}$(555). This algorithm was employed on SeaWiFS imagery to estimate $R_{rs}$(412) in the South Sea, East Sea, Yellow Sea and northern East China Sea areas. Also, SeaDAS-derived $a_{dg}$(412) from same SeaWiFS imagery, These $a_{dg}$(412) was then compared with in-situ and empirical-algorithm-derived $a_{dom}$(412), but these values were different. We think two points that such different values are caused by discrepancy related to failure of standard atmospheric correction scheme, the other are caused by error related to definition of $a_{dom}$(412) and $a_{dg}$(412).

• Journal of Preventive Medicine and Public Health
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• v.48 no.4
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• pp.216-224
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• 2015

Objectives: Decreased fertility and impaired health owing to early menopause are significant health issues. Smoking is a modifiable health-related behavior that influences menopausal age. We investigated the effects of smoking-associated characteristics on menopausal age in Korean women. Methods: This study used data from the Korea National Health and Nutrition Examination Survey from 2007 to 2012. Menopausal age in relation to smoking was analyzed as a Kaplan-Meier survival curve for 11 510 women (aged 30 to 65 years). The risk of entering menopause and experiencing early menopause (before age 48) related to smoking were assessed using a Cox proportional hazards model. Results: The menopausal age among smokers was 0.75 years lower than that among non-smokers (p<0.001). The results of the Cox proportional hazards model showed pre-correction and post-correction risk ratios for entering menopause related to smoking of 1.26 (95% confidence interval [CI], 1.09 to 1.46) and 1.27 (95% CI, 1.10 to 1.47), respectively, and pre-correction and post-correction risk ratios for experiencing early menopause related to smoking of 1.36 (95% CI, 1.03 to 1.80) and 1.40 (95% CI, 1.05 to 1.85), respectively. Conclusions: Smokers reached menopause earlier than non-smokers, and their risk for experiencing early menopause was higher.

• Applied Chemistry for Engineering
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• v.20 no.5
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• pp.505-510
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• 2009

It is well known that the properties of concrete such as the compressive strength, water permeability, water tightness and durability are affected by micro-structure in hardened cement paste. Especially, for durability of concrete, watertightness of cementitious materials is the most critical property among various properties. Recently, many types of material such as organic and/or inorganic materials are used for watertightness of concrete. In this study, we examined the effect of fluorine-based emulsion on watertightness property. And we also discussed the change of microstructure and formation of hydrates in hardened cement paste by the addition of fluorine-based emulsion. Cement paste with fluorine-based emulsion showed improvement of watertightness by the surface activation of cement paste and by formation of $CaF_2$ fine crystals in cement pore structure.

• Journal of Chest Surgery
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• v.29 no.2
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• pp.235-238
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• 1996

Acquired tracheoesophageal fistula, a life threatening lesion, is rare but occurs most frequently alter prolonged mechanical ven ilation using a cuffed endotracheal tube. The mechanism of injury seems to be ischemia and inflammation of compressed trachea and esophagus by cuffed endotracheal tube. The patient was a 25 years old pregnant woman who was on prolonged mechanical ventilation for bacterial meningitis secondary to untreated otitis media. 40 days after mechanical ventilation, sudden subcutaneous empysema and pneumomediastinum ocurred and these were due to tracheoesophageal fistula. It was diagnosed with bronchoscopy and CT We performed tracheal repair with TA 60mm stapler and esophageal repair by interruted two layer suture with 410 vicryl and 510 prolene. A flap of sternocleidomastoid muscle was inserted between trachea and esophagus. Postoperative course was uneventful and the result of operation was acceptable by esophagography.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.6
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• pp.1026-1036
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• 2014

Real-time monitoring for environmental factors (temperature, salinity, chlorophyll-a, etc.) and fugacity of carbon dioxide ($fCO_2$) was conducted at an oyster Crassostrea gigas farm in Goseong Bay, south coast of Korea during 2-4th of November, 2011. Surface temperature and salinity were ranged from $17.9-18.7^{\circ}C$ and 32.7-33.8, respectively, with daily and inter-daily variations due to tidal currents. Surface $fCO_2$ showed a range of $390-510{\mu}atm$ and was higher than air $CO_2$ during the study period. Surface temperature, salinity and $fCO_2$ are showed significant correlations with chl.-a and nutrients, respectively. It means when chl.-a value is high in surface water of the oyster farm, active biological production consume $CO_2$ and nutrients from environments and produce oxygen, suggesting a tight feedback between biological processes and environmental reaction. Thus, factors affecting the surface $fCO_2$ were evaluated using a simple mass balance. Temperature and biological productions by phytoplankton are the main factors for $CO_2$ drawdown from afternoon to early night, while biological respiration increases seawater $CO_2$ at night. Air-sea exchange fraction acts as a $CO_2$ decreasing gear during the study period and is much effective when the wind speed is higher than $2-3m\;s^{-1}$. Future studies about organic carbon and biological production/respiration are required for evaluating the roles of oyster farms on carbon sink and coastal carbon cycle.