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
제9권 제6호 (2000년 12월) 13건
1.
2000.12
서비스 종료(열람 제한)
Chonan and Asan city have been a focal point due to rapid development as the first station for Express Railroad and key cities West Coast Development Region. Gokgyo stream adjacent to the cities plays an important role as a drainage channel for an agriculture and a discharger of urban storm water. Water quality of the stream has been deteriorating caused by pollution sources such as a untreated wastewater discharge and runoff from the watershed.
In this study, we conducted 4 surveys in April, May, July, and September to understand the current state of water quality for the stream and to make it possibe to predict future water-quality variation for future development. The system runs on a personal computer under the windows enviroment and provides extensive graphics using graphic user interface(GUI) for user-friendly assessment. Using the pull-down menus provided by the GUI panel, the user is able to operate the system by pointing and clicking the icon to identify the state of water-quality at locations concerned. Furthermore, we developed an integrated watershed management system. The constructed system could be a useful tool as a decesion maker for pollution source control strategy.
2.
2000.12
서비스 종료(열람 제한)
Sustainable development has been the key concept, both in economic policies and in environmental management. On the basis of an systems ecology perspective, this study suggests the sustainable development of Korea's natural environment and economic activity using the EMERGY evaluation. The total EMERGY use(7,730 E20sej/yr) in Korea is 81 percent from imported sources, fuels and goods and services. The ratio of outside investment to attracting natural resources is already large, like other industrialized countries. Continued availability of purchased inputs at a favorable balance of EMERGY trade, currently about 2.85 to 1 net EMERGY, is the basis for present economic activity and must decrease as the net EMERGY of purchased inputs including fossil fuels goes down. EMERGY yield ratio and environmental loading ratio were 1.23 and 20.30, respectively. The population level is already in excess of carrying capacity. Its carrying capacity for steady state on its renewable sources is only 2.2 million people, compared to 45.9 million in 1997. EMERGY sustainability index is therefore less than one, which is indicative of highly developed consumer oriented economies. Until now the development of a country has been achieved by the economic growth, but it can be sustained in the long run by the use of renewable resource systems, the efficiency of energy usage, and the transformation of the social-economic structure based on an ecological-recycling concept.
3.
2000.12
서비스 종료(열람 제한)
This study aims at the development of the model for a forecasting of water quality in river basins using artificial neural network technique. Water quality by Artificial Neural Network Model forecasted and compared with observed values at the Sangju 1 and Dalsung stations in Nakdong river basin. For it, a multi-layer neural network was constructed to forecast river water quality. The neural network learns continuous-valued input and output data. Input data was selected as BOD, DO, discharge and precipitation. As a result, it showed that method Ⅲ of three methods was suitable more than other methods by statistical test(ME, MSE, Bias and VER). Therefore, it showed that Artificial Neural Network Model was suitable for forecasting river water quality.
4.
2000.12
서비스 종료(열람 제한)
The effect of UV on the mortality rate of toxic dinoflagellate Amphidinium carterae causing a red tide in the coastal area of south Korea was investigated in the batch and continuous-scale reactor equipped with ultraviolet irradiation-apparatus. Degussa P25 titanium oxide, a photocatalyst proved to be effective for the mortality of Amphidinium carterae supplied with photocatalyst and UV radiation were greater than 95% in 2 minutes of UV radiation and the rate were higher than that by UV-radiation without titanium dioxide in the batch and continuous-flow scale reactor. The mortality time of Amphidinium carterae increased with the cell density under UV-illumination in the batch scale reactor. The mortality rate in the density of 5.0×104 cells/mL at the same experimental condition was more than 90% in 4 minutes in the continuous flow scale reactor. The percentage of 99.9±0.1% of Amphidinium carterae in the density of 5.0×104 cells/mL was died in 20 minutes when the phytoplankton was illuminated with UV-radiation without photocatalyst.
5.
2000.12
서비스 종료(열람 제한)
The traffic accidents in large cities such as Pusan metropolitan city have been increased every year due to increasing of vehicles numbers as well as the gravitation of the population. In addition to the carelessness of drivers, many meteorological factors have a great influence on the traffic accidents. Especially, the number of traffic accidents is governed by precipitation, visibility, humidity, cloud amounts and temperature, etc.
In this study, we have analyzed various data of meteorological factors from 1992 to 1997 and determined the standardized values for contributing to each traffic accident. Using the relationship between meteorological factors(visibility, precipitation, relative humidity and cloud amounts) and the total automobile mishaps, an experimental prediction formula for their traffic accident rates was seasonally obtained at Pusan city in 1997.
Therefore, these prediction formulas at each meteorological factor may be used to predict the seasonal traffic accident numbers and contributed to estimate the variation of its value according to the weather condition in Pusan city.
6.
2000.12
서비스 종료(열람 제한)
The purpose of this study is to find out the temporal and spatial characteristics of the diurnal wind variation between coastal and inland areas using the hourly wind data of 58 AWS-stations in the South Korea which are collected during the 10 years from 1980 to 1989. Diurnal variation is investigated by using the Fast Fourier Transform(FFT), and the wind direction is investigated by comparing Cr with Cv represented the constancy of wind.
For the scalar wind speed, the maximum wind speed occurs in the daytime from 14h to 16h. The maximum diurnal amplitude at coastal areas occurs from 12h to 16h, and is about 2 hours faster than that at inland areas. Vector mean wind speed is strong at coastal areas and Chupungnyong, Kumi, Taegu of inland areas. The diurnal variation ellipses make a right angle with coastline show that the land. and sea breezes are prevailing. The constancy of wind is strong at all observations in January. In the relationship between Cr and Cv , Cv is higher than Cr.
7.
2000.12
서비스 종료(열람 제한)
The Temporal Distribution Characteristics of Some Important VOC Species from a Nonurban Site in Naju
In this study, the distribution characteristics of volatile organic compounds (VOCs) were investigated on the seasonal basis across spring, summer, and fall during the year of 1998. According to this analysis, most VOC species investigated exhibited strong temporal trends. Over diurnal scale, there distribution characteristics were affected by seasonal factors strongly. While they showed high day/night ratio pattern during spring, the pattern was reversed during fall. When the seasonal mean values were compared between the two seasons, the spring values were systematically higher than their counterparts in most cases. In addition when our VOC measurement data were compared with those reported from elsewhere, we were able to conclude that the VOC levels in the study area are comparable to the level weakly impacted by the regional emissions of VOCs. Although our data are not sufficient enough to systematically explain the atmospheric distribution and behavior of VOCs, the findings of strong correlations among some of VOC species suggests strong need for investigating their interactions in the earth's atmosphere.
8.
2000.12
서비스 종료(열람 제한)
This research focused on the priority decision for establishment criteria on the effects which environmental sculptures in urban areas. The analysis performed in this study used the AHP(Analytic Hierarchy Process) that is recognized as a useful decision-making tool to select and evaluate alternatives through "pairwise comparison" in the context of hierarchical decision structure.
The results obtained from the analysis drawn by collecting the professional opinions of 5 experts for environmental sculptures are as follows:
1. The orders of establishment criteria priorities on environmental sculptures were harmony of environment > symbol > public > function. The harmony of environment was the most important priority because it showed the highest weight of criteria.
2. The alternative priorities of environmental sculptures were the meaning of work>setting place>social contribution >physical quality. The meaning of work showed the highest change in the weight of alternative.
3. The sensitivity analysis of environmental sculptures demonstrated that the rate of change in the alternative priorities of the public was stabilized although the criteria importance varied, while the harmony of environment, the symbol intimated and function priorities had their rates of weight changed if the criteria priorities were high.
9.
2000.12
서비스 종료(열람 제한)
Dust samples were collected from 17 middle and high schools in the Jeonju-city. Heavy metal concentrations were determined for the dry-deposited dusts from indoor and outdoor of classroom and playground of each sampling site. Concentrations of Cd, Cr, Cu, Ni, Pb and Zn in indoor's dusts were highly concentrated. Also heavy metal concentrations in outdoor's dusts were similar to that of indoor's dusts. Concentrations of Cd, Cu and Zn in the dusts were much higher than the world average contents in soil and environmental orientation value. These levels are similar to those of the dust samples at middle schools located at Kangseo-gu and Yangchon-gu, Seoul. Playground dusts in 6 schools exhibited the enhanced heavy metal pollution with a pollution index (by Kloke) greater than 1.0. Most indoor and outdoor dusts exhibited the enhanced heavy metal pollution with a pollution index (by Culbard et al.) greater than 1.0.
10.
2000.12
서비스 종료(열람 제한)
The purpose of this study was to evaluate the effects of Ca(OH)2 and CO2 additions on the corrosion of metal coupons (ductile iron, galvanized steel, copper and stainless steel). Corrosion rate and released metal ion concentration of ductile iron and galvanized steel was decreased by adjusting alkalinity, calcium hardness and pH with Ca(OH)2 & CO2 additions named CCPP (Calcium Carbonate Precipitation Potential) index control process. But the effects of Ca(OH)2 & CO2 additions on copper and stainless steel were less than those on ductile iron and galvanized steel. When ductile iron coupon was exposed to water treated with Ca(OH)2 & CO2 additions, the main components of corrosion product formed on its surface were CaCO3 and Fe2O3 or Fe3O4, which often reduce the corrosion rate by prohibiting oxygen transport to the metal surface.
11.
2000.12
서비스 종료(열람 제한)
The purpose of this experiment is to prepare ethylene propylene diene terpolymer(EPDM)/acrylonitrile butadiene rubber(NBR) blend which represents good environmental resistant properties including favorable oil and ozone resistance. With incorporation of EPDM, NBR and other ingredients, the rubber and chemical additives were mixed by mechanical method such as Banbury mixer and open 2-roll mill. Then rubber vulcanizates were manufactured by hot press and mechanical properties, oil and ozone resistance of the test specimens were measured.
The oil resistance and ozone resistance of EPDM and NBR, respectively, is remarkably improved by blending EPDM with NBR. The optimum results of oil and ozone resistant characteristics were obtained at EPDM/NBR(=25/75 wt%) composition ratio.
12.
2000.12
서비스 종료(열람 제한)
Separation of strontium ion from synthetic seawater in the contained liquid membrane permeator with two micro-porous films was performed. The permeator consisted of a liquid membrane and two cells for aqueous solutions. The liquid membrane consisted of D2EHPA(di-2-ethylhexyl-phosphoric acid) and DCH18C6 (dicyclohexano-18-crown-6), diluted to 30 vol % with kerosine and was trapped between two micro-porous hydrophilic films. This liquid membrane separated two aqueous solutions, one of which was synthetic seawater and the other of which was the stripping solutions consisting of 1㏖/L H2SO4 Solution.
The effects of various operating parameters on the extraction rate and equilibrium extraction ratio of strontium ion from synthetic seawater were experimentally examined. The addition of DCH18C6 to the D2EHPA solution caused synergy effect on the extraction of strontium ion. The permeator extracted strontium ion from synthetic seawater effectively with high membrane life time.
13.
2000.12
서비스 종료(열람 제한)
Attempts have been made to use Supercritical fluids for industrial purpose in a variety of fields and some of them, are already in practice. However, basic chemical properties of supercritical fluids have not been understood well.
The present paper presents the results of physicochemical studies on Supercritical fluids as well as the application of supercritical fluids to industry. The detail is as follows PCB and organic compounds.
