• 제목/요약/키워드: Commercial soil

검색결과 452건 처리시간 0.024초

지하 LPG저장공동 주변의 지하수위 강하 원인규명을 위한 파라미터추정 (Parameter estimation for identification on cause of drawdown around underground LPG storage cavern)

  • Han, Il-Yeong;Lee, Dae-Hyuck;Lee, Jung-Eun;Jung, Kwang-Pil
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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    • pp.76-80
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    • 1998
  • In order to identify the cause of ground water drawdown of a piezometer installed around the LPG storage cavern, parameter estimations were conducted by inverse and forward numerical models. An inverse model, SK-EST developed by SK Engineering & Construction Co., Ltd.(SKEC,1997) was performed to estimate the change of the hydraulic conductivity. It was verified by the commercial forward model, AQUA3D (VATNASKIL,1995). The simulation results showed that the hydraulic diffusivity of the rock mass between the piezometer and the cavern had been increased and the change rate of the hydraulic head had been abruptly increased in response to the change of the operation pressure. Finally the statistical analysis for observed data showed the increase of the change rate of the hydraulic head and thus proved the applicability of SK-EST.

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부산지역 강하먼지와 불용성 성분의 침적량에 관한 연구 (A Study on Bulk Deposition Flux of Dustfall and Insoluble Components in Pusan, Korea)

  • 김유근;박종길;문덕환;황용식
    • 한국환경과학회지
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    • 제10권3호
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    • pp.209-216
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    • 2001
  • Dustfall particles were collected by the modified American dust jar (wide inlet bottle type) at 6 sampling sites in Pusan area from March, 1999 to February, 2000. Thirteen chemical species (Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, Ni, Pb, Si, and Zn) were analyzed by AAS and ICP. The purposes of this study were to estimate qualitatively various bulk deposition flux of dustfall and insoluble components by applying regional and seasonal distribution. Dustfall amount of regional variations were found in order of coastal zone, industrial zone, commercial zone, agricultural zone and residential zone, and seasonal total dustfall had higher concentrations during spring for 6.741 ton/${km}^2$/season, lower concentrations during summer for 1.989 ton/${km}^2$/season, and annual total concentration was 17.742 ton/${km}^2$/year. The regional distributions of enrichment factor show well-defined anthropogenic metals (Cd, Cu, Pb, and Zn) at industrial and agricultural zone, and contribution rate of soil particles were found in order of summer, fall, winter and spring. Factor loading effects of chemical composition of dustfall were found in order of road traffic emission source and combustion processed source, industrial activity source, soil source and marine source.

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딸기탄저병의 시기별 발생과 감염경로 (Seasonal Occurrence and Infection Site of Strawberry Anthracnose)

  • 김승한;최성용;임양숙;윤재탁;최부술
    • 식물병연구
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    • 제8권1호
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    • pp.45-49
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    • 2002
  • 딸기탄저병의 발병특성은 정식 직후 격발하다가 시간이 지날수록 발병율이 감소하였으며, 11월 이후에는 발병이 감소하였다. 정식 직후에는 주로 런너로 침입하였으나 엽병 제거 후는 제거한 상처부위로 주로 침입을 하였다. 식물체의 부위별로는 런너에서 가장 강한 병원력을 보였으며 접종방법별로는 생장점 부위로 관주를 할 경우 가장 발병율이 높았다. 딸기탄저병에 의해 고사된 포기를 제거한 자리에 건전한 포기를 심었을 경우 옮겨 심은 포기에서는 발병이 되지 않았다.

다양한 경계조건을 가진 일차 반응 네트워크로 결합된 다종 오염물 거동 해석해 (Analytical Solution of Multi-species Transport Equations Coupled with a First-order Reaction Network Under Various Boundary Conditions)

  • 석희준;채병곤
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제16권6호
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    • pp.46-57
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    • 2011
  • In this study, analytical solution of multip-species transport equations coupled with a first-order reaction network under constant concentration boundary condition or total flux boundary condition is obtained using similarity transformation approach of Clement et al. (2000). The study shows the schematic process about how multi-species transport equations with first-order sequential reaction network is transformed through the similarity transformation approach into independent and uncoupled single species transport equations with first-order reaction. The analytical solution was verified through the comparison with popular commercial programs such as 2DFATMIC and RT3D. The analytical solution can be utilized in nuclear waste sites where radioactive contaminants and their daughter products occur and in industrial complex cities where chlorinated solvent such as PCE, TCE, and its biodegradation products produces. In addition, it can help the verification of the developed numerical code.

Synthesis of Nanoscale Zerovalent Iron Particle and Its Application to Cr(VI) Removal from Aqueous Solutions

  • Awad, Yasser M.;Abdelhafez, Ahmed A.;Ahmad, Mahtab;Lee, Sang-Soo;Kim, Rog-Young;Sung, Jwa-Kyung;Ok, Yong-Sik
    • 한국환경농학회지
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    • 제29권4호
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    • pp.402-407
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    • 2010
  • Zerovalent iron (ZVI) is one of the most commonly used metallic reducing agents for the treatment of toxic contaminants in wastewater. Traditional ZVIs are less effective than nanoscale ZVI (nZVI) due to prolonged reaction time. However, the reactivity can be significantly increased by reducing the size of ZVI particles to nanoscale. In this study, nZVI particles were synthesized under laboratory condition and their efficiency in removing hexavalent chromium (Cr(VI)) from aqueous solutions were compared with commercially available ZVI particles. The results showed that the synthesized nZVI particles (SnZVI) reduced >99% of Cr(VI) at the application rate of 0.2% (w/v), while commercial nZVI (CnZVI) particles resulted in 59.6% removal of Cr(VI) at the same application rate. Scanning electron micrographs (SEM) and energy dispersive spectra (EDS) of the nZVI particles revealed the formation of Fe-Cr hydroxide complex after reaction. Overall, the SnZVI particles can be used in treating chromium contaminated wastewater.

확률론적 응답면 기법을 이용한 저수지 제체의 침투수량 해석 (The Analysis of the Seepage Quantity of Reservoir Embankment using Stochastic Response Surface Method)

  • 봉태호;손영환;노수각;최우석
    • 한국농공학회논문집
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    • 제55권3호
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    • pp.75-84
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    • 2013
  • The seepage quantity analysis of reservoir embankment is very important for assessment of embankment safety. However, the conventional analysis does not consider uncertainty of soil properties. Permeability is known that the coefficient of variation is larger than other soil properties and seepage quantity is highly dependent on the permeability of embankment. Therefore, probabilistic analysis should be carried out for seepage analysis. To designers, however, the probabilistic analysis is not an easy task. In this paper, the method that can be performed probabilistic analysis easily and efficiently through the numerical analysis based commercial program is proposed. Stochastic response surface method is used for approximate the limit state function and when estimating the coefficients, the moving least squares method is applied in order to reduce local error. The probabilistic analysis is performed by LHC-MCS through the response surface. This method was applied to two type (homogeneous, core zone) earth dams and permeability of embankment body and core are considered as random variables. As a result, seepage quantity was predicted effectively by response surface and probabilistic analysis could be successfully implemented.

교반혼합체로 보강된 흙막이 벽체의 거동 분석 (Analysis of Behaviour of Earth Retaining Structure using Cement-mixing Method)

  • 김영석;조용상;강인철;김인섭
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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    • pp.1294-1300
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    • 2009
  • Recently, excavations in highly congest urban area have been increased. For the excavations conducted in extremely narrow spaces, we have been developing a novel soil reinforcement system of temporary retaining walls by using deep cement mixing method. The developing method installs largerdiameter ($\Phi$=300~500mm) and shorter reinforcement blocks than previous reinforcement system for mobilizing friction with soils, therefore it has advantages of not only shortening the length of reinforcement system but also reducing the amount of reinforcement. In this study, we performed a numerical analysis of the new reinforcement system by using a commercial finite element program, and evaluated the behavior of the reinforced retaining wall system under various conditions of the length, the diameter, the spacing, and the angle of the reinforcement system.

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철근콘크리트조 박스형 포상의 방호성능 평가 (The Study on Assessment of Protective Capacity of the Reinforced Concrete Box-type Artillery Positions)

  • 백종혁;김석봉;손기영;박영준
    • 한국군사과학기술학회지
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    • 제17권2호
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    • pp.275-281
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    • 2014
  • Although self-propelled artilleries are mobile equipment, they need their own covered-positions for survival against preemptive strikes. The most important military requirement is enough protective capacity against blast pressure caused by explosion. This paper aims to assess the protective capacity of the newly-placed concrete box-type artillery positions using accurate structural geometric models as well as soil-structure interaction analysis. The commercial program is used to model the structural geometry of the positions. In order to describe the correct wave propagation in the backfill along with soil-structure interaction, used parameters in shock equation of state are selected based on the related studies as well as theories and then their final results are verified with the ones calculated with empirical equations in the US Unified Facility Criteria. In sum, it could be concluded that the protective capacity of the newly-built positions satisfies the protective structural requirement.

Status of Community Drinking Water in Korea and Implications for Appropriate Management

  • Lee, Jin-Yong;Park, Youngyun;Kim, Nam-Ju;Jeon, Woo-Hyun
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제18권6호
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    • pp.56-68
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    • 2013
  • Community drinking water (CDW), mostly naturally flowing groundwater, plays important roles in supplying drinking water for urban and rural residents in Korea. Over 1,600 CDW facilities are distributed throughout the country, many of them situated in the outskirts of metropolitan cities. A large proportion of Korean people have become dependent on CDW for drinking due to a distrust of piped water's quality and a strong belief in the special medicinal effects of some CDWs. However, administrative and official management and the control of CDW facilities have been inadequate when compared with the strict examination and control of commercial bottled water, which is physically treated groundwater from deep bedrock aquifers. In this study, even though signs of anthropogenic contamination were not generally found, the tested chemical compositions of selected CDWs featured high enrichment of some constituents including Ca, Mg, Na, and HCO3 with natural origins such as water-rock interactions. Careless consumption of particular CDWs, which has no scientific basis, will not guarantee health improvement. Consequently, more intensive management of CDW facilities and a long-term interdisciplinary examination of the health effects of CDWs are needed to effectively protect people's health.

검거세미밤나방(Agrotis ipsilon )의 간이생물검정법에 의한 약제 감수성 (Convenient Bioassay Method and Insecticidal Susceptibility of the Black Cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae))

  • 이영수;이현주;최종윤;이상우;이영순;이희아
    • 한국응용곤충학회지
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    • 제60권2호
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    • pp.201-202
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    • 2021
  • 검거세미밤나방(Agrotis ipsilon)은 세계적으로 중요한 나비목 해충으로 유충이 토양 속에 서식하며 다양한 작물을 가해하기 때문에 생물검정에 어려움이 많다. 본 연구에서는 검거세미밤나방에 대한 간이생물검정법을 이용해 배추를 가해하는 검거세미밤나방의 시판 살충제에 대한 감수성을 검정하였다. 시험결과, 토양혼화처리제 6종, 토양관주처리제로 8종이 90% 이상의 살충활성을 보였다.