• Title/Summary/Keyword: Water movement

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Rainfall Runoff Characteristics and Risk Assessment of Agro-chemicals Used in Golf Links (골프장에 산포되는 농약의 강우유출특성과 risk assessment)

  • ;Tohru Morioka
    • Journal of Environmental Science International
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    • v.4 no.1
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    • pp.19-28
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    • 1995
  • A rainfall runoff model described in this paper which is based on Basin- wide Ecological Model(BAWEM) calculates the fate of afro-chemicals in a watershed located of golf links. The rainfall runoff coefficients of afro-chemicals, which are the dominant parameters to predict the movement of agro-chemicals from soil and turfgrass to downstream water, are estimated. Also, the model is used to estimate the level of health risks the residents around golf links are exposed to. The fidelity of rainfall runoff model of afro-chemicals was validated by the observed data obtained during rainy period. The calculated results from this model were found to be in the same order of that of the observed. The rainfall runoff coefficients of four agro-chemicals used in golf links were 5.4$\times$$10^{-3}$, 1.9$\times$$10^{-3}$, 3.0$\times$$10^{-4}$ and 4.4$\times$$10^{-3}$ for flutolanil, isoprothiolane, chlorpyrifos and simazine, respectively The health risk level to the residents around golf links is evaluated to be rather low:the ratio of estimated dose through drinking water to the 10% of ADI(Acceptable Daily Intake) value or VSD for 10-a life time risk varied in the range of 0.005~0.04 and 0.003~0.11, respectively, for both the annual mean and maximum monthly mean cases.

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Analysis of Influence Factors for Remediation of Contaminated Soils Using Prefabricated Vertical Drains (연직배수재를 이용한 오염지반 복원의 영향인자 분석)

  • Park, Jeongjun;Shin, Eunchul
    • Journal of the Korean GEO-environmental Society
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    • v.9 no.2
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    • pp.39-46
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    • 2008
  • Due to the growth in industrialization, potential hazards in subsurface environments are becoming increasingly significant. The extraction of the contaminant from the soil and movement of the water are restricted due to the low permeability and adsorption characteristics of the reclaimed soils. There are a number of approaches to in-situ remediation that are used in contaminated sites for removing contaminants. These include soil flushing, dual phase extraction, and soil vapor extraction. Among these techniques, soil flushing was the focus of the investigation in this paper. Incorporated technique with PVDs has been used for dewatering from fine-grained soils for the purpose of ground improvement by means of prefabricated vertical drain systems. The laboratory model tests were performed by using the flushing tracer solutions for silty soils and recorded the tracer concentration changes with the elapsed time and flow rates. The modeling was intended to predict the effectiveness and time dependence of the remediation process. Modeling has been performed on the extraction, considering tracer concentration and laboratory model test characteristics. The computer model used herein are SEEP/W and CTRAN/W, this 2-D finite element program allows for modeling to determine hydraulic head and pore water pressure distribution, efficiency of remediation for the subsurface environment. It is concluded that the coefficient of permeability of contaminated soil is related with vertical velocity and extracted flow rate. The vertical velocity and extracted flow rate have an effect on dispersivity and finally are played an important role in-situ soil remediation.

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Ecological Green Roofs in Germany

  • Kohler, Manfred
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.7 no.4
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    • pp.8-16
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    • 2004
  • The industrialization of central Europe more than 100 ago marked the beginning of densely concentrated buildings in quickly growing cities. A cheap type of roofing material of that time was tar. But it was dangerous because it was high inflammable. Then some roofer had a splendid idea. They used sandy material as a final layer atop the impermeable tar layer. These roofs were much more fire resistant than the typical roofs. In this sandy layer some plant species began to grow spontaneously. This was the beginning of the green roof history of modern Europe. A number of these green roofs survived both world wars. In the early 80's in Berlin alone, 50 such buildings existed and they continued to be waterproof until the present day. Since the 1992 Earth Summit of 1992 in Rio de Janeiro(http://www.johannesburgsummit.org/html/basic_info/unced.html) the term "sustainable development" became of central interest of urban designers. In city regions green roofs had become synonymous with this term. With a small investment, long-lasting roofs can be created. Further back in history, more exciting examples of green roofs can be found. The hanging gardens of antiquity are well-known. There are also green roofs built as insulation against cold and heat all over the world. For over 20 years, roof greening in central Europe has been closely examined for various reasons. Roof greening touches several different disciplines. Of primary interest is the durability of the roofs. But ecologists are also interested in green roofs, for instance in biodiversity research. The beneficial effect of greening on water proofing was also proven. For some time, the issue of fire protection was investigated. According to tests, green roofs received a harsh careful rating. Their fire protective property is considered similar to that of tile roofs. Another recent impulse for the green roof movement in Germany has come from the evident improvement of storm water retention and the reduced burden on the sewer system. The question of whether and how much energy green roofs can save has become an urgent question. The state of the research and also various open questions from a central European point of view will be discussed in the context of international collaboration. Apart from academic considerations, those who involve themselves in this issue take a predominantly positive view of the numerous existing green roofs in Germany. In some cities, green roofs are the typical construction technique for new buildings. A few outstanding examples will conclude this review. In Germany, about 20 companies, some of which operate internationally, specialize in green roof consulting. Learning from each other in an open-ended way with respect to different construction techniques and applications in various climatic regions can only be accomplished through such international collaboration as is taking place here.

Quantitative Deterioration Assessment and Microclimatic Analysis of the Gyeongju Seokbinggo (Ice-storing Stone Warehouse), Korea (경주석빙고의 정량적 훼손도 평가와 미기후환경 분석)

  • Kim, Ji-Young;Lee, Chan-Hee;Lee, Myeong-Seong
    • Journal of Conservation Science
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    • v.25 no.1
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    • pp.25-38
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    • 2009
  • The Gyeongju Seokbinggo (Treasure No. 66) is an ice-storing stone warehouse, consisting mainly of alkaligranite which shows milky white color and medium-grained textures with drusy cavities. As results of deterioration assessment, the deterioration rates were determined as crack (12.5%), disjoining (6.7%), breaking-out (25.1%), exfoliation (20.9%), efflorescence (6.5%), brown discoloration (9.8%), darkgray discoloration (2.0%) and biological discoloration (36.5%). Comprehensive physical deterioration rate and discoloration rate were calculated as 43.7% and 68.7%, respectively, that indicates the Seokbinggo has been severely weathered. Indoor relative humidity was above 90% except in winter season. Indoor microclimate was hardly fluctuating although indoor microclimate was dependent on the outdoor climate. The main cause of deterioration was high relative humidity and a long time of wetness due to penetration of rain, underground water and condensation. It was identified that the water brought out biological discoloration, dissolution of minerals, structural movement and efflorescence, and the dust from the ground soil in front of the entrance accelerated brown and dark gray discoloration on the stone surface.

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Simulation for the Estimation of Design Parameters in an Aquifer Thermal Energy Storage (ATES) Utilization System Model (대수층 축열 에너지(ATES) 활용 시스템 모델의 설계인자 추정을 위한 시뮬레이션)

  • Shim Byoung-Ohan
    • Journal of Soil and Groundwater Environment
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    • v.10 no.4
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    • pp.54-61
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    • 2005
  • An aquifer thermal energy storage (ATES) system can be very cost-effective and renewable energy sources, depending on site-specific parameters and load characteristics. In order to develop the ATES system which has certain hydrogeological characteristics, understanding the thermohydraulic process of an aquifer is necessary for a proper design of an aquifer heat storage system under given conditions. The thermohydraulic transfer for heat storage was simulated according to two sets of simple pumping and waste water reinjection scenarios of groundwater heat pump system operation in a two-layered aquifer model. In the first set of the scenarios, the movement of the thermal front and groundwater level was simulated by changing the locations of injection and pumping wells in a seasonal cycle. However, in the second set the simulation was performed in the state of fixing the locations of pumping and injection wells. After 365 days simulation period, the shape of temperature distribution was highly dependent on the injected water temperature and the distance from the injection well. A small temperature change appeared on the surface compared to other simulated temperature distributions of 30 and 50 m depths. The porosity and groundwater flow characteristics of each layer sensitively affected the heat transfer. The groundwater levels and temperature changes in injection and pumping wells were monitored and the thermal interference between the wells was analyzed to test the effectiveness of the heat pump operation method applied.

Hemipelvectomy in a Cat with Obstipation (심한 변비를 보이는 고양이에서 반골반절제술을 이용한 외과적 치료 증례)

  • Yoon, Hun-Young;Kim, Kyung-Hee;Jeong, Soon-Wuk
    • Journal of Veterinary Clinics
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    • v.30 no.2
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    • pp.119-122
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    • 2013
  • A 9-month-old female Korean short hair cat weighing 2.2 kg presented for evaluation of a two-week history of obstipation. The owner reported that the cat sustained pelvic fractures 4 months previous to the onset of fecal tenesmus. On physical examination, fecal tenesmus was observed and restriction of the movement of the right coxofemoral joint was evident. Rectal palpation revealed narrowing of the pelvic canal with a hard bony protuberance at the bilateral acetabulum and pubic bones. Radiographs revealed a distended colon with feces and narrowing of the pelvic canal with abnormal structure of the pelvic bone. Conservative management consisting of stool softeners and a warm water enema was instituted; however, there was no improvement in obstipation. Partial iliac, ischial, pubic, and acetabular ostectomies were performed. Postoperative radiographs and rectal palpation revealed the enlarged pelvic canal. Stool softeners (5 ml orally twice daily) was administered following surgery for 14 days and then tapered down to 2.5 ml for 14 days. A warm water enema was performed twice postoperatively. At examination 14 days postoperatively, no problems with defecation and gait were reported. There was no evidence of obstipation and lameness of the left pelvic limb 5 months postoperatively.

Modeling of flat otter boards motion in three dimensional space (평판형 전개판의 3차원 운동 모델링)

  • Choe, Moo-Youl;Lee, Chun-Woo;Lee, Gun-Ho
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.43 no.1
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    • pp.49-61
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    • 2007
  • Otter boards in the trawl are the one of essential equipments for the net mouth to be spread to the horizontal direction. Its performance should be considered in the light of the spreading force to the drag and the stability of towing in the water. Up to the present, studies of the otter boards have focused mainly on the drag and lift force, but not on the stability of otter boards movement in 3 dimensional space. In this study, the otter board is regarded as a rigid body, which has six degrees of freedom motion in three dimensional coordinate system. The forces acting on the otter boards are the underwater weight, the resistance of drag and spread forces and the tension on the warps and otter pendants. The equations of forces were derived and substituted into the governing equations of 6 degrees of freedom motion, then the second order of differential equations to the otter boards were established. For the stable numerical integration of this system, Backward Euler one of implicit methods was used. From the results of the numerical calculation, graphic simulation was carried out. The simulations were conducted for 3 types of otter boards having same area with different aspect ratio(${\lambda}=0.5,\;1.0,\;1.5$). The tested gear was mid-water trawl and the towing speed was 4k't. The length of warp was 350m and all conditions were same to each otter board. The results of this study are like this; First, the otter boards of ${\lambda}=1.0$ showed the longest spread distance, and the ${\lambda}=0.5$ showed the shorted spread distance. Second, the otter boards of ${\lambda}=1.0$ and 1.5 showed the upright at the towing speed of 4k't, but the one of ${\lambda}=0.5$ heeled outside. Third, the yawing angles of three otter boards were similar after 100 seconds with the small oscillation. Fourth, it was revealed that the net height and width are affected by the characteristics of otter boards such as the lift coefficient.

A Study on the Fine Dust Removal Equipment of Pressurized Water type for the Removal of Exhaust Gas Fine Dust and Volatile Organic Compounds from the Non-industrial combustion plant (비산업 연소 사업장 배출 가스상 미세먼지와 휘발성 유기 화합물 제거를 위한 가압수식 미세먼지 제거 장치 연구)

  • Youn, Jae-Seo;Kim, Sang-Min;Lee, Ye-Ji;Noh, Seong-Yeo
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.11
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    • pp.506-512
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    • 2018
  • The fine dust generated in the home and restaurant business occupies a low ratio of about 4% of the total fine dust emissions. However, at the foodservice business, the rate of change of the pollutant concentration is very high, so that the temporary fine dust concentration can be measured up to 60 times. The pollutants generated from non-industrial combustion plants consist of particulate fine dust and gaseous organic compounds. To remove these pollutants, cleaning dust collection system, which is an effective system for simultaneous removal of gaseous and particulate matter, is applied. This is a method of increasing the probability of diffusion capture of the Brownian motion by pressurized liquid injection method using the atomizing nozzle. The dust removal efficiency of the fine dust collecting system was analyzed by nozzle spraying air pressure condition and angle using the manufactured fine dust removing system. As a result, it was confirmed that the efficiency of removal of fine dust and gaseous organic compounds was more than 90%. The developed system is expected to be highly usable in the future because it can remove particulate dust from the existing plant hood system without any installation cost.

Study on the Wintering of Aegypius monachus, No. 243-1 Natural Monument Bird (천연기념물 제 243-1호 독수리(Aegypius monachus)의 월동실태에 관한 연구)

  • Jin, Seon Deok;Yu, Jae Pyoung;Paik, In Hwan;Han, Sung Woo;Kim, Seong Man;Han, Kab Soo;Kang, Tae Han;Kim, In Kyu;Yoo, Seung Hwa;Lee, Ki Sup;Kim, Soo Ho;Kim, Tae Jwa;Kim, Sung Hyun;Choi, Jong Soo;Hong, Kil Pyo;Cho, Hae Jin;Ping, Ki Chang;Kang, Jung Hoon;Park, Chi Young;Kim, Woo Yeol;Oh, Hong Shik;Paek, Woon Kee
    • Korean Journal of Heritage: History & Science
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    • v.42 no.1
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    • pp.62-70
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    • 2009
  • The study was conducted from Jan. 11 to Jan. 12 2008 on 17 areas which were the wintering area of Aegypius monachus and where the birds were observed. In the study, a total of 1,912 individuals were observed to winter in the areas, which was larger than any previous observation. The study found that 1,500 individuals wintered in the central region of Korea including Gyeonggido and Kangwondo, which accounted for 78.45%, and 412 individuals (21.55%) in the southern region such as Gyeongbuk, Gyeongnam, Jeannam and Jejudo (Island). Given the number of individuals wintering by region, Jangdan Peninsula (777 individuals), Cheorwon (488 individuals) and Sancheonggun(193 individuals) were mostly found. In comparison with the previous studies, 20-30% of the individuals have moved south since 2006. This movement might be attributed to the suspension of feeding campaigns, but the birds still crowded some specific areas.

Two Fold Aspects of Mind and the Rise of Cultivation in Xunzi's Thought, treated mainly through Xiūshēnpiān, Jiěbìpiān and Zhèngmíng of his Writings (순자에 보이는 마음의 중층적 양상과 수양 문제의 대두 ­- 「수신편」, 「해폐편」 그리고 「정명편」을 중심으로 ­-)

  • Rhee, Myung-Su
    • (The)Study of the Eastern Classic
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    • no.73
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    • pp.281-302
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    • 2018
  • The role of mind is very important in Xunzi's thought. The way is permanent rule of politics that is under the control of mind which is recognizing organ for both thinking and acknowledging things in his thought. Nevertheless the mind in Xunzi's thought has desire as an organ of body to be controlled. On the other hand, the mind has conflicting two fold aspects in the course of its recognition of things like storage and vacancy, movement and calmness, and two kinds of recognizing opinion against one object. And there are various evils in thinking system of mind. In a sense, the mind of human is to be cleaned and cultivated. Xunzi proposed managing energy and cultivating mind as a thinking system. Mengzi proposed to enliven vast-flowing energy and to cultivate mind through shortening desire, while Xunzi did managing energy and caring about mind for controlling other body systems and publicly recognizing things. In Xunzi's idea the mind in the recognition of things is similar to the water in bowl as a mirror for looking at any things, and thus it is imperative for us to sink grounds in mind for becoming good water mirror. In this need the grounds of human mind would be to be sunk and also the cultivation of it would be to be demanded. Ultimately there should need the recognition of mind that is cleaned and cultivated for brightly discovering the great principle and recovering the unchangeable way with a view to preparing the condition for national peace. This thesis, in this context, to approach the meaning of mind, its two fold aspects, and the necessity of it.