• Magazine of the Korean Society of Agricultural Engineers
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• v.34 no.E
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• pp.12-19
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• 1992

The effects of drainage system on evapotranspiration and drainage flows are studied. Data from drainage field experiment at Castalia in North Central Branch, Ohio Agricultural Research and Development Center were used in this study. A water table management model, ADATP (Agricultural Drainage and Pesticide Transport), which was developed by combining the GLEAMS and the subsurface drainage part of the DRAINMOD model with several modifications, was evaluated and used to predict hydrologic components. The ET is very much affected by the presence of tile drainage system but not significantly affected by the surface drainage system. The combined surface and subsurface drainage system gives the largest total outflow values while the surface drainage only system gives the smallest. Comparisons of model predicted and measured values of surface runoff only, subsurface drainage only, and combined surface runoff and subsurface drainage system are in satisfactory agreement. The model predicted values are within the range of the variations of the observed replications in general. Based on the results of the model evaluation study, it is concluded that ADAPT model can be used to design water table management systems.

• Journal of Korean Tunnelling and Underground Space Association
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• v.8 no.1
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• pp.13-20
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• 2006

This study proposes a new concept of a tunnel central drainage system by using a drain board to make a breakthrough on difficulties in the installation of conventional drainage system and draw-down of its drain capacity especially in long tunnels. A fundamental study has been performed for evaluation of the drain capacity of the planar drainage system adopted in this study. In fact, the system proposed makes possible to omit the side, transverse as well as central drainage pipes required in the conventional system, even if its drain capacity and any guideline for design are not available to date. In this circumstance, it is carried out to investigate the correlation between drain capacities and, shapes and posit ions of the columns of the drain board in terms of a variety of water inflows through hydrological model tests. It is shown from the tests that a drain capacity is highly influenced by the shape and the distance between the columns of a drain board in flowing direction, and a round rectangular shape of the columns leads to the highest capacity of drainage. And also, the shorter distance between the columns in flowing direction, the higher drain capacity would be achieved.

• Geomechanics and Engineering
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• v.17 no.2
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• pp.181-194
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• 2019

Due to the seepage of groundwater, the resisting force of slopes decreases and the sliding force increases, resulting in significantly reduced slope stability. The instability of most natural slopes is closely related to the influence of groundwater. Therefore, it is important to study slope stability under groundwater seepage conditions. Thus, using a simplified seepage model of groundwater combined with the analysis of stresses on the slip surface, the limit equilibrium (LE) analytical solutions for two- and three-dimensional slope stability under groundwater seepage are deduced in this work. Meanwhile, the general nonlinear Mohr-Coulomb (M-C) strength criterion is adopted to describe the shear failure of a slope. By comparing the results with the traditional LE methods on slope examples, the feasibility of the proposed method is verified. In contrast to traditional LE methods, the proposed method is more suitable for analyzing slope stability under complex conditions. In addition, to facilitate the optimization of drainage design in the slope, stability charts are drawn for slopes with different groundwater tables. Furthermore, the study concluded that: (1) when the hydraulic gradient of groundwater is small, the effect on slope stability is also small for a change in the groundwater table; and (2) compared with a slope without a groundwater table, a slope with a groundwater table has a larger failure range under groundwater seepage.

• Journal of the Korean Geographical Society
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• v.39 no.6 s.105
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• pp.833-844
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• 2004

In Chugaryeong rift valley, lava plateau formation by the fissure eruption had vanished original landforms and effected on drainage derangement and revision. 4 rivers including Namdae-cheon, Bukhan-gang, Imjin-gang and Hantan-gang watersheds have shared Cheolwon-Pyeonggang lava plateau, that is, ownerless watershed. Main agency of the dividing process are central-eruption volcanic peaks such as Orisan(453m) and 680 Peak. Especially, Orisan has played the role of divide point for 4 watersheds. In the lower-relief plateau zone, complex drainage system have caused continually river capture between neighboring watersheds. In more elevated range slope, river capture have proceeded to headward erosion. Hydrogeomorphologically, lava-filled valley has initiated decrease of the original size of flood plain, maybe, causing higher capability of inundation by heavy rains, and then more active dissection of lava plateau layer.

• The KSFM Journal of Fluid Machinery
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• v.19 no.3
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• pp.19-24
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• 2016

Oil sands are a mixture of sand, clay, and a high-viscosity petroleum called bitumen. Steam-Assisted Gravity Drainage (SAGD) is the most viable and environmentally safe recovery technology for extracting bitumen. It extracts the viscosity-lowered bitumen by high pressure, high temperature steam injected into the bitumen reservoir. The steam is produced at the Central Processing Facility (CPF). Typically, more than 90% of the energy consumed in producing bitumen are used to generate the steam. Fuels are employed in the process, which cause economic and environmental problems. This paper explores the retrofit of heat exchanger network to reduce the usage of hot and cold utilities. The hot and cold utilities are reduced respectively 6% and 37.3% which in turn resulted in 5.3% saving of total annual cost by improving the existing heat exchanger network of the CPF.

• International Journal of Advanced Culture Technology
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• v.8 no.2
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• pp.260-269
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• 2020

The Steam Assisted Gravity Drainage (SAGD) process is an enhanced method to extract oil from bitumen which involves surface and central process facilities. This paper describes the Central Process Facilities (CPF) of SAGD and proposes several retrofit plans to the Heat Exchanger Network (HEN). In this approach, the process integration scheme is applied to estimate the energy saving in HENs, and various cases are modeled in favor of a commercial simulator. Throughout this work, a minimum approach temperature of 10℃ is assumed. The results reveal that, due to the HEN optimization using process integration, the heating and cooling duties can be reduced to 29.68MW and 1.886MW, respectively. Compared with the Husky case, all cases considered in this study indicate a potential reduction of at least 6% in total cost, including investment and operation costs.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.11
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• pp.4875-4883
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• 2016

Background and objective: Breast cancer-related lymphoedema (BCRL) is a disabling complication with long term impact on quality on life after breast cancer treatment. Its management remains a major challenge for patients and health care professionals; the goal of this overview was to summarize effects of different treatment strategies for patients with BCRL. Methods: A thorough search was undertaken to allow a systematic review or meta-analysis of treatments for BCRL. Two investigators independently selected studies and abstracted the data. Results: Combined physical therapy (CPT) with different combinations of surgery, oral pharmaceuticals, low-level laser therapy, weight reduction, mesenchymal stem cell therapy, kinesio tex taping, and acupuncture might be effective in reducing lymphoedema, but exercise demonstrated no obvious benefit. The results of direct comparisons showed CPT might be more effective than standard physiotherapy (ST). Manual lymphatic drainage (MLD) may not offer additional benefits to ST for swelling reduction, but could facilitate compression bandaging. MLD seemed to have similar effects with self-administered simple lymphatic drainage (SLD) or using an intermittent pneumatic compression pump (IPC). IPC might also not be associated with additional effectiveness for CPT. Efficacy of stem cell therapy vs. compression sleeve or CPT, as well as the effects of daflon and coumarin could not be established. Conclusion: Although many treatments for BCRL might reduce lymphoedema volume, their effects were not well established. The quality of many of the original studies in the included reviews was not optimal, so that in future randomized control trials are a high priority.

• Proceedings of the KGS Conference
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• 2004.11a
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• pp.47-47
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• 2004

• The Journal of the Korean dental association
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• v.5 no.1
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• pp.63-66
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• 1964

A case of 20-year-old man involving a dens in dents with dentoalveolar abscess in the symphysis has been presented. 1. The patient pressented free drainage through the fistulous opening onn labial gingiva in area of left mandibular dentral and lateral incisors. 2. Roentgenographs revealed roentgenolucent shadows around left mandibular central and lateral incisors, dens in dente, was noticed.

• BMB Reports
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• v.39 no.2
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• pp.178-182
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• 2006

Four strains of Acidithiobacillus ferrooxidans with different iron oxidation capacity were isolated from different mine drainage stations. The 16S rRNA gene of these strains were cloned and sequenced. Based on our sequences analysis on the four strain and the data on the other strains deposited in Genbank, all A. ferrooxidans may be classified into three phylogenetic groups. The analysis data showed that nucleotide variables (signature sites) were detected in 21 positions, and most of them were found in the first 800bp from 5' terminal except position 970 and 1375. Interestingly, the first 13 signature sites were located in two main regions:the first region (position 175-234) located in V2 while the second region (position 390-439) were detected in constant region between V2 and V3. Furthermore, the secondary structure and minimal free energy were determined in two regions among strains of three groups. These results may be useful in characterizing the microevolutionary mechanisms of species formation and monitoring in biohydrometallurgical application.