• Journal of Korean Neurosurgical Society
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• v.52 no.2
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• pp.133-137
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• 2012

Objective : Twist-drill craniostomy (TDC) with closed-system drainage and burr-hole drainage (BHD) with a closed system are effective treatment options for chronic subdural hematoma (CSDH). The aim of this study was to analyze clinical data and surgical results from symptomatic CSDH patients who underwent TDC with closed-system drainage at the pre-coronal point (PCP). Methods : We analyzed data for 134 symptomatic CSDH patients who underwent TDC at the PCP with closed-system drainage. We defined the PCP for TDC to be 1 cm anterior to the coronal suture at the level of superior temporal line. TDC at the PCP with closed-system drainage was selected in patients with CSDH that extended beyond the coronal suture, confirmed by preoperative CT scans. Medical records, radiological findings, and clinical performance were reviewed retrospectively. Results : Of the 134 CSDH patients, 114 (85.1%) showed improved clinical performance and imaging findings after surgery. Catheter failures were seen in two cases (1.4%); the catheters were inserted in the epidural space. Recurrent cases were seen in eight patients (5.6%), and they were improved with a second BHD with a closed-system operation. Conclusion : TDC at the PCP with closed-system drainage is safe and effective for patients with symptomatic CSDH whose hematomas extend beyond the coronal suture.

• Korean Journal of Heritage: History & Science
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• v.51 no.3
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• pp.72-87
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• 2018

This study highlights a drainage gate and a ditch, which existed around the whole area of the western shore of Wolji Pond(月池) and focuses on a possible connection between the drainage facility on the western shore and the historical drainage system of Wolji Pond. Specifically, it primarily considered locations and the form of a drainage gate, the relationship between northwestern ditch of Wolji Pond and the drainage gate, and the establishment period and the character of the drainage facility on the western shore. The drainage gate found in excavation in 1975 is determined as the same facility as Surakgu(水落口) recorded on an actual measurement drawing, 1922. Therefore, it is highly probable that there were already the drainage facility in the western shore of Wolji Pond before the 1920s. The drainage gate constructed by processing rectangular stones has four drainage holes for controlling water level. The way of the drainage through the drainage holes is the same as that of the northern shore of Wolji Pond. From a cadastral map drawn in 1913, it is found that the ditch existed in northwest of Wolji Pond. The ditch was proximate to the drainage gate and shared the same axes. Hence, the ditch and the drainage gate are determined as a organic facility connected to the drainage system of Wolji Pond. In particular, the ditch existed in northwest of Wolji Pond is the basis for judging that the drainage facility in the western shore were established before the 1910s. Water flowed in through drainage holes of the drainage gate is drained into the northwest of Wolji Pond, through the ditch. The establishment period and the intention of the drainage facility on the western shore can be interpreted in two aspects. First, they might be 'a agricultural irrigation facility in the Joseon era', given that Wolji Pond was recorded as a agricultural reservoir, and that the whole northwestern area of Wolji Pond was used as farm land areas. Second, they might be 'a drainage facility for controlling the water level in creating Wolji Pond', given that the drainage gate was annexed to the lower shore forming the waterline of Wolji Pond, and that the hight of drainage holes on top of the drainage gate was similar to the full water level of Wolji Pond. Considering the related grounds and circumstance, the latter possibility is high.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.4B
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• pp.379-387
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• 2006

An urban inundation model coupling an one-dimensional stormwater model, SWMM(Storm Water Management Model), and a two-dimensional inundation model was developed to simulate inundation caused by the surcharge of storm sewers in urban areas. The limitation of this model which can not simulate the interaction between drainage systems and surcharged flow was resolved by developing Dual-Drainage inundation analysis model which was based upon hydraulic flow routing procedures for surface flow and pipe flow. The Dual-Drainage inundation analysis model can simulate the effect of complex storm drainage system. The developed model was applied to Dorim, catchment. The computed inundated depth and area have good agreement with the observed data during the flood events. The developed model can help the decision support system of flood control authority for redesigning and constructing flood prevention structures and making the potential inundation zone, and establishing flood-mitigation measures.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2682-2687
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• 2008

Depressurized drainage systems have been used for more than 30 years and are becoming a common part of urban drainage infrastructures. The hydraulic principles governing the operation of the depressurized drainage systems were studied in this paper and particularly, focused on the analysis of unsteady characteristics of the two-phase flow. A definition of the filling ratio was outlined and types of flow pattern were classified according to the filling ratio. Experiments were conducted to investigate the main features of pressure fluctuation. All results were found to depend on the filling ratio of the upstream pipe flow as well as the upstream Froude number.

• Proceedings of the KSR Conference
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• 2008.11b
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• pp.935-940
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• 2008

To maintain the primary stage of design, it is not too much to say that drainage systems should has been to maintain the most factor in earthwork structures. The durability of earthwork structures has about over 90 years as like concrete structures and has easily used to construction materials. Even if is a good earthwork materials, it hasn't lose design life at inadequate drainage system. In case of railway was frequently performed a maintenance works after construction 5 years because embankment site hasn't installed a concrete duck. In this study, the drainage standard of railway reviews the technological levels of drainage system by comparing the code for design of railway and road.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.4 no.3
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• pp.55-65
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• 2001

The hydrological cycle system in the city is generally characterized by quick runoff, bad infiltration, low evaporation rate, and so on. It is caused by sealing greens up with pavements. Also, there are lots of contradictory environmental problems, such as inundation, the lack of underground water and dryness in the city, caused by the urban drainage system which is mostly focused on the quick draining off rainfall. In addition, the technique joining rain and sewage, which has more dangers of inundation, occupies 66% between two Korean drainage systems which consist of joining and dividing system. There has been some need to convert the present drainage system into the environmentally friendly hydrological cycle system. This is a theoretical study to examine some foreign cases and suggested applicable methods in our country, focusing on the environmentalyl friendly system of rainfall drainage. The precipitation treatment system can be made up of some possible phases choosing from premanagement, utilization, infiltration, retention, and inducement phases. Therefore, this study mostly focused on infiltration, retention, and inducement phases. It is necessary to suggest the multifunctional utilization of outdoor spaces, especially applying in new constructing and re-constructing residential estates.

• Journal of The Korean Society of Agricultural Engineers
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• v.66 no.3
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• pp.15-23
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• 2024

Subsurface drainage improves crop productivity in poorly drained soils but may also substantially contribute impairment of surface water quality due to excess leaching losses of nutrients like Nitrate-Nitrogen (NO₃-N). This research presents preliminary findings from a 3-years tile depth and spacing study in Illinois state that includes three drain spacings implemented in 2 plots. We found that the plot with the narrower subsurface drainage (Case 1) exported more drainage water compared to the plot with the narrower subsurface drainage system (Case 2). The total drainage water from Case 1 plot showed 57% more compared to Case 2 plot. Whereas we observed that the plot with narrower drain spacing (Case 1) exported only 9% more NO₃-N leaching losses compared to the wider plot (Case 2). The average corn yield was observed higher in plot Case 1 compared to Case 2. Especially, we observed about 7% higher corn yield in plot Case 1 compared to Case 2 plot in the relatively dried year (2022). The preliminary findings for this study suggest that subsurface drainage systems can be optimized to reduce nutrient losses while improving the crop productivity.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.5 s.112
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• pp.69-82
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• 2005

These studies were carried out (1) to investigate the growth characteristics of Sedum album L. in the field, (2) to propose a suitable shallow peen roof system for this plant, and (3) to evaluate plant growth in the proposed system over the long term. The growth characteristics, such as morphological properties, growth habit, shade tolerance, and flowering, were surveyed. In experimental shallow green-roof systems, the effects of drainage type, substrate type, and soil depth on plant growth were investigated. Then drought tolerance was investigated. After planting Sedum album L. in the proposed system survival rate, cover, and resistance to insects, heal and cold were evaluated for about 2 years. The results of these studies are summarized below. 1. In the field, the aboveground part of Sedum album L. did not die back during the winter. Plant height was 4$\sim$7 cm. Roots were distributed to a depth of 5$\sim$7 cm. Sedum album L. is a compact ground-cover plant that spreads vigorously. Shading condition of less than $30\%$ of full sunlight didn't cause any trouble, but shading conditions above $87\%$ made the shape of the shoots and leaves abnormal. The plant bloomed from June to August and had a rather large compound umbel of white, star-shaped flowers. 2. Two systems, a drainage-blend-10 cm soil depth and a reservoir$\cdot$drainage-blend-15 cm soil depth, performed best in terms of cover, fresh weight, and dry weight. The first has an advantage for green roofs because it is lighter than the latter. 3. In drainage-blend-10 m soil depth and modified reservoir · drainage-blend-10 cm soil depth system no plants died for about 4 months after stopping the irrigation. The visual quality of the latter system was above 5 for 4 months and that of the former was under 5 after 2 months. In the field, however, the drought tolerance of Sedum album L. grown in the former would be enough to withstand the dry season. Considering the urban ecosystem and the importance of healthy growth the modified reservoir $\cdot$ drainage-blend-10 cm soil depth system was finally recommended. This system was composed of a 4 cm thick drainage layer and drain outlets placed at a height of 2.5 cm. 4. In the proposed system, the survival rate was $100\%$, and there was no injury induced by insects and heat. The leaf density decreased a little in winter. Cover increased throughout the year. Sedum album L. was planted with a cover of 72$cm^{2}$ on 3 April 2003; on 16 June 2003 and 15 June 2004, cover was $132.66\pm$5.87 $cm^{2}$(1.8 times) and $886.98\pm$63.51 $cm^{2}$(12.3 times), respectively.

• Journal of Korean Neurosurgical Society
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• v.41 no.4
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• pp.261-263
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• 2007

Subdural hygromas are easily treated by trephination and drainage. Therefore, most neurosurgeons do not consider subdural hygromas seriously. However, various complications including intracerebral hemorrhage may develop after rapid drainage of subdural hygroma although rare. Postoperative intracerebral hemorrhage presents with a rapid deterioration of consciousness and focal neurological deficits occurring immediately after drainage of the subdural hygroma. The authors present an unfortunate massive intracerebral hemorrhage and pneumocephalus following drainage of the bifrontal subdural hygroma. The patient subsequently died. To prevent this disastrous complication, close neurosurgical observation and gradual drainage under a closed system seem mandatory. Possible pathogenic mechanisms for this unfavorable complication is discussed with a review of pertinent literatures.

• Structural Engineering and Mechanics
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• v.52 no.6
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• pp.1257-1271
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• 2014

The hydraulic deterioration of the drainage system in tunnel linings is one of the main factors governing long-term lining-ground interactions during the lifetime of tunnels. Thus, in the design procedure of a tunnel below the groundwater table, the possible detrimental effects associated with the hydraulic deterioration should be addressed. Hydraulic deterioration in double-lined tunnels can occur because of reasons such as clogging of the drainage layer and drain-pipe blockings. In this study, the coupled mechanical and hydraulic interactions between linings due to drain-pipe blockings are investigated using the finite-element method. A double-lined structural model incorporating hydraulic behavior is developed to represent the coupled structural and hydraulic behavior between the linings and drainage system. It is found that hydraulic deterioration hinders flow into the tunnel, causing asymmetric development of pore-water pressure and consequent detrimental effects to the secondary lining.