• Title/Summary/Keyword: dry bed

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An Analysis of Runoff Reduction Effect of Infiltration Facilities in Urban Area (도시유역에서 침투시설의 우수유출저감효과 분석)

  • Lee, Jae-Joon;Kim, Ho-Nyun;Kwak, Chang-Jae;Lee, Sang-Won
    • 한국방재학회:학술대회논문집
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    • 2007.02a
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    • pp.628-631
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    • 2007
  • One of the structural measures for the peak flow reduction is infiltration facilities. There are many types in infiltration facilities - infiltration basin, trench, bed, porous pavement, percolated subdrain, dry well. In this study runoff reduction effect of infiltration trench is analyzed by WinSLAMM. Runoff reduction effect is investigated by each design rainfall and temporal pattern of rainfall particularly. The biggest reduction is shown in Yen and Chow's temporal pattern of design rainfall and the smallest reduction is shown in Huff's first quartile pattern. Runoff reduction rate is presented about 6 to 14 percentage, and the larger return period, the smaller runoff reduction rate.

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Acupuncture clinical trial study for treatment of Nocturnal Enuresis (야뇨의 침술 치료 임상시험에 대한 최근 경향)

  • Chang, Gyu-Tae
    • The Journal of Pediatrics of Korean Medicine
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    • v.17 no.2
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    • pp.213-224
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    • 2003
  • Background and Objectives: Nocturnal enuresis is a common problem that can be troubling for children and their families. Treatment options include nonpharmacologic and pharmacologic measures. Various nonpharmacologic treatments have been shown to have a positive effect on bed-wetting in small studies but have not been extensively evaluated (generally weak strength of evidence). This study was undertaken to determine if there is any evidence for the clinical efficacy of acupuncture for treatment of nocturnal enuresis. Methods : Author conducted a computerized literature search in following database: Medline(via Pubmed), NDSL. There were no restrictions on the language of publication. The data were extracted in a standardized, predefined manner and assessed critically. Results : 4 article was selected. Acupuncture is composed of general acupuncture, electro, laser. Acupuncture treatment of the children had significantly more dry night than before treatment Conclusion : Alternative, nonpharmacological approach using acupuncture works in children with monosymptomatic nocturnal enuresis.

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Properties of Products from Slow Pyrolysis of Geodae-Uksae 1 (거대억새의 저속 열분해 생성물 특성 분석)

  • Lee, Yongwoon;Eum, Pu-Reun-Byul;Jung, Jinho;Hyun, Seunghun;Park, Yong-Kwon;Ryu, Changkook
    • 한국연소학회:학술대회논문집
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    • 2012.04a
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    • pp.235-237
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    • 2012
  • Geodae-Uksae 1 is a variety of Miscanthus sacchariflorus recently discovered in Korea. It is being mass-cultivated for use as energy crop due to its superior productivity, as high as 30 ton/ha/yr for the dry mass. This study investigates the method of producing biochar and bio-oil from the crop using slow pyrolysis. Especially, the study focused on assessing the biochar properties for its application to soil to improve soil quality and sequestrate carbon. Using an electrically heated packed bed reactor, the products of slow pyrolysis from Geodae-Uksae 1 were produced over a temperature range of $300-700^{\circ}C$ with a heating rate of $10^{\circ}C/min$. The biochar, condensable vapor (bio-oil) and residual gases were characterized for the physical and chemical properties. It was concluded that the ideal temperature for pyrolysis to produce biochar is $500^{\circ}C$.

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DEVELOPMENT OF A GRAIN CIRCULATING TYPE NATURAL AIR IN-BIN DRYER

  • Yun, H.S.;Chung, H.;Cho, Y.G.;Park, W.K.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 2000.11b
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    • pp.405-412
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    • 2000
  • A natural air in-bin grain dryer with a grain circulator was developed for on farm use. Natural air drying test for rough rice was carried out to evaluate drying rate, uniformity of moisture content distribution in grain bed and energy consumption. It took 10 days to dry 8 ton of paddy rice from 21.9%(w.b) to 16.7%(w.b) moisture contents using the prototype dryer. The average drying rate was 0.52%/day. The uniformity of moisture content after drying was superior to the conventional natural air dryer where is grains were not circulated during drying periods. The dryer performance evaluation index was 738.3KJ/(kg.water), which was more effective than that of grain circulation t)pe hot air dryer(3,500-5,000 KJ/kg.water).

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Characteristics of Coal Water Fuel by Various Drying Coals, Surfactants and Particle Size Distribution Using Low Rank Coal (건조된 저등급석탄과 첨가제 및 입자크기에 대한 석탄-물 혼합연료(CWF)의 특성)

  • Kim, Tae Joo;Kim, Sang Do;Lim, Jeong Hwan;Rhee, Young Woo;Lee, Si Hyun
    • Clean Technology
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    • v.19 no.4
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    • pp.464-468
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    • 2013
  • In this study, in order to increase solid content of coal water fuel (CWF), various experimental parameters (i.e., coal type, additive, particle size distribution, drying method) were evaluated. To investigate the drying method, specimen is compared to using flash dry, fluidized bed dry and oil deposit stabilized coal. Difference of the solid content between low rank coal and high rank coal in this case indicate that high rank coal exhibits more higher than 20% of the solid cotent. And specimen for dispersibility was prepared by using dispersing agent of 4 types. As a result, using the dispersing agent was shown 5% higher in sold content than the case of not using the dispersing agent. Efficiency of CWF was improved by using fine coal of 80% in the particle size distribution of coal. Result of CWF using drying methods of 3 types, oil deposit stabilized (ODS) coal dried and stabilized was effective 12% higher in sold content than raw coal.

Propagation Analysis of Dam Break Wave using Approximate Riemann solver (Riemann 해법을 이용한 댐 붕괴파의 전파 해석)

  • Kim, Byung Hyun;Han, Kun Yeon;Ahn, Ki Hong
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.29 no.5B
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    • pp.429-439
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    • 2009
  • When Catastrophic extreme flood occurs due to dam break, the response time for flood warning is much shorter than for natural floods. Numerical models can be powerful tools to predict behaviors in flood wave propagation and to provide the information about the flooded area, wave front arrival time and water depth and so on. But flood wave propagation due to dam break can be a process of difficult mathematical characterization since the flood wave includes discontinuous flow and dry bed propagation. Nevertheless, a lot of numerical models using finite volume method have been recently developed to simulate flood inundation due to dam break. As Finite volume methods are based on the integral form of the conservation equations, finite volume model can easily capture discontinuous flows and shock wave. In this study the numerical model using Riemann approximate solvers and finite volume method applied to the conservative form for two-dimensional shallow water equation was developed. The MUSCL scheme with surface gradient method for reconstruction of conservation variables in continuity and momentum equations is used in the predictor-corrector procedure and the scheme is second order accurate both in space and time. The developed finite volume model is applied to 2D partial dam break flows and dam break flows with triangular bump and validated by comparing numerical solution with laboratory measurements data and other researcher's data.

A Study on the Wastewater Treatment Characteristics of the Intermediately Aerated Fluidized Bed (간접포기식 유동상법에 의한 폐수처리 특성에 관한 실험적 연구)

  • Lee, Jeoung Su;Kim, Hwan Gi
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.14 no.2
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    • pp.367-378
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    • 1994
  • The wastewater treatment characteristics of the fluidized bed filled with sand media and intermediately aerated were studied experimentally, and the obtained results were as follows; 1. The formations of biofilm on the media were greatly affected by the recirculation velocities. 2. Under the experimental condition that BOD loading rate was $4.2kg-BOD_5/m^3{\cdot}d$, the optimum media concentration was $261kg/m^3$ and the optimum recirculation velocity 1.35 cm/sec. 3. For the effluent quality of 20 mg-BOD/l and 20 mg-SS/l, the maximum allowable loading rate was about $8kg-BOD_5/m^3{\cdot}d$. 4. The dry density of biofilm was about 5.6% regardless of the filled media quantities and recirculation velocities. 5. Under the experimental conditions, the effluent solids concentration was below 20 mg/l, and the elimination of final clarifier can be expected.

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Effect of Ondol on physiological Responses during Sleep (I) -On the focus of Bedclimate in Autumn and Winter- (온돌환경이 수면시의 생리반응에 미치는 영향(제1보) -가을, 겨울철 수면시 침실내 온열환경과 침상기후-)

  • Lee, Sun-Won;Gwon, Su-Ae;Choe, Jeong-Hwa
    • Journal of the Korean Society of Clothing and Textiles
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    • v.20 no.4
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    • pp.697-706
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    • 1996
  • The actual conditions of bed climate are investigated depending on the regions and housing styles used on ondol in autumn and winter. Sixty healthy men and women (30 of them live in apartmrnt and 30 of them live in detached house, 20 of them live in Wonju, 20 of them live in Wonju, 20 of them live in Cheongju and 20 of them live in Pusan) The results are as follows: 1) No significant differences was shown between the seasons of bedclothes thickness. 2) In the autumn, the temperature and humidity of bedroom, on the mattress, inside the bedquilt, and inside the sleep-wear were higher than those in the winter. The temperature of ondol floor and under the mattress in winter were higher than those in the autumn. 3) The differences of the temperature and humidity of bedroom, the bed climate, and the clothing microclimate were significant by the regions and housing styles in both seasons. In both seasons, the temperature of bedroom, on the mattress, inside sleep-wear in the apartment were higher than those in the detached house. 4) The differences of subjective sensation on the bedroom conditions were not significant by the sextons, the regions, and the housing styles. Most subjects perceived that the conditions of bedroom were somehow hot and dry, but comfortable.

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Derivation Method of Rating Curve and Relationships for Flow Discharge-Total Sediment at Small-Midium Streams in Agrarian Basin (농경유역 중소하천에서 유량과 총유사량의 관계식 유도방법)

  • Lee, Jong-Seok;Kim, Chi-Gon;You, Eui-Geen
    • The Journal of the Korea Contents Association
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    • v.15 no.8
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    • pp.544-555
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    • 2015
  • This study aims to derivate of the relationship and rating curve for the flow discharge-total sediment using the measured field data from the main points of small-medium stream reaches in agrarian basin. The total sediment of measured data are obtained by bed load added to suspended load which analyzed using the particle size distribution curve of sieve test and the dry or the filtration method from the collected samples by samplers (DH-48, D-74 and BLH-84, BL-84) at the stream bed and the depth-averaged concentration, respectively. These field data had been collected from August 2012 to September 2014 at the seven measuring stations of the national-local channel reaches of the four study streams in the Nonsan river systems of agrarian basin. As a result, the relationships and the rating curve for the flow discharge-total sediment are derived as a function pattern of power law by analyzing on a distribution characteristic of the database set and it will be used as a useful tool to analyze erosion, deposition, and transportation in theoretical research as well as in practical application of the hydraulic sedimentation engineering.