• Title/Summary/Keyword: drainage method

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Partial Drainage Characteristics of Clayey Silt with Low Plasticity from the West Coast (서해안 저소성 점토질 실트 지반의 부분배수 특성)

  • Kim, Seok-Jo;Lee, Sang-Duk;Kim, Ju-Hyun
    • Journal of the Korean Geotechnical Society
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    • v.32 no.9
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    • pp.17-27
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    • 2016
  • Parial drainage characteristics of clayey silt with low plasticity from the west coast (Incheon and Hwaseong) was analyzed using CPTU based existing correlation equations and compulsory replacement method. Generally, the estimated $OCRs={\kappa}{\cdot}((q_t-{\sigma}_{vo})/{\sigma}^{\prime}_{vo})$ using Powell and Quartman(1988) were higher than those obtained by the oeodometer tests. These trends were noticeable for the layers containing a lot of silty and sand soils. The assessment of partial drainage conditions was performed through Schnaid et al. (2004)'s equation; it is based on plotting the normalized cone resistance, $Q_t$ versus the pore pressure parameter, $B_q$ in combination with the strength incremental ratio, $s_u/{\sigma}^{\prime}_{vo}$ to the CPTU data. It is evident that more than half of the data fall in the range where $B_q$ < 0.3, corresponding to the domain in which the partial drainage prevails when testing normally consolidated soils at a standard rate of penetration (2 cm/s). To estimate the replacement depth of clayey silt with low plasticity, back analysis was carried out to evaluate the internal friction angle based on where the design depths are equal to the checked depths using bearing capacity equation. The internal friction angels obtained from the back analysis tended to increase as the plasticity index decreases, which is ranged approximately from ${\varphi}^{\prime}=2^{\circ}$ to ${\varphi}^{\prime}=7^{\circ}$.

Effect of Water Management on Greenhouse Gas Emissions from Rice Paddies Using a Slow-release Fertilizer (완효성 비료를 시용한 논에서의 물관리에 따른 온실가스 배출량 평가)

  • Eun-Bin Jang;Hyun-Chul Jeong;Hyo-Suk Gwon;Hyoung-Seok Lee;Hye-Ran Park;Jong-Mun Lee;Taek-Keun Oh;Sun-Il Lee
    • Korean Journal of Environmental Agriculture
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    • v.42 no.2
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    • pp.112-120
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    • 2023
  • Methane (CH4) and nitrous oxide (N2O) are significant contributors to greenhouse gas (GHG) emissions from rice fields. Mid-summer drainage is a commonly practiced water management technique that reduces CH4 emissions from rice fields. Slow-release fertilizers gradually release nutrients over an extended period and have been shown to reduce N2O emissions. However, the combined effect of slow-release fertilizer and water management on GHG emissions remains unclear. This study compared GHG emissions from a rice paddy subjected to mid-summer drainage for 10 days (control) with that of a rice paddy subjected to prolonged mid-summer drainage for 20 days combined with slow-release fertilizer (W+S). Gas sampling was conducted weekly using a closed chamber method. During the rice cultivation period, cumulative CH4 and N2O emissions were reduced by 12.3% and 16.2%, respectively, in the W+S treatment compared to the control. Moreover, the W+S treatment exhibited a 1.9% increase in grain yield compared to the control. Under experimental conditions, slow-release fertilizers, in combination with prolonged mid-summer drainage, proved to be the optimal approach for achieving high crop yield while reducing GHG emissions. This represents an effective strategy to mitigate GHG emissions from rice paddy fields.

Transcholecystic Duodenal Drainage as an Alternative Decompression Method for Afferent Loop Syndrome: Two Case Reports (들장관증후군의 대체 감압 치료로서 경담낭 십이지장 배액술: 두 건의 증례 보고)

  • Jihoon Hong;Gab Chul Kim;Jung Guen Cha;Jongmin Park;Byunggeon Park;Seo Young Park;Sang Un Kim
    • Journal of the Korean Society of Radiology
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    • v.85 no.3
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    • pp.661-667
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    • 2024
  • Afferent loop syndrome (ALS) is a rare complication of gastrectomies and gastrointestinal reconstruction. This can predispose patients to fatal conditions, such as cholangitis, pancreatitis, and duodenal perforation with peritonitis. Therefore, emergency decompression is necessary to prevent these complications. Herein, we report two cases in which transcholecystic duodenal drainage, an alternative decompression treatment, was performed in ALS patients without bile duct dilatation. Two patients who underwent distal gastrectomy with Billroth II anastomosis sought consultation in an emergency department for epigastric pain and vomiting. On CT, ALS with acute pancreatitis was diagnosed. However, biliary access could not be achieved because of the absence of bile duct dilatation. To overcome this problem, a duodenal drainage catheter was placed to decompress the afferent loop after traversing the cystic duct via a transcholecystic approach. The patients were discharged without additional surgical treatment 2 weeks and 1 month after drainage.

The Experimental Study on Mass Nail Reinforcing Effects with Variation of Water Content (함수비 변화에 따른 Mass Nail 공법의 사면 보강 효과에 관한 실험적 연구)

  • Kwon, Kyoung-Jun;Kim, Won-Il;Hong, Chang-Sun;Ahn, Won-Sik
    • Journal of the Korean Society of Hazard Mitigation
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    • v.10 no.5
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    • pp.109-116
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    • 2010
  • Infiltration and the rising level of groundwater caused by rainfall are a major cause of the landslide and sliding. In order to secure the safety factor of slope, the slope stabilization and reinforcement works are used to enhance consistency. Nailing, Slope Drainage method and the surface vegetation measures can be simultaneously applied in the Mass Nail method, which is also environmental friendly reinforcement method. To demonstrate the reinforcement effect of a strengthened slope by Mass Nail, the changes in water contents by rainfall were considered while performing Scale Model Test. As a result, safety factor of reinforced slope was about 1.4~2.3 times increased on the unstrength slope. In the case of increasing water content 10% to 22%, The maximum stress was reduced to 12%~24% at the average rate of 18% on the unstrength slope and the reinforced slope by the Mass Nail Method was reduced to 4%~23% at the average rate of 14%.

A Study on the River Discharge Measurement Techniques (하천유량 측정기법에 관한 연구)

  • 김성원;지홍기
    • Journal of Environmental Science International
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    • v.7 no.6
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    • pp.793-801
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    • 1998
  • In this study, the Dilution Method is used to measure river discharge through the hydraulic model test. the dilution method is divided into Constant-Rate-Infection Method and Slug-Injection Method in the river discharge measurement techniques. When the dilution method is applied in the hydraulic model flume, it is analyzed that the estimated error of constant-rate-injection method is less than that of the slug-in-jection method, and the result shows that floodflow analysis is more efficient than lowflow analysis as compared observed discharge with calculated discharge. The result of statistical error analysis shows that the constant-rate-injection method is appropriate technique for the measurement of the river discharge. Therefore, the dilution method among the river discharge measurement techniques can be applied for the river basin which can't be measured with current meter or unsteady-flow regime in the urban-small drainage or hydraulic structure equipment area and can be obtained more exact results than any other discharge measurement techniques.

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Surgical Treatment of Loculated Empyema - Closed Rib Resectional Drainage (국소화 농흉의 외과적 치료 - 폐쇄식 늑골절제 배농술 -)

  • 허진필;이정철;정태은;이동협;한승세;선기남
    • Journal of Chest Surgery
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    • v.31 no.11
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    • pp.1063-1069
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    • 1998
  • Background: Multi-loculated empyema makes treatment difficult, and more so when thoracentesis or chest tube drainage fails. Materials and methods: From December 1991 to December 1997, we performed closed rib resectional drainage for 18 cases of loculated empyema on the fibrinopurulent or early chronic phase. Results: Surgery was performed on patients with loculated empyema complaining of persistent symptoms due to failure of treatment by thoracentesis(8 cases) or chest tube drainage(10 cases). Predisposing factors of empyema were pneumonia in 13 cases, clotted hemothorax in 3 cases, cholecystectomy, and tuberculous pleurisy in 1 case. Causal organisms were cultured in 8 cases(42.1%), and methicillin-resistant staphylococcus aureus was found in 3 cases, pseudomonas aeruginosa in 2 cases, and enterococcus aerogens, α-hemolytic streptococcus, and acinetobacter baumannii were found in 1 case. Size of loculations was various, and computed chest tomogram showed multiple loculations of empyema numbering 1∼4(mean 1.78±1.00). Operating time was relatively short, about 55∼140 mins(mean 102.8±30.8). All toxic symptoms including fever disappeared postopratively and general conditions improved very quickly in all patients. Length of chest tube indwelling time and hospital stay after surgery were 3∼42 days(mean 11.4±11.5) and 6∼36 days(mean 12.9±8.1), respectively. Complications of prolonged drainage occurred in 2 cases and no death occurred. There were no recurrences and chest x-rays taken 3∼6 months after surgery showed normal findings in 14 cases and slight pleural thickening in 4 cases. Conclusions: Closed rib resectional drainage requires very simple techniques and has excellent outcomes and little complications, therefore, we think that it is the choice of operation for patients with loculated empyema on the fibrinopurulent or early chronic phase.

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Effects of the Drainage Methods on Antioxidant Compounds and Antioxidant Activity of Ethanolic Extracts on Adzuki Bean (논 재배 배수방법이 팥 에탄올 추출물의 항산화성분 및 항산화활성에 미치는 영향)

  • Woo, Koan Sik;Jung, Ki Yuol;Song, Seuk Bo;Ko, Jee Yeon;Lee, Jae Saeng;Choi, Young Dae;Yun, Eul Soo;Jung, Tae Wook;Oh, In Seok
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.59 no.3
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    • pp.350-358
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    • 2014
  • This study investigated the changes of antioxidant compounds and antioxidant activity of adzuki bean by drainage methods in poorly drained sloping paddy field. The soil moisture contents of under pipe and open ditch drainage on very poorly drained paddy soil were $18.52{\pm}4.58$ and $19.01{\pm}4.25%$, and imperfectly drained paddy soil were $14.87{\pm}4.82$ and $18.64{\pm}3.85%$, respectively. Moisture, protein, fat and ash contents of adzuki bean with drainage methods were 10.10~11.60, 14.13~21.75, 0.02~0.73 and 2.81~3.45 g/100 g, respectively. The total polyphenol, flavonoid and tannin contents, and radical scavenging activity of adzuki bean showed significant differences by drainage methods. The total polyphenol, flavonoid, and tannin contents by drainage methods were 2.73~4.14 mg GAE/g, 1.07~1.43 mg CE/g, and 1.27~1.84 mg TAE/g, respectively. The DPPH and ABTS radical scavenging activities were 2.84~4.47 and 5.11~6.74 mg TE/g, respectively. The antioxidant compounds and radical scavenging activity of the adzuki bean by drainage methods were frequently affected soil water.

The Method for Transforming the Shape File in ESRI into the Oracle Spatial DB for the Spatial DB Construction of the Drainage System (하수관거 공간DB 구축을 위한 ESRI 공간 파일의 오라클 공간DB 자동 변환 기법)

  • Kim, Ki-Uk;Hwang, Hyun-Suk;Kim, Chang-Soo
    • Journal of Korea Multimedia Society
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    • v.12 no.7
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    • pp.989-996
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    • 2009
  • Recently, use of the GIS (Geographic Information System) for the disaster of the urban inundation is increasing. The digital disaster map is the system which analyzes the occurrence area of inundation in the past and forecasts the flood areas by the hydrology method. The development of the system which simulates the flood forecast area by the SWMM(Storm Water Management System) and hydrology method and displays the danger areas is required for the construction of the inundation forecast system. And the spatial database which contains information of the urban facilities such as the street and building and the sewer system such as the manhole and drainage and the result of the hydrology analysis is constructed. In this paper, we propose the method for transforming the Shape File in ESRI into the Oracle spatial database to construct the spatial data for the drainage systems and urban facilities using the Shape File format in the ESRI. We suggest the algorithm for the transformation of the data format, and develop the prototype system to display the inundation area using the spatial database.

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A Basic Study on Upward Soil Nailing Combined Horizontal Drainage (수평배수공을 겸한 상향식 쏘일네일링 공법의 기초연구)

  • Kim, Hongtaek;Lee, Jungjae;Chung, Jongmin;Choi, Geunhyeok;Lee, In
    • Journal of the Korean GEO-environmental Society
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    • v.10 no.7
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    • pp.151-158
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    • 2009
  • In the early 1990s, soil nailing was first introduced as method of reinforcement for the slope stability and ground excavation, and as its application was increased the improved soil nailing was also developed. Most recently used for grout soil nailing greatly improve the methods and techniques for self-improvement techniques are classified as soil nailing. As the representative for the grout pressure method to improve the join method pressure grouting and improved method for the self-drilled soil nailing, removable soil nailing, upward soil nailing combined with horizontal drainage system. This paper is to compare upward soil nailing combined with horizontal drainage system with downward direction of the soil nailing. In order to study the limit equilibrium slope stability analysis and comparison with factor of safage, excavation for the vertical displacement for comparison with continuous analysis. According to this study, safage factor is decreased considerably using limit equilibrium analysis and makes no odds for the horizontal displacement when soil nail was installed upward.

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Treatment of Peritonsillar Abscess: Needle Aspiration versus Incision and Drainage

  • Cho, Seung-Hyun;Kwon, Soon-Young;Lee, Seung-Hoon;Cho, Jae-Hoon;Choi, Ji-Ho;Baik, Seung-Hoon;Yoo, Chan-Kee
    • Korean Journal of Bronchoesophagology
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    • v.13 no.1
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    • pp.19-22
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    • 2007
  • Background and Objectives: The Objective of this study was to compare the effectiveness of the needle aspiration method and the I&D method in the treatment of peritonsillar abscess. Materials and Methods: A prospective clinical study was performed on 83 patients. All the patients were hospitalized after random treatment with either I&D or needle aspiration alone, received the same intravenous antibiotic therapy. Among the 83 patients, 73 patients who could be observed for longer than 6 months and had not undergone a tonsillectomy during the follow-up period, were analyzed for treatment outcomes. Results: There was no statistically significant difference in the initial failure rate(p=0.572), the hospitalized days(p=0.956), the recurrence rate(p=0.531) for the needle aspiration(35 patients) and I&D groups(38 patients). But, The mean duration of fever were statistically different in the needle aspiration(1.51 hours) and I&D groups(3.05 hours) (p=0.031). Conclusion: Two methods are thought to be similar in effectiveness, except that duration of fever was longer in the I&D group than in the needle aspiration group. However, taking advantages of the needle aspiration method into consideration, the needle aspiration of peritonsillar abscess may be more appropriate than I&D as an initial method for peritonsillar abscess

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