• Structural Monitoring and Maintenance
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• v.5 no.1
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• pp.151-171
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• 2018

Transmission tower-line systems are commonly slender and generally possess a small stiffness and low structural damping. They are prone to impulsive excitations induced by cable rupture and may experience strong vibration. Excessive deformation and vibration of a transmission tower-line system subjected to cable rupture may induce a local destruction and even failure event. A little work has yet been carried out to evaluate the performance of transmission tower-line systems in mountain areas subjected to cable rupture. In addition, the control for cable rupture induced vibration of a transmission tower-line system has not been systematically conducted. In this regard, the dynamic response analysis of a transmission tower-line system in mountain areas subjected to cable rupture is conducted. Furthermore, the feasibility of using viscous fluid dampers to suppress the cable rupture-induced vibration is also investigated. The three dimensional (3D) finite element (FE) model of a transmission tower-line system is first established and the mathematical model of a mountain is developed to describe the equivalent scale and configuration of a mountain. The model of a tower-line-mountain system is developed by taking a real transmission tower-line system constructed in China as an example. The mechanical model for the dynamic interaction between the ground and transmission lines is proposed and the mechanical model of a viscous fluid damper is also presented. The equations of motion of the transmission tower-line system subjected to cable rupture without/with viscous fluid dampers are established. The field measurement is carried out to verify the analytical FE model and determine the damping ratios of the example transmission tower-line system. The dynamic analysis of the tower-line system is carried out to investigate structural performance under cable rupture and the validity of the proposed control approach based on viscous fluid dampers is examined. The made observations demonstrate that cable rupture may induce strong structural vibration and the implementation of viscous fluid dampers with optimal parameters can effectively suppress structural responses.

• Journal of Drive and Control
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• v.11 no.4
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• pp.32-38
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• 2014

The hydraulic fuse, which responds to the suddenly increased flow on rupture of a line and shuts off the fluid flow, would prevent large spillage of liquid. The quick-acting hydraulic fuse, which is mainly composed of a poppet, a seat, and a spring, must be designed to minimize the leaked flow and to prevent high collision speed between the poppet and seat during fuse operation on a line rupture. The optimal design parameters of a quick-acting hydraulic fuse were searched using the genetic algorithm and the complex method that are kinds of constrained direct search methods. The dynamic behavior of a quick-acting hydraulic fuse was researched using computer simulations that applied the obtained optimal design parameters.

• Journal of Chest Surgery
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• v.29 no.3
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• pp.355-359
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• 1996

Rupture of the main bronchus due to blunt chest trauma is very rare, especially In childhood although the incidence is increasing. Early diagnosis and primary repair not. only restore normal lung function but also avoid the difficulties and complications associated with delayed diagnosis and repair. We experienced 2 cases of right main bronchial rupture caused by traffic accidents. Patients suffered from progressively developing dyspnea and subcutaneous emphysema on the neck, anteriorchest,andanteriorabdominalwall. Emergency operations were performed through right posterolateral thoracotomy incision at the 4th intercostal space. Intraoperatively, the right main bronchus completely transsected and separated. Corrective bronchoplasty was performed with end-to-end anastomosis using interrupted suture with 3-0 Vicryle and the suture line was reinforced with azygos vein and parietal pleural flap. Postoperative courses were uneventful and patients discharged without any specific pro lems.

• Aerospace Engineering and Technology
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• v.11 no.2
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• pp.122-128
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• 2012

Many of the liquid rocket engines use a hypergolic igniter with rupture disc ends located in the combustion chamber ignition line. In this study, the flow coefficient tests of the igniter, which have a solenoid valve upstream, were performed. The tension-type rupture discs for radial and circumferential scores and the igniter with them were tested using water at room temperature. The effects of the score, flow rate, the disc thickness, gas pocket and the solenoid valve on the coefficient were analyzed.

• Journal of Korean Foot and Ankle Society
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• v.25 no.2
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• pp.80-88
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• 2021

Chronic Achilles tendon rupture is likely to result in functional impairment in gait and sports activity. The presence of a large defect secondary to retraction of the tendon ends, atrophy of the calf muscles, and vulnerable vascularity of the soft tissue envelope make it a challenging problem to treat. Surgical reconstruction aims to restore the length and tension of the gastrocnemius-soleus complex. Various surgical treatment options have been described, depending on several factors, including residual gap size after scar tissue removal, remaining tissue quality, and vascularity. Despite good results being reported, there is a lack of high-level, evidence-based clinical guidelines available to select the first-line surgical procedure. This paper overviews the current available surgical options for patients with chronic Achilles tendon rupture.

• Journal of the Korean institute of surface engineering
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• v.9 no.3
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• pp.5-8
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• 1976

In this study, a ruture strength of epoxy resin film coated on the leaking spot in waterpipe line was determined, using water pressure, without interrupting water supply. This results could be used for the sealing of water leakage in large size waterpipe lines. An experimental equation {{{{P=Kt^m~ /R^n~ (m=2, n=3.5) }} was also obtained, where P is the rupture pressure, K is constant, t is the thickness and R is the radius of the resin film. From this results, the safe쇼 thickness of the film for a domestic use was calculated with various radii against the maximum pressure.

• Journal of Chest Surgery
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• v.7 no.2
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• pp.163-168
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• 1974

Five cases of traumatic diaphragmatic hernia were repaired in the Department of Thoracic Surgery, Seoul National University Hospital, during the period from 1967 to 1974. The first case, a 14-year aid girl, was diagnosed as diaphragmatic hernia during laparotomy because of jejunal perforation 3 days after traffic accident. Herniated stomach, transverse colon, spleen and left lobe of the liver were repositioned and the diaphragmatic rupture on left posterolateral portion was repaired with two layers of nonabsorbable sutures by transthoracic approach. The second case, a 26-year old man,was diagnosed immediately after traffic accident at a local clinic and transferred to this hospital 24 hours later. Herniated stomach, transverse colon and jejunum were repositioned amd diaphragmatic rupture,about 9 cm in length,from the posterolat.edge to the base of pericardium was sutured in two layers. The third case, a 26-year old man who had stab wound on the left lower lateral chest two years ago,was admitted with sudden abdominal pain and vomiting. Upper gastrointestinal series with barium meal revealed diaphragmatic hernia. The herniated stomach and transverse colon through the defect,about 3.5cm in diameter, at anterolateral portion on the left side,were repositioned and repaired with two layers of nonabsorbable sutures. The forth case, a 26-year old man, sustained blunt trauma to the chest by a roller and was transferred to the emergency room complaining of dyspnea 40 minutes after the accident. The diaphragmatic rupture extended from left midaxillary line to contralateral anterior axillary line,about 20cm long, at anterior portion of diaphragm, which was repaired with two layers, of nonabsorbable sutures. The fifth case, a 4-year old girl, had two separate diaphragmatic ruptures on both sides, which were caused by traffic accident. Immediate upper gastrointestinal series after injury showed herniated stomach, colon and spleen into left Chest cavity. Another small rupture with anterior edge of right lobe of the liver in chest cavity was noted. These were repaired with non-absorbable sutures via thoracotomy.

• Journal of Chest Surgery
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• v.21 no.3
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• pp.547-552
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• 1988

Rupture of the main bronchus followed by blunt chest trauma is comparatively very rare. Early recognition of bronchial rupture and emergency thoracostomy and management is essential for reducing of morbidity and mortality and late complications. This case was 11 years old female who was a primary school student. The patient was sustained a crushing injury to her right hemithorax by traffic accident and had been taken emergency closed thoracostomy at her second intercostal space, midclavicular line at emergency room. In the course of the next 2 hours, the girl`s condition remained critical with tension pneumothorax and abnormal arterial blood gas analysis. Induction of anesthesia started 3 hours after the accident. During the general anesthesia, cardiac arrest was occurred and cardiac resuscitation was performed. Right upper lobectomy and end-to-end anastomosis of ruptured right main bronchus was performed. Postoperative course was satisfactory.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2004.10a
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• pp.416-421
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• 2004

Off-line feedrate scheduling is presented as the advanced technology to regulate cutting forces at the desired level through change of feedrates. In rough cutting, the feedrate scheduling aims at reducing the machining time, which is the most important factor for better productivity. Thus, the largest force which can avoid breakage of tool shank and tooth is a reference force for feedrate scheduling in rough cutting. In this paper, a calculation method of the reference cutting force for feedrate scheduling is developed. This model calculates rupture plane of tooth using the FEM analysis of a tool and computes the reference force using the transverse rupture strength of a tool. Experiments validate that the presented feedrate scheduling model reduced machining time drastically and regulate cutting forces at the reference cutting force.

• Nuclear Engineering and Technology
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• v.51 no.8
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• pp.1939-1950
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• 2019

The MELCOR code useful for a plant-specific hydrogen risk analysis has inevitable limitations in prediction of a turbulent flow of a hydrogen mixture. To investigate the accuracy of the hydrogen risk analysis by the MELCOR code, results for the turbulent gas behavior at pipe rupture accident were compared with CFX results which were verified by the American National Standard Institute (ANSI) model. The postulated accident scenario was selected to be surge line failure induced by station blackout of an Optimized Power Reactor 1000 MWe (OPR1000). When the surge line failure occurred, the flow out of the surgeline was strongly turbulent, from which the MELCOR code predicted that a substantial amount of hydrogen could be released. Nevertheless, the results indicated nonflammable mixtures owing to the high steam concentration released before the failure. On the other hand, the CFX code solving the three-dimensional fluid dynamics by incorporating the turbulence closure model predicted that the flammable area continuously existed at the jet interface even in the rising hydrogen mixtures. In conclusion, this study confirmed that the MELCOR code, which has limitations in turbulence analysis, could underestimate the existence of local combustible gas at pipe rupture accident. This clear comparison between two codes can contribute to establishing a guideline for computational hydrogen risk analysis.