• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.204-210
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• 2006

The purple color in flesh of 'Jasim' potato (Solanum tuberosum L.) tubers is due to an accumulation of anthocyanin. The experiment was conducted to determine what is the key factor among cultural environments that affect the accumulation of anthocyanin in 'Jasim' potato tubers, and the effect of nitrogen fertilization levels on that. Through analysis of anthocyanin content of purple-fleshed tubers produced under the different cultural environments of three localities and two planting dates, we determined that lower temperature during 30days before harvesting resulted in higher anthocyanin accumulation of 'Jasim' potato tubers. In the experiment of different level of nitrogen fertilization, 'Jasim' potato tubers produced in highland (Daegualryeong) showed higher content of anthocyanin in the treatment of recommended level than in treatment of lower or higher level as compared with the recommended level. However, significant difference of anthocyanin content among different nitrogen fertilization levels was not observed in lowland (Gangnung). These results suggest that the selection of locality or cropping system and the optimal fertilization management are very important factors for production of higher pigmented tubers in purple-fleshed potato.

• Journal of Bio-Environment Control
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• v.15 no.2
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• pp.177-183
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• 2006

The summer production of sweet pepper in Korea which cultured in the highland area such as Hapchon is essential for a year-round export, but has the problem, fruits lose easily those marketability. This study was carried out to find changes of fruit quality in response to storage on sweet pepper cultivars in summer. Seven cultivars of sweet peppers, 'Jubilee', 'Plenty', 'Goal', 'Romeca', 'Derby', 'Midas' and 'Maximalia' were obtained iron growers in Hapchon which was highland of 600-800m from sea level and stored at $10^{\circ}C$ with box packing. Fruit quality was evaluated every 4days up to 4weeks. The weight loss of 'Jubilee' was the lowest, that of 'Romeca' was the highest. The firmness of 'Goal' was maintained highly for 4weeks and the red cultivars was higher than those of other color cultivars. The lightness of 'Jubilee' was sensitively affected by storage duration. Seeds of 'Plenty' and 'Derby' were plentifully browned after 4weeks storage. The occurrence of fruit rotting was after 16-204ay storage and those of 'Plenty' and 'Maximalia' were the earliest. The marketability of 'Jubilee' and 'Romeca' maintained by 70% for 16 days was the highest, but most cultivars lost those by 20% after 24days storage. It may be suggested that the marketability of sweet pepper producted in summer can be stored at $10^{\circ}C$ for 2weeks to maintain that of 80%.

• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.1 s.28
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• pp.93-102
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• 2007

Particle materials sink in bottom and dissolved inorganic substances release from sediment and many kinds of materials continuously exchange in sediment and water column as well as transfer and transformation in sediment. The study of sediment quality means the state of sediment pollution relation of the water quality, sediment biota, materials fluxes between sediment and water column, transformation of materials in sediment is being important in recent. The state of sediment quality imply that the history of water pollution for long time, because the sediment quality does not change temporally. The sediment quality of bottom water can be used as a good indicator of pollution at present and in future. The major index of sediment qualities are the content of nutrients and hazard materials such as metals, Ignition Loss (IL), Total Sulfur (TS), Oxidation Reduction Potential (ORP), sediment COD, color, odor and the release of nutrients from sediment. However, there are some arguments between researchers about compare to estimation of sediment quality and sampling and analysis of sediment. In this study, I will introduce the method of sediment sampling, analyzing and estimating of the sediment pollution.

• Korean Journal of Environment and Ecology
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• v.21 no.2
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• pp.134-140
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• 2007

The purpose of this study is to investigate the landscape image and visual preference for ridges of the Seongpanak district at Mt. Hallasan. For this, the evaluation of the artificial and natural landscape is compared through the medium of color slides. Data is analyzed through the descriptive statistics and spatial image is analyzed by factor analysis algorithm. Principle component analysis and Varimax Method are applied to extraction and factor rotation respectively. The results of this study can be summarized as follows : General visual imagesthe Seongpanak district at Mt. Hallasan are clean, beautiful and attractive. The degree of visual preference increased commensurately with the lower rate of artificial factors. Landscape Factors covering the spatial image are found to be 'aesthetic value', 'spatial scale', 'natural quality', and 'topography' factor, which account for 57.6% of the total variants. The aesthetic value variable is the most important factor in visual preference and the unnatural factors are found to present negative elements with visual preference.

• 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 Environment and Ecology
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• v.17 no.3
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• pp.285-294
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• 2003

The purpose of this paper is to provide useful knowledge for recreation management in natural park(NP) by evaluating use suitability of recreation resource. We had obtained data through a questionnaire, which surveyed 385 visitors at 6 of the 73 NP in Korea in 2001, based on stratified sampling method. We have analyzed the data using the multiple regression method. We found that 1) in bivariate analysis, the relationships between use suitability and all the recreation resources are fairly high and statistically significant. The higher the degree of recreation resources, the higher the degree of use suitability. 2) in multivariate analysis, topography, social resource(SR), cultural resource(CR), landscape, smell, color and sound(SCS) have been turned out to be statistically significant at one percent level. 3) the direction of relationship between topography, SR, CR, landscape, SCS and use suitability is same. 4) in relative contribution of the use suitability of recreation resource, level of topography has been turned out to have about 1.05, 1.56, 2.16 and 2.70 times more important than that of SCS, SR, landscape, topography, respectively This results will be used for a criterion for recreation resource evaluation and a settlement of management priority and increasing user's satisfaction.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.304-310
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• 2011

To evaluate the effect of curing treatment using a newly developed simplified curing unit (SCU) on the physicochemical quality of stored sweet potatoes was investigated for six months. The SCU consisting of a heater, an air circulation fan, exhaust fans, and a humidifying duct was installed in a cold storage room where the harvested sweet potatoes were stacked. During the six days of curing treatment, air temperature and relative humidity in the storage room were set at $32^{\circ}C$ and 90%, respectively. Physical and chemical properties of sweet potatoes were measured at 1-month intervals from the first day of storage. McKinney index showing the incidence and severity of decay was 0.83% in the curing treatment, while that of untreated control was 5.08% over the same storing period. Firmness, soluble solids content, and dry matter content in the cured sweet potatoes were greater than those of untreated control. Moreover, the changes of skin color in uncured potatoes occurred rapidly than cured one which showed delay of skin discoloration during the long-term storage. Results suggest that the SCU treatment improves the physicochemical quality of stored sweet potatoes and extends their storability. Therefore, the SCU can be effectively used for curing treatment of sweet potatoes with a relatively low cost.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.357-364
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• 2011

Proper light intensity, potting media, fertilization level, and shade tolerance were investigated to develop Orostachys (Korean name, Nungyu bawisol) as a potted ornamental plant. The best plant growth was shown at 52% shading. Although plant growth decreased at 82% shading, ornamental value maintained at that shading rate, which indicate that O. 'Nungyu bawisol' has high shading tolerance. At over 90% shading, some of the plants died and showed decolorization and standing erect in leaves, resulting in a big decrease in ornamental value. Potting medium of decomposed granite (DG) : fertilizer-amended media (FAM) : river sand (RS) (6 : 2 : 2, v/v/v) showed the best growth in potted O. 'Nungyu bawisol'. Fresh weight of shoot part was 16 g in DG : FAM : RS (6 : 2 : 2, v/v/v), which was over 2 folds of those at the other medium. Drenching of Hyponex solution diluted by 1,000~2,000 folds 1 time per week brought the highest results in fresh weight, plant width, and runner number. Particularly, fresh weight of shoot part was 13 g higher than that of control (16 g). Leaf color tended to be darkened as concentration of Hyponex solution increased.

• Journal of Bio-Environment Control
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• v.18 no.2
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• pp.101-106
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• 2009

To study the effect of nonwoven fabric materials on growth and yield of korea melon, Medium denier nonwoven fabrics (MDNF), Polyster nonwoven fabrics (PENF) and 12 ounce nonwoven fabric (control) were used. Mean temperature at night was 13.1$^{\circ}C$ at control, 14.7$^{\circ}C$ at MDNF and 13.3$^{\circ}C$ at PENF from Feb. 6${\sim}$7, 2009. Because of higher temperature, early growth of korea melon of MDNF was better than control at 30 days after transplanting. Days required to harvesting (DRH) of control was 89, those of PENF and MDNF were 88, 78, respectively. First harvesting of MDNF was 11 days earlier than control. Harvested fruit of MDNF had higher weight, soluble solid and marketable fruit ratio than control. Yield ratio of control and PENF was 4:3:3 (early:middle:late harvesting season), but MDNF was 5:3:2. Using of MDNF provided earlier harvesting. Total yield of PENF was similar to control, 1,844kg per lOa, MDNF was increased by 9%.

• Journal of Bio-Environment Control
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• v.27 no.4
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• pp.356-362
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• 2018

Hot pepper is a kind of seasoning vegetables, which is a major item in the Korean vegetable market. Since the use of hot pepper is processed into pepper powder, which is a powder form of dried hot pepper, improvement of quality and productivity of dried hot pepper is important. Therefore, this experiment was conducted to suggest proper drying method by comparing the changes of hot pepper powder ingredients considering production cost according to the drying method. As a drying method, we used sun drying and heat drying which are widely used in practice. We also compared the productivity and quality of dried hot pepper by applying a dehumidifying drying method using a dehumidifier. Drying rate of hot pepper was highest of 85.1% at heat drying. Accordingly moisture content of hot pepper powder was lowest of 13.5% at heat drying. The American Spice Trade Association (ASTA) color value, which influenced the coloring of red pepper, showed higher in heat drying and dehumidified drying treatment than the sun drying treatment. The content of capsaicinoids was higher at sun drying treatment than that of at both heat drying and dehumidified drying treatments. The content of sugar was higher at heat drying and dehumidified drying treatment where drying time was relatively short than that of sun drying treatment. Also, there was no significant difference in sugar content between the two treatments. The production cost of dried hot pepper with dehumidified drying was 9.9% more efficient than heat drying. Through this study, it was found that heat and dehumidified drying method were effective in increasing sugar content and coloring of hot pepper powder. In order to improve the capsaicinoid content of red pepper, it is considered that appropriate drying temperature and drying time should be added in the process of heat drying and dehumidified drying.