• Archives of Plastic Surgery
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• v.48 no.2
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• pp.175-178
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• 2021

The umbilicus is an important aesthetic component of the abdomen; therefore, its absence is both cosmetically and psychologically distressing to the patient. However, loss of the umbilicus during abdominal surgical procedures is often unavoidable. Umbilical reconstruction is aimed at obtaining a natural, three-dimensional appearance. We propose a simple method for immediate umbilical reconstruction with good long-term results. This technique was used successfully on a patient who underwent tumor excision. A 49-year-old woman presented with a large mass, measuring 5.8×4.0 cm, on her umbilicus. The mass, an epidermal cyst, developed after laparoscopic uterine myomectomy 5 years earlier. Complete excision of the mass resulted in a large defect, and immediate umbilical reconstruction was planned. Our procedure involved apposing and anchoring two opposing flaps onto the abdominal wall, so that the umbilicus would retain its depth over a long period of time. Negative-pressure wound therapy was applied for 72 hours as a mild compressive dressing. No complications were encountered. The healing process was uneventful and the aesthetic outcome was pleasing; a natural-appearing navel was created. The patient was satisfied with the end result. This technique provides a permanent and sufficient depression for the umbilicus.

• Tribology and Lubricants
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• v.36 no.6
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• pp.359-364
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• 2020

Numerical investigation of the groove trap effect with variation in the groove-edge radius of curvature is presented here. The trap effect is evaluated in a two-dimensional sliding bearing using computational fluid dynamics (CFD). This simulation is based on the discrete phase model (DPM) and standard k - ε turbulence model using commercial CFD software, FLUENT. The numerical results are evaluated by comparisons with streamlines and particle trajectories in the grooves. Grooves are applied to various lubrication systems to improve their lubrication characteristics, such as load carrying capacity increment, leakage reduction, frictional loss reduction, and preventing three-body abrasive wear due to trapping effect. This study investigates the grove trapping effect for various groove-edge radius of curvature values and Reynolds numbers. The particle is assumed to be made of steel, with a circular shape, and is injected as a single particle in various positions. One-way coupling is used in the DPM model because the single particle injection condition is applied. Further, the "reflect" condition is applied to the wall boundary and "escape" condition is used for the "pressure inlet" and "pressure outlet" boundaries. From the numerical results, the groove edge radius is found to influence the groove trap effect. Moreover, the groove trap effect is more effective when applying the groove edge radius.

• Structural Engineering and Mechanics
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• v.77 no.6
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• pp.819-830
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• 2021

To evaluate the performance of concrete load bearing walls in a structure under horizontal loads after being exposed to real fire, two steps were followed. In the first step, an experimental study was performed on the thermo-mechanical properties of concrete after heating to temperatures of 200-1000℃ with the purpose of determining the residual mechanical properties after cooling. The temperature was increased in line with natural fire curve in an electric furnace. The peak temperature was maintained for a period of 1.5 hour and then allowed to cool gradually in air at room temperature. All specimens were made from calcareous aggregate to be used for determining the residual properties: compressive strength, static and dynamic elasticity modulus by means of UPV test, including the mass loss. The concrete residual compressive strength and elastic modulus values were compared with those calculated from Eurocode and other analytical models from other studies, and were found to be satisfactory. In the second step, experimental analysis results were then implemented into structural numerical analysis to predict the post-fire load-bearing capacity response of the walls under vertical and horizontal loads. The parameters considered in this analysis were the effective height, the thickness of the wall, various support conditions and the residual strength of concrete. The results indicate that fire damage does not significantly affect the lateral capacity and stiffness of reinforced walls for temperature fires up to 400℃.

• Nuclear Engineering and Technology
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• v.54 no.5
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• pp.1890-1901
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• 2022

We have assessed the applicability of the thermal-hydraulic system analysis code, SPACE, to a small modular reactor called SMART. For the assessment, the experimental data from a scale-down integral-test facility, SMART-ITL, were used. It was conformed that the SPACE code unrealistically calculates the safety injection flow rate through the CMT and SIT during a small-break loss-of-coolant experiment. This unrealistic behavior was due to the overprediction of interfacial heat transfer at the steam-water interface in a vertically stratified flow in the tanks. In this study, a special thermal-hydraulic component model has been developed to realistically calculate the interfacial heat transfer when a strong non-equilibrium two-phase flow is formed in the CMT or SIT. Additionally, we developed a special heat structure model, which analytically calculates the heat transfer from the hot steam to the cold tank wall. The combination of two models for the tank are called the special component model. We assessed it using the SMART-ITL passive safety injection system (PSIS) test data. The results showed that the special component model well predicts the transient behaviors of the CMT and SIT.

• Journal of the Korean Society of Propulsion Engineers
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• v.26 no.6
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• pp.53-61
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• 2022

The estimation method of combustion efficiency has been introduced by using closed bomb test(CBT). The Noble-Abel equation of state was applied to consider the real gas effects to take account of high operation pressure about a couple of 100 atm. of CBT. The heat loss through the CBT wall was considered. The volume change of grain was calculated by applying form functions, which estimated combustion efficiency of 8 different gain shapes. The combustion estimation method proposed in this study was fairly validated by the comparision with the pressure-time history data of the CBT experiments. The effects of both grain shape and propellant loading density were analyzed.

• The Journal of the Society of Stroke on Korean Medicine
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• v.10 no.1
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• pp.54-61
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• 2009

Arteriosclerosis is a pathologic term that contains hardening of arterial wall, loss of arterial elasticity and stenosis of artery. To diagnose this disease, conventional angiography, MRA, transcranial doppler ultrasonography are commonly used. And it causes various clinical phases by a region of the disease. In oriental medicine, arteriosclerosis is classified into congested fluids(痰飮), blood stasis(瘀血), stagnation of Gi(氣滯) and treated by Herb-Med, acupuncture, cupping, moxibustion, and the like. The purpose of this study was to investigate the effect of oriental medical therapy on cerebral arteriosclerosis. A patient with cerebrovascular disease admitted due to dizziness, mild dysarthria, tinnitus, anxiety disorder and his Brain MRA showed severe arteriosclerosis in right anterior cerebral artery(ACA) and middle cerebral artery(MCA). Every day, we administered to patient Herb Med and Herb pills. Also, acupuncture, moxibustion were done, too. As a result of the treatment, the patient's follow up Brain MRA showed improved state of ACA stenosis.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.277-278
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• 2018

Improvement of insulation performance of buildings is a major part. Adiabatic method The adiabatic method minimizes the heat loss of the building. External insulation uses insulation to prevent fire. Ambient air hazards are less prone to fire. When a fire occurs, a phenolic pattern is formed and bond strength with the wall increases. EPS insulation and phenol foam were used to compare external heat transfer and external heat transfer. The heat transfer properties of phenolic foam and styrofoam were evaluated as follows. In the mortar and styrofoam structure, the problem of styrofoam reaching the burning point occurred before the collapse of the mortar, and the phenol foam had a problem in that when the direct fire was continued on the phenol foam. The characteristics of continuous infiltration appeared. In the case of mortar and phenol foam + styrofoam, the heat penetrated into the interior due to the shrinkage due to the shrinkage of the carbon screen on the phenol foam. However, when reinforced with glass mesh on the outer surface, And to reduce infiltration.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.21 no.3
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• pp.359-370
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• 2023

The thermal integrity of spent nuclear fuels has to be maintained during their long-term dry storage. The detailed temperature distributions of spent fuel assemblies are essential for evaluating the integrity of their dry storage systems. In this study, a subchannel analysis model was developed for a canister of a single fuel assembly using the COBRA-SFS code. The thermal parameters affecting the peak cladding temperature (PCT) of the spent fuel assembly were identified, and sensitivity analyses were performed based on these parameters. The subchannel analysis results indicated the presence of a recirculation flow, based on natural convection, between the fuel assembly and downcomer region. The sensitivity analysis of the thermal parameters indicated that the PCT was affected by the emissivity of the fuel cladding and basket, convective heat transfer coefficient, and thermal conductivity of the fluid. However, the effects of the wall friction factor of the canister, form loss coefficient of the grid spacers, and thermal conductivities of the solid materials, on the PCT were predominantly ignored.

• Conservation Science in Museum
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• v.3
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• pp.43-50
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• 2001

This article is about a joint project carried out by the National Museum of Korea and the Tokyo Cultural Properties Research Institute for the conservation of central Asia Wall painting that has been selected for the exhibition at the new Seoul National Museum of Korea at Yongsan. The investigation of the wall painting revealed very useful information. This includes the condition of the object, and the identification of evident damage, such as cracks, loss of pigment, plus materials and methods employed during the object's creation, as well as previous conservation treatment. The object was mainly made by applying plaster to the body (wall) that consisted of a mixture of soils and rice straws. Then, on the surface of the wall-painting, pigments were used to draw and to colour it. As a part of the investigation, radiocarbon dating was conducted using straw samples taken from the object. The result indicates that the object is probably dated form between the end of the 10th Century and the beginning of the 13th Century. The result of X-ray diffraction also revealed the composition of the pigments used on the surface. These are 1. gypsom [Ca(SO₄)·2H₂O], CaSO₄ and Calcite (CaCO₃) and Calcite (CaCO₃) that were used for the white background. 2. Pb₃O₄ and led Arsenate [Pb(As₂O₆) that were used for the red colouring. 3. Cuprite (Cu₂O), Arsenolite (As₂O₃) and Arsenic Oxide (As₂O₄) that were used for the green colouring.

• Nuclear Engineering and Technology
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• v.18 no.3
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• pp.200-208
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• 1986

The loss of coolant accident based on a double-ended cold leg break is analyzed with the discharge coefficient (Ca) of 0.4. This analysis covers the whole transient period from the start of depressurization to the complete refilling of the core by using RELAP4/MOD6-EM and RELAP4/ MOD6-HOT CHANNEL for the system thermal-hydraulics and the fuel performance during the blowdown phase respectively, and RELAP4/MOD6-FLOOD and TOODEE2 during the reflood phase. A simple analytical method has been developed to account for the lower plenum filling by approximating steam-water countercurrent flows and superheated wall effects at the downcomer during the refill period. Based on the informations. at the time of EOB (end-of-bypass), the refill duration time and the initial reflooding temperature were estimated and compared with the results from the RELAP4/MOD6, resulting in a good agreement. In addition, some parametric studies on the EOB were performed. The form loss coefficient between upper head and upper downcomer was found to be sensitive to the occurrence of the spurious EOB. Appropriate form loss coefficients should be taken into account to avoid the flow oscillations at the downcomer. The analyses with the six and three volume core nodalizations, respectively, show much similar trends in the system thermal-hydraulic performance, but the former case is recommended to obtain good results.