• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.565-571
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• 2010

One of the disadvantages of flooding treatment for desalting from soils is that salts move to deep soils after flooding and at the end reaccumulate at the soil surface through capillary movements. This study was carried out to remove salts from soils in plastic film houses by a modified flooding method, drainage after flooding. The method successfully removed salts at the soil surface and salts did not move to the deep soil. Drained water containing N, P and K could be reused as fertilizer. By applying small amount of MgO, turbidity of water flooded decreased in 30 min by 95%. Struvite should be formed since the flooded water contain ammonia and phosphorous and their concentrations were decreased. This could be utilized as fertilizer which provides a slow-release source of phosphorus, magnesium and nitrogen that features low inherent water solubility.

• Journal of Korea Water Resources Association
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• v.48 no.8
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• pp.685-693
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• 2015

We propose a method for deriving the relationship between channel width and discharge from remote sensing products. Stream widths at points distributed along a river network can be measured from high-resolution remote imagery. Further, corresponding drainage area for these points can be calculated using digital elevation models, making it possible to construct width-drainage area relation. On the other hand, the relationship between the flow discharge and the drainage area is obtained from historical data measured at ground stations. By coupling these two relationships, we can finally derive the width-discharge relationship which comprises an important component of downstream hydraulic geometry. The proposed method was tested for the Nakdong River and the Seomjin River, successfully capturing power-law exponents in the width-discharge relationships reported in earlier studies. The proposed approach can serve as an alternative for obtaining the hydraulic geometry relationship under the limits of ground data.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.38 no.8
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• pp.905-910
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• 2014

The steel grating discussed in this study is a drain cover that enhances the rigidity of the steel frame using an inclined inflow tract for wastewater, facilitates smooth drainage, and prevents the escape of bad smell from the drain. Recently, the urban problem of bad smell in sewerage lines has been hindering the improvement of living standards. Moreover, the frequent failure of existing products deters bad smell prevention measures and results in administrative power and budget wastage. The pressure to reduce budgets propels the increased demand for functional steel grating. Thus, this study focused on optimizing the design parameters of a steel grating by simultaneously considering its rigidity and drainage efficiency.

• Journal of the Korean GEO-environmental Society
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• v.13 no.3
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• pp.77-83
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• 2012

The most of horizontal drainages, which is composed of the aggregates made of sand and crushed stone, are used to improve the soft ground. However, where the aggregates are used as the horizontal drainage, it often brings about the delay of consolidation. For this reason, the horizontal drain pipe system is applied to properly improve the soft ground using a drainage pipe instead of horizontal drainage. This system is direct drain method for disappearing the excess porewater pressure which is caused by placing of fill on the soft ground. The large-scale field test was conducted in order to evaluate the applicability and constructability of the horizontal drain pipe system. The settlement characteristics of improved ground with horizontal drain pipe system was observed. It is also compared to the conventional soft ground improvement method to confirm its effectiveness.

• Geotechnical Engineering
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• v.11 no.4
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• pp.125-140
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• 1995

Generally, the groundwater pressure is not considered in the design of concrete lining of bottom drainage tunnel. This design method implies that the phreatic surface is drawdown to the bottom of tullnel. When tile groundwater is continually supplied without changing of groundwater table, there is a possibility at which the groundwater pressure acting on the tunnel lining after the completion of tunnel. Therefore, the safety of tunnel lining must be checked in this case. In this paper, the stability of bottom drainage tunnel which is affected by groundwater discharge is analzed by using of the Finite Element Method at the 2 sections of subway where the groundwater level has a tittle change during the construction. As the result of analysis, the grouting for the water tightness and the permanent monitoring system of tunnel are required for maintaining of long-term stability of bottom drainage tunnel for the case of groundwater plassure acting on the tunnel lining is greater than that of design stage.

• KCID journal
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• v.6 no.1
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• pp.48-59
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• 1999

The study was carried out to review the present method of velocity measurement by the current meter in the streamflow and to suggest a practical method applicable in the field. It was found that the mean velocity of 0.7m/s was the threshold of velocity di

• Journal of Korean Society of Water and Wastewater
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• v.14 no.3
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• pp.251-259
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• 2000

In this study, the urban runoff models, ILLUDAS model and SWMM, are analyzed the probable peak discharge and discharge using rainfall distribution by Huff's method at Bum-uh chun area in Taegu city. The probability rainfall and intensity is analyzed by Pearson-III type. The rainfall duration, 90 minutes, is determined by the critical duration computed the maximun peak discharge for some rainfall durations. The peak discharge according to Huff's rainfall distribution types compute in order of type 3, type 4, type2, and type 1, so Huff's 3 type is selected as an adequate rainfall distribution in Bum-uh chun basin. ILLUDAS model and SWMM are shown as good models in Bum-uh chun, but SWMM is computed higher peak discharge than ILLUDAS model, so SWMM is shown as the adequate urban runoff model for the design of interior drainage in urban basin.

• Journal of Chest Surgery
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• v.21 no.6
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• pp.1084-1094
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• 1988

Conservative management of 3 iatrogenic perforations of intrathoracic esophagus was reviewed. The primary disorders were achalasia in 2 patients and congenital tracheoesophageal fistula in 1 patient. Perforation occurred after treatment of the primary disorders in the distal esophagus in 2 patients and mid-thoracic esophagus in 1 patient. All the perforations appeared late after the previous treatments and the inflammation spread to mediastinum and pleural cavity in all the 3 patients. Conservative management of esophageal perforation was carried out with intraluminal drainage from the perforated site of esophagus[insertion of Levin`s tube and continuous suction], pleural drainage and feeding of liquid diet through gastrostomy tube with Fowler`s position. The patients revealed spontaneous closure of perforated sites about 3 to 4 weeks after this conservative management without open thoracotomy. This result suggests that this conservative management may be accepted as therapeutic method in the thoracic esophageal perforations regardless of cause and time of the perforation.

• Journal of Chest Surgery
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• v.21 no.5
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• pp.948-953
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• 1988

A technique applicated for physiologic correction of complex congenital cardiac disease suitable for Fontan procedure in which drainage of left superior vena cava and hepatocardiac vein to left atrium combined is described. We made one systemic venous baffle from left hepatocardiac vein to left superior vena cava and another systemic venous baffle from right inferior vena cava to the right superior vena cava with rigid prosthetic material[0.5mm thickness PTFE patch]. And then we anastomosed directly between the right sided atrial appendage and right pulmonary artery, and left-sided atrial wall beneath the appendage and left pulmonary artery. We believe that this procedure is superior to the method using intraatrial tube graft to divert the left hepatocardiac venous blood to right atrium, and applicable for physiologic correction of any complex congenital cardiac disease suitable for Fontan-type procedure in which anomalies of systemic venous drainage combined.

• Magazine of the Korean Society of Agricultural Engineers
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• v.39 no.2
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• pp.134-142
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• 1997

This study was performed to evaluate the drain runoff characteristics from one paddy field, and to provide the basic data required for the determination of flood discharge and unit drainage water for drainage improvement and farmland consolidation. For this purpose, under the assumption that drain discharge from paddy field was similar to outflow of reservoir, runoff model based on storage equation was applied to the experimental field, and simulated results were compared to the measured discharge at weir point. To estimate effective storage volume of paddy field with water depth, 4 regression formula were examined such as linear, exponential, power, and combined. From the observed runoff characteristics, it was shown to be 3.3~16.3${\ell}$/sec in weir discharge, 57.2~98% in runoff ratio, and relative error of simulated result was 3.0~39.4%, 8.5 ~56.0 % for peak flow and runoff ratio, respectively. Curve number by SCS method was calculated as mean value of 96.4 using measured rainfall and runoff data, it was considered relatively high because paddy field has generally flooding depth contrary to the upland watershed area.