• Geotechnical Engineering
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• v.3 no.1
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• pp.7-24
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• 1987

Preloading surcharge method along with vertical drains was adopted to improve the performance of a very soft marine clay deposit. The onshore deposit, located in the Ulsan Bay area, consists of a 2 to 10m thick, very soft, highly compressible marine clay layer developed just below. the sea water level. The initial undrained shear strength of the clay layer was about 0.6 ton/m2. But, the deposit was designed after treatment to support some auxiliary facilities for a new ilo refinery plant, requiring bearing capacities of 3.6 to 5.4 ton/m2 and maximum allowablee settlement of less than 7.5cm. A total of 35, 000 wick drains Ivas installed to expedite drainage during preloading, and surcharge loads of up to 5m above the original ground level were applied in a step-by-step loading sequence to prevent ground failure by excess surcharge loads. An extensive program of field instrumentation was implemented to monitor the behavior of the clay deposit. Measurers!ends included settlements, excess pore pressure and its dissipation, ground farmer level fluctuation, and lateral movement of the so(t clay layer under the preloads. This paper describes the design concepts, construction methods and control procedures used for improvement of the clay layer. It also presents the ground behavior measured during construction, rind comparisons with theoretical predictions.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.4
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• pp.1539-1541
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• 2012

Cholangitis is relatively uncommon but associated mortality is high due to the predisposition in people with underlying disease. For this recognition of contributing risk factors is necessary. Therefore, the present descriptive-analytical cross-sectional survey was designed to determine contributing risk factors for post-ERCP cholangitis in patients with pancreatic cancer. From 2005 to 2010, 110 consecutive cases of pancreatic cancer attending to a tertiary referral centre (Taleghani Hospital), Tehran, Iran were recruited. The patients all underwent stenting via endoscopic retrograde cholangiopancreatography (ERCP). On univariate analysis, a metallic stent type (95% confidence interval (CI) 1.025-11.34, P=0.037), having no jaundice (1.44-2.22, P=0.009), having no pain (1.32-1.91, P=0.026), a history of prior ERCP (1.16-10.37, P=0.020), and having a proximal biliary stone (1.002-5.93, P=0.046) were related to cholangitis. However on multivariate analysis, none of these factors were found to be contributing risk factors. Cholangitis is avoidable with adequate biliary drainage. Because success rates are higher and complication rates lower for endoscopists performing large volumes of ERCP, performance of the procedure should be concentrated as much as possible in institutions with endoscopists having adequate experience. Patients with a high risk for complications may be best served by referral to an advanced center.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.198-201
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• 2001

Porous structures of aluminum foam have been studied by using return aluminum scrap. The apparent foam shape, foam height, density, pore size and their distributions in various section areas of the experimental samples have been investigated. The sample have been cast into metallic mold, using aluminum foam prepared from a precursor based on pure Al ingot and return aluminum scrap mixed with various amounts of 1-2wt% increasing viscosity and foam agent materials. The process provides for flexibility in design of foam structures via relatively easy control over the amount of hydrogen evolution and the drainage processes which occur during foam formation. This is facilitated by manipulating parameters such as the foaming agent, thermal histories during solidification and mix melt viscosities. A metal for producing the foamed are decomposing a foaming agent in a molten metal such that there is an initial and a subsequent expansion due to foaming agent. It has been found that the Al porous foaming with variation amount of 1∼2wt% foam agent and at 2min holding time, which melting temperature has appeared homogeneous pore size at 650∼700$^{\circ}C$. The compression strength were 10-13 kg/min at 125ppi, and increased by higher pore density. The acoustical performance of the panel made with the foamed aluminum is considerably improved; its absorption coefficient shows NRC 0.6-0.8. It has been found that the Al foam is very preferable for the compactness of the thermal system.

• Journal of the Korean Wood Science and Technology
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• v.43 no.6
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• pp.714-720
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• 2015

Since physical and mechanical properties of wood are affected by environmental factors such as soil and climate change, this study investigated relationships between wood quality factors and stand characteristics of Castanopsis cuspidata var. sieboldii forest in the southern region of Korea, including Jeollanam-do Province and Je-ju island. The obtained results found very close relationships between physical and mechanical properties of wood and stand characteristics. The air-dried density and strength performance of woods showed a negative correlation with the diameter at breast height (DBH) while they were positively related to altitude and drainage of the forest site. And wood properties showed variations depending on the region. These results brought a conclusion that wood of Castanopsis cuspidata var. sieboldii in the southern region could be useful forest resources for timber production.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06a
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• pp.111-116
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• 2006

The microstickes control effects of some fixing agents, including an inorganic PAC, an organic polyamine (PA) and polydiallydimethyl ammonium chloride (Pdadmac), and a high cationic starch (HCS), were investigated, together with their effects on wet end performances and physical properties of handsheets. Despite that the HCS and Pdadmac had lower cationic charge densities than the PA and PAC (the HCS being even lower), they gave higher zeta potentials to fibers, and lower turbidities, cationic demands and residual COD contents to the pulp liquid phases than the PA and PAC did. In all cases, the HCS showed even better effects than the Pdadmac. In addition, drainage speed was also much higher by the HCS treatments although paper formation was worsened. All the phenomena showed that the HCS can fix more dissolved and colloidal substances to cellulose fibers, indicating that the HCS functioned mainly with flocculation and even hydrogen bonding mechanisms. Data on optical properties further indicated that the HCS interacted preferentially with colloidal substances, since it fixed more 'dirty' microstickes to fibers which decreased more sheet brightness while increasing more sheet opacity (with both higher light absorption and scattering coefficients). Interestingly, the organic fixing agents did not decrease tensile, tearing, and folding strengths of paper sheets made from 100% recycled newsprint pulp, except when they were dosed in high amounts. On the contrary, the inorganic PAC had more serious negative effects on the strength properties, especially on folding endurance. The study suggested that proper use of the HCS can lead to better microstickies control effects than traditional agents and methods.

• Proceedings of the KIEE Conference
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• 2015.07a
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• pp.1202-1203
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• 2015

This paper describes the development of HVDC ${\pm}500kV$ polypropylene laminated paper (PPLP) mass-impregnated (MI) type cable system for HVDC transmission lines. As you know, mass-impregnated type cable generally has only insulating layer with the Kraft paper impregnated with a high-viscosity insulating compound. But polypropylene laminated paper is made of a layer of extruded polypropylene (PP) film sandwiched between two layers of Kraft paper. Thanks to PP film and its combination with Kraft paper, PPLP has higher AC, Impulse (Imp.) and DC breakdown (BD) strengths as well as lower dielectric loss than conventional Kraft paper insulation. In addition, Kraft MI cable has a limitation for the maximum conductor temperature as $55^{\circ}C$ But this PPLP MI cable has higher maximum conductor temperature than that of Kraft MI cable due to advantage of oil drainage characteristics. It is the most economic type of cable for HVDC transmission. Also HVDC ${\pm}500kV$ PPLP MI cable system was developed including land joints and outdoor-terminations. In order to prove the mechanical and electrical performances, the type test was carried out according to CIGRE recommendations. A full scale cable system has been tested successfully. And additional load cycle and polarity reversal tests on the cable system showed a higher performance compared with a similar mass impregnated paper cable.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.10
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• pp.6061-6064
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• 2013

Objective: To explore the feasibility of pulmonary lobectomy combined with pulmonary arterioplasty by complete video-assisted thoracic surgery (VATS) in patients with lung cancer, and summarize its surgical methods. Materials and Methods: Twenty-one patients with lung cancer in Beijing Chest Hospital Affiliated to Capital Medical University from Feb., 2010 to Jun., 2013 were selected, males and females accounting for 15 and 6 cases, respectively. Ten underwent right upper lobectomy, 5 right lower lobectomy, 4 left upper lobectomy (in which left upper sleeve lobectomy was conducted for 2) and 2 left lower lobectomy. At the same time, local resection of pulmonary arterioplasty was performed for 12 patients, and sleeve resection of pulmonary arterioplasty for 9. Results: Twenty-one patients recovered well after surgery. Thoracic drainage tube was maintained for 3-8 days, with an average of 4.9 days, and hospital stays were 8-15 days, with an average of 11 days. There were no deaths in the perioperative period, and the complications like pulmonary embolism, bronchopleural fistula, chest infection and pulmonary atelectasis did not occur after surgery. Conclusions: Performance of pulmonary lobectomy and pulmonary arterioplasty together by complete VATS is a safe and effective surgical method, which can expand the indications of patients with lung cancer undergoing thoracoscopic pulmonary lobectomy, and make more patients profit from such minimally invasive treatment.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.3
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• pp.427-437
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• 2016

The objective of this study is to develop the regional regression models based on the physiographical and climatological characteristics for estimating flow duration curve (FDC) in ungauged bsisns. To this end, the lower sections with duration from 185 to 355 days of FDCs were constructed from the 16 gauged streamflow data, which were fitted to the two-parameter logarithmic type regression equation. Then, the parameters of the equation were regionalized using the basin characteristics such as basin area, basin slope, drainage density, mean annual precipitation, mean annual streamflow, runoff curve number in order that the proposed regression model can be used for ungauged basin. From the comparison of the estimated by the regional regression model with the observed ones, the model with the combination of basin area, runoff curve number, mean annual precipitation showed the best performance.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.14 no.2
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• pp.189-200
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• 2016

The Republic of Tajikistan has ten former uranium mining sites. The total volume of all tailings is approximately 55 million tonnes, and the covered area is more than 200 hectares. The safe management of legacy uranium mining and tailing sites has become an issue of concern. Depending on the performance requirements and site-specific conditions (location in an arid, semiarid or humid region), a cover system for uranium tailings sites could be constructed using several material layers using both natural and man-made materials. The purpose of this study is to find a feasible cost-effective cover system design for the Degmay uranium tailings site which could provide a long period (100 years) of protection. The HELP computer code was used in the evaluation of potential Degmay cover system designs. As a result of this study, a cover system with 70 cm thick percolation layer, 30 cm thick drainage layer, geomembrane liner and 60 cm thick barrier soil layer is recommended because it minimizes cover thickness and would be the most cost-effective design.

• Ecology and Resilient Infrastructure
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• v.2 no.1
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• pp.93-98
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• 2015

Acid mine drainage (AMD) producing mine tailings can be beneficially recycled to generate electricity by applying fuel cell technology. Pyrite-containing mine tailings and indigenous bacteria from abandoned mine areas were used to construct fuel cells to investigate the effect of pyrite contents and the presence of iron-oxidizing bacteria. The results showed an enhanced electrical performance with a higher content of pyrite in mine tailings. The inoculation of the indigenous bacteria also enhanced the current density by about three times, and the power density by about 10 times. Overall, this study shows that the combined use of the ecological function of indigenous bacteria from mine areas and mine-tailings in fuel cells does not only contribute to reducing harmful effects of mine tailings but also generate electricity.