• Journal of the Korean Geotechnical Society
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• v.33 no.1
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• pp.79-91
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• 2017

An experimental study has been conducted by using the Cyclic Direct Simple Shear apparatus to evaluate the influence of average and cyclic shear stresses on the undrained shear failure behavior of marine silty sand considering various relative densities. The obtained results show that despite using different relative densities, similar trends were gained in the cyclic shear deformation. Moreover, the cyclic shear deformation is affected mainly by the average and cyclic shear stresses. The number of cyclic loads for failure is significantly affected by the cyclic shear stress ratio and relative density, and is less affected by the average shear stress ratio. The proposed three-dimensional stress-dependent failure contour can be used effectively to assess the soil shear strength considering various relative densities in the design of foundation used for offshore structures.

• The Journal of the Korean Society for Microbiology
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• v.18 no.1
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• pp.53-58
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• 1983

Enterotoxigenic E. coli is one of causative agents of the infantile diarrhea and traveler's diarrhea. A modified infant mouse assay(IMA) was developed for the detection of heat stable enterotoxin (ST) of E. coli isolated from diarrheal and control infants and assay system was established with using enterotoxin producing reference strains. The supernatant of the 24 hour-shaking culture of E. coli in Casamino Acid Yeast Extract Salt Broth(CYES-2) was ingested orally into the 2-4 day old ICR mice. After the mice were kept at $25^{\circ}C$ for 4 hours, they were sacrificed and the gut weight body weight ratio(GW/BW) was taken as the index of fluid accumulation induced by heat stable enterotoxin of E. coli. The results obtained were as follows; 1. The GW/BW responses of IMA tested with enterotoxin reference strains of E. coli(E. coli O148H28:$ST^+LT^+$, E. coli $O78H^-:ST^+LT^+$, E. coli O15H11:$ST^-LT^+$, E. coli O1H7:$ST^-LT^-$) appeared ta be ST dose-dependent, and not LT-dependent. From the dose-response curve, $25{\mu}l$ of culture supernatant was determined as test amount of the IMA. 2. Frequency distribution of IMA result from 643 strain of E. coli showed normal distribution at low GW/BW ratio and dispersed pattern at high GW/BW ratio. The GW/BW ratios of $0.056{\pm}0.004(mean{\pm}SD)$ of normal distribution which distributed from 0.044 to 0.068(P<0.01) was considered as ST negative. Thus the GW/BW ratio above 0.069 could be regarded as ST positive.

• Journal of the Semiconductor & Display Technology
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• v.21 no.4
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• pp.53-58
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• 2022

Shape changes of hard mask play a key role in the aspect ratio dependent etch (ARDE). For etch process using high density and energy ions, deformation of hard mask shape becomes more severe, and high aspect ratio (HAR) etch profile is distorted. In this study, polygonal geometric model for shape-deformation of amorphous carbon layered hard mask is suggested to control etch profile during the process. Mask shape is modeled with polygonal geometry consisting of trapezoids and rectangles, and it provides dynamic information about angles of facets and etched width and height of remained mask shape, providing important features for real-time HAR etch profiling.

• Journal of Biosystems Engineering
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• v.18 no.3
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• pp.262-269
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• 1993

Stress relaxation behaviors of the cucumber under bending moment were tested with UTM at three levels of loading rate and initial deflection ratio. Sample cucumber was selected from three cultivars of cucumber, Cheongjangmadi, Baekdadagi, and Gyeousalicheongjang, because these cultivars are the most popular grown cultivars in Korea. When the bending moment was applied to the cucumber sample, the effective span between simple supports was held a constant value of 116mm with consideration of the selected sample length. The objectives of this study were to develop the rheological models such as linear and nonlinear models of the stress relaxation for the cucumber samples, and to investigate the effects of loading rate and initial deflection ratio on the stress relaxation behavior of the cucumber. The results of this study may be summarized as follows : 1. Stress relaxation behavior of the cucumber could be well described by the generalized Maxwell model for each level of deflection ratio. But the stress relaxation behavior of the sample was found to be initial deflection ratio and time dependent, and it was represented the nonlinear viscoelastic model as a function of initial deflection ratio and time. 2. Stress relaxation behavior of the cucumber samples was very highly affected by the loading rate and the initial deflection ratio. The more loading rate and initial deflection ratio resulted in the more initial bending stress and after stress relaxation progressed more rapidly. 3. At the same test conditions, it was found that the stress relaxation rate of Cheongjangmadi was faster than that of other cultivars.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.11
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• pp.223-234
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• 2021

This study aims to examine whether operating cash flows influence banks' financial stability in Pakistan. The study employed annual panel data collected from annual reports of 20 commercial banks listed on the Pakistan Stock Exchange for the year 2011 to 2019. Free cash flow yield was taken as the dependent variable while cash flow ratio was selected as the independent variable, and net interest margin, income diversification, asset quality, financial leverage, the cost to income ratio, advance net of provisions to total assets ratio, capital ratio, financial performance, breakup value per share and bank size were taken as control variables. The study performed ordinary least square technique, random and fixed effects models, Hausman test, Lagrange multiplier test, descriptive and correlation analysis. Results showed that operating cash flows and net interest margin significantly and positively influenced banks' financial stability while the cost to income ratio and advances net of provisions to total assets ratio significantly and negatively associated with banks' financial stability. To improve financial stability, banks should become more cost-effective and enhance their liquidity levels by lowering lending activities. In the future, it would be useful to compare commercial and investment banks, also Islamic and conventional banks in the same research setting.

• The Journal of Asian Finance, Economics and Business
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• v.8 no.3
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• pp.977-985
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• 2021

The main aim of the study is to provide empirical evidence about the association between stock market exchange data and weighted price index. This research utilized monthly reported data from the Amman stock exchange market (ASE) and the Central Bank of Jordan (CBJ). The weighted price index was employed as the dependent variable and the independent variables were weighted price index (WPI), turnover ratio (TOR), number of trading days (NTD), price-earnings ratio (PER), and dividends yield ratio (DY). The time period of the study was from January 2015 to October 2020. The study's methodology follows a quantitative approach using the multiple regression method to test the hypotheses of the study. The final results of the study provided conclusive evidence that the market-weighted price index is strongly and positively correlated to three predetermined variables, namely; turnover ratio, price-earnings ratio, and dividend yield but no evidence was obtained for the effect of the number of trading days. The finding of the current study proved that the market price index is not only influenced by macro factors, but also by other variables assumed to not beneficial for the judgment of price index movements.

• Proceedings of the Korean Vacuum Society Conference
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• 2006.02a
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• pp.138-138
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• 2006

• Journal of Korean Neurosurgical Society
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• v.43 no.4
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• pp.177-181
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• 2008

Objective : Hydrocephalus is a common sequelae of aneurysmal subarachnoid hemorrhage (SAH) and patients who develop hydrocephalus after SAH typically have a worse prognosis than those who do not. This study was designed to identify factors predictive of shunt-dependent chronic hydrocephalus among patients with aneurysmal SAH, and patients who require permanent cerebrospinal fluid diversion. Methods : Seven-hundred-and-thirty-four patients with aneurysmal SAH who were treated surgically between 1990 and 2006 were retrospectively studied. Three stages of hydrocephalus have been categorized in this paper, i.e., acute (0-3 days after SAH), subacute (4-13 days after SAH), chronic (${\geqq}14$ days after SAH). Criteria indicating the occurrence of hydrocephalus were the presence of significantly enlarged temporal horns or ratio of frontal horn to maximal biparietal diameter more than 30% in computerized tomography. Results : Overall, 66 of the 734 patients (8.9%) underwent shunting procedures for the treatment of chronic hydrocephalus. Statistically significant associations among the following factors and shunt-dependent chronic hydrocephalus were observed. (1) Increased age (p < 0.05), (2) poor Hunt and Hess grade at admission (p < 0.05), (3) intraventricular hemorrhage (p < 0.05), (4) Fisher grade III, IV at admission (p < 0.05), (5) radiological hydrocephalus at admission (p < 0.05), and (6) post surgery meningitis (p < 0.05) did affect development of chronic hydrocephalus. However the presence of intracerebral hemorrhage, multiple aneurysms, vasospasm, and gender did not influence the development of shunt-dependent chronic hydrocephalus. In addition, the location of the ruptured aneurysms in posterior cerebral circulation did not show significant correlation of development of shunt-dependent chronic hydrocephalus. Conclusion : Hydrocephalus after aneurysmal subarachnoid hemorrhage seems to have a multifactorial etiology. Understanding predisposing factors related to the shunt-dependent chronic hydrocephalus may help to guide neurosurgeons for better treatment outcomes.

• Journal of Trauma and Injury
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• v.22 no.2
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• pp.233-241
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• 2009

Purpose: Alcohol is a major risk factor for injuries, but little is known about the relationship between chronic drinking pattern and injuries. The purpose of this study was to evaluate the incidence of alcohol-related injuries and the differences in the characteristics of the injuries between Alcohol Use Disorder Identification Test (AUDIT) categories. Methods: Among a representative sample of the third Korea National Health and Nutrition Examination Survey. 7,697 adults answered questions about injuries, drinking patterns, and socioeconomic status. Incidences of alcohol-related injuries and of non-alcohol-related injuries were calculated, and the relative ratio of injuries between AUDIT categories was analyzed. Results: The incidences of all injuries and alcohol-related injuries were 69.2 and 6.8 per 1000 person-year. After adjustment, the incidences of non-alcohol-related injuries showed no differences between AUDIT categories. But the adjusted relative ratios (RRs) of alcohol-related injuries were 3.73 (95% CI: 1.54~8.99) and 7.70 (95% CI: 3.61~16.44) for risk drinkers and for alcohol-dependent drinkers respectively. No specific body part could be identified as being frequently injured in cases of risk drinkers and alcohol-dependent drinkers. In contrast, the adjusted RRs of fractures, bruises, and open wounds were 1.76 (95% CI: 1.03~3.02), 1.73 (95% CI: 1.15~2.61), and 1.85 (95% CI: 1.17~2.93) for alcohol-dependent drinkers. Assaults occurred 4.66 times more frequently in alcohol-dependent drinkers. Conclusion: Alcohol-related injuries occur more frequently as the person becomes more dependent on alcohol. Fractures, Bruises, open wounds, and assaults occur more frequently in alcohol-dependent drinker. This study suggests that efforts should be carried out in the ED to screen and treat alcohol-use disorders associated with patients injured after drinking.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.26 no.5
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• pp.881-889
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• 2002

Newly developed continuous indentation technique has made nondestructive assessment of tensile properties possible. The present study was undertaken to determine new parameters for indicating time-dependent material degradation of petro-chemical plant. Continuous indentation tests were performed for Cr-Ni steel and Cr-Mo steel which are widely used as facilities of petro-chemical plant. From the results, it was found that yield strength and tensile strength cannot be used as general degradation parameters because the changes in the strengths with aging time didn't show any tendency. On the other hand, work hardening exponent and yield ratio showed consistent tendency with increasing aging time. Therefore, nam attention of this work was paid on them as new degradation parameters, and the in-field applicability of the parameters was evaluated and discussed.