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
제19권 제1호 (2010년 1월) 13건
1.
2010.01
서비스 종료(열람 제한)
Only limited information is available on the measured exposure levels of residents according to the construction age of apartments. As such, present study was conducted to measure and to compare the bedroom, living-room, and outdoor air levels of MTBE and benzene, toluene, ethyl benzene and m,p-xylene(BTEX) in both newer and older apartments. For both newer and older apartments, all the compounds except for MTBE showed significantly higher levels in bedrooms or living-rooms as compared to the outdoor concentrations. The ratio of bedroom or living-room median concentration to outdoor concentration was close to 1 for MTBE, whereas it was larger than 1 for other target compounds. It was also found that the bedroom and living-room appeared to have similar indoor sources and sinks for BTEX, but not for MTBE. The median concentration ratios of the newer apartments to the older apartments ranged from 1.63 to 1.81, depending upon the compounds. In contrast, the MTBE concentrations did not differ significantly between the newer and older apartments, thereby suggesting that although newer buildings could emit more VOCs, this is not applicable to all VOCs. Conclusively, the findings of present study should be considered, when designing exposure studies associated with VOC emissions in buildings and/or managing indoor air quality according to construction age of buildings.
2.
2010.01
서비스 종료(열람 제한)
This pilot study evaluated fueling feasibility of sewage sludge, which contains a large amount of water content, by applying melting of thermoplastic polyethylene (PE). This study has identified a simultaneous achievement of drying and heating value improvement of the sewage sludge. The sewage sludge collected from a sewage sludge treatment plant during a winter period had a water content of 83.7 wt%, a combustible volatile content of 12.5 wt%, and an ash content of 3.8 wt%. The higher heating value (HHV) of the dried sewage sludge, before impregnation or coating of PE, was 4,600 kcal/kg. The collected sewage sludge was immersed into the melted PE solution, which had a HHV of 11,070 kcal/kg, and kept immersing with increasing reaction time. As the reaction (immersing or coating or impregnation) time increased, the water content of the sludge decreased. However, the HHV of the sludge increased with increasing the reaction time. The HHVs of the sewage sludge immersed or dipped into the melted PE solution for 15 min ranged from 6,780 to 8,170 kcal/kg with water content less than 7 wt%. This result indicates the melted PE solution can be utilized as an improvement technology for dryness and heating value of the sewage sludge with high water content. The sewage sludge impregnated or coated with melted PE can be utilized as potential fuel or energy resources.
3.
2010.01
서비스 종료(열람 제한)
To understand the initial changes in the microbial activities of wetland soil after construction, dehydrogenase activity (DHA) and denitrification potential (DNP) of soil from 1 natural wetland and 2 newly constructed wetlands were monitored. Soil samples were collected from the Daepyung marsh as a natural wetland, a treatment wetland in the West Nakdong River, and an experimental wetland in the Pukyong National University, Busan. The results showed that the DHA of the natural wetland soil was 6.1 times higher than that of the experimental wetland and similar to that of the treatment wetland 6 months after wetland construction (fall). Few differences were observed in the DNP between the soil samples from the natural wetland and 2 constructed wetlands four months after wetland construction (summer). However, 6 months after the construction (fall), the DNP of the soil samples from the natural wetland was 12.9 times and 1.8 times higher than that of the experimental wetland and the treatment wetland, respectively. These results suggested that the presence of organic matter as a carbon source in the wetland soil affects the DHA of wetland soil. Seasonal variation of wetland environment, acclimation time under anaerobic or anoxic wetland conditions, and the presence of carbon source also affect the DNP of the wetland soil. The results imply that the newly constructed wetland requires some period of time for having the better contaminant removal performance through biogeochemical processes. Therefore, those microbial activities and related indicators could be considered for wetland management such as operation and performance monitoring of wetlands.
4.
2010.01
서비스 종료(열람 제한)
A system coupled the prognostic WRF mesoscale model and CALMET diagnostic model has been employed for predicting high-resolution wind field over complex coastal area. WRF has three nested grids down to 1km during two days from 24 August 2007 to 26 August 2007. CALMET simulation is performed using both initial meteorological field from WRF coarsest results and surface boundary condition that is Shuttle Radar Topography Mission (SRTM) 90m topography and Environmental Geographic Information System (EGIS) 30m landuse during same periods above. Four Automatic Weather System (AWS) and a Sonic Detection And Ranging (SODAR) are used to verify modeled wind fields. Horizontal wind fields in CM_100m is not only more complex but better simulated than WRF_1km results at Backwoon and Geumho in which there are shown stagnation, blocking effects and orographically driven winds. Being increased in horizontal grid spacing, CM_100m is well matched with vertically wind profile compared SODAR. This also mentions the importance of high-resolution surface boundary conditions when horizontal grid spacing is increased to produce detailed wind fields over complex terrain features.
5.
2010.01
서비스 종료(열람 제한)
When the Juam multipurpose dam which is connected with existing large water supply facilities is finished, water environment is changed from stream to lake. The changed quality of water should be examined. In this study, the result of water quality forecasting is analysed and an effective management plan of water quality is presented. In this study, the WASP5 model that is a dynamic water quality simulation model was selected to forecast the water quality. This model forecasts movement of change of pollutants. For an application of the model, the subject areas were divided into seventeen sub-areas by considering change temperature depending measuring points and on depth of water. Meteorological data collected by the meteorological observatory and data about quality measured by the Korea Water Resources Development Corporation were used for an operation of the model. As a result of quality examination through quality data and estimated pollutant loading, the water quality environment criterion was grade Ⅱ and the nutritive condition was measured as meso-graphic grade. In this study, an effective management was planned to improve water quality by reducing pollution load. According to the result of examination, when more than 30% of BOD was reduced it was recorded that the environment standard of water quality was improved to the second grade.
6.
2010.01
서비스 종료(열람 제한)
This study was to examine the characteristics of wirdbirds habitat for improvement plan in green corridor. The target site, Gangseo-gu artificial green corridor was set up with the structure in which small scale of core green space with Goongsan and Yeomchang neighborhood parks in urbanized city was connected with the artificial green space with Gongamnaru, Hwanggeumnae neighborhood parks with 28∼42.5 m in width. Wild birds six∼eleven species; Dendrocopos spp, Paradoxornis webbiana, Parus major, Phasianus colchicus, etc. were observed in core green, but wild birds of two∼five species: Columba livuia, Passer montanus, Pica pica, Hypsipetes amaurotis, etc. were observed in artificial green space. Thus wild birds of artificial and generalist species only moved in artificial green space. The artificial green space where vegetation structure was consisted of single-layer with poorness chose target species laying stress on generalist species and edge species of Parus major, P. palustris, Paradoxornis webbiana etc. for short-term and interior species of Dendrocopos major, Picus canus, etc. for long-term. The result suggested enhancement methods for target species's habitat in green corridor: to secure at least a corridor 30 meters in artificial corridor, to secure ecological pond, to offer the various shelterer and environment of prey-resources through the multi-layer structure.
7.
2010.01
서비스 종료(열람 제한)
In this study, we analyzed the pulse-duration, pulse-interval and peak-frequency of echolocation call in three species as Rhinolophus ferrumequinum, Pipistrellus abramus, and Myotis macrodactylus. The peak frequency and pulse duration for above mentioned species were 69 kHz, 47 kHz and 49 kHz and 69.39±8.76 ms, 4.95±0.77 ms and 3.09±0.48 ms for R. ferrumequinum, P. abramus and M. macrodactylus, respectively. The pulse intervals for R. ferrumequinum, P. abramus and M. macrodactylus were 103.61±9.05 ms, 67.59±3.47 ms and 66.35±4.96 ms, respectively. The pulse pattern of R. ferrumequinum was setting into a short FM call and linked to long CF call and went through the short FM call again. The pulse pattern of M. macrodactylus was comprised with serial short FM call and the CF call was not checked up in accordance with the spectrogram analysis. The long FM call and short CF call got join together for the P. abramus and the peak frequency was checked up at the pulse ending as CF call.
8.
2010.01
서비스 종료(열람 제한)
Today’s fundamental purpose of environmental education is to fulfill people’s desire of living in a pleasant environment and at the same time promoting individualistic and collective environmentally friendly behaviors. In order to achieve these purposes, it is very important that each person holds an environmentally friendly mind that constantly tries to preserve and protect the environment which should be acquired through experiencing the importance of the environment. In order to increases the sense of attachment of people and the natural environment, the direction of environmental education should carry out education on environment related knowledge and the condition of environment damage side by side. The direction of environmental education should consider the cultivating student’s awareness for active participation on matters related to the environment and to change their behaviors towards the environment. This study has tested the effect of reflective writing activities about the environment on the environmental sensitivity and willingness to act of 5th grade primary school students. For the sole purpose of this study, 70 students out of 141 5th graders of M Primary School were divided as the experimental group, and another 71 students were divided as the control group. The experimental group participated in 10 activities in where they were asked to express their thoughts and feelings in writing regarding 10 environmental problems occurring near the M Primary School. The control group participated in 10 environmental education lectures focusing on the lecturer. The results were as following.
First, the reflective writing activities about the environment were effective in the environmental sensitivity of primary school students. Second, the reflective writing activities about the environment can affect the environmental willingness to act of primary school students. Third, there was a statistically significant correlation between environmental sensitivity and environmental willingness to act.
9.
2010.01
서비스 종료(열람 제한)
Cool island intensity urban green space was investigated based in Dalsung Park, that is one of the largest parks in Daegu. Cool island intensity(CII), which is defined as the temperature difference between the green space and its surrounding built-up areas, shows time variations. A through-year measurement(2008-2009) of ground level air temperature revealed seasonal variation and relationship to the atmospheric condition of CII. The temperature variation in the park and the reference downtown Daegu was as same order as CII. The noontime CII is larger in summer than that in winter due to the leaf fall of the park trees. On the other hand, seasonal variation of nighttime CII is not so clear. The nighttime CII was larger under the stable atmosphere.
10.
2010.01
서비스 종료(열람 제한)
The separation of TiO2 wastewater carried out by an electrocoagulation/flotation process, which had various operating parameters. The effect of electrode material (aluminum and four dimensionally stable electrode), applied current (0.07∼0.5 A), electrolyte concentration (0∼1 g/L), solution pH (3∼11), initial turbidity (1000∼20000 NTU) and suspended solid concentration (5000∼25000 mg/L) were evaluated. Turbidity removal efficiency of the soluble anode (aluminum), which could produce metal ions, was higher than that of the dimensionally stable electrode. Considering operation time, turbidity removal and electric power, optimum current was 0.19 A. The more NaCl dosage was high, the less electric power was required. However, optimum NaCl concentration was 0.125 g/L considered removal efficiency, operation time and cost. Initial TiO2 concentration did not affected turbidity removal on the electrocoagulation/ flotation operation. The electrocoagulation/flotation process was proved to be a very effective separation method in the removal of TiO2 from wastewater.
11.
2010.01
서비스 종료(열람 제한)
The biodegradable oil absorption resin was prepared by the suspension polymerization of the modified starch and 2-ethylhexyl acrylate (2-EHA). The highest oil-absorption capacity of B-PEHA prepared showed at the condition of the modified starch content of 10 g and ethyleneglycol dimethacrylate (EGDMA) of 0.133 wt%. Its maximum oil absorption capacity per g of oil absorber was chloroform 30.88 g, toluene 19.75 g, xylene 18.78 g, tetrahydofuran (THF) 15.96 g, octane 11.43 g, hexane 9.5 g diesel oil 12.80 g, and kerosene 13.79 g, respectively. The biodegradation of poly-2-ethylhexylacrylate (B-PEHA) determined by enzymatic hydrolysis showed approximately 17∼20%. The results showed that the preparation of the biodegradable oil absorption resin is available using the modified starch.
12.
2010.01
서비스 종료(열람 제한)
The objective of the paper is to experimentally investigate the compressive strength of the concrete incorporating fly ash. Ordinary Portland cement(OPC). Water to binder ratio(W/B) ranging from 30% to 60% and curing temperature ranging from -10℃∼65℃ were also adopted for experimental parameters. Fly ash was replaced by 30% of cement contents. According to the results, strength development of concrete contained with fly ash is lower than that of plain concrete in low temperature at early age and maturity. In high curing temperature, the concrete with fly ash has higher strength development than that of low temperature regardless of the elapse of age and maturity. Fly ash can have much effect on the strength development of concrete at the condition of mass concrete, hot weather concreting and the concrete products for the steam curing.
13.
2010.01
서비스 종료(열람 제한)
Urban watershed can be found in the visible changes in technology, the most realistic satellite images is to use the data. Satellite image data on the indicators for progress on the nature of the change of land use is consistent and repetitive information, regular observation makes possible the detailed analysis of space-time. These remote sensing techniques and the type of course and, by using the time series history, the past, the dynamic model and the randomized prediction methodology for the conversion process if the city and river basin cooperation of the space changes effectively will be able to extrapolate.
For each of the main changes in river flow, depending on the area of urbanization as determined according to reproduce the duration of the relationship between the urbanization of the area and runoff can be represented as a linear polynomial expression was, if a linear expression in the two fast slew rate of 0.858 to 0.861 showed up, and fast slew rate of 0.934 to 0.974 for the polynomial are reported.
Change of land use changes in the watershed of the flow is one of the most affecting elements. Therefore, changes in land use of the correct classification of rivers is a more accurate calculation of the amount of the floodgate. In particular, using the Landsat images through the image of the land use category, land use past data and calculated using the Markov Chain model and predict the future land use plan in the water control project will be used for large likely.
