• KSCE Journal of Civil and Environmental Engineering Research
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• v.35 no.2
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• pp.299-306
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• 2015

The quality for the domestic pavement is evaluated based on flexural strength at the age of 28 days in accordance with KS regulation. Most specimens of the flexural tensile strength used currently are relatively large ones with a dimension of $150{\times}150{\times}550mm$. Accordingly, it is difficult to treat the specimens, and the utilization of a curing tank is low. In this paper, the study tried to resolve the problem by specimen size specified in the code. For this purpose, a flexural strength test was conducted according to the log scale within the specimen size specified by the KS. And, based on the results of this experiment, a comparative analysis was conducted using the prediction formula of Size Effect Law (SEL) proposed by Bazant to examine the correlation between specimen sizes, so as to use the result as basic data for the reduction of the specimen size in the quality evaluation of concrete pavement.

• The Journal of Asian Finance, Economics and Business
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• v.9 no.2
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• pp.29-36
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• 2022

This study uses the panel probit model to investigate and evaluate the relationship between exchange rate regimes, political stability, and carbon dioxide during currency crises. To understand currency crisis times, we study a panel dataset of seven South Asian nations that contain annual observations from 1996 to 2020. Furthermore, we created the EMPI exchange market pressure indicator to detect crises. Our results strongly suggested that fixed exchange rate is negatively associated with currency crises, with good regulatory quality and better effective governments. Simultaneously, the floating exchange rate is positively related to the currency crises in those countries where the rule of law has less adequately flowed. However, CO₂, exports, and interest rates are buoyantly associated with crises. The floating exchange rate, the rule of law, exports, and interest rate are associated positively and contribute more prone to the crisis episodes. Negatively associated variables contributed less amid crises episodes: fixed exchange rate regime, government effectiveness, and regulatory quality. Meanwhile, CO₂ has a positive relationship with a currency crisis and contributes more likelihood to the probability of a currency crisis. Countries that adopted the fixed exchange rates with effective governments and regulatory quality faced more minor currency crises.

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.2
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• pp.213-222
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• 2001

Cylindrical type ceramic filers, that is 60 O.D$\times$10t$\times$600L and 60 O.D$\times$10t$\times$1,000L were manufactured by vacuum forming processes using ceramic ray materials. For cylindrical type ceramic filters, porosity and bulk density were measured for, 80 to 90% and 0.3 to 0.4 g/㎤, respectively at uniform pore size of 41 to 45${\mu}{\textrm}{m}$. Bench scale candle filters (60$\psi$ $\times$10t$\times$600L) were tested using different dusts collected from many industries including chemical processing, glass processing and metal manufacturing pants. Collection efficiencies found out to range from 99.87% to 99.90%, while resistance coefficients from 1.1$\times$10(sup)11/$m^2$ to 1.7$\times$10(sup)11/$m^2$ . Full scale low density ceramic filters (60$\psi$ $\times$10t$\times$1,000L) were also tested at 1 atm, $600^{\circ}C$ to reveal the filtration efficiency, conditioning, and resistance coefficients using two different types of dust as chemical processing and metal refined processing. Darcys law resistance coefficients were measured to range 1.44$\times$10(sup)11/$m^2$ to 2.74$\times$10(sup)11/$m^2$, and collection efficiencies on the range 99.84 to 99.96%, Finally, results of long term performance test showed that filters were conditioned after 170hrs. Experimental conditions for effective filtration were examined under the condition 10 cm/sec face velocity, 3kg/$\textrm{cm}^2$ pulsing pressure, 5 min filtration cycle, and 300msec pulse opening time.

• Journal of Environmental Health Sciences
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• v.41 no.1
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• pp.11-16
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• 2015

Objectives: This study assessed the impact of the smoke-free law on secondhand smoke exposure in computer game rooms by measuring concentrations of particulate matter smaller than $2.5{\mu}m$($PM_{2.5}$). Methods: Indoor $PM_{2.5}$ concentrations were measured in 56 (during the smoke-free guidance period) and 118 computer game rooms (after the law went into effect) in four cities (Seoul, Cheonan, Daegu and Kunsan) in Korea. The number of smokers in the computer game rooms was also counted every five minutes. Results: Although a smoking ban had been implemented nationally, smoking was observed in 47% of the computer game rooms. Smoking density decreased from 1.62 persons per $100m^3$ during the guidance period to 0.32 persons per $100m^3$ after the smoke-free law. There is no statistically significant difference of $PM_{2.5}$ concentrations before and after the smoking ban. The $PM_{2.5}$ concentration was two times higher than the US NAAQS of $35{\mu}g/m^3$. The $PM_{2.5}$ concentration in computer game rooms without smokers was two times higher than the outdoor concentration. Conclusion: The smoke-free law in computer game rooms was complied with, even after the guidance period, in Korea. Indoor $PM_{2.5}$ concentration after smoke-free law implementation was high due to this non-compliance. High $PM_{2.5}$ concentration in computer game rooms without smokers might be due to smoking booths. The complete prohibition of smoking in computer game rooms should be implemented to protect patrons from secondhand smoke exposure.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.175-183
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• 1999

Mine tailings, field soils, and paddy soils around Jingok abandoned mine were analyzed In order to investigate their pollution levels of heavy metals and cyanide. The average contents of As, Cd, Cu. Hg. Pb, Zn, and CN￣in mine tailings were 3.94$\times$$10^3$, 14.3, 266, 6.13, 4.07$\times$$10^3$, 2.51$\times$$10^3$, and 1.19mg/kg, respectively. The pollution indices calculated by the tolerance level of Kloke were 32~58 and the pH values were slightly acidic in mine tailings. In the field and paddy soils of Jingok abandoned mine area except for soils nearby mine tailings, concentrations of the heavy metals were less than standards of soil pollution of agricultural area in the environmental protection law.

• YAKHAK HOEJI
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• v.32 no.1
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• pp.86-94
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• 1988

Some rheological properties of subfractions for dextran in the molecular weights range from $3{\times}10^4$ to $2{\times}10^6$ was investigated at room temperature. The dependence of the viscosity on concentration, shear rate, pH & ionic strength, temperature and solvent effect was observed. From the experimental data the Mark-Houwink viscosity equation in water at $25^{\circ}C$ was determined for samples having the molecular weight ranging from $3{\times}10^4$ to $2{\times}10^6$ as$[{\eta}]=3.1{\times}10^{-3}\;Mw^{0.39}(in\;dl/g)$. The intrinsic stiffness of the dextran backbone was estimated by evaluating the 'characteristic ratio' $C_{\infty}$, which is below the 0.082. In the concentrated region, the viscosity was decreased with increasing shear rate and was exponentially decreased with raising temperature, the viscosity showed the maximum value at neutral condition. From the experimental data, it was concluded that dextran chain, linked by the ${\alpha}-1$, 6-glucosidic linkage, behaves like a flexible random coil chain in aqueous solution, dextran solutions were pseudoplastic power law fluids among the empirical models of non-Newtonian behavior. Urea was an active reagent which increases the viscosity and swells dextran while pyrididine and glycerol were inactive reagents. Also, it could be estimated that the formation of gel structure is promote to the neutral state, the molecular weight larger than $2{\times}10^5$, when electrolytic concentration is IN and Ureas is use to solvent.

• Communications for Statistical Applications and Methods
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• v.12 no.2
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• pp.483-496
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• 2005

We consider the power law process which is assumed to have multiple changepoints. We propose a binary segmentation procedure for locating all existing changepoints. We select one model between the no-changepoints model and the single changepoint model by the Bayes factor. We repeat this procedure until no more changepoints are found. Then we carry out a multiple test based on the Bayes factor through the intrinsic priors of Berger and Pericchi (1996) to investigate the system behaviour of failure times. We demonstrate our procedure with a real dataset and some simulated datasets.

• Journal of the Korean Society of Groundwater Environment
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• v.5 no.2
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• pp.80-87
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• 1998

Since groundwater flow paths have one of the major roles to transport the radioactive nuclides from the radioactive waste repository to the biosphere, the discrete fracture network model is used for the rock block scale flow instead of the porous continuum model. This study aims to construct a three dimensional discrete fracture network to interpret the groundwater flow system in the study site. The modeling work includes the determination of the probabilistic distribution function from the fracture geometric and hydraulic parameters, three dimensional fracture modeling and model calibration. The results of the constant pressure tests performed in a fixed interval length at boreholes indicate that the flow dimension around boreholes shows mainly radial to spherical flow pattern. The fracture transmissivity value calculated by Cubic law is 6.12${\times}$10$\^$-7/ ㎡/sec with lognormal distribution. The conductive fracture intensity estimated by FracMan code is 1.73. Based on this intensity, the total number of conductive fractures are obtained as 3,080 in the rock block of 100 m${\times}$100 m${\times}$100 m.

• Journal of Astronomy and Space Sciences
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• v.14 no.2
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• pp.179-193
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• 1997

We use B band CCD images to investigate the surface brightness distributions and dynamical properties of 29 Galactic globular clusters. Model fits suggest that 22 clusters show King type surface brightness profiles, while 7 clusters are characterized by power law cusp profiles. For the King type clusters, concentration parameters $(c=log(r_{t}/r_{c}))$ range from 1.20 to 2.10, and core radii are 0.4 to 1.9 pc. The mean value of power law slopes of 7 cuspy clusters was estimated as ${alpha}=1.011{\pm}0.065$. Total masses of King type globular clusters are in the range of $1.7{ imes}10^4M_{odot}$ to $1.0{\times}106M_{\odot}$ with a mean of $1.7{\times}10^5M_{\odot}$. A significant positive correlation between mass and mass-to-light ratio of King type globular clusters has been confirmed with a Pearson's correlation coefficient r = 0.52 and a confidence level of 99%. Our data also confirm a linear relation between total mass and absolute magnitude of King type globular clusters.

• Journal of Arbitration Studies
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• v.25 no.2
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• pp.97-118
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• 2015

As China has quickly emerged as a global economic power, the total number of international commercial disputes arbitrated by Chinese arbitral institutions has increased dramatically. Along with this, the annulment procedure of arbitral awards in China have been newly brought to the fore. In accordance with the historical background and the demand of the times, the Chinese annulment procedure of arbitral awards reveals distinctive Chinese features. Although it was enacted in the face ofof an unwarranted prejudice against the dispute settlement system by arbitration as well as a deep mistrust of domestic arbitral institutions, the annulment procedure of arbitral awards showed a certain degree of justification and rationality in its initial stages of legislation. However, it is also the case that it has not adapted well to new domestic or foreign arbitration circumstances in the last twenty years. At present, there is a keen interest in revisions to and debates on arbitration law of China. It is necessary to take an active part in the amendment discussion and process of arbitration law. Moreover, we need to reform the annulment procedure of arbitral awards in order to meet the global trend of arbitration law.