• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.05a
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• pp.262-268
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• 2003

Organic coatings are widely used to control the corrosion of steel structure. The water in coatings may cause swelling or solvation of coatings, leading to the degradation of coatings. In addition, water affects the permeation of oxygen and other corrosive agents, and consequently the presence of such substances at coating-metal interface promotes corrosion of metal substrate. In this study, the anticorrosive properties of 4 types of coating, such as epoxy-epoxy, epoxy-urethane, urethane-epoxy, urethane-urethane, were evaluated. The evaluation tests were carried out under cyclic water-absorption/desorption conditions, consisting of alternative exposure to diluted 0.001M-LiCl($a_{1120}{\fallingdotseq}1$) and concentrated l0M-LiCl($a_{1120}{\fallingdotseq}0.05$). The anticorrosive performances of coatings were found to decrease in the order of urethane-urethane> urethane-epoxy> epoxy-epoxy coating.

• Journal of Digital Convergence
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• v.13 no.12
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• pp.151-160
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• 2015

As a lexical meaning, casino is defined as "a certified gambling house, equipped with recreational facilities such as dance and music, etc., where people play roulette or cards." Casinos started from 17th to 18th century for European nobility and their social meetings and established a casino industry framework in the United States in the 1930s. The success of the casino business leads to the increase of sales; it became very helpful for the local and national government revenues and also for the related incidental tasks. Casino operations include a variety of fields, such as general customer management, dealer game management, security, account management, currency exchange, re-exchange management, marketing management, comp management and placement management, etc. These operations should be organically connected to each other by information systems such as a groupware, ERP and Customer Relationship Management (CRM), etc. In addition, in order to effectively manage comprehensive entertainment service, including accommodation and tourism, it is necessary to develop an information system which supports casino business and collateral entertainment service, collects the data generated throughout the business and provides information about the situations of management. Thus, this study will propose a casino information system designed and implemented, considering these details.

• The Journal of the Korea Contents Association
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• v.17 no.12
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• pp.180-190
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• 2017

This is Kangwon Land casino case due to the damages of betting money, which is likely to affect the contents industry in the future. The reason why the gambler and his family's suit is that why the manager did not control their own access or did not supervise the wagering rules. The provisions of the "Restriction on the amount of money to be paid to the casino" in the Article 14 of the Enforcement Decree of the Act on the Support for the Development of the Abandoned Mine Area are not intended to increase the duty of the casino managers. It is just one of many public regulations imposed. No matter what legislation is made for public interest, it can not be considered equally in the private duty. If so, too much effort will be required to enact or amend the public law and this makes the legislative activity impossible. The Act on the Restriction on Access to the Casino shall be construed accordingly. From the point of view of economic efficiency theory, if we overestimate statutory duties (liability for compensation) excessively, the price goes up on the market, and the volume of transaction decreases drastically. This reduces the economic utility of resources in the society as a whole (total output, foreign currency acquisition amount, etc.).

• Korean Journal of Environmental Biology
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• v.17 no.1
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• pp.1-9
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• 1999

Numerous observations revealed strong evidence of increased middle ultraviolet radiation or UV-B (280 ~ 320 nm) at the earth's surface resulting from stratospheric ozone depletion. UV is the waveband of electromagnetic radiation which is strongly absorbed by nucleic acids and proteins, thus causing damage to living systems. It has been recorded in the East Sea, Korea that solar UV-B impinging on the ocean surface penetrates seawater to significant depths. Recent researches showed that exposure to UV-B for as short as 2h at the ambient level (2.0 Wm$^{-2}$) decreased macroalgal growth and photosynthesis and destroyed photosynthetic pigments. These may suggest that UV-B could be an important environmental factor to determine algal survival and distribution. Some adaptive mechanisms to protect macroalgae from UV-damage have been found, which include photoreactivation and formation of UV-absorbing pigments. Post-illumination of visible light mitigated UV-induced damage in laminarian young sporophytes with blue the most effective waveband. The existence of UV-B absorbing pigments has been recognized in the green alga, Ulva pertusa and the red alga, Pachymeniopsis sp., which is likely to exert protective function for photosynthetic pigments inside the thalli from UV-damage. Further studies are however needed to confirm that these mechanisms are of general occurrence in seaweeds. Macroalgae together with phytoplankton are the primary producers to incorporate about 100 Gt of carbons per year, and provide half of the total biomass on the earth. UV-driven reduction in macroalgal biomass, if any, would therefore cause deleterious effects on marine ecosystem. The ultimate impacts of increasing UV-B flux due to ozone destruction are still unknown, but the impression from UV studies made so far seems to highlight the importance of setting up long-term monitoring system for us to be able to predict and detect the onset of large -scale deterioration in aquatic ecosystem.

• Journal of Conservation Science
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• v.29 no.4
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• pp.395-406
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• 2013

The conservation of damaged object should be restored by the similar material with the original and they have to reversibility as possible as. The characteristics of Buddhist mural paintings composed of clay are with soft material. So far, there have been a number of researches done on filling material that reinforces cracks and exfoliation of mural painting. Based on the application of traditional materials, it was found that they are appropriate to various applications. However, only based on those research results, there are some constraints to the application in the field. In addition, there has been only a few researches done on physical characteristics of filling materials. A major issue is that there is not any standard established on various mixing ratio, which is required for treatment of mural painting. This study was carried out to understand the physical characteristics of filling materials on clay mural painting. The 1st test was conducted to analyze test specimen in twelve different conditions by varying soil mixing ratio and organic medium. The 2nd test was conducted to manufacture filling materials appropriate to the mural painting, based on the result of stable condition from the 1st test, and which was applied to treatment in field.

• Journal of Applied Biological Chemistry
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• v.64 no.3
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• pp.217-223
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• 2021

5-aminolevulinic acid (ALA) is a representative photosensitizer used in numerous fields including cancer diagnosis and treatment. In this study, experiments were conducted to optimize the growth of Rhodobacter sphaeroides and production of ALA through LED irradiation of various wavelengths, addition of organic acid precursors of ALA, and changes in glucose concentration. After 72 h cultivation, the 850 nm wavelength LED irradiated at the same light intensity as the incandescent lamp increased the growth of R. sphaeroides and the production of ALA about 1.5- and 1.8-fold as compared with the control, respectively (p <0.0001 and p <0.0001). As a result of culturing R. sphaeroides by irradiating an LED with a wavelength of 850 nm after adding organic acid to the final concentration of 5 mM in culture medium, the production of ALA was increased about 2.8-fold in medium supplemented with pyruvic acid compared with the control (p <0.0001). In addition, the growth of the strain and the production of ALA were increased about 2.9- and 3.4-fold in medium supplemented with 40 mM glucose compared to the control which added only 5 mM pyruvic acid, respectively (p <0.0001 and p <0.0001). The yield of ALA per cell dry mass was about 1.4 folds higher than that of the control in 20 and 40 mM glucose, respectively (p <0.001). In conclusion, the growth of R. sphaeroides and production of ALA were increased by 850 nm wavelength LED irradiation. It also optimized the growth of R. sphaeroides and production of ALA through organic acid addition and glucose concentration changes.