• International Journal of Highway Engineering
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• v.18 no.6
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• pp.1-10
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• 2016

OBJECTIVES : Currently, the market for carbon emissions trading has been increasing. In Korea, it is known that traffic mode rate in bike transportation is low. However, if bike transportation system is encouraged and the traffic mode rate is increased, it would be possible to reduce carbon emissions through the trading market. In this study, a practical policy to activate the bike transportation system in Korea will be proposed and verified. METHODS : Past studies regarding bike transportation system in international and domestic metropolitan cities were analyzed. Moreover, detailed reviews on recent carbon emissions trading market were performed. In particular, SWOT analysis on the bike transportation system in Korea and policy topology analysis were conducted. RESULTS : Based on the literature reviews and SWOT analysis, a new bike transportation policy was proposed. Several actual plans to adopt in Korea were proposed. In addition, a new bike transportation policy was analyzed using policy typology model, and a business model related to the cost of implementing the system and CERs were also proposed. CONCLUSIONS : It is concluded that the proposed bike transportation activation policy and several practical plans to connect CERs and a business model including bus, subway, T-money and bike riders to give some incentive were effective and reasonable. It is desired that this study will help Korea to get CERs through bike transportation activation in the future.

• Biomolecules & Therapeutics
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• v.15 no.3
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• pp.192-198
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• 2007

Emodin (1,3,8-trihydroxy-6-methylanthraquinone) is a major constituent of rhubarb. Although it has been claimed to have a wild spectrum of therapeutic value, its side effects, especially in human kidney cells have not been well characterized. In this study, we have carried out in vitro genetic toxicity test of emodin and microarray analysis of differentially expressed genes in response to emodin. The result of Ames test showed mutations with emodin treatment in base substitution strain TA1535 both with and without exogenous metabolic activation. Likewise, emodin showed mutations in frame shift TA98 both with and without exogenous metabolic activation. The result of COMET assay in L5178Y cells with emodin treatment showed DNA damage both with and without exogenous metabolic activation. Emodin did not increase micronuclei in CHO cells both with and without exogenous metabolic activation. 150 Genes were selected as differentially expressed genes in response to emodin by microarray analysis and these genes would be candidate biomarkers of genetic toxic action of emodin.

• Biomolecules & Therapeutics
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• v.15 no.3
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• pp.199-204
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• 2007

Carbamates have excellent insecticidal activities against a broad spectrum of insects. They possess knocking-down, fast-killing, and systemic effects, however, they are toxic to mammals. In this study, we have carried out in vitro genetic toxicity test of methylcarbamate and microarray analysis of differentially expressed genes in response to methylcarbamate. Methylcarbamate did not show mutations in base substitution strain TA1535 both with and without exogenous metabolic activation. Methylcarbamate did not show mutations in frame shift TA98 both with and without exogenous metabolic activation. Methylcarbamate showed DNA damage based on single cell gel/comet assay in L5178Y cells both with and without exogenous metabolic activation. Methylcarbamate did not increase micronuclei in CHO cells both with and without exogenous metabolic activation. Microarray analysis of gene expression profiles in L5178Y cells in response to methylcarbamate selected differentially expressed 132 genes that could be candidate biomarkers of genetic toxic action of methylcarbamate.

• Journal of the Korean Wood Science and Technology
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• v.29 no.3
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• pp.59-67
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• 2001

Rice husk flours were analyzed by chemical composition and thermogravimetric methods in nitrogen atmosphere to discuss its feasibility as a raw material for manufacturing agricultural lignocellulosic fiber-thermoplastic polymer composite. It was revealed in the chemical composition analysis that rice husk flour was composed of moisture, 5.0%; lignin, 21.6%; holocellulose, 60.8%; ash, 12.6%. In the thermogravimetric analysis (TGA), thermal decomposition behavior of rice husk flour from room temperature to $350^{\circ}C$ was similar to that of wood flour, but rice husk flour was more thermally stable from 350 to $800^{\circ}C$ than wood flour because of higher silica content in the rice husk flour and smaller particle size of rice husk flour. The activation energy of thermal decomposition was evaluated using Flynn & Wall expression. As the thermal decomposition proceeded in rice husk flour, the activation energy of thermal decomposition appeared almost constant up to ${\alpha}=0.25$, but thereafter increased. Activation energy of thermal decomposition in wood flour, however, decreased steeply up to ${\alpha}=0.3$, but thereafter remained almost constant. From the results, rice husk flour was thought be a substitute for wood flour in manufacturing agricultural lignocellulosic fiber-thermoplastic polymer composite in the aspect of thermal decomposition.

• Biomolecules & Therapeutics
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• v.14 no.4
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• pp.246-252
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• 2006

1,2-Dibromoethane(DBE) has been widely used as a soil fumigant, an additive to leaded gasoline and an industrial solvent. In this study, we have carried out in vitro genetic toxicity test of 1,2-dibromoethane and microarray analysis of differentially expressed genes in response to 1,2-dibromoethane. 1,2-Dibromoethane showed mutations in base substitution strain TA1535 both with and without exogenous metabolic activation. 1,2-Dibromoethane showed mutations in frame shift TA98 both with and without exogenous metabolic activation. 1,2-Dibromoethane showed DNA damage based on single cell gel/comet assay in L5178Y cells both with and without exogenous metabolic activation. 1,2-Dibromoethane increased micronuclei in CRO cells both with and without exogenous metabolic activation. Microarray analysis of gene expression profiles in L5178Y cells in response to 1,2-dibromoethane selected differentially expressed 241 genes that would be candidate biomarkers of genetic toxic action of 1,2-dibromoethane.

• Nuclear Engineering and Technology
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• v.34 no.1
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• pp.30-41
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• 2002

The neutron beam is fully characterized for the prompt gamma activation analysis facility at Hanaro in the Korea Atomic Energy Research Institute(KAERI). The facility uses thermal neutrons which are diffracted vertically from a horizontal beam port by a set of pyrolytic graphite(PG) crystals positioned at the Bragg angle of 45" Neutron spectra, neutron flux and Cd-ratio are determined for the three extraction modes of diffracted beam by means of the theoretical and experimental efforts. To obtain theoretical result, the reflectivity of pyrolytic graphite is calculated in the diffraction model for mosaic crystal and the angular divergence after diffraction by mosaic crystal is estimated from Monte Carlo simulation. The time-of-flight spectrometer and gold activation wire are used for measuring the neutron spectra. Both the calculated and measured spectra have proven that the unique feature of polychromatic beam obtained by PG crystals are useful for PGAA. The thermal neutron flux of 7.9$\times$107 n/cm$^2$s and the Cd-ratio of 266 for gold have been achieved at the sample position while the reactor operates at 24 MW The uniformity of beam flux is 12% in the central 1$\times$1 cm$^2$ area. Finally, the beam is briefly characterized by the effective velocity and temperature which are determined by measuring the prompt Y-ray spectra for thin and thick boron samples.ples.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.5
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• pp.506-517
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• 2000

In distributed real-time system, a task activated by the completion of its preceding task can be modeled as a periodic task with activation jitter. An activation jitter of a task is defined asthe difference between the worst case and the best case response time of its preceding task. Becausethe existing approaches assume that the best case response time is much smaller than the actual one,the activation jitter and the worst case response time of lower priority tasks are overestimated. Thispaper proposes a new analysis technique to calculate the best case response time more precisely andto reduce the activation jitter bounds. The proposed technique obtains the best case response time byconsidering the relative phase between tasks. The precise analysis of the activation jitters can reducethe worst case response time of other tasks and increase the schedulability. The simulation resultsshow that the proposed analysis technique improves the accuracy of the best case and the worst caseresponse time up to 40% and 6%, respectively.

• Applied Chemistry for Engineering
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• v.29 no.3
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• pp.318-324
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• 2018

In this study, PAN (polyacrylonitrile) based activated carbon fibers were prepared by water vapor activation method which is a physical activation method. Activation was performed with temperature and time as parameters. When the activation temperature reached 700, 750 and $800^{\circ}C$, the activation was carried out under the condition of a water vapor flow rate of 200 ml/min. In order to analyze the pore structure of activated carbon fibers, the specific surface area ($S_{BET}$) was measured by the adsorption/desorption isotherm of nitrogen gas and AFM analysis was performed for the surface analysis. Tensile tests were also conducted to investigate the effect of the pore structure on mechanical properties of fibers. As a result, the $S_{BET}$ of fibers after the activation showed a value of $448{\sim}902m^2/g$, the tensile strength decreased 58.16~84.92% and the tensile modulus decreased to 69.81~83.89%.

• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.10-18
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• 2010

This paper presents a optimization of sigmoid activation function parameter using genetic algorithms and pattern recognition analysis in input space of two spirals benchmark problem. To experiment, cascade correlation learning algorithm is used. In the first experiment, normal sigmoid activation function is used to analyze the pattern classification in input space of the two spirals problem. In the second experiment, sigmoid activation functions using different fixed values of the parameters are composed of 8 pools. In the third experiment, displacement of the sigmoid function to determine the value of the three parameters is obtained using genetic algorithms. The parameter values applied to the sigmoid activation functions for candidate neurons are used. To evaluate the performance of these algorithms, each step of the training input pattern classification shows the shape of the two spirals.

• Journal of Electrochemical Science and Technology
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• v.2 no.3
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• pp.131-135
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• 2011

It is, in general, believed that during the activation process, the proton conductivity increases due to wetting effect and the electrochemical resistance reduction, resulting in an increase in the fuel cell performance with time. However, until now, very scant information is available on the understanding of activation processes. In this study, dominant variables that effect on the performance increase of membrane electrode assemblies (MEAs) during the activation process were investigated. Wetting, pore restructuring and active metal utilization were analyzed systematically. Unexpectedly, the changes for both ohmic and reaction resistance characterized by the electrochemical impedance spectroscopy (EIS) after initial wetting process were much smaller when considering the degree of cell performance increases. However, the EIS spectra represents that the pore opening of electrode turns into gas transportable structure more easily. The increase in the performance with activation cycles was also investigated in a view of active metals. Though the particle size was grown, the number of effective active sites might be exposed more. The impurity removal and catalytic activity enhancement measured by cyclic voltammetry (CV) could be a strong evident. The results and analysis revealed that, not merely wetting of membrane but also restructuring of electrodeand catalytic activity increase are important factors for the fast and efficient activation of the polymer electrolyte fuel cells.