• Journal of Wetlands Research
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• v.7 no.4
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• pp.67-80
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• 2005

Vegetation structure of the vascular plants was investigated from April 2003 to August 2003 in Hwangjeong wetland around Geumho River, Yeongcheon-si, Gyeongsangbuk-do, Korea. Actual vegetation of Hwangjeong wetland largely can be classified by the floristic composition and the physiognomy into 12 communities; Ambrosia artemisiifolia var. elatior, Humulus japonicus, Miscanthus sacchariflorus, Phragmites japonica, Zizania latifolia-Miscanthus sacchariflorus, Zizania latifolia-Nymphoides peltata, Miscanthus sacchariflorus-Phragmites japonica, Phragmites communis-Phragmites japonica, Phragmites japonica-Salix gracilistyla, Salix koreensis-Salix glandulosa, Salix nipponica-Salix koreensis, and Phragmites japonica-Zizania latifolia. Among them, the distribution area of the Phragmites japonica community was the largest as 49.46 ha(11.03%). The dominant vegetation type was Phragmites japonica community and Ambrosia artemisiifolia var. elatior community based on the phytosociological method, and Phragmites japonica community was classified into two subcommunities; Nymphoides peltata subcommunity and Salix glandulosa subcommunity. Differential species of Phragmites japonica community were Phragmites japonica, Miscanthus sacchariflorus, Persicaria thunbergii, Oenanthe javanica, Leersia oryzoides var. japonica, and Rorippa indica; differential species of Ambrosia artemisiifolia var. elatior community were Ambrosia artemisiifolia var. elatior, Setaria glauca, Commelina communis, Cyperus orthostachyus, Digitaria sanguinalis, Xanthium strumarium, Erigeron annuus, Erigeron canadensis, Kummerowia striata, Trifolium repens, and Medicago sativa; differential species of Nymphoides peltata subcommunity were Nymphoides peltata, Zizania latifolia, Scirpus tabernaemontani, and Eleocharis mamillata var. cyclocarpa; differential species of Salix glandulosa subcommunity were Salix glandulosa, Salix koreensis, and Salix gracilistyla. It was expected that Hwangjeong wetland is worthy of conservation contributed purifying water pollution, giving habitats of many lifes, and providing beautiful scenes of Geumho River.

• Journal of Wetlands Research
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• v.6 no.1
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• pp.133-147
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• 2004

Environmental quality(water and sediment) was analyzed in the tidal flat of Saemangum of Jeonbuk Province, the west coast of Korea, using the 101 sediment samples and 69 water samples collected in September 4~13, 2001. Major water quality parameters with the means of 69 surface water samples are as follows; $25.51{\pm}0.68^{\circ}C$ for water temperature, $29.88{\pm}5.01$ for salinity, $1.40{\pm}0.78mg/L$ for COD, $0.352{\pm}0.417mg/L$ for DIN, and $0.027{\pm}0.023mg/L$ for phosphate, respectively. Higher values were found at the subestuary of Dongjin and Mangyung River, and lower values at the Saemangum embayment and Gomso Bay. There was a significant negative correlation between salinity and the other water quality parameters(p<0.0001) such as COD, nutrients, SS and N/P. This correlation suggested that the major pollution sources be from terrestrial inputs through tributaries in this area. Principal component analysis clearly revealed a spatial variation of water quality; stations with higher values of nutrients and COD located subestuary of tributaries. 14 sediment quality parameters including 8 trace metals were measured using the 101 surface sediment samples. Average values for the parameters are as follows; Al $2.28{\pm}0.92%$, Cd $0.61{\pm}0.27ppm$, Cu $8.95{\pm}4.06ppm$, Fe $1.19{\pm}0.37%$, Mn $182.31{\pm}77.45ppm$, Ni $10.83{\pm}4.97ppm$, Pb $15.20{\pm}4.35ppm$, Zn $41.34{\pm}34.62ppm$, COD $2.68{\pm}1.85mg/g\;dry$, AVS $0.04{\pm}0.08mg/g\;dry$, IL $1.29{\pm}1.08%$, water content $24.11{\pm}4.49%$, TN $0.02{\pm}0.02%$, TC $0.22{\pm}0.30%$. Spatial variations of sediment quality were not clear as water quality. Some higher values were found at the subestuary of Gum River and lower values at the other area. There was a significant positive correlation between the heavy metal concentrations and organic materials within the sediment(p<0.05). Enrichment factors showed the ranges of 1~2 for most of the metals in the sediment except zinc(1~6), indicating no serious exogenous input of heavy metals in the study area. Also, the heavy metal concentrations in the sediment were within the ranges found at the natural marine environments.

• Korean Chemical Engineering Research
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• v.47 no.3
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• pp.349-354
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• 2009

In this study, a bubbling fluidized-bed reactor was used to study $CO_2$ capture from flue gas using a potassium-based dry sorbent. A dry sorbent, manufactured by the Korea Electric Power Research Institute, consists of 35% of $K_2CO_3$ for $CO_2$ absorption and 65% of supporters for mechanical strength. $H_2O$, a reactant of the carbonation reaction, was supplied in the reactor as a form of saturated water vapor at a given temperature. The experiment of the regeneration reaction was performed by raising up to a given temperature using $N_2$ as a fluidization gas. It was indicated that sorption capacity and regenerability of dry sorbents showed high-efficiency at $1.97\;mol\;H_2O/mol\;CO_2$ and $400^{\circ}C$, respectively. The regenerated sorbent samples were analyzed by TGA to confirm the extent of the reaction. When the regeneration temperature was $150^{\circ}C$, the regenerability of dry sorbents was about 60%, which was capable of applying those sorbents to a two-interconnected fluidized-bed reactor system with continuous solid circulation. The results obtained in this study can be used as basic data for designing and operating a large scale $CO_2$ capture process with two fluidized-bed reactors.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.31 no.2
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• pp.118-127
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• 2013

In this study, Seongbuk-dong historical & cultural resources of the surrounding landscape were analyzed by the visual characteristics of the landscape adjective analysis. Research was investigate to the relationship between visual characteristics and preferences and Research in the following way. Selected historical and cultural resources in the surrounding area are located in Seongbuk-dong 30 slices the survey was conducted. Landscape preference factors to identify the scale of 16 adjectives and then factor analysis was conducted. Lastly, Analysis of variance and regression analysis were conducted in order to determine the impact of the last image factors on visual preferences. Firstly, The results can be summarized as follows. Officer for 30 pictures appear in Seongbuk-dong in the historical and cultural resources, and distributed around the target preference for the 16 adjectives analysis yielded an average result of overall preference were analyzed and that is a 3.72 average. In these photos, VP8, VP9, VP10, VP12, VP15; 4.5 points more than one order higher. The reason is limit of altitude by the Seoul landscape plan for the historical and cultural resources around. It also judged important reason that history and Culture are in harmony with the surrounding cultural property in the conservation area. Secondly, Important factors are factor 1(aesthetic factors), factor 2(cultural factors), factor 3(physical factors) and three factors could be identified. Results of the analysis of variance and regression analysis about factors for visual preference and image shows value of psychological factor is most significant to explain for nearby history &cultural resources of Seongbuk-dong of scenery around. As a result, the state can not view historical and cultural resources for analysis will be located in a residential area near the historical and cultural resources for aesthetic factors. Third, the negative side of the argument is a residential area which is not arranged surrounding landscape maintenance of historical and cultural resources has emerged. Historical and cultural resources in harmony with the phenomena of the physical, cultural, and aesthetic characteristics of the three areas is a positive factor in the high incidence. Factors from that are expressed in this study by analyzing multi-dimensional analysis to derive a factor to be considered important in the management of historical and cultural resources, landscape around is required.

• KIPS Transactions on Software and Data Engineering
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• v.2 no.9
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• pp.595-602
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• 2013

WiFi fingerprinting is well known as an effective localization technique used for indoor environments. However, this technique requires a large amount of pre-built fingerprint maps over the entire space. Moreover, due to environmental changes, these maps have to be newly built or updated periodically by experts. As a way to avoid this problem, crowd-sourced fingerprint mapping attracts many interests from researchers. This approach supports many volunteer users to share their WiFi fingerprints collected at a specific environment. Therefore, crowd-sourced fingerprinting can automatically update fingerprint maps up-to-date. In most previous systems, however, individual users were asked to enter their positions manually to build their local fingerprint maps. Moreover, the systems do not have any principled mechanism to keep fingerprint maps clean by detecting and filtering out erroneous fingerprints collected from multiple users. In this paper, we present the design of a crowd-sourced fingerprint mapping and localization(CMAL) system. The proposed system can not only automatically build and/or update WiFi fingerprint maps from fingerprint collections provided by multiple smartphone users, but also simultaneously track their positions using the up-to-date maps. The CMAL system consists of multiple clients to work on individual smartphones to collect fingerprints and a central server to maintain a database of fingerprint maps. Each client contains a particle filter-based WiFi SLAM engine, tracking the smartphone user's position and building each local fingerprint map. The server of our system adopts a Gaussian interpolation-based error filtering algorithm to maintain the integrity of fingerprint maps. Through various experiments, we show the high performance of our system.

• Journal of Korean Ophthalmic Optics Society
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• v.18 no.3
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• pp.321-327
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• 2013

Purpose: To investigate a correlation between vertical fixation disparity and stereopsis by analyzing distribution of types of vertical fixation disparity. Methods: In this study, RANDOT(R) stereotest partly using random dot was used in stereopsis tests. The vertical fixation disparity in close proximity categorized fixation disparity slope into six types on the basis of the result of measurement in when two thin lines, one for one eye looks, become overlapped as a line by adding into prism with Wesson fixation disparity card while maintaining a distance of 25 cm from patients. Results: In the types of near vertical fixation disparity curve, targeting 43 people, the first type 55.82% was the most distributed, the second type is the least 23.25%, the third type of 4.65%, the fourth type of 4.65%, the fifth type of 6.98%, the sixths types of 4.65% were distributed. The result of a correlation analysis, which shows the degree of linear correlation between two variables, represented that stereopsis is not correlated with Y-intercept (r = -0.07) which show vertical fixation disparity, associated phoria (r = -0.03) and dissociated phoria (r = -0.00), but it was not statistically significant (p>0.05). Fixation disparity slope of vertical fixation disparity (r = 0.36) was shown to have a positive correlation with stereopsis. It has a low positive correlation and a meaningful statistics (p<0.05). The Y-intercept which indicates vertical fixation disparity was also not associated with stereopsis (r = -0.07) and dissociated phoria (r = -0.03), and this was not statistically significant (p>0.05), while it had a high correlation as well as a statistically significant with associated phoria (r = 0.89). There was a negative correlation between Y-intercept and fixation disparity slope of vertical fixation disparity (r = -0.33). It showed a low relationship but statistically valuable (p>0.05). As a result of regression analysis, the stereopsis was changed as 7.631" if vertical fixation disparity changes 1' and the vertical fixation disparity changed as 0.017' if stereopsis changes 1', and the change was statistically significant (p<0.05). Conclusions: The study shows that there is a low correlation between stereopsis and vertical fixation disparity, and it is difficult to determine stereopsis only using vertical fixation disparity. Therefore, it suggests other factors above vertical fixation disparity have greater influence on stereopsis.

• Journal of Korean Society of Forest Science
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• v.55 no.1
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• pp.59-67
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• 1982

The objectives of this report is to evaluate the contribution of forest investments by the forest owners for the developments of private forests in the villages where the forest production, especially, chestnut production is active. The results obtained are as follows : 1) Newly purchased forest lands of 526 hectares, 71 percent, in 741 hectares by 96 farmers were replanted with chestnut trees for chestnut production. 2) As the chestnut production is considered to be the unique source of the early capital return in management of forests, selling and buying of forest lands in the area surveyed are enhanced to reforest the forest land with chestnut seedlings. 3) Most of new farmers being engaged in plantation and production of chestnuts in the forests are employees of private industries and government agencies, and merchants in neighboring towns. 4) All materials and expenses for formation of chestnut orchards are generally supplied by forest land owners. 5) Active buying and selling of newly established chestnut bushes are surely served as the estate in the area, thus, the trading of the bushes of young chestnut seedling also enhances the forest as the estate. 6) The management of forest established with chestnut orchards is a special form for forest investment, it makes possible to encourage imputing of capital to the new form of forests, chestnut orchards, and it could be a good possible model for private forest development as compared with that of government funding.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.720-726
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• 2007

This study was performed to investigate effects of raw sea tangle products on idiopathic constipation. A total of thirty-eight women participated voluntarily in this study. They were placed into one of four groups by their total colonic transit time (TCTT) to make the four groups have the same TCTT. In the first trial, the subjects in Control group were fed 3 times of 150 mL of mineral water per day for 2 weeks, those in +Control group were fed a kind of stool softener as well as the same mineral water for 3 times, those in STT group were fed 3 times of 150 mL of sea tangle tea and those in STB group were fed 3 times of 150 mL of sea tangle beverage. After 6 weeks, a second trial was performed for another 2 weeks. Although the TCTT of the group exposed to of KolomarkTM was not significantly reduced, the subjects in STT group answered that their evacuation activities were significantly improved; evacuation frequency was increased, stool hardness was reduced, evacuation straining was lessened, stool amount was increased, incomplete sense of evacuation was lessened, and major evacuation time was improved like those in +Control group. The results imply that it is worthy to develop some products of raw sea tangle such as STT, which are effective in treating or preventing constipation.

• Journal of Conservation Science
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• v.27 no.3
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• pp.333-344
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• 2011

Cleaning of foreign matter and corrosion products on surface among conservation treatment of iron artifacts is an important part for looking up a original form. The sand blaster is the most popular equipment when it removes the foreign matter and corrosion products on iron artifacts surface. Current foreign matter and corrosion products equipment, which mostly uses, is sand blaster. Glass dust which sprayed from sand blaster is harmful and causing environmental pollution. In order to solve these problems, we investigated the $CO_2$ snow cleaning that use a eco-friendly equipment to apply for cleaning foreign matter and corrosion products on surface of iron artifacts. It examined by using sand blaster and $CO_2$ snow cleaning to aged steel coupon and iron artifacts. In case of aged steel coupon, the result showed that the sand blaster and $CO_2$ snow cleaning methods were similar to the degrees of cleaning foreign matter and corrosion products, through surface roughness, color measurement and SEM. $CO_2$ snow cleaning applied to aged steel coupons weren't worn out the surface in comparison with sand blaster by SEM. When applied to the iron artifacts, power nozzle of the $CO_2$ snow cleaning was an excellent cleaning effect that surface wern't worn out in comparison with sand blaster. And, it showed that internal structure change of metal was no found before and after cleaning by X-ray radiography. Consequently, we confirmed that cleaning of the sand blaster and power nozzle of $CO_2$ snow cleaning were similar to the effect. But, it's very careful to use this method because of high outlet pressure of power nozzle for applying to the iron artifacts. As a result of experiments, it could be found that the cleaning methods should be selected depending on internal state of the artifacts.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.9
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• pp.636-642
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• 2013

In order to overcome drawbacks (i.e., filtration and recovery) of conventional powder type photocatalysts, nano-ZnO/Laponite/PVA (ZLP) photocatalyzed adsorption balls were developed by using in situ mixing of nanoscale ZnO as a photocatalyst, and Laponite as both adsorbent and supporting media in deionized water, followed by the poly vinyl alcohol polymerization with boric acid. The optimum mixing ratio of nano-ZnO:Laponite:PVA:deionized water was found to be 3:1:1:16 (by weight), and the mesh and film produced by PVA polymerization with boric acid might inhibit both swelling of Laponite and detachment of nanoscale ZnO from ZLP balls. Drying ZLP balls with microwave (600 watt) was found to produce ZLP balls with stable structure in water, and various sizes (55~500 ${\mu}m$) of pore were found to be distributed based on SEM and TEM results. In the initial period of reaction (i. e., 40 min), adsorption through ionic interaction between methylene blue and Laponite was the main removal mechanism. After the saturation of methylene blue to available adsorption sites for Laponite, the photocatalytic degradation of methylene blue occurred. The effective removal of methylene blue was attributed to adsorption and photocatalytic degradation. Based on the results from this study, synthesized ZLP photocatalyzed adsorption balls were expected to remove recalcitrant organic compounds effectively through both adsorption and photocatalytic degradation, and the risks of environmental receptors caused by detachment of nanoscale photocatalysts can be reduced.