• Textile Coloration and Finishing
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• v.14 no.3
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• pp.44-52
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• 2002

Recently there has been a growing interest in the use of natural dyes in textile applications. Natural dyes can exhibit better biodegradability and generally have a higher compatibility with the environment. In this study, the colorants of Catalpa ovata bark were extracted with water and analyzed by spectrophotometry for their main colorant species. Cotton, silk and wool fabrics have been dyed with aqueous extract of Catalpa ovata bark and their dyeabilities on the fibers were studied. Additionally the fastness to washing, drycleaning and light, and the effects on bacteriostatic rate and UV-B protection rate were also investigated. The major colorant of the extract of Catalpa ovata bark was shown to be 6-O-trans-caffeoyl-$\beta$-D-glucopyranoside. Cotton, silk and wool fabrics dyed with the extract of Catnip ovata bark were colored in yellowish red tint. The optimum dyeing condition of the colorants extracted from Catalp ovata bark was three repeated dyeing at $95^\circ{C}$ for 1 hr using post mordanting. For dyed silk and wool fabric, the fastness to washing were improved by mordanting, and the fastness to drycleaning were very outstanding. In case of wool fabric dyed with the extract of Catalpa ovata bark, the bacteriostatic rate was increased drastically by 98.0%, and UV-B protection rate was increased by 97.3%.

• Journal of the Korean institute of surface engineering
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• v.49 no.4
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• pp.349-356
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• 2016

In this study, electrochemical damage behaviors with flow rate were investigated for anodized 5083 aluminum alloy in seawater. As the results of anodic polarization experiments and potentiostatic experiments at +1.0 V (vs. SSCE), the non-flow condition presented largely damaged surface resulting from a tendency of local pitting damage. Under various flow rate conditions, however, less surface damages under the application of anodic potential was obtained which is attributed to no accumulation of $H^+$ and $Cl^-$ ions on the surface. On the other hand, the results of the potentiostatic experiments at -1.0 V (vs. SSCE) with flow rate showed that anodized 5083 aluminum alloys could achieve the effective cathodic protection by low cathodic protection current density less than $2.61{\times}10^{-7}A/cm^2$ even under high flow rate of 1 m/s.

• Journal of Environmental Science International
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• v.13 no.3
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• pp.263-277
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• 2004

The purpose of this study is to analyze the characteristics of riverbed variation due to the sediment protection weir located on the estuary of the main stream of Taehwa river using I-D finite difference model, HEC-6 model, and the followings are the results of estimating sediment transport rate, amount of scour or deposition, and accumulated amount of deposit according to before and after of the sediment protection weir removal with various flow rates in the channel. Ackers-White transport function produced the greatest sediment transport rate while Meyer-Peter showed the smallest sediment transport rate at the most down stream area of the watershed through the sediment transport rate analyses for various flow rates according to the existence or nonexistence of the sediment protection weir. Toffaleti's and Colby transport function were closest to the average value, and the difference among the results of the sediment transport functions showed up to 8～9 times. Duboy's transport function produced the greatest riverbed variation while Toffaleti's showed the smallest variation through the riverbed variation analyses according to the existence or nonexistence of the sediment protection weir. Yang's was closest to the average value, and the difference among the results of the riverbed variation analyses ranged from 1.4 times to 11 times. It is thought that a sediment transport function must be selected very carefully with respect to the criteria of sediment yield estimation because the analysis results of the sediment transport rate and riverbed variation according to flow rates showed significant differences among the sediment transport functions, and the differences of sediment transport rate and riverbed variation according to the various sediment transport functions decreased as the flow rate increased.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2011.07a
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• pp.294-295
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• 2011

The fundamental problem of selective protection scheme for encoded bitstreams is to find an efficient algorithm to select the set of frames required to be encrypted that can maximize protection effect with the minimum amount of protected data is required. In this paper, we propose an optimal selective protection scheme for SVC bitstreams by protecting the best combination of frames for selective protection in the sense that the amount of data required for protection is minimized and the resulting visual quality degradation is maximized. The selection of the frames to be encrypted is done by first expressing R-Q (protection rate - visual quality) relationship with Lagragian cost model. The experimental results show that, compared to protecting SVC bitstreams layer by layer, the proposed scheme gives superior performance in terms of protection effectiveness due to its better selection of frames for protection given protection bit budgets.

• Proceedings of the Korea Technology Innovation Society Conference
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• 2006.11b
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• pp.371-396
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• 2006

To see the implication of trade policy in endogeneous growth model, we introduce trade protection that takes the form of an import tariff and represents one plus the rate of protection provided to industry sector. We showed that considering goodness of fit of regression model, we can see that the empirical evidence is strongly in favor of the character of trade policies as the instrument spurring economic growth. As for import tariff, we see that 1% increase in the rate of tariff that protect domestic market causes the rate of growth to increase by 0.87%. An import tariff to final product significantly spurs product development and faster growth come as a result. But, we should note that the effects of trade policy are muted by the induced changes in the output of intermediates in an economy that is relatively unproductive in the research lab.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.28 no.2
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• pp.216-227
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• 1992

The corrosion rate, behavior of corrosion fatigue and characteristic of cathodic protection for SB41 were investigated by corrosion and corrosion control tests in seawater at laboratory and coast. The main result obtained are as the following; 1) The corrosion rate of base metal (BM) is about 28-37 mg/dm super(2) day in seawater of coast. 2) The correlation between the stress intensity factor range $\Delta$K and crack propagation rate da/dN for weldment follows paris' rule in seawater : da/dN=C($\Delta$K) super(m) where m is the slope of the correlation, and is 2.02 for BM and 1.75 for heat affected zone (HAZ) respectively. 3) The corrosion sensitivity of HAZ is more sensitive than that of BM under the low region of $\Delta$K. 4) With increase of bared surace area of cathode, cathodic protection potential is increased sharply.

• Journal of the Korean Home Economics Association
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• v.41 no.7
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• pp.13-24
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• 2003

Recently there has been interested in the use of natural dyes in textile applications. Generally natural dyes can exhibit better biodegradability and have a higher compatibility with the environment. In this study, cotton, wool and silk fabrics were dyed with alkali extract of Arecae semen using various mordants, and their dyeabilities were discussed. Additionally the fastness to washing, perspiration, light, rubbing, and drycleaning and UV-B protection rate were also investigated. Cotton, silk and wool fabrics dyed with alkali extract of Arecae semen were colored in reddish yellow tint. The optimum dyeing condition of the colorants extracted from the Alecae semen was three repeated dyeing at $95^{\circ}C$ for 1.5 hrs. The dyed fabrics by using mordanting methods improved the fastness to washing, perspiration and drycleaning, but the fastness to light and rubbing were not increased. The UV-B protection rate of the wool fabrics were increased by dyeing with extract of Arecae semen.

• The Journal of Fisheries Business Administration
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• v.53 no.4
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• pp.51-67
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• 2022

The Korean tariff rate for fishery products is a single tax rate of 10% for live fish and frozen seafood, and 20% for all others. Since FTAs have been concluded with several countries, the tariffs is not an appropriate means to protect domestic fishery producers. The differential tariff rate according to the scientific name (genus) of the fishery products, which was implemented 30 years ago to protect fishery products produced in the Korean coastal waters has lost its original purpose. It seems that future fishery trade policy should focus on IUU prevention, hygiene and safety of consumers rather than protecting fishery producers through customs tariffs. This paper suggest that a paradigm shift in the fishery producers protection policies such as direct financial support from the state, protection and development of fishery resources, and support for fostering the 6th industry rather than indirect protection through tariffs.

• Journal of the Korean Society of Costume
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• v.56 no.2 s.101
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• pp.147-154
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• 2006

In this study 1, the dyeability and sun protection characteristic of the fabrics dyed with pine needles extract was investigated. In the test of color difference, the surface color of all the dyed fabric of both cotton and silk came to light as greenish yellow. In the test of dyeing colorfastness, the colorfastness to sunlight of dyed cotton fabric was below 2nd grade and the one of dyed silk fabric was below 3rd grade. The colorfastness to laundry for the degree of discoloration showed a difference as to mordants, but the colorfastness to laundry for the degree of contamination was excellent as all the dyed fabrics were 4th-5th grade. The colorfastness to perspiration was excellent as the degree of discoloration was more than 3rd grade and the degree of contamination was more than 4th-5th grade. The colorfastness to rubbing showed the excellent result as all the dyed fabrics were 4th-5th grade. In the test of sun protection factor(SPF), the cotton and silk fabrics dyed with $FeSO_4{\cdot}7H_{2}O$ mordant showed very high sun protection characteristic as the SPF was each 36.1 and 42.5. In the test of sun protection rate for UV-A and UV-B, the cotton and silk fabrics dyed with $FeSO_4{\cdot}7H_{2}O$ mordant showed the very high sun protection rate of more than $90\%$.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.3A
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• pp.296-301
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• 2011

GPS(Global Positioning System) service is more important than other wireless services. The GPS is necessary protected from any other interference signals. Therefore, GPS protection ratio was calculated on the basis of bit error rate(BER) in this paper. Simulation results show that the allowable maximum interference power is -190 dBm/Hz and the ratio of interference to noise(I/N) is -16 dB. The achieved protection ratio is available to be applied as the protection criteria of GPS in considering the implementation margin of 4 dB. As a result, the proposed protection ratio of GPS is expected to give standard for a stable GPS service.