• Title/Summary/Keyword: a pond

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A Development of Simplified Method for the Detention Pond Design with Runoff Reduction (유출저감용 저류지 설계를 위한 간이기법 개발)

  • Lee, Jae-Joon;Kwak, Chang-Jae;Kim, Ho-Nyun;Lee, Sang-Won
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.632-635
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    • 2007
  • Detention pond has an important role in peak flow reduction to mitigate flood damage. Design of detention pond is accomplished through the preliminary stage, planning stage, and design stage in general. New development projects produce increased peak flow and flow amounts. In this case it is necessary to design the detention pond easily and simply. The simple procedure of detention pond design is proposed in this study. The relevant variables are peak flow ratio ($\alpha$) for the before and after development, and storage ratio which is ratio of storage volume to flow amounts. Simplified method for the detention pond design with runoff reduction is easily used for practical purposes.

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Effect of Probiotics on Water Quality in the Shrimp (Fenneropenaeus chinensis) Ponds (대하 (Fenneropenaeus chinensis) 양식장 사육수에 미치는 Probiotics의 효과)

  • LIM Hyun Jeong;PARK Joong Hyun;JANG In Kwon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.37 no.2
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    • pp.91-97
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    • 2004
  • Applications of probiotics to shrimp ponds were carried out to determine their effects on water quality. Fermented solutions consisting of Bacillus spp. and Nitrosomonas spp. were applied to a 4 ha shrimp (Fenneropenaeus chinensis) pond from July to September, 2000. In the pond treated with probiotics, daily variations of DO and pH, and concentrations of DIN and DIP were lower than those in the ponds without probiotic treatment. Concentration of phytoplankton was less variable and the number of species was more variable in the probiotic-treated pond than those in the control pond. Variation of bacterial numbers and the number of Vibrio spp. were lower in the treated pond than those in the control pond. It is confirmed that the probiotics can be used to improve water quality of the shrimp ponds.

Product Development and Market Testing of Ready-to-Eat Mandu with Pond-Snail as a Health Food (건강기능성 우렁이 만두제품의 마켓 테스트)

  • Chang, Hye-Ja;Hwang, Yoon-Kyung
    • Korean Journal of Community Nutrition
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    • v.11 no.5
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    • pp.650-660
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    • 2006
  • Recently, according to increase in production of pond snails resulting from the widespread organic farming, organic farmers are showing a lot of interests in the promotion of consumption and extending the market of pond snails. This study was performed to suggest the process of product development of the ready-to-eat pond-snail Mandu as a health food, to show the results of market test of the pilot product, and to investigate the change of the sensory characteristics during storage periods. For the market test of pond-snail Mandu, the survey was developed and delivered to consumers. The questionnaire consisted of 3 parts such as respondents demographic characteristics, customer's perception of pond-snail Mandu before tasting, and customer's perception of that after tasting. And the market test was carried out with university students, welfare institution residents and apartment residents in the Seoul and Gyeonggi areas. As a result of the test, the most important purchasing factors were determined in the order of taste (49.5%), hygienic quality (12.5%), nutritional value (10%) and price (9%). And only 4.2% of respondents selected brand name as an important purchasing factor. After tasting pond-snail Mandu, consumers had suggested the better taste (t=6.986, p<0.000) and price (t=2.082, p<0.05) than those of before tasting. In response to favorable impression of pond-snail Mandu, 54.5% of total respondents evaluated positively. The favorable impressions came from iron-rich Mandu (27.6%), high protein and nutritious Mandu (24.4%), calcium-rich Mandu (17.9%), diet Mandu (13.3%), and delicious Mandu (12.5%) respectively. Sensory characteristics of pond-snail Mandu were evaluated by professional panels in terms of the softness of Mandu skin, chewiness, moistness, toothpacking, color, aroma, saltiness, and degree of plain, taste, and aftertaste. The evaluation of sensory characteristics on a 7-point scale, showed that softness of mandu skin (4.44) and aftertaste (4.11) got a low scores. The statistical difference of the tastes (p>0.05) was not founded by storage period of 7, 14, 21 and 28 days. Based on the result, the improvement of these characteristics are desired in developing the pond-snail Mandu. Research method applied to this study can be useful for developing a new product.

Feasibility Study of Natural Systems for Sewage Treatment and Agricultural Reuse (자연정화방법에 의한 오수처리와 농업적 재이용 타당성 검토)

  • 윤춘경;정광욱;함종화;전지홍
    • Magazine of the Korean Society of Agricultural Engineers
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    • v.45 no.6
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    • pp.194-206
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    • 2003
  • A pilot study was performed to examine the feasibility of the pond system for further polishing of treatment wetland effluent to agricultural reuse of reclaimed water. The constructed wetland and pond system was installed in Konkuk University and the effluent from septic tank of school building was used as an influent to the wetland system. The effluent of the wetland was used as an influent to pond systems. The influent concentrations of total coliform(TC), fecal coliform (FC), and E. coli were about $10^5$MPN/100 ml, and they were reduced to less than 10,000 MPN/100 ml on average after wetland treatments, showing over 95 % removal. And they were further reduced to less than 1,000 MPN/100 ml in average, showing over 85∼93 % removal after pond treatment. Turbidity and SS were improved effectively on average and their pond effluent concentration was about 4.5 NTU and 9.8 mg/L in average, respectively Average $BOD^5$ concentrations were also reduced substantially to 9.3 mg/L with about 83 % removal rate after wetland and pond treatment systems. Nutrients removal was relatively low and removal rate for T-N and T-P was less than 43 and 44%, respectively after wetland and pond treatment. Considering stable performance and effective removal of bacterial indicators as well as other water quality parameters, low maintenance, and cost-effectiveness, pond system was thought to be an effective and feasible alternative for agricultural reuse of reclaimed water. This paper describes a preliminary result Iron pilot study and further investigations are recommended on the optimum design parameters before full scale application.

The Application Plans of Slag to Prevent Non-point Source Pollutants Flowing into the Retention Pond (비점오염원의 유수지 유입 방지를 위한 슬래그 활용 방안)

  • Park, Jung-Hwan;Kim, Jin-Han;Jung, Jong-Tai;Jun, Se-Jin;Park, Han-Bong
    • Journal of Wetlands Research
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    • v.12 no.2
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    • pp.67-73
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    • 2010
  • This study was performed to figure out what would be effective to maintain good water quality in the retention pond which was badly polluted before. In order to keep the good water quality of the retention pond it is necessary to prevent outer non-point source pollutants from flowing into the pond. In this study, we proposed to use porous slag as a blockage of the inflow into the pond from external non-point sources. We experimented with porous slag nets to see how the water is effected. With the results of the experiments, we found out there is a close correlation($r^2=0.9765$) between contact time and the removal rate of phosphorus, therefore we can conclude that contact time affects removal rate greatly. Synthetic wastewater, activated sludge effluent, and sewage were passed through a porous slag packed bed, both phosphorus and the suspended solid in water were removed highly. With the results of these tests, we proposed to set up a porous slag packed bed inside of the retention pond and revetment to prevent external non-point source pollutants flowing into the retention pond.

A Study on Chinese Ancient Garden -focus on Qin, Han, Sui, Tang Dynasties- (중국 고대 원림에 관한 연구: 진, 선한, 수, 당대를 중심으로)

  • 박경자;양병이
    • Journal of the Korean Institute of Landscape Architecture
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    • v.27 no.2
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    • pp.119-129
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    • 1999
  • It may be said that ancient wild Chinese garden had been founded during Qin dynasty and completed through Han, Sui and Tang dynasties. At first used as hunting areas for kings, the ancient resort forests began to take forms of garden. They dug a pond in the garden and made a simulated mountains with the soil that came from the excavations for the pond and suc pavilions has Gyong, Ru, Gak etc. were built around the pond. The ponds were different in size from those in Korea, being of the lake-like size. they made three island in the pond, which were the islands of Taoist hermits with supernatural powers, called Bong-lae, Young-ju and Band-jang respectively. the traditional of making those islands began in the Qin era and were completed in the Han era, being descended to posterity as a traditional garden structure of 'three islands in one pond' garden style. Such style was brought to Korea and first appeared as Kung-Nam-Ji in Back-jae kingdom and then brought to Japan, becoming the tradition of constructing ponds from early Heian era. Those lake-like huge Chinese ponds constituted the core of ancient garden where various feasts took place. Such ponds were also placed at the center of the gardens and played the roles of feasting garden ponds. Through the above-mentioned studies of the ancient Chines garden, the origin of them and the influence of the ancient Chinese ponded garden upon those of Korea and Japan were investigated.

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ESTIMATION OF LONG-TERM POLLUTANT REMOVAL EFFICIENCIES OF WET RETENTION/DETENTION BASINS USING THE WEANES MODEL

  • Youn, Chi-Hyueon;Pandit, Ashok;Cho, Han-Bum
    • Proceedings of the Korea Water Resources Association Conference
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    • 2005.05b
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    • pp.215-219
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    • 2005
  • A macro spreadsheet model, WEANES (Wet Pond Annual Efficiency Simulation Model), has been developed to predict the long-term or annual removal efficiencies of wet retention/detention basins. The model uses historical, site-specific, multi-year, rainfall data, usually available from a nearby National Oceanic and Atmospheric Administration (NOAA) climatological station to estimate basin efficiencies which are calculated based on annual mass loads. Other required input parameters are: 1) watershed parameters; drainage area, pervious curve number, directly connected impervious area, and ti me of concentration, 2) pond parameters; control and overflow elevations, pond side slopes, surface areas at control elevation and pond bottom; 3) outlet structure parameters; 4) pollutant event mean concentrations; and 5) pond loss rate which is defined as the net loss due to evaporation, infiltration and water reuse. The model offers default options for parameters such as pollutant event mean concentrations and pond loss rate. The model can serve as a design, planning, and permitting tool for consulting engineers, planners and government regulators.

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Behavior of GGBS concrete with pond ash as a partial replacement for sand

  • Maheswaran, J.;Chellapandian, M.;Kumar, V.
    • Advances in concrete construction
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    • v.13 no.3
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    • pp.233-242
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    • 2022
  • An attempt is made to develop an eco-friendly concrete with ground granulated blast furnace slag (GGBS) and pond ash as partial replacement materials for cement and fine aggregate, respectively without compromising the strength and durability. Sixteen concrete mixes were developed by replacing cement and fine aggregate by GGBS and pond ash, respectively in stages of 10%. The maximum replacement levels of cement and fine aggregates were 50% and 30% respectively. Experimental results revealed that the optimum percentage of GGBS and pond ash replacement levels were 30% and 20% respectively. The optimized mix was used further to study the flexural behavior and durability properties. Reinforced Concrete (RC) beams were cast and tested under a four-point bending configuration. Also, the specimens prepared from the optimized mix were subjected to alternate wet and dry cycles of acid (3.5% HCl and H2SO4) and sulphate (10% MgSO4) solutions. Results show that the optimized concrete mix with GGBS and pond ash had a negligible weight loss and strength reduction.

A Comparative Study on the Ecological Pond in School between rural area and small town (농촌지역과 소도시간 학교 생태연못 특성 비교분석에 관한 연구)

  • Yoon, Yong-Gi
    • The Journal of Sustainable Design and Educational Environment Research
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    • v.11 no.1
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    • pp.11-22
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    • 2012
  • This study aims to investigate and analyze the actual conditions of the ecological ponds built in the campus sites of the elementary, middle and high schools which currently manage ecological ponds in order to find problems and directions for improvement concerning the management of the ponds as a way to build nature-friendly ecological ponds which can be used as an ecological work-study site on school campus: this study also intends to provide systematic and technological directions for the management and operation of the ecological pond. This study has selected 10 schools in North Chungcheong Province, where ponds are constructed, and investigated actual conditions of the ponds based on the survey, analysis, and evaluation standards compatible with the school environments, and finally judged the general relevancy of the ponds. The results of this study make us conclude that the most important issue to be considered in the processes of selection and investigation for school ecological pond is the location of the pond.

Influence of Pond-Snail and Duck Pasture on the Yield Components of Paddy Rice (수도작에서 왕우렁이 및 오리 방사가 수량구성요소에 미치는 영향)

  • 정순재;정원복;정대수;최봉출;오주성
    • Korean Journal of Organic Agriculture
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    • v.8 no.2
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    • pp.79-87
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    • 2000
  • This experiments was carried out to find the effect of different organic farming types, the Duck-pasture plot, the Pond-snail pasture plot andd control of the conventionalculture plot farming on the yield and its components of paddy rice. The results obtained are summarized as follows. Plant height an Tillering were significantly increase in the Duck-pasture plot. Panicle number pr hill, NO. of grain per spike and 1,000grain weight were significantly increase in the conventional culture plot. Yield pre 10a were 574.13kg at pond-snail pasture plot, 576.81kg at Duck-pasture plot and 579.04kg at conventional culture plot. From these results, it seems that the organic farming are useful and pasture of the Duck, Pond-snail for depression of the weed occurrence or increase of yield per 10a is effective as the environmental perservation farming.

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