• Journal of the Korean Geotechnical Society
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• v.38 no.4
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• pp.21-32
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• 2022

Steel pile foundations are widely used for offshore constructions due to their high bearing capacity and efficiency. Typically, offshore structures that have reached the end of their design life are required to be demolished. However, pile foundations are often left on site due to technical and economic limitations. The pile left on the site not only pollutes the environment, but can also cause obstacles for the construction of new structures. Therefore, research is required to completely eliminate these foundations at the site. In this study, a new type of double-wall pile foundation that can drastically reduce the pull-out load was conceptually proposed, and a series of model tests were performed to validate the performance of the double-wall pile foundation. The installation and extraction of the double-wall pile were simulated in dry sand in the model test, and the measured up-lift load was compared to that of the conventional pile. According to the result, the maximum up-lift load induced by the decommissioning of the double-wall pile was reduced by 45% when compared to the traditional pile in dense sand. This study verified the mechanism for reducing the up-lift load of the double-wall foundation and confirmed the possibility of completely decommissioning a pile that has reached the end of its nominal service life.

• Korean Journal of Poultry Science
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• v.35 no.4
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• pp.367-373
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• 2009

This experiment was conducted to determine optimum dietary levels of dietary energy and protein for laying performance and egg quality in organic laying hens. In a $2{\times}3$ factorial arrangement, 360 Hy-Line pullets (21 wk of age) were randomly assigned to experimental diets with 2,800, 3,080, and 3,360 kcal of ME/kg of diet, each containing 16 and 18% CP, respectively. Each dietary treatment was replicated 4 times, and feed and water were provided ad libitum. Experimental birds were raised in floor and received 14h of light throughout 52 weeks of experimental period. The birds were observed for feed consumption, egg production, egg weight, egg mass, feed conversion ratio, Haugh unit, shell thickness, and shell color at 30, 50, and 70 wk of age. Egg production, egg weight, and egg mass were higher (P<0.05) in hens receiving diets with 2,800 kcal/kg of ME/kg of feed than those fed diets containing 3,080 and 3,360 kcal of ME/kg of diets. Eggshell breaking strengths were not significantly different among the dietary ME and CP concentrations. Eggshell thickness was higher (P<0.05) in hens receiving diets with 3,360 kcal of ME/kg of feed than those fed diets containing 2,800 and 3,080 kcal of ME/kg of diets at 50 and 70 week. With increasing in dietary energy levels, the concentrations of blood total cholesterol were also significantly increased. Overall, the laying hens fed organic diet of 2,800 kcal ME/kg and 16% CP showed superior egg production than those of other dietary regimens.

• Tuberculosis and Respiratory Diseases
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• v.45 no.2
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• pp.397-403
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• 1998

Background: Little information is available concerning the value of bronchoscopy in patients with a lymphocytic exudative pleural effusion in which percutaneous pleural biopsy have been regarded as cornerstone in investigating the etiology. Recently, a few reports suggest that bronchoscopy may be more effective diagnostic method in patients with unexplained pleural effusion accompanied by hemoptysis or other roentgenographic abnormalities, such as mass, infiltrate, atelectasis. Method: Mter initial examinations of sputum and pleural fluid through thoracentesis in 112 patients(male 75 cases, female 37 cases, mean age 53.2 years) who were admitted for evaluation of the cause of pleural effusion, we performed bronchoscopy and closed pleural biology in most patients with undiagnosed lymphocytic exudate and compared the diagnostic yield of both invasive methods according to hemoptysis or other roentgenographic abnormalities, and investigated the sole diagnostic contribution of bronchoscopy. Results: Tuberculosis(57 cases, 51%) was the most common cause of pleural effusion. Percutaneous pleural biopsy showed more diagnostic yield than bronchoscopy regardless of presence or absence of other clinical or radiologic abnormalities. In 25 cases with unknown etiology after pleural biopsy, additional diagnostic yield by bronchoscopy was 36 % (4/11) in patients with associated features and only 7 % (1/14) with lone effusion, and, as the sole mean for diagnsosis in all patients with pleural effusion, was only 4.5%(5/12). Conclusion : In a region of high prevalence of tuberculosis as a cause of pleural effusion, percutaneous pleural biospy is more effective method when invasive method is required for confirmative diagnosis of unexplained lymphocytic exudative pleural effusion, and bronchoscopy is unlikely to aid in the diagnosis of lone pleural effusion.

• Journal of dental hygiene science
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• v.12 no.6
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• pp.572-582
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• 2012

The purpose of this research was to compare the oral health behaviors for children and teachers in toothbrushing facilities installed community child center related with teacher-supervised toothbrushing. This research was follow-up study from the Korean Dental Hygienists Association third project '2010 program of making of the diamond tooth'. 266 child support teachers were invited and 201 were included in the study (response rate: 75.6%). Statistical analysis conducted using PASW ver. 18.0 for Windows. The difference on the distribution of independent variables related with teacher-supervised toothbrushing was verified with chi-square test. The results of this research could be summarized as follows: The children in the teacher-supervised toothbrushing community child center, the practice rate of toothbrushing was higher than the children in the non-supervised toothbrushing community child center (p<0.05). Teachers offered children one of snacks and drinks per day independently of teacher-supervised toothbrushing (p>0.05). Most of participated teachers accepted to be responsible for oral health of children (73.4%) and demanded that improve facilities for a toothbrushing in community child center (77.2%). In conclusion, this study suggests that a programme of daily teacher-supervised toothbrushing can be effectively targeted into community child center.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.2
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• pp.154-159
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• 1995

In order to find out the effects of shading and nitrogen fertilizer on $NO_3^-$ accumulation in the edible parts of chinese cabbage, Cutivar, "Seoul", was cultivated in the pots under glasshouse condition with different rates of shading(0, 15, 30, 50, 75%) and nitrogen fertilization(recommended level, and double rate of recommended level). Leaf length, leaf width, yield (leaf weight), root width and root weight in the 15% shading rate showed the highest value, but decreased in the over 30% shading rates. The highest yield showed in the plot of the 15% shading rate with double rate application of recommended N level. High rate of shading increased the $NO_3^-$ accumulation, especially in midrib and outer leaf compared to leaf blade and inner leaf, respectively. The average $NO_3^-$ accumulation of edible parts of chinese cabbage are $4,872mg\;kg^{-1}$(outer midrib), $2,363mg\;kg^{-1}$(inner midrib), $1,405mg\;kg^{-1}$(outer leaf blade) and $727mg\;kg^{-1}$(inner leaf blade). $NO_3^-$ accumulation of outer midrib in the plots of double application of recommended N level were no difference between shading rate containing $5,000{\sim}6,000mg\;kg^{-1}$ $NO_3^-$, while in the plots of recommended N level it was increased by elevating shading rate. It was concluded that overuse of nitrogen fertiliration for chinese cabbage in glasshouse condition might lead to increase $NO_3^-$ accumulation. It could be advisable to cut out both the out leaf blade and outer midrib which might accumulate the high concentration of $NO_3^-$ before consumption.