• Korean Journal of Environment and Ecology
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• v.31 no.6
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• pp.529-536
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• 2017

The study is intended to investigate the proliferation of whitening, the impact of climate change (sea temperature rise) on the proliferation of whitening, and the reproduction and growth of crustose coralline algae, which causes the whitening, in the coast of Jeju Island. The size of the whitening-affected area in the coast of Jeju was 2,931ha in 1998 and increased to 4,541ha in 2003. The whitening occurred mainly in the southern coast of Jeju in 1998 but spread across the whole coast of Jeju by 2003, except in the coast of Jocheon-eup (eup refers to an administrative district in Korea) and Gujwa-eup. The average sea water temperature in February from 1992 to 2004 was $15.1^{\circ}C$ in the whitening affected area and $13.9^{\circ}C$ in the marine forest area, showing a clear difference, but there was no difference in the average temperature in August. The long-term (37-year period) average of the sea temperature was $15.3^{\circ}C$ in the whitening affected area and $14.1^{\circ}C$ in the marine forest area, showing $1.2^{\circ}C$ higher in the whitening area. The annual rate of sea temperature rise was $0.038^{\circ}C$ in the whitening area and $0.024^{\circ}C$ in the marine forest area, indicating the higher long-term variation of sea temperature in the water affected by whitening. The results indicate that the continuous increase in winter water temperature due to climate change is expanding proliferation of whitening in the Jeju island.

• Korean Journal of Human Ecology
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• v.13 no.2
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• pp.271-282
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• 2004

The purposes of this study were to research the behavior of consumption and needs about the female university students to provide useful information which would help finding the marketing source of cosmeceuticals. The sample was consisted of 464 female university students who had experiences of using the cosmeceuticals. Data were analyzed by factor analysis, frequency, x2-test, t-test, ANOVA(LSD) using SPSSWIN. The results were as follows: When the female university students purchased the cosmeceuticals, they considered the effectiveness and the price, so were satisfied with good effect and low price. The most important marketing methods in cosmeceuticals for female university students were through the internet and mail order shopping. Whereas, demerit factors of internet shopping were founded to be the complexity of exchange or refund and the little chance of free samples for trial. The good marketing strategies might be sending trial samples, future payment system after trial period, and/or supporting the event held in the university. Besides, it might be a consideration to have an event for the improvement by public trial. Anti-aging cosmeceutical was the most preferred item for female students, sun protection and whitening cosmetics next in order. Therefore, a target customer for cosmeceuticals might be lowered in age. The purchasing cost system and therapeutic effect of cosmeceuticals had to be developed for 20's. It was necessary to be safe and effective. The factors affecting the level of satisfaction for cosmeceuticals could be categorized into 4; market environment, simplicity of purchase, product merit and additional service. The needs for cosmeceuticals showed significant differences according to grade and kinds of product.

• Journal of Conservation Science
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• v.25 no.4
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• pp.373-381
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• 2009

To preserve steel cultural properties on display outdoors, the surface of these relics is processed with a covering treatment, which is a typical anti-corrosion method. Since the registered cultural heritage of Korea No. 78 Locomotive at Jangdan Station of Gyeongui Line will be treated by preservation process and displayed in the open outdoor area, effective surface covering agents were selected through testing to prevent the corrosion of the locomotive. The mixed wax are based on two types of microcrystalline wax which is one of regular surface covering agents for locomotives and bee‘s wax. For the weather resistance test, 3 types of wax were applied to each specimen of the locomotive and the specimens were tested in the Xenon-Arc Accelerated Weathering Tester for 1000 hours in accordance with the ISO 4892-1981 criteria and the test results were compared. As a result, on the surface of the specimen coated with the bee's wax, a whitening event appears after 400 hours which causes aging, and the specimens coated by the microcrystalline wax showed signs of a whitening event after 800 hours. The moisture contact angle with the microcrystalline wax coating was also less than with the bee's wax. Therefore, it was found that the high temperature microcrystalline wax is the most effective coating agent in terms of weather resistance and moisture blocking capability and the high temperature microcrystalline wax was adopted for coating the surface of the locomotive.

• The Journal of Fisheries Business Administration
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• v.42 no.1
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• pp.37-55
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• 2011

This study is to examine the economic effects of seaweed forest creation project in the case of Jeju Woodo Seokwang－ri. Seaweed forest creation project will raise up the quality and quantity of coastal fisheries resource and improve the structure of coastal ecosystem as a project the recovery of coastal fisheries resource against barren ground like whitening event. The economic effect by seaweed forest creation project can be found not only in the income increase of fishermen but also in reduction of carbon dioxide. The results of this study are summarized as follows: First, the income increase effect of fishermen has economic value of 26,945 thousand won under a 30-year cash flow based on a 8.5% discount rate. This suggests that the seaweed forest creation project increases income of fishermen. Second, the reduction effect of carbon dioxide has economic value of 1,083 thousand won per year. This indicates that the seaweed forest creation project reduces carbon dioxide. In conclusion, the results of this study suggest the seaweed forest creation project has economic value in the case of Jeju Woodo Seokwang-ri.

• Geophysics and Geophysical Exploration
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• v.19 no.1
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• pp.11-19
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• 2016

Two representative residual static methods of traveltime decomposition and stack-power maximization are discussed in terms of application to land seismic data. For the model data with synthetic shot/receiver statics (time shift) applied and random noises added, continuities of reflection event are much improved by stack-power maximization method, resulting the derived time-shifts approximately equal to the synthetic statics. Optimal parameters (maximum allowable shift, correlation window, iteration number) for residual statics are effectively chosen with diagnostic displays of CSP (common shot point) stack and CRP (common receiver point) stack as well as CMP gather. In addition to removal of long-wavelength time shift by refraction statics, prior to residual statics, processing steps of f-k filter, predictive deconvolution and time variant spectral whitening are employed to attenuate noises and thereby to minimize the error during the correlation process. The reflectors including horizontal layer of reservoir are more clearly shown in the variable-density section through repicking the velocities after residual statics and inverse NMO correction.

• Journal of Conservation Science
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• v.31 no.2
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• pp.87-94
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• 2015

Plastic artwork can be appeared crack, change of color and whitening event by various environment conditions. A large scale plastic artwork often exhibits in outside it will be directly degraded by physical and chemical degradation factor such as strong sunlight, high humidity and rainfall. We should know degradation characteristic of plastics to prevent these damages. In this study, we studied degradation characteristic of plastics (5 types of wide use plastics; polypropylene, polystyrene, polyethylene, polyvinyl chloride, polyurethane) depending on various artificial degradation conditions such as high temperature, ultraviolet and these complex conditions (high temperature and ultraviolet). As a result, polypropylene, polystyrene and polyethylene show the most visible change especially polypropylene, polystyrene. Polypropylene didn't show a great change degree of tensile strength and contact angle, on the other hand polystyrene did. Polypropylene and polystyrene weakened by photo degradation, polyvinyl chloride and polyurethane had relatively good light stability. Also the high temperature and complex conditions were most degradation characteristic. High temperature worked for degradation catalyst because its energy can not enough worked for cut off binding energy of plastics while ultraviolet condition effected as directly degradation condition. Though following results, we expect it can be applied to investigation of degradation factor depending on plastic artwork materials and basic result of plastic artworks conservation.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.6
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• pp.577-583
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• 2011

In 2007, pet food contaminated with melamine caused hundreds of dogs and cats to develop renal failure all over the world. In 2008, over 294,000 infants consumed infant formula and developed kidney stones in China. Further investigation revealed that fish feed also contained melamine; this raised concerns about melamine residues in edible fish tissues, which could have caused the urinary tract stone epidemic. In Korea, catfish fed with assorted feed that included cuttlefish organs that contained melamine developed whitening syndrome and fell dead in some populations in 2008. This event raised suspicions about the toxicity of melamine and all feeds containing melamine were immediately recalled. In this study, we investigated the rates of melamine accumulation and depletion in muscle and viscera of catfish to propose proper withdrawal periods. One group of catfish was fed a commercially available diet that contained 30, 100 and 300 mg melamine per kg diet for 14 days. To investigate residual melamine contents in muscle and viscera, other experimental groups were fed a melamine free diet after being fed melamine for 7 days. The residual amount of melamine was analyzed by LC-MS/MS. The melamine concentration in muscle was estimated to be 3.7 mg/kg after 6 days of feeding with a diet containing 300 mg melamine/kg. After 2 days of culture with a melamine free diet, the residual melamine was depleted and the concentration had decreased from 1.15 mg/kg to 0.19 mg/kg in the muscle of catfish fed a diet containing 300 mg melamine/kg for 7 days. The residual amount of melamine was reduced to 0.03 mg/kg in muscle after 7 days of culture with a melamine free diet and was undetectable after a prolonged culture period of 14 days. Catfish tend to excrete melamine rapidly after oral administration and changes in body color were not observed during the short dosing period.

• Journal of the Mineralogical Society of Korea
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• v.30 no.1
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• pp.31-43
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• 2017

This study investigated mineralogy, spectral characteristics and heavy metal contamination including Cd, Ni, Al, Fe, Mn and S for white precipitation in Miin falls based on XRF, XRD, and spectrometer. As a result, Al concentration was abnormally high at all samples, and most of the samples showed high contamination level in Cd and Ni. XRD results detected quartz, kaolinite, rhomboclase, aluminocoquimbite, and gibbsite which infers that heavy metal elements are distributed by adsorption with clay minerals. Spectral characteristics of white precipitation can be described by increasing pattern of reflectance in visible spectrum and decreasing pattern of reflectance in longer wave length including near infrared and shortwave infrared spectrum. The absorption features reveals that spectral characteristics of white precipitation is mainly controlled by kaolinite, rhomboclase, aluminocoquimbite, and gibbsite. The relationship between heavy metal concentration and absorption depth showed high positive correlation for Al concentration and absorption feature at 2202 nm of Al-OH absorption. This spectral characteristics indicates that absorption depth could be effectively used for estimation of heavy metal concentration.