• 제목/요약/키워드: low-pollution

검색결과 1,278건 처리시간 0.032초

인터로킹 블록포장의 저속도로 적용성 평가 (Performance Evaluation of Interlocking Block Pavement for Low Speed Highway)

  • 임무광;류성우;이병태;조윤호
    • 한국도로학회논문집
    • /
    • 제16권2호
    • /
    • pp.1-9
    • /
    • 2014
  • PURPOSES : This study aims to evaluate the performance of interlocking block pavement system for low speed highway. METHODS : Through on-site monitoring, environmental impact assessment of interlocking block pavement such as heat island reduction, traffic safety, noise pollution were evaluated as compared with asphalt pavement. Also the pavement condition and roughness were evaluated according to performance period. RESULTS : Surface temperature of interlocking block pavement was about 7 degree lower than asphalt pavement in midsummer. Compared to asphalt pavement, vehicle speed reduction effect of interlocking block pavement was about 2kph. For low speed driving, the noise pollution was measured at a similar level for both asphalt and interlocking block pavement. After 42month service period, the breakage of block was only 0.24% for the whole surveyed area. IRI of interlock block pavement was estimated within the range of 5~8m/km. CONCLUSIONS : Depending on the performance monitoring results such as heat island reduction, providing traffic safety and keeping a good pavement condition for a long service period, it assures that interlocking block pavement was applicable for low speed road.

PEMFC 단위 셀의 제작 및 저전압.저전력 시스템 설계에 관한 연구 (A Study on Manufacture and Design of Low Voltage.Low Electric Power System by PEMFC Single cell)

  • 류윤심;안호균;서정랑;김성훈;이창호
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 2007년도 추계학술대회 논문집
    • /
    • pp.193-195
    • /
    • 2007
  • These days, to change the new & renewable energy change the subject because environmental pollution and exhausted fossil power. The most notable Fuel cells by one of the new & renewable energies are one of very useful power conversion sources. Their advantages are low environmental pollution, highly efficient power generation, diversity of fuels (natural gas, LPG, methanol and naphtha), and reusability of exhaust heat, modularity, and faster installation. PEMFC by one of the Fuel Cells is the energy of new technology which is produced by the electric chemical reaction directly. The essential composition elements of PEMFC stack are membrane electrode assembly (MEA), catalyst, Bipolar Plate. Under the this study, know-how is manufacturing single cell of PEMFC and Study design of Low Voltage, Low Electric Power System by PEMFC Single Cell.

  • PDF

대기오염 노출이 첫 출산아 저체중에 미치는 영향에 관한 연구 -서울지역 1999년~2003년 출생코호트를 중심으로- (Air Pollution Exposure and Low Birth Weight of Firstborn Fetus -A Birth Cohort Study in Seoul, 1999-2003-)

  • 조용성;손지영;이종태
    • 한국환경보건학회지
    • /
    • 제33권4호
    • /
    • pp.227-234
    • /
    • 2007
  • Recent epidemiologic studies show that gestational exposure to air pollution adversely affects pregnancy outcomes including low birth weight in preform birth. In this study, we evaluated the effect of air pollutants on LBW (low birth weight) on firstborn fetus throughout the gestational period using the birth cohort between 1999 and 2003 in Seoul. Using birth cohort data from the National Statistics Office of Korea we identified 288,346 firstborn births (excluded missing data on lack of information for birth weight and discordance between residential and certificated address from a total of 316,451) during 1999 to 2003 with complete covariate (gender, parity, date of birth, gestational age, parental age and educational level, maternal occupation etc.) and maternal residential history data. Our subjects were defined as more than 37 weeks and less than 44 weeks of completed gestation and we identified 5,457 persons (1.89%) by low birth weight (<2.5 kg) in this study. Using logistic regression, we estimated the risk of mean (entire pregnancy and trimester period) air pollution concentrations for CO, $O_3,\;PM_{10},\;NO_2\;and\;SO_2$. In terms of trimester-specific exposure, we found that some air pollutants exposure in each trimester would increase the risk for LBW. Results also showed that the effect size of air pollutants exposure during the first and third trimester is higher than during the second trimester. In all trimester, the estimated risk of LBW was 1.831 (95% CI=1.573-2.132) with unit increase for CO, 1.139 (95% CI=1.107-1.172) for 50, and 1.009 (95% CI=1.001-1.017) for $O_3$. Our results suggest that exposure during the gestation period to relatively low levels of some air pollutants may be associated with a reduction in birth weight on first-born fetus. These findings implicate the effective risk management strategies should be applied to minimize the public health impacts for pregnant women.

국내 9기 석조문화재의 생물오염피복도 및 기중조류 군집 (The Community of Aerial Algae and the Biological Pollution Coverage at 9 Stone Cultural Heritages in Korea)

  • 김용진;김옥진;이옥민
    • 보존과학회지
    • /
    • 제27권2호
    • /
    • pp.145-154
    • /
    • 2011
  • 본 연구는 2008년 6월에서 11월까지 국내 9기의 석조문화재를 대상으로 색에 따른 오염등급의 평가와 생물오염피복도를 조사하였다. 생물오염피복도는 홍천물걸리삼층석탑, 수타사삼층석탑 및 수타사홍우당부도에서 90% 정도로 나타났으며, 선태류의 생물오염피복도가 15~23%의 범위로 생물오염이 가장 심한 것으로 나타났다. 색에 따른 생물오염등급은 괘석리사사자삼층석탑, 수타사삼층석탑, 수타사홍우당부도가 등급 5로 오염등급이 가장 높았으며, 여주창리삼층석탑이 등급 2로 양호하게 나타났다. 상관분석 결과 생물오염등급과 지의류의 생물오염피복도는 높은 상관성(r=0.91)을 나타냈지만, 기중조류와 선태류의 생물피복도와는 상관성은 낮게 나타나 이에 대한 보완이 필요할 것으로 판단된다. 각 출현종과 생물오염피복도(선태류, 지의류, 기중조류)의 상관분석결과 선태류의 생물피복도와 Cosmarium decedens, Chlorella ellipsoidea, Anabaena fertilissima, Botryococcus braunii, Chroococcus turgidus, Navicula cryptocephala 및 Xenococcus acervatus가 상관계수 0.56~085의 범위로 높은 상관성을 나타냈다. 지의류의 생물피복도는 Trebouxia sp. 및 Chroococcus varius와 상관계수 0.50 및 0.43으로 나타났으며, 기중조류의 생물오염피복도는 Achnanthes laterostrata 및 Ulothrix zonata와 상관계수 0.76 및 0.57의 상관성을 나타냈다. 생물오염피복도와 상관성이 높은 기중조류는 출현 경향성이 대체로 뚜렷하게 나타나, 지표종으로 유용하게 사용될 수 있을 것이라 판단된다.

생물학적 처리기술을 이용한 대기오염 제어 (Biotreatment Technologies for Air Pollution Control)

  • 원양수
    • 청정기술
    • /
    • 제13권1호
    • /
    • pp.1-15
    • /
    • 2007
  • 미생물을 이용하여 생물분해 가능한 휘발성유기물질과 악취물질을 처리하는 생물학적 대기오염처리 기술은 기존의 일반적으로 사용되고 있는 방법에 비해 상대적으로 최근에 개발된 방법이다. 생물학적 방법에 의한 대기오염물질 처리는 기존의 처리방법을 대체할 수 있는 방법으로 각광을 받고 있다. 생물학적 처리방법은 유기화합물 또는 악취가 포함된 저농도 고유량의 공기를 처리하는데 효과적이다. 생물학적 처리방법은 기존의 소각 또는 흡착 방법에 비해 여러 장점을 가지고 있다. 주요 장점으로 처리비용이 저렴하고, 2차 오염물질이 발생되지 않으며, 화학물질이 사용되지 않고, 에너지 사용이 적으며, 상온에서의 운전 등이다. 생물학적 방법중 생물여과법, 생물살수여과법, 생물세정법 세가지 방법이 널리 이용되고 있다. 이들 방법중 생물여과법이 가장 많이 이용되고 있으나 실제 적용에 있어 여러 제약이 있어 이를 해결하기 위한 생물학적 방법들에 대한 연구가 수년 전부터 수행되어 왔다. 생물살수여과법은 생물여과법에 비해 다소 복잡하나 난분해성 물질이나 분해과정에서 산이 생성되는 경우 효과적으로 이용될 수 있다. 본 연구에서는 대기오염제어를 위한 생물여과법, 생물살수여과법, 생물세정법의 기본원리와 이론 및 실용적 내용을 다루었다. 특히 생물학적 방법들의 운전 인자와 성능에 미치는 영향인자 및 비용평가 등에 대해 조사 분석하였으며, 생물살수여과법에 대해서는 좀 더 집중적으로 고찰하였다.

  • PDF

토양측정망에 의한 충북지역 토양오염도 (A Study on Soil Pollution Quality of Chungbuk Province by Soil Network)

  • 김재용;박선희
    • 환경위생공학
    • /
    • 제16권4호
    • /
    • pp.77-89
    • /
    • 2001
  • The research is intended to evaluate the soil pollution quality of Chungbuk province with Soil Network which is executed every year. The survey executed with Soil Network in 1999 represented that the soil quality of Chungbuk province was relatively good as the average concentrations of contaminants in soil were Cd: 0.146 mg/17g, Cu: 3.143 mgHg, As: 0.636 mg/kg, Hg: 0.012 mg/kg, Pb): 4.505 mg/kg, $Cr^{+6}$ not detected, and the average pH was 6.1. The reckoned soil Pollution score (SPS) of Chungbuk province has been shown much low SPS distribution in the range from 1.6 to 141.7, average 31.0. However, it has been represented relatively high SPS distribution at Chungju, Tanyang, and Chinchon, respectively, It also huts represented high SPS distribution not only at agricultural area and waste area for the Pollution sources but at a paddy field and dry field for land use. The classification of soil pollution class(SPC) based on soil pollution score(SPS) was SPC 1 under 100 of SPS at 212 areas which were 98.6% of total 215 areas and SPC 2 over 100 of SPS at only three area left. There was no area exceeding soil pollution value among the whole Soil Network areas investigated, and the whole average for each items was much lower level th퍼n soil Pollution value was. When the average concentration of heavy metals and the average pH in soil of Chungbuk province are compared with the natural contents of that in Korea, the research is concluded that the average concentration of heavy met is relatively similar to the natural contents of that and the average pH in soil of Chungbuk province is a little higher than the natural contents of that. From this method, soil quality of most of the Soil Network area was estimated to be healthy.

  • PDF

청주 지역 중학생 자모들의 환경오염 방지에 대한 의식과 실천 연구 (Recognition and Practice of middle school students' mothers on Prevention of Environmental Pollution in Cheong-ju)

  • 김기남;권수애
    • 한국환경교육학회지:환경교육
    • /
    • 제8권1호
    • /
    • pp.66-80
    • /
    • 1995
  • The purpose of this study was to investigate the housewives's recognition and practice on prevention of environmental pollution. The subjects of this study were 250 housewives, school students' mothers, living in Cheong-ju. Major findings were as follows: 1. In washing their faces and brushing their teeth, they saved the water very well, but in taking bath, washing the dished, using the water of the lavatory they did not save the water so well. 2. The kinds of the cleansers differed in taking a bath, washing the hair, and doing the laundry respectively : what they use most was hard soaps in taking bath, liquid cleansers mixed with shampoo and linse in washing the hair, and synthetic powder detergent in laundrying. They used more synthetic detergent than natural soaps, which is known to be a cause of water pollution. Especially, when they cleansed, they did not use a measuring cup. It resulted in the waste of detergent and accelerating of water pollution. Therefore, the environmental education for them was very urgently needed. 3. In handling domestic waste, the separate collection rate of empty bottles and old newspapers was very high, but that of used phone-call cards and used batteries was extremely low. It was truly nessesary to educate and step up publicic activities on the separate collection of phone-call cards and batteries caused environmental pollution. 4. The housewives had much knowledge about environmental pollution, but they did not practice it so well in their home. 5. The housewives made more effort than their children in preventing environmental pollution and saving resources. In conclusion, what is most important for solving environmental problem was for each citizen to make an effort to prevent environmental pollution, and the government's support and producing the atmosphere of the society for this was really needed.

  • PDF

Absorption properties and size distribution of aerosol particles during the fall season at an urban site of Gwangju, Korea

  • Park, Seungshik;Yu, Geun-Hye
    • Environmental Engineering Research
    • /
    • 제24권1호
    • /
    • pp.159-172
    • /
    • 2019
  • To investigate the influence of pollution events on the chemical composition and formation processes of aerosol particles, 24-h integrated size-segregated particulate matter (PM) was collected during the fall season at an urban site of Gwangju, Korea and was used to determine the concentrations of mass, water-soluble organic carbon (WSOC) and ionic species. Furthermore, black carbon (BC) concentrations were observed with an aethalometer. The entire sampling period was classified into four periods, i.e., typical, pollution event I, pollution event II, and an Asian dust event. Stable meteorological conditions (e.g., low wind speed, high surface pressure, and high relative humidity) observed during the two pollution events led to accumulation of aerosol particles and increased formation of secondary organic and inorganic aerosol species, thus causing $PM_{2.5}$ increase. Furthermore, these stable conditions resulted in the predominant condensation or droplet mode size distributions of PM, WSOC, $NO_3{^-}$, and $SO{_4}^{2-}$. However, difference in the accumulation mode size distributions of secondary water-soluble species between pollution events I and II could be attributed to the difference in transport pathways of air masses from high-pollution regions and the formation processes for the secondary chemical species. The average absorption ${\AA}ngstr{\ddot{o}}m$ exponent ($AAE_{370-950}$) for 370-950 nm wavelengths > 1.0 indicates that the BC particles from traffic emissions were likely mixed with light absorbing brown carbon (BrC) from biomass burning (BB) emissions. It was found that light absorption by BrC in the near UV range was affected by both secondary organic aerosol and BB emissions. Overall, the pollution events observed during fall at the study site can be due to the synergy of unfavorable meteorological conditions, enhanced secondary formation, local emissions, and long-range transportation of air masses from upwind polluted areas.

저오염 사료의 급여에 의한 잉어의 성장과 질소 및 인 배설량 (Growth and Excretion of Nitrogen and Phosphorus of Israeli Strain of Carp(Cyprinus carpio) Fed a Low Pollution Diets)

  • 김정대;이종윤;김광석;이승복;최낙중;김응오
    • 한국양식학회지
    • /
    • 제11권1호
    • /
    • pp.39-48
    • /
    • 1998
  • Growth performance and excretions of nitrogen (N) and phosphorus (P) were investigated with carp (Cyprinus carpio) with carp (Cyprinus carpio) grower fed a low pollution diets (A and B) and commercial ones (Com-1 and Com-2). A recirculated rearing system (Exp. I) and a floating net cage system (Exp. II) were employed for two feeding trials in which fish having an initial body weight of 152g and 193g were fed for 41 an 39 days, respectively. The highest weight gain, daily growth rate and protein efficiency ratio were found (P<0.05) in fish fed diet A containing 10% fish meal and 2% monocalcium phosphate (MCP) for both experiments. They also showed the lowest feed conversion ratio and daily feeding ration among treatments. Fish fed diet B containing 10% fish meal, 5% fish protein concentrate and 1% MCP showed weight gain and FCR more improved (P<0.05) than those fed commercial diets. In all groups, whole body cmpositions were not greatly different among treatment, and protein and P contents in final fish ranged from 14.3 to 15.6% and from 0.39 to 0.48%, respectively. Fish fed diet A excreted the least N which were 38.3 in Exp. I and 39.6g/kg gain in Exp. II. However, the values found in fish fed two commercial diets amounted to 59.1 and 58.9g, respectively. A significant decrease in P excretion was also found in fish groups fed diets A and B. In Exp. I, a reduction of 53.4% was shown in fish fed diet A, compared to the averaged value (18.5g P/kg gain) of two commercial groups. In Exp. II conducted using the floating net cages, fish fed diet B excreted the least P (8.6g/kg gain) among the treatment, which was followed by fish fed diet A, showing 48.6% reduction compared to the average value (18.5g/kg gain) for fish fed two commercial diets. The present results clearly showed that N and P excretions from fish culture could be significantly reduced by using the low pollution diet.

  • PDF