간행물
한국환경과학회지 KCI 등재 Journal of Environmental Science International
- 발행기관 한국환경과학회
- 자료유형 학술지
- 간기 월간
- ISSN 1225-4517 (Print)2287-3503 (Online)
- 수록기간 1992 ~ 2023
- 주제분류 자연과학 > 자연과학일반 자연과학 분류의 다른 간행물
- 십진분류KDC 539DDC 628
권호리스트/논문검색
제18권 제2호 (2009년 2월) 12건
1.
2009.02
서비스 종료(열람 제한)
Development of an artificial neural network model was presented to predict the daily maximum SO2 concentration in the urban-industrial area of Ulsan. The network model was trained during April through September for 2000-2005 using SO2 potential parameters estimated from meteorological and air quality data which are closely related to daily maximum SO2 concentrations. Meteorological data were obtained from regional modeling results, upper air soundings and surface field measurements and were then used to create the SO2 potential parameters such as synoptic conditions, mixing heights, atmospheric stabilities, and surface conditions. In particular, two-stage clustering techniques were used to identify potential index representing major synoptic conditions associated with high SO2 concentration. Two neural network models were developed and tested in different conditions for prediction: the first model was set up to predict daily maximum SO2 at 5 PM on the previous day, and the second was 10 AM for a given forecast day using an additional potential factors related with urban emissions in the early morning. The results showed that the developed models can predict the daily maximum SO2 concentrations with good simulation accuracy of 87% and 96% for the first and second model. respectively, but the limitation of predictive capability was found at a higher or lower concentrations. The increased accuracy for the second model demonstrates that improvements can be made by utilizing more recent air quality data for initialization of the model.
2.
2009.02
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Temperature, salinity, COD, DIN (Dissolved Inorganic Nitrogen), DIP (Dissolved Inorganic Phosphorus), and Chlorophyll a obtained from the southern coastal waters during the period of 2003 to 2005 were analyzed. Variability in temperature was not found between groups in southern coastal waters, but significantly different depending on sampling sites (p<0.05). The average temperature in 2003 estimated at 18.33℃ that was annually increased by 2005 and significantly different based on statistics (p<0.05). Unlikely to temperature, salinity was significantly different depending on sampling sites, as well as monthly variations (p<0.05). Likewise to temperature, the value of salinity was annually increased. COD estimated at the average of >1.7 mg l-1 for three years, indicating optimal water quality. The fluctuations of nutrients were extremely shown in different sampling sites and monthly variations. Chlorophyll a recorded above 2.0 μg l-1 which was associated with high primary phytoplankton, whereas it showed much fluctuations in temporal and spatial, In particular, Tongyong, Jaranman, Jinjuman, and Samcheonpo located in the southeast were the highest fluctuations in water quality than any other regions. The correlation between salinity/COD and nutrients/chlorophyll a was strongly negative or positive, which was possibly associated with much the introduction of run-off water as well as rainfall in summer.
3.
2009.02
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Riparian vegetation gives basic habitats for animal and other biological organisms. It is one of essential landscapes in river ecosystem. This floral study was conducted to give basic information for management of the Geum river ecosystem. We discovered total 69 plant communities out of 40 sites studied and mean 8 plant communities were analysed per study site. Salix koreensis and Salix subfragilis community were dominant of all communities at tree layer and Salix gracilistyla and Rubus parvifolius were dominant communities at shrub layer. Phalaris arundinacea, Phragmites japonica, Miscanthus sacchariflorus and Artemisia princeps var. orientalis appeared most as perennial grasses and Humulus japonicus, Persicaria thunbergii and Persicaria hydropiper appeared most as annual grasses. Robinia pseudoacacia, Amorpha fruticosa and Bidens frondosa were frequently present as exotic species. Grass communities were higher than tree communities because of human disturbance by artificial banks. The number of species was 182 appeared as 53 families 144 species, 34 varieties and 4 forma and mean species number was 25.5 per site. The most abundant site was Yanggang bridge site (14 vegetation association, 49 species) and the least abundant site was Namdaechon, Muju site (3 vegetation association, 12 species). We suggest that continuous riparian vegetation monitoring should be carried out to manage water environment ecologically.
4.
2009.02
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The present study observed temperature in order to identify factors affecting temperature by zoning and to measure the intensity of their impact on temperature. The empirical results of analyzing observed data are as follows. In order to make up for multicollinearity, a problem in multiple regression analysis, and to give more specific explanations, this study conducted factor analysis and obtained desirable data with adequacy and statistical significance. In the correlation matrix, factors decreasing temperature were planted areas, water surfaces and grasslands, and those increasing temperature were bare grounds, paved areas, and building area. According to land cover patterns, commercial areas had the highest temperature lowering effect. Through the rotated component matrix, we found that factors are grouped into those decreasing temperature, those increasing temperature, and those with low significance in increasing or decreasing temperature. In order to solve the problem of multicollinearity in multiple regression analysis, we performed factor analysis between the land use patterns and temperature and confirmed the usability of factor analysis as a new analysis method in urban heat island.
5.
2009.02
서비스 종료(열람 제한)
The changes in the worldwide paradigm of the sustainable development have started to be applied in the entire industry fields, and they come out as the sustainable tourism in the field of tourism. And the ecotourism has emerged as a practical method to meet the needs of the actual practice and the intellectual system for the sustainable tourism. In the type of tourists based on tourist attitude, 82.3% has the environment-friendly tourist attitude as a potential ecological tourist or an ecological tourist. In addition, there are the potentials of increase in ecological tourists as well as the revitalization of ecological tourism. First, the ecological tourists are mostly the well-educated and married professional workers at 40, housewives, and people earning a high income. Next, the potential ecological tourists are mainly the well-educated and married professional workers at 30, workers in the service industry, and middle-class citizens. Lastly, the general tourists are the students at 20 who are single, earn a low income, and has low level of eduction. This study presents useful data to the tourist business in terms of the development, operation and management of sustainable ecological tourism.
6.
2009.02
서비스 종료(열람 제한)
This study was investigated to control the corrosion and scale at the cooling water system in steel works. Laboratory and field tests were performed for the indirect cooling water system of plate mill. Throughout the experiment, various factors such as leakage of pipes, heating rate and capacity, and the reaction between existing and substitute inhibitors were carefully monitored. The results showed that the harmful effect of high temperature could be minimized, and satisfactory corrosion/scale controls were effectively achieved using inhibitor, even at the increased temperature of 80℃. The batch and field tests in the gas scrubbing cooling water system of blast furnace and cooling water system of corex plant indicated that the new inhibitor was more effective for the prevention of corrosion and scale than the existing one.
7.
2009.02
서비스 종료(열람 제한)
The aim of this study is to calculate process emission of GHGs(greenhouse gases) in nonferrous-metal industry, such as Zn, Pb, Cu and Ni. In addition, variation and emission of GHGs generated from these company were defined. And then, GHGs algorithm and calculation formular which were considered as production process in each part of nonferrous-metal industry were developed to develop calculation program of GHGs emission. These algorithm and calculation formular would present fundamental direction about other nonferrous-metal industry in the future.
8.
2009.02
서비스 종료(열람 제한)
A laboratory experiment was conducted to investigate nitrogen removal from plating wastewater by a soil reactor. A combination of soil, waste oyster shell and activated sludge were used as a loading media in a soil reactor. The addition of 20% waste oyster shell and activated sludge to the soil accelerated nitrification (88.6% NH4+-N removal efficiency) and denitrification (84.3% NO3--N removal) in the soil reactor, respectively. In continuous removal, the influent NH4+-N was mostly converted to nitrate nitrogen in the nitrification soil reactor and only a small amount of NH4+-N was found in the effluent. When methanol was added as a carbon source to the denitrification soil reactor, the average removal efficiency of NO3--N significantly increased. The NO3--N removal by methanol addition in the denitrification soil reactor was mainly due to denitrification. The phosphorus was removed by the waste oyster shell media in the nitrification soil reactor. Moreover, the phosphorus removal in the denitrification soil reactor was achieved by synthesis of bacteria and the denitrification under anaerobic conditions. The approximate number of nitrifiers and denitrifiers was 3.3×105 MPN/g soil at a depth of 1～10 cm and 3.3×106 MPN/g soil at a depth of 10～20 cm, respectively, in the soil reactor mixed with a waste oyster shell media and activated sludge.
9.
2009.02
서비스 종료(열람 제한)
Micropollutants, which can be caused by imperfect combustion, are toxic chemical compound that flows into the river system after being contained in road runoff, a non-point source pollutant and accumulates in the body. The micropollutants that have characteristics such as toxicity, persistence, bio-accumulation, long-range transportation behave so similarly to micro particles that they can be removed by means of filtration or absorption. This study has examined the kinds and concentrations of micropollutants contained in deposited road particles. It has revealed that the kinds of micropollutants contained in the clarified supernatant liquid of deposited road particles are heavy metals and polycyclic aromatic hydrocarbons(PAHs) composed of two or three benzene rings, including naphthalene and acenaphthalene. Their concentrations have been shown to be low, with 0.418 mg/L, 0.058 mg/L, 0.104 mg/L, 0.014 mg/L, 0.00075 mg/L for Zn, Pb, Cu, Cr, Cd, respectively and 0.00156 mg/L and 0.00184 mg/L for naphthalene and acenaphthalene.
10.
2009.02
서비스 종료(열람 제한)
In this study, a river basin with a lot of measured data such as water level, flow rate, current speed, and sediment rate from the past to now was selected and geometrical shape of a pier was re-analyzed, in order to study the effects of the flow around the pier area as well as the riverbed alternation characteristics. A finite element mesh of the entire river was prepared, and via parameter revision, the section that the pier has influence on was decided, to analyze the shape of the pier using RMA-2 and SED2D-WES models. With regards to the section that the pier has influence on, analysis was done on the four pier shapes, namely circle, square, rectangle, and octagon. The results showed that the shape with the least influence around the pier around is the octagon, followed by circle, rectangle, and square, showing the different geometrical effects that the shapes have on the pier. Furthermore, it was shown that the distribution of sediment concentration had effect from about (+)110 m of the upstream to about (-)130 m of the downstream, from the pier installation point. Also, it was shown after analyzing drag forces for different sediment particle distributions that the shape with the greatest drag is the octagon, followed by circle, square, and rectangle.
11.
2009.02
서비스 종료(열람 제한)
Characteristics of the transesterification reaction between triglycerides in soy bean oil and methanol were investigated in the presence of acid catalysts. such as sulfuric acid and PTS (p-toluene sulfonic acid). Concentrations of diglyceride and monoglyceride which were intermediates in the reaction mixtures, were far below 10% of triglyceride under any reaction conditions. Thus, conversion of the reaction could be determined from the concentration of triglyceride. Dried PTS had more superior catalytic power than sulfuric acid for transesterification reaction between soy bean oil and methanol. When transesterification reaction of soy bean oil was catalyzed by 1 wt% of PTS at methanol stoichiometric mole ratio of 2 and 65℃, final conversion reached 95% within 48 hours. If FAME (fatty acid methyl ester) was added into reaction mixture of soy bean oil, methanol and PTS catalyst, it converted reaction mixture into homogeneous phase, and substantially increased reaction rate. When reaction mixture was freely boiling which had equal volumetric amount of FAME to soy bean oil, methanol stoichiometric mole ratio of 2 and 1 wt% of PTS, final conversion achieved value of 94% and temperature approached to 110℃ within 2 hours.
12.
2009.02
서비스 종료(열람 제한)
In this study, to stabilize the heavy metal in the contaminated soils, the column leaching test based on rainfall and pH value was performed by using coal mine drainage sludge(CMDS): which was generated during electrical purification of abandoned coal mine wastewater. Four types of testing column were used in this study. That were the CMDS and the heavy metal contaminated soils well mixed in 0 wt%, 1 wt%, 3 wt% and 3 wt% layered column. According to the investigation, when the influent pH was 5.5∼6.2, there were no heavy metal elution at all conditions, and when the influent pH was 3∼3.3, the order of Cu, Zn, Pb, Cr elution concentration was 3 wt% M(mixed)＜3 wt% S(separation)＜1 wt% M＜0 wt% and the average elution concentration was quite low, the value was 0.005 mg/L. Therefore, CMDS can used as new stabilizer of the heavy metal in the contaminated soils.
