• Journal of the Korean Geosynthetics Society
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• v.22 no.2
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• pp.55-61
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• 2023

This paper describes the comparative results of measured and predicted values for the horizontal displacement of earth retaining wall based on two field cases, In order to examine the application of lateral earth pressure to the earth retaining wall considering the typical ground characteristics (clinker layer) in Jeju. The prediction of the lateral earth pressure causing the horizontal displacement of the retaining wall was performed by elasto-plastic analysis using Rankine earth pressure, Terzaghi & Peck modified lateral earth pressure, and Tschebotarioff lateral earth pressure. As a result, it was confirmed that the maximum horizontal displacement predicted at site A was about 5 times larger than the measured value, and the ground with maximum horizontal displacement occurred by the prediction was found to be the clinker layer. In the case of site B, the predicted value was 4 to 7 times larger than the measured value. In addition, the ground with maximum horizontal displacement and the tendency of horizontal displacement were very different depending on the prediction method. This means that research on lateral earth pressure that can consider regional characteristics needs to be continued, because it is due to the multi-layered ground characteristics of the Jeju area in which bedrock layers and clinker layers are alternately distributed,

• Journal of the Korean Geotechnical Society
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• v.18 no.3
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• pp.33-41
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• 2002

Soil nailing type of retaining structures has been widely used in Korea far the purpose of the temporary and permanent support in excavations and slope stability. The important factors in application of soil nailing systems in urban excavation site nearby the existing structures are the displacement of the wall and tensile farce of the nails, etc. In this paper, the fled back analyses are carried out at 11 excavation sites to investigate the behavior of tensile farce of nails at stepwise excavation in the multi-layered strata including various rock layers. The results of the fled back analysis are less than about 50% of the measured ones. The distance of active zone by measurements are shown almost larger than that of fled back analysis when the distance of active Bone is defined from the surface of wall to the potential failure surface. And the results of fled back analysis are within the range proposed by the project CLOUTERRE and Cartier & Gigan (1983) which were 0.3$H_f$, and 0.5$H_f$, of the final excavation depth ($H_f$,) respectively, but the values of the measurement were larger than these values.

• Journal of the Korean institute of surface engineering
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• v.48 no.6
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• pp.260-268
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• 2015

The thermal barrier coating (TBC) for inner wall of liquid-fuel rocket combustor consists of NiCrAlY as bonding layer and $ZrO_2$ as a top layer. In most case, the plasma spray coating is used for TBC process and this process has inherent possibility of cracking due to large difference in thermal expansion coefficients among bonding layer, top layer and metal substrate. In this paper, we suggest crack-free TBC process by using a precise electrodeposition technique. Electrodeposited Ni-P/Cr double layer has similar thermal expansion coefficient to the Cu alloy substrate resulting in superior thermal barrier performance and high temperature oxidation resistance. We studied the effects of phosphorous concentrations (2.12 wt%, 6.97 wt%, and 10.53 wt%) on the annealing behavior ($750^{\circ}C$) of Ni-P samples and Cr double layered electrodeposits. Annealing temperature was simulated by combustion test condition. Also, we conducted SEM/EDS and XRD analysis for Ni-P/Cr samples. The results showed that the band layers between Ni-P and Cr are Ni and Cr, and has no formed with heat treatment. These band layers were solid solution of Cr and Ni which is formed by interdiffusion of both alloy elements. In addition, the P was not found in it. The thickness of band layer was increased with increasing annealing time. We expected that the band layer can improve the adhesion between Cr and Ni-P.

• Applied Microscopy
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• v.19 no.1
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• pp.59-69
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• 1989

Ultrastructure of the secretory portion of the small ampullate gland in the orb web spider, Nephila clavata, has been investigated using the electron microscope. The secretory portion of this gland comprise two different regions which are a S-shaped storage sac and a long, convoluted tail. By the internal textures of the secretory granules, the sac is subdivided into two regions ; the proximal region near the tail and the distal region near the duct. Commonly single layered connectives cover the basal portion of the sac epithelium, and apical portion of the epithelial cells is occupied by the thick cuticles. Within the epithelial cells of both the proximal and distal region, several types of the secretory granules surrounded by a limiting membrane and had characteristic crystalloid are scattered throughout the cytoplasm. The granular size and its electron densities are not coincide with each other according to the maturation level of the granules. The wall of the tail is composed of single layer of columnar epithelial cells, and their nuclei are found at the basal portion of the cells. Dissimilar to the epithelial cells of the sac, apical cuticles are not found at this portion. In the cytoplasm of these cells, numerous secretory granules, synthesized from the rough endoplasmic reticula commonly and had fine fibrous materials, are found. At the cell surface bordering the lumen, microvilli are seen, arid along the cellular boundaries specialized septate junctions and desmosomes appeared.

• Archives of Plastic Surgery
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• v.37 no.2
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• pp.169-174
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• 2010

Purpose: Reduction mammaplasty is a procedure with a relatively high patient satisfaction rate, however, associated scarring around the areola can be a serious problem. This study proposes a new modification of the breast reduction procedure by means of an inframammary incision alone. Methods: The breast is marked out preoperatively with standing position. Under the general anesthesia, an inframammary incision of approximately 7 - 8 cm is done. The subcutaneous plane is made in the lower pole of the breast, then the subglandular plane is entered and a sharp dissection is made up to 2 cm below the areola. The breast is mobilized from the chest wall and a cone-shaped parenchyme is removed in en-block except from the retroareolar central part. The remaining both pillars are gathered together with absorbable sutures and the base of the gland is narrowed to project the breast forward. The wound is closed in a layered fashion and taping of the breast mound is applied to redistribute the breast skin. Results: 21 patients (36 breasts) underwent this procedure from December 2004 to December 2009. Average follow up was 9 months (ranged from 6 months to 12 months). No major complication occurred. Most patients were pleased with the breast size, shape, and scars. However, 2 patients complained their hypertrophic scars which were corrected by revision. Conclusion: This technique is a simple approach to mild to moderate breast reduction through an inframammary incision alone. And, this technique provides an option with minimal complications and invisible scarring, which is especially important in the young patient group.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.10a
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• pp.481-489
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• 2006

Two dimensional diffusion model test was conducted to investigate the sedimentation properties and consolidation process of reclaimed ground using dredging coarse soil which is composed of passing amount 20 percentage and 45 percentage of #200 sieve size respectively. The passing amount of #200 sieve size affected on sedimentation properties. The coarse soil which is passing amount of 20 percent showed that the sedimentation structure was layered type and passing amount of 45 percentage was wall-partition type according diffusion distance. Furthermore, the water content of surface and section, and distribution of fine soil were changed according to diffusion distance. and the change amount of pore water pressure and strength property when soil is diffused, segregated and accumulated can be applied efficiently in design of dredging and reclamation.

• Journal of Veterinary Clinics
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• v.34 no.5
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• pp.384-387
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• 2017

A dead male Jeju weasel with clinical signs of severe dehydration and moribund was submitted for the necropsy. Grossly, purple-red ecchymoses were scattered in the surface of the entire lungs. Milky-white mucoid materials occupied in the left bronchial lumens. Histopathologically, an adult worm with thick cuticle layer surrounded by chronic inflammatory cells was embedded in the left caudal lung lobe. Numerous oval or barrel-shaped parasitic eggs with muco-purulent exudates were observed in the dilated bronchus of another section of left caudal lobe. Operculate parasitic eggs showed typical morphologic characteristics such as barrel shape with asymmetry bipolar plugs and thick bi-layered wall. Based on the histopathologic findings and morphological characteristics of parasitic eggs in the pulmonary tissue section, this case was diagnosed as verminous pneumonia associated Eucoleus aerophilus infection in Jeju weasel.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.21 no.11
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• pp.1422-1436
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• 1997

Numerical investigations were conducted to study the convective phenomena of an initially stably stratified salt water solution with lateral heating in a uniformly rotating annulus. The method of investigation is the finite difference analysis of the basic conservation equation for an axisymmetric, unsteady, double-diffusive convection and calculation is made for R $a_{\eta}$=2*10$^{5}$ and Ta=10$^{7}$ ~ 2.5*10$^{8}$ . Formation of layered flow structure, merging process of layers, the corresponding temperature and concentration distributions, Nu variation with time are examined. Numerical results show that in each layer, the temperature profile looks 'S'-shaped and the concentration profile is uniform due to the convective mixing. At the interface between adjacent layers, the temperature changes smoothly but the concentration changes rapidly. As the effect of the rotation increases, the generation of rolls at hot wall, the formation and merging of layers are delayed. The average Nu shows the trend of conduction heat transferees the effect of the rotation increases.n increases.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.2
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• pp.191-196
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• 2016

Applying diffraction of waves and muffler principle, the theory of macroscopic air ventilation with soundproofing was explained. Soundproofing frequency range can be selected by this method. The sound wave was attenuated at the resonator located between double-layered walls. A soundproof plate was designed and the experiment was processed. There are two air holes of diameter of 5cm and thickness of 8cm on the surfaces per each soundproofing cell. There was a transmission loss of about 25dB and it is more than at least 10dB compared with that of the Comnex technology of wave cancellation by air holes in Japan. Furthermore, there was no soundproof frequency selection in the Comnex technology.

• Transactions of the Korean Society of Mechanical Engineers
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• v.19 no.7
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• pp.1731-1740
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• 1995

Experimental investigations have been made to study the double-diffusive nature of convection of an initially stratified salt-water solution due to heating from below in a rotating cylindrical cavity. The objective is to examine the flow phenomena and the heat transfer characteristics according to the changes in temperature gradient, concentration gradient and rotating velocity of cavity. Thermal and solutal boundary conditions at side wall are adiabatic and impermeable, respectively. The top and bottom plate are maintained each at constant temperature and concentration. The cavity is put into a state of solid body rotation. Like the stationary case, the types of initially-formed flow pattern are classified into three regimes depending on the effective Rayleigh number and Taylor number; stagnant flow regime, single mixed-layer flow regime and successively formed multi-mixed layer flow regime. At the same effective Rayleigh number, the number of initially-formed mixed layer and its growth rate decrease as the effect of rotation increases. The temperature and concentration profiles are both uniform in each layer due to convective mixing in the layered-flow regime, but look both liner in stagnant flow regime and single mixed-layer flow regime. At the interface between adjacent layers, the temperature changes smoothly but the concentration changes rapidly.