• STI Policy Review
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• v.4 no.1
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• pp.1-13
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• 2013

The Schumpeterian process of "creative destruction", associated with the emergence and diffusion of new radical, so-called "general purpose" technologies, has throughout history impacted wealth and income, jobs creation, jobs displacement, and the emergence and submergence of new hotspots of innovation. Emerging countries have benefited most from such a renewing of those societies' dynamics, leading them to higher levels of economic development and welfare. Doing so they have shown a remarkable capacity in moving upstream in the value chain, from outsourcing of manufacturing activities to autonomous process technology development, product development, design, and applied research. At the same time however, such Schumpeterian processes have now and then turned into exactly opposite processes of "destructive creation." Such processes seem to have become common among what could be called "submerging" economies: innovation only benefitting a few at the expense of many with as a result an opposite pattern of a long term reduction in overall welfare, productivity, and employment growth.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.05a
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• pp.35-41
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• 2008

Qualitative enhancement of dwelling life has changing the recognition for the environment friendly wood which is being highlighted for its usage as an interior materials. This trend may prove the excellent performance of wood whose inherent characteristics has its comfortable, mild feeling of material, sound resistance and stabilities and the market of interior woods including floor, moulding and wooden panel as finishing interior materials is growing sustainably. However, since this materials is vulnerable to humidity and flame, waterproofing and flame retarding stability, an essential condition for interior materials, together with maintenance, are the main topics to be resolved. From the above-mentioned results, as a result of waterdrop contact angle, wood absorption volume and water content percentage test and the performance test of the processed materials after flame retardant, though there was some submerging time changes among types of woods for ensuring waterproofing performance improvement but as time passes, similar tendency was noticed to be formulated. As the submerging time is increased, so does the absorption volume and accordingly optimal level of range is judged to be drawn in order to ensure excellent performance, taking optimal economy into consideration. Therefore, it is considered that above-mentioned woods could be utilized for waterproof and flame retardant processed interior materials using uniform microwave and in order to put this technology into practical application, a research by way of diversified performance proving is required to be carried out.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.1
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• pp.49-54
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• 1999

An experiment was carried out using pots to investigate the effects of Chinese milk vetch on the seedling establishment and growth in rice. Four irrigations with five-day intervals and three different levels of vetch straw were investigated. Significantly higher panicle numbers were obtained in vetch-treated pots. Vetch levels were non-treatment as checks, vetch with top removed, root plus shoot 7.5 ton/ha, and root plus shoot 3.0 ton/ha. The time for complete degradation of vetch straws was reduced from 10 days to 5 days as submerged time was delayed, and was affected by the amount of mulched vetch straws. As the mulched vetch amount increased, the time for a complete degradation was extended from 4 days to 12 days. Grain yield and its components were significantly affected by irrigation time and mulched vetch amount. Effectively controlled, lowered reduction damage from the degrading vetch straw, irrigation date and vetch amount were the most important factors for the improving of seedling establishment in direct-sown rice.

• Journal of Korean Society of Water and Wastewater
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• v.21 no.4
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• pp.429-437
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• 2007

This study aims to develop a sulfur-using denitrification process which is possible a renovation to advanced treatment plant submerging a simple module in activated sludge aeration tank. At first, the impact factor of sulfur-using denitrification was appreciated by the batch test. Secondly, reflecting a dissolved oxygen effect of sulfur-using denitrification that was confirmed by the batch test, in a continuous nitrification/sulfur-using denitrification, high-rate nitrogen removal reaction was induced at optimum condition controlling DO concentration according to phases. Also, inside and outside of sulfur-using denitrification module was covered with microfilter and the module was considered as an alternative of clarifier. Result of batch test for sulfur-using denitrification, $NO_2{^-}N$ was lower for consumption of alkalinity and sulfur than that of $NO_3{^-}-N$. These results revealed the accordance of theoretical prediction. In continuous nitrification/sulfur-using denitrification experiment, actual wastewater was used as a influent, and influent nitrogen loading rates were increased 0.04, 0.07, 0.11, $0.14kg\;N/m^3-day$ by changing hydraulic retention times. At this time, nitrogen loading rates of packed sulfur were increased 0.23, 0.46, 0.69, $0.93kg\;N/m^3-day$. As a result, nitrification efficiency was about 100% and denitrification efficiency was 93, 81, 79, 72%. Accordingly, nitrogen removal was a high-rate. Also the module of sulfur-using denitrification covered with microfilter did not make a fouling phenomena according to increased flux. And the module was achieved effluent suspended solids of below 10 mg/L without a clarifier. In conclusion, it is possible a renovation to advanced treatment plant submerging a simple module packed sulfur in activated sludge aeration tank of traditional facilities. And the plant used the module packed sulfur is expected as a effective facilities of high-rate and the smallest.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.213-216
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• 2005

Salt attack and freezing & thawing test, one of the combined deterioration tests was performed to explore the mechanism of concrete structure deterioration under marine environment. Simple submerging test was proceeded to draw out its diffusion factor with salt water at the same time. Some of the mechanisms were driven with using three types of cements and four kinds of salt water concentrations. $\circ$ TBC was more durable than OPC or SRC for freezing and thawing action $\circ$ The higher chloride concentration of salt water was, the faster relative dynamic elastic modulus decreased and the higher the loss of weight was. $\circ$ The diffusion factor of TBC was smaller than those of TBC or SRC at simple submergence of concrete specimens into salt water.

• International Journal of Highway Engineering
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• v.4 no.4 s.14
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• pp.13-21
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• 2002

This study examines the importance of conditioning temperature and period before measuring fundamental properties of asphalt mixture. Marshall specimens were made and cured in the air for one day and conditioned by submerging at $60^{\circ}C$ water for 30 min before loading. It was observed that if the specimen was cured in a lower (or higher) than normal lab temperature ($25^{\circ}C$) before submerging, the measured values were not consistent. Indirect tensile strength (ITS) was also measured on the specimens cured at different temperatures. Although there is no regulation specifying how long the specimen should be conditioned before testing, it is recommended that the conditioning time be for the specimen to be at $25^{\circ}C$. Test must be conducted for the specimen cured well before conditioning for desired test. If curing temperature was lower or higher than normal, and mixture was not properly cured, then test results would not be reliable. This study showed how long the specimen should be submerged at $60^{\circ}C$ for Marshall test and conditioned at $25^{\circ}C$ for ITS test for the specimens cured in different temperature.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.9
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• pp.839-844
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• 2017

In the past few years, three-dimensional (3D) printing has been developed as a rapid prototyping (RP) technique. The fused deposition modeling (FDM)-type 3D printing is one of the most useful RP methods; however, it still has several disadvantages, such as low conductivity, heat degradation, and low surface quality. In this study, test specimens are fabricated using an FDM-type 3D printer with an ABS material. Then, the specimens undergo post-processing on submerging in acetone with various processing times. As the processing time increases, surface roughness is enhanced significantly within the first five seconds by chemical processing, following which the processing effects are reduced. Furthermore, post processing causes the ultimate strength and strain to increase slightly with increased processing time.

• International Journal of Highway Engineering
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• v.6 no.4 s.22
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• pp.45-53
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• 2004

This study dealt with correlation analysis between deformation strength and rut resistance of asphalt concretes based on binder grade in Superpave specification with changing submerging time. Currently, Mashall mix design is known to have little correlation with rutting related performance. Therefore, some agencies started to use the Superpave method for asphalt mix design. But this method has a weak point in that it can not distinct mechanical property of the asphalt mixtures designed. For solution of these problem, this study used deformation strength, $S_D$, of Kim test which is a new approach under development for finding property which represents rut resistance characteristics of asphalt mixtures under static loading. This study used two aggregates from two regions and five PG asphalt binders. Final rut depth (DR) and dynamic stability (DS) from wheel tracking (WT) test were obtained. and $S_D$ value of the same mixture specimen which was made by gyratory compactor was obtained using loading head [4(1.0)]. Three submerging times 30min, 40min, 50min were used as a test variable at $60^{\circ}C$. Correlation analysis of DR and DS with $S_D$ were performed based on PG grade. It was found out that the $S_D$ has a high correlation with DR and DS of superpave mixtures. The highest $R^2$ was found from the $S_D$ values of 30min. submerged specimen.

• Journal of Korean Society of Water and Wastewater
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• v.23 no.4
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• pp.439-446
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• 2009

This study was performed to evaluate SND(simultaneous nitrification and denitrification)efficiency, nitrogen removal efficiency and filtration function of non-woven fabric by using submerging MBR packed with granular sulfur covered with non-woven fabric filter. Synthetic wastewater was used as influent wastewater. Concentration of $NH_4{^+}-N$ in influent was maintained about 40 mg/L and the experiment was performed in four phases according to the flow rate. Nitrogen loading rate divided four phases ranging from $0.04 kg\;NH_4{^+}-N/m^3-day$ to $0.16 kg\;NH_4{^+}-N/m^3-day$. As a result, the maximum $NH_4{^+}-N$ removal rate was accomplished at $0.142 kg\;NH_4{^+}-N/m^3-day$ in nitrogen loading of $0.147 kg\;NH_4{^+}-N/m^3-day$. Nitrification efficiency was higher than 95% in all phases. $NO_3{^-}-N$ loading rate was adjusted ranging from $0.22 kg\;NO_3{^-}-N/m^3-day$ to $0.89 kg\;NO_3{^-}-N/m^3-day$. The maximum $NO_3{^-}-N$ removal rate was accomplished up to $0.71 kg\;NO_3{^-}-N/m^3-day$ in $NO_3{^-}-N$ loading of $0.89 kg\;NO_3{^-}-N/m^3-day$. The maximum $NO_3{^-}-N$ removal efficiency was 95% in $NO_3{^-}-N$ loading of $0.22 kg\;NO_3{^-}-N/m^3-day$. T-N removal rate was 90% and concentration of T-N in effluent was 3.7 mg/L in T-N loading rate of $0.039 kg\;NO_3{^-}-N/m^3-day$. In this study, TMP in reactor with and without non-woven fabric filter were observed to define fouling of hollow-fiber membrane module. Reaching time to standard washing pressure(22 cm Hg) of two reactors were 29 days with non-woven fabric But the reactor without non-woven fabric reached standard washing pressure only after 4 days. Accordingly, non-woven fabric was demonstrated the superiority as a filtration ability. With high nitrogen removal rate and decreasing of fouling of membrane, MBR packed with granular sulfur covered with non-woven fabric filter submerging in activated sludge aeration tank can be used as an advanced treatment process.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.576-580
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• 1997

Lipoxygenase activity in Chinese cabbage was measured at various concentrations of brines. Lipoxygenase activity on linoleic acid substrate was determined by changing the rate of dissolved oxygen consumption. The inactivation of lipoxygenase by salting was increased when concentration of sodium chloride and soaking time were increased. About 60% of enzyme activity was reduced after submerging in 13% brine solution for 5 hr. The addition of calcium chloride (0.7%) reduced about $10{\sim}15%$ of lipoxygenase activity rather than without. Residual activity of lipoxygenase in Chinese cabbage submerged in 13% brine was 20% and about 60% of lipoxygenase was also inhibited by addition of garlic extract.