• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.3
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• pp.907-917
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• 2014

When conducting excavations after burying the soft ground, even if the retaining walls are installed, failure often occurs within backfill. In order to minimize the occurrences of failures, model test was performed after the installation of stabilizing piles to investigate the stabilizing effects. The model chamber is set up with clay foundation reinforced with and without stabilizing piles. During the excavation of clay foundation, the subsidence, pore water pressure, and soil pressure along the excavation were measured. As a result of the model test, the increase of excavation levels and the reduction of subsidence of back ground were observed with the stabilizing piles, compared to those without the stabilizing piles. The installation of stabilizing piles does not influence the pore water pressure change, but induces less subsidence rate. In addition, the depth of excavation has a significant effect on the back ground and it was evaluated that the maximum subsidence occurs as it is closer to the excavation point.

• Archives of Plastic Surgery
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• v.43 no.4
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• pp.339-343
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• 2016

Background Numerous techniques have been used to achieve long-term projection of the nipple following nipple-areola reconstruction. However, the reconstructed nipple loses projection over time. We describe a technique that uses local flaps to improve the lost projection of reconstructed nipples. Methods Between November 2013 and March 2015, nine patients (11 nipples) underwent revisional nipple reconstruction for lost projection. Only C-H nipple reconstructions were included in this study. The medical history of each patient was reviewed and photographs were taken in front and lateral views. All patients attended routine follow-up visits. Deepithelialized triangular flaps were made on all four sides of the nipple and buried in the opposite corners in order to augment the volume of the nipple. Anchoring sutures were used to attach each triangular flap on the side opposite their point of origin, and the resulting defects were closed directly. Results This procedure was used successfully in nine patients (11 nipples). Adequate projection was achieved in all patients and no complications occurred. The average nipple height was 3 mm before operation, 7 mm one day after operation, 5 mm at the six-month follow-up, and 5 mm at the 12-month follow-up. The average nipple-areolar angle was $164^{\circ}$ before the operation, $111^{\circ}$ one day after the operation, $130^{\circ}$ at the six-month follow-up, and $133^{\circ}$ at the 12-month follow-up. Conclusions The method described provides a solution to the loss of projection in reconstructed nipples. We recommend this technique because it leads to better projection, greater volume, and a more natural shape.

• Archives of Plastic Surgery
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• v.35 no.4
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• pp.446-449
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• 2008

Purpose: Pilonidal sinus is a frequent disease that occurs mostly in hairy young men, defined as chronic inflammation and infection of the postsacral sinuses. Wide excision of the affected area is the treatment of choice. Many techniques have been described to cover the defect. However none appears to be the ideal procedure to prevent infection, recurrence, and delayed wound healing. We present the results of an alternative technique that we performed by using partial deepithelized gluteal transposition flap for reconstruction of the defect following wide excision. Methods: From October 2004 to September 2007, we performed the partial deepithelized gluteal transposition flap method on 6 patients. We modified the transposition flap techniques by deepithelialising the medial parts of the flap and burying them under the opposing edge of the flap. The results were compared with previous studies and evaluated regarding duration of surgery, size of defect, hospitalization periods, and complications. Results: All the flaps were healed well with no partial or complete loss of the flap. Hospitalization and immobilization periods were acceptably shortened. Recurrence was not seen. The aesthetic outcome was also satisfactory and all patients were satisfied with the results. Conclusion: The main advantage of our techniques is using healthy tissues to obliterate the dead space, to provide an extra-cushion, and to prevent deep dehiscence. We believe that the partial deepithelized gluteal transposition flap is a good alternative method for treatment of pilonidal sinus.

• Journal of the Korean Geotechnical Society
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• v.21 no.5
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• pp.215-223
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• 2005

Piezo-ceramics are special materials which transform energy from mechanical to electrical forms and vice versa. Bender elements are composite materials consisting of thin piezo-ceramics and elastic shims, and are widely used as actuators and transducers in the field of electronics, robotics, autos and mechatronics utilizing the effectiveness of energy transformation capability. In geotechnical engineering, commercial bender elements are used in laboratory as source and receiver in the measurements of soil stiffness. The elements were built by using various metal shims sandwiched between piezo-ceramics and coating over the composite in the research. A pair of elements were buried in a concrete block and used as source and receiver to measure the stiffness of the concrete. The test results were verified by comparing with the resonant column testing results. In a preliminary stage of the development of an in-situ seismic testing equipment using bender elements for soft clay materials, shear waves were generated and measured by burying the elements in the barrel of kaolinite and water mixture. The measured shear wave signals were so distinct for the first-arrival pick that applicability of the elements in the field measurements could be very promising.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.6
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• pp.68-74
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• 2011

The touch or step voltages which exist in the vicinity of a grounding electrode are closely related to the earth structure and resistivity and the ground current. The grounding design approach is required to determine the grounding electrode location where the hazardous voltages are minimized. In this paper, in order to propose a method of mitigating the electric shock hazards caused by the ground surface potential rise in the vicinity of a counterpoise, the hazards relevant to touch voltage were evaluated as a function of the soil resistivity ratio $\rho_2/\rho_1$ for several practical values of two-layer earth structures. The touch voltage and current on the ground surface just above the test electrode are calculated with CDEGS program. As a consequence, it was found that burying a grounding electrode in the soil with low resistivity is effective to reduce the electric shock hazards. In the case that the bottom layer soil where a counterpoise is buried has lower resistivity than the upper layer soil, when the upper layer soil resistivity is increased, the surface potential is slightly raised, but the current through the human body is reduced with increasing the upper layer soil resistivity because of the greater contact resistance between the earth surface and the feet. The electric shock hazard in the vicinity of grounding electrodes is closely related to soil structure and resistivity and are reduced with increasing the ration of the upper layer resistivity to the bottom layer resistivity in two-layer soil.

• Journal of the Korea Concrete Institute
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• v.14 no.1
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• pp.16-23
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• 2002

In construction field, million tons of demolished concrete are produced in korea. It is urgently needed that they are used as recycled materials in order to prevent environment pollution and gain economic profits. However, existing recycling methods of demolished concrete have their limits for wide application. They have been only focused on the burying and banking. Therefore, in this paper, physical and mechanical properties of planting concrete using construction wastes for aggregates are described in order to investigate the validities of demolished concrete as recycled aggregates. The Properties of strength and durability are tested. According to the experimental results, compressive strength and freeze-thaw resistance of planting concrete using recycled aggregates shows worse performance than those using crushed stone concrete. But, it shows positive performance on the absorption ratio and thermal conductivity. Especially, considering the side of recycling of concrete wastes, it is recommended that recycled aggregates made with construction wastes is applied to planting concrete.

• Journal of the Korean Institute of Landscape Architecture
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• v.22 no.1
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• pp.53-63
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• 1994

There are lots of forests around the Korean rural village. This study was conducted to investigate the state of the forests by the 15 forests case study of the Kamgok region in Chon-guk-Do province, Korea. The results are as follows. 1. The forests lose mostly original form by the construction of road and forest clearing for the land development business. And almostly the form of the forests is a trapezoid or roundness. 2. The forests were remained on account of the Korean cemetery customs which is burying underground. 3. The conservation of the forests becomes more difficult because of the continuous development pressure. 4. Because the scale of the forests is so small, they aren't named as the natural resort forest by the forest law. So it will be the better alternative that they are conserved and used by inducing the concept of the village resort forest. 5. Because the owenership of the forests exists in a person or a family, the forests will be destructed continuously by the cemetery development. 6. The vegetation of the upper trees in the forests is the simple forests of Pinus densiflora, Pinus rigida and bamboo. The height of upper tree is average 10-12m. And average root diameter is 13-29cm. The age of the tree is average 50 years old. The state of the forests is mostly fine. 7. It is clarified that the price of the forest land is 3-5 times expensive than the other cultivated land. 8. The forests were made by the forefathers for the purpose of the practical use and were reforested in the era 1960s, 1970s.

• Resources Recycling
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• v.13 no.2
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• pp.9-15
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• 2004

A large tons of spent iron oxide catalyst come from the Styrene Monomer(SM) production company. It is caused to pollute the land and underground water due to the high alkali contents in the catalyst by burying them in the landfill. In order to recycle the spent catalyst, a basic study on the recovery of chromium ion from metal plating wastewater with the spent catalyst was carried out. The iron oxide catalyst adsorbed physically $Cr^{+6}$ in the lower pH 3.0, that is the isoelectric point of the spent catalyst. It was found that the iron oxide catalyst reduced the $Cr^{+6}$ into Cr+3 by the oxidation of ferrous ion into ferric ion on the surface of catalyst, and precipitated as $Cr(OH)_3$ in the higher than pH 3.0. The $Cr^{+6}$ was recovered 2.0∼2.3g/L catalyst in the range of pH 0.5∼2.0, but it was recovered 1.5 g/L catalyst at pH 3.0 of wastewater. The recovery of Cr was increased as the higher concentration in the continuous process, but the flowrates were nearly affected on the Cr recovery.

• Journal of Sericultural and Entomological Science
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• v.44 no.2
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• pp.74-81
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• 2002

The optimal conditions for mycelial growth of P. linteus ASI 26011 were 25-30$^{\circ}C$ and pH 6.0, respectively. The mycelial growth of P. linteus was excellent on MCM medium. In case of carbon sources, the mycelial growth of P. linteus was best on the culture media that were contained with sucrose, mannose and glucose. Potassium nitrate and sodium nitrate were good for the mycelial growth of P. linteus as a nitrogen source. For comparison of the mycelial colonization of P. linteus on logs, several techniques of inoculation were tested; the sterilized short log inoculation, drilling inoculation and log-end sandwich inoculation. The mycelial colonization of P. linteus on logs was good in the treatment of sterilized short log inoculation, but poor in the traditional methods such as drilling inoculation and log-end sandwich. The initial mycelial growth and the full mycelial colonization of P. linteus were the best on 20 cm logs under the condition of 42% of moisture content in log. Also the initial mycelial growth of P. linteus was accelerated over 12 hours of sterilization. Burying method of logs after 5-6 months of incubation was the best for formation of basidiocarp of P. linteus. The formation of fruiting body of P. linteus was quite good in the cultivation house at the 31-35$^{\circ}C$ and over 96% of relative humidity.

• Journal of Ocean Engineering and Technology
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• v.30 no.4
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• pp.310-319
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• 2016

If a spoiler was attached to the pipeline investigated in a previous study, a strong flow and vortex at the lower part caused scouring and thus an asymmetric pressure distribution, which assisted in the analysis of the self-burial structure where a down force was applied to the pipe. However, only the fluid-pipe interaction was considered, excluding the medium (seabed), when practically burying the pipeline. Thus, this study applied a numerical model (LES-WASS-2D) to directly analyze the non-linear interactions among the fluid, pipe, and seabed in order to perform numerical simulations of a pipeline with a spoiler installed on the seabed. This allowed the self-burial mechanism of a pipeline with a spoiler to be analyzed in the same context as the previous study that considered only the fluid-pipe interaction. However, when a pipeline was installed on the seabed, a strong flow and vortex were found at the front of the bottom, and a spoiler accelerated the fluid resistances. This hydraulic phenomenon will reinforce the scouring and down force on the pipeline. In the general consideration of the numerical analysis results by the specifications and arrangements of the spoiler, a pipeline with a spoiler was found to be the most effective for the self-burial function.