• Macromolecular Research
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• v.11 no.6
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• pp.444-450
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• 2003

Hydrophobically End-capped polyethylene oxide Urethane Resin(HEUR)-associating polymers, HEUR 35(8), HEUR 35(12), and HEUR 35(18), comprise a polyethylene oxide (PEO) having a molecular weight of 35,000 that is end capped with two C$\_$8/H$\_$17/, C$\_$12/H$\_$25/, and C$\_$18/H$\_$37/ alkyl chains, respectively. These associating polymers were synthesized by condensation reactions with polyethylene oxides and alkyl isocyanates. The self-diffusion coefficients of HEUR-associating polymers were measured in aqueous solution by pulsed-gradient spin-echo (PGSE) nuclear magnetic resonance (NMR) spectroscopy. All polymers underwent a decrease in their mean diffusion coefficients as the concentration was increased. However, the dispersion of the diffusion coefficients, ${\beta}$, about the mean fluctuated with changes in concentration. The large dispersion at low concentrations of HEUR 35(8) and HEUR 35(12) is related to the interaction between hydrophobic end groups, and the large dispersion at high concentrations of HEUR 35(18) is correlated with transient network formation. These results are valuable for predicting the associating mechanism of the large aggregates before and after their critical micelle concentration.

• Bulletin of the Korean Chemical Society
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• v.21 no.6
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• pp.623-627
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• 2000

Aggregation of hydrophobically end-capped poly(ethylene oxide)s: HEURs, denoted as $C_8$$EO_{380}$$C_8$, $C_12$$CO_{600}$$C_{12}$, and $C_{18}$$EO_{860}$$C_{18}$,are described using static fluorescence, dynamic light scattering, and atomic force microscope (AFM) techniques. The CAC (critical aggregation concentration) was determined by com-paring two fluorescent peaks which were influenced by the polarity of the probe dye molecules, pyrene. The aggregation occurs in concentrations higher than 10 g/L of $C_8$$EO_{380}$$C_8$ and the CAC decreases by increasing the side chain length. The dynamic light scattering experiment shows fast mode and slow mode decays, and both are diffusive. The fast mode does not depend on the concentration, but the slow mode shows concentration dependence influenced by the formation of an aggregated structure. The hydrophobic end groups effect more dominantly than the main chains for the formation of HEUR micelles. By increasing the concentration, the HEUR micelles change their structure from spheres to rodlike micelles, and finally make fused structures, which were visualized with atomic force microscopy.

• Journal of the Korean Chemical Society
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• v.37 no.4
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• pp.416-422
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• 1993

As a result of adsorbing phthalocyanine (metal free, ${\alpha}\;and\;{\beta}$-Cu) on zinc oxide in aqueous solution using nonionic surfactant, all of the added dye was adsorbed and Na salt of sulfonated phthalocyanine showed the Langmuir monolayer adsorption. To analyze the effect of adsorption on zinc oxide, photovoltage was measured using surface photovoltmeter. The high photovoltaic effect was observed at intrinsic wavelength of zinc oxide and wavelength of adsorbed phthalocyanine dye. Metal free phthalocyanine, ${\alpha}$-copper phthalocyanine and ${\beta}$-copper phthalocyanine showed the highest photovoltaic effect when the percentage of coverage (${\theta}_{BET}$) for zinc oxide is about 80, while sulfonated phthalocyanine showed the highest photovoltaic effect when the percentage of coverage for zinc oxide is about 30.

• The Journal of the Korea Contents Association
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• v.22 no.2
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• pp.514-528
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• 2022

This study attempted to understand the characteristics of foreign direct investment by Chinese companies from the perspective of Dunning's OLI paradigm. This development of OFDI by Chinese companies was influenced by the Chinese government's policy, internal factors of the Chinese economy, and the economic and institutional environment of the investment target country. The characteristic of Chinese companies' OFDI is that investment in developed countries is gradually increasing amid regional concentration in Asia. And the proportion of tertiary industries is high, In the meantime, the structure of the secondary industry is changing. In addition, Chinese companies are gradually expanding and showing characteristics by considering the economic and political factors of the investment target country in the selection of overseas investment areas, and then selecting areas with little cultural difference from China's system. This characteristic of OFDI by Chinese companies is basically evaluated to be in line with the OLI paradigm of Dunning. However, the difference is that Chinese companies' OFDI not only advances in overseas investment using the strengths of companies, but also advances in investment to compensate for their shortcomings.

• The Journal of the Korea Contents Association
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• v.22 no.9
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• pp.283-297
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• 2022

This study analyzed to strategy and structure of outward foreign direct investment(OFDI) by Chinese Enterprises in 'one belt, one load' countries along the line from the perspective of Dunning's OLI paradigm. Chinese enterprises' investment in 'one belt, one road' countries was largely promoted for two strategic purposes. One is an investment to secure energy resources due to the nature of resource holdings in 'one belt, one road' countries, and the other is a transfer investment to solve the problem of surplus facilities, a problem in China's domestic economy. Chinese enterprises' investments in these 'one belt, one road' countries is evaluated to have been made with Dunning's investment decision conditions in the OLI paradigm, namely, Ownership specific advantages, Location specific advantages, and Internalization specific advantages. only if there is a difference, investment country, investment method, and investment industry are different due to the structure of international relations, religious conflict and cultural heterogeneity, institutional investment environment of the region, and awareness of Chinese enterprises.

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.176-185
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• 1995

To improve photosensisitizing efficiency of ZnO/$H_2Pc(I)_x$ system, ZnO/$H_2Pc(I)_x$ system was dispersed in a typical photoconductive polymer of poly(9-vinylcarbazole)(PVCZ). The iodine dopant level(x) of ZnO/${\chi}-H_2Pc(I)_x$ is proportional to concentration of iodine, whereas x of ZnO/${\beta}-H_2Pc(I)_x$ decreased from the highest x=0.97 at more than $6.3{\times}10^{-3}$ M iodine solution. The Raman spectra of ZnO/${\chi}-H_2Pc(I)_x$ at 514 nm exhibited characteristic $I_3^-$ patterns in the range of 50∼550 $cm^{-1}$ at $x{\geq}0.57.$ The surface photovoltage of ZnO/${\chi}-H_2Pc(I)_{0.48}$/PVCZ was approximately 1.6 times greater than ZnO/${\chi}-H_2 Pc(I)_{0.48}$ and was 1.8 times of ZnO/${\chi}-H_2Pc(I)_{0.57}$/PVCZ at 670 nm. With ZnO/$H_2Pc(I)_x$/PVCZ, the highest iodine dopant levels showed a higher photovoltage. Therefore the injection of holes from H2Pc into PVCZ resulted in that photosensisitizing effect of ZnO/$H_2Pc(I)_x$/PVCZ system was improved compared to ZnO/$H_2Pc(I)_x$ case.

• Journal of the Korea institute for structural maintenance and inspection
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• v.19 no.1
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• pp.23-34
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• 2015

Recently a new damper system with Kogome truss structure was developed and its mechanical properties were verified based on the laboratory test. This paper presents a Kagome truss damper external connection method for seismic strengthening of RC frame structural system. The Kagome external connection method, proposed in this study, consisted of building structure, Kagome damper and support system. The method is capable of reducing earthquake energy on the basis of the dynamic interaction between external support and building structures using Kagome damper. The pseudo-dynamic test, designed using a existing RC frame apartment for pilot application of LH corporation, was carried out in order to verify the seismic strengthening effects of the proposed method in terms of the maximum load carrying capacity and response ductility. Test results revealed that the proposed Kagome damper method installed in RC frame enhanced conspicuously the strength and displacement capacities, and the method can resist markedly under the large scaled earthquake intensity level.

• The Journal of the Korea Contents Association
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• v.19 no.11
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• pp.297-313
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• 2019

China's 'One Belt and One Load' is a national development strategy that aims to develop China and Eurasian Economic Area into a single economic Area by overland and sea routes. Thus, China's 'One Belt and One Load' construction will be a new engine for China and global economic development. At the same time, expected to have a significant impact on the international economic order and the enhancement the status of the Chinese economy. First of all, 'One Belt and One Load' will contribute to China's social stability by reducing the development gap between the East and West regions to some extent, as well as solving the problems of overcapacity and overproduction in China. Moreover, with a stable supply of energy resources, it will also contribute to the stable development of the Chinese economy. China's 'One Belt and One Load' will also enhance China's status by enhancing the level of Chinese influence and RMB in the international economy, in addition to the economic development of China and 'One Belt and One Load' consecutive countries. In particular, it will weaken the influence of the US, which has dominated the hegemony in the international community. Therefore, Korea, which maintains close economic relations with China, needs to prepare for countermeasures by closely monitoring the change in China's status as a result of China's 'One Belt and One Load' construction.

• The Journal of the Korea Contents Association
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• v.19 no.7
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• pp.335-347
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• 2019

China's 'One Belt and One Load' initiative is a mega-infrastructure project that connects China and the Eurasian Economies Area by overland and sea routes. Therefore, if it goes smoothly, It will be a new engine for economic development in China and the world, and It is expected to be a factor that will change the structure of the international economy. Especially, the Eurasian continent is likely to develop into the center of the global economy. But China's 'One Belt and One Load' initiative is not only macro and long-term, but also implies complexity, making it hard to be optimistic about development. China's 'One Belt and One Load' initiative is not only strongly promoted as a long-term national development strategy to be completed by 2049, but also strong economic complementarity between China and 'One Belt and One Load' consecutive countries. And many of the successive countries are expecting 'One Belt and One Load' construction. Therefore, there is no possibility at all. In particular, the possibility of development can not be completely ruled out, given the various policies of 'One Belt and One Load' currently being pursued by China. Even if it doesn't go smoothly, the process alone will have significant economic effects on China and neighboring countries, so it will be meaningful. With the help of information technology.

• Journal of the Korean Chemical Society
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• v.39 no.3
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• pp.163-175
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• 1995

Metal free phthalocyanine($H_2Pc$) partially doped with iodine, $H_2Pc(I)x$, has been made to improve photosensitizing efficiency of ZnO/$H_2Pc$. The content of iodine dopant level(x) for $H_2Pc(I)x$ upon $H_2Pc$ polymorphs was characterized as ${\chi}-H_2Pc(I)_{0.92}$ and ${\beta}-H_2Pc(I)_{0.96}$ by elemental analysis. Characterization of iodine-oxidized $H_2Pc$ were investigated by TGA (thermogravimetric analysis), UV-Vis, FT-IR, Raman and ESR (electron spin resonance) spectrum, and the adsorption properties of $H_2Pc(I)x$ on ZnO were characterized by means of Raman and ESR studies. TGA for $H_2Pc(I)x$ showed a complete loss of iodine at approximately 265$^{\circ}C$ and the Raman spectrum of $H_2Pc(I)x$ and ZnO/$H_2Pc(I)x$ at 514.5 nm showed characteristic $I_3^-$ patterns in the frequency region 90∼550 $cm^{-1}$. ZnO/$H_2Pc(I)x$ exhibited a very intense and narrow ESR signal at $g=2.0025{\pm}0.0005$ compared to $H_2Pc$/ZnO. Iodine doped ZnO/$H_2Pc(I)x$ showed a better photosensitivity compared to iodine undoped ZnO/$H_2Pc$. That is, the surface photovoltage of ${\chi}-H_2Pc(I)_{0.92}$/ZnO was approximately 31 times greater than that of ZnO/${\chi}-H_2Pc$ and ZnO/${\beta}-H_2Pc(I)_{0.96}$ was 5 times more efficient than ZnO/${\beta}-H_2Pc$ at 670 nm. And the dependence of photosensitizing effect upon $H_2Pc$ polymorphs was exhibited that the surface photovoltage of ZnO/${\chi}-H_2Pc(I)_{0.92}$ was approximately 5 times greater than ZnO/${\beta}-H_2Pc(I)_{0.96}$ at 670 nm. Therefore Iodine doping of H_2Pc$ resulted in increase in photoconductivity of $H_2Pc$ and photovoltaic effect of ZnO/$H_2Pc$ in the visible region.