• Tunnel and Underground Space
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• v.17 no.4
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• pp.301-310
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• 2007

The prediction of temperature in the workings for the propriety examination for the development of a deep coal bed and the ventilation design is fairly important. It is quite demanding to obtain precise thermal conductivity of rock due to the variety and the complexity of the rock types contiguous to the coal bed. Therefore, to estimate the thermal conductivity corresponding to this geological situation and complex gallery conditions, a computing program which is TemPredict, is developed in this study. It employs Artificial Neural Network and calculates the climatic conditions in galleries. This advanced neural network is based upon the Back-Propagation Algorithm and composed of the input layers that are acceptant of the physical and geological factors of the coal bed and the hidden layers each of which has the 5 and 3 neurons. To verify TemPredict, the calculated result is compared with the measured one at the entrance of -300 ML 9X of Jang-sung production department, Jang-sung Coal Mine. The difference between the results calculated by TemPredict ($25.65^{\circ}C$) and measured ($25.7^{\circ}C$) is only $0.05^{\circ}C$, which is less than the allowable error 5%. The result has more than 95% of very high reliability. The temperature prediction for the main carriage gallery 9X in -425 ML under construction when it is completed is made. Its result is $28.2^{\circ}C$. In the future, it would contribute to the ventilation design for the mine and the underground structures.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.67-75
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• 2011

Domestic economic development, industrialization, and urbanization have brought along not only increased highway traffic but also elevated traffic noise levels. Thus, it is necessary to accurately predict the traffic noise levels in order to address the public demand of alleviating the noise levels in urban areas. In this study, the method of evaluating the sound power level of road traffic was investigated in terms of considering the types of road surface and vehicle, based on previous researches. Regarding CPX (Close Proximity Test) and Pass-by test, the measured noise data of Test Road of Korea Highway Corporation were utilized in order to construct the database of sound power levels of various vehicles. Specifically, the 38 noise measurement and analysis in 1/1-octave band frequencies at 12 pre-selected sites were carried out, considering topography and road surface. Finally, the comparison study was conducted between predicted and measured data in terms of traffic noise. The traffic noise prediction was based on the KRON (Korea Road Noise) program, which was developed being equipped wit 3-dimensional GUI. In addition, the traffic noise characteristics were evaluated in terms of vehicle types and pavement surface conditions.

• International Journal of Highway Engineering
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• v.12 no.4
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• pp.211-218
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• 2010

Volume of concrete slab changes by temperature and moisture effects. At that time, tensile stress develops because the slab volume change is restrained by friction resistance between the slab and subbase, and then crack occurs occasionally. Accordingly, researchers have made efforts to figure out the friction characteristics between the slab and subbase by performing push-off tests. Lately, researches to analyze concrete pavement behavior by the friction characteristics have been performed by finite element method. In this study, The friction characteristics between the slab and subbase were investigated based on the friction test results for lean concrete, aggregate, and asphalt subase widely used in Korean concrete pavements. The energy method bilinearizing relation between nonlinear friction resistance and displacement were suggested. The friction test was modeled by 3-D finite element program, ABAQUS, and the model was verified by comparing the analyzed results to the test results. The bilinear model developed by the energy method was validated by comparing analysis results obtained by using the nonlinear and bilinear friction resistance displacement relation as input data. A typical Korean concrete pavement was modeled by ABAQUS and EverFE and analyzed results were compared to evaluate applicability of the bilinear model.

• Biomolecules & Therapeutics
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• v.24 no.4
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• pp.410-417
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• 2016

Quercetin is a flavonoid usually found in fruits and vegetables. Aside from its antioxidative effects, quercetin, like other flavonoids, has a various neuropharmacological actions. Quercetin-3-O-rhamnoside (Rham1), quercetin-3-O-rutinoside (Rutin), and quercetin-3-(2(G)-rhamnosylrutinoside (Rham2) are mono-, di-, and tri-glycosylated forms of quercetin, respectively. In a previous study, we showed that quercetin can enhance ${\alpha}7$ nicotinic acetylcholine receptor (${\alpha}7$ nAChR)-mediated ion currents. However, the role of the carbohydrates attached to quercetin in the regulation of ${\alpha}7$ nAChR channel activity has not been determined. In the present study, we investigated the effects of quercetin glycosides on the acetylcholine induced peak inward current ($I_{ACh}$) in Xenopus oocytes expressing the ${\alpha}7$ nAChR. $I_{ACh}$ was measured with a two-electrode voltage clamp technique. In oocytes injected with ${\alpha}7$ nAChR copy RNA, quercetin enhanced $I_{ACh}$, whereas quercetin glycosides inhibited $I_{ACh}$. Quercetin glycosides mediated an inhibition of $I_{ACh}$, which increased when they were pre-applied and the inhibitory effects were concentration dependent. The order of $I_{ACh}$ inhibition by quercetin glycosides was Rutin${\geq}$Rham1>Rham2. Quercetin glycosides-mediated $I_{ACh}$ enhancement was not affected by ACh concentration and appeared voltage-independent. Furthermore, quercetin-mediated $I_{ACh}$ inhibition can be attenuated when quercetin is co-applied with Rham1 and Rutin, indicating that quercetin glycosides could interfere with quercetin-mediated ${\alpha}7$ nAChR regulation and that the number of carbohydrates in the quercetin glycoside plays a key role in the interruption of quercetin action. These results show that quercetin and quercetin glycosides regulate the ${\alpha}7$ nAChR in a differential manner.

• Journal of Korea Water Resources Association
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• v.32 no.1
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• pp.71-81
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• 1999

The objective of this study is to develop a model which can design an optimal pipe network system of least cost while satisfying all the design constraints including hydraulic constraints using a genetic algorithm technique. Hydraulic constraints interfaced with the simulation program(KYPIPE) checked feasible solution region. Genetic algorithm(GA) technique is a relatively new optimization technique. The GA is known as a very powerful search and optimization technique especially when solving nonlinear programming problems. The model developed in this study selects optimal pipe diameters in the form of commercial discrete sizes using the pipe diameters and the pumping powers as decision variables. The model not only determines the optimal diameters and pumping powers of pipe network system but also satisfies the discharge and pressure requirements at demanding nodes. The model has been applied to an imaginary and an existing pipe network systems. One system is adopted from journal papers which has been used as an example network by many other researchers. Comparison of the results shows compatibility of the model developed in this study. The model is also applied to a system in Goyang city in order to check the model applicability to finding of optimal pumping powers. It has been found that the developed model can be successfully applied to optimal design of pipe network systems in a relatively simple manner.

• Journal of Korea Water Resources Association
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• v.33 no.2
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• pp.145-157
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• 2000

The Water Quality Analysis Simulation Program 5 (WASP5) and HEC-2 models have been coupled and applied to find the possibility of simulation of long-term river water quality variation. The EUTR05 as a simulator of water quality simulation in WASPS model was used to simulate the water quality variables in the downstream of Geum-River from Daechung multi-purpose dam during the dry period. The water quality and flow rate conditions have been measured at the stage measurement stations located in the downstream of Geum-River from Daechung dam in December, 1998 and January and March, 1999. The water quality simulation model was calibrated with January data of 1999, and verified with December data of 1998 and March data of 1999. The trend of longitudinal variation of water quality variables simulated by model is consistent with that of measured water quality constituents except chlorophyll-a, $BOD_5,\;NH_3-N\;and\;PO_4-P$ simulated with March data of 1999. Furthennore, the chlorophyll a concentration in the mainstream of Geum-River was simulated by changing the concentrations of $PO_4-P$ and/or $NH_4-N$ flowing into the mainstream of Geum-River from Gabcheon and Mihocheon. The variation of chlorophyll a concentration in the mainstream was almost ignorable except only when $NH_3-N\;and\;PO_4-P$ concentrations decreased by 70% flow into the mainstream from Gabcheon and Mihocheon.

• Journal of Korea Water Resources Association
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• v.45 no.5
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• pp.495-503
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• 2012

It is necessary to perform the precise analysis of unsteady flow for effective design of the side-weir detention basin installed in the river. Generally, the HEC-RAS program, which is a 1D unsteady numerical model, is mostly used to simulate the unsteady flow for rivers. However, it is difficult to have confidence of unsteady flow results simulated by HEC-RAS due to the lack of experimental data and field monitoring data for the channel with a side-weir detention basin. Therefore, the purpose of this study is to validate or verify the simulation results calculated by HEC-RAS through the experiments for the open channel with a side-weir detention basin using specially-designed unsteady discharge-supply system. The experimental cases included unsteady flows in the straight channel with and without a side-weir detention basin. Especially, for the case with a detention basin, the experiment was performed to consider only the free flow condition over the side-weir. The study results showed that values of water level and discharge obtained from HEC-RAS coincided reasonably with experimental results with the maximum error of 3% for water level and 1% for discharge in the case of the flow without the side-weir detention basin and 4% for water level and 2% for discharge with the side-weir detention basin.

• Journal of Microbiology
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• v.44 no.1
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• pp.64-71
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• 2006

To investigate the effects of the nucleotide sequences in Shine-Dalgarno (SD) and the spacer region (SD-ATG) on bovine growth hormone (bGH) gene expression, the expression vectors under the control of the T7 promoter (pT7-7 vector) were constructed using bGH derivatives (bGH1 & bGH14) which have different 5'-coding regions and were induced in E. coli BL21 (DE3). Oligonucleotides containing random SD sequences and a spacer region were chemically synthesized and the distance between the SD region and the initiation codon were fixed to nine bases in length. The oligonucleotides were annealed and fused to the bGH1 and bGH14 cDNA, respectively. When the bGH gene was induced with IPTG in E. coli BL21(DE3), some clones containing only bGH14 cDNA produced considerable levels of bGH in the range of $6.9\%\;to\;8.5\%$ of total cell proteins by SDS-PAGE and Western blot. Otherwise, the bGH was not detected in any clones with bGH1 cDNA. Accordingly, the nucleotide sequences of SD and the spacer region affect on bGH expression indicates that the sequences sufficiently destabilize the mRNA secondary structure of the bGH14 gene. When the free energy was calculated from the transcription initiation site to the +51 nucleotide of bGH cDNA using a program of nucleic acid folding and hybridization prediction, the constructs with values below -26.3 kcal/mole (toward minus direction) were not expressed. The constructs with the original sequence of bGH cDNA also did not show any expression, regardless of the free energy values. Thus, the disruption of the mRNA secondary structure may be a major factor regulating bGH expression in the translation initiation process. Accordingly, the first stem-loop among two secondary structures present in the 5'-end region of the bGH gene should be disrupted for the effective expression of bGH.

• Journal of Energy Engineering
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• v.13 no.1
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• pp.51-59
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• 2004

The NSSS (Nuclear Steam Supply System) thermal-hydraulic programs adopted in the domestic full-scope power plant simulators were provided in early 1980s by foreign vendors. Because of limited compulsational capability at that time, they usually used very simplified physical models for a real-time simulation of NSSS thermal-hydraulic transients, which entails inaccurate results and, thus, the possibility of so-called "negative training", especially for complicated two-phase flows in the reactor coolant system. In resolve the problem, KEPRI developed a realistic NSSS T/H program ARTS which was based on the RETRAN-3D code for the improvement of the Nuclear Power Plant full-scope simulator. The ARTS (based on the RETRAN-3D code) guarantees the real-time calculations of almost all transients and ensures the robustness of simulations. However, there is some possibility of failing to calculate in the case of large break loss of coolant accident (LBLOCA) and low-pressure low-flow transient. In this case, the backup calculation system cover automatically the ARTS. The backup calculation system was expected to provide substantially more accurate predictions in the analysis of the system transients involving LBLOCA. The results were reasonable in terms of accuracy, real-time simulation, robustness and education of operators, complying with FSAR and the AMSI/ANS-3.5-1998 simulator software performance criteria.

• Journal of the Korean Institute of Landscape Architecture
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• v.37 no.6
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• pp.39-47
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• 2010

The coastal area is the place where two conflicting values provide opportunities for recreation, tourism and conservation of the natural environment. Most of these coastal areas have been disregarded in terms of tourism because of the high value placed on natural resources. Management strategy has usually been first on the priority list of natural. resources. However, due to the significant number of visitors, the Important-Satisfaction Analysis(ISA) was applied as a mean of complement since the 1970s. This study analyzed the difference between visitor satisfaction and the importance of the main management strategy targeting visitors to Sun-cheon Bay Ecological Park on weekdays and weekends. Results show that Sun-cheon Bay Ecological Park and the city government have paid a lot of attention and invested a lot of money, but efficiency of publicity didn't come up to their afford. Therefore, we should prepare information facilities, public education facilities and human power. Also needed are visitors' temporal-spacial control to set specific programs and a guide for information education control. It means visitors' company forms change depends on weekday and weekend. In addition, a breeding space for birds should be built for observation, education and exhibition to help meet visitor expectations. Visitors' positive satisfaction might be provided in establishing strategy as a very important measure in limited area. In conclusion, this study might be provided as preliminary data when the management strategy and related guidelines are established through the management priority of coastal regions where importance and satisfaction conflict.