• Journal of the Korea Concrete Institute
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• v.22 no.1
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• pp.113-122
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• 2010

Corrosion of prestressing tendons and wire fractures in grouted post-tensioned prestressed concrete bridges have been considered as a serious safety problem. In bridge evaluation the condition of prestressing tendons should be inspected, and if corroded tendons are found, the loss of tendon area should be included when we calculate the ultimate strength. In the previous study, it was evaluated that continuous acoustic monitoring techniques could be considered as a reliable non-destructive method for detecting wire fractures of fully grouted post-tensioned prestressing tendons. In the present study, an experimental test was performed for detecting wire fractures of post-tensioned prestressing tendons which are prestressed lower than current design level. A 10 m prestressed concrete beam was fabricated, which included two tendons prestressed 66 percentage and 40 percentage of tensile strength, respectively. The corrosion of two tendons was induced by an accelerated corrosion equipment and the test beam was monitored by using seven acoustic sensors and a continuous acoustic monitoring system. From each prestressing tendon, two acoustic signals of wire fractures were successfully detected and source locations were estimated within 20 mm error. Based on the test results, it is considered that continuous acoustic monitoring techniques can be applied to detect low-prestressed wire fracture in fully grouted post-tensioned prestressed concrete beams.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2005.10a
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• pp.427-430
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• 2005

Improving the productivity of steel cord is required due to the increase in demand for it, even though steel cord being used as a reinforcement of a tire has been produced at multi-pass wet wire drawing process over 1000m/min. To improve the productivity, if just increase drawing speed, it causes temperature rise, fracture arisen by embrittlement during drawing process. To increase drawing speed affecting productivity, the variation of wire temperature during multi-pass wet wire drawing process is investigated in this study. In result, the multi-pass wet wire drawing process is redesigned. The redesigned wet drawing process with 27 passes efficiently controls wire temperature during drawing process. It, therefore, enables drawing process to be possible at ultra high speed with 2000m/min. It becomes possible to improve the productivity of steel cord in this paper because the increase in drawing speed could be achieved.

• Journal of radiological science and technology
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• v.22 no.2
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• pp.23-26
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• 1999

The Zygomatic arch is structurally protruded and is easily fractured. The classic management of zygomatic arch fracture has been mentioned the Keen, Lothrop, Dingman and Ailing and threaded K-wire. All of the above methods have advantages and disadvantages. To minimize the disadvantages, we performed threaded K-wire for the first time using C-arm image intensifier. The subjects were 16 patients with Knight North group II (Zygomatic arch fracture). Among them the C-arm was used in 12 patients and the operator used sensitivity general method in 4 patients and confirmed the operation by mobile X-ray equipment. In conclusion, both groups were satisfied surgically and cosmetically. Using the C-arm, actual image at the time operation was clear and satisfied, the surrounding tissue damage was minimized and at was more accurately completed. The operation time was shortened by 30 to 60 minutes proving it to be an efficient method. We suggest though that further studies be needed to evaluate the radiation effect on these patients.

• Journal of Chest Surgery
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• v.28 no.2
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• pp.218-220
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• 1995

This 51 years old male patient was admitted to the department of thoracic and cardiovascular surgery via OPD because of anterior chest pain. 7days before admission, He got the chest trauma after traffic accidents,the lateral chest roentgenogram showed complete transverse sternal fracture. He also complained of mild dyspnea. We also noticed that he had depressed anterior chest wall. It looks like funnel chest. The operative findings revealed dislocated & callus formations at the both 4th and 5th costochondral junction and transverse fracture of sternal body between 4th and 5th costochondral junction, the upper end of sternal fracture was situated below the lower end of sternal fracture. The two ends of sternal fracture were situated at the same level and reapproximated the two ends by two-interrupted wire sutures. The patient is well on the road to recovery after the operation.

• Journal of Veterinary Clinics
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• v.20 no.1
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• pp.134-137
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• 2003

A 5-year-old, male mixed breed dog was presented to Gyeongsang National University Animal Hospital for bilateral mandibular open fracture by bite. The dog had loss of the teeth and injury of the oral mucosa. Radio-graphic and blood examinations were conducted. Fracture lines were observed between first premolar and second premolar, but temporomandibular luxation was not observed on radiographs. In serum analysis, elevated levels of CPK and LDH were found. The dog was anesthetized and prepared for aseptic surgery. Acrylic external skeletal fixator with Kirschiner wire was applied. Pin loosening and malalignment of the right fracture line was observed at 7 weeks after surgery. We applied Kirschner-Ehmer fixator and half pins during the second surgical procedure. At 4 weeks after a second surgical procedure, the fixator and pins were removed from mandible. The fractures were healed with no complications.

• Journal of Veterinary Clinics
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• v.37 no.6
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• pp.363-366
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• 2020

A 2-month-old, 50 kg male Korean native calf was referred with bilateral mandibular fractures. The bilateral mandible was hanging loose, with inability to use the jaw, indicated by excessive salivation. Radiography revealed a long oblique fracture in the right mandible, and a short oblique fracture in the left mandible. Computerized Tomography, a different form of radiography, revealed the fracture in the left mandible to be a comminuted fracture. In order to stabilize the bilateral mandible fractures, a combination of bone plate and wiring was applied; in addition, resin was applied to enhance stabilization of the mandible. Six weeks after surgery, the calf was able to masticate and ruminate well. In this case, application of the plate and wiring with resin to bilateral mandibular fractures presented a successful functional recovery. Accordingly, the combination of bone plate and wiring with resin can be an effective technique for treating mandibular fractures.

• Proceedings of the Korea Concrete Institute Conference
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• 1993.04a
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• pp.136-141
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• 1993

8 Wall specimens (1/2 scaled) used welded wire fabric (Ф=6mm) and ordinary deformed reinforcement(D6) of which their ultimate tensile strength were almost same were tested to investigate the inplane-flexural behavior. Test results show that : 1. The wall strength with welded wire fabric was 20% less than that with deformed bar. 2. The wall ductility ratio of welded wire fabric was 1/3 times than that of deformed bar, approximately. 3. It is recommened that lap splice of welded sire fabric should be avoided in critical fracture zone.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.5 no.1
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• pp.43-50
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• 1996

From a manufacturing standpoint it would be desirable to monitor the degradation of drawing die, that is essential for the maintenance of die quality, the evaluation of product integrity and the reducing scrap. Acoustic emission is powerful method in monitoring fine wire drawing process, especially in detecting the die fracture at early stage. Experiments also suggested that acoustic emission sigals contained valuable information regarding the stage of a drawing process such as the surface appearance of products and the condition of lubrication. These informations are AE monitoring techniques a possible tool in monitoring the drawing process operation. In order to approach this, this paper discusses the nature of acoustic emission signal presented which illustrate the effects of wire and die material, lubricants, and drawing speed on the generation and the mean voltage level of acoustic emission signal. From these experimental, results, we understanded controlling factors of acoustic emission generation.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.10a
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• pp.89-92
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• 2004

This paper is concerned with the drawing process of Al-Si wire. In this study, the finite-element model established in previous work was used to analyze the effects of various forming parameters, which included the reduction in area, the semi-die angle, the aspect ratio and the inter-particle spacing of the Si in drawing processes. The finite-element results gave the consolidation condition. From the results of analysis, the effects of each forming parameter were determined. It is possible to obtain the important basic data which can be guaranteed in the fracture prevention of Al-Si wire by using FEM simulation.

• Journal of Chest Surgery
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• v.44 no.3
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• pp.250-252
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• 2011

A sixty-year-old man was admitted due to chest pain. He had a history of pelvic bone fracture fixation with Kirschner wire about 20 years earlier. On examination, we detected a Kirschner wire that had migrated into the right ventricle. Without cardiopulmonary bypass, we removed the migrating Kirschner wire via median sternotomy. The patient recovered without complications and was discharged on the 5th postoperative day.