• Journal of the Korean Society for Railway
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• v.13 no.4
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• pp.363-370
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• 2010

This paper describes the evaluation of structural integrity and dynamic characteristic of inertial load test equipments for performance test of railway vehicle propulsion control system. The propulsion control system of railway vehicle has to be confirmed of safety and reliability prior to its application. Therefore, inertial load test equipments were designed through theoretical equation for performance test of propulsion control system. The structural analysis of inertial load test equipments was conducted using Ansys v11.0 and the dynamic characteristic was evaluated using Adams. The results showed that the structural integrity of inertial load test equipment was satisfied with a safety factor of 10.2 on the bearing part under combined load. Also, the structural stability of flywheel according to dynamic simulation was secured by the maximum oscillation displacement within 0.83mm.

• The Journal of Engineering Geology
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• v.17 no.2 s.52
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• pp.263-270
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• 2007

Tunnel behavior measured by monitoring during construction is a main item for safety evaluation and it depends widely upon local geological characteristics. To assess in this study how much the geological factors influence on tunnel behavior for each RMR factor, a quantification analysis was carried out using tunnel face maps and measurements as explanatory variables and dependent variables, respectively. The results showed that average significance of the influence of RMR factors - R1, R2, R3, R4 and R5, on tunnel displacements are 17.0%, 20.4%, 20.4%, 11.6% and 30.6%, respectively, and this probably indicates that the groundwater condition played a significant role for the tunnel displacement.

• Archives of Plastic Surgery
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• v.38 no.3
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• pp.323-325
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• 2011

Purpose: Breast implant ruptures and displacement are problematic complications after augmentation mammoplasty. The authors report a patient whose cohesive silicone gel implant ruptured and migrated into the pleural cavity after augmentation mammoplasty. Methods: A 23-year-old female had received augmentation mammoplasty at a local clinic a week before visiting our hospital. When the patient's doctor performed a breast massage on the sixth postoperative day, the left breast became flattened. The doctor suspected a breast implant rupture and performed revision surgery. The implant, however, was not found in the submuscular pocket and no definite chest wall defect was found in the operative field. The doctor suspected implant migration into the pleural cavity, and after inserting a new breast implant, the doctor referred the patient to our hospital for further evaluation. The patient's vital signs were stable and she showed no specific symptoms except mild, intermittent pain in the left chest. A CT scan revealed the ruptured implant in the left pleural cavity and passive atelectasis. Results: The intrapleurally migrated ruptured implant was removed by video-assisted thoracic surgery (VATS). There were no adhesions but there was mild inflammation of the pleura. No definite laceration of the pleura was found. The patient was discharged on the first day after the operation without any complications. Conclusion: Surgeons should be aware that breast implants can rupture anytime and the injury to the chest wall, which may displace the breast implant into the pleural cavity, can happen during submuscular pocket dissection and implant insertion.

• Journal of Chest Surgery
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• v.25 no.6
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• pp.621-629
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• 1992

Thirteen sternocosal elevations for pectus excavatum were performed on twelve patients between Jan 1989 and Sep. 1991. Eleven among the twleve patients were male. The subjects ranged in age from 2 years to 20 years, with a mean age of 8.33 years[SD=4.80 years], Eleven patients were below 15 years. The early postoperative evaluation by Humphreys` criteria except keloid formation was excellent in all the patients. The lower vertebral index[LVI], configuration index[CI], and upper vertebral index[UVI] were measured on the lateral chest roentgenogram. The LVI and CI improved significantly from 0.31$\pm$0.06 and 1.14$\pm$0.06 preoperatively to 0.25$\pm$0.03 and 0.78$\pm$1.10 postoperatively. The degrees of depression, flatness, and asymmetry and funnel index were measured at the most deformed portion on the computed tomgram performed pre- and postoperatively. The degrees of depression and funnel index improved significantly from 3.32$\pm$0.73 and 5.77$\pm$1. 54 preoperatively to 1.85$\pm$0.14 and 2.96$\pm$0.43 postoperatively, There was no significant change in the degree of flatness however, Six postoperative morbidities occurred in five patients Three were superficial wound infection, two hemopneumothorax, and one reoeration, Reoperation was performed due to forward displacement of the distal sternum below the posterior sternotomy, The findings of this study suggest that the sternocostal elevation is an excellent primary method for the pectus excavatum of children and young adolescents.

• International Journal of Concrete Structures and Materials
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• v.9 no.1
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• pp.89-118
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• 2015

The geometric nonlinearity of off-diagonal bracing system (ODBS) could be a complementary system to covering and extending the nonlinearity of reinforced concrete material. Finite element modeling is performed for flexural frame, x-braced frame and the ODBS braced frame system at the initial phase. Then the different models are investigated along various analyses. According to the experimental results of flexural and x-braced frame, the verification is done. Analytical assessments are performed in according to three dimensional finite element modeling. Nonlinear static analysis is considered to obtain performance level and seismic behaviour, and then the response modification factors calculated from each model's pushover curve. In the next phase, the evaluation of cracks observed in the finite element models, especially for RC members of all three systems is performed. The finite element assessment is performed on engendered cracks in ODBS braced frame for various time steps. The nonlinear dynamic time history analysis accomplished in different stories models for three records of Elcentro, Naghan and Tabas earthquake accelerograms. Dynamic analysis is performed after scaling accelerogram on each type of flexural frame, x-braced frame and ODBS braced frame one by one. The base-point on RC frame is considered to investigate proportional displacement under each record. Hysteresis curves are assessed along continuing this study. The equivalent viscous damping for ODBS system is estimated in according to references. Results in each section show the ODBS system has an acceptable seismic behaviour and their conclusions have been converged when the ODBS system is utilized in reinforced concrete frame.

• Journal of the Korea Concrete Institute
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• v.25 no.5
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• pp.477-484
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• 2013

In this study, eleven reinforced concrete beams, ground granulated blast furnace slag, replacing recycled coarse aggregate (BRS series) and recycled coarse aggregate with steel fiber (BSRS series), and standard specimen (BSS) were constructed and tested under monotonic loading. Experimental programs were carried out to improve and evaluate the shear performance of such test specimens, such as the load-displacement, the failure mode and the maximum load carrying capacity. All the specimens were modeled in 1/2 scale-down size. Test results showed that test specimens (BSRS Series) was increased the compressive strength by 9%, the maximum load carrying capacity by 1~6% and the ductility capacity by 1.02~1.13 times in comparison with the standard specimen (BSS). And the specimens (BSRS Series) showed enough ductile behavior and stable flexural failure.

• Journal of IKEEE
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• v.22 no.3
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• pp.866-869
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• 2018

This paper presents the analysis of the human driving behavior based on the expression as a GMDH technique focusing on the driver's collision avoidance maneuver. The driving data are collected by using the three dimensional driving simulator based on CAVE, which provides stereoscopic immersive vision. A GMDH is also introduced and applied to the measured data in order to build a mathematical model of driving behavior. From the obtained model, it is found that the longitudinal distance between cars($x_1$), the longitudinal relative velocity($x_2$) and the lateral displacement between cars($x_4$) play important roles in the collision avoidance maneuver under the 3D environments.

• Journal of the Korean Society of Safety
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• v.32 no.5
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• pp.41-46
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• 2017

The coefficient of derailment and the rate of wheel load reduction were used as the index of train running safety that was directly affected the train derailment safety. In aspects of track, the train running safety depends on the complex interaction between wheel and rail, and the track-vehicle conditions (i.e., the curvature, cant, track system, vehicle speed and the operation conditions, etc). In this study, the relationship between the train running safety and the track curvature and vehicle speed for direct fixation concrete tracks currently employed in Korean light rapid transit was assessed by performing field tests using actual vehicles running along the service lines. The measured dynamic wheel load, lateral wheel load and lateral displacement of rail head were measured for same train running on four tested tracks under real conditions, which included curved and tangent tracks placed on the tunnel and bridge, thus increasing the train speed by approximately maximum design speed of each test site. Therefore, the measured dynamic track response was applied to the running safety analysis in order to evaluate the coefficient of derailment, the rate of wheel load reduction and the track gauge widening at each test site, and compare with the corresponding Korean train running safety standard. As the results, the lateral track response of direct fixation concrete track appeared to increase with the decreased track curvature; therefore, it was inferred that the track curvature directly affected the train running safety.

• Journal of the Korean GEO-environmental Society
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• v.18 no.8
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• pp.5-15
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• 2017

To perform an integrated load analysis carried out to evaluate the stability evaluation of wind turbine generators, the six degree-of-freedom stiffness matrix of foundation, which describes relationships between loads and displacement, is needed. Since the foundation stiffness should accurately reflect the shape of foundation and the condition of soil, it is necessary to calculate the stiffness of the bucket foundation that considers the elasto-plastic behavior of the soil. In this study, finite element analyses were performed for a range of soils and shapes of bucket foundations to estimate the foundation stiffness. Normalized stiffness curves are developed from respective numerical simulations. Proposed results are considered to be useful because they can be directly applied in the design.

• Journal of the Korean Geosynthetics Society
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• v.10 no.4
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• pp.49-59
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• 2011

In order to understand evaluation of the seismic stability of a reinforced earth retaining, we made chambers of 1:10 (the ratio of the miniature), considering the law of similarity based on drawings of representative cross sections. And we measured an increase in acceleration, earth pressure, and displacement after applying Hachinohe wave (long period), Ofunato wave (short period), and artificial wave, complying with the domestic standards, in order to evaluate the external stability of the reinforced earth retaining wall during earthquake based on the measurements. As a result, the unreinforced earth retaining wall collapsed at 2 g of seismic acceleration. But the reinforced earth retaining wall was evaluated to ensure proper stability as well, with respect to the earth pressure gauge, the increments of earth pressure tend to be raised significantly in the upper than the lower and showed a similar characteristic of behavior in previous theory.