• Bulletin of the Korean Chemical Society
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• v.14 no.6
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• pp.674-678
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• 1993

Di-and tri-peptides containing DL-N-hydroxyalanine were prepared. DL-N-Hydroxyalanine was linked, via its primary amino group, to the ${\alpha}$-carbon of glycine residues in dipeptide synthon (L-alanyl(${\alpha}$-DL-N-hydroxyalanyl)DL-glycine) 5, and tripeptide synthon (L-alanyl-L-alanyl(${\alpha}$-DL-N-hydroxyalanyl) DL-glycine) 12. 5 proved to be 19 times more potent than DL-N-hydroxyalanine when tested in vitro for the ability to inhibit the growth of E coli. However, 12 gave comparable potency to DL-N-hydroxyalanine itself.

• Proceedings of the Korea Contents Association Conference
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• 2019.05a
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• pp.179-180
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• 2019

Nowadays, clustering algorithm is considered as a promising solution for lacking human-labeled and massive data of social media sites in numerous machine learning tasks. Many researchers propose disaster event detection systems have ability to determine special local events, such as missing people, public transport damage by clustering similar tweets and hashtags together. In this paper, we try to extend tweet hashtag feature definition by applying word embedding. The experimental results are described that word embedding achieve better performance than the reference method.

• Journal of the Society of Disaster Information
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• v.18 no.3
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• pp.622-635
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• 2022

Purpose: Due to the change of demography, the ratio of senior drivers has increased and the transition to a super-aged society is expected to make more seniors drive in the future. Method: In this research, we analyzed medical characteristics of the driver's age-specific decline in body function and saw that both the function of the physical as well as mental capacities deteriorates as people age. Among them, various functions are precipitously weakened after reaching 70, implying that those over the age of 70 are classified as seniors in a medical sense. In this context, we also could identify that based on such age criteria, various safety policies for senior drivers should be developed and set up in Korea. Result: We could find a steep fall in the physical function of body after reaching 70 from the chronological change of cognitive function and judgment ability. In particular, it is revealed that the driving license institution and aptitude test for drivers over 70 should be thoroughly examined, as physical functions necessary for driving such as eyesight and hearing ability is not strong enough in many drivers over 70. Conclusion: Focusing on the physical capacity to drive, we tried to find the hazardous age bracket of senior drivers which might influence driving behaviors. Going forward, we expect this work would help to understand the policies for senior drivers and drivers' physical differences.

• KSBB Journal
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• v.8 no.4
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• pp.370-374
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• 1993

In transportation the amount of metal ion by crown ethers, dibenzo-18-crown-6 were investigated using ultraviolet spectrometer. Transported the amount of one valence metal ion as $K^+ and Li^+}$ was not so much. On the other hand, two valence metal ion increased by dibenzo-18-crown-6, which means that the ionic charge and hydration of two valence metal ion affected the carrying ability of crown ethers. The carrying ability of dibenzo-18-crown-6 was, therefore, adequate for two valence metal ion as $Ca^{2+}$ and $Ba^{2+}$. It was also suggested that transport metal ion by crown ethers, which is related rather the catching ability than the selectivity of metalion.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.20 no.1
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• pp.1-12
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• 2022

Bentonite is the most probable candidate to be used as a buffer in a deep geological repository with high swelling properties, hydraulic conductivity, thermal conductivity, and radionuclide sorption ability. Among them, the radionuclide sorption ability prevents or delays the transport of radionuclides into the nearby environment when an accident occurs and the radionuclide leaks from the canister, so it needs to be strengthened in terms of long-term disposal safety. Here, we proposed a surface modification method in which some inorganic additives were added to form NaP zeolite on the surface of the bentonite yielded at Yeonil, South Korea. We confirmed that the NaP zeolite was well-formed on the bentonite surface, which also increased the sorption efficiency of Cs and Sr from groundwater conditions. Both NaP and NaX zeolite can be produced and we have demonstrated that the generation mechanism of NaX and NaP is due to the number of homogeneous/heterogeneous nucleation sites and the number of nutrients supplied from an aluminosilicate gel during the surface modification process. This study showed the potential of surface modification on bentonite to enhance the safety of deep geological radioactive waste repository by improving the radionuclide sorption ability of bentonite.

• Korean Journal of Plant Tissue Culture
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• v.25 no.1
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• pp.7-11
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• 1998

Protoplasts were isolated from the parenchyma supension cultured cells of Streptanthus tortus using hydrolytic enzymes, 0.03% cellulase + 0.02% pectinase. Phloem cells and companion protoplasts were isolated from differentiated suspension cultured cells using hydrolytic enzymes, 0.2% macerase + 0.03% cellulase + 0.02% pectinase + 0.025% rohamet PC. Isolated parenchyma -and companion- protoplasts transported glucose into the cells, but not transported sucrose at all. On the other hand, isolated phloem cells transported sucrose into the cells actively, but not transported glucose. These results show for the first time that loading of sucrose into the phloem cells without nucleus was possible without contributing of companion cells and companion cells had not the ability to transport sucrose directly because of lack of sucrose carriers in the membrane. The sucrose transport into the isolated phloem cells depend on metabolic energy.

• Journal of Pharmaceutical Investigation
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• v.25 no.1
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• pp.55-62
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• 1995

W/O and O/W emulsions of tegafur (50 mg/5 ml/kg) were orally administered to rats to compare with their mesenteric lymphatic delivery effects. And also in order to demonstrate the lymph targeting associated to the oral route, it was deemed necessary to investigate the fate of solution after oral administration as a control. Lymph and plasma samples were periodically taken from each subject of mesenteric lymphatic duct cannulated rats. Then, lymph and plasma levels of tegafur and its active metabolite, 5-FU, were simultaneously observed. Also pharmacokinetic parameters were compared with each others. On the other hand, most previous studies of lymphatic transport have not addressed the question of whether an increase in mesenteric or thoracic lymph transport by the manipulation of a suspected variable was due to a selective delivery to the intestinal lymphatics or an overall increase availability. Therefore, based on a physiologically based pharmacokinetic model which represents the characteristics of lymphatic systems, we are also going to determine the contributions of mesenteric lymph transport versus thoracic lymph transport of tegafur reported in reference(13). In comparison with tegafur solution, AUC and mean residence time of plasma tegafur were significantly increased in W/O emulsion but significantly decreased in O/W emulsion. Lymph flow rates were similar in both solution and W/O emulsion but half in O/W emulsion. AUC of tegafur in mesenteric lymph and in plasma for W/O emulsion were 3.7 times and 2.9 times more than those for O/W emulsion, respectively. And AUC of 5-FU in thoracic lymph for W/O emulsion was 3.7 times more than that for O/W emulsion. These results suggested that lymphatic delivery or tegafur by W/O emulsion was more effective than that by on emulsion due to its differences or formation ability of chylomicrons.

• Journal of the Korean Chemical Society
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• v.38 no.2
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• pp.122-128
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• 1994

Macrocyclic ligand has been known to selectively bind with metal ions so that ability applied for the transport of metal ions across the emulsion liquid membrane in this study. The metal ions are transproted from the source phase to the receiving phase by the carrier of the organic phase. Several factors involved in the transport of metal ions acrose the emulsion membrane we reported here and these factors provided the informations for the selective seperation of some metal ion. Stability constants for cation-macrocyclic ligand and metal ion-anion receiving phase interaction are examined as parameters for the prediction of metal ion transport selectivities. $Pb^{2+}$ was transported higher rates than the other metal ions in the mixture solution. The interaction of metal ion to anion in receiving phase is important. $S_2O_3^{2-}$- in replacement of $NO_3^-$ in the receiving phase enhances the transport of $Pb^{2-}$since $Pb^{2-}-S_2O_3^{2-}$interaction is greater than $Pb^{2+}-NO_3^-$ interaction.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.41 no.3
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• pp.247-255
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• 2021

Individual passenger transfer information is not included in Seoul metropolitan subway Automatic Fare Collection (AFC) data. Currently, basic data such as travel time and distance are allocated based on the TagIn terminal ID data records of AFC data. As such, knowledge of the actual path taken by passengers is constrained by the fact that transfers are not applied, resulting in overestimation of the transport index. This research proposes a method by which a transit path that connects the TagIn and TagOut terminal IDs in AFC data is determined and applied to the transit index. The method embodies the concept that a passenger's line of travel also accounts for transfers, and can be applied to the transit index. The path selection model for the passenger calculates the line of transit based on travel time minimization, with in-vehicle time, transfer walking time, and vehicle intervals all incorporated into the travel time. Since the proposed method can take into account estimated passenger movement trajectories, transport-related data of each subway organization included in the trajectories can be accurately explained. The research results in a calculation of 1.47 times the values recorded, and this can be evaluated directly in its ability to better represent the transportation policy index.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.21 no.6
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• pp.299-310
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• 2022

The ability of an automated driving system is based on vehicle sensors, judgment and control algorithms, etc. The safety of automated driving system is highly related to the operational status of the road network and compliant road infrastructure. The safe operation of automated driving necessitates continuous monitoring to determine if the road and traffic conditions are suitable and safe. This paper presents a node and link system to build a road monitoring system by considering the ODD(Operational Design Domain) characteristics. Considering scalability, the design is based on the existing ITS standard node-link system, and a method for expressing the monitoring target as a node and a link is presented. We further present a technique to classify and manage hazard risk into five levels, and a method to utilize node and link information when searching for and controlling the optimal route. Furthermore, we introduce an example of system implementation based on the proposed node and link system for Sejong City.